TY - JOUR TI - Ocular Complications of Diabetes and Therapeutic Approaches AU - Vieira-Potter, Victoria J. AU - Karamichos, Dimitrios AU - Lee, Darren J. T2 - BioMed Research International AB - Diabetes mellitus (DM) is a metabolic disease defined by elevated blood glucose (BG). DM is a global epidemic and the prevalence is anticipated to continue to increase. The ocular complications of DM negatively impact the quality of life and carry an extremely high economic burden. While systemic control of BG can slow the ocular complications they cannot stop them, especially if clinical symptoms are already present. With the advances in biodegradable polymers, implantable ocular devices can slowly release medication to stop, and in some cases reverse, diabetic complications in the eye. In this review we discuss the ocular complications associated with DM, the treatments available with a focus on localized treatments, and what promising treatments are on the horizon. DA - 2016/// PY - 2016 DO - 10.1155/2016/3801570 DP - PubMed Central VL - 2016 J2 - Biomed Res Int SN - 2314-6133 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4826913/ Y2 - 2018/03/07/16:33:54 L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4826913/ ER - TY - JOUR TI - Global prevalence and major risk factors of diabetic retinopathy AU - Yau, Joanne W. Y. AU - Rogers, Sophie L. AU - Kawasaki, Ryo AU - Lamoureux, Ecosse L. AU - Kowalski, Jonathan W. AU - Bek, Toke AU - Chen, Shih-Jen AU - Dekker, Jacqueline M. AU - Fletcher, Astrid AU - Grauslund, Jakob AU - Haffner, Steven AU - Hamman, Richard F. AU - Ikram, M. Kamran AU - Kayama, Takamasa AU - Klein, Barbara E. K. AU - Klein, Ronald AU - Krishnaiah, Sannapaneni AU - Mayurasakorn, Korapat AU - O'Hare, Joseph P. AU - Orchard, Trevor J. AU - Porta, Massimo AU - Rema, Mohan AU - Roy, Monique S. AU - Sharma, Tarun AU - Shaw, Jonathan AU - Taylor, Hugh AU - Tielsch, James M. AU - Varma, Rohit AU - Wang, Jie Jin AU - Wang, Ningli AU - West, Sheila AU - Xu, Liang AU - Yasuda, Miho AU - Zhang, Xinzhi AU - Mitchell, Paul AU - Wong, Tien Y. AU - Meta-Analysis for Eye Disease (META-EYE) Study Group T2 - Diabetes Care AB - OBJECTIVE: To examine the global prevalence and major risk factors for diabetic retinopathy (DR) and vision-threatening diabetic retinopathy (VTDR) among people with diabetes. RESEARCH DESIGN AND METHODS: A pooled analysis using individual participant data from population-based studies around the world was performed. A systematic literature review was conducted to identify all population-based studies in general populations or individuals with diabetes who had ascertained DR from retinal photographs. Studies provided data for DR end points, including any DR, proliferative DR, diabetic macular edema, and VTDR, and also major systemic risk factors. Pooled prevalence estimates were directly age-standardized to the 2010 World Diabetes Population aged 20-79 years. RESULTS: A total of 35 studies (1980-2008) provided data from 22,896 individuals with diabetes. The overall prevalence was 34.6% (95% CI 34.5-34.8) for any DR, 6.96% (6.87-7.04) for proliferative DR, 6.81% (6.74-6.89) for diabetic macular edema, and 10.2% (10.1-10.3) for VTDR. All DR prevalence end points increased with diabetes duration, hemoglobin A(1c), and blood pressure levels and were higher in people with type 1 compared with type 2 diabetes. CONCLUSIONS: There are approximately 93 million people with DR, 17 million with proliferative DR, 21 million with diabetic macular edema, and 28 million with VTDR worldwide. Longer diabetes duration and poorer glycemic and blood pressure control are strongly associated with DR. These data highlight the substantial worldwide public health burden of DR and the importance of modifiable risk factors in its occurrence. This study is limited by data pooled from studies at different time points, with different methodologies and population characteristics. DA - 2012/03// PY - 2012 DO - 10.2337/dc11-1909 DP - PubMed VL - 35 IS - 3 SP - 556 EP - 564 J2 - Diabetes Care LA - eng SN - 1935-5548 L2 - http://www.ncbi.nlm.nih.gov/pubmed/22301125 KW - Adult KW - Aged KW - Blood Glucose KW - Blood Pressure KW - Diabetic Retinopathy KW - Female KW - Humans KW - Male KW - Middle Aged KW - Prevalence KW - Risk Factors KW - Young Adult ER - TY - ELEC TI - WHO | Diabetes country profiles 2016 T2 - WHO AB - In order to combat the global epidemic of diabetes and noncommunicable diseases (NCDs), it is imperative to create a baseline for monitoring trends and to assess the progress of countries in addressing the epidemic. UR - http://www.who.int/diabetes/country-profiles/en/ Y2 - 2018/03/07/15:45:37 L2 - http://www.who.int/diabetes/country-profiles/en/ ER - TY - CHAP TI - Diabetes Mellitus: Diagnosis, Classification, and Pathophysiology AU - Powers, Alvin C. T2 - Harrison's Principles of Internal Medicine A2 - Kasper, Dennis A2 - Fauci, Anthony A2 - Hauser, Stephen A2 - Longo, Dan A2 - Jameson, J. Larry A2 - Loscalzo, Joseph AB - Diabetes mellitus (DM) refers to a group of common metabolic disorders that share the phenotype of hyperglycemia. Several distinct types of DM are caused by a complex interaction of genetics and environmental factors. Depending on the etiology of the DM, factors contributing to hyperglycemia include reduced insulin secretion, decreased glucose utilization, and increased glucose production. The metabolic dysregulation associated with DM causes secondary pathophysiologic changes in multiple organ systems that impose a tremendous burden on the individual with diabetes and on the health care system. In the United States, DM is the leading cause of end-stage renal disease (ESRD), nontraumatic lower extremity amputations, and adult blindness. It also predisposes to cardiovascular diseases. With an increasing incidence worldwide, DM will be likely a leading cause of morbidity and mortality in the future. CY - New York, NY DA - 2015/// PY - 2015 DP - Access Medicine ET - 19 PB - McGraw-Hill Education ST - Diabetes Mellitus UR - accessmedicine.mhmedical.com/content.aspx?aid=1120816080 Y2 - 2018/03/07/15:41:21 L2 - http://accessmedicine.mhmedical.com.ez.urosario.edu.co/content.aspx?bookid=1130§ionid=79752868#1120815998 ER - TY - BOOK TI - IDF Diabetes Atlas AU - International Diabetes Federation CY - Brussels, Belgium DA - 2019/// PY - 2019 ET - 9 PB - International Diabetes Federation UR - https://www.diabetesatlas.org/upload/resources/material/20200302_133351_IDFATLAS9e-final-web.pdf Y2 - 2020/11/03/14:20:44 ER - TY - JOUR TI - In vitro scratch assay: a convenient and inexpensive method for analysis of cell migration in vitro AU - Liang, Chun-Chi AU - Park, Ann Y. AU - Guan, Jun-Lin T2 - Nature Protocols AB - The in vitro scratch assay is an easy, low-cost and well-developed method to measure cell migration in vitro. The basic steps involve creating a "scratch" in a cell monolayer, capturing the images at the beginning and at regular intervals during cell migration to close the scratch, and comparing the images to quantify the migration rate of the cells. Compared to other methods, the in vitro scratch assay is particularly suitable for studies on the effects of cell-matrix and cell-cell interactions on cell migration, mimic cell migration during wound healing in vivo and are compatible with imaging of live cells during migration to monitor intracellular events if desired. Besides monitoring migration of homogenous cell populations, this method has also been adopted to measure migration of individual cells in the leading edge of the scratch. Not taking into account the time for transfection of cells, in vitro scratch assay per se usually takes from several hours to overnight. DA - 2007/// PY - 2007 DO - 10.1038/nprot.2007.30 DP - PubMed VL - 2 IS - 2 SP - 329 EP - 333 J2 - Nat Protoc LA - eng SN - 1750-2799 ST - In vitro scratch assay L2 - http://www.ncbi.nlm.nih.gov/pubmed/17406593 KW - Cell Movement KW - Cytological Techniques KW - Image Interpretation, Computer-Assisted KW - In Vitro Techniques KW - Microscopy, Fluorescence KW - Microscopy, Phase-Contrast KW - Staining and Labeling ER - TY - JOUR TI - Ca2+ mobilization in bovine corneal endothelial cells by P2 purinergic receptors AU - Srinivas, S. P. AU - Yeh, J. C. AU - Ong, A. AU - Bonanno, J. A. T2 - Current Eye Research AB - PURPOSE: To characterize Ca2+ mobilization by P2 receptors in the bovine corneal endothelial cells (BCEC). METHODS: Changes in intracellular Ca2+ ([Ca2+]i) were measured by fluorescence imaging of cultured and fresh BCEC cells loaded with the Ca2+-sensitive dye Fura-PE3. Relative rates of Ca2+ influx were measured employing Mn2+ as a surrogate for Ca2+. RESULTS: Exposure of cultured cells to uridine 5'-triphosphate (UTP), 2-methyl-thio ATP (msATP) and ATP caused biphasic changes in [Ca2+]i consisting of a peak followed by a plateau phase. Based on the peak responses to 100 microM agonist, the magnitude of UTP responses were similar to that of ATP but greater than that of msATP or ADP. UTP and msATP stimulated Mn2+ influx following [Ca2+]i peak similar to that observed in response to cyclopiazonic acid (CPA), an inhibitor of ER Ca2+-ATPase. Under Ca2+-free conditions, peak responses were similar to those in the presence of external Ca2+, but reduced when the cells were pre-exposed to CPA. Reactive Blue-2 (RB2), inhibited msATP responses by 60.4 +/- 18.8% but UTP responses by only 10.6 +/- 9.5%. Repeated exposures to UTP or msATP reduced [Ca2+]i mobilization indicating homologous desensitization. Response to UTP was not affected by a prior exposure to msATP. However, response to msATP was reduced by a prior exposure to UTP indicating mixed heterologous desensitization. Fresh cells responded to UTP (50 microM) with temporal characteristics of [Ca2+]i mobilization similar to that of cultured cells. CONCLUSION: BCEC express P2 receptors belonging to the P2Y subfamily. The emptying of the IP3-sensitive stores, leading to the initial peak in [Ca2+]i response, subsequently caused capacitative Ca2+ influx leading to the onset of the plateau phase. A significant homologous desensitization to UTP and msATP, selective heterologous desensitization between UTP and msATP, and selective inhibition by RB2 indicate the coexistence of multiple P2Y receptors. DA - 1998/10// PY - 1998 DP - PubMed VL - 17 IS - 10 SP - 994 EP - 1004 J2 - Curr. Eye Res. LA - eng SN - 0271-3683 L2 - http://www.ncbi.nlm.nih.gov/pubmed/9788302 KW - Adenosine Triphosphate KW - Animals KW - Calcium KW - Calcium-Transporting ATPases KW - Cattle KW - Cells, Cultured KW - Dose-Response Relationship, Drug KW - Endothelium, Corneal KW - Enzyme Inhibitors KW - Fluorescent Dyes KW - Fura-2 KW - Indoles KW - Manganese KW - Receptors, Purinergic P2 KW - Thionucleotides KW - Uridine Triphosphate ER - TY - JOUR TI - The effects of dexamethasone on the Na,K-ATPase activity and pump function of corneal endothelial cells AU - Hatou, Shin AU - Yamada, Masakazu AU - Mochizuki, Hiroshi AU - Shiraishi, Atsushi AU - Joko, Takeshi AU - Nishida, Teruo T2 - Current Eye Research AB - PURPOSE: The Na(+)- and K(+)-dependent ATPase (Na,K-ATPase) expressed in the basolateral membrane of corneal endothelial cells plays an important role in the pump function of the corneal endothelium. We investigated the possible role of dexamethasone in the regulation of Na,K-ATPase activity and pump function in corneal endothelial cells. METHODS: Confluent monolayers of mouse corneal endothelial cells were exposed to dexamethasone. ATPase activity of the cells was evaluated by spectrophotometric measurement of phosphate released from ATP with the use of ammonium molybdate, with Na,K-ATPase activity being defined as the portion of total ATPase activity sensitive to ouabain. Pump function of the cells was measured with the use of an Ussing chamber, with the pump function attributable to Na,K-ATPase activity being defined as the portion of the total short-circuit current sensitive to ouabain. Western blot analysis was examined to measure the expression of the Na,K-ATPase alpha(1)-subunit. RESULTS: Dexamethasone (1 or 10 microM) increased the Na,K-ATPase activity and pump function of the cultured cells. These effects of dexamethasone were blocked by cycloheximide, a protein synthesis inhibitor. Western blot analysis also indicated that dexamethasone increased the expression of the Na,K-ATPase alpha(1)-subunit, whereas it decreased the expression of the phospho-Na,K-ATPase alpha(1)-subunit. CONCLUSIONS: Our results suggest that dexamethasone stimulates Na,K-ATPase activity in mouse corneal endothelial cells. The effect of dexamethasone activation in these cells is mediated by Na,K-ATPase synthesis and increase in an enzymatic activity by dephosphorylation of Na,K-ATPase alpha(1)-subunits. DA - 2009/05// PY - 2009 DO - 10.1080/02713680902829624 DP - PubMed VL - 34 IS - 5 SP - 347 EP - 354 J2 - Curr. Eye Res. LA - eng SN - 1460-2202 L2 - http://www.ncbi.nlm.nih.gov/pubmed/19401877 KW - Animals KW - Cell Line, Transformed KW - Cycloheximide KW - Dexamethasone KW - Down-Regulation KW - Electric Conductivity KW - Endothelium, Corneal KW - Enzyme Inhibitors KW - Glucocorticoids KW - Mice KW - Ouabain KW - Phosphorylation KW - Protein Synthesis Inhibitors KW - Sodium-Potassium-Exchanging ATPase KW - Up-Regulation ER - TY - JOUR TI - Cell Signaling in Regulation of the Barrier Integrity of the Corneal Endothelium AU - Srinivas, Sangly P. T2 - Experimental Eye Research AB - The barrier integrity of the corneal endothelium, which is conferred by its tight and adherens junctions, is critical for the maintenance of deturgescence of the corneal stroma. Although characteristically leaky, the barrier integrity restricts fluid leakage into the stroma such that the rate of leak does not exceed the rate of the endothelial active fluid transport directed toward the aqueous humor. At a molecular level, the barrier integrity is influenced by the actin cytoskeleton and microtubules, which are coupled to tight and adherens junctions via a variety of linker proteins. Since the cytoskeleton is affected by Rho family small GTPases and p38 MAP kinase, among others, many pathophysiological stimuli induce plasticity to the cytoskeleton and thereby elicit dynamic regulation of the barrier integrity. This review presents an overview of the impact of several bioactive factors on the barrier integrity of the corneal endothelium through altered actin cytoskeleton and/or disassembly of microtubules. The main focus is on the effect of TNF-α (tumor necrosis factor-α) which is a pro-inflammatory molecule found in the intraocular milieu during allograft rejection and anterior uveitis. This cytokine elicits acute activation of p38 MAP kinase, induces disassembly of microtubules, disrupts the peri-junctional actomyosin ring, and concomitantly breaks down the barrier integrity. These effects of TNF-α could be inhibited by stabilizing the microtubules, co-treating with a selective p38 MAP kinase inhibitor, and elevating intracellular cAMP via A2B receptors or direct exposure to forskolin. Overall, the corneal edema following a potential breakdown of the endothelial barrier integrity can be rescued pharmacologically by inhibiting specific cell-signaling mechanisms. DA - 2012/02// PY - 2012 DO - 10.1016/j.exer.2011.09.009 DP - PubMed Central VL - 95 IS - 1 SP - 8 EP - 15 J2 - Exp Eye Res SN - 0014-4835 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3271188/ Y2 - 2018/03/13/17:08:09 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3271188/pdf/nihms328195.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3271188/ ER - TY - JOUR TI - The human corneal endothelium: new insights into electrophysiology and ion channels AU - Mergler, Stefan AU - Pleyer, Uwe T2 - Progress in Retinal and Eye Research AB - The corneal endothelium is a monolayer that mediates the flux of solutes and water across the posterior corneal surface. Thereby, it plays an essential role to maintain the transparency of the cornea. Unlike the epithelium, the human endothelium is an amitotic cell layer with a critical cell density and the risk of corneal decompensation. The number of endothelial cells subsequently decreases with age. Moreover, the endothelial cell loss is accelerated after various impairments such as surgical trauma (e.g. cataract extraction) and following corneal transplantation. This cell loss is associated with programmed cell death (apoptosis) and changed ion channel activity. However, little is known about the electrophysiology and ion channel expression (in particular Ca2+ channels) in corneal endothelial cells. This article reviews our current knowledge about the electrophysiology of the corneal endothelium. It highlights ion channel expression, which may have a major role in corneal cell physiology and pathological events. A better understanding of the (electro)physiological function of the cornea may lead to the development of clinical relevant new therapeutic and preventive measures. DA - 2007/07// PY - 2007 DO - 10.1016/j.preteyeres.2007.02.001 DP - PubMed VL - 26 IS - 4 SP - 359 EP - 378 J2 - Prog Retin Eye Res LA - eng SN - 1350-9462 ST - The human corneal endothelium L2 - http://www.ncbi.nlm.nih.gov/pubmed/17446115 KW - Apoptosis KW - Cell Membrane Permeability KW - Endothelium, Corneal KW - Humans KW - Ion Channels KW - Ion Transport KW - Membrane Potentials ER - TY - JOUR TI - Corneal endothelium and central corneal thickness changes in type 2 diabetes mellitus AU - El-Agamy, Amira AU - Alsubaie, Shams T2 - Clinical Ophthalmology (Auckland, N.Z.) AB - PURPOSE: This study was conducted to compare the corneal endothelial cell density (ECD), morphological features, and central corneal thickness (CCT) in type 2 diabetes mellitus (DM) with age-matched, nondiabetic control subjects using EM-3000 Specular Microscope. STUDY DESIGN: This was a prospective, hospital-based, nonrandomized, case-control, observational, and quantitative study. SUBJECTS AND METHODS: The study included 57 patients (57 eyes) with type 2 DM and 45 control (nondiabetic) subjects (45 eyes). The corneal endothelial structure and CCT were examined in all eyes by noncontact specular microscopy using EM-3000 Specular Microscope. The endothelial structure was studied for ECD, coefficient of variation of cell area (CV), and percentage of hexagonal cells. RESULTS: The study included 36 eyes without diabetic retinopathy (DR), 14 eyes with nonproliferative DR, and 7 eyes with proliferative DR. There were 26 eyes with a duration of ≤10 years and 31 eyes with a duration of >10 years. Also, there were 24 eyes with HbA1c≤7.5% and 33 eyes with HbA1c>7.5%. ECD was significantly lower in the diabetic cornea than in control group (P=0.014). CV was higher in diabetic cornea (P=0.008). The diabetic cornea group had lower percentage of hexagonal cells than the control group, but the difference was not statistically significant (P=0.603). Also, diabetic cornea was thicker than control group, but not statistically significant (P=0.301). CONCLUSION: This study documented that type 2 DM causes a significant reduction of ECD and increased CV (polymegathism). Also, diabetic cornea has increased CCT and lower percentage of hexagonal cells than normal subjects, but without statistical significance. DA - 2017/// PY - 2017 DO - 10.2147/OPTH.S126217 DP - PubMed VL - 11 SP - 481 EP - 486 J2 - Clin Ophthalmol LA - eng SN - 1177-5467 L1 - https://www.dovepress.com/getfile.php?fileID=35249 L2 - http://www.ncbi.nlm.nih.gov/pubmed/28280298 L2 - http://www.ncbi.nlm.nih.gov/pubmed/28280298 KW - central corneal thickness KW - diabetes mellitus KW - diabetic retinopathy KW - endothelial cell density KW - noncontact specular microscopy ER - TY - JOUR TI - Changes in the corneal endothelial cell density and morphology in patients with type 2 diabetes mellitus: a population-based study, Sankara Nethralaya Diabetic Retinopathy and Molecular Genetics Study (SN-DREAMS, Report 23) AU - Sudhir, Rachapalle R. AU - Raman, Rajiv AU - Sharma, Tarun T2 - Cornea AB - PURPOSE: To study the corneal endothelial cell density and morphological features in type 2 diabetic patients (cases) and compare it with nondiabetic subjects (controls) in a population-based cross-sectional study. METHODS: Patients were recruited from the Sankara Nethralaya--Diabetic Retinopathy Epidemiology and Molecular Genetic Study, a population-based study to estimate the prevalence of type 2 diabetes and diabetic retinopathy in urban Chennai, South India. Corneal endothelial morphological features were recorded in all subjects using noncontact specular microscopy and central corneal thickness was measured using ultrasound pachymeter. RESULTS: A total of 1191 cases and 121 controls were enrolled into the study. The mean corneal endothelial cell density (cells/mm(2)) was lower in cases than in controls (2550 ± 326 vs. 2634 ± 256; P = 0.001). No difference was observed in the mean pachymetry values, hexagonality %, and coefficient of variation of cell size between cases and controls. Multivariate regression analysis, after adjusting for age, showed the mean cell density to be lesser by 66 cells/mm(2) (95% confidence interval, 6.3-125.9) among diabetic patients compared with nondiabetic subjects. CONCLUSIONS: The results of this study, from a large population-based sample, support the earlier theories of lower endothelial cell counts among subjects with type 2 diabetes mellitus in comparison with nondiabetic controls. DA - 2012/10// PY - 2012 DO - 10.1097/ICO.0b013e31823f8e00 DP - PubMed VL - 31 IS - 10 SP - 1119 EP - 1122 J2 - Cornea LA - eng SN - 1536-4798 ST - Changes in the corneal endothelial cell density and morphology in patients with type 2 diabetes mellitus L2 - http://www.ncbi.nlm.nih.gov/pubmed/22357387 KW - Adult KW - Aged KW - Cell Count KW - Cell Shape KW - Cell Size KW - Corneal Endothelial Cell Loss KW - Corneal Pachymetry KW - Cross-Sectional Studies KW - Diabetes Complications KW - Diabetes Mellitus, Type 2 KW - Diabetic Retinopathy KW - Endothelium, Corneal KW - Female KW - Humans KW - India KW - Male KW - Microscopy KW - Middle Aged ER - TY - JOUR TI - Diabetic complications in the cornea AU - Ljubimov, Alexander V. T2 - Vision Research T3 - Diabetic Retinopathy - an Overview AB - Diabetic corneal alterations, such as delayed epithelial wound healing, edema, recurrent erosions, neuropathy/loss of sensitivity, and tear film changes are frequent but underdiagnosed complications of both type 1 (insulin-dependent) and type 2 (non-insulin-dependent) diabetes mellitus. The disease affects corneal epithelium, corneal nerves, tear film, and to a lesser extent, endothelium, and also conjunctiva. These abnormalities may appear or become exacerbated following trauma, as well as various surgeries including retinal, cataract or refractive. The focus of the review is on mechanisms of diabetic corneal abnormalities, available animal, tissue and organ culture models, and emerging treatments. Changes of basement membrane structure and wound healing rates, the role of various proteinases, advanced glycation end products (AGEs), abnormal growth and motility factors (including opioid, epidermal, and hepatocyte growth factors) are analyzed. Experimental therapeutics under development, including topical naltrexone, insulin, inhibitors of aldose reductase, and AGEs, as well as emerging gene and cell therapies are discussed in detail. DA - 2017/10/01/ PY - 2017 DO - 10.1016/j.visres.2017.03.002 DP - ScienceDirect VL - 139 SP - 138 EP - 152 J2 - Vision Research SN - 0042-6989 UR - http://www.sciencedirect.com/science/article/pii/S0042698917300470 Y2 - 2018/03/13/16:51:28 L1 - https://ac.els-cdn.com/S0042698917300470/1-s2.0-S0042698917300470-main.pdf?_tid=a7e674e1-39b3-4540-9462-e0344131ae70&acdnat=1520960068_3ac4bd7570f761f4ad360c66c4e9b439 L2 - https://www.sciencedirect.com/science/article/pii/S0042698917300470 KW - AGEs KW - Corneal epithelium KW - Diabetic cornea KW - Dry eye KW - Gene therapy KW - Growth factors KW - Insulin KW - Keratopathy KW - Limbal stem cell KW - Naltrexone KW - Neuropathy KW - Proteinases ER - TY - JOUR TI - Mutations in LOXHD1, a recessive-deafness locus, cause dominant late-onset Fuchs corneal dystrophy AU - Riazuddin, S. Amer AU - Parker, David S. AU - McGlumphy, Elyse J. AU - Oh, Edwin C. AU - Iliff, Benjamin W. AU - Schmedt, Thore AU - Jurkunas, Ula AU - Schleif, Robert AU - Katsanis, Nicholas AU - Gottsch, John D. T2 - American Journal of Human Genetics AB - Fuchs corneal dystrophy (FCD) is a genetic disorder of the corneal endothelium and is the most common cause of corneal transplantation in the United States. Previously, we mapped a late-onset FCD locus, FCD2, on chromosome 18q. Here, we present next-generation sequencing of all coding exons in the FCD2 critical interval in a multigenerational pedigree in which FCD segregates as an autosomal-dominant trait. We identified a missense change in LOXHD1, a gene causing progressive hearing loss in humans, as the sole variant capable of explaining the phenotype in this pedigree. We observed LOXHD1 mRNA in cultured human corneal endothelial cells, whereas antibody staining of both human and mouse corneas showed staining in the corneal epithelium and endothelium. Corneal sections of the original proband were stained for LOXHD1 and demonstrated a distinct increase in antibody punctate staining in the endothelium and Descemet membrane; punctate staining was absent from both normal corneas and FCD corneas negative for causal LOXHD1 mutations. Subsequent interrogation of a cohort of >200 sporadic affected individuals identified another 15 heterozygous missense mutations that were absent from >800 control chromosomes. Furthermore, in silico analyses predicted that these mutations reside on the surface of the protein and are likely to affect the protein's interface and protein-protein interactions. Finally, expression of the familial LOXHD1 mutant allele as well as two sporadic mutations in cells revealed prominent cytoplasmic aggregates reminiscent of the corneal phenotype. All together, our data implicate rare alleles in LOXHD1 in the pathogenesis of FCD and highlight how different mutations in the same locus can potentially produce diverse phenotypes. DA - 2012/03/09/ PY - 2012 DO - 10.1016/j.ajhg.2012.01.013 DP - PubMed VL - 90 IS - 3 SP - 533 EP - 539 J2 - Am. J. Hum. Genet. LA - eng SN - 1537-6605 L1 - https://www.cell.com/article/S000292971200047X/pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/22341973 L2 - http://www.ncbi.nlm.nih.gov/pubmed/22341973 KW - Alleles KW - Animals KW - Carrier Proteins KW - Case-Control Studies KW - Cells, Cultured KW - Chromosomes KW - Cohort Studies KW - Endothelium, Corneal KW - Exome KW - Exons KW - Fuchs' Endothelial Dystrophy KW - Genetic Linkage KW - Genetic Loci KW - Genetic Variation KW - Genome-Wide Association Study KW - Haplotypes KW - Heterozygote KW - Humans KW - Introns KW - Mice KW - Mutation, Missense KW - Pedigree KW - Phenotype KW - RNA, Messenger ER - TY - JOUR TI - Functional assessment of SLC4A11, an integral membrane protein mutated in corneal dystrophies AU - Loganathan, Sampath K. AU - Schneider, Hans-Peter AU - Morgan, Patricio E. AU - Deitmer, Joachim W. AU - Casey, Joseph R. T2 - American Journal of Physiology-Cell Physiology AB - SLC4A11, a member of the SLC4 family of bicarbonate transporters, is a widely expressed integral membrane protein, abundant in kidney and cornea. Mutations of SLC4A11 cause some cases of the blinding corneal dystrophies, congenital hereditary endothelial dystrophy, and Fuchs endothelial corneal dystrophy. These diseases are marked by fluid accumulation in the corneal stroma, secondary to defective fluid reabsorption by the corneal endothelium. The role of SLC4A11 in these corneal dystrophies is not firmly established, as SLC4A11 function remains unclear. To clarify the normal function(s) of SLC4A11, we characterized the protein following expression in the simple, low-background expression system Xenopus laevis oocytes. Since plant and fungal SLC4A11 orthologs transport borate, we measured cell swelling associated with accumulation of solute borate. The plant water/borate transporter NIP5;1 manifested borate transport, whereas human SLC4A11 did not. SLC4A11 supported osmotically driven water accumulation that was electroneutral and Na+ independent. Studies in oocytes and HEK293 cells could not detect Na+-coupled HCO3− transport or Cl−/HCO3− exchange by SLC4A11. SLC4A11 mediated electroneutral NH3 transport in oocytes. Voltage-dependent OH− or H+ movement was not measurable in SLC4A11-expressing oocytes, but SLC4A11-expressing HEK293 cells manifested low-level cytosolic acidification at baseline. In mammalian cells, but not oocytes, OH−/H+ conductance may arise when SLC4A11 activates another protein or itself is activated by another protein. These data argue against a role of human SLC4A11 in bicarbonate or borate transport. This work provides additional support for water and ammonia transport by SLC4A11. When expressed in oocytes, SLC4A11 transported NH3, not NH3/H+. DA - 2016/08/24/ PY - 2016 DO - 10.1152/ajpcell.00078.2016 DP - physiology.org (Atypon) VL - 311 IS - 5 SP - C735 EP - C748 J2 - American Journal of Physiology-Cell Physiology SN - 0363-6143 UR - https://www.physiology.org/doi/abs/10.1152/ajpcell.00078.2016 Y2 - 2018/03/13/16:43:25 L1 - https://www.physiology.org/doi/pdf/10.1152/ajpcell.00078.2016?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed L2 - https://www.physiology.org/doi/abs/10.1152/ajpcell.00078.2016?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed ER - TY - JOUR TI - Targeted disruption of Col8a1 and Col8a2 genes in mice leads to anterior segment abnormalities in the eye AU - Hopfer, Ulrike AU - Fukai, Naomi AU - Hopfer, Helmut AU - Wolf, Gunter AU - Joyce, Nancy AU - Li, En AU - Olsen, Bjorn R. T2 - FASEB journal: official publication of the Federation of American Societies for Experimental Biology AB - Collagen VIII is localized in subendothelial and subepithelial extracellular matrices. It is a major component of Descemet's membrane, a thick basement membrane under the corneal endothelium, where it forms a hexagonal lattice structure; a similar structure, albeit less extensive, may be formed in other basement membranes. We have examined the function of collagen VIII in mice by targeted inactivation of the genes encoding the two polypeptide subunits, Col8a1 and Col8a2. Analysis of these mice reveals no major structural defects in most organs, but demonstrates that type VIII collagen is required for normal anterior eye development, particularly the formation of a corneal stroma with the appropriate number of fibroblastic cell layers and Descemet's membrane of appropriate thickness. Complete lack of type VIII collagen leads to dysgenesis of the anterior segment of the eye: a globoid, keratoglobus-like protrusion of the anterior chamber with a thin corneal stroma. Descemet's membrane is markedly thinned. The corneal endothelial cells are enlarged and reduced in number, and show a decreased ability to proliferate in response to different growth factors in vitro. An important function of collagen VIII may therefore be to generate a peri- or subcellular matrix environment that permits or stimulates cell proliferation. DA - 2005/08// PY - 2005 DO - 10.1096/fj.04-3019com DP - PubMed VL - 19 IS - 10 SP - 1232 EP - 1244 J2 - FASEB J. LA - eng SN - 1530-6860 L2 - http://www.ncbi.nlm.nih.gov/pubmed/16051690 KW - Animals KW - Anterior Eye Segment KW - Aorta KW - Cell Proliferation KW - Collagen Type VIII KW - Cornea KW - Endothelium, Corneal KW - Eye Abnormalities KW - Female KW - Gene Expression Regulation, Developmental KW - Male KW - Mice KW - Mice, Inbred C57BL ER - TY - JOUR TI - Evidence of oxidative stress in the pathogenesis of fuchs endothelial corneal dystrophy AU - Jurkunas, Ula V. AU - Bitar, Maya S. AU - Funaki, Toshinari AU - Azizi, Behrooz T2 - The American Journal of Pathology AB - Fuchs endothelial corneal dystrophy (FECD) is a progressive, blinding disease characterized by corneal endothelial (CE) cell apoptosis. Corneal transplantation is the only measure currently available to restore vision in these patients. Despite the identification of some genetic factors, the pathophysiology of FECD remains unclear. In this study, we observed a decrease in the antioxidant response element-driven antioxidants in FECD corneal endothelium. We further demonstrated that nuclear factor erythroid 2-related factor 2, a transcription factor known to bind the antioxidant response element and activate antioxidant defense, is down-regulated in FECD endothelium. Importantly, we detected significantly higher levels of oxidative DNA damage and apoptosis in FECD endothelium compared with normal controls and pseudophakic bullous keratopathy (iatrogenic CE cell loss) specimens. A marker of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine, colocalized to mitochondria, indicating that the mitochondrial genome is the specific target of oxidative stress in FECD. Oxidative DNA damage was not detected in pseudophakic bullous keratopathy corneas, whereas it colocalized with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells in FECD samples. Ex vivo, oxidative stress caused characteristic morphological changes and apoptosis of CE, suggestive of findings that characterize FECD in vivo. Together, these data suggest that suboptimal nuclear factor erythroid 2-related factor 2-regulated defenses may account for oxidant-antioxidant imbalance in FECD, which in turn leads to oxidative DNA damage and apoptosis. This study provides evidence that oxidative stress plays a key role in FECD pathogenesis. DA - 2010/11// PY - 2010 DO - 10.2353/ajpath.2010.100279 DP - PubMed VL - 177 IS - 5 SP - 2278 EP - 2289 J2 - Am. J. Pathol. LA - eng SN - 1525-2191 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20847286 KW - Animals KW - Antioxidants KW - Apoptosis KW - Cells, Cultured KW - Corneal Transplantation KW - DNA Damage KW - Endothelium, Corneal KW - Fuchs' Endothelial Dystrophy KW - Humans KW - Hydrogen Peroxide KW - Male KW - Membrane Potential, Mitochondrial KW - Mice KW - Mice, Inbred BALB C KW - Mice, Inbred C57BL KW - Microarray Analysis KW - Oxidants KW - Oxidative Stress ER - TY - JOUR TI - Decreased expression of peroxiredoxins in Fuchs' endothelial dystrophy AU - Jurkunas, Ula V. AU - Rawe, Ian AU - Bitar, Maya S. AU - Zhu, Cheng AU - Harris, Deshea L. AU - Colby, Kathryn AU - Joyce, Nancy C. T2 - Investigative Ophthalmology & Visual Science AB - PURPOSE: To compare the relative expression of peroxiredoxin (Prx) proteins in normal human corneal endothelium with endothelium in corneas affected by Fuchs' endothelial dystrophy (FED) and between normal human endothelium and epithelial/stromal tissue. METHODS: Human corneal endothelial cell-Descemet's membrane (HCEC-DM) complexes from normal and FED corneal buttons were dissected from the epithelium/stroma. For proteomic analysis, HCEC-DM protein extracts were separated by using two-dimensional gel electrophoresis. Relative differences in protein spot density was analyzed. Proteins of interest, including Prx isoforms, were identified by MALDI-TOF (matrix-assisted desorption ionization-time of flight) mass spectrometry. Western blot analysis compared the relative expression of Prx isoforms in normal and FED endothelium and between normal endothelium and normal epithelium/stroma. Expression of Prx-2 mRNA was compared by using real-time PCR. RESULTS: Proteomic analysis identified differences in the relative expression of Prx isoforms between normal and FED endothelium. Western blot analysis confirmed that expression of Prx-2, -3, and -5 was significantly decreased (P < 0.05) in FED cells. Normal HCECs expressed significantly (P < 0.05) higher levels of Prx-2 and -3 than did the epithelium/stroma. Expression of Prx-5 was not significantly different (P > 0.05) in the endothelium versus the epithelium/stroma. Real-time PCR analysis revealed that Prx-2 mRNA was significantly decreased (P = 0.027) in FED samples. CONCLUSIONS: Prx proteins were identified in human corneal endothelium. The fact that Prx-2 and -3 were expressed at significantly higher levels in HCEC-DM compared with the epithelium/stroma reflects the different physiologic activities of individual corneal cell types. Significantly decreased expression of Prx-2, -3, and -5 in FED may suggest an alteration in the ability of endothelial cells to withstand oxidant-induced damage and may be closely related to the pathogenesis of this disease. DA - 2008/07// PY - 2008 DO - 10.1167/iovs.07-1529 DP - PubMed VL - 49 IS - 7 SP - 2956 EP - 2963 J2 - Invest. Ophthalmol. Vis. Sci. LA - eng SN - 1552-5783 L2 - http://www.ncbi.nlm.nih.gov/pubmed/18378575 KW - Aged KW - Aged, 80 and over KW - Blotting, Western KW - Corneal Stroma KW - Down-Regulation KW - Endothelium, Corneal KW - Epithelium, Corneal KW - Female KW - Fuchs' Endothelial Dystrophy KW - Humans KW - Male KW - Middle Aged KW - Peroxiredoxin III KW - Peroxiredoxins KW - Protein Isoforms KW - Proteomics KW - Reference Values ER - TY - JOUR TI - E2-2 protein and Fuchs's corneal dystrophy AU - Baratz, Keith H. AU - Tosakulwong, Nirubol AU - Ryu, Euijung AU - Brown, William L. AU - Branham, Kari AU - Chen, Wei AU - Tran, Khoa D. AU - Schmid-Kubista, Katharina E. AU - Heckenlively, John R. AU - Swaroop, Anand AU - Abecasis, Goncalo AU - Bailey, Kent R. AU - Edwards, Albert O. T2 - The New England Journal of Medicine AB - BACKGROUND: Fuchs's corneal dystrophy (FCD) is a leading cause of corneal transplantation and affects 5% of persons in the United States who are over the age of 40 years. Clinically visible deposits called guttae develop under the corneal endothelium in patients with FCD. A loss of endothelial cells and deposition of an abnormal extracellular matrix are observed microscopically. In advanced disease, the cornea swells and becomes cloudy because the remaining endothelial cells are not sufficient to keep the cornea dehydrated and clear. Although rare genetic variation that contributes to both early-onset and typical late-onset forms of FCD has been identified, to our knowledge, no common variants have been reported. METHODS: We performed a genomewide association study and replicated the most significant observations in a second, independent group of subjects. RESULTS: Alleles in the transcription factor 4 gene (TCF4), encoding a member of the E-protein family (E2-2), were associated with typical FCD (P=2.3x10(-26)). The association increased the odds of having FCD by a factor of 30 for persons with two copies of the disease variants (homozygotes) and discriminated between case subjects and control subjects with about 76% accuracy. At least two regions of the TCF4 locus were associated independently with FCD. Alleles in the gene encoding protein tyrosine phosphatase receptor type G (PTPRG) were associated with FCD (P=4.0x10(-7)), but the association did not reach genomewide significance. CONCLUSIONS: Genetic variation in TCF4 contributes to the development of FCD. (Funded by the National Eye Institute and others.) DA - 2010/09/09/ PY - 2010 DO - 10.1056/NEJMoa1007064 DP - PubMed VL - 363 IS - 11 SP - 1016 EP - 1024 J2 - N. Engl. J. Med. LA - eng SN - 1533-4406 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20825314 KW - Alleles KW - Chromosomes, Human, Pair 13 KW - Cornea KW - Fuchs' Endothelial Dystrophy KW - Genome-Wide Association Study KW - Genotype KW - Humans KW - Polymorphism, Single Nucleotide KW - TCF Transcription Factors KW - Transcription Factor 7-Like 2 Protein ER - TY - JOUR TI - Screening and Characterization of Drugs That Protect Corneal Endothelial Cells Against Unfolded Protein Response and Oxidative Stress AU - Kim, Eun Chul AU - Toyono, Tetsuya AU - Berlinicke, Cynthia A. AU - Zack, Donald J. AU - Jurkunas, Ula AU - Usui, Tomohiko AU - Jun, Albert S. T2 - Investigative Ophthalmology & Visual Science AB - Purpose To screen for and characterize compounds that protect corneal endothelial cells against unfolded protein response (UPR) and oxidative stress. Methods Bovine corneal endothelial cells (BCECs) were treated for 48 hours with 640 compounds from a Food and Drug Administration (FDA)-approved drug library and then challenged with thapsigargin or H2O2 to induce UPR or oxidative stress, respectively. Cell viability was measured using the CellTiter-Glo survival assay. Selected “hits” were subjected to further dose-response testing, and their ability to modulate expression of UPR and oxidative stress markers was assessed by RT-PCR, Western blot, and measurement of protein carbonyl and 8-hydroxydeoxyguanosine (8-OHdG) adducts in immortalized human corneal endothelial cells (iHCECs). Results Forty-one drugs at 20 μM and 55 drugs at 100 μM increased survival of H2O2-challenged cells, and 8 drugs at 20 μM and 2 drugs at 100 μM increased survival of thapsigargin-challenged cells, compared with untreated control cells. Nicergoline, ergothioneine, nimesulide, oxotremorine, and mefenamic acid increased survival of both H2O2- and thapsigargin-challenged cells. Oxotremorine altered DNA damage inducible 3 (CHOP) gene expression, glucose-regulated protein 78 kDa (GRP78) and activating transcription factor 4 (ATF4) protein expression, and protein carbonyl and 8-OHdG levels. Mefenamic acid altered GRP78 protein expression and protein carbonyl and 8-OHdG levels. Conclusions Oxotremorine and mefenamic acid are potential survival factors for corneal endothelial cells under UPR and oxidative stress. The described assay can be further expanded to screen additional drugs for potential therapeutic effect in corneal endothelial diseases such as Fuchs' endothelial corneal dystrophy. DA - 2017/02// PY - 2017 DO - 10.1167/iovs.16-20147 DP - PubMed Central VL - 58 IS - 2 SP - 892 EP - 900 J2 - Invest Ophthalmol Vis Sci SN - 0146-0404 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5295784/ Y2 - 2018/03/13/16:30:52 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5295784/pdf/i1552-5783-58-2-892.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5295784/ ER - TY - JOUR TI - Fuchs endothelial corneal dystrophy: current perspectives AU - Vedana, Gustavo AU - Villarreal, Guadalupe AU - Jun, Albert S T2 - Clinical Ophthalmology (Auckland, N.Z.) AB - Fuchs endothelial corneal dystrophy (FECD) is the most common corneal dystrophy and frequently results in vision loss. Hallmarks of the disease include loss of corneal endothelial cells and formation of excrescences of Descemet’s membrane. Later stages involve all layers of the cornea. Impairment of endothelial barrier and pump function and cell death from oxidative and unfolded protein stress contribute to disease progression. The genetic basis of FECD includes numerous genes and chromosomal loci, although alterations in the transcription factor 4 gene are associated with the majority of cases. Definitive treatment of FECD is corneal transplantation. In this paper, we highlight advances that have been made in understanding FECD’s clinical features, pathophysiology, and genetics. We also discuss recent advances in endothelial keratoplasty and potential future treatments. DA - 2016/02/18/ PY - 2016 DO - 10.2147/OPTH.S83467 DP - PubMed Central VL - 10 SP - 321 EP - 330 J2 - Clin Ophthalmol SN - 1177-5467 ST - Fuchs endothelial corneal dystrophy UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4762439/ Y2 - 2018/03/13/16:29:26 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4762439/pdf/opth-10-321.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4762439/ ER - TY - JOUR TI - The Ultrastructures and Mechanical Properties of the Descement’s Membrane in Fuchs Endothelial Corneal Dystrophy AU - Xia, Dan AU - Zhang, Shuai AU - Nielsen, Esben AU - Ivarsen, Anders Ramløv AU - Liang, Chunyong AU - Li, Qiang AU - Thomsen, Karen AU - Hjortdal, Jesper Østergaard AU - Dong, Mingdong T2 - Scientific Reports AB - Fuchs endothelial corneal dystrophy (FECD), is the most common corneal endothelial dystrophy, and contributes up to 50% of all corneal transplantations performed in developed countries. FECD develops in Descemet’s membrane (DM) and possibly alters the mechanical properties and internal structures in this basal lamina. In this work, the morphology and mechanical properties of FECD-DMs are studied by transmission electron microscopy (TEM) and quantitative dynamic atomic force microscopy (QD-AFM) at nano scale. Pathological wide-space collagens that are typical of FECD display different mechanical properties in that they are softer than the remaining tissue both for dehydrated- and fully hydrated samples. Additionally, the hydration level has major influence on the mechanical properties. These findings could help to further understand the structural changes in FECD, and possibly be useful for further characterization of the disease, the diagnosis and assessment or even pathologic analysis. DA - 2016/03/16/ PY - 2016 DO - 10.1038/srep23096 DP - www.nature.com VL - 6 SP - 23096 LA - en SN - 2045-2322 UR - https://www.nature.com/articles/srep23096 Y2 - 2018/03/13/16:27:02 L1 - https://www.nature.com/articles/srep23096.pdf L2 - https://www.nature.com/articles/srep23096 ER - TY - JOUR TI - Corneal endothelium in patients with diabetes mellitus: a historical cohort study AU - Shenoy, Radha AU - Khandekar, Rajeev AU - Bialasiewicz, Alexander AU - Al Muniri, Abdullah T2 - European Journal of Ophthalmology AB - PURPOSE: Retinopathy is the major cause of ocular morbidity in patients with diabetes mellitus. Chronic hyperglycemia spares no organ and can affect the morphology and function of the various corneal layers, compromising its transparency. This study was conducted to associate the status of corneal endothelium to diabetes mellitus (DM) and identify risk factors of compromised corneal endothelium. METHODS: A total of 220 eyes of randomly selected patients (110 diabetic and 110 nondiabetic) were subjected to detailed slitlamp and fundus evaluation. Corneal endothelial status was evaluated using the Nidek Confoscan 2. Cell density, percentage polymegathism, and pleomorphism were calculated. The findings in diabetic patients were compared to those without disease. The outcome was correlated to diabetic retinopathy (DR). The effects of hypertension, hyperlipidemia, age, gender, type, duration, glycemic control, and grades of DR was also considered. RESULTS: The mean corneal endothelial cell density was -175 cells/mm2 (95% CI -317 to -33 cells/mm2) less in eyes of diabetic patients. The number of endothelial cells with polymegathism was significantly greater among eyes of diabetic patients. There were less corneal endothelial cells with pleomorphism in nondiabetic patients. Polymegathism and pleomorphism of corneal endothelial cells seems to be positively associated with DM type II. Cell density was significantly lower in eyes with DR than those without DR. CONCLUSIONS: Corneal endothelium in diabetic patients seems to be compromised. Evaluation of corneal endothelium should be part of protocol for eye care of diabetic patients. DA - 2009/06//May- undefined PY - 2009 DP - PubMed VL - 19 IS - 3 SP - 369 EP - 375 J2 - Eur J Ophthalmol LA - eng SN - 1120-6721 ST - Corneal endothelium in patients with diabetes mellitus L2 - http://www.ncbi.nlm.nih.gov/pubmed/19396780 L2 - http://www.ncbi.nlm.nih.gov/pubmed/19396780 KW - Age Factors KW - Blood Glucose KW - Cell Count KW - Cell Shape KW - Corneal Diseases KW - Diabetes Mellitus KW - Diabetic Retinopathy KW - Endothelium, Corneal KW - Female KW - Humans KW - Hyperlipidemias KW - Hypertension KW - Male KW - Microscopy, Confocal KW - Middle Aged KW - Risk Factors KW - Sex Factors ER - TY - JOUR TI - Structure and function of the corneal endothelium in diabetes mellitus type I and type II AU - Larsson, L. I. AU - Bourne, W. M. AU - Pach, J. M. AU - Brubaker, R. F. T2 - Archives of Ophthalmology (Chicago, Ill.: 1960) AB - OBJECTIVE: To measure and compare corneal endothelial morphologic characteristics and function in subjects with diabetes mellitus types I and II. DESIGN: Forty-nine patients with diabetes mellitus type I and 60 patients with diabetes mellitus type II were recruited from the active practice of the Mayo Clinic, Rochester, Minn. Thirty-one normal subjects, divided by age into two overlapping groups of 20 each, served as controls. Corneal endothelial permeability and corneal autofluorescence were measured by fluorophotometry. Central corneal endothelial photographs were taken with a wide-field specular microscope, which also measured the corneal thickness. RESULTS: Neither the type I nor the type II diabetics differed from their controls in endothelial permeability and endothelial cell density. The type I diabetics had polymegethism, pleomorphism, increased corneal thickness, and increased corneal autofluorescence compared with their controls. Similar measured values were found in the type II diabetics, but they did not differ significantly from those of their age-matched controls. The type II diabetics were older than the type I diabetics, and the older control group showed changes similar to those seen in the diabetics; these changes were presumably associated with aging. The severity of retinopathy was significantly correlated only with corneal autofluorescence. CONCLUSION: The corneas of patients with type I diabetes mellitus exhibit abnormalities in endothelial cell morphologic characteristics and corneal autofluorescence. The changes resemble those that occur with aging in normal subjects, making them difficult to discern as abnormal in type II diabetics, who are usually older. We found no abnormalities in endothelial permeability in either type I or type II diabetics. DA - 1996/01// PY - 1996 DP - PubMed VL - 114 IS - 1 SP - 9 EP - 14 J2 - Arch. Ophthalmol. LA - eng SN - 0003-9950 L2 - http://www.ncbi.nlm.nih.gov/pubmed/8540858 KW - Adolescent KW - Adult KW - Aged KW - Aged, 80 and over KW - Aging KW - Cell Count KW - Cell Membrane Permeability KW - Diabetes Mellitus, Type 1 KW - Diabetes Mellitus, Type 2 KW - Diabetic Retinopathy KW - Endothelium, Corneal KW - Fluorescein KW - Fluoresceins KW - Fluorophotometry KW - Humans KW - Middle Aged ER - TY - JOUR TI - Matrix metalloproteinase activity is enhanced during corneal wound repair in high glucose condition AU - Takahashi, Hiroshi AU - Akiba, Kiyoshi AU - Noguchi, Takayasu AU - Ohmura, Takeo AU - Takahashi, Ryoki AU - Ezure, Youji AU - Ohara, Kunitoshi AU - Zieske, James D. T2 - Current Eye Research AB - Purpose. (1) To investigate the effect of elevated extracellular glucose on migration, proliferation, and the activity of matrix metalloproteinases (MMPs) of SV40-transformed human corneal epithelial cells (HCEC). (2) To examine MMP activity in wounded corneal epithelium in diabetic rats. Methods. HCEC were cultured in media containing 5.5 mM or 31.2 mM D-glucose, or in a combination of 5.5 mM D-glucose and 25.7 mM D-mannitol on fibronectin/collagen I-coated 48-well plates. After reaching confluence (day 0), cells in the central part of the plate were wounded and the residual cells were cultured for 3 days. Migration and proliferation were evaluated by assessing the increasing amount of area covered by cells, and the day-3 to day-0 ratio of DNA levels, respectively. To determine MMP activity, cells were reacted with synthetic fluorogenic substrates specific to MMPs 1, 2, 3, 7, 9, and MMP activity was determined by a fluorometric kinetic assay. Diabetic rats were induced by streptozotocin injection. Corneal epithelium was scraped from limbus-to-limbus and allowed to heal. Normal rats were treated similarly to serve as controls. Healing epithelium was collected 24 hours later, and gelatin zymography was performed. Results. In the cell culture study, migration in 31.2 mM glucose was significantly slower than that in 5.5 mM, but proliferation in each concentration was similar. The osmotic effect of D-mannitol did not alter migration or proliferation. MMP activity in 31.2 mM was significantly higher than that in 5.5 mM. Zymography revealed enhanced activity of pro and active MMP-9 in healing corneal epithelium in diabetic rats. Conclusions. MMP activity was enhanced in healing corneal epithelium, both in in vitro and in vivo diabetic models, suggesting its involvement in diabetic keratopathy. DA - 2000/01/01/ PY - 2000 DO - 10.1076/0271-3683(200008)2121-VFT608 DP - Taylor and Francis+NEJM VL - 21 IS - 2 SP - 608 EP - 615 SN - 0271-3683 UR - https://www.tandfonline.com/doi/abs/10.1076/0271-3683%28200008%292121-VFT608 Y2 - 2018/03/13/11:27:30 L2 - https://www.tandfonline.com/doi/abs/10.1076/0271-3683(200008)2121-VFT608 ER - TY - JOUR TI - The effects of aldose reductase inhibitor on the corneal endothelial morphology in diabetic rats AU - Matsuda, Mamoru AU - Awata, Takashi AU - Ohashi, Yuichi AU - Inaba, Masamaru AU - Fukuda, Masakatsu AU - Manabe, Reizo T2 - Current Eye Research AB - Diabetic rats were produced by intravenous injection of streptozotocin. Of these, eleven rats were treated with topical instillation of 0.5% aldose reductase inhibitor (ARI), while ten received vehicle alone. The corneal endothelium of these diabetic rats was examined by specular microscopy and compared to age-matched nondiabetic rats (ten rats). Computerized morphometric analysis of individual cells demonstrated that the endothelium of the untreated diabetic rats had marked polymegathism (increased coefficient of variation in cell area) and pleomorphism (decreased percentage of hexagonal cells), as previously observed in diabetic patients. Similar endothelial changes were also noted in the ARI-treated diabetic rats, but to a significantly lesser extent.These results suggest that topically applied ARI can be effective in reducing morphologic changes of the diabetic endotheliura, and that activation of the sorbitol pathway may be implicated in the etiology of such endothelial changes. DA - 1987/01/01/ PY - 1987 DO - 10.3109/02713688709025192 DP - Taylor and Francis+NEJM VL - 6 IS - 2 SP - 391 EP - 397 SN - 0271-3683 UR - https://doi.org/10.3109/02713688709025192 Y2 - 2018/03/13/11:25:01 L2 - https://www.tandfonline.com/doi/abs/10.3109/02713688709025192 ER - TY - JOUR TI - Aldose Reductase Inhibition Suppresses Oxidative Stress-Induced Inflammatory Disorders AU - Srivastava, Satish K AU - Yadav, Umesh C S AU - Reddy, Aramati BM AU - Saxena, Ashish AU - Tammali, Ravinder AU - Mohammad, Shoeb AU - Ansari, Naseem H AU - Bhatnagar, Aruni AU - Petrash, Mark J AU - Srivastava, Sanjay AU - Ramana, Kota V T2 - Chemico-biological interactions AB - Oxidative stress-induced inflammation is a major contributor to several disease conditions including sepsis, carcinogenesis and metastasis, diabetic complications, allergic asthma, uveitis and after cataract surgery posterior capsular opacification. Since reactive oxygen species (ROS)-mediated activation of redox-sensitive transcription factors and subsequent expression of inflammatory cytokines, chemokines and growth factors are characteristics of inflammatory disorders, we envisioned that by blocking the molecular signals of ROS that activate redox-sensitive transcription factors, various inflammatory diseases could be ameliorated. We have indeed demonstrated that ROS –induced lipid peroxidation-derived lipid aldehydes such as 4-hydroxy-trans-2-nonenal (HNE) and their glutathione-conjugates (e.g. GS-HNE) are efficiently reduced by aldose reductase to corresponding alcohols which mediate the inflammatory signals. Our results showed that inhibition of aldose reductase (AKR1B1) significantly prevented the inflammatory signals induced by cytokines, growth factors, endotoxins, high glucose, allergens and auto-immune reactions in cellular as well as animal models. We have demonstrated that AKR1B1 inhibitor, fidarestat, significantly prevents tumor necrosis factor-alpha (TNF-α)-, growth factors-, lipopolysachharide (LPS)-, and environmental allergens-induced inflammatory signals that cause various inflammatory diseases. In animal models of inflammatory diseases such as diabetes, cardiovascular, uveitis, asthma, and cancer (colon, breast, prostate and lung) and metastasis, inhibition of AKR1B1 significantly ameliorated the disease. Our results from various cellular and animal models representing a number of inflammatory conditions suggest that ROS-induced inflammatory response could be reduced by inhibition of AKR1B1, thereby decreasing the progression of the disease and if the therapy is initiated early, the disease could be eliminated. Since fidarestat has already undergone phase III clinical trial for diabetic neuropathy and found to be safe, though clinically not very effective, our results indicate that it can be developed for the therapy of a number of inflammation- related diseases. Our results thus offer a novel therapeutic approach to treat a wide array of inflammatory diseases. DA - 2011/05/30/ PY - 2011 DO - 10.1016/j.cbi.2011.02.023 DP - PubMed Central VL - 191 IS - 1-3 SP - 330 EP - 338 J2 - Chem Biol Interact SN - 0009-2797 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3103634/ Y2 - 2018/03/13/11:23:25 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3103634/pdf/nihms285223.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3103634/ ER - TY - CHAP TI - The Cornea in Diabetes Mellitus AU - Hasan, S. Akbar T2 - Diabetic Retinopathy AB - Although the cornea may appear disease free in the diabetic, marked biochemical and ultrastructural abnormalities are present altering form and function. Awareness of these manifestations of corneal disease in diabetes can lead to steps that prevent more overt complications. DA - 2010/// PY - 2010 DP - link.springer.com SP - 347 EP - 355 LA - en PB - Springer, New York, NY SN - 978-0-387-85899-9 978-0-387-85900-2 UR - https://link.springer.com/chapter/10.1007/978-0-387-85900-2_12 Y2 - 2018/03/13/11:21:29 L2 - https://link.springer.com/chapter/10.1007%2F978-0-387-85900-2_12 ER - TY - JOUR TI - Inflammatory cytokines induce apoptosis of corneal endothelium through nitric oxide AU - Sagoo, Pervinder AU - Chan, Giulia AU - Larkin, Daniel F. P. AU - George, Andrew J. T. T2 - Investigative Ophthalmology & Visual Science AB - PURPOSE: Proinflammatory cytokines are integral components of the allogeneic response to a corneal transplant and contribute to the pathogenesis of graft failure that results from irreversible damage to donor corneal endothelium. As yet, the mechanism and effectors of tissue damage during graft rejection remain unidentified. In the current study, the synergistic apoptotic effect of sustained proinflammatory cytokine insult was investigated in excised cornea and in transformed and primary corneal endothelial cells. METHODS: Apoptosis was assessed by tissue- and flow cytometry-based TUNEL staining. Downstream signaling events of cytokine stimulation and subsequent activation status of endothelium were studied by RT-PCR and Western blot analysis. Cellular production of NO was examined by the Griess reaction. RESULTS: Prolonged exposure (48 hours) of corneal endothelium to IL-1, IFNgamma, and TNF (100 ng/mL each) resulted in induction of apoptosis. Synergy in induction of apoptosis was found after exposure to cytokine combinations. Cytokine-mediated cytotoxicity was correlated with high and sustained (up to 36 hours) endothelial activation (specifically through NF-kappaB, p38, and STAT-1), upregulation of inducible nitric oxide synthase (iNOS), and elevated de novo production of NO. Pharmacologic inhibition of iNOS elicited complete cytoprotection from inflammatory cytokine insult. CONCLUSIONS: The specific release of proinflammatory cytokines from alloreactive infiltrating cells, in combination with the inflamed environment of a corneal allograft, results in apoptosis in the corneal endothelium. This effect is mediated by the de novo generation of NO and sustained activation of NF-kappaB, p38, and STAT-1. Inflammatory cytokine-induced apoptosis presents a new target for the development of interventions to prevent or attenuate endothelial injury in graft rejection. DA - 2004/11// PY - 2004 DO - 10.1167/iovs.04-0439 DP - PubMed VL - 45 IS - 11 SP - 3964 EP - 3973 J2 - Invest. Ophthalmol. Vis. Sci. LA - eng SN - 0146-0404 L2 - http://www.ncbi.nlm.nih.gov/pubmed/15505043 KW - Animals KW - Apoptosis KW - Blotting, Western KW - Cell Line, Transformed KW - DNA-Binding Proteins KW - Endothelium, Corneal KW - Flow Cytometry KW - In Situ Nick-End Labeling KW - Interferon-gamma KW - Interleukin-1 KW - Mice KW - Mice, Inbred BALB C KW - NF-kappa B KW - Nitric Oxide KW - Nitric Oxide Synthase KW - Nitric Oxide Synthase Type II KW - p38 Mitogen-Activated Protein Kinases KW - Reverse Transcriptase Polymerase Chain Reaction KW - STAT1 Transcription Factor KW - Trans-Activators KW - Tumor Necrosis Factor-alpha KW - Up-Regulation ER - TY - ELEC TI - Apoptosis in the Endothelium of Human Corneas for Transplantation | IOVS | ARVO Journals UR - http://iovs.arvojournals.org/article.aspx?articleid=2123710 Y2 - 2018/03/13/10:56:53 L2 - http://iovs.arvojournals.org/article.aspx?articleid=2123710 ER - TY - JOUR TI - Mitochondrial function in apoptotic neuronal cell death. AU - Haeberlein, S. L. T2 - Neurochemical research AB - Abstract: Apoptosis can be defined as the regulated death of a cell and is conducted by conserved pathways. Apoptosis of neurons after injury or disease... DA - 2004/03// PY - 2004 DO - 10.1023/B:NERE.0000014823.74782.b7 DP - europepmc.org VL - 29 IS - 3 SP - 521 EP - 530 J2 - Neurochem Res LA - eng SN - 0364-3190 UR - http://europepmc.org/abstract/med/15038600 Y2 - 2018/03/13/10:52:41 L2 - http://www.ncbi.nlm.nih.gov/pubmed/15038600 L2 - http://europepmc.org/abstract/med/15038600 ER - TY - ELEC TI - Antioxidant Delivery Pathways in the Anterior Eye AU - Umapathy, Ankita AU - Donaldson, Paul AU - Lim, Julie T2 - BioMed Research International AB - Tissues in the anterior segment of the eye are particular vulnerable to oxidative stress. To minimise oxidative stress, ocular tissues utilise a range of antioxidant defence systems which include nonenzymatic and enzymatic antioxidants in combination with repair and chaperone systems. However, as we age our antioxidant defence systems are overwhelmed resulting in increased oxidative stress and damage to tissues of the eye and the onset of various ocular pathologies such as corneal opacities, lens cataracts, and glaucoma. While it is well established that nonenzymatic antioxidants such as ascorbic acid and glutathione are important in protecting ocular tissues from oxidative stress, less is known about the delivery mechanisms used to accumulate these endogenous antioxidants in the different tissues of the eye. This review aims to summarise what is currently known about the antioxidant transport pathways in the anterior eye and how a deeper understanding of these transport systems with respect to ocular physiology could be used to increase antioxidant levels and delay the onset of eye diseases. DA - 2013/// PY - 2013 LA - en M3 - Research article UR - https://www.hindawi.com/journals/bmri/2013/207250/ Y2 - 2018/03/13/10:44:40 L1 - http://downloads.hindawi.com/journals/bmri/2013/207250.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/24187660 L4 - https://www.hindawi.com/journals/bmri/2013/207250/ ER - TY - JOUR TI - Corneal endothelium transports fluid in the absence of net solute transport AU - Diecke, Friedrich P. J. AU - Ma, Li AU - Iserovich, Pavel AU - Fischbarg, Jorge T2 - Biochimica et Biophysica Acta (BBA) - Biomembranes AB - The corneal endothelium transports fluid from the corneal stroma to the aqueous humor, thus maintaining stromal transparency by keeping it relatively dehydrated. This fluid transport mechanism is thought to be driven by the transcellular transports of HCO3− and Cl− in the same direction, from stroma to aqueous. In parallel to these anion movements, for electroneutrality, there are paracellular Na+ and transcellular K+ transports in the same direction. The resulting net flow of solute might generate local osmotic gradients that drive fluid transport. However, there are reports that some 50% residual fluid transport remains in nominally HCO3− free solutions. We have examined the driving force for this residual fluid transport. We confirm that in nominally HCO3− free solutions, 48% of control fluid transport remains. When in addition Cl− channels are inhibited, 30% of control fluid movement still remains. Addition of a carbonic anhydrase inhibitor has no further effect. These manipulations combined inhibit the transcellular transport of all anions, without which there cannot be any net transport of solute and consequently no local osmotic gradients, yet there is residual fluid movement. Only the further addition of benzamil, an inhibitor of epithelial Na+ channels, abolishes fluid transport completely. Our data are inconsistent with transcellular local osmosis and instead support the paradigm of paracellular fluid transport driven by electro-osmotic coupling. DA - 2007/09/01/ PY - 2007 DO - 10.1016/j.bbamem.2007.05.020 DP - ScienceDirect VL - 1768 IS - 9 SP - 2043 EP - 2048 J2 - Biochimica et Biophysica Acta (BBA) - Biomembranes SN - 0005-2736 UR - http://www.sciencedirect.com/science/article/pii/S0005273607001800 Y2 - 2018/03/13/09:24:30 L1 - https://ac.els-cdn.com/S0005273607001800/1-s2.0-S0005273607001800-main.pdf?_tid=51e483a4-8c92-40f3-90b2-e2c7780077a6&acdnat=1520933249_9d2f9b650921d2d4b3d2716e5f6d3475 L2 - https://www.sciencedirect.com/science/article/pii/S0005273607001800 ER - TY - THES TI - Estudio anatomo-clínico y epidemiológico de la queratitis laminar difusa como complicación postquirúrgica de la fotoqueratomileusis (lasik) AU - Cuadrado Escamilla, José Luis CY - Valencia DA - 2009/// PY - 2009 DP - Open WorldCat LA - Spanish PB - Universitat de València, Servei de Publicacions ER - TY - JOUR TI - Alterations of Glutamate, Glutamine, and Related Amino Acids in the Anterior Eye Secondary to Ischaemia and Reperfusion AU - Hu, Rebecca G. AU - Zhu, Yuan AU - Donaldson, Paul AU - Kalloniatis, Michael T2 - Current Eye Research AB - Purpose: To assess the amino acid levels of the ciliary epithelium, aqueous and lens under normal conditions and secondary to ischaemia and reperfusion.Methods: We assessed the amino acids glutamate, glutamine, aspartate, alanine, gamma-amino butyric acid, glycine, arginine and taurine in albino Sprague–Dawley rats. Acute ischaemia was created in the eye and the different anterior eye components were assessed for amino acid levels. Quantitative immunocytochemistry was used to compare amino acid profiles within the ciliary processes immediately after ischaemia and after 4 days of reperfusion. Liquid chromatography was used to determine amino acid levels in the aqueous humour and quantitative immunocytochemistry to determine the location and alterations of amino acids in the lens 4 days after ischaemia/reperfusion.Results: Elevated amino acid levels were evident in the ciliary epithelium immediately after ischaemia. After 4 days of reperfusion, decreased levels of glutamine, gamma-aminobutyric acid, glycine and arginine were evident in the ciliary epithelium, in particular the nonpigmented epithelial cells. The amino acid levels in the aqueous humour remained unchanged after ischaemia/reperfusion and thus showed considerable resilience to this kind of injury. However, significant reductions of glutamate, glutamine, alanine, glycine, arginine and taurine were observed in the lens 4 days after ischaemia/reperfusion.Conclusions: We propose a model to explain the maintenance of amino acid homeostasis in the aqueous humour despite altered levels in both the ciliary processes and lens. DA - 2012/07/01/ PY - 2012 DO - 10.3109/02713683.2012.669509 DP - Taylor and Francis+NEJM VL - 37 IS - 7 SP - 633 EP - 643 SN - 0271-3683 UR - https://doi.org/10.3109/02713683.2012.669509 Y2 - 2018/03/13/09:09:11 L2 - https://www.tandfonline.com/doi/abs/10.3109/02713683.2012.669509?scroll=top&needAccess=true&journalCode=icey20 KW - Amino acid KW - Aqueous humour KW - Ciliary body KW - Immunocytochemistry KW - Ischaemia KW - Lens KW - Reperfusion ER - TY - JOUR TI - EGF suppresses hydrogen peroxide induced Ca2+ influx by inhibiting L-type channel activity in cultured human corneal endothelial cells AU - Mergler, Stefan AU - Pleyer, Uwe AU - Reinach, Peter AU - Bednarz, Jürgen AU - Dannowski, Haike AU - Engelmann, Katrin AU - Hartmann, Christian AU - Yousif, Tarik T2 - Experimental Eye Research AB - Endogenous generated hydrogen peroxide during eye bank storage limits viability. We determined in cultured human corneal endothelial cells (HCEC) whether: (1) this oxidant induces elevations in intracellular calcium concentration [Ca2+]i; (2) epidermal growth factor (EGF) medium supplementation has a protective effect against peroxide mediated rises in [Ca2+]i. Whereas pathophysiological concentrations of H2O2 (10 mM) induced irreversible large increases in [Ca2+]i, lower concentrations (up to 1 mM) had smaller effects, which were further reduced by exposure to either 5 microM nifedipine or EGF (10 ng ml(-1)). EGF had a larger protective effect against H2O2-induced rises in [Ca2+]i than nifedipine. In addition, icilin, the agonist for the temperature sensitive transient receptor potential protein, TRPM8, had complex dose-dependent effects (i.e. 10 and 50 microM) on [Ca2+]i. At 10 microM, it reversibly elevated [Ca2+]i whereas at 50 microM an opposite effect occurred suggesting complex effects of temperature on endothelial viability. Taken together, H2O2 induces rises in [Ca2+]i that occur through increases in Ca2+ permeation along plasma membrane pathways that include L-type Ca2+ channels as well as other EGF-sensitive pathways. As EGF overcomes H2O2-induced rises in [Ca2+]i, its presence during eye bank storage could improve the outcome of corneal transplant surgery. DA - 2005/02// PY - 2005 DO - 10.1016/j.exer.2004.09.012 DP - PubMed VL - 80 IS - 2 SP - 285 EP - 293 J2 - Exp. Eye Res. LA - eng SN - 0014-4835 L2 - http://www.ncbi.nlm.nih.gov/pubmed/15670807 KW - Calcium KW - Calcium Channels, L-Type KW - Cell Line KW - Cold Temperature KW - Dose-Response Relationship, Drug KW - Endothelial Cells KW - Endothelium, Corneal KW - Epidermal Growth Factor KW - Humans KW - Hydrogen Peroxide KW - Oxidants ER - TY - JOUR TI - Glutaminolysis is Essential for Energy Production and Ion Transport in Human Corneal Endothelium AU - Zhang, Wenlin AU - Li, Hongde AU - Ogando, Diego G. AU - Li, Shimin AU - Feng, Matthew AU - Price, Francis W. AU - Tennessen, Jason M. AU - Bonanno, Joseph A. T2 - EBioMedicine AB - Corneal endothelium (CE) is among the most metabolically active tissues in the body. This elevated metabolic rate helps the CE maintain corneal transparency by its ion and fluid transport properties, which when disrupted, leads to visual impairment. Here we demonstrate that glutamine catabolism (glutaminolysis) through TCA cycle generates a large fraction of the ATP needed to maintain CE function, and this glutaminolysis is severely disrupted in cells deficient in NH3:H+cotransporter Solute Carrier Family 4 Member 11 (SLC4A11). Considering SLC4A11 mutations leads to corneal endothelial dystrophy and sensorineural deafness, our results indicate that SLC4A11-associated developmental and degenerative disorders result from altered glutamine catabolism. Overall, our results describe an important metabolic mechanism that provides CE cells with the energy required to maintain high level transport activity, reveal a direct link between glutamine metabolism and developmental and degenerative neuronal diseases, and suggest an approach for protecting the CE during ophthalmic surgeries. DA - 2017/02// PY - 2017 DO - 10.1016/j.ebiom.2017.01.004 DP - PubMed VL - 16 SP - 292 EP - 301 J2 - EBioMedicine LA - eng SN - 2352-3964 L2 - http://www.ncbi.nlm.nih.gov/pubmed/28117276 KW - Adenosine Triphosphate KW - Amino Acid Transport System X-AG KW - Animals KW - Carrier Proteins KW - Cell Line KW - Cells, Cultured KW - Citric Acid Cycle KW - Congenital hereditary endothelial dystrophy (CHED) KW - Corneal Dystrophies, Hereditary KW - Corneal endothelium KW - Endothelium, Corneal KW - Energy metabolism KW - Energy Metabolism KW - Epithelium, Corneal KW - Fuchs' endothelial corneal dystrophy (FECD) KW - Fuchs' Endothelial Dystrophy KW - Gene Expression KW - Glutamine KW - Glutaminolysis KW - Humans KW - Ion Transport KW - Mice, Knockout KW - Microscopy, Fluorescence KW - Mutation KW - Rabbits KW - Reverse Transcriptase Polymerase Chain Reaction KW - SLC4A Proteins KW - SLC4A11 ammonia transporter ER - TY - JOUR TI - Oxygen consumption of the rabbit cornea. AU - Harvitt, D. M. AU - Bonanno, J. A. T2 - Investigative Ophthalmology & Visual Science DA - 1998/02/01/ PY - 1998 DP - iovs.arvojournals.org VL - 39 IS - 2 SP - 444 EP - 448 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?articleid=2181302 Y2 - 2018/03/13/08:47:43 L1 - http://iovs.arvojournals.org/data/journals/iovs/933427/444.pdf L2 - http://iovs.arvojournals.org/article.aspx?articleid=2181302&resultClick=1 ER - TY - JOUR TI - Oxidative Stress in the Pathogenesis of Keratoconus and Fuchs Endothelial Corneal Dystrophy AU - Wojcik, Katarzyna A. AU - Kaminska, Anna AU - Blasiak, Janusz AU - Szaflik, Jerzy AU - Szaflik, Jacek P. T2 - International Journal of Molecular Sciences AB - Due to its localization and function, the cornea is regularly exposed to sunlight and atmospheric oxygen, mainly dioxygen, which produce reactive oxygen species (ROS). Therefore, corneal cells are particularly susceptible to oxidative stress. The accumulation of ROS in the cornea may affect signal transduction, proliferation and may also promote cell death. The cornea has several enzymatic and non-enzymatic antioxidants involved in ROS scavenging, but in certain conditions they may not cope with oxidative stress, leading to diseases of the eye. Keratoconus (KC) and Fuchs endothelial corneal dystrophy (FECD) are multifactorial diseases of the cornea, in which pathogenesis is not fully understood. However, increased levels of oxidative stress markers detected in these disorders indicate that oxidative stress may play an important role in their development and progression. These markers are: (i) decreased levels of non-enzymatic antioxidants, and (ii) decreased expression of genes encoding antioxidative enzymes, including thioredoxin reductase, peroxiredoxins, superoxide dismutase, glutathione S-transferase, and aldehyde dehydrogenase. Moreover, the FECD endothelium displays higher levels of oxidative DNA damage, especially in mitochondrial DNA (mtDNA), whereas KC cornea shows abnormal levels of some components of oxidative phosphorylation encoded by mtDNA. In this review we present some considerations and results of experiments supporting the thesis on the important role of oxidative stress in KC and FECD pathology. DA - 2013/09/23/ PY - 2013 DO - 10.3390/ijms140919294 DP - PubMed Central VL - 14 IS - 9 SP - 19294 EP - 19308 J2 - Int J Mol Sci SN - 1422-0067 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3794834/ Y2 - 2018/03/13/04:51:53 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3794834/pdf/ijms-14-19294.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3794834/ ER - TY - JOUR TI - Biology of the corneal endothelium in health and disease AU - Bourne, W. M. T2 - Eye (London, England) DA - 2003/11// PY - 2003 DO - 10.1038/sj.eye.6700559 DP - PubMed VL - 17 IS - 8 SP - 912 EP - 918 J2 - Eye (Lond) LA - eng SN - 0950-222X L2 - http://www.ncbi.nlm.nih.gov/pubmed/14631396 KW - Aged KW - Contact Lenses KW - Corneal Diseases KW - Endothelium, Corneal KW - Female KW - Humans KW - Keratoplasty, Penetrating KW - Male KW - Middle Aged ER - TY - JOUR TI - [Study of the corneal endothelium after glaucoma surgery] AU - Lázaro, C. García AU - Castillo, A. Gómez AU - García, J. Feijóo AU - Macías, JM Benítez AU - García, J. Sánchez T2 - Archivos de la Sociedad Espanola de Oftalmologia AB - Abstract: PURPOSE: To analyze the changes suffered by corneal endothelium in patients who underwent a macrotrabeculectomy. METHODS: A prospective study was... DA - 2000/02// PY - 2000 DP - europepmc.org VL - 75 IS - 2 SP - 75 EP - 80 J2 - Arch Soc Esp Oftalmol LA - spa SN - 0365-6691 UR - http://europepmc.org/abstract/med/11151123 Y2 - 2018/03/13/02:12:49 L2 - http://www.ncbi.nlm.nih.gov/pubmed/11151123 L2 - http://europepmc.org/abstract/med/11151123 ER - TY - JOUR TI - Corneal endothelial cell damage by free radicals associated with ultrasound oscillation AU - Murano, Nao AU - Ishizaki, Masamichi AU - Sato, Shigeru AU - Fukuda, Yuh AU - Takahashi, Hiroshi T2 - Archives of Ophthalmology (Chicago, Ill.: 1960) AB - OBJECTIVE: To determine whether ultrasound oscillations in the anterior chamber cause corneal endothelial injury by free radicals. METHODS: A phacoemulsification probe was introduced into the anterior chamber of rabbits' eyes through a limbal incision, and ultrasound oscillation was performed without emulsifying the lens. Rabbits were assigned to 4 treatment groups: (1) no treatment (controls); (2) only irrigation with a salt solution; (3) ultrasound only; and (4) ultrasound oscillations with a salt solution of 0.001M ascorbic acid. The corneas were immunohistochemically examined for oxidative stress using 8-hydroxy-2-deoxyguanosine (8-OHdG), apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) staining, and ultrastructural changes by electron microscopy. The lipid peroxide levels in the aqueous humor were also measured. RESULTS: In the ultrasound-only group, 8-OHdG-positive cells and TUNEL-positive cells were detected at 24 hours; necrotic cells were detected at 12 to 24 hours. Also, lipid peroxide levels were significantly increased at later times in the ultrasound group. Such changes were not observed in other groups. CONCLUSION: Free radicals induced by ultrasound oscillation can cause corneal endothelial damages. Clinical Relevance Clinicians should be aware that free radicals associated with ultrasound oscillation can injure the corneal endothelial cells. DA - 2008/06// PY - 2008 DO - 10.1001/archopht.126.6.816 DP - PubMed VL - 126 IS - 6 SP - 816 EP - 821 J2 - Arch. Ophthalmol. LA - eng SN - 1538-3601 L2 - http://www.ncbi.nlm.nih.gov/pubmed/18541846 KW - Animals KW - Anterior Chamber KW - Aqueous Humor KW - Deoxyguanosine KW - Endothelium, Corneal KW - Free Radicals KW - Immunohistochemistry KW - In Situ Nick-End Labeling KW - Lipid Peroxides KW - Male KW - Microscopy, Electron KW - Microscopy, Electron, Scanning KW - Necrosis KW - Phacoemulsification KW - Rabbits KW - Time Factors KW - Ultrasonics KW - Up-Regulation ER - TY - JOUR TI - Identity and regulation of ion transport mechanisms in the corneal endothelium AU - Bonanno, Joseph A. T2 - Progress in Retinal and Eye Research AB - Corneal transparency is dependent on regulation of the hydration of the corneal stroma. Water is driven into the cornea across the epithelial and endothelial cell layers by the stromal swelling pressure. This fluid leak into the cornea is counterbalanced by the corneal fluid pump, which is predominantly attributed to the ion and fluid transport capacity of the endothelial cell layer. Primary and secondary active transport mechanisms are responsible for generating a net ion flux from the stromal to anterior chamber side of the endothelium; however, the identity and location of all the components of this transport system are not known. The endothelial fluid pump is dependent on the presence of Cl(-) and HCO(3)(-), and can be slowed by carbonic anhydrase inhibitors. A number of anion transport mechanisms have been identified and characterized in the endothelium, including basolateral Na(+)/2HCO(3)(-) cotransport, Na(+)/K(+)/2Cl(-) cotransport, Cl(-)/HCO(3)(-) exchange, and apical anion channels permeable to both Cl(-) and HCO(3)(-). Furthermore, there is evidence for a carbonic anhydrase mediated CO(2)-diffusive mode of apical HCO(3)(-) flux. These findings are incorporated into a new model of transendothelial anion transport, which suggests that there are a number of alternate pathways for anion transport. There have been few studies on activation of signal transduction pathways that could stimulate endothelial fluid transport. Interestingly, recent studies show that multiple autocrine signaling pathways are in place that could be upregulated during physical stimulation and may be responsible for maintaining basal levels of fluid secretion. DA - 2003/01// PY - 2003 DP - PubMed VL - 22 IS - 1 SP - 69 EP - 94 J2 - Prog Retin Eye Res LA - eng SN - 1350-9462 L2 - http://www.ncbi.nlm.nih.gov/pubmed/12597924 KW - Adenylyl Cyclases KW - Animals KW - Antiporters KW - Carbonic Anhydrases KW - Cell Membrane Permeability KW - Cells, Cultured KW - Chlorides KW - Endothelium, Corneal KW - Epithelial Cells KW - Extracellular Space KW - Homeostasis KW - Humans KW - Hydrogen-Ion Concentration KW - Ion Transport KW - Models, Biological ER - TY - BOOK TI - Clinical Anatomy of the Visual System E-Book AU - Remington, Lee Ann AB - Taking the place of the multiple texts traditionally needed to cover visual anatomy and physiology, Clinical Anatomy and Physiology of the Visual System, 3rd Edition dramatically lightens your load by providing one book that covers it all! This concise, well-referenced resource contains information on the clinical anatomy of the eye, its adnexa and visual pathways, histologic information, plus newly added content on physiology of the human ocular structures. Vivid illustrations complement the text and provide clinical information on diseases and disorders that represent departures from normal clinical anatomy.Comprehensive physiology coverage clarifies the integration between structure and function, eliminating your need for multiple books on the anatomy and physiology of the visual system. An emphasis on clinical application helps you better understand the processes that occur in disease and dysfunction. Genetic information keeps you current with the latest developments in visual anatomy and physiology. Full-color illustrations throughout the text enhance your understanding of anatomical and clinical information. UNIQUE! Clinical Comment sections provide a solid foundation for recognizing and understanding clinical situations, conditions, diseases, and treatments. Photos of normal eye structures illustrate clinical appearance and demonstrate how appearance is directly related to structure. Geriatric coverage, including aging changes in ocular tissue and the visual pathway, keeps you up-to-date with the expanding field of geriatric care. UNIQUE! Expert coverage written by an actual optometrist gives you a practical framework for recognizing and understanding clinical situations, problems, and treatments. DA - 2011/07/29/ PY - 2011 DP - Google Books SP - 303 LA - en PB - Elsevier Health Sciences SN - 978-1-4557-2777-3 L2 - https://books.google.com.co/books?id=Bhf0Fpvq9GMC ER - TY - JOUR TI - Cell Pattern in Adult Human Corneal Endothelium AU - Wörner, Carlos H. AU - Olguín, Alicia AU - Ruíz-García, José L. AU - Garzón-Jiménez, Nuria T2 - PLOS ONE AB - A review of the current data on the cell density of normal adult human endothelial cells was carried out in order to establish some common parameters appearing in the different considered populations. From the analysis of cell growth patterns, it is inferred that the cell aging rate is similar for each of the different considered populations. Also, the morphology, the cell distribution and the tendency to hexagonallity are studied. The results are consistent with the hypothesis that this phenomenon is analogous with cell behavior in other structures such as dry foams and grains in polycrystalline materials. Therefore, its driving force may be controlled by the surface tension and the mobility of the boundaries. DA - 2011/05/13/undefined PY - 2011 DO - 10.1371/journal.pone.0019483 DP - PLoS Journals VL - 6 IS - 5 SP - e19483 J2 - PLOS ONE LA - en SN - 1932-6203 UR - http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0019483 Y2 - 2018/03/11/16:58:12 L1 - http://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0019483&type=printable L2 - http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0019483 ER - TY - JOUR TI - Physiologic changes of the cornea with contact lens wear AU - Liesegang, Thomas J. T2 - The CLAO journal: official publication of the Contact Lens Association of Ophthalmologists, Inc AB - PURPOSE: This article reviews the corneal changes resulting from the hypoxia that occurs during sleep and specifically during contact lens wear. METHODS: Discussion includes a literature review and observations regarding the changes to the corneal epithelium, stroma, and endothelium that take place during sleep and wearing of contact lenses made from different materials. RESULTS: Hypoxia and hypercapnia cause significant changes to the corneal epithelium, stroma, and endothelium. Some of these changes can also be seen following the sleep cycle. Epithelial changes include decreased metabolic rate, morphologic changes, microcysts, changes in junctional integrity, decreased corneal sensation, and pannus formation. Stromal changes include stromal edema, stromal acidosis, neovascularization, and changes in corneal shape and, ultimately, corneal thinning. Endothelial changes include bleb formation, polymegethism, changes in endothelial cell density, and possible changes in endothelial function. CONCLUSIONS: There are multiple and significant corneal changes resulting from hypoxia and hypercapnia. These changes vary with the specific lens style. The high-oxygen-permeable contact lenses recently introduced may overcome some of these problems. DA - 2002/01// PY - 2002 DP - PubMed VL - 28 IS - 1 SP - 12 EP - 27 J2 - CLAO J LA - eng SN - 0733-8902 L2 - http://www.ncbi.nlm.nih.gov/pubmed/11838985 ER - TY - BOOK TI - Gray's anatomy : the anatomical basis of clinical practice AU - , Standring, Susan CY - United States DA - 2016/// PY - 2016 ET - Forty-first edition PB - New York : Elsevier Limited SN - 9780702052309 (main edition) 9780702063060 (international edition paperback) 9780702068515 (PDF, EPUB) 9780702068522 (Inkling interactive ebook) ER - TY - JOUR TI - Descemet-stripping automated endothelial keratoplasty: six-month results in a prospective study of 100 eyes AU - Chen, Edwin S. AU - Terry, Mark A. AU - Shamie, Neda AU - Hoar, Karen L. AU - Friend, Daniel J. T2 - Cornea AB - PURPOSE: To report 6-month results in a large, prospective study of Descemet-stripping automated endothelial keratoplasty (DSAEK). METHODS: A 5-mm scleral-limbal tunnel approach was created for placement of an automated microkeratome-prepared 8.0-mm endothelial graft after DSAEK in 150 consecutive cases between September 2005 and October 2006. Six-month follow-up data were available on 100 eyes. Intraoperative peripheral scraping was performed to promote adherence of the donor. Preoperative and postoperative visual acuity with and without spectacle correction (BSCVA and UCVA), refractive astigmatism, average topographic keratometry, surface asymmetry index, surface regularity index, and pachymetry were measured prospectively. RESULTS: After DSAEK surgery, average BSCVA improved from 20/86 to 20/38, and average UCVA improved from 20/155 to 20/73, which were both statistically significant (P < 0.05). Excluding 26 eyes with known retinal pathology: 97% of the 74 eyes had a vision of 20/40 or better at 6 months and 14% obtained 20/20 or better. Refractive astigmatism changed an average 0.06 D, and average topographic keratometry changed an average -0.13 D, which were not statistically significant. Surface regularity index and surface asymmetry index improved to normal levels of 0.67 and 1.03, respectively (P < 0.001 and P = 0.002). Pachymetry decreased significantly from 0.70 to 0.66 mm (P = .001). CONCLUSIONS: This large prospective study of DSAEK shows that this surgery provides a significant improvement in vision, corneal thickness, and surface regularity. It does not change refractive astigmatism or average topographic keratometry significantly. This newer technique of endothelial keratoplasty yields many of the benefits of its predecessors, deep lamellar endothelial keratoplasty and posterior lamellar keratoplasty, while improving the visual results. DA - 2008/06// PY - 2008 DO - 10.1097/ICO.0b013e3181611c50 DP - PubMed VL - 27 IS - 5 SP - 514 EP - 520 J2 - Cornea LA - eng SN - 1536-4798 ST - Descemet-stripping automated endothelial keratoplasty L2 - http://www.ncbi.nlm.nih.gov/pubmed/18520497 ER - TY - JOUR TI - Prenatal and postnatal cellularity of the human corneal endothelium. A quantitative histologic study AU - Murphy, C. AU - Alvarado, J. AU - Juster, R. AU - Maglio, M. T2 - Investigative Ophthalmology & Visual Science AB - The authors studied the cellularity of the normal corneal endothelium by histologic methods in 56 specimens from 16 weeks of gestation to 98 years of age. Ten step-serial sections were taken from each specimen through the central 6 mm of the cornea, in an area measuring 1.8 mm. The number of nuclei were counted on each section and a ratio of the number of nuclei per 100 micron of endothelial length was determined. This ratio provides a measure of cell density that they call cellularity. There is a decrease in cellularity that proceeds in a nonlinear manner and at a very rapid rate during the prenatal period and for the first few years of life. Cell death or necrosis, which might have contributed to this apparent loss of cells, was not observed. Instead, this rapid change in cellularity is correlated with a concomitant change in corneal size. The authors' calculations show that cell division may play a minor role in the formation of the endothelium after the second trimester of fetal life as most of the cells present by birth already exist by this time. After the first few years of life, the rate of change in endothelial cellularity decreases to proceed in a linear manner for the rest of the near 100 years of life examined. This latter age-related decline in cellularity is probably due to the loss of 0.56% cells per year from the endothelial layer, since the cornea does not appear to change in size during this time. Statistical analysis of the authors' data shows that these results are highly significant. DA - 1984/03// PY - 1984 DP - PubMed VL - 25 IS - 3 SP - 312 EP - 322 J2 - Invest. Ophthalmol. Vis. Sci. LA - eng SN - 0146-0404 L2 - http://www.ncbi.nlm.nih.gov/pubmed/6698749 ER - TY - JOUR TI - The role of apoptosis in the pathogenesis of Fuchs endothelial dystrophy of the cornea AU - Li, Q. J. AU - Ashraf, M. F. AU - Shen, D. F. AU - Green, W. R. AU - Stark, W. J. AU - Chan, C. C. AU - O'Brien, T. P. T2 - Archives of Ophthalmology (Chicago, Ill.: 1960) AB - OBJECTIVE: To investigate the potential role of apoptosis in the pathogenesis of Fuchs endothelial dystrophy of the cornea. METHODS: Twenty-one corneal buttons from patients with Fuchs dystrophy and 15 control corneas were studied. Apoptosis was assessed by the in situ end-labeling of double-stranded DNA breaks, and by immunohistochemical characterization of cellular markers associated with apoptosis (Fas, FasL, Bcl-2, and Bax). Expression of Bcl-2 and Bax mRNA in the corneal stroma and endothelium was separately analyzed by a semiquantitative reverse transcriptase polymerase chain reaction. Furthermore, cultivated keratocytes generated from diseased corneal buttons and donor rims were exposed to camptothecin, an apoptotic inducer, for 6 and 24 hours. They were then examined for protein and messenger RNA (mRNA) expression of apoptotic regulatory molecules. RESULTS: DNA fragmentation was seen in the epithelium, stroma, and endothelium in 6 of 7 corneas with Fuchs dystrophy. A statistically significant difference was identified in the expression of Bax and its mRNA in the stroma, but not in the endothelium of Fuchs dystrophy corneas. Following exposure to camptothecin, keratocytes from patients with Fuchs dystrophy responded with an increased level of Bax and a low level of Bcl-2. This trend was distinctively different from the response of normal keratocytes. CONCLUSIONS: The evidence in this study points to a disease-related disturbance in the regulation of apoptosis in Fuchs dystrophy. Our findings suggest that excessive apoptosis may be an important mechanism in the pathogenesis of Fuchs dystrophy. DA - 2001/11// PY - 2001 DP - PubMed VL - 119 IS - 11 SP - 1597 EP - 1604 J2 - Arch. Ophthalmol. LA - eng SN - 0003-9950 L2 - http://www.ncbi.nlm.nih.gov/pubmed/11709009 ER - TY - JOUR TI - Evaluation of the corneal endothelium in patients with diabetes mellitus type I and II AU - Módis, László AU - Szalai, Eszter AU - Kertész, Katalin AU - Kemény-Beke, Adám AU - Kettesy, Beáta AU - Berta, András T2 - Histology and Histopathology AB - BACKGROUND: The aim of the present study is to determine corneal physiology and endothelial morphology after proper image analysis technique in type I and II diabetic patients. The HbA1c level and the grade of retinopathy were also recorded and correlated with the endothelial parameters. METHODS: 41 eyes of 21 patients with type I and 59 eyes of 30 patients with type II diabetes mellitus (mean age was 40.97 ± 15.46 and 64.36 ± 10.47 years) were examined and compared to age-matched controls. Endothelial cell density (ECD), mean cell area, coefficient of variation of cell area, central corneal thickness, intraocular pressure, and grade of retinopathy were recorded. RESULTS: There was a statistically significant decreased endothelial cell density in type I disease (2428 ± 219 cell/mm2) in comparison with healthy subjects (2495 ± 191 cell/mm2, P=0.02). The diabetic corneas were thicker than normal (P=0.001). The HbA1c level was inversely correlated with the ECD (r=-0.60; P<0.0001) and correlated with the mean endothelial cell area (r=0.60, P<0.0001). Significant correlation was observed between the endothelial morphology and grade of diabetic retinopathy (r=-0.40, ECD; r=0.38, mean cell area; P=0.01 for both). In type II diabetes mellitus no significant difference was found in the evaluated values. CONCLUSIONS: The present study disclosed the alteration of the corneal endothelial morphology in type I diabetes mellitus as compared to normal subjects. The results indicated that type I diabetic corneas are more susceptible to environmental changes than type II corneas. DA - 2010//12/ PY - 2010 DO - 10.14670/HH-25.1531 DP - PubMed VL - 25 IS - 12 SP - 1531 EP - 1537 J2 - Histol. Histopathol. LA - eng SN - 1699-5848 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20886433 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20886433 KW - Adult KW - Blood Glucose KW - Cornea KW - Diabetes Mellitus, Type 1 KW - Diabetes Mellitus, Type 2 KW - Diabetic Retinopathy KW - Endothelial Cells KW - Endothelium, Corneal KW - Female KW - Glycated Hemoglobin A KW - Humans KW - Image Processing, Computer-Assisted KW - Male KW - Middle Aged ER - TY - JOUR TI - Progress in corneal wound healing AU - Ljubimov, Alexander V. AU - Saghizadeh, Mehrnoosh T2 - Progress in Retinal and Eye Research AB - Corneal wound healing is a complex process involving cell death, migration, proliferation, differentiation, and extracellular matrix remodeling. Many similarities are observed in the healing processes of corneal epithelial, stromal and endothelial cells, as well as cell-specific differences. Corneal epithelial healing largely depends on limbal stem cells and remodeling of the basement membrane. During stromal healing, keratocytes get transformed to motile and contractile myofibroblasts largely due to activation of transforming growth factor-β (TGF-β) system. Endothelial cells heal mostly by migration and spreading, with cell proliferation playing a secondary role. In the last decade, many aspects of wound healing process in different parts of the cornea have been elucidated, and some new therapeutic approaches have emerged. The concept of limbal stem cells received rigorous experimental corroboration, with new markers uncovered and new treatment options including gene and microRNA therapy tested in experimental systems. Transplantation of limbal stem cell-enriched cultures for efficient re-epithelialization in stem cell deficiency and corneal injuries has become reality in clinical setting. Mediators and course of events during stromal healing have been detailed, and new treatment regimens including gene (decorin) and stem cell therapy for excessive healing have been designed. This is a very important advance given the popularity of various refractive surgeries entailing stromal wound healing. Successful surgical ways of replacing the diseased endothelium have been clinically tested, and new approaches to accelerate endothelial healing and suppress endothelial-mesenchymal transformation have been proposed including Rho kinase (ROCK) inhibitor eye drops and gene therapy to activate TGF-β inhibitor SMAD7. Promising new technologies with potential for corneal wound healing manipulation including microRNA, induced pluripotent stem cells to generate corneal epithelium, and nanocarriers for corneal drug delivery are discussed. Attention is also paid to problems in wound healing understanding and treatment, such as lack of specific epithelial stem cell markers, reliable identification of stem cells, efficient prevention of haze and stromal scar formation, lack of data on wound regulating microRNAs in keratocytes and endothelial cells, as well as virtual lack of targeted systems for drug and gene delivery to select corneal cells. DA - 2015/11// PY - 2015 DO - 10.1016/j.preteyeres.2015.07.002 DP - PubMed VL - 49 SP - 17 EP - 45 J2 - Prog Retin Eye Res LA - eng SN - 1873-1635 L2 - http://www.ncbi.nlm.nih.gov/pubmed/26197361 ER - TY - JOUR TI - Comprehensive Review of the Effects of Diabetes on Ocular Health AU - Skarbez, Kathryn AU - Priestley, Yos AU - Hoepf, Marcia AU - Koevary, Steven B. T2 - Expert review of ophthalmology DA - 2010/08/01/ PY - 2010 DO - 10.1586/eop.10.44 DP - PubMed Central VL - 5 IS - 4 SP - 557 EP - 577 J2 - Expert Rev Ophthalmol SN - 1746-9899 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3134329/ Y2 - 2018/03/07/16:34:08 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3134329/pdf/nihms286175.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3134329/ ER - TY - JOUR TI - Experimental gene transfer to the corneal endothelium AU - Kampik, D. AU - Ali, R. R. AU - Larkin, D. F. P. T2 - Experimental Eye Research AB - Transfer of cDNA to corneal endothelial cells has been demonstrated in cell monolayers in vitro, in endothelium of whole thickness corneas ex vivo and following intracameral injection. Studies examining the feasibility and optimal methods for gene transfer to the cornea have used viral and non-viral vectors, initially histochemical or fluorescent marker genes, and in endothelium of numerous species ranging from mouse to man. As the feasibility of genetic modification of corneal endothelial cells has been successfully demonstrated in a number of cell culture and animal models, there is significant potential for gene transfer in the treatment of human corneal endothelial disease. The two most widely studied applications of gene transfer to endothelium are (i) transduction of immunomodulatory genes to donor corneal endothelium prior to transplantation as a strategy to delay allogeneic rejection and (ii) modulation of apoptosis or induction of replication in human corneal endothelial cells to increase cell density. Although continued improvements in vectors for gene transfer will improve the efficacy and safety of gene therapy, more detailed understanding of the altered biology of endothelium in disease will be necessary to allow selection of appropriate targets for a gene-based treatment approach. DA - 2012/02// PY - 2012 DO - 10.1016/j.exer.2011.07.001 DP - PubMed VL - 95 IS - 1 SP - 54 EP - 59 J2 - Exp. Eye Res. LA - eng SN - 1096-0007 L2 - http://www.ncbi.nlm.nih.gov/pubmed/21777585 KW - Animals KW - Cornea KW - Corneal Diseases KW - Corneal Transplantation KW - Endothelial Cells KW - Gene Transfer Techniques KW - Genetic Therapy KW - Genetic Vectors KW - Graft Rejection KW - Humans ER - TY - JOUR TI - Semaphorin3A/neuropilin-1 signaling acts as a molecular switch regulating neural crest migration during cornea development AU - Lwigale, Peter Y. AU - Bronner-Fraser, Marianne T2 - Developmental biology AB - Cranial neural crest cells migrate into the periocular region and later contribute to various ocular tissues including the cornea, ciliary body and iris. After reaching the eye, they initially pause before migrating over the lens to form the cornea. Interestingly, removal of the lens leads to premature invasion and abnormal differentiation of the cornea. In exploring the molecular mechanisms underlying this effect, we find that semaphorin3A (Sema3A) is expressed in the lens placode and epithelium continuously throughout eye development. Interestingly, neuropilin-1 (Npn-1) is expressed by periocular neural crest but down-regulated, in a manner independent of the lens, by the subpopulation that migrates into the eye and gives rise to the cornea endothelium and stroma. In contrast, Npn-1 expressing neural crest remain in the periocular region and contribute to the anterior uvea and ocular blood vessels. Introduction of a peptide that inhibits Sema3A/Npn-1 signaling results in premature entry of neural crest cells over the lens that phenocopies lens ablation. Furthermore, Sema3A inhibits periocular neural crest migration in vitro. Taken together, our data reveal a novel and essential role of Sema3A/Npn-1 signaling in coordinating periocular neural crest migration that is vital for proper ocular development. DA - 2009/12/15/ PY - 2009 DO - 10.1016/j.ydbio.2009.10.008 DP - PubMed Central VL - 336 IS - 2 SP - 257 EP - 265 J2 - Dev Biol SN - 0012-1606 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2800376/ Y2 - 2018/04/12/12:59:21 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2800376/pdf/nihms161799.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2800376/ ER - TY - JOUR TI - Corneal development associated with eyelid opening AU - Zieske, James D. T2 - International Journal of Developmental Biology AB - The development of the cornea as a tissue initiates as early as five weeks in the human embryo. This development continues gradually until the time of eyelid opening, which is associated with major developmental changes. These events, most easily observed in rodents, which are born with closed eyelids, include alterations in the rate of cell proliferation in the epithelium, stroma and endothelium; differentiation of the epithelium; appearance of a tear film and tear-film-associated proteins; and swelling and thinning of the stroma. Eyelid opening is also associated with numerous alterations in gene expression. These events are the subject of this review. Readers are directed to the article by Wolosin et al., also in this volume, for an in-depth discussion of early corneal development. DA - 2004/11/01/ PY - 2004 DO - 10.1387/ijdb.041860jz DP - www.ijdb.ehu.es VL - 48 IS - 8-9 SP - 903 EP - 911 J2 - Int. J. Dev. Biol. LA - en SN - 0214-6282, 1696-3547 UR - http://www.ijdb.ehu.es/web/paper/041860jz Y2 - 2018/04/12/12:46:08 L1 - http://www.ijdb.ehu.es/web/descarga/paper/041860jz L2 - http://www.ncbi.nlm.nih.gov/pubmed/15558481 L2 - http://www.ijdb.ehu.es/web/paper/041860jz/corneal-development-associated-with-eyelid-opening- ER - TY - ELEC TI - Voltage-dependent calcium channel, L-type, alpha-1 subunit (IPR005446) < InterPro < EMBL-EBI UR - http://www.ebi.ac.uk/interpro/entry/IPR005446 Y2 - 2018/05/29/13:18:43 L2 - http://www.ebi.ac.uk/interpro/entry/IPR005446 ER - TY - JOUR TI - Emerging functions of pannexin 1 in the eye AU - Kurtenbach, Sarah AU - Kurtenbach, Stefan AU - Zoidl, Georg T2 - Frontiers in Cellular Neuroscience AB - Pannexin 1 (Panx1) is a high-conductance, voltage-gated channel protein found in vertebrates. It has been shown that Panx1 is widely expressed in many organs and tissues, including sensory systems. In the eye, Panx1 is expressed in major divisions including the retina, lens and cornea. Panx1 is found in different neuronal and non-neuronal cell types and localizes in strategic positions. The channel is mechanosensitive, and responds to changes in extracellular ATP, intracellular calcium, pH, or ROS/nitric oxide. Since Panx1 channels operate at the crossroad of major signaling pathways, physiological functions in important autocrine and paracrine feedback signaling mechanisms were hypothesized. This review summarizes known functions and outlines emerging roles of Panx1 in the eye demonstrating that this versatile channel is involved in multiple functions ranging from processing of visual information in the outer retina, to a crosstalk between immune and neural cells, pressure related pathological conditions like glaucoma, wound repair or neuronal cell death caused by ischemia. DA - 2014/// PY - 2014 DO - 10.3389/fncel.2014.00263 DP - Frontiers VL - 8 J2 - Front. Cell. Neurosci. LA - English SN - 1662-5102 UR - https://www.frontiersin.org/articles/10.3389/fncel.2014.00263/full Y2 - 2018/05/29/05:00:47 L1 - https://www.frontiersin.org/articles/10.3389/fncel.2014.00263/pdf KW - ATP KW - Cornea KW - Eye KW - feedback mechanism KW - lens KW - pannexins KW - purinergic receptor signaling KW - Retina ER - TY - JOUR TI - KCa3.1 ion channel: A novel therapeutic target for corneal fibrosis AU - Anumanthan, Govindaraj AU - Gupta, Suneel AU - Fink, Michael K. AU - Hesemann, Nathan P. AU - Bowles, Douglas K. AU - McDaniel, Lindsey M. AU - Muhammad, Maaz AU - Mohan, Rajiv R. T2 - PloS One AB - Vision impairment from corneal fibrosis is a common consequence of irregular corneal wound healing after injury. Intermediate-conductance calmodulin/calcium-activated K+ channels 3.1 (KCa3.1) play an important role in cell cycle progression and cellular proliferation. Proliferation and differentiation of corneal fibroblasts to myofibroblasts can lead to corneal fibrosis after injury. KCa3.1 has been shown in many non-ocular tissues to promote fibrosis, but its role in corneal fibrosis is still unknown. In this study, we characterized the expression KCa3.1 in the human cornea and its role in corneal wound healing in vivo using a KCa3.1 knockout (KCa3.1-/-) mouse model. Additionally, we tested the hypothesis that blockade of KCa3.1 by a selective KCa3.1 inhibitor, TRAM-34, could augment a novel interventional approach for controlling corneal fibrosis in our established in vitro model of corneal fibrosis. The expression of KCa3.1 gene and protein was analyzed in human and murine corneas. Primary human corneal fibroblast (HCF) cultures were used to examine the potential of TRAM-34 in treating corneal fibrosis by measuring levels of pro-fibrotic genes, proteins, and cellular migration using real-time quantitative qPCR, Western blotting, and scratch assay, respectively. Cytotoxicity of TRAM-34 was tested with trypan blue assay, and pro-fibrotic marker expression was tested in KCa3.1-/-. Expression of KCa3.1 mRNA and protein was detected in all three layers of the human cornea. The KCa3.1-/- mice demonstrated significantly reduced corneal fibrosis and expression of pro-fibrotic marker genes such as collagen I and α-smooth muscle actin (α-SMA), suggesting that KCa3.1 plays an important role corneal wound healing in vivo. Pharmacological treatment with TRAM-34 significantly attenuated corneal fibrosis in vitro, as demonstrated in HCFs by the inhibition TGFβ-mediated transcription of pro-fibrotic collagen I mRNA and α-SMA mRNA and protein expression (p<0.001). No evidence of cytotoxicity was observed. Our study suggests that KCa3.1 regulates corneal wound healing and that blockade of KCa3.1 by TRAM-34 offers a potential therapeutic strategy for developing therapies to cure corneal fibrosis in vivo. DA - 2018/// PY - 2018 DO - 10.1371/journal.pone.0192145 DP - PubMed VL - 13 IS - 3 SP - e0192145 J2 - PLoS ONE LA - eng SN - 1932-6203 ST - KCa3.1 ion channel L2 - http://www.ncbi.nlm.nih.gov/pubmed/29554088 ER - TY - JOUR TI - Lactate-H+ Transport Is a Significant Component of the In Vivo Corneal Endothelial Pump AU - Nguyen, Tracy T. AU - Bonanno, Joseph A. T2 - Investigative Ophthalmology & Visual Science DA - 2012/04/01/ PY - 2012 DO - 10.1167/iovs.12-9475 DP - iovs.arvojournals.org VL - 53 IS - 4 SP - 2020 EP - 2029 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?articleid=2188361 Y2 - 2018/05/29/02:25:41 L1 - http://iovs.arvojournals.org/data/journals/iovs/933465/i1552-5783-53-4-2020.pdf L2 - http://iovs.arvojournals.org/article.aspx?articleid=2188361 ER - TY - JOUR TI - Lactate-H+ Transport Is a Significant Component of the In Vivo Corneal Endothelial Pump AU - Nguyen, Tracy T. AU - Bonanno, Joseph A. T2 - Investigative Ophthalmology & Visual Science AB - Bicarbonate buffering can facilitate lactate efflux across the corneal endothelium from stroma to anterior chamber. Experiments in vivo suggest that this process significantly contributes to the endothelial pump. DA - 2012/04// PY - 2012 DO - 10.1167/iovs.12-9475 DP - PubMed Central VL - 53 IS - 4 SP - 2020 EP - 2029 J2 - Invest Ophthalmol Vis Sci SN - 0146-0404 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3995573/ Y2 - 2018/05/29/02:25:13 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3995573/pdf/i1552-5783-53-4-2020.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3995573/ ER - TY - JOUR TI - Transient outwardly rectifying potassium channel in the rabbit corneal endothelium AU - Watsky, M. A. AU - Cooper, K. AU - Rae, J. L. T2 - The Journal of Membrane Biology AB - Ionic currents from freshly dissociated rabbit corneal endothelial cells were examined using patch-clamp technology and a perforated patch technique. Whole-cell current recordings revealed a transient outward K(+)-selective current that was blockable in a dose-dependent manner by 4-aminopyridine (4-AP) and quinidine. This current is similar to the 'A'-type current present in many excitable cells and is the first reported instance of such a current in any epithelial cell type. In addition to the transient current, an outwardly rectifying nonselective cation current was also observed. This current is also blocked by quinidine. To examine the possible role of these currents in the stromal volume regulatory function of the endothelium, corneas were perfused under a specular microscope with a glutathione-bicarbonate Ringer's solution (GBR) or GBR plus either 1 mM quinidine or 10 mM 4-AP. For quinidine perfusions, control corneas swelled at a rate of 6 microns/hr, while quinidine-perfused corneas swelled at a rate of 48 microns/hr. For 4-AP perfusions, control corneas swelled at a rate of -2 microns/hr, while 4-AP perfused corneas swelled at a rate of 24 microns/hr. One possible mechanism of the stromal swelling induced by these K+ channel blockers may be the result of loss of the K+ recycling pathway necessary for proper Na+/K+ ATPase function. DA - 1992/06// PY - 1992 DP - PubMed VL - 128 IS - 2 SP - 123 EP - 132 J2 - J. Membr. Biol. LA - eng SN - 0022-2631 L2 - http://www.ncbi.nlm.nih.gov/pubmed/1501240 KW - Animals KW - Endothelium, Corneal KW - Kinetics KW - Membrane Potentials KW - Perfusion KW - Potassium Channels KW - Rabbits ER - TY - JOUR TI - Expression of the Inwardly Rectifying K+ Channel Kir2.1 in Native Bovine Corneal Endothelial Cells AU - Yang, Dongli AU - MacCallum, Donald K. AU - Ernst, Stephen A. AU - Hughes, Bret A. T2 - Investigative Ophthalmology & Visual Science DA - 2003/08/01/ PY - 2003 DO - 10.1167/iovs.02-1306 DP - iovs.arvojournals.org VL - 44 IS - 8 SP - 3511 EP - 3519 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?articleid=2200243 Y2 - 2018/05/28/15:10:58 L1 - http://iovs.arvojournals.org/data/journals/iovs/933711/7g0803003511.pdf L2 - http://iovs.arvojournals.org/article.aspx?articleid=2200243 ER - TY - BOOK TI - Ion Channels: From Structure to Function AU - Kew, James N. C. AU - Davies, Ceri H. AB - Ion channels are intimately involved in the everyday physiological functions that enable us to live a full and varied life. When disease strikes, malfunction of ion channels or their dependent is often involved, either as the cause or the effect of the illness. Thus, billions of dollars have been, and still are being, invested in research to understand the physiological and pathophysiological functions of ion channels in an attempt to develop novel therapeutic treatments for a wide range of diseases.This book provides a comprehensive overview of ion channel structure and function. It comprises two major parts. Part one is an introductory overview of the ion channel superfamily and the generic aspects of ion channel function. This part also reviews the methodologies by which ion channel function can be studied from the perspective of performing detailed biophysical characterization through to the deployment of high throughput approaches for identifying novel ion channel ligands.Part two of the book provides an in-depth review of the individual ion channel subfamilies and, as such, is subdivided into four broad sections: Voltage-Gated Ion Channels, Extracellular Ligand-Gated Ion Channels, Intracellular Ligand-Gated Ion Channels, and Polymodal-Gated Ion Channels, with each chapter focused on specific family members. These chapters have been written by world leading experts and provide a detailed overview of the structure, biophysics, localization, pharmacology, physiology, and disease relevance of each particular ion channel subfamily.Reviewing both the basic principles of ion channel function and providing a detailed up-to-date review of the phsyiological and pharmacological aspects of individual ion channel sub-families, this book constitutes both an excellent introduction to the field for non-specialists, as well as a highly valuable reference text for experienced researchers already working in the ion channel area. DA - 2010/// PY - 2010 DP - Google Books SP - 586 LA - en PB - Oxford University Press SN - 978-0-19-929675-0 ST - Ion Channels L2 - https://books.google.com.co/books?id=imGflU4p8zEC KW - Medical / Neuroscience KW - Science / Life Sciences / Cell Biology ER - TY - ELEC TI - Fluid transport by the cornea endothelium is dependent on buffering lactic acid efflux | American Journal of Physiology-Cell Physiology UR - https://www.physiology.org/doi/abs/10.1152/ajpcell.00095.2016?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed Y2 - 2018/05/28/03:18:04 L2 - https://www.physiology.org/doi/abs/10.1152/ajpcell.00095.2016?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed ER - TY - ELEC TI - Lactate-H+ Transport Is a Significant Component of the In Vivo Corneal Endothelial Pump UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3995573/ Y2 - 2018/05/28/02:21:01 L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3995573/ ER - TY - JOUR TI - Cardiac voltage-gated ion channels in safety pharmacology: Review of the landscape leading to the CiPA initiative AU - Huang, Hai AU - Pugsley, Michael K. AU - Fermini, Bernard AU - Curtis, Michael J. AU - Koerner, John AU - Accardi, Michael AU - Authier, Simon T2 - Journal of Pharmacological and Toxicological Methods T3 - Focused Issue on Safety Pharmacology AB - Voltage gated ion channels are central in defining the fundamental properties of the ventricular cardiac action potential (AP), and are also involved in the development of drug-induced arrhythmias. Many drugs can inhibit cardiac ion currents, including the Na+ current (INa), L-type Ca2+ current (Ica-L), and K+ currents (Ito, IK1, IKs, and IKr), and thereby affect AP properties in a manner that can trigger or sustain cardiac arrhythmias. Since publication of ICH E14 and S7B over a decade ago, there has been a focus on drug effects on QT prolongation clinically, and on the rapidly activating delayed rectifier current (IKr), nonclinically, for evaluation of proarrhythmic risk. This focus on QT interval prolongation and a single ionic current likely impacted negatively some drugs that lack proarrhythmic liability in humans. To rectify this issue, the Comprehensive in vitro proarrhythmia assay (CiPA) initiative has been proposed to integrate drug effects on multiple cardiac ionic currents with in silico modelling of human ventricular action potentials, and in vitro data obtained from human stem cell-derived ventricular cardiomyocytes to estimate proarrhythmic risk of new drugs with improved accuracy. In this review, we present the physiological functions and the molecular basis of major cardiac ion channels that contribute to the ventricle AP, and discuss the CiPA paradigm in drug development. DA - 2017/09/01/ PY - 2017 DO - 10.1016/j.vascn.2017.04.002 DP - ScienceDirect VL - 87 SP - 11 EP - 23 J2 - Journal of Pharmacological and Toxicological Methods SN - 1056-8719 ST - Cardiac voltage-gated ion channels in safety pharmacology UR - http://www.sciencedirect.com/science/article/pii/S1056871917300825 Y2 - 2018/05/27/16:08:52 L1 - https://ac.els-cdn.com/S1056871917300825/1-s2.0-S1056871917300825-main.pdf?_tid=01c7a21e-0379-42cc-ae95-6f7cbfc04d5c&acdnat=1527437511_35a2f820d6291879eb804777affa8031 L2 - https://www.sciencedirect.com/science/article/pii/S1056871917300825 KW - Action potential (AP) KW - Action potential duration (APD) KW - Cardiac action potential KW - Cardiac arrhythmias KW - Cardiac voltage-gated ion channels KW - Comprehensive in-vitro proarrhythmia assay (CiPA) KW - Delayed afterdepolarization (DAD) KW - Early afterdepolarization (EAD) KW - hERG KW - I KW - In-vitro study KW - Patch clamp KW - QT prolongation KW - Torsade de pointes (TdP) ER - TY - JOUR TI - Voltage-gated potassium channels as therapeutic targets AU - Wulff, Heike AU - Castle, Neil A. AU - Pardo, Luis A. T2 - Nature Reviews. Drug Discovery AB - The human genome encodes 40 voltage-gated K(+) channels (K(V)), which are involved in diverse physiological processes ranging from repolarization of neuronal and cardiac action potentials, to regulating Ca(2+) signalling and cell volume, to driving cellular proliferation and migration. K(V) channels offer tremendous opportunities for the development of new drugs to treat cancer, autoimmune diseases and metabolic, neurological and cardiovascular disorders. This Review discusses pharmacological strategies for targeting K(V) channels with venom peptides, antibodies and small molecules, and highlights recent progress in the preclinical and clinical development of drugs targeting the K(V)1 subfamily, the K(V)7 subfamily (also known as KCNQ), K(V)10.1 (also known as EAG1 and KCNH1) and K(V)11.1 (also known as HERG and KCNH2) channels. DA - 2009/12// PY - 2009 DO - 10.1038/nrd2983 DP - PubMed VL - 8 IS - 12 SP - 982 EP - 1001 J2 - Nat Rev Drug Discov LA - eng SN - 1474-1784 L2 - http://www.ncbi.nlm.nih.gov/pubmed/19949402 KW - Animals KW - Antibodies KW - Clinical Trials as Topic KW - Drug Delivery Systems KW - Drug Design KW - Drug Evaluation, Preclinical KW - Humans KW - Peptides KW - Potassium Channels, Voltage-Gated KW - Signal Transduction KW - Venoms ER - TY - JOUR TI - Kv3.3 potassium channels in lens epithelium and corneal endothelium AU - Rae, J. L. AU - Shepard, A. R. T2 - Experimental Eye Research AB - Human Kv3.3/KCNC3 is a Shaw-type potassium channel that has been mapped to chromosome 19q13.3-13.4. Complete mouse and rat Kv3.3 cDNA coding sequences have been published, yet the human Kv3.3 cDNA has remained incomplete for years. We report here for the first time the amino acid sequence for hKv3.3 and the electrophysiological behavior of the encoded channel in transiently transfected mammalian cells. In addition, we report the occurrence of Kv3.3 message in rabbit corneal endothelial cells and the properties of the currents when the corneal channel is expressed. The hKv3.3 gene is highly GC-rich (69%) and contains numerous GC runs which made DNA sequencing and PCR amplification especially problematic. The full-length sequence contains two possible start codons. The encoded 757 amino acid hKv3. 3 protein is about 93% identical to mouse and rat Kv3.3 in the first 659 amino acids before the C-terminal domains diverge greatly as a result of alternative splicing. The rabbit cornea Kv3.3 is a close sequence match for hKv3.3 even in the C-terminal domain. However, we have not yet found a cornea sequence which contains the first potential start codon from hKv3.3. Electrophysiologically, the hKv3. 3 channel produces an A-current although expression of constructs which lack the 5' region of the first start codon inactivate much more slowly than full-length constructs. This short hKv3.3 construct also shows changes in activation. DA - 2000/03// PY - 2000 DO - 10.1006/exer.1999.0796 DP - PubMed VL - 70 IS - 3 SP - 339 EP - 348 J2 - Exp. Eye Res. LA - eng SN - 0014-4835 L2 - http://www.ncbi.nlm.nih.gov/pubmed/10712820 KW - Amino Acid Sequence KW - Animals KW - DNA, Complementary KW - Electrophysiology KW - Endothelium, Corneal KW - Epithelium KW - Humans KW - Lens, Crystalline KW - Mice KW - Molecular Sequence Data KW - Patch-Clamp Techniques KW - Potassium Channels KW - Potassium Channels, Voltage-Gated KW - Rabbits KW - Rats KW - Shaw Potassium Channels ER - TY - CHAP TI - Voltage Gated Potassium Channels: Structure and Function of Kv1 to Kv9 Subfamilies AU - Rudy, B. AU - Maffie, J. AU - Amarillo, Y. AU - Clark, B. AU - Goldberg, E. M. AU - Jeong, H. -Y. AU - Kruglikov, I. AU - Kwon, E. AU - Nadal, M. AU - Zagha, E. T2 - Encyclopedia of Neuroscience A2 - Squire, Larry R. AB - The nervous system contains a large diversity of potassium channels, the membrane proteins that regulate the movement of potassium ions across the cell membrane. All potassium channels have a similar ionic selectivity for potassium ions but vary in how, when, and for how long their pore is open. K+ channel diversity is one of the main factors contributing to the dynamic, electrophysiological identity of neurons and to the functional specificity of the modulatory actions of neurotransmitters and neuropeptides. This article reviews the K+ channels for which the opening of the pore is controlled by the electrical membrane potential and discusses what has been learned about the contribution of each channel type to neuronal function. CY - Oxford DA - 2009/// PY - 2009 DP - ScienceDirect SP - 397 EP - 425 PB - Academic Press SN - 978-0-08-045046-9 ST - Voltage Gated Potassium Channels UR - https://www.sciencedirect.com/science/article/pii/B9780080450469016302 Y2 - 2018/05/27/04:00:30 L2 - https://www.sciencedirect.com/science/article/pii/B9780080450469016302 KW - A-type K+ channelsC-type inactivationDelayed rectifiersDendrotoxinGating currentsK+ channelsM-type K+ currentsN-type inactivationSpike repolarizationVoltage-dependent gatingVoltage-gated K+ channelsVoltage sensor ER - TY - ELEC TI - Voltage-gated potassium channels | Introduction | BPS/IUPHAR Guide to PHARMACOLOGY UR - http://www.guidetopharmacology.org/GRAC/FamilyIntroductionForward?familyId=81 Y2 - 2018/05/25/13:47:52 L2 - http://www.guidetopharmacology.org/GRAC/FamilyIntroductionForward?familyId=81 ER - TY - JOUR TI - Mechanisms of Activation of Voltage-Gated Potassium Channels AU - Grizel, A. V. AU - Glukhov, G. S. AU - Sokolova, O. S. T2 - Acta Naturae AB - Voltage-gated potassium ion channels (Kv) play an important role in a variety of cellular processes, including the functioning of excitable cells, regulation of apoptosis, cell growth and differentiation, the release of neurotransmitters and hormones, maintenance of cardiac activity, etc. Failure in the functioning of Kv channels leads to severe genetic disorders and the development of tumors, including malignant ones. Understanding the mechanisms underlying Kv channels functioning is a key factor in determining the cause of the diseases associated with mutations in the channels, and in the search for new drugs. The mechanism of activation of the channels is a topic of ongoing debate, and a consensus on the issue has not yet been reached. This review discusses the key stages in studying the mechanisms of functioning of Kv channels and describes the basic models of their activation known to date. DA - 2014/// PY - 2014 DP - PubMed Central VL - 6 IS - 4 SP - 10 EP - 26 J2 - Acta Naturae SN - 2075-8251 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4273088/ Y2 - 2018/05/24/19:53:18 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4273088/pdf/AN20758251-23-010.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4273088/ ER - TY - JOUR TI - Decreasing expression of the G1-phase inhibitors, p21Cip1 and p16INK4a, promotes division of corneal endothelial cells from older donors AU - Joyce, Nancy C. AU - Harris, Deshea L. T2 - Molecular Vision AB - PURPOSE: The current studies were conducted to determine whether the cyclin-dependent kinase inhibitors, p21Cip1 (p21 cyclin-dependent kinase-interacting protein 1) and p16INK4a (p16 cyclin-dependent kinase inhibitor 1A), help mediate G(1)-phase inhibition in human corneal endothelial cells (HCEC) by testing the effect of siRNA (small interfering RNA)-mediated down-regulation of the expression of these inhibitors on cell cycle entry and proliferation in HCEC cultured from older donors. METHODS: HCEC were obtained from National Disease Research Interchange, Philadelphia, PA, and cultured according to published methods. Cells were electroporated in the presence of either a non-silencing siRNA control or p21+p16 siRNA. The efficiency of siRNA transfer was observed by fluorescence microscopy of Cy3-labeled control siRNA. Viability was determined by direct counting of cells before and after electroporation. The ability of p21+p16 siRNA to decrease the protein expression of p21Cip1 and p16INK4a was determined by semi-quantitative analysis of western blots. The effect of siRNA treatment on cell cycle progression and proliferation was determined 1, 5, and 11 days after electroporation by counting Ki67-positive cells and total DAPI-stained nuclei. RESULTS: siRNA was efficiently transferred to HCEC by the electroporation method. The average cell loss was 41.25% at 24 h following electroporation. Protein levels of both p21Cip1 and p16INK4a were significantly decreased as the result of p21+p16 siRNA treatment. This treatment significantly increased the average number of Ki67-positive cells over controls and increased the total number of cells in a time-dependent manner. CONCLUSIONS: Both p21Cip1 and p16INK4a are involved in negative regulation of the cell cycle in HCEC and, thereby, provide an effective barrier to cell division. The siRNA-induced reduction in expression of these proteins increased the number of cells entering the cell cycle, as well as total cell numbers. Thus, reduction of the levels of p21Cip1 and p16INK4a could be useful in the development of treatments to induce transient cell division to increase corneal endothelial cell density. DA - 2010/05/25/ PY - 2010 DP - PubMed VL - 16 SP - 897 EP - 906 J2 - Mol. Vis. LA - eng SN - 1090-0535 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20508865 KW - Adult KW - Aged KW - Aging KW - Cell Cycle KW - Cell Division KW - Cell Survival KW - Cells, Cultured KW - Cyclin-Dependent Kinase Inhibitor p16 KW - Cyclin-Dependent Kinase Inhibitor p21 KW - Down-Regulation KW - Electroporation KW - Endothelial Cells KW - Endothelium, Corneal KW - G1 Phase KW - Humans KW - Middle Aged KW - RNA, Small Interfering ER - TY - JOUR TI - Ionic channels in corneal endothelium AU - Rae, J. L. AU - Watsky, M. A. T2 - The American Journal of Physiology AB - Single-channel patch-clamp techniques as well as standard and perforated-patch whole cell voltage-clamp techniques have been applied to the study of ionic channels in the corneal endothelium of several species. These studies have revealed two major K+ currents. One is due to an anion- and temperature-stimulated channel that is blocked by Cs+ but not by most other K+ channel blockers, and the other is similar to the family of A-currents found in excitable cells. The A-current is transient after a depolarizing voltage step and is blocked by both 4-aminopyridine and quinidine. These two currents are probably responsible for setting the -50 to -60 mV resting voltage reported for these cells. A Ca(2+)-activated ATP-inhibited nonselective cation channel and a tetrodotoxin-blocked Na+ channel are possible Na+ inflow pathways, but, given their gating properties, it is not certain that either channel works under physiological conditions. A large-conductance anion channel has also been identified by single-channel patch-clamp techniques. Single corneal endothelial cells have input resistances of 5-10 G omega and have steady-state K+ currents that are approximately 10 pA at the resting voltage. Pairs or monolayers of cells are electrically coupled and dye coupled through gap junctions. DA - 1996/04// PY - 1996 DO - 10.1152/ajpcell.1996.270.4.C975 DP - PubMed VL - 270 IS - 4 Pt 1 SP - C975 EP - 989 J2 - Am. J. Physiol. LA - eng SN - 0002-9513 L2 - http://www.ncbi.nlm.nih.gov/pubmed/8928754 KW - Animals KW - Chloride Channels KW - Electrophysiology KW - Endothelium, Corneal KW - Gap Junctions KW - Humans KW - Ion Channels KW - Potassium Channels KW - Sodium Channels ER - TY - JOUR TI - Overview of the voltage-gated sodium channel family AU - Yu, Frank H AU - Catterall, William A T2 - Genome Biology AB - Different sodium channels have remarkably similar functional properties, but small changes in sodium-channel function are biologically relevant, as underscored by mutations that cause several human diseases of hyperexcitability., Selective permeation of sodium ions through voltage-dependent sodium channels is fundamental to the generation of action potentials in excitable cells such as neurons. These channels are large integral membrane proteins and are encoded by at least ten genes in mammals. The different sodium channels have remarkably similar functional properties, but small changes in sodium-channel function are biologically relevant, as underscored by mutations that cause several human diseases of hyperexcitability. DA - 2003/// PY - 2003 DP - PubMed Central VL - 4 IS - 3 SP - 207 J2 - Genome Biol SN - 1465-6906 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC153452/ Y2 - 2018/05/21/13:23:31 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC153452/pdf/gb-2003-4-3-207.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC153452/ ER - TY - JOUR TI - Modeling corneal metabolism and oxygen transport during contact lens wear AU - Chhabra, Mahendra AU - Prausnitz, John M. AU - Radke, Clayton J. T2 - Optometry and Vision Science: Official Publication of the American Academy of Optometry AB - PURPOSE: A metabolic model is developed for cornea-contact-lens system to elucidate the role of glucose metabolism in oxygenation of the cornea and to gauge the role that contact lens oxygen transmissibility plays in avoiding hypoxia-induced corneal abnormalities for extended wear applications. METHODS: Oxygen transport through the cornea and contact lens system is typically described by oxygen diffusion with reactive loss. Oxygen in the cornea, however, interacts with other metabolic species, specifically glucose, lactate ion, bicarbonate ion, hydrogen ion, and carbon dioxide via aerobic glycolysis (Krebs or tricarboxylic acid cycle) and anaerobic glycolysis. Here, corneal aerobic and anaerobic metabolic reactions are incorporated into a six-layer (endothelium, stroma, epithelium, postlens tear film, contact lens, and prelens tear film) steady-state continuum reaction-diffusion model to quantify oxygen transport. We also define a new index, the oxygen deficiency factor (ODF), for gauging corneal oxygenation. As opposed to other current gauges of hypoxia, ODF is a local and sensitive measure of both the extent and severity of corneal oxygen deprivation. RESULTS: We calculate not only oxygenation of the cornea but also its coupled glucose, lactate, and acidosis behavior. For the first time, the metabolic shift from aerobic to anaerobic glycolysis is explicitly incorporated into the transport and consumption of oxygen in the cornea on closed-eye contact lens wear. Adoption of enzymatic Monod kinetics for the metabolic reactions permits realistic assessment of local species concentrations throughout the cornea. We find that anerobic-produced lactate transports out of the cornea into the anterior chamber, whereas buffering bicarbonate ion transports into the comea from the anterior chamber. CONCLUSIONS: The coupling of oxygen with other reactive species in corneal metabolism provides useful insight into the transport of oxygen in cornea-contact-lens system. Specifically, we find that in addition to oxygen depletion and acidosis in the cornea, lactate concentration increases while glucose and bicarbonate concentrations decrease from the endothelium toward the epithelium. Unlike other indices of corneal oxygenation, ODF is sensitive specifically to regions of cornea with local oxygen deficiency. Accordingly, ODF is a useful physiologic index to assess the extent and severity of hypoxia in the cornea. DA - 2009/05// PY - 2009 DO - 10.1097/OPX.0b013e31819f9e70 DP - PubMed VL - 86 IS - 5 SP - 454 EP - 466 J2 - Optom Vis Sci LA - eng SN - 1538-9235 L2 - http://www.ncbi.nlm.nih.gov/pubmed/19357551 KW - Aerobiosis KW - Anaerobiosis KW - Animals KW - Contact Lenses KW - Cornea KW - Diffusion KW - Glucose KW - Glycolysis KW - Humans KW - Hypoxia KW - Oxygen KW - Oxygen Consumption KW - Rabbits KW - Reference Values ER - TY - JOUR TI - Soluble adenylyl cyclase mediates bicarbonate-dependent corneal endothelial cell protection AU - Li, Shimin AU - Allen, Kah Tan AU - Bonanno, Joseph A. T2 - American Journal of Physiology. Cell Physiology AB - Cyclic AMP produced from membrane receptor complex bound adenylyl cyclases is protective in corneal endothelial cells (CEC). CEC also express soluble adenylyl cyclase (sAC), which is localized throughout the cytoplasm. When activated by HCO(3)(-), cAMP concentration ([cAMP]) increases by ∼50%. Here we ask if cAMP produced from sAC is also protective. We examined the effects of HCO(3)(-), pH, phosphodiesterase 4 inhibition by rolipram, sAC inhibition by 2HE (2-hydroxyestradiol), and sAC small interfering RNA (siRNA) knockdown on basal and staurosporine-mediated apoptosis. HCO(3)(-) (40 mM) or 50 μM rolipram raised [cAMP] to similar levels and protected endothelial cells by 50% relative to a HCO(3)(-)-free control, whereas 2HE, which decreased [cAMP] by 40%, and H89 (PKA inhibitor) doubled the apoptotic rate. sAC expression was reduced by two-thirds in the absence of HCO(3)(-) and was reduced to 15% of control by sAC siRNA. Protection by HCO(3)(-) was eliminated in siRNA-treated cells. Similarly, caspase-3 activity and cytochrome c release were reduced by HCO(3)(-) and enhanced by 2HE or siRNA. Analysis of percent annexin V+ cells as a function of [cAMP] revealed an inverse, nonlinear relation, suggesting a protective threshold [cAMP] of 10 pmol/mg protein. Relative levels of phosphorylated cAMP response element binding protein and phosphorylated Bcl-2 were decreased in CEC treated with 2HE or siRNA, suggesting that HCO(3)(-)-dependent endogenous sAC activity can mobilize antiapoptotic signal transduction. Overall, our data suggest a new role for sAC in endogenous cellular protection. DA - 2011/02// PY - 2011 DO - 10.1152/ajpcell.00314.2010 DP - PubMed VL - 300 IS - 2 SP - C368 EP - 374 J2 - Am. J. Physiol., Cell Physiol. LA - eng SN - 1522-1563 L2 - http://www.ncbi.nlm.nih.gov/pubmed/21123735 KW - Adenylyl Cyclase Inhibitors KW - Adenylyl Cyclases KW - Animals KW - Annexin A5 KW - Apoptosis KW - Bicarbonates KW - Caspase 3 KW - Cattle KW - Cells, Cultured KW - Cyclic AMP KW - Cyclic AMP Response Element-Binding Protein KW - Cytochromes c KW - Epithelium, Corneal KW - Estradiol KW - Isoquinolines KW - Phosphodiesterase 4 Inhibitors KW - Phosphorylation KW - Protein Kinase Inhibitors KW - Proto-Oncogene Proteins c-bcl-2 KW - RNA, Small Interfering KW - Rolipram KW - Staurosporine KW - Sulfonamides ER - TY - JOUR TI - HCO(3)(-)-dependent soluble adenylyl cyclase activates cystic fibrosis transmembrane conductance regulator in corneal endothelium AU - Sun, Xing Cai AU - Zhai, Chang-Bin AU - Cui, Miao AU - Chen, Yanqiu AU - Levin, Lonny R. AU - Buck, Jochen AU - Bonanno, Joseph A. T2 - American Journal of Physiology. Cell Physiology AB - cAMP-dependent activation of the cystic fibrosis transmembrane conductance regulator (CFTR) regulates fluid transport in many tissues. Secretion by the corneal endothelium is stimulated by cAMP and dependent on HCO(3)(-). We asked whether HCO(3)(-) can secondarily increase CFTR permeability in bovine corneal endothelial cells (BCEC) by activating soluble adenylyl cyclase (sAC). Immunofluorescence suggests that sAC is distributed throughout the cytoplasm. HCO(3)(-) (40 mM) increased cAMP concentration 42% in the presence of 50 microM rolipram (a phosphodiesterase 4 inhibitor), and a standard HCO(3)(-) Ringer solution (28.5 mM) increased apical Cl(-) permeability by 78% relative to HCO(3)(-)-free solution. The HCO(3)(-)-dependent increase in Cl(-) permeability was reduced 60% by 20 mM NaHSO(3) (a weak agonist of sAC). NaHSO(3) alone increased apical Cl(-) permeability by only 13%. The HCO(3)(-)-dependent increase in Cl(-) permeability was reduced 57% in the presence of 50 microM Rp-adenosine 3',5'-cyclic monophosphorothioate, and 86% by 50 microM 5-nitro-2-(3-phenylpropyl-amino)benzoic acid but unaffected by 200 microM apical H(2)DIDS. CFTR phosphorylation was increased 23, 150, and 32% by 20 mM HSO(3)(-), 28.5 mM HCO(3)(-), and 28.5 mM HCO(3)(-) + 20 mM HSO(3)(-), respectively. Activation of apical Cl(-) permeability by 5 microM genistein was increased synergistically by HCO(3)(-) over that due to genistein and HCO(3)(-) alone. We conclude that HCO(3)(-)-stimulated sAC is a form of autocrine signaling that contributes to baseline cAMP production, thereby affecting baseline CFTR activity in BCEC. This form of autocrine signaling may be important in tissues that express sAC and exhibit robust HCO(3)(-) influx (e.g., ocular ciliary epithelium, choroid plexus, and airway epithelium). DA - 2003/05// PY - 2003 DO - 10.1152/ajpcell.00400.2002 DP - PubMed VL - 284 IS - 5 SP - C1114 EP - 1122 J2 - Am. J. Physiol., Cell Physiol. LA - eng SN - 0363-6143 L2 - http://www.ncbi.nlm.nih.gov/pubmed/12519749 KW - Adenylyl Cyclases KW - Animals KW - Bicarbonates KW - Cattle KW - Cell Membrane KW - Cells, Cultured KW - Chlorides KW - Colforsin KW - Cyclic AMP KW - Cystic Fibrosis Transmembrane Conductance Regulator KW - Endothelium, Corneal KW - Permeability KW - Phosphorylation KW - Solubility KW - Sulfites ER - TY - JOUR TI - Expression and distribution of the serum and glucocorticoid regulated kinase and the epithelial sodium channel subunits in the human cornea AU - Rauz, Saaeha AU - Walker, Elizabeth A. AU - Murray, Philip I. AU - Stewart, Paul M. T2 - Experimental Eye Research AB - The sodium transporting capacity of the corneal endothelium is vital for preserving corneal transparency, and has traditionally been attributed to the endothelial pump transporting sodium and bicarbonate across the corneal endothelium, maintaining the cornea in a dehydrated state. Recent studies have shown that the enzyme, serum and glucocorticoid regulated kinase isoform 1 (SGK1), plays a pivotal role in the corticosteroid induction of epithelial sodium transport in tissues such as the distal nephron, through activation of the epithelial sodium channels (ENaC). This study was designed to identify whether these elements were present within the human cornea. In situ hybridisation studies were conducted on paraffin embedded sections from six human eyes, using in-house generated cRNA antisense probes for human SGK1 and ENaC subunits (alpha, beta, gamma), and confirmed expression of SGK1 and all ENaC subunits in the corneal endothelial cytoplasm. Although ENaC subunits were not demonstrated in the corneal epithelium, SGK1 mRNA was identified in the nuclear region of central basal cells of the corneal epithelium, and limbal epithelial cells. Minimal chromagen precipitation was seen in the Bowman's membrane, corneal stroma, or Descemet's membrane. Control experiments consisted of no antisense probe, competition of the labelled antisense cRNA probe by a 60-fold excess unlabelled antisense cRNA, and use of labelled sense cRNA probes, revealing minimal or no hybridisation signal throughout the corneal layers. These data define components of the mineralocorticoid regulatory pathways of sodium transport in human corneal endothelium, and provide evidence for an additional mechanism contributing to corneal transparency and the 'metabolic' sodium pump. DA - 2003/07// PY - 2003 DP - PubMed VL - 77 IS - 1 SP - 101 EP - 108 J2 - Exp. Eye Res. LA - eng SN - 0014-4835 L2 - http://www.ncbi.nlm.nih.gov/pubmed/12823993 KW - Cornea KW - Cytoplasm KW - Endothelium, Corneal KW - Epithelial Cells KW - Epithelial Sodium Channels KW - Epithelium, Corneal KW - Humans KW - Immediate-Early Proteins KW - In Situ Hybridization KW - Nuclear Proteins KW - Protein Isoforms KW - Protein-Serine-Threonine Kinases KW - Sodium Channels ER - TY - JOUR TI - Evidence for a central role for electro-osmosis in fluid transport by corneal endothelium AU - Sánchez, J. M. AU - Li, Y. AU - Rubashkin, A. AU - Iserovich, P. AU - Wen, Q. AU - Ruberti, J. W. AU - Smith, R. W. AU - Rittenband, D. AU - Kuang, K. AU - Diecke, F. P. J. AU - Fischbarg, J. T2 - The Journal of Membrane Biology AB - The mechanism of transepithelial fluid transport remains unclear. The prevailing explanation is that transport of electrolytes across cell membranes results in local concentration gradients and transcellular osmosis. However, when transporting fluid, the corneal endothelium spontaneously generates a locally circulating current of approximately 25 microA cm(-2), and we report here that electrical currents (0 to +/-15 microA cm(-2)) imposed across this layer induce fluid movements linear with the currents. As the imposed currents must be approximately 98% paracellular, the direction of induced fluid movements and the rapidity with which they follow current imposition (rise time < or =3 sec) is consistent with electro-osmosis driven by sodium movement across the paracellular pathway. The value of the coupling coefficient between current and fluid movements found here (2.37 +/- 0.11 microm cm(2) hr(-1) microA (-1), suggests that: 1) the local endothelial current accounts for spontaneous transendothelial fluid transport; 2) the fluid transported becomes isotonically equilibrated. Ca(++)-free solutions or endothelial damage eliminate the coupling, pointing to the cells and particularly their intercellular junctions as a main site of electro-osmosis. The polycation polylysine, which is expected to affect surface charges, reverses the direction of current-induced fluid movements. Fluid transport is proportional to the electrical resistance of the ambient medium. Taken together, the results suggest that electro-osmosis through the intercellular junctions is the primary process in a sequence of events that results in fluid transport across this preparation. DA - 2002/05/01/ PY - 2002 DO - 10.1007/s00232-001-0151-9 DP - PubMed VL - 187 IS - 1 SP - 37 EP - 50 J2 - J. Membr. Biol. LA - eng SN - 0022-2631 L2 - http://www.ncbi.nlm.nih.gov/pubmed/12029376 KW - Animals KW - Biological Transport, Active KW - Electrochemistry KW - Endothelium, Corneal KW - In Vitro Techniques KW - Intercellular Junctions KW - Membrane Potentials KW - Models, Biological KW - Models, Chemical KW - Osmolar Concentration KW - Osmosis KW - Osmotic Pressure KW - Permeability KW - Rabbits KW - Sensitivity and Specificity KW - Water KW - Water-Electrolyte Balance ER - TY - JOUR TI - Fluid Transport Across Leaky Epithelia: Central Role of the Tight Junction and Supporting Role of Aquaporins AU - Fischbarg, Jorge T2 - Physiological Reviews AB - The mechanism of epithelial fluid transport remains unsolved, which is partly due to inherent experimental difficulties. However, a preparation with which our laboratory works, the corneal endothelium, is a simple leaky secretory epithelium in which we have made some experimental and theoretical headway. As we have reported, transendothelial fluid movements can be generated by electrical currents as long as there is tight junction integrity. The direction of the fluid movement can be reversed by current reversal or by changing junctional electrical charges by polylysine. Residual endothelial fluid transport persists even when no anions (hence no salt) are being transported by the tissue and is only eliminated when all local recirculating electrical currents are. Aquaporin (AQP) 1 is the only AQP present in these cells, and its deletion in AQP1 null mice significantly affects cell osmotic permeability (by ∼40%) but fluid transport much less (∼20%), which militates against the presence of sizable water movements across the cell. In contrast, AQP1 null mice cells have reduced regulatory volume decrease (only 60% of control), which suggests a possible involvement of AQP1 in either the function or the expression of volume-sensitive membrane channels/transporters. A mathematical model of corneal endothelium we have developed correctly predicts experimental results only when paracellular electro-osmosis is assumed rather than transcellular local osmosis. Our evidence therefore suggests that the fluid is transported across this layer via the paracellular route by a mechanism that we attribute to electro-osmotic coupling at the junctions. From our findings we have developed a novel paradigm for this preparation that includes 1) paracellular fluid flow; 2) a crucial role for the junctions; 3) hypotonicity of the primary secretion; and 4) an AQP role in regulation rather than as a significant water pathway. These elements are remarkably similar to those proposed by the laboratory of Adrian Hill for fluid transport across other leaky epithelia. DA - 2010/10/01/ PY - 2010 DO - 10.1152/physrev.00025.2009 DP - physiology.org (Atypon) VL - 90 IS - 4 SP - 1271 EP - 1290 J2 - Physiological Reviews SN - 0031-9333 ST - Fluid Transport Across Leaky Epithelia UR - https://www.physiology.org/doi/abs/10.1152/physrev.00025.2009 Y2 - 2018/05/17/20:38:47 L1 - https://www.physiology.org/doi/pdf/10.1152/physrev.00025.2009?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed L2 - https://www.physiology.org/doi/abs/10.1152/physrev.00025.2009?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed ER - TY - JOUR TI - Fluid and ion transport in corneal endothelium: insensitivity to modulators of Na(+)-K(+)-2Cl- cotransport AU - Riley, M. V. AU - Winkler, B. S. AU - Starnes, C. A. AU - Peters, M. I. T2 - The American Journal of Physiology AB - The role of Na(+)-K(+)-2Cl- cotransport in ion and fluid transport of the corneal endothelium was examined by measuring changes in corneal hydration and uptake of 86Rb by the endothelial cell layer. Isolated, intact rabbit corneas maintain normal hydration when they are superfused at the endothelial surface with bicarbonate (HCO3-)-Ringer solutions as a result of equilibrium between active ion and fluid transport out of the stromal tissue and leak of fluid into stromal tissue from the aqueous humor. Furosemide and bumetanide did not alter this equilibrium when they were added to the superfusion medium. Uptake of 86Rb by the endothelium of the incubated cornea was increased 25% by bumetanide, but uptake in the presence of ouabain (70% less than that of controls) was not changed by bumetanide. In Na(+)-free medium, uptake of 86Rb was reduced by 58%, but it was unchanged in Cl(-)-free medium. Calyculin A, a protein phosphatase inhibitor and activator of Na(+)-K(+)-Cl- cotransport, was without effect on 86Rb uptake. Hypertonicity (345 mosmol/kg) increased uptake slightly, whereas hypotonicity (226 mosmol/kg) caused a 33% decrease. Neither of these changes was significantly different when bumetanide was present in the media. It is concluded that Na(+)-K(+)-2Cl- cotransporter activity is not exhibited by the in situ corneal endothelium and does not play a role in the ion and fluid transport of this cell layer. Its presence in cultured endothelial cells may reflect the reported importance of this protein in growth, proliferation, and differentiation. DA - 1997/11// PY - 1997 DP - PubMed VL - 273 IS - 5 Pt 1 SP - C1480 EP - 1486 J2 - Am. J. Physiol. LA - eng SN - 0002-9513 ST - Fluid and ion transport in corneal endothelium L2 - http://www.ncbi.nlm.nih.gov/pubmed/9374632 KW - Animals KW - Biological Transport KW - Bumetanide KW - Carrier Proteins KW - Cells, Cultured KW - Chlorides KW - Colforsin KW - Cornea KW - Endothelium, Corneal KW - Furosemide KW - In Vitro Techniques KW - Kinetics KW - Mannitol KW - Perfusion KW - Rabbits KW - Rubidium KW - Rubidium Radioisotopes KW - Sodium KW - Sodium-Potassium-Chloride Symporters KW - Stromal Cells KW - Urea ER - TY - JOUR TI - Regulation of Na-K-2Cl cotransport in cultured bovine corneal endothelial cells AU - Diecke, Friedrich P. AU - Wen, Quan AU - Iserovich, Pavel AU - Li, Jianfeng AU - Kuang, Kunyan AU - Fischbarg, Jorge T2 - Experimental Eye Research AB - We have previously demonstrated the presence of a Na(+)-K(+)-2Cl cotransporter in cultured bovine corneal endothelial cells (CBCEC) and determined that this cotransporter is located in the basolateral membrane. This transporter may contribute to volume regulation and transendothelial fluid transport. We have now investigated factors regulating the activity of the cotransporter. This activity was assessed by measuring the bumetanide-sensitive (86)Rubidium ((86)Rb) uptake in (86)Rb-containing solutions. Data were normalized to protein content determined with a Lowry protein assay. We investigated the regulation by extracellular and intracellular ion concentrations, by osmotic gradients, and by second messengers. Our results indicate that extracellular Na+ and K+ each are required for activation of the cotransporter and activate with first-order kinetics at half-maximally effective concentrations (k(1/2)) of 21.1 and 1.33 mM, respectively. Extracellular Cl- is also required for cotransport activation, but shows higher order kinetics; the k(1/2) for Cl- is 28.1 mM and the Hill coefficient 2.1. HCO(3)(-) exerts a modulating effect on cotransporter activity; at 0 HCO(3)(-) the bumetanide-sensitive K(+) uptake is reduced by 30% compared to that at 26 mm HCO(3)(-). Manipulations of the intracellular [Cl-] by preincubation in Cl- -free solution or inhibition of Cl- efflux resulted in increased uptake at low [Cl-](i) and decreased uptake at high [Cl-](i). To assess the role of protein kinases in the regulation of cotransport, we have determined the effect of protein kinase inhibitors. H-89 and KT5270, inhibitors of PKA, inhibit cotransport almost completely, while calphostin C, an inhibitor of PKC, produces a small activation of cotransport. The tyrosine kinase inhibitor genistein reduced K+ uptake while its inactive analog daidzein was without effect. The calmodulin kinase inhibitor KN-93 was without effect. We also investigated the effects of phosphatase inhibitors. Calyculin A (k(1/2)=21 nM) and okadaic acid (k(1/2)=915 nM) produced approximate doubling of K+ uptake, suggesting that phosphatase 1 is dominant. We also investigated the role of the cytoskeleton and its activation. Reduction of Ca(i)(2+) by preincubation in Ca2+ -free medium as well as by exposure to W-7, an inhibitor of the binding of Ca(2+) to calmodulin, reduced K+ uptake. Consistent with this, ML-7, a relatively specific inhibitor of the Ca2+ -calmodulin activated myosin light chain kinase, inhibited cotransport by 40%. The Ca2+ -calmodulin activated myosin light chain kinase contributes to the modulation of the cytoskeleton by regulating the actin-myosin interaction. Consistent with the above, disruption of the actin polymerization by cytochalasin D led to a decrease in K+ uptake. We conclude that extracellular Na+, K+ and Cl- are requirements for the function of the CBCEC Na(+)-K(+)-2Cl(-) cotransporter, while intracellular Cl- and extracellular HCO(3)(-) modulate its activity. Several protein kinases, including PKA, PKC, tyrosine kinase, and myosin light chain kinase, modulate the K+ uptake. Another modulating pathway for cotransport involves the state of the cytoskeleton. DA - 2005/06// PY - 2005 DO - 10.1016/j.exer.2004.12.008 DP - PubMed VL - 80 IS - 6 SP - 777 EP - 785 J2 - Exp. Eye Res. LA - eng SN - 0014-4835 L2 - http://www.ncbi.nlm.nih.gov/pubmed/15939033 KW - Animals KW - Cattle KW - Cells, Cultured KW - Cornea KW - Cytoskeletal Proteins KW - Dose-Response Relationship, Drug KW - Enzyme Inhibitors KW - Ions KW - Oxazoles KW - Phosphorylation KW - Sodium-Potassium-Chloride Symporters ER - TY - JOUR TI - Resting voltage measurements of the rabbit corneal endothelium using patch-current clamp techniques AU - Watsky, M. A. AU - Rae, J. L. T2 - Investigative Ophthalmology & Visual Science AB - The resting potential (Em) of freshly isolated rabbit corneal endothelium was measured at room temperature (22 degrees C) and at 34 degrees C. Due to the wide range of values reported in the literature and the difficulty in obtaining long-term measurements using microelectrodes in these cells, a current-clamp technique was employed using whole cell patch-clamp electrodes. The electrodes contained a K+ methanesulfonate-based intracellular solution, and a NaCl/HCO3- Ringer's solution was used extracellularly. Three preparations of endothelium were examined: single dissociated cells, the isolated monolayer (stripped from the stroma with Descemet's membrane), and the intact isolated cornea. The perforated-patch technique, with amphotericin B in the electrode, was also used with the intact-cornea preparation at 34 degrees C. The mean Em values for the combined preparations at 22 degrees C and 34 degrees C were -35.3 mV and -55.0 mV, respectively; those for the intact-cornea preparation were -34.4 mV and -61.6 mV (at 22 degrees C and 34 degrees C, respectively). The isolated monolayer preparation showed a small but significant depolarization at both temperatures. These results demonstrate temperature dependence for Em in the corneal endothelium and show that more extensively dissected preparations have similar although not identical Ems to those of the intact cornea. DA - 1991/01// PY - 1991 DP - PubMed VL - 32 IS - 1 SP - 106 EP - 111 J2 - Invest. Ophthalmol. Vis. Sci. LA - eng SN - 0146-0404 L2 - http://www.ncbi.nlm.nih.gov/pubmed/1987091 KW - Amphotericin B KW - Animals KW - Electrodes KW - Endothelium, Corneal KW - Membrane Potentials KW - Rabbits KW - Temperature ER - TY - JOUR TI - Human SLC4A11 Is a Novel NH3/H+ Co-transporter AU - Zhang, Wenlin AU - Ogando, Diego G. AU - Bonanno, Joseph A. AU - Obukhov, Alexander G. T2 - The Journal of Biological Chemistry AB - SLC4A11 has been proposed to be an electrogenic membrane transporter, permeable to Na(+), H(+) (OH(-)), bicarbonate, borate, and NH4 (+). Recent studies indicate, however, that neither bicarbonate or borate is a substrate. Here, we examined potential NH4 (+), Na(+), and H(+) contributions to electrogenic ion transport through SLC4A11 stably expressed in Na(+)/H(+) exchanger-deficient PS120 fibroblasts. Inward currents observed during exposure to NH4Cl were determined by the [NH3]o, not [NH4 (+)]o, and current amplitudes varied with the [H(+)] gradient. These currents were relatively unaffected by removal of Na(+), K(+), or Cl(-) from the bath but could be reduced by inclusion of NH4Cl in the pipette solution. Bath pH changes alone did not generate significant currents through SLC4A11, except immediately following exposure to NH4Cl. Reversal potential shifts in response to changing [NH3]o and pHo suggested an NH3/H(+)-coupled transport mode for SLC4A11. Proton flux through SLC4A11 in the absence of ammonia was relatively small, suggesting that ammonia transport is of more physiological relevance. Methylammonia produced currents similar to NH3 but with reduced amplitude. Estimated stoichiometry of SLC4A11 transport was 1:2 (NH3/H(+)). NH3-dependent currents were insensitive to 10 μM ethyl-isopropyl amiloride or 100 μM 4,4'- diisothiocyanatostilbene-2,2'-disulfonic acid. We propose that SLC4A11 is an NH3/2H(+) co-transporter exhibiting unique characteristics. DA - 2015/07/03/ PY - 2015 DO - 10.1074/jbc.M114.627455 DP - PubMed VL - 290 IS - 27 SP - 16894 EP - 16905 J2 - J. Biol. Chem. LA - eng SN - 1083-351X L2 - http://www.ncbi.nlm.nih.gov/pubmed/26018076 KW - ammonia KW - Ammonia KW - Anion Transport Proteins KW - Antiporters KW - Bicarbonates KW - cornea KW - electrophysiology KW - Humans KW - Hydrogen KW - Ion Transport KW - membrane transport KW - NH3 transport KW - NH4+ KW - proton transport KW - Protons KW - SLC4A11 KW - Symporters ER - TY - JOUR TI - Molecular Mechanisms Underlying the Corneal Endothelial Pump AU - Bonanno, Joseph A. T2 - Experimental Eye Research AB - The corneal endothelium is responsible for maintaining the hydration of the cornea. This is through a “Pump-Leak” mechanism where the active transport properties of the endothelium represent the “Pump” and the stromal swelling pressure represents the “Leak”. For the “Pump”, Na+,K+ ATPase activity and the presence of HCO3−, Cl−,and carbonic anhydrase activity are required. Several basolateral (stromal side) anion transporters, apical (facing the aqueous humor) ion channels and water channels have been identified that could support a model for ion secretion as the basis for the endothelial pump, however evidence of sustained anion fluxes, osmotic gradients or the need for water channels is lacking. This has prompted consideration of other models, such as Electro-osmosis, and consideration of metabolite flux as components of the endothelial pump. Although the conditions under which the “Pump” is supported are known, a complete model of the endothelial “Pump” has yet to emerge. DA - 2012/02// PY - 2012 DO - 10.1016/j.exer.2011.06.004 DP - PubMed Central VL - 95 IS - 1 SP - 2 EP - 7 J2 - Exp Eye Res SN - 0014-4835 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3199349/ Y2 - 2018/05/09/04:12:43 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3199349/pdf/nihms-310596.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3199349/ ER - TY - JOUR TI - Metabolic changes of the human donor cornea during organ-culture AU - Redbrake, C. AU - Salla, S. AU - Frantz, A. AU - Reim, M. T2 - Acta Ophthalmologica Scandinavica AB - PURPOSE: To study metabolic changes of the human cornea during organ-culture. Morphological changes have been extensively studied, whereas changes in human corneal metabolism have not been investigated yet. MATERIAL AND METHODS: 106 human corneas were stored for 1, 7, 15, 18, 21 and 28 days in a closed-system under standard eyebank conditions. After storage, glucose, lactate, ATP, ADP and AMP concentrations were determined in each cornea. RESULTS: Glucose concentration decreased during the first two weeks with a minimum on day 15. ATP and ADP concentrations increased during the same period of time, but had their minimum later, on day 18. Lactate increased during the culture period up to day 21 and decreased thereafter. CONCLUSION: From these data we conclude that the human cornea recovers during organ-culture, especially during the first two weeks. The changes occurring after a fortnight might be related to the artificial culture conditions. Nevertheless, the metabolic status is better than in post-mortem corneas. The changes may be partly avoided by changing the medium after at least two weeks of organ-culture. DA - 1999/06// PY - 1999 DP - PubMed VL - 77 IS - 3 SP - 266 EP - 272 J2 - Acta Ophthalmol Scand LA - eng SN - 1395-3907 L2 - http://www.ncbi.nlm.nih.gov/pubmed/10406143 KW - Adenine Nucleotides KW - Aged KW - Cornea KW - Corneal Transplantation KW - Eye Banks KW - Follow-Up Studies KW - Glucose KW - Humans KW - Lactic Acid KW - Luminescent Measurements KW - Middle Aged KW - Organ Culture Techniques KW - Organ Preservation KW - Time Factors KW - Tissue Donors ER - TY - JOUR TI - Steady State Levels of Glucose in the Different Layers of the Cornea, Aqueous Humor, Blood and Tears in vivo AU - Reim, M. AU - Lax, F. AU - Lichte, H. AU - Turss, R. T2 - Ophthalmologica DA - 1967/// PY - 1967 DO - 10.1159/000305147 DP - www.karger.com VL - 154 IS - 1 SP - 39 EP - 50 J2 - OPH LA - english SN - 0030-3755, 1423-0267 UR - https://www.karger.com/Article/FullText/305147 Y2 - 2018/05/08/20:19:19 L2 - http://www.ncbi.nlm.nih.gov/pubmed/6070025 L2 - https://www.karger.com/Article/Abstract/305147 ER - TY - JOUR TI - GLUT1 glucose transporter expression in the diabetic and nondiabetic human eye AU - Kumagai, A. K. AU - Glasgow, B. J. AU - Pardridge, W. M. T2 - Investigative Ophthalmology & Visual Science AB - PURPOSE: The GLUT1 glucose transporter is expressed in endothelial and epithelial barriers, including the retinal capillary endothelium and the retinal pigment epithelium (RPE) of the eye. The present studies were undertaken to determine whether GLUT1 is expressed in additional cell types within the human eye and whether retinal endothelial GLUT1 is aberrantly expressed in diabetic proliferative retinopathy in humans. METHODS: Immunohistochemical staining of sections of human eyes obtained at surgery or autopsy from patients with and without diabetes was performed with polyclonal antisera directed against the human GLUT1 glucose transporter. RESULTS: In the course of this study, an unexpected multicellular localization of GLUT1 in different cellular barriers of the human eye was observed. In the nondiabetic eye, specific staining for GLUT1 was seen in the nerve fiber layer, the ganglion and photoreceptor cell bodies, the capillaries and the RPE of the retina, the basal infoldings of the pigmented and nonpigmented layers of the ciliary body, the capillary endothelium and posterior epithelium of the iris, the corneal epithelium and endothelium, and the endothelium lining of the canal of Schlemm. Müller cells, a type of retinal glial cell identified by morphology and by parallel staining for glial fibrillary acidic protein, also stained intensely positive for GLUT1. The pattern of GLUT1 immunoreactivity in the diabetic eyes was virtually identical to that in the nondiabetic specimens, with the notable exception that the neovascular endothelium of proliferative retinopathy did not stain for GLUT1. CONCLUSIONS: These studies describe the heretofore unrecognized expression of immunoreactive GLUT1 in the ganglion cell layer of the retina, the endothelium lining the canal of Schlemm, the corneal endothelium, and the basal cells of the corneal epithelium of the human eye. The present study also provides evidence for immunoreactive GLUT1 in glial cells of the central nervous system. Because the expression of GLUT1 is characteristic of tissues that possess a barrier function, the absence of GLUT1 immunoreactivity in the neovascular tissue of proliferative diabetic retinopathy suggests that the loss of selective permeability is associated with an absence of facilitated glucose transport in this disorder. DA - 1994/05// PY - 1994 DP - PubMed VL - 35 IS - 6 SP - 2887 EP - 2894 J2 - Invest. Ophthalmol. Vis. Sci. LA - eng SN - 0146-0404 L2 - http://www.ncbi.nlm.nih.gov/pubmed/8188484 KW - Adult KW - Aged KW - Aged, 80 and over KW - Anterior Eye Segment KW - Child, Preschool KW - Diabetic Retinopathy KW - Endothelium, Vascular KW - Eye KW - Female KW - Humans KW - Immunoenzyme Techniques KW - Male KW - Middle Aged KW - Monosaccharide Transport Proteins KW - Pigment Epithelium of Eye KW - Retina KW - Retinal Neovascularization ER - TY - JOUR TI - Aquaporin water channels and endothelial cell function AU - Verkman, AS T2 - Journal of Anatomy AB - The aquaporins (AQP) are a family of homologous water channels expressed in many epithelial and endothelial cell types involved in fluid transport. AQP1 protein is strongly expressed in most microvascular endothelia outside of the brain, as well as in endothelial cells in cornea, intestinal lacteals, and other tissues. AQP4 is expressed in astroglial foot processes adjacent to endothelial cells in the central nervous system. Transgenic mice lacking aquaporins have been useful in defining their role in mammalian physiology. Mice lacking AQP1 manifest defective urinary concentrating ability, in part because of decreased water permeability in renal vasa recta microvessels. These mice also show a defect in dietary fat processing that may involve chylomicron absorption by intestinal lacteals, as well as defective active fluid transport across the corneal endothelium. AQP1 might also play a role in tumour angiogenesis and in renal microvessel structural adaptation. However, AQP1 in most endothelial tissues does not appear to have a physiological function despite its role in osmotically driven water transport. For example, mice lacking AQP1 have low alveolar-capillary water permeability but unimpaired lung fluid absorption, as well as unimpaired saliva and tear secretion, aqueous fluid outflow, and pleural and peritoneal fluid transport. In the central nervous system mice lacking AQP4 are partially protected from brain oedema in water intoxication and ischaemic models of brain injury. Therefore, although the role of aquaporins in epithelial fluid transport is in most cases well-understood, there remain many questions about the role of aquaporins in endothelial cell function. It is unclear why many leaky microvessels strongly express AQP1 without apparent functional significance. Improved understanding of aquaporin-endothelial biology may lead to novel therapies for human disease, such as pharmacological modulation of corneal fluid transport, renal fluid clearance and intestinal absorption. DA - 2002/06// PY - 2002 DO - 10.1046/j.1469-7580.2002.00058.x DP - PubMed Central VL - 200 IS - 6 SP - 617 EP - 627 J2 - J Anat SN - 0021-8782 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1570747/ Y2 - 2018/05/08/19:17:26 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1570747/pdf/joa0200-0617.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1570747/ ER - TY - JOUR TI - Fluid transport across cultured layers of corneal endothelium from aquaporin-1 null mice AU - Kuang, Kunyan AU - Yiming, Maimaiti AU - Wen, Quan AU - Li, Yansui AU - Ma, Li AU - Iserovich, Pavel AU - Verkman, A. S. AU - Fischbarg, Jorge T2 - Experimental Eye Research AB - We explored the role of AQP1, the only known aquaporin in corneal endothelium, on active fluid transport and passive osmotic water movements across corneal endothelial layers cultured from AQP1 null mice and wildtype mice. AQP1 null mice had grossly transparent corneas, just as wildtype mice. Endothelial cell layers grown on permeable supports transported fluid at rates of (in microl h(-1) cm(-2), n = 9 mean+/-s.e.): 4.3+/-0.6, wildtype mice (MCE); 3.5+/-0.6, AQP1 null mice (KMCE; difference not significant). The osmotic water flow (also in microl h(-1) cm(-2)) induced by a 100 mOsm sucrose gradient across MCE cell layers (8.7+/-0.6, n = 8) was significantly greater than that across KMCE (5.7+/-0.7, n = 6, p = 0.007). When plated on glass coverslips, plasma membrane osmotic water permeability determined by light scattering was significantly higher for cells from wildtype vs. AQP1 null mice (in microm sec(-1): 74+/-4, n = 19 vs. 44+/-4 microm sec(-1), n = 11, p < 0.001). Unexpectedly, after 10% hypo-osmotic challenge, the extent of the regulatory volume recovery was significantly reduced for AQP1 null mice cells (in%: MCE controls, 99+/-1, n = 19 vs. KMCE: 64+/-5, n = 11, p < 0.001). Thus, as in other 'low rate' fluid transporting epithelia, deletion of AQP1 in mice corneal endothelium reduces osmotic water permeability but not active transendothelial fluid transport. However, that deletion impaired the extent of regulatory volume decrease after a hypo-osmotic challenge, suggesting a novel role for AQP1 in corneal endothelium. DA - 2004/04// PY - 2004 DO - 10.1016/j.exer.2003.11.017 DP - PubMed VL - 78 IS - 4 SP - 791 EP - 798 J2 - Exp. Eye Res. LA - eng SN - 0014-4835 L2 - http://www.ncbi.nlm.nih.gov/pubmed/15037113 KW - Animals KW - Aquaporin 1 KW - Aquaporins KW - Cell Membrane KW - Cell Size KW - Endothelial Cells KW - Endothelium, Corneal KW - Immunohistochemistry KW - Mice KW - Mice, Knockout KW - Water-Electrolyte Balance ER - TY - JOUR TI - Vimentin enhances cell elastic behavior and protects against compressive stress AU - Mendez, M. G. AU - Restle, D. AU - Janmey, P. A. T2 - Biophysical Journal AB - Vimentin intermediate filament expression is a hallmark of epithelial-to-mesenchymal transitions, and vimentin is involved in the maintenance of cell mechanical properties, cell motility, adhesion, and other signaling pathways. A common feature of vimentin-expressing cells is their routine exposure to mechanical stress. Intermediate filaments are unique among cytoskeletal polymers in resisting large deformations in vitro, yet vimentin's mechanical role in the cell is not clearly understood. We use atomic force microscopy to compare the viscoelastic properties of normal and vimentin-null (vim(-/-)) mouse embryo fibroblasts (mEFs) on substrates of different stiffnesses, spread to different areas, and subjected to different compression patterns. In minimally perturbed mEF, vimentin contributes little to the elastic modulus at any indentation depth in cells spread to average areas. On a hard substrate however, the elastic moduli of maximally spread mEFs are greater than those of vim(-/-)mEF. Comparison of the plastic deformation resulting from controlled compression of the cell cortex shows that vimentin's enhancement of elastic behavior increases with substrate stiffness. The elastic moduli of normal mEFs are more stable over time than those of vim(-/-)mEFs when cells are subject to ongoing oscillatory compression, particularly on a soft substrate. In contrast, increasing compressive strain over time shows a greater role for vimentin on a hard substrate. Under both conditions, vim(-/-)mEFs exhibit more variable responses, indicating a loss of regulation. Finally, normal mEFs are more contractile in three-dimensional collagen gels when seeded at low density, when cell-matrix contacts dominate, whereas contractility of vim(-/-)mEF is greater at higher densities when cell-cell contacts are abundant. Addition of fibronectin to gel constructs equalizes the contractility of the two cell types. These results show that the Young's moduli of normal and vim(-/-)mEFs are substrate stiffness dependent even when the spread area is similar, and that vimentin protects against compressive stress and preserves mechanical integrity by enhancing cell elastic behavior. DA - 2014/07/15/ PY - 2014 DO - 10.1016/j.bpj.2014.04.050 DP - PubMed VL - 107 IS - 2 SP - 314 EP - 323 J2 - Biophys. J. LA - eng SN - 1542-0086 L2 - http://www.ncbi.nlm.nih.gov/pubmed/25028873 KW - Actin Cytoskeleton KW - Animals KW - Cell Line KW - Compressive Strength KW - Elastic Modulus KW - Fibroblasts KW - Mice KW - Vimentin KW - Viscosity ER - TY - JOUR TI - 3D map of the human corneal endothelial cell AU - He, Zhiguo AU - Forest, Fabien AU - Gain, Philippe AU - Rageade, Damien AU - Bernard, Aurélien AU - Acquart, Sophie AU - Peoc’h, Michel AU - Defoe, Dennis M. AU - Thuret, Gilles T2 - Scientific Reports AB - Corneal endothelial cells (CECs) are terminally differentiated cells, specialized in regulating corneal hydration and transparency. They are highly polarized flat cells that separate the cornea from the aqueous humor. Their apical surface, in contact with aqueous humor is hexagonal, whereas their basal surface is irregular. We characterized the structure of human CECs in 3D using confocal microscopy of immunostained whole corneas in which cells and their interrelationships remain intact. Hexagonality of the apical surface was maintained by the interaction between tight junctions and a submembraneous network of actomyosin, braced like a drum. Lateral membranes, which support enzymatic pumps, presented complex expansions resembling interdigitated foot processes at the basal surface. Using computer-aided design and drafting software, we obtained a first simplified 3D model of CECs. By comparing their expression with those in epithelial, stromal and trabecular corneal cells, we selected 9 structural or functional proteins for which 3D patterns were specific to CECs. This first 3D map aids our understanding of the morphologic and functional specificity of CECs and could be used as a reference for characterizing future cell therapy products destined to treat endothelial dysfunctions. DA - 2016/07/06/ PY - 2016 DO - 10.1038/srep29047 DP - www.nature.com VL - 6 SP - 29047 LA - en SN - 2045-2322 UR - https://www.nature.com/articles/srep29047 Y2 - 2018/05/07/18:57:20 L1 - https://www.nature.com/articles/srep29047.pdf L2 - https://www.nature.com/articles/srep29047 ER - TY - BOOK TI - Molecular Biology of Eye Disease AU - Hejtmancik, J. Fielding AU - Nickerson, John M. AB - This volume of Progress in Molecular Biology and Translational Science focuses on the molecular biology of eye disease.Contributions from leading authorities Informs and updates on all the latest developments in the field DA - 2015/08/13/ PY - 2015 DP - Google Books SP - 573 LA - en PB - Academic Press SN - 978-0-12-801267-3 L2 - https://books.google.com.co/books?id=jeicBAAAQBAJ KW - Science / Life Sciences / Molecular Biology KW - Science / Life Sciences / Neuroscience ER - TY - CHAP TI - Chapter 1 - Anatomy of the eye and orbit AU - Forrester, John V. AU - Dick, Andrew D. AU - McMenamin, Paul G. AU - Roberts, Fiona AU - Pearlman, Eric T2 - The Eye (Fourth Edition) DA - 2016/// PY - 2016 DP - ScienceDirect SP - 1 EP - 102.e2 PB - W.B. Saunders SN - 978-0-7020-5554-6 UR - https://www.sciencedirect.com/science/article/pii/B9780702055546000010 Y2 - 2018/05/03/02:38:01 L2 - https://www.sciencedirect.com/science/article/pii/B9780702055546000010 ER - TY - JOUR TI - High glucose alters apoptosis and proliferation in HEK293 cells by inhibition of cloned BKCa channel AU - Chang, Hui AU - Ma, Yu-Guang AU - Wang, Yun-Ying AU - Song, Zhen AU - Li, Quan AU - Yang, Ning AU - Zhao, Hua-Zhou AU - Feng, Han-Zhong AU - Chang, Yao-Ming AU - Ma, Jin AU - Yu, Zhi-Bin AU - Xie, Man-Jiang T2 - Journal of Cellular Physiology DA - 2011/06/01/ PY - 2011 DO - 10.1002/jcp.22497 DP - onlinelibrary.wiley.com VL - 226 IS - 6 SP - 1660 EP - 1675 LA - en SN - 1097-4652 UR - https://onlinelibrary.wiley.com/doi/abs/10.1002/jcp.22497 Y2 - 2018/05/03/02:07:35 L2 - https://onlinelibrary.wiley.com/doi/pdf/10.1002/jcp.22497 ER - TY - JOUR TI - Corneal integrins and their functions AU - Stepp, Mary Ann T2 - Experimental Eye Research AB - Integrins were first described just over 20 years ago and have been studied in the cornea by many groups interested in how the cornea functions in health and disease. There are a minimum of 12 different integrin heterodimers reported to be expressed by the major resident cells of the cornea: the corneal and limbal epithelial cells, keratocytes/fibroblasts, and corneal endothelial cells. These different integrin heterodimers play important and varied roles in maintaining the cornea and organizing how its cells interact with their surrounding extracellular matrix to maintain corneal clarity. In this review, an overview of the discovery and functions of integrins is provided along with a description of the current state of our knowledge of this large family of important proteins. While we have learned a lot about corneal integrins over the past 20 years, there is still much to learn. Areas where gaps in our knowledge of integrin functions in the cornea are slowing our progress in understanding corneal diseases and dystrophies at a molecular level are highlighted. DA - 2006/07// PY - 2006 DO - 10.1016/j.exer.2006.01.010 DP - PubMed VL - 83 IS - 1 SP - 3 EP - 15 J2 - Exp. Eye Res. LA - eng SN - 0014-4835 L2 - http://www.ncbi.nlm.nih.gov/pubmed/16580666 KW - Cell Adhesion KW - Cornea KW - Endothelial Cells KW - Epithelial Cells KW - Extracellular Matrix KW - Fibroblasts KW - Humans KW - Integrins KW - Models, Biological KW - Wound Healing ER - TY - JOUR TI - Regeneración de la superficie ocular: stem cells/células madre y técnicas reconstructivas AU - Fernández, A. AU - Moreno, J. AU - Prósper, F. AU - García, M. AU - Echeveste, J. T2 - Anales del Sistema Sanitario de Navarra DA - 2008/04// PY - 2008 DP - SciELO VL - 31 IS - 1 SP - 53 EP - 69 J2 - Anales Sis San Navarra SN - 1137-6627 ST - Regeneración de la superficie ocular UR - http://scielo.isciii.es/scielo.php?script=sci_abstract&pid=S1137-66272008000100005&lng=es&nrm=iso&tlng=es Y2 - 2018/05/02/14:27:44 L1 - http://scielo.isciii.es/pdf/asisna/v31n1/revision.pdf L2 - http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S1137-66272008000100005 ER - TY - JOUR TI - Aqueous Humor Dynamics: A Review AU - Goel, Manik AU - Picciani, Renata G AU - Lee, Richard K AU - Bhattacharya, Sanjoy K T2 - The Open Ophthalmology Journal AB - Glaucoma is a family of optic neuropathies which cause irreversible but potentially preventable vision loss. Vision loss in most forms of glaucoma is related to elevated IOP with subsequent injury to the optic nerve. Secretion of aqueous humor and regulation of its outflow are physiologically important processes for maintaining IOP in the normal range. Thus, understanding the complex mechanisms that regulate aqueous humor circulation is essential for management of glaucoma. The two main structures related to aqueous humor dynamics are the ciliary body and the trabecular meshwork (TM). Three mechanisms are involved in aqueous humor formation: diffusion, ultrafiltration and active secretion. Active secretion is the major contributor to aqueous humor formation. The aqueous humor flow in humans follows a circadian rhythm, being higher in the morning than at night. The aqueous humor leaves the eye by passive flow via two pathways - the trabecular meshwork and the uveoscleral pathway. In humans, 75% of the resistance to aqueous humor outflow is localized within the TM with the juxtacanalicular portion of the TM being the main site of outflow resistance. Glycosaminoglycan deposition in the TM extracellular matrix (ECM) has been suggested to be responsible for increased outflow resistance at this specific site whereas others have suggested deposition of proteins, such as cochlin, obstruct the aqueous humor outflow through the TM. The uveoscleral outflow pathway is relatively independent of the intraocular pressure and the proportion of aqueous humor exiting the eye via the uveoscleral pathway decreases with age. DA - 2010/09/03/ PY - 2010 DO - 10.2174/1874364101004010052 DP - PubMed Central VL - 4 SP - 52 EP - 59 J2 - Open Ophthalmol J SN - 1874-3641 ST - Aqueous Humor Dynamics UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3032230/ Y2 - 2018/05/02/03:36:27 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3032230/pdf/TOOPHTJ-4-52.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3032230/ ER - TY - CHAP TI - Cornea and Sclera AU - Dawson, D G. AU - John L. U AU - Henry F. Edelhauser T2 - Adler's Physiology of the Eye DA - 2011/// PY - 2011 ET - 11th Edition PB - W B Saunders Company SN - 978-0-323-05714-1 978-0-323-08116-0 UR - https://www.elsevier.com/books/adlers-physiology-of-the-eye/levin/978-0-323-05714-1 Y2 - 2018/05/02/02:21:35 L2 - https://www.elsevier.com/books/adlers-physiology-of-the-eye/levin/978-0-323-05714-1 ER - TY - BOOK TI - Cornea AU - Güell, J. L. AB - Over the past ten years tremendous progress has been achieved in corneal surgery. This volume – the 6th in the 'ESASO Course Series' – reflects the most relevant topics ranging from basic knowledge to the most advanced techniques. It covers the functional anatomy with medical and surgical management of the ocular surface, provides information on high-risk corneal transplantation and explains techniques such as corneal collagen crosslinking, femtosecond laser-assisted penetrating, deep anterior lamellar keratoplasty (DALK) and descemet membrane endothelial keratoplasty (DMEK). Further contributions describe how to manage astigmatism after corneal transplantation as well as indications of intrastroma corneal ring segments (ICRS) in keratoconus. Well-known corneal and ocular surface surgeons and refractive surgery specialists share their experience in this publication, making it a must-read for every anterior segment surgeon, especially those performing corneal surgery and using corneal refractive procedures. DA - 2015/08/11/ PY - 2015 DP - Google Books SP - 138 LA - en PB - Karger Medical and Scientific Publishers SN - 978-3-318-05453-8 L2 - https://books.google.com.co/books?id=_2prCgAAQBAJ KW - Medical / Immunology KW - Medical / Ophthalmology ER - TY - CHAP TI - Chapter 4 - Biochemistry and cell biology AU - Forrester, John V. AU - Dick, Andrew D. AU - McMenamin, Paul G. AU - Roberts, Fiona AU - Pearlman, Eric T2 - The Eye (Fourth Edition) DA - 2016/// PY - 2016 DP - ScienceDirect SP - 157 EP - 268.e4 PB - W.B. Saunders SN - 978-0-7020-5554-6 UR - https://www.sciencedirect.com/science/article/pii/B9780702055546000046 Y2 - 2018/05/01/23:26:43 L2 - https://www.sciencedirect.com/science/article/pii/B9780702055546000046 ER - TY - ELEC TI - Untitled Document UR - http://med.javeriana.edu.co/oftalmologia/materiales/refraccion.htm Y2 - 2018/05/01/22:20:36 L2 - http://med.javeriana.edu.co/oftalmologia/materiales/refraccion.htm ER - TY - BOOK TI - Cornea E-Book AU - Mannis, Mark J. AU - Holland, Edward J. AB - Highly praised in its first three editions, Cornea has become a market-leading cornerstone text and the immediate go-to resource for anyone working in this hugely popular and evolving sub-specialty. Offered over two volumes and featuring the knowledge of over 200 experts worldwide, it presents state-of-the-art coverage of the expanding range of contemporary corneal surgery, new diagnostic technology, and medical management of corneal and external disease as well as ocular surface disease. This updated edition includes 20 brand-new chapters, while an enhanced focus on images provides key visual guidance in this challenging field.Exceptionally clear illustrations, diagnostic images, and step-by-step surgical photographs offer superb visual guidance.20 brand-new chapters cover the latest advances in the field, such as DMEK, Ultra-Thin DSEK and DSAEK techniques; endothelial cell transplantation; keratoplasty and prosthokeratoplasty techniques; collagen cross-linking; and new refractive surgical techniques (presbyopic implants and SMILE surgery).Boasts over 170 chapters with unique, cutting-edge content, as well as 2,300 clear illustrations – 670 of which are new to this edition. Presents a detailed exposition of the growing number of techniques for lamellar keratoplasty, including outcomes.Includes new sections on the latest developments in the management of ocular surface disease.Key point overviews in each chapter offer easier access to crucial information. DA - 2016/09/23/ PY - 2016 DP - Google Books SP - 2189 LA - en PB - Elsevier Health Sciences SN - 978-0-323-35758-6 L2 - https://books.google.com.co/books?id=ywwlDQAAQBAJ KW - Medical / Ophthalmology ER - TY - JOUR TI - Correlation of Histologic Corneal Endothelial Cell Counts With Specular Microscopic Cell Density AU - Williams, K. Keven AU - Noe, Robin L. AU - Grossniklaus, Hans E. AU - Drews-Botsch, Carolyn AU - Edelhauser, Henry F. T2 - Archives of Ophthalmology AB -

• The central endothelia of 48 eye bank corneas from donors ranging in age from 5 weeks to 88 years were photographed using in vitro specular microscopy. Computer-assisted morphometric analysis of the size and shape of endothelial cells was performed, and cell density was calculated. Histologic examination of the corneas after specular microscopy determined endothelial cell counts using ×40 objective magnification. The mean endothelial cell counts from five different high-power fields were calculated. Results showed that there is a direct correlation between cell number and specular microscopy cell density (r=.91 and Spearman rank correlation, 0.69; both significant atP<.01). A nomogram was developed to estimate corneal endothelial cell density from high-power field cell counts of pathologic specimens.

DA - 1992/08/01/ PY - 1992 DO - 10.1001/archopht.1992.01080200126039 DP - jamanetwork.com VL - 110 IS - 8 SP - 1146 EP - 1149 J2 - Arch Ophthalmol LA - en SN - 0003-9950 UR - https://jamanetwork.com/journals/jamaophthalmology/fullarticle/639808 Y2 - 2018/05/01/20:44:16 L2 - https://jamanetwork.com/journals/jamaophthalmology/article-abstract/639808?redirect=true ER - TY - JOUR TI - pH-regulated Slo3 K+ Channels: Properties of Unitary Currents AU - Zhang, Xue AU - Zeng, Xuhui AU - Xia, Xiao-Ming AU - Lingle, Christopher J. T2 - The Journal of General Physiology AB - Here we have examined the voltage and pH dependence of unitary Slo3 channels and used analysis of current variance to define Slo3 unitary current properties over a broader range of voltages. Despite complexity in Slo3 channel openings that precludes simple definition of the unitary conductance, average current through single Slo3 channels varies linearly with voltage at positive activation potentials. Furthermore, the average Slo3 unitary current at a given activation potential does not change with pH. Consistent with macroscopic conductance estimates, the apparent open probability of Slo3 channel exhibits a pH-dependent maximum, with limiting values around 0.3 at the most elevated pH and voltage. Estimates of Slo3 conductance at negative potentials support a weaker intrinsic voltage dependence of gating than is observed for Slo1. For the pH-regulated Slo3 K+ channel, the dependence of macroscopic conductance on pH suggests that the pH-sensitive mechanism regulates gating in an allosteric manner qualitatively similar to regulation of Slo1 by Ca2+. Together, the results support the view that the regulation of macroscopic Slo3 currents by pH reflects regulation of gating equilibria, and not a direct effect of pH on ion permeation. Specifically, both voltage and pH regulate a closed–open conformational change in a largely independent fashion. DA - 2006/09// PY - 2006 DO - 10.1085/jgp.200609551 DP - PubMed Central VL - 128 IS - 3 SP - 301 EP - 315 J2 - J Gen Physiol SN - 0022-1295 ST - pH-regulated Slo3 K+ Channels UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2151565/ Y2 - 2018/04/30/23:27:09 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2151565/pdf/jgp1280301.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2151565/ ER - TY - JOUR TI - RNA toxicity and missplicing in the common eye disease fuchs endothelial corneal dystrophy AU - Du, Jintang AU - Aleff, Ross A. AU - Soragni, Elisabetta AU - Kalari, Krishna AU - Nie, Jinfu AU - Tang, Xiaojia AU - Davila, Jaime AU - Kocher, Jean-Pierre AU - Patel, Sanjay V. AU - Gottesfeld, Joel M. AU - Baratz, Keith H. AU - Wieben, Eric D. T2 - The Journal of Biological Chemistry AB - Fuchs endothelial corneal dystrophy (FECD) is an inherited degenerative disease that affects the internal endothelial cell monolayer of the cornea and can result in corneal edema and vision loss in severe cases. FECD affects ∼5% of middle-aged Caucasians in the United States and accounts for >14,000 corneal transplantations annually. Among the several genes and loci associated with FECD, the strongest association is with an intronic (CTG·CAG)n trinucleotide repeat expansion in the TCF4 gene, which is found in the majority of affected patients. Corneal endothelial cells from FECD patients harbor a poly(CUG)n RNA that can be visualized as RNA foci containing this condensed RNA and associated proteins. Similar to myotonic dystrophy type 1, the poly(CUG)n RNA co-localizes with and sequesters the mRNA-splicing factor MBNL1, leading to missplicing of essential MBNL1-regulated mRNAs. Such foci and missplicing are not observed in similar cells from FECD patients who lack the repeat expansion. RNA-Seq splicing data from the corneal endothelia of FECD patients and controls reveal hundreds of differential alternative splicing events. These include events previously characterized in the context of myotonic dystrophy type 1 and epithelial-to-mesenchymal transition, as well as splicing changes in genes related to proposed mechanisms of FECD pathogenesis. We report the first instance of RNA toxicity and missplicing in a common non-neurological/neuromuscular disease associated with a repeat expansion. The FECD patient population with this (CTG·CAG)n trinucleotide repeat expansion exceeds that of the combined number of patients in all other microsatellite expansion disorders. DA - 2015/03/06/ PY - 2015 DO - 10.1074/jbc.M114.621607 DP - PubMed VL - 290 IS - 10 SP - 5979 EP - 5990 J2 - J. Biol. Chem. LA - eng SN - 1083-351X L2 - http://www.ncbi.nlm.nih.gov/pubmed/25593321 KW - Alternative Splicing KW - Basic Helix-Loop-Helix Leucine Zipper Transcription Factors KW - Cornea KW - Eye KW - Fuchs Corneal Dystrophy KW - Fuchs' Endothelial Dystrophy KW - Humans KW - RNA Foci KW - RNA Splicing KW - RNA Toxicity KW - RNA-Binding Proteins KW - RNA, Messenger KW - Transcription Factor 4 KW - Transcription Factors KW - Trinucleotide Repeat Disease KW - Trinucleotide Repeat Expansion ER - TY - JOUR TI - Transcriptomic Profiling of Posterior Polymorphous Corneal Dystrophy AU - Chung, Doug D. AU - Frausto, Ricardo F. AU - Lin, Benjamin R. AU - Hanser, Evelyn M. AU - Cohen, Zack AU - Aldave, Anthony J. T2 - Investigative Ophthalmology & Visual Science AB - Purpose: To investigate the molecular basis of posterior polymorphous corneal dystrophy (PPCD) by examining the PPCD transcriptome and the effect of decreased ZEB1 expression on corneal endothelial cell (CEnC) gene expression. Methods: Next-generation RNA sequencing (RNA-seq) analyses of corneal endothelium from two PPCD-affected individuals (one with PPCD3 and one of unknown genetic cause) compared with two age-matched controls, and primary human CEnC (pHCEnC) transfected with siRNA-mediated ZEB1 knockdown. The expression of selected differentially expressed genes was validated by quantitative polymerase chain reaction (qPCR) and/or assessed by in situ hybridization in the corneal endothelium of four independent cases of PPCD (one with PPCD3 and three of unknown genetic cause). Results: Expression of 16% and 46% of the 104 protein-coding genes specific to ex vivo corneal endothelium was lost in the endothelium of two individuals with PPCD. Thirty-two genes associated with ZEB1 and 3 genes (BMP4, CCND1, ZEB1) associated with OVOL2 were differentially expressed in the same direction in both individuals with PPCD. Immunohistochemistry staining and RNA-seq analyses demonstrated variable expression of type IV collagens in PPCD corneas. Decreasing ZEB1 expression in pHCEnC altered expression of 711 protein-coding genes, many of which are associated with canonical pathways regulating various cellular processes. Conclusions: Identification of the altered transcriptome in PPCD and in a cell-based model of PPCD provided insight into the molecular alterations characterizing PPCD. Further study of the differentially expressed genes associated with ZEB1 and OVOL2 is expected to identify candidate genes for individuals with PPCD and without a ZEB1 or OVOL2 mutation. DA - 2017//06/01 PY - 2017 DO - 10.1167/iovs.17-21423 DP - PubMed VL - 58 IS - 7 SP - 3202 EP - 3214 J2 - Invest. Ophthalmol. Vis. Sci. LA - eng SN - 1552-5783 L2 - http://www.ncbi.nlm.nih.gov/pubmed/28654985 KW - Adolescent KW - Adult KW - Case-Control Studies KW - Collagen KW - Collagen Type IV KW - Corneal Dystrophies, Hereditary KW - Endothelial Cells KW - Endothelium, Corneal KW - Female KW - Gene Expression Profiling KW - Humans KW - Immunohistochemistry KW - Male KW - Polymerase Chain Reaction KW - Transcriptome KW - Young Adult KW - Zinc Finger E-box-Binding Homeobox 1 ER - TY - JOUR TI - Identification of novel molecular markers through transcriptomic analysis in human fetal and adult corneal endothelial cells AU - Chen, Yinyin AU - Huang, Kevin AU - Nakatsu, Martin N. AU - Xue, Zhigang AU - Deng, Sophie X. AU - Fan, Guoping T2 - Human Molecular Genetics AB - The corneal endothelium is composed of a monolayer of corneal endothelial cells (CECs), which is essential for maintaining corneal transparency. To better characterize CECs in different developmental stages, we profiled mRNA transcriptomes in human fetal and adult corneal endothelium with the goal to identify novel molecular markers in these cells. By comparing CECs with 12 other tissue types, we identified 245 and 284 signature genes that are highly expressed in fetal and adult CECs, respectively. Functionally, these genes are enriched in pathways characteristic of CECs, including inorganic anion transmembrane transporter, extracellular matrix structural constituent and cyclin-dependent protein kinase inhibitor activity. Importantly, several of these genes are disease target genes in hereditary corneal dystrophies, consistent with their functional significance in CEC physiology. We also identified stage-specific markers associated with CEC development, such as specific members in the transforming growth factor beta and Wnt signaling pathways only expressed in fetal, but not in adult CECs. Lastly, by the immunohistochemistry of ocular tissues, we demonstrated the unique protein localization for Wnt5a, S100A4, S100A6 and IER3, the four novel markers for fetal and adult CECs. The identification of a new panel of stage-specific markers for CECs would be very useful for characterizing CECs derived from stem cells or ex vivo expansion for cell replacement therapy. DA - 2013/04/01/ PY - 2013 DO - 10.1093/hmg/dds527 DP - PubMed VL - 22 IS - 7 SP - 1271 EP - 1279 J2 - Hum. Mol. Genet. LA - eng SN - 1460-2083 L2 - http://www.ncbi.nlm.nih.gov/pubmed/23257286 KW - Apoptosis Regulatory Proteins KW - Biomarkers KW - Cells, Cultured KW - Endothelial Cells KW - Endothelium, Corneal KW - Eye Proteins KW - Fetus KW - Gene Expression Profiling KW - Humans KW - Membrane Proteins KW - Organ Specificity KW - Proto-Oncogene Proteins KW - RNA, Messenger KW - S100 Proteins KW - Transcriptome KW - Wnt Proteins KW - Wnt Signaling Pathway KW - Wnt-5a Protein ER - TY - JOUR TI - Functional Human Corneal Equivalents Constructed from Cell Lines AU - Griffith, May AU - Osborne, Rosemarie AU - Munger, Rejean AU - Xiong, Xiaojuan AU - Doillon, Charles J. AU - Laycock, Noelani L. C. AU - Hakim, Malik AU - Song, Ying AU - Watsky, Mitchell A. T2 - Science AB -

Human corneal equivalents comprising the three main layers of the cornea (epithelium, stroma, and endothelium) were constructed. Each cellular layer was fabricated from immortalized human corneal cells that were screened for use on the basis of morphological, biochemical, and electrophysiological similarity to their natural counterparts. The resulting corneal equivalents mimicked human corneas in key physical and physiological functions, including morphology, biochemical marker expression, transparency, ion and fluid transport, and gene expression. Morphological and functional equivalents to human corneas that can be produced in vitro have immediate applications in toxicity and drug efficacy testing, and form the basis for future development of implantable tissues.

DA - 1999/12/10/ PY - 1999 DO - 10.1126/science.286.5447.2169 DP - science.sciencemag.org VL - 286 IS - 5447 SP - 2169 EP - 2172 LA - en SN - 0036-8075, 1095-9203 UR - http://science.sciencemag.org/content/286/5447/2169 Y2 - 2018/04/30/22:59:12 L2 - http://www.ncbi.nlm.nih.gov/pubmed/10591651 L2 - http://science.sciencemag.org/content/286/5447/2169.full ER - TY - CHAP TI - Chapter Six - Calcium-Activated Potassium Channels: Potential Target for Cardiovascular Diseases AU - Dong, De-Li AU - Bai, Yun-Long AU - Cai, Ben-Zhi T2 - Advances in Protein Chemistry and Structural Biology A2 - Donev, Rossen T3 - Ion channels as therapeutic targets, part B AB - Ca2+-activated K+ channels (KCa) are classified into three subtypes: big conductance (BKCa), intermediate conductance (IKCa), and small conductance (SKCa) KCa channels. The three types of KCa channels have distinct physiological or pathological functions in cardiovascular system. BKCa channels are mainly expressed in vascular smooth muscle cells (VSMCs) and inner mitochondrial membrane of cardiomyocytes, activation of BKCa channels in these locations results in vasodilation and cardioprotection against cardiac ischemia. IKCa channels are expressed in VSMCs, endothelial cells, and cardiac fibroblasts and involved in vascular smooth muscle proliferation, migration, vessel dilation, and cardiac fibrosis. SKCa channels are widely expressed in nervous and cardiovascular system, and activation of SKCa channels mainly contributes membrane hyperpolarization. In this chapter, we summarize the physiological and pathological roles of the three types of KCa channels in cardiovascular system and put forward the possibility of KCa channels as potential target for cardiovascular diseases. DA - 2016/01/01/ PY - 2016 DP - ScienceDirect VL - 104 SP - 233 EP - 261 PB - Academic Press ST - Chapter Six - Calcium-Activated Potassium Channels UR - http://www.sciencedirect.com/science/article/pii/S1876162315000954 Y2 - 2018/04/30/22:55:31 KW - Big conductance Ca-activated K channels KW - Heart KW - Intermediate conductance Ca-activated K channels KW - Small conductance Ca-activated K channels KW - Vascular endothelial cells KW - Vascular smooth muscle cells ER - TY - ELEC TI - Slack, Slick, and Sodium-Activated Potassium Channels AU - Kaczmarek, Leonard K. T2 - International Scholarly Research Notices AB - The Slack and Slick genes encode potassium channels that are very widely expressed in the central nervous system. These channels are activated by elevations in intracellular sodium, such as those that occur during trains of one or more action potentials, or following activation of nonselective cationic neurotransmitter receptors such as AMPA receptors. This review covers the cellular and molecular properties of Slack and Slick channels and compares them with findings on the properties of sodium-activated potassium currents (termed KNa currents) in native neurons. Human mutations in Slack channels produce extremely severe defects in learning and development, suggesting that KNa channels play a central role in neuronal plasticity and intellectual function. DA - 2013/// PY - 2013 LA - en M3 - Research article UR - https://www.hindawi.com/journals/isrn/2013/354262/ Y2 - 2018/04/30/02:28:23 L1 - http://downloads.hindawi.com/archive/2013/354262.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/24319675 L4 - https://www.hindawi.com/journals/isrn/2013/354262/ ER - TY - JOUR TI - Overview of the Cornea: Structure, Function, and Development AU - Eghrari, Allen O. AU - Riazuddin, S. Amer AU - Gottsch, John D. T2 - Progress in Molecular Biology and Translational Science DA - 2015/// PY - 2015 DO - 10.1016/bs.pmbts.2015.04.001 DP - jhu.pure.elsevier.com VL - 134 SP - 7 EP - 23 J2 - Progress in molecular biology and translational science LA - English (US) SN - 1877-1173 ST - Overview of the Cornea UR - https://jhu.pure.elsevier.com/en/publications/overview-of-the-cornea-structure-function-and-development-8 Y2 - 2018/04/16/22:32:47 L2 - http://www.ncbi.nlm.nih.gov/pubmed/26310146 L2 - https://jhu.pure.elsevier.com/en/publications/overview-of-the-cornea-structure-function-and-development-8 ER - TY - JOUR TI - Expression and function of receptors for advanced glycation end products in bovine corneal endothelial cells AU - Kaji, Yuichi AU - Amano, Shiro AU - Usui, Tomohiko AU - Oshika, Tetsuro AU - Yamashiro, Kenji AU - Ishida, Susumu AU - Suzuki, Kaori AU - Tanaka, Sumiyoshi AU - Adamis, Anthony P. AU - Nagai, Ryoji AU - Horiuchi, Seiko T2 - Investigative Ophthalmology & Visual Science AB - PURPOSE: The corneal endothelium is a target of the aging process. This study was undertaken to reveal the relationship between corneal endothelial cell (CEC) death and the accumulation of advanced glycation end products (AGEs), by investigating the possible mechanism of accumulation of AGE in CECs and its effects on CEC death. METHODS: First, the in vivo expression of the receptor was investigated for AGE (RAGE) and galectin-3, both receptors for AGE, at both the mRNA and protein levels. Second, AGEs were added to the culture media of the cultured CECs, and the uptake of AGEs, the generation of reactive oxygen species, and the induction of apoptosis were investigated. RESULTS: Immunohistochemistry and RT-PCR demonstrated that both RAGE and galectin-3 were expressed in bovine CECs. After administration of AGE-modified bovine serum albumin to the culture medium, uptake of AGE was observed in the cytoplasm of the cultured bovine CECs. In addition, with increasing concentration of AGEs, the generation of reactive oxygen and the number of apoptotic cells also increased. CONCLUSIONS: These results show that the accumulation of AGEs in CECs induced apoptosis, in part, by increasing cellular oxidative stress. The accumulation of AGEs in the CECs of elderly patients may be involved in the loss of CECs during the aging process. DA - 2003/02// PY - 2003 DP - PubMed VL - 44 IS - 2 SP - 521 EP - 528 J2 - Invest. Ophthalmol. Vis. Sci. LA - eng SN - 0146-0404 L2 - http://www.ncbi.nlm.nih.gov/pubmed/12556378 KW - Animals KW - Apoptosis KW - Base Sequence KW - Cattle KW - Cells, Cultured KW - Endothelium, Corneal KW - Galectin 3 KW - Glycation End Products, Advanced KW - Humans KW - Immunoenzyme Techniques KW - Mice KW - Molecular Sequence Data KW - Rabbits KW - Reactive Oxygen Species KW - Receptor for Advanced Glycation End Products KW - Receptors, Immunologic KW - Receptors, Mitogen KW - Reverse Transcriptase Polymerase Chain Reaction KW - RNA, Messenger KW - Sequence Homology, Nucleic Acid KW - Serum Albumin, Bovine ER - TY - JOUR TI - Involvement of advanced glycation end products, oxidative stress and nuclear factor-kappaB in the development of diabetic keratopathy AU - Kim, Junghyun AU - Kim, Chan-Sik AU - Sohn, Eunjin AU - Jeong, Il-Ha AU - Kim, Hyojun AU - Kim, Jin Sook T2 - Graefe's Archive for Clinical and Experimental Ophthalmology DA - 2011/04// PY - 2011 DO - 10.1007/s00417-010-1573-9 DP - Crossref VL - 249 IS - 4 SP - 529 EP - 536 LA - en SN - 0721-832X, 1435-702X UR - http://link.springer.com/10.1007/s00417-010-1573-9 Y2 - 2018/11/02/15:41:51 ER - TY - JOUR TI - Mitochondrial and Morphologic Alterations in Native Human Corneal Endothelial Cells Associated With Diabetes Mellitus AU - Aldrich, Benjamin T. AU - Schlötzer-Schrehardt, Ursula AU - Skeie, Jessica M. AU - Burckart, Kimberlee A. AU - Schmidt, Gregory A. AU - Reed, Cynthia R. AU - Zimmerman, M. Bridget AU - Kruse, Friedrich E. AU - Greiner, Mark A. T2 - Investigative Opthalmology & Visual Science DA - 2017/04/10/ PY - 2017 DO - 10.1167/iovs.16-21094 DP - Crossref VL - 58 IS - 4 SP - 2130 LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?doi=10.1167/iovs.16-21094 Y2 - 2018/11/02/15:06:59 ER - TY - ELEC TI - Chloride channels | Ion channels | IUPHAR/BPS Guide to PHARMACOLOGY UR - http://www.guidetopharmacology.org/GRAC/FamilyDisplayForward?familyId=120 Y2 - 2018/10/27/04:00:14 L2 - http://www.guidetopharmacology.org/GRAC/FamilyDisplayForward?familyId=120 ER - TY - JOUR TI - Chloride channels T2 - British Journal of Pharmacology DA - 2009/11// PY - 2009 DO - 10.1111/j.1476-5381.2009.00503_6.x DP - PubMed Central VL - 158 IS - Suppl 1 SP - S130 EP - S134 J2 - Br J Pharmacol SN - 0007-1188 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2884561/ Y2 - 2018/10/27/02:52:18 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2884561/pdf/bph0158-S130.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2884561/ ER - TY - CHAP TI - Chapter 12 - The CLC Family of Chloride Channels and Transporters AU - Stauber, Tobias AU - Novarino, Gaia AU - Jentsch, Thomas J. T2 - Physiology and Pathology of Chloride Transporters and Channels in the Nervous System A2 - Alvarez-Leefmans, F. Javier A2 - Delpire, Eric AB - This chapter deals with the CLC family of chloride channels and transporters, which are expressed from bacteria to humans. This highly conserved family comprises nine members in mammals, which were identified by homology cloning subsequent to the family's founding member ClC-0 from Torpedo marmorata. According to their sequence homologies, they can be grouped into three subfamilies. All members of the first subfamily, ClC-1, -2, -Ka and –Kb are shown to reside in the plasma membrane and function as Clˉ channels that mediate, e.g. transepithelial Clˉ transport or are involved in stabilizing the resting potential of the plasma membrane. CLC proteins form rhombus-like dimers of two-fold symmetry and function mostly as homodimers. A CLC dimer works as a “double-barreled” translocation pathway in which each subunit provides its own pore. The independent operation of the two ion translocation pathways was deduced first from the analysis of the reconstituted Torpedo channel. CY - San Diego DA - 2010/01/01/ PY - 2010 DP - ScienceDirect SP - 209 EP - 231 PB - Academic Press SN - 978-0-12-374373-2 UR - http://www.sciencedirect.com/science/article/pii/B9780123743732000121 Y2 - 2018/10/27/02:29:02 L2 - https://www.sciencedirect.com/science/article/pii/B9780123743732000121 ER - TY - JOUR TI - Corneal endothelial morphology and central thickness in patients with type II diabetes mellitus AU - Storr-Paulsen, Allan AU - Singh, Amardeep AU - Jeppesen, Helene AU - Norregaard, Jens C. AU - Thulesen, Jesper T2 - Acta Ophthalmologica DA - 2014/03// PY - 2014 DO - 10.1111/aos.12064 DP - Crossref VL - 92 IS - 2 SP - 158 EP - 160 LA - en SN - 1755375X UR - http://doi.wiley.com/10.1111/aos.12064 Y2 - 2018/10/22/21:33:23 ER - TY - JOUR TI - The Role of Transient Receptor Potential Cation Channels in Ca2+ Signaling AU - Gees, Maarten AU - Colsoul, Barbara AU - Nilius, Bernd T2 - Cold Spring Harbor Perspectives in Biology AB - The 28 mammalian members of the super-family of transient receptor potential (TRP) channels are cation channels, mostly permeable to both monovalent and divalent cations, and can be subdivided into six main subfamilies: the TRPC (canonical), TRPV (vanilloid), TRPM (melastatin), TRPP (polycystin), TRPML (mucolipin), and the TRPA (ankyrin) groups. TRP channels are widely expressed in a large number of different tissues and cell types, and their biological roles appear to be equally diverse. In general, considered as polymodal cell sensors, they play a much more diverse role than anticipated. Functionally, TRP channels, when activated, cause cell depolarization, which may trigger a plethora of voltage-dependent ion channels. Upon stimulation, Ca2+ permeable TRP channels generate changes in the intracellular Ca2+ concentration, [Ca2+]i, by Ca2+ entry via the plasma membrane. However, more and more evidence is arising that TRP channels are also located in intracellular organelles and serve as intracellular Ca2+ release channels. This review focuses on three major tasks of TRP channels: (1) the function of TRP channels as Ca2+ entry channels; (2) the electrogenic actions of TRPs; and (3) TRPs as Ca2+ release channels in intracellular organelles., TRP channels in the plasma membrane allow calcium into cells, causing depolarization and activation of voltage-dependent ion channels. They also exist on organelles and may function as scaffolds for signaling complexes. DA - 2010/10// PY - 2010 DO - 10.1101/cshperspect.a003962 DP - PubMed Central VL - 2 IS - 10 J2 - Cold Spring Harb Perspect Biol SN - 1943-0264 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2944357/ Y2 - 2018/10/18/22:04:51 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2944357/pdf/cshperspect-CAL-a003962.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2944357/ ER - TY - JOUR TI - Temperature-Sensitive Transient Receptor Potential Channels in Corneal Tissue Layers and Cells AU - Mergler, Stefan AU - Valtink, Monika AU - Takayoshi, Sumioka AU - Okada, Yuka AU - Miyajima, Masayasu AU - Saika, Shizuya AU - Reinach, Peter S. T2 - Ophthalmic Research AB - We here provide a brief summary of the characteristics of transient receptor potential channels (TRPs) identified in corneal tissue layers and cells. In general, TRPs are nonselective cation channels which are Ca2+ permeable. Most TRPs serve as thermosensitive molecular sensors (thermo-TRPs). Based on their functional importance, the possibilities are described for drug-targeting TRP activity in a clinical setting. TRPs are expressed in various tissues of the eye including both human corneal epithelial and endothelial layers as well as stromal fibroblasts and stromal nerve fibers. TRP vanilloid type 1 (TRPV1) heat receptor, also known as capsaicin receptor, along with TRP melastatin type 8 (TRPM8) cold receptor, which is also known as menthol receptor, are prototypes of the thermo-TRP family. The TRPV1 functional channel is the most investigated TRP channel in these tissues, owing to its contribution to maintaining tissue homeostasis as well as eliciting wound healing responses to injury. Other thermo-TRP family members identified in these tissues are TRPV2, 3 and 4. Finally, there is the TRP ankyrin type 1 (TRPA1) cold receptor. All of these thermo-TRPs can be activated within specific temperature ranges and transduce such inputs into chemical and electrical signals. Although several recent studies have begun to unravel complex roles for thermo-TRPs such as TRPV1 in corneal layers and resident cells, additional studies are needed to further elucidate their roles in health and disease. DA - 2014/// PY - 2014 DO - 10.1159/000365334 DP - www.karger.com VL - 52 IS - 3 SP - 151 EP - 159 J2 - ORE LA - english SN - 0030-3747, 1423-0259 UR - https://www.karger.com/Article/FullText/365334 Y2 - 2018/10/18/21:25:33 L1 - https://www.karger.com/Article/Pdf/365334 L2 - http://www.ncbi.nlm.nih.gov/pubmed/25301091 L2 - https://www.karger.com/Article/FullText/365334#ref23 ER - TY - JOUR TI - ORAI channels are critical for receptor-mediated endocytosis of albumin AU - Zeng, Bo AU - Chen, Gui-Lan AU - Garcia-Vaz, Eliana AU - Bhandari, Sunil AU - Daskoulidou, Nikoleta AU - Berglund, Lisa M. AU - Jiang, Hongni AU - Hallett, Thomas AU - Zhou, Lu-Ping AU - Huang, Li AU - Xu, Zi-Hao AU - Nair, Viji AU - Nelson, Robert G. AU - Ju, Wenjun AU - Kretzler, Matthias AU - Atkin, Stephen L. AU - Gomez, Maria F. AU - Xu, Shang-Zhong T2 - Nature Communications AB - Patients with diabetic nephropathy suffer from impaired albumin reabsorption by proximal tubular epithelial cells. Here authors use diabetic and transgenic mouse models and in vitro models to show the cause for this lies in the down regulation and internalization of the ion channels, ORAI1-3. DA - 2017/12/04/ PY - 2017 DO - 10.1038/s41467-017-02094-y DP - www.nature.com VL - 8 IS - 1 SP - 1920 LA - en SN - 2041-1723 UR - https://www.nature.com/articles/s41467-017-02094-y Y2 - 2018/10/18/21:00:17 L1 - https://www.nature.com/articles/s41467-017-02094-y.pdf L2 - https://www.nature.com/articles/s41467-017-02094-y ER - TY - JOUR TI - New Insights Into Electrophysiology and Functional Transient Receptor Potential (Trp) Channel Expression in the Corneal Endothelium AU - Mergler, S. AU - Valtink, M. AU - Engelmann, K. AU - Pleyer, U. T2 - Investigative Ophthalmology & Visual Science DA - 2008/05/14/ PY - 2008 DP - iovs.arvojournals.org VL - 49 IS - 13 SP - 3939 EP - 3939 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - https://iovs.arvojournals.org/article.aspx?articleid=2379333 Y2 - 2018/10/18/19:58:56 L2 - https://iovs.arvojournals.org/article.aspx?articleid=2379333 ER - TY - JOUR TI - TRPV channels mediate temperature-sensing in human corneal endothelial cells AU - Mergler, Stefan AU - Valtink, Monika AU - Coulson-Thomas, Vivien Jane AU - Lindemann, Dirk AU - Reinach, Peter S. AU - Engelmann, Katrin AU - Pleyer, Uwe T2 - Experimental Eye Research AB - The physiology and transparency of the cornea are dependent on corneal endothelial function. The role of temperature sensitive ion channels in maintaining such activity is unknown. This study was undertaken to probe for the functional expression of such pathways in human corneal endothelial cells (HCEC). We used HCEC-12, an immortalized population derived from whole corneal endothelium, and two morphologically distinct clonal cell lines derived from HCEC-12 (HCEC-H9C1, HCEC-B4G12) to probe for gene expression and function of transient receptor potential (TRP) channels of the vanilloid (V) isoform subfamily (i.e. TRPV1-3) in these cell types. Expression of TRPV isotypes 1, 2 and 3 were detected by RT-PCR. Protein expression of TRPV1 in situ was confirmed by immunostaining of corneoscleral remnants after keratoplasty. TRPV1-3 functional activity was evident based on capsaicin-induced Ca(2+) transients and induction of these responses through rises in ambient temperature from 25 degrees C to over 40 degrees C. The currents underlying Ca(2+) transients were characterized with a novel high throughput patch-clamp system. The TRPV1 selective agonist, capsaicin (CAP) (10-20 microM) increased non-selective cation whole-cell currents resulting in calcium increases that were fully blocked by either the TRPV1 antagonist capsazepine (CPZ) or removal of extracellular calcium. Similarly, heating from room temperature to over 40 degrees C increased the same currents resulting in calcium increases that were significantly reduced by the TRP channel blockers lanthanum chloride (La(3+)) (100 microM) and ruthenium-red (RuR) (10 microM), respectively. Moreover, application of the TRPV channel opener 2-aminoethoxydiphenyl borate (2-APB) (400 microM) led to a reversible increase in intracellular Ca(2+) indicating putative TRPV1-3 channel activity. Taken together, TRPV activity modulation by temperature underlies essential homeostatic mechanisms contributing to the support of corneal endothelial function under different ambient conditions. DA - 2010/06// PY - 2010 DO - 10.1016/j.exer.2010.03.010 DP - PubMed VL - 90 IS - 6 SP - 758 EP - 770 J2 - Exp. Eye Res. LA - eng SN - 1096-0007 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20338165 KW - Calcium KW - Cell Culture Techniques KW - Endothelium, Corneal KW - Gene Expression Regulation KW - Homeostasis KW - Hot Temperature KW - Humans KW - Immunoenzyme Techniques KW - Patch-Clamp Techniques KW - Reverse Transcriptase Polymerase Chain Reaction KW - Thermosensing KW - TRPV Cation Channels ER - TY - JOUR TI - Cellular and extracellular matrix modulation of corneal stromal opacity AU - Torricelli, Andre A. M. AU - Wilson, Steven E. T2 - Experimental eye research AB - Stromal transparency is a critical factor contributing to normal function of the visual system. Corneal injury, surgery, disease and infection elicit complex wound healing responses that serve to protect against insults and maintain the integrity of the cornea, and subsequently to restore corneal structure and transparency. However, in some cases these processes result in prolonged loss of corneal transparency and resulting diminished vision. Corneal opacity is mediated by the complex actions of many cytokines, growth factors, and chemokines produced by the epithelial cells, stromal cells, bone marrow-derived cells, lacrimal tissues, and nerves. Myofibroblasts, and the disorganized extracellular matrix produced by these cells, are critical determinants of the level and persistence of stromal opacity after corneal injury. Decreases in corneal crystallins in myofibroblasts and corneal fibroblasts contribute to cellular opacity in the stroma. Regeneration of a fully functional epithelial basement membrane (BM) appears to have a critical role in the maintenance of corneal stromal transparency after mild injuries and recovery of transparency when opacity is generated after severe injuries. The epithelial BM likely has a regulatory function whereby it modulates epithelium-derived growth factors such as transforming growth factor (TGF) β and platelet-derived growth factor (PDGF) that drive the development and persistence of myofibroblasts from precursor cells. The purpose of this article is to review the factors involved in the maintenance of corneal transparency and to highlight the mechanisms involved in the appearance, persistency and regression of corneal opacity after stromal injury. DA - 2014/12// PY - 2014 DO - 10.1016/j.exer.2014.09.013 DP - PubMed Central VL - 0 SP - 151 EP - 160 J2 - Exp Eye Res SN - 0014-4835 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4259857/ Y2 - 2018/10/17/02:30:12 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4259857/pdf/nihms635637.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4259857/ ER - TY - JOUR TI - Menthol Activation of Corneal Cool Cells Induces TRPM8-Mediated Lacrimation but Not Nociceptive Responses in Rodents AU - Robbins, Ashlee AU - Kurose, Masayuki AU - Winterson, Barbara J. AU - Meng, Ian D. T2 - Investigative Ophthalmology & Visual Science AB - Abstract Purpose.: Stimulation to the cornea via noxious chemical and mechanical means evokes tearing, blinking, and pain. In contrast, mild cooling of the ocular surface has been reported to increase lacrimation via activation of corneal cool primary afferent neurons. The purpose of our study was to determine whether menthol induces corneal cool cell activity and lacrimation via the transient receptor potential melastatin-8 (TRPM8) channel without evoking nociceptive responses. Methods.: Tear measurements were made using a cotton thread in TRPM8 wild type and knockout mice after application of menthol (0.05–50 mM) to the cornea. In additional studies, nocifensive responses (eye swiping and lid closure) were quantified following cornea menthol application. Trigeminal ganglion electrophysiologic single unit recordings were performed in rats to determine the effect of low and high concentrations of menthol on corneal cool cells. Results.: At low concentrations, menthol increased tear production in TRPM8 wild type and heterozygous animals, but had no effect in TRPM8 knockout mice, while nocifensive responses remained unaffected. At the highest concentration, menthol (50 mM) increased tearing and nocifensive responses in TRPM8 wild type and knockout animals. A low concentration of menthol (0.1 mM) increased cool cell activity, yet a high concentration of menthol (50 mM) had no effect. Conclusions.: These studies indicated that low concentrations of menthol can increase lacrimation via TRPM8 channels without evoking nocifensive behaviors. At high concentrations, menthol can induce lacrimation and nocifensive behaviors in a TRPM8 independent mechanism. The increase in lacrimation is likely due to an increase in cool cell activity. DA - 2012/10/09/ PY - 2012 DO - 10.1167/iovs.12-10025 VL - 53 IS - 11 SP - 7034 EP - 7042 J2 - Investigative Ophthalmology & Visual Science SN - 1552-5783 UR - http://dx.doi.org/10.1167/iovs.12-10025 N1 -

10.1167/iovs.12-10025

ER - TY - JOUR TI - The DAVID Gene Functional Classification Tool: a novel biological module-centric algorithm to functionally analyze large gene lists AU - Huang, Da Wei AU - Sherman, Brad T AU - Tan, Qina AU - Collins, Jack R AU - Alvord, W Gregory AU - Roayaei, Jean AU - Stephens, Robert AU - Baseler, Michael W AU - Lane, H Clifford AU - Lempicki, Richard A T2 - Genome Biology AB - The DAVID gene functional classification tool uses a novel fuzzy clustering algorithm to condense a list of genes or associated biological terms into organized classes of related genes or biology, called biological modules., The DAVID Gene Functional Classification Tool uses a novel agglomeration algorithm to condense a list of genes or associated biological terms into organized classes of related genes or biology, called biological modules. This organization is accomplished by mining the complex biological co-occurrences found in multiple sources of functional annotation. It is a powerful method to group functionally related genes and terms into a manageable number of biological modules for efficient interpretation of gene lists in a network context. DA - 2007/// PY - 2007 DO - 10.1186/gb-2007-8-9-r183 DP - PubMed Central VL - 8 IS - 9 SP - R183 J2 - Genome Biol SN - 1465-6906 ST - The DAVID Gene Functional Classification Tool UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2375021/ Y2 - 2018/09/25/06:30:44 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2375021/pdf/gb-2007-8-9-r183.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2375021/ ER - TY - JOUR TI - Methods that remove batch effects while retaining group differences may lead to exaggerated confidence in downstream analyses AU - Nygaard, Vegard AU - Rødland, Einar Andreas AU - Hovig, Eivind T2 - Biostatistics (Oxford, England) AB - Removal of, or adjustment for, batch effects or center differences is generally required when such effects are present in data. In particular, when preparing microarray gene expression data from multiple cohorts, array platforms, or batches for later analyses, batch effects can have confounding effects, inducing spurious differences between study groups. Many methods and tools exist for removing batch effects from data. However, when study groups are not evenly distributed across batches, actual group differences may induce apparent batch differences, in which case batch adjustments may bias, usually deflate, group differences. Some tools therefore have the option of preserving the difference between study groups, e.g. using a two-way ANOVA model to simultaneously estimate both group and batch effects. Unfortunately, this approach may systematically induce incorrect group differences in downstream analyses when groups are distributed between the batches in an unbalanced manner. The scientific community seems to be largely unaware of how this approach may lead to false discoveries. DA - 2016/01// PY - 2016 DO - 10.1093/biostatistics/kxv027 DP - PubMed Central VL - 17 IS - 1 SP - 29 EP - 39 J2 - Biostatistics SN - 1465-4644 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4679072/ Y2 - 2018/09/25/06:25:12 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4679072/pdf/kxv027.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4679072/ ER - TY - JOUR TI - Electron Microscopic Studies on Fuchs' Combined Dystrophy : I. Posterior Portion of the Cornea AU - Iwamoto, Takeo AU - Devoe, A. Gerard T2 - Investigative Ophthalmology & Visual Science DA - 1971/01/01/ PY - 1971 DP - iovs.arvojournals.org VL - 10 IS - 1 SP - 9 EP - 28 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 ST - Electron Microscopic Studies on Fuchs' Combined Dystrophy UR - https://iovs.arvojournals.org/article.aspx?articleid=2158325 Y2 - 2018/09/25/01:38:10 L1 - https://iovs.arvojournals.org/data/journals/iovs/933703/9.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2158325 ER - TY - JOUR TI - Corneal Endothelial Cell Proliferation: A Function of Cell Density AU - Patel, Sangita P. AU - Bourne, William M. T2 - Investigative ophthalmology & visual science AB - PURPOSE To determine how stimuli that increase corneal endothelial cell proliferation of human corneas in culture relate to changes in endothelial cell density in the central and peripheral cornea. METHODS Human donor cadaver corneas not suitable for transplantation were divided into four pie-shaped wedges and incubated at 37°C in medium supplemented with fetal bovine serum, epidermal growth factor, fibroblast growth factor, and gentamicin. To promote a proliferative response, samples were treated with EDTA at concentrations of 0, 0.5, 2.5, and 5.0 mM for 1 hour and then returned to culture medium. Endothelial cell proliferation was assayed with Ki-67 immunolocalization 48 and 96 hours after EDTA treatment. Samples were mounted with propidium iodide or DAPI. The total number of cells and the number of Ki-67–positive cells were counted in three regions, defined as central, mid, and peripheral cornea, to determine endothelial cell density and percentage of proliferation. RESULTS A proliferative response to EDTA was not found. However, increased proliferation was noted in the central compared with the peripheral corneal region. Unexpectedly, the increased proliferation in the central region corresponded to a trend of lower endothelial cell density in the central region compared with the peripheral region. Corneal endothelial cell proliferation under our culture conditions is noted primarily when cell density is less than 2000 cells/mm2. CONCLUSIONS Corneal endothelial cell proliferation under our culture conditions does not lead to supranormal endothelial cell density. Rather, cell proliferation is noted in those regions that may be experiencing a greater burden of cell loss. DA - 2009/06// PY - 2009 DO - 10.1167/iovs.08-3002 DP - PubMed Central VL - 50 IS - 6 SP - 2742 EP - 2746 J2 - Invest Ophthalmol Vis Sci SN - 0146-0404 ST - Corneal Endothelial Cell Proliferation UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2728347/ Y2 - 2018/08/28/20:52:19 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2728347/pdf/nihms134907.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2728347/ ER - TY - ELEC TI - Corneal Endothelial Cell Proliferation: A Function of Cell Density UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2728347/ Y2 - 2018/08/28/20:51:09 L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2728347/ ER - TY - JOUR TI - Proliferative capacity of the corneal endothelium AU - Joyce, Nancy C. T2 - Progress in Retinal and Eye Research AB - Corneal endothelium is the single layer of cells forming a boundary between the corneal stroma and anterior chamber. The barrier and "pump" functions of the endothelium are responsible for maintaining corneal transparency by regulating stromal hydration. Morphological studies have demonstrated an age-related decrease in endothelial cell density and indicate that the endothelium in vivo either does not proliferate at all or proliferates at a rate that does not keep pace with the rate of cell loss. Lack of a robust proliferative response to cell loss makes the endothelium, at best, a fragile tissue. As a result of excessive cell loss due to accidental or surgical trauma, dystrophy, or disease, the endothelium may no longer effectively act as a barrier to fluid flow from the aqueous humor to the stroma. This loss of function can cause corneal edema, decreased corneal clarity, and loss of visual acuity, thus requiring corneal transplantation to restore normal vision. Studies from this and other laboratories indicate that corneal endothelium in vivo DOES possess proliferative capacity, but is arrested in G1-phase of the cell cycle. It appears that several intrinsic and extrinsic factors together contribute to maintain the endothelium in a non-replicative state. Ex vivo studies comparing cell cycle kinetics in wounded endothelium of young (< 30 years old) and older donors ( > 50 years old) provide evidence that cells from older donors can enter and complete the cell cycle; however, the length of G1-phase appears to be longer and the cells require stronger mitogenic stimulation than cells from younger donors. In vivo conditions per se also contribute to maintenance of a non-replicative monolayer. Endothelial cells are apparently unable to respond to autocrine or paracrine stimulation even though they express mRNA and protein for a number of growth factors and their receptors. Exogenous transforming growth factor-beta (TGF-beta) and TGF-beta in aqueous humor suppress S-phase entry in cultured endothelial cells, suggesting that this cytokine could inhibit proliferation in vivo. In addition, cell-cell contact appears to inhibit endothelial cell proliferation during corneal development and to help maintain the mature endothelial monolayer in a non-proliferative state, in part, via the activity of p27kip1, a known G1-phase inhibitor. The fact that human corneal endothelium retains proliferative capacity has led to recent efforts to induce division and increase the density of these important cells. For example, recent studies have demonstrated that adult human corneal endothelial cells can be induced to grow in culture and then transplanted to recipient corneas ex vivo. The laboratory work that has been conducted up to now opens an exciting new door to the future. The time is right to apply the knowledge that has been gained regarding corneal endothelial cell proliferative capacity and regulation of its cell cycle to develop new therapies to treat patients at risk for vision loss due to low endothelial cells counts. DA - 2003/05// PY - 2003 DP - PubMed VL - 22 IS - 3 SP - 359 EP - 389 J2 - Prog Retin Eye Res LA - eng SN - 1350-9462 L2 - http://www.ncbi.nlm.nih.gov/pubmed/12852491 KW - Animals KW - Cell Communication KW - Cell Cycle KW - Cell Division KW - Cells, Cultured KW - Cellular Senescence KW - Endothelium, Corneal KW - Humans KW - Transplantation ER - TY - JOUR TI - Thermosensitive transient receptor potential channels (thermo-TRPs) in human corneal epithelial cells AU - Mergler, Stefan AU - Garreis, Fabian AU - Sahlmüller, Monika AU - Reinach, Peter S. AU - Paulsen, Friedrich AU - Pleyer, Uwe T2 - Journal of Cellular Physiology AB - Thermosensitive transient receptor potential proteins (TRPs) such as TRPV1-TRPV4 are all heat-activated non-selective cation channels that are modestly permeable to Ca2+. TRPV1, TRPV3 and TRPV4 functional expression were previously identified in human corneal epithelial cells (HCEC). However, the membrane currents were not described underlying their activation by either selective agonists or thermal variation. This study characterized the membrane currents and [Ca 2+]i transients induced by thermal and agonist TRPV1 and 4 stimulation. TRPV1 and 4 expressions were confirmed by RT-PCR and TRPV2 transcripts were also detected. In fura2-loaded HCEC, a TRPV1-3 selective agonist, 100 µM 2-aminoethoxydiphenyl borate (2-APB), induced intracellular Ca2+ transients and an increase in non-selective cation outward currents that were suppressed by ruthenium-red (RuR) (10–20 µM), a nonselective TRPV channel blocker. These changes were also elicited by rises in ambient temperature from 25 °C to over 40 °C. RuR (5 µM) and a selective TRPV1 channel blocker capsazepine (CPZ) (10 µM) or another related blocker, lanthanum chloride (La3+) (100 µM) suppressed these temperature-induced Ca2+ increases. Planar patch-clamp technique was used to characterize the currents underlying Ca2+ transients. Increasing the temperature to over 40 °C induced reversible rises in non-selective cation currents. Moreover, a hypotonic challenge (25 %) increased non-selective cation currents confirming TRPV4 activity. We conclude that HCEC possess in addition to thermo-sensitive TRPV3 activity TRPV1, TRPV2 and TRPV4 activity. Their activation confers temperature sensitivity at the ocular surface, which may protect the cornea against such stress. DA - 2011/07// PY - 2011 DO - 10.1002/jcp.22514 DP - PubMed Central VL - 226 IS - 7 SP - 1828 EP - 1842 J2 - J Cell Physiol SN - 0021-9541 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3072442/ Y2 - 2018/07/17/02:41:58 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3072442/pdf/nihms258180.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3072442/ ER - TY - JOUR TI - Ocular transient receptor potential channel function in health and disease AU - Reinach, Peter S. AU - Mergler, Stefan AU - Okada, Yuka AU - Saika, Shizuya T2 - BMC Ophthalmology AB - Transient receptor potential (TRP) channels sense and transduce environmental stimuli into Ca2+ transients that in turn induce responses essential for cell function and adaptation. These non-selective channels with variable Ca2+ selectivity are grouped into seven different subfamilies containing 28 subtypes based on differences in amino acid sequence homology. Many of these subtypes are expressed in the eye on both neuronal and non-neuronal cells where they affect a host of stress-induced regulatory responses essential for normal vision maintenance. This article reviews our current knowledge about the expression, function and regulation of TRPs in different eye tissues. We also describe how under certain conditions TRP activation can induce responses that are maladaptive to ocular function. Furthermore, the possibility of an association between TRP mutations and disease is considered. These findings contribute to evidence suggesting that drug targeting TRP channels may be of therapeutic benefit in a clinical setting. We point out issues that must be more extensively addressed before it will be possible to decide with certainty that this is a realistic endeavor. Another possible upshot of future studies is that disease process progression can be better evaluated by profiling changes in tissue specific functional TRP subtype activity as well as their gene and protein expression. DA - 2015/12/17/ PY - 2015 DO - 10.1186/s12886-015-0135-7 DP - BioMed Central VL - 15 IS - 1 SP - 153 J2 - BMC Ophthalmology SN - 1471-2415 UR - https://doi.org/10.1186/s12886-015-0135-7 Y2 - 2018/07/16/18:30:34 L1 - https://bmcophthalmol.biomedcentral.com/track/pdf/10.1186/s12886-015-0135-7 L2 - https://bmcophthalmol.biomedcentral.com/articles/10.1186/s12886-015-0135-7 KW - Calcium KW - Cornea KW - Lens KW - Retina KW - Transient receptor potential ion channels KW - Uvea ER - TY - JOUR TI - TRP Channels AU - Venkatachalam, Kartik AU - Montell, Craig T2 - Annual review of biochemistry AB - The TRP (Transient Receptor Potential) superfamily of cation channels is remarkable in that it displays greater diversity in activation mechanisms and selectivities than any other group of ion channels. The domain organizations of some TRP proteins are also unusual, as they consist of linked channel and enzyme domains. A unifying theme in this group is that TRP proteins play critical roles in sensory physiology, which include contributions to vision, taste, olfaction, hearing, touch, and thermo- and osmosensation. In addition, TRP channels enable individual cells to sense changes in their local environment. Many TRP channels are activated by a variety of different stimuli and function as signal integrators. The TRP superfamily is divided into seven subfamilies: the five group 1 TRPs (TRPC, TRPV, TRPM, TRPN, and TRPA) and two group 2 subfamilies (TRPP and TRPML). TRP channels are important for human health as mutations in at least four TRP channels underlie disease. DA - 2007/// PY - 2007 DO - 10.1146/annurev.biochem.75.103004.142819 DP - PubMed Central VL - 76 SP - 387 EP - 417 J2 - Annu Rev Biochem SN - 0066-4154 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4196875/ Y2 - 2018/07/16/16:27:34 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4196875/pdf/nihms273468.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4196875/ ER - TY - ELEC TI - TRP Channels | Annual Review of Biochemistry UR - https://www.annualreviews.org/doi/abs/10.1146/annurev.biochem.75.103004.142819?rfr_dat=cr_pub%3Dpubmed&url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&journalCode=biochem Y2 - 2018/07/16/16:25:31 L2 - https://www.annualreviews.org/doi/abs/10.1146/annurev.biochem.75.103004.142819?rfr_dat=cr_pub%3Dpubmed&url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&journalCode=biochem ER - TY - JOUR TI - Molecular modulators of store-operated calcium entry AU - Lopez, Jose J. AU - Albarran, Letizia AU - Gómez, Luis J. AU - Smani, Tarik AU - Salido, Gines M. AU - Rosado, Juan A. T2 - Biochimica et Biophysica Acta (BBA) - Molecular Cell Research AB - Three decades ago, store-operated Ca2+ entry (SOCE) was identified as a unique mechanism for Ca2+ entry through plasma membrane (PM) Ca2+-permeable channels modulated by the intracellular Ca2+ stores, mainly the endoplasmic reticulum (ER). Extensive analysis of the communication between the ER and the PM leads to the identification of the protein STIM1 as the ER-Ca2+ sensor that gates the Ca2+ channels in the PM. Further analysis on the biophysical, electrophysiological and biochemical properties of STIM1-dependent Ca2+ channels has revealed the presence of a highly Ca2+-selective channel termed Ca2+ release-activated Ca2+ channel (CRAC), consisting of Orai1 subunits, and non-selective cation channels named store-operated channels (SOC), including both Orai1 and TRPC channel subunits. Since the identification of the key elements of CRAC and SOC channels a number of intracellular modulators have been reported to play essential roles in the stabilization of STIM–Orai interactions, collaboration with STIM1 conformational changes or mediating slow Ca2+-dependent inactivation. Here, we review our current understanding of some of the key modulators of STIM1–Orai1 interaction, including the proteins CRACR2A, STIMATE, SARAF, septins, golli and ORMDL3. DA - 2016/08/01/ PY - 2016 DO - 10.1016/j.bbamcr.2016.04.024 DP - ScienceDirect VL - 1863 IS - 8 SP - 2037 EP - 2043 J2 - Biochimica et Biophysica Acta (BBA) - Molecular Cell Research SN - 0167-4889 UR - http://www.sciencedirect.com/science/article/pii/S0167488916301240 Y2 - 2018/06/06/13:40:06 L1 - https://ac.els-cdn.com/S0167488916301240/1-s2.0-S0167488916301240-main.pdf?_tid=d6295360-b45e-47a1-8268-35ca099ba58e&acdnat=1528292586_01d98da123d5209eb22fcb8c2ef98eb0 L2 - https://www.sciencedirect.com/science/article/pii/S0167488916301240 KW - CRACR2A KW - Golli KW - Orai1 KW - ORMDL3 KW - SARAF KW - Septin KW - STIM1 KW - Store-operated calcium entry ER - TY - JOUR TI - Molecular Bases of Corneal Endothelial Dystrophies AU - Schmedt, Thore AU - Silva, Mariana Mazzini AU - Ziaei, Alireza AU - Jurkunas, Ula T2 - Experimental Eye Research AB - The phrase “corneal endothelial dystrophies” embraces a group of bilateral corneal conditions that are characterized by a non-inflammatory and progressive degradation of corneal endothelium. Corneal endothelial cells exhibit a high pump site density and, along with barrier function, are responsible for maintaining the cornea in its natural state of relative dehydration. Gradual loss of endothelial cells leads to an insufficient water outflow, resulting in corneal edema and loss of vision. Since the pathologic mechanisms remain largely unknown, the only current treatment option is surgical transplantation when vision is severely impaired. In the past decade, important steps have been taken to understand how endothelial degeneration progresses on the molecular level. Studies of affected multigenerational families and sporadic cases identified genes and chromosomal loci, and revealed either Mendelian or complex disorder inheritance patterns. Mutations have been detected in genes that carry important structural, metabolic, cytoprotective, and regulatory functions in corneal endothelium. In addition to genetic predisposition, environmental factors like oxidative stress were found to be involved in the pathogenesis of endotheliopathies. This review summarizes and crosslinks the recent progress on deciphering the molecular bases of corneal endothelial dystrophies. DA - 2012/02// PY - 2012 DO - 10.1016/j.exer.2011.08.002 DP - PubMed Central VL - 95 IS - 1 SP - 24 EP - 34 J2 - Exp Eye Res SN - 0014-4835 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3273549/ Y2 - 2018/06/06/13:01:52 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3273549/pdf/nihms322214.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3273549/ ER - TY - JOUR TI - The Functions of Store-operated Calcium Channels AU - Putney, James W. AU - Steinckwich-Besançon, Natacha AU - Numaga-Tomita, Takuro AU - Davis, Felicity M. AU - Desai, Pooja N. AU - D’Agostin, Diane M. AU - Wu, Shilan AU - Bird, Gary S. T2 - Biochimica et biophysica acta AB - Store-operated calcium channels provide calcium signals to the cytoplasm of a wide variety of cell types. The basic components of this signaling mechanism include a mechanism for discharging Ca2+ stores (commonly but not exclusively phospholipase C and inositol 1,4,5-trisphosphate), a sensor in the endoplasmic reticulum that also serves as an activator of the plasma membrane channel (STIM1 and STIM2), and the store-operated channel (Orai1, 2 or 3). The advent of mice genetically altered to reduce store-operated calcium entry globally or in specific cell types has provided important tools to understand the functions of these widely encountered channels in specific and clinically important physiological systems. This review briefly discusses the history and cellular properties of store-operated calcium channels, and summarizes selected studies of their physiological functions in specific physiological or pathological contexts. DA - 2017/06// PY - 2017 DO - 10.1016/j.bbamcr.2016.11.028 DP - PubMed Central VL - 1864 IS - 6 SP - 900 EP - 906 J2 - Biochim Biophys Acta SN - 0006-3002 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5420336/ Y2 - 2018/06/03/22:55:44 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5420336/pdf/nihms838505.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5420336/ ER - TY - JOUR TI - Characterization of transient receptor potential vanilloid channel 4 (TRPV4) in human corneal endothelial cells AU - Mergler, Stefan AU - Valtink, Monika AU - Taetz, Katrin AU - Sahlmüller, Monika AU - Fels, Gabriele AU - Reinach, Peter S. AU - Engelmann, Katrin AU - Pleyer, Uwe T2 - Experimental Eye Research AB - The transient receptor potential vanilloid 4 (TRPV4) is a Ca(2+)-and Mg(2+) permeable cation channel that might be a cellular osmosensor since it is activated upon hypotonic cell swelling. TRPV4 is also thermosensitive and responds to moderate heat (from 24 to 27 °C) as well as to phorbol esters (4α-PDD) and several endogenous substances including arachidonic acid (AA), the endocannabinoids anandamide and 2-AG, and cytochrome P-450 metabolites of AA, such as epoxyeicosatrienoic acids. The resulting Ca(2+) influx occurring in response to swelling induces regulatory volume decrease (RVD) behavior. As regulation of cell volume is essential for corneal endothelial function, we determined whether human corneal endothelial cells have functional TRPV4 channel activity. RT-PCR identified TRPV4 gene expression in the HCEC-12 cell line as well as two clonal daughter cell lines (HCEC-H9C1, HCEC-B4G12). [Ca(2+)](i) transients were monitored in fura-2 loaded cells. Nonselective cation channel currents were recorded in the whole-cell mode of the planar patch-clamp technique. TRPV4 mRNA was found in HCEC-12 and the clonal daughter cell lines. TRPV4 channel agonists (4α-PDD and GSK1016790A; both 5 μmol/l) as well as moderate heat (<40 °C) elicited [Ca(2+)](i) transients. Hypotonicity increased [Ca(2+)](i) and nonselective cation channel currents in HCEC-12 cells. There is functional TRPV4 expression in HCEC-12 and in its clonal daughter cell lines based on Ca(2+) transients and underlying currents induced by known activators of this channel. DA - 2011/11// PY - 2011 DO - 10.1016/j.exer.2011.09.021 DP - PubMed VL - 93 IS - 5 SP - 710 EP - 719 J2 - Exp. Eye Res. LA - eng SN - 1096-0007 L2 - http://www.ncbi.nlm.nih.gov/pubmed/21996372 L2 - http://www.ncbi.nlm.nih.gov/pubmed/21996372 KW - Calcium KW - Cell Line KW - Endothelium, Corneal KW - Fura-2 KW - Gene Expression Regulation KW - Hot Temperature KW - Humans KW - Leucine KW - Patch-Clamp Techniques KW - Phorbols KW - Real-Time Polymerase Chain Reaction KW - RNA, Messenger KW - Sulfonamides KW - TRPV Cation Channels ER - TY - JOUR TI - Store-Operated Calcium Channels AU - Prakriya, Murali AU - Lewis, Richard S. T2 - Physiological Reviews AB - Store-operated calcium channels (SOCs) are a major pathway for calcium signaling in virtually all metozoan cells and serve a wide variety of functions ranging from gene expression, motility, and secretion to tissue and organ development and the immune response. SOCs are activated by the depletion of Ca2+ from the endoplasmic reticulum (ER), triggered physiologically through stimulation of a diverse set of surface receptors. Over 15 years after the first characterization of SOCs through electrophysiology, the identification of the STIM proteins as ER Ca2+ sensors and the Orai proteins as store-operated channels has enabled rapid progress in understanding the unique mechanism of store-operate calcium entry (SOCE). Depletion of Ca2+ from the ER causes STIM to accumulate at ER-plasma membrane (PM) junctions where it traps and activates Orai channels diffusing in the closely apposed PM. Mutagenesis studies combined with recent structural insights about STIM and Orai proteins are now beginning to reveal the molecular underpinnings of these choreographic events. This review describes the major experimental advances underlying our current understanding of how ER Ca2+ depletion is coupled to the activation of SOCs. Particular emphasis is placed on the molecular mechanisms of STIM and Orai activation, Orai channel properties, modulation of STIM and Orai function, pharmacological inhibitors of SOCE, and the functions of STIM and Orai in physiology and disease. DA - 2015/09/23/ PY - 2015 DO - 10.1152/physrev.00020.2014 DP - physiology.org (Atypon) VL - 95 IS - 4 SP - 1383 EP - 1436 J2 - Physiological Reviews SN - 0031-9333 UR - https://www.physiology.org/doi/abs/10.1152/physrev.00020.2014 Y2 - 2018/06/03/22:36:14 L1 - https://www.physiology.org/doi/pdf/10.1152/physrev.00020.2014?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed L2 - https://www.physiology.org/doi/abs/10.1152/physrev.00020.2014?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed ER - TY - JOUR TI - Change of Cytosolic Ca2+ Mobility in Cultured Bovine Corneal Endothelial Cells by Endothelin-1 AU - Hong, Show-Jen AU - Wu, Kwou-Yeung AU - Wang, Hwei-Zu AU - Fong, Jim. C T2 - Journal of Ocular Pharmacology and Therapeutics AB - The effect of endothelin-1 (ET-1) on the intracellular free Ca2+ ([Ca2+]i) in cultured bovine corneal endothelial cells was studied after loading with fura-2-AM. In Ca2+-containing buffer and Ca2+-free buffer, ET-1 induced a significant rise in [Ca2+]i at concentrations from 10-9 to 10-7 M. In Ca2+-free buffer, pretreatment of the cells with ET-1 inhibited thapsigargin-induced [Ca2+]i increase and carbonylcyanide m-chlorophenylhydrazone (CCCP)-induced Ca2+ release by 99% and 62%, respectively. Pretreatment of the cells with thapsigargin or CCCP also inhibited ET-1-induced [Ca2+]i rise by 36% and 92%, respectively. In Ca2+-containing buffer, the ETA receptor antagonist (BQ123) and ETB receptor antagonist (BQ788) partially inhibited ET-1-induced [Ca2+]i by 92% and 98%, respectively. Nifedipine and La3+ also inhibited ET-1-induced [Ca2+]i increase by 26% and 91%, respectively. The intracellular calcium release caused by ET-1 was partially inhibited by phospholipase C inhibitor (U73122). After incubation of the cells with ET-1 in Ca2+-free buffer, the addition of 5 mM CaCl2 increased Ca2+ influx, implying that release of Ca2+ from internal stores caused by ET-1 further induced capacitative Ca2+ entry. These data suggest that ET-1-induced [Ca2+]i rise in bovine corneal endothelial cells are mediated by ETA receptor, ETB receptor, La3+-sensitive Ca2+ pump and L-type voltage-operated Ca2+ channel, leading to Ca2+ influx. ET-1 also increased the internal Ca2+ release from endoplasmic reticulum and mitochondria Ca2+ stores followed by capacitative Ca2+ entry. ET-1-induced intracellular Ca2+ release was modulated by phospholipase C-coupled events. DA - 2003/02/01/ PY - 2003 DO - 10.1089/108076803762718060 DP - liebertpub.com (Atypon) VL - 19 IS - 1 SP - 1 EP - 9 J2 - Journal of Ocular Pharmacology and Therapeutics SN - 1080-7683 UR - https://www.liebertpub.com/doi/abs/10.1089/108076803762718060 Y2 - 2018/06/03/02:56:10 L2 - https://www.liebertpub.com/doi/abs/10.1089/108076803762718060?journalCode=jop ER - TY - JOUR TI - Calcium influx induced by activation of receptor tyrosine kinases in SV40-transfected human corneal endothelial cells AU - Mergler, Stefan AU - Dannowski, Haike AU - Bednarz, Jürgen AU - Engelmann, Katrin AU - Hartmann, Christian AU - Pleyer, Uwe T2 - Experimental Eye Research AB - This study was undertaken to investigate electrophysiological properties of immortalized SV40-transfected human corneal endothelial cells (HCEC-SV40) combined with the analysis of intracellular Ca(2+) responses mediated by ligands for receptor tyrosine kinases (RTK). In addition, the effects of several tyrosine kinase inhibitors were tested on Ca(2+) inflow mediated by induction of capacitative calcium entry (CCE). Patch-clamp techniques and measurements of the intracellular free Ca(2+) ([Ca(2+)](i)) by fura-2 were performed using HCEC-SV40. Stimulation of fibroblast growth factor receptors (FGFR) (e.g. by basic-FGF) (10 ng ml(-1)) elicited activation of Ca(2+) permeable channels and a subsequent increase of cytosolic free Ca(2+) in HCEC-SV40. This effect could be disrupted by the L-type Ca(2+) channel blocker nifedipine (5 microM). In addition, nifedipine significantly reduced the magnitude of CCE. Inhibition of protein tyrosine kinases (PTKs) by genistein, lavendustin A, or tyrphostin 51 (all 5 microM) also led to a reduction of CCE in HCEC-SV40. This study demonstrates for the first time that L-type Ca(2+) channel activity in HCEC-SV40 is linked to the activity of FGF receptor tyrosine kinases. These data regarding Ca(2+) inflow through Ca(2+) channels could be useful for investigation of culture and vitality conditions of HCEC. DA - 2003/10// PY - 2003 DP - PubMed VL - 77 IS - 4 SP - 485 EP - 495 J2 - Exp. Eye Res. LA - eng SN - 0014-4835 L2 - http://www.ncbi.nlm.nih.gov/pubmed/12957147 KW - Calcium KW - Calcium Channels KW - Cells, Cultured KW - Cornea KW - Electric Capacitance KW - Endothelium KW - Fibroblast Growth Factor 1 KW - Fibroblast Growth Factor 2 KW - Humans KW - Protein-Tyrosine Kinases KW - Receptor Protein-Tyrosine Kinases KW - Simian virus 40 KW - Transfection ER - TY - JOUR TI - Corneal endothelial cells possess an elaborate multipolar shape to maximize the basolateral to apical membrane area AU - Harrison, Theresa A. AU - He, Zhiguo AU - Boggs, Kristin AU - Thuret, Gilles AU - Liu, Hong-Xiang AU - Defoe, Dennis M. T2 - Molecular Vision AB - Purpose The corneal endothelium is widely believed to consist of geometrically regular cells interconnected by junctional complexes. However, while en face visualization of the endothelial apical surface reveals characteristic polygonal borders, the overall form of the component cells has rarely been observed. Methods To visualize the shape of individual endothelial cells within the native monolayer, two independent Cre/LoxP-based cell labeling approaches were used. In the first, a P0-Cre mouse driver strain was bred to an R26-tdTomato reporter line to map neural crest–derived endothelial cells with cytosolic red fluorescent protein. In the second, HPRT-Cre induction of small numbers of green and red fluorescent protein–filled cells within a background of unlabeled cells was achieved using a dual-color reporter system, mosaic analysis with double markers (MADM). Selective imaging of the endothelial lateral membranes at different apicobasal levels was accomplished after staining with antibodies to ZO-1 and the neural cell adhesion molecule (NCAM). Results When viewed in their entirety in whole-mount preparations, fluorescent protein–filled cells appear star-shaped, extending multiple dendritic processes that radiate outward in the plane of the monolayer. Examination of rare cases where cells expressing different fluorescent proteins lie directly adjacent to one another reveals that these long processes undergo extensive interdigitation. The resulting overlap allows individual cells to extend over a greater area than if the cell boundaries were mutually exclusive. Anti-NCAM staining of these interlocking peripheral cell extensions reveals an elaborate system of lateral membrane folds that, when viewed in optical sections, increase in complexity from the apical to the basal pole. This not only produces a substantial increase in the basolateral, relative to the apical, membrane but also greatly extends the paracellular pathway as a highly convoluted space. Conclusions Our analysis indicates that, far from being simple polygonal prisms, endothelial cells possess an elaborate multipolar shape. Their unusual geometry may be essential for the endothelium to carry out its role as the principal regulator of corneal extracellular fluid flux, and thus ultimately of tissue clarity. DA - 2016/01/16/ PY - 2016 DP - PubMed Central VL - 22 SP - 31 EP - 39 J2 - Mol Vis SN - 1090-0535 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4814271/ Y2 - 2018/06/03/00:10:48 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4814271/pdf/mv-v22-31.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4814271/ ER - TY - BOOK TI - Current Opinions in the Kyoto Cornea Club: Proceedings of the First Annual Meeting of the Kyoto Cornea Club, Kyoto, Japan, December 1-2, 1995 AU - Meeting, Kyoto Cornea Club AB - Preface During the past two decades, a significant international research exchange has taken place in order to understand the pathobiology of corneal diseases, and to develop more sophisticated treatments. For this purpose, many Japanese cornea specialists have been abroad to the United States, the United Kingdom, etc., to perform collaborative works in basic and clinical cornea research. As a result, many original concepts and thoughts have been produced from Japan, and some of them are now accepted world wide. Further to promote the international exchange of current knowledge and research on corneas in both health and disease, the First Annual Meeting of the Kyoto Cornea Club was held in Kyoto City on December I and 2, 1995. The goal of this meeting was to provide each speaker's updated knowledge that would be of value to all active corneal researchers who are interested in 'state-of-the-art' information from Japan. To achieve this objective fully, 41 selected Japanese cornea specialists registered as active participants in this meeting. James D. Zieske, PhD, from Schepens Eye Research Institute and the Department of Ophthalmology at Harvard Medical School, Boston, MA, USA, and Tadatsugu Taniguchi, PhD, from the Department of Immunology, Faculty of Medicine, Tokyo University, Japan, participated as special guests at this meeting, and both gave plenary lectures. This volume was created to provide each speaker's current opinions on the subjects they presented at this meeting, and also to provide a scientific reference for cornea research. We hope that the first issue will serve as a useful source of current knowledge and insight on Japanese cornea research. We wish to thank all those whose administrative help and/or assistance has made this issue possible; Takakazu Morita of Santen Pharmaceutical Co. Ltd., Machiko Tsujino of PMSI Japan, Ltd., and Kugler Publications. Shigeru Kinoshita and Yuichi Ohashi DA - 1997/// PY - 1997 DP - Google Books SP - 108 LA - en PB - Kugler Publications SN - 978-90-6299-138-9 ST - Current Opinions in the Kyoto Cornea Club L2 - https://books.google.com.co/books?id=ltk-bGFCUywC KW - Medical / Ophthalmology ER - TY - JOUR TI - Selenium: its role as antioxidant in human health AU - Tinggi, Ujang T2 - Environmental Health and Preventive Medicine DA - 2008/03// PY - 2008 DO - 10.1007/s12199-007-0019-4 DP - Crossref VL - 13 IS - 2 SP - 102 EP - 108 LA - en SN - 1342-078X, 1347-4715 ST - Selenium UR - http://link.springer.com/10.1007/s12199-007-0019-4 Y2 - 2019/02/04/16:53:41 L1 - https://link.springer.com/content/pdf/10.1007%2Fs12199-007-0019-4.pdf ER - TY - JOUR TI - Oxidative Stress and the Homeodynamics of Iron Metabolism AU - Bresgen, Nikolaus AU - Eckl, Peter T2 - Biomolecules DA - 2015/05/11/ PY - 2015 DO - 10.3390/biom5020808 DP - Crossref VL - 5 IS - 2 SP - 808 EP - 847 LA - en SN - 2218-273X UR - http://www.mdpi.com/2218-273X/5/2/808 Y2 - 2019/02/04/16:50:26 L1 - https://www.mdpi.com/2218-273X/5/2/808/pdf ER - TY - JOUR TI - Treatment with the KCa3.1 inhibitor TRAM-34 during diabetic ketoacidosis reduces inflammatory changes in the brain: TRAM-34 reduces DKA-related brain inflammation AU - Glaser, Nicole AU - Little, Christopher AU - Lo, Weei AU - Cohen, Michael AU - Tancredi, Daniel AU - Wulff, Heike AU - O'Donnell, Martha T2 - Pediatric Diabetes DA - 2017/08// PY - 2017 DO - 10.1111/pedi.12396 DP - Crossref VL - 18 IS - 5 SP - 356 EP - 366 LA - en SN - 1399543X ST - Treatment with the KCa3.1 inhibitor TRAM-34 during diabetic ketoacidosis reduces inflammatory changes in the brain UR - http://doi.wiley.com/10.1111/pedi.12396 Y2 - 2019/02/01/17:22:20 ER - TY - JOUR TI - Role of the potassium channel KCa3.1 in diabetic nephropathy AU - Huang, Chunling AU - Pollock, Carol A. AU - Chen, Xin-Ming T2 - Clinical Science DA - 2014/10/01/ PY - 2014 DO - 10.1042/CS20140075 DP - Crossref VL - 127 IS - 7 SP - 423 EP - 433 LA - en SN - 0143-5221, 1470-8736 UR - http://clinsci.org/lookup/doi/10.1042/CS20140075 Y2 - 2019/02/01/17:01:29 ER - TY - JOUR TI - Role of transforming growth factor Beta in corneal function, biology and pathology AU - Tandon, A. AU - Tovey, J. C. K. AU - Sharma, A. AU - Gupta, R. AU - Mohan, R. R. T2 - Current Molecular Medicine AB - Transforming growth factor-beta (TGFbeta) is a pleiotropic multifunctional cytokine that regulates several essential cellular processes in many parts of the body including the cornea. Three isoforms of TGFbeta are known in mammals and the human cornea expresses all of them. TGFbeta1 has been shown to play a central role in scar formation in adult corneas whereas TGFbeta2 and TGFbeta3 have been implicated to play a critical role in corneal development and scarless wound healing during embryogenesis. The biological effects of TGFbeta in the cornea have been shown to follow Smad dependent as well as Smad-independent signaling pathways depending upon cellular responses and microenvironment. Corneal TGFbeta expression is necessary for maintaining corneal integrity and corneal wound healing. On the other hand, TGFbeta is perhaps the most important cytokine in the pathogenesis of fibrotic disease in the cornea. Although the transformation of keratocytes to myofibroblasts induced by TGFbeta is largely believed to cause corneal fibrosis or scarring, the precise molecular mechanism(s) involved in this process is still unknown. Currently no drugs are available to treat corneal scarring effectively without causing significant side effects. Many approaches to treat TGFbeta-mediated corneal scarring are under investigation. These include blocking of TGFbeta, TGFbeta receptor, TGFbeta function and/or TGFbeta maturation. Other strategies such as modulating keratocyte proliferation, apoptosis, transcription and DNA condensation are also being investigated. The potential of gene therapy to neutralize the pathologic effects of TGFbeta has also been demonstrated recently. DA - 2010/08// PY - 2010 DP - PubMed VL - 10 IS - 6 SP - 565 EP - 578 J2 - Curr. Mol. Med. LA - eng SN - 1875-5666 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20642439 KW - Animals KW - Cornea KW - Humans KW - Models, Biological KW - Signal Transduction KW - Transforming Growth Factor beta ER - TY - JOUR TI - Prevention of diabetic keratopathy AU - Kaji, Y. T2 - The British Journal of Ophthalmology DA - 2005/03// PY - 2005 DO - 10.1136/bjo.2004.055541 DP - PubMed VL - 89 IS - 3 SP - 254 EP - 255 J2 - Br J Ophthalmol LA - eng SN - 0007-1161 L1 - https://bjo.bmj.com/content/89/3/254.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/15722297 KW - Aldehyde Reductase KW - Animals KW - Basement Membrane KW - Corneal Ulcer KW - Diabetes Complications KW - Diabetes Mellitus KW - Epithelium, Corneal KW - Glycation End Products, Advanced KW - Humans ER - TY - JOUR TI - Diabetic kidney disease AU - Thomas, Merlin C. AU - Brownlee, Michael AU - Susztak, Katalin AU - Sharma, Kumar AU - Jandeleit-Dahm, Karin A. M. AU - Zoungas, Sophia AU - Rossing, Peter AU - Groop, Per-Henrik AU - Cooper, Mark E. T2 - Nature Reviews Disease Primers DA - 2015/07/30/ PY - 2015 DO - 10.1038/nrdp.2015.18 DP - Crossref SP - 15018 SN - 2056-676X UR - http://www.nature.com/articles/nrdp201518 Y2 - 2019/02/01/15:47:16 ER - TY - JOUR TI - Redox imbalance stress in diabetes mellitus: Role of the polyol pathway AU - Yan, Liang-Jun T2 - Animal Models and Experimental Medicine AB - In diabetes mellitus, the polyol pathway is highly active and consumes approximately 30% glucose in the body. This pathway contains 2 reactions catalyzed by aldose reductase (AR) and sorbitol dehydrogenase, respectively. AR reduces glucose to sorbitol at the expense of NADPH, while sorbitol dehydrogenase converts sorbitol to fructose at the expense of NAD+, leading to NADH production. Consumption of NADPH, accumulation of sorbitol, and generation of fructose and NADH have all been implicated in the pathogenesis of diabetes and its complications. In this review, the roles of this pathway in NADH/NAD+ redox imbalance stress and oxidative stress in diabetes are highlighted. A potential intervention using nicotinamide riboside to restore redox balance as an approach to fighting diabetes is also discussed. DA - 2018/03// PY - 2018 DO - 10.1002/ame2.12001 DP - PubMed VL - 1 IS - 1 SP - 7 EP - 13 J2 - Animal Model Exp Med LA - eng SN - 2576-2095 ST - Redox imbalance stress in diabetes mellitus L1 - https://onlinelibrary.wiley.com/doi/pdf/10.1002/ame2.12001 L2 - http://www.ncbi.nlm.nih.gov/pubmed/29863179 KW - diabetes mellitus KW - fructose KW - NADH/NAD+ KW - oxidative stress KW - polyol pathway KW - redox imbalance stress ER - TY - JOUR TI - Mechanisms of diabetic complications AU - Forbes, Josephine M. AU - Cooper, Mark E. T2 - Physiological Reviews AB - It is increasingly apparent that not only is a cure for the current worldwide diabetes epidemic required, but also for its major complications, affecting both small and large blood vessels. These complications occur in the majority of individuals with both type 1 and type 2 diabetes. Among the most prevalent microvascular complications are kidney disease, blindness, and amputations, with current therapies only slowing disease progression. Impaired kidney function, exhibited as a reduced glomerular filtration rate, is also a major risk factor for macrovascular complications, such as heart attacks and strokes. There have been a large number of new therapies tested in clinical trials for diabetic complications, with, in general, rather disappointing results. Indeed, it remains to be fully defined as to which pathways in diabetic complications are essentially protective rather than pathological, in terms of their effects on the underlying disease process. Furthermore, seemingly independent pathways are also showing significant interactions with each other to exacerbate pathology. Interestingly, some of these pathways may not only play key roles in complications but also in the development of diabetes per se. This review aims to comprehensively discuss the well validated, as well as putative mechanisms involved in the development of diabetic complications. In addition, new fields of research, which warrant further investigation as potential therapeutic targets of the future, will be highlighted. DA - 2013/01// PY - 2013 DO - 10.1152/physrev.00045.2011 DP - PubMed VL - 93 IS - 1 SP - 137 EP - 188 J2 - Physiol. Rev. LA - eng SN - 1522-1210 L2 - http://www.ncbi.nlm.nih.gov/pubmed/23303908 KW - Animals KW - Blood Glucose KW - Diabetes Complications KW - Diabetes Mellitus, Type 1 KW - Diabetes Mellitus, Type 2 KW - Diabetic Angiopathies KW - Diabetic Nephropathies KW - Diabetic Neuropathies KW - Disease Models, Animal KW - Gene Expression Regulation KW - Glycation End Products, Advanced KW - Humans KW - Inflammation Mediators KW - Oxidative Stress KW - Prognosis KW - Risk Factors KW - Signal Transduction ER - TY - JOUR TI - Extracellular Matrix and Integrin Expression Profiles in Fuchs Endothelial Corneal Dystrophy Cells and Tissue Model AU - Goyer, Benjamin AU - Thériault, Mathieu AU - Gendron, Sébastien P. AU - Brunette, Isabelle AU - Rochette, Patrick J. AU - Proulx, Stéphanie T2 - Tissue Engineering. Part A AB - Primary corneal endothelial cell (CEC) cultures and 3D-engineered tissue models were used to study the aberrant deposition of extracellular matrix (ECM) in a vision impairing pathology known as Fuchs endothelial corneal dystrophy (FECD). CECs were isolated from excised Descemet membranes of patients with end-stage FECD. CECs isolated from healthy corneas served as controls. Microarray gene profiling was performed on postconfluent cultures of healthy and FECD cells. Protein expression analyses were conducted on tissue models that were engineered by seeding an endothelium on previously devitalized human stromal carriers. The engineered endothelia were kept in culture for 1-3 weeks to reform the endothelial monolayer. Protein expression of integrin subunits α4, α6, αv, and β1, as well as laminin, type IV collagen, fibronectin, clusterin, and transforming growth factor β-induced protein (TGFβIp) was then assessed by immunofluorescence. Microarray analysis showed nonstatistical twofold downregulation of collagen-coding genes (COL4A4, COL8A2, and COL21A1) and a twofold upregulation of the COL6A1, laminin α3 gene LAMA3, and integrin subunit α10 gene ITGA10 in FECD cells. Fibronectin type III domain containing 4 (FNDC4) and integrin β5 (ITGB5) genes was significantly upregulated in FECD cells. Immunostainings demonstrated that the protein expression of the integrin subunits α4, α6, αv, and β1, type IV collagen, as well as laminin remained similar between native and engineered endothelia. TGFβIp expression was found on the stromal side of both FECD and healthy Descemet's membrane, and only one out of three FECD specimens was positive for the clusterin protein. Interestingly, the ECM protein fibronectin was also found to have a stronger presence on engineered FECD tissues, a result consistent with the native FECD specimens. To conclude, this study allowed to identify fibronectin deposition as one of the first steps in the pathogenesis of FECD, as defined by our engineered tissue model. This opens the way to an entirely new perspective for in vitro pharmacological testing of new therapies for FECD, the leading indication for corneal transplantation in North America. DA - 2018//04/ PY - 2018 DO - 10.1089/ten.TEA.2017.0128 DP - PubMed VL - 24 IS - 7-8 SP - 607 EP - 615 J2 - Tissue Eng Part A LA - eng SN - 1937-335X L1 - https://europepmc.org/articles/pmc5905948?pdf=render L2 - http://www.ncbi.nlm.nih.gov/pubmed/28726551 KW - Aged KW - Aged, 80 and over KW - cell culture KW - Cells, Cultured KW - Collagen Type IV KW - Collagen Type VI KW - Collagen Type VIII KW - corneal endothelium KW - Endothelium, Corneal KW - extracellular matrix KW - Extracellular Matrix KW - Extracellular Matrix Proteins KW - Female KW - fibronectin KW - Fibronectins KW - Fuchs corneal endothelial dystrophy KW - Fuchs' Endothelial Dystrophy KW - gene profiling KW - Humans KW - immunolocalization KW - Integrin beta Chains KW - integrins KW - Integrins KW - Male KW - Middle Aged KW - Proteins KW - tissue engineering ER - TY - JOUR TI - Involvement of ZEB1 and Snail1 in excessive production of extracellular matrix in Fuchs endothelial corneal dystrophy AU - Okumura, Naoki AU - Minamiyama, Ryuki AU - Ho, Leona Ty AU - Kay, EunDuck P. AU - Kawasaki, Satoshi AU - Tourtas, Theofilos AU - Schlötzer-Schrehardt, Ursula AU - Kruse, Friedrich E. AU - Young, Robert D. AU - Quantock, Andrew J. AU - Kinoshita, Shigeru AU - Koizumi, Noriko T2 - Laboratory Investigation; a Journal of Technical Methods and Pathology AB - Fuchs endothelial corneal dystrophy (FECD) due to corneal endothelial cell degeneration is a major cause of corneal transplantation. It is characterized by abnormal deposition of extracellular matrix (ECM), such as corneal guttae, accompanied by a loss of endothelial cells. Although recent studies have revealed several genomic factors, the molecular pathophysiology of FECD has not yet been revealed. In this study, we establish a cellular in vitro model by using immortalized corneal endothelial cells obtained from late-onset FECD and control patients and examined the involvement of epithelial mesenchymal transition (EMT) on excessive ECM production. We demonstrate that the EMT-inducing genes ZEB1 and SNAI1 were highly expressed in corneal endothelial cells in FECD and were involved in excessive production of ECM proteins, such as type I collagen and fibronectin through the transforming growth factor (TGF)-β signaling pathway. Furthermore, we found that SB431542, a specific inhibitor of TGF-β type I ALK receptors, suppressed the expression of ZEB1 and Snail1 followed by reduced production of ECM. These findings suggest that increased expression levels of ZEB1 and Snail1 in FECD cells were responsible for an increased responsiveness to TGF-β present in the aqueous humor and excessive production of ECM. In addition, these results suggest that the regulation of EMT-related genes by blocking the TGF-β signaling pathway may be a feasible therapeutic strategy for FECD. DA - 2015/11// PY - 2015 DO - 10.1038/labinvest.2015.111 DP - PubMed VL - 95 IS - 11 SP - 1291 EP - 1304 J2 - Lab. Invest. LA - eng SN - 1530-0307 L1 - https://www.nature.com/articles/labinvest2015111.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/26302187 KW - Cell Line, Transformed KW - Extracellular Matrix KW - Fuchs' Endothelial Dystrophy KW - Gene Knockdown Techniques KW - Homeodomain Proteins KW - Humans KW - Snail Family Transcription Factors KW - Transcription Factors KW - Transforming Growth Factor beta KW - Up-Regulation KW - Zinc Finger E-box-Binding Homeobox 1 ER - TY - JOUR TI - Pathological molecular mechanism of symptomatic late-onset Fuchs endothelial corneal dystrophy by bioinformatic analysis AU - Cui, Zekai AU - Zeng, Qiaolang AU - Guo, Yonglong AU - Liu, Shiwei AU - Wang, Peiyuan AU - Xie, Mengyuan AU - Chen, Jiansu T2 - PLOS ONE A2 - Krahe, Ralf DA - 2018/05/22/ PY - 2018 DO - 10.1371/journal.pone.0197750 DP - Crossref VL - 13 IS - 5 SP - e0197750 LA - en SN - 1932-6203 UR - http://dx.plos.org/10.1371/journal.pone.0197750 Y2 - 2019/02/01/04:18:13 L1 - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0197750&type=printable ER - TY - JOUR TI - Corneal Endothelial Cell Migration and Proliferation Enhanced by Rho Kinase (ROCK) Inhibitors in In Vitro and In Vivo Models AU - Meekins, Landon C. AU - Rosado-Adames, Noel AU - Maddala, Rupalatha AU - Zhao, Jiagang J. AU - Rao, Ponugoti V. AU - Afshari, Natalie A. T2 - Investigative Opthalmology & Visual Science DA - 2016/12/12/ PY - 2016 DO - 10.1167/iovs.16-20414 DP - Crossref VL - 57 IS - 15 SP - 6731 LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?doi=10.1167/iovs.16-20414 Y2 - 2019/02/01/04:03:47 L1 - https://iovs.arvojournals.org/data/journals/iovs/935913/i1552-5783-57-15-6731.pdf ER - TY - JOUR TI - Predicative Factors for Corneal Endothelial Cell Migration AU - Soh, Yu Qiang AU - Peh, Gary AU - George, Benjamin Lawrence AU - Seah, Xin Yi AU - Primalani, Nishal Kishinchand AU - Adnan, Khadijah AU - Mehta, Jodhbir Singh T2 - Investigative Opthalmology & Visual Science DA - 2016/02/03/ PY - 2016 DO - 10.1167/iovs.15-18300 DP - Crossref VL - 57 IS - 2 SP - 338 LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?doi=10.1167/iovs.15-18300 Y2 - 2019/02/01/00:13:38 L1 - https://iovs.arvojournals.org/data/journals/iovs/934916/i1552-5783-57-2-338.pdf ER - TY - JOUR TI - Fluid transport by the cornea endothelium is dependent on buffering lactic acid efflux AU - Li, Shimin AU - Kim, Edward AU - Bonanno, Joseph A. T2 - American Journal of Physiology-Cell Physiology DA - 2016/07// PY - 2016 DO - 10.1152/ajpcell.00095.2016 DP - Crossref VL - 311 IS - 1 SP - C116 EP - C126 LA - en SN - 0363-6143, 1522-1563 UR - http://www.physiology.org/doi/10.1152/ajpcell.00095.2016 Y2 - 2019/01/31/23:49:04 ER - TY - JOUR TI - Lactate-H + Transport Is a Significant Component of the In Vivo Corneal Endothelial Pump AU - Nguyen, Tracy T. AU - Bonanno, Joseph A. T2 - Investigative Opthalmology & Visual Science DA - 2012/04/16/ PY - 2012 DO - 10.1167/iovs.12-9475 DP - Crossref VL - 53 IS - 4 SP - 2020 LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?doi=10.1167/iovs.12-9475 Y2 - 2019/01/31/23:43:55 L1 - https://iovs.arvojournals.org/data/journals/iovs/933465/i1552-5783-53-4-2020.pdf ER - TY - CHAP TI - Production and Flow of Aqueous Humor AU - Gabelt, B'Ann True AU - Paul L. Kaufman T2 - Adler's Physiology of the Eye ET - 11th edition PB - W B Saunders Company SN - 978-0-323-05714-1 978-0-323-08116-0 ER - TY - CHAP TI - Anatomy & Embryology of the Eye AU - Riordan-Eva, Paul T2 - Vaughan & Asbury's General Ophthalmology, 19e A2 - Riordan-Eva, Paul A2 - Augsburger, James J. AB - A thorough understanding of the anatomy of the eye, orbit, visual pathways, upper cranial nerves, and central pathways for the control of eye movements is a prerequisite for proper interpretation of diseases having ocular manifestations. Furthermore, such anatomic knowledge is essential to the proper planning and safe execution of ocular and orbital surgery. Whereas most knowledge of these matters is based on anatomic dissections, either postmortem or during surgery, noninvasive techniques—particularly magnetic resonance imaging (MRI), ultrasonography, and optical coherence tomography (OCT)—are increasingly providing additional information. Investigating the embryology of the eye is more difficult because of the relative scarcity of suitable human material, and thus there is still great reliance on animal studies with the inherent difficulties in inferring parallels in human development. Nevertheless, a great deal is known about the embryology of the human eye, and—together with the recent expansion in molecular genetic—this has led to a much deeper understanding of developmental anomalies of the eye. CY - New York, NY DA - 2017/// PY - 2017 IS - Book, Section PB - McGraw-Hill Education UR - accessmedicine.mhmedical.com/content.aspx?aid=1144466589 Y2 - 2019/01/30/ ER - TY - JOUR TI - Ultraviolet Light Transmission through the Human Corneal Stroma Is Reduced in the Periphery AU - Doutch, James J. AU - Quantock, Andrew J. AU - Joyce, Nancy C. AU - Meek, Keith M. T2 - Biophysical Journal DA - 2012/03// PY - 2012 DO - 10.1016/j.bpj.2012.02.023 DP - Crossref VL - 102 IS - 6 SP - 1258 EP - 1264 LA - en SN - 00063495 UR - https://linkinghub.elsevier.com/retrieve/pii/S0006349512002263 Y2 - 2019/01/30/17:36:55 L1 - https://europepmc.org/articles/pmc3309274?pdf=render ER - TY - JOUR TI - A systematic review on the impact of diabetes mellitus on the ocular surface AU - Shih, K. Co AU - Lam, K. S.-L. AU - Tong, L. T2 - Nutrition & Diabetes AB - Diabetes mellitus is associated with extensive morbidity and mortality in any human community. It is well understood that the burden of diabetes is attributed to chronic progressive damage in major end-organs, but it is underappreciated that the most superficial and transparent organ affected by diabetes is the cornea. Different corneal components (epithelium, nerves, immune cells and endothelium) underpin specific systemic complications of diabetes. Just as diabetic retinopathy is a marker of more generalized microvascular disease, corneal nerve changes can predict peripheral and autonomic neuropathy, providing a window of opportunity for early treatment. In addition, alterations of immune cells in corneas suggest an inflammatory component in diabetic complications. Furthermore, impaired corneal epithelial wound healing may also imply more widespread disease. The non-invasiveness and improvement in imaging technology facilitates the emergence of new screening tools. Systemic control of diabetes can improve ocular surface health, possibly aided by anti-inflammatory and vasoprotective agents. DA - 2017//03/20 PY - 2017 DO - 10.1038/nutd.2017.4 DP - PubMed VL - 7 IS - 3 SP - e251 J2 - Nutr Diabetes LA - eng SN - 2044-4052 L1 - https://www.nature.com/articles/nutd20174.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/28319106 KW - Corneal Diseases KW - Diabetes Mellitus, Type 1 KW - Diabetes Mellitus, Type 2 KW - Epithelium, Corneal KW - Humans ER - TY - ELEC TI - A systematic review on the impact of diabetes mellitus on the ocular surface | Nutrition & Diabetes UR - https://www.nature.com/articles/nutd20174 Y2 - 2019/01/27/23:42:54 L2 - https://www.nature.com/articles/nutd20174 ER - TY - ELEC TI - Diabetes AB - Una dieta saludable, la actividad física regular, el mantenimiento de un peso corporal normal y la evitación del consumo de tabaco pueden prevenir la diabetes de tipo 2 o retrasar su aparición. LA - es UR - https://www.who.int/es/news-room/fact-sheets/detail/diabetes Y2 - 2019/01/27/23:04:50 L2 - https://www.who.int/es/news-room/fact-sheets/detail/diabetes ER - TY - ELEC TI - Deleterious impact of hyperglycemia on cystic fibrosis airway ion transport and epithelial repair - ScienceDirect UR - https://www.sciencedirect.com/science/article/pii/S1569199315001022 Y2 - 2019/01/10/01:22:33 L2 - https://www.sciencedirect.com/science/article/pii/S1569199315001022 ER - TY - JOUR TI - High Glucose Induces CCL20 in Proximal Tubular Cells via Activation of the KCa3.1 Channel AU - Huang, Chunling AU - Pollock, Carol A. AU - Chen, Xin-Ming T2 - PLOS ONE AB - Background Inflammation plays a key role in the development and progression of diabetic nephropathy (DN). KCa3.1, a calcium activated potassium channel protein, is associated with vascular inflammation, atherogenesis, and proliferation of endothelial cells, macrophages, and fibroblasts. We have previously demonstrated that the KCa3.1 channel is activated by TGF-β1 and blockade of KCa3.1 ameliorates renal fibrotic responses in DN through inhibition of the TGF-β1 pathway. The present study aimed to identify the role of KCa3.1 in the inflammatory responses inherent in DN. Methods Human proximal tubular cells (HK2 cells) were exposed to high glucose (HG) in the presence or absence of the KCa3.1 inhibitor TRAM34 for 6 days. The proinflammatory cytokine chemokine (C-C motif) ligand 20 (CCL20) expression was examined by real-time PCR and enzyme-linked immunosorbent assay (ELISA). The activity of nuclear factor-κB (NF-κB) was measured by nuclear extraction and electrophoretic mobility shift assay (EMSA). In vivo, the expression of CCL20, the activity of NF-κB and macrophage infiltration (CD68 positive cells) were examined by real-time PCR and/or immunohistochemistry staining in kidneys from diabetic or KCa3.1-/- mice, and in eNOS-/- diabetic mice treated with the KCa3.1 channel inhibitor TRAM34. Results In vitro data showed that TRAM34 inhibited CCL20 expression and NF-κB activation induced by HG in HK2 cells. Both mRNA and protein levels of CCL20 significantly decreased in kidneys of diabetic KCa3.1-/- mice compared to diabetic wild type mice. Similarly, TRAM34 reduced CCL20 expression and NF-κB activation in diabetic eNOS-/- mice compared to diabetic controls. Blocking the KCa3.1 channel in both animal models led to a reduction in phosphorylated NF-κB. Conclusions Overexpression of CCL20 in human proximal tubular cells is inhibited by blockade of KCa3.1 under diabetic conditions through inhibition of the NF-κB pathway. DA - 2014/04/14/undefined PY - 2014 DO - 10.1371/journal.pone.0095173 DP - PLoS Journals VL - 9 IS - 4 SP - e95173 J2 - PLOS ONE LA - en SN - 1932-6203 UR - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0095173 Y2 - 2019/01/10/01:22:04 L1 - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0095173&type=printable L2 - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0095173 KW - Chemokines KW - Diabetes mellitus KW - Gene expression KW - Inflammation KW - Inflammatory diseases KW - Kidneys KW - Macrophages KW - Transcription factors ER - TY - JOUR TI - Targeting potassium channels in cancer AU - Huang, Xi AU - Jan, Lily Yeh T2 - The Journal of Cell Biology AB - Potassium channels are pore-forming transmembrane proteins that regulate a multitude of biological processes by controlling potassium flow across cell membranes. Aberrant potassium channel functions contribute to diseases such as epilepsy, cardiac arrhythmia, and neuromuscular symptoms collectively known as channelopathies. Increasing evidence suggests that cancer constitutes another category of channelopathies associated with dysregulated channel expression. Indeed, potassium channel-modulating agents have demonstrated antitumor efficacy. Potassium channels regulate cancer cell behaviors such as proliferation and migration through both canonical ion permeation-dependent and noncanonical ion permeation-independent functions. Given their cell surface localization and well-known pharmacology, pharmacological strategies to target potassium channel could prove to be promising cancer therapeutics. DA - 2014/07/21/ PY - 2014 DO - 10.1083/jcb.201404136 DP - PubMed VL - 206 IS - 2 SP - 151 EP - 162 J2 - J. Cell Biol. LA - eng SN - 1540-8140 L1 - http://jcb.rupress.org/content/jcb/206/2/151.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/25049269 KW - Cell Cycle KW - Cell Movement KW - Cell Proliferation KW - Humans KW - Models, Biological KW - Neoplasm Metastasis KW - Neoplasms KW - Potassium Channel Blockers KW - Potassium Channels KW - Tumor Microenvironment ER - TY - JOUR TI - Calcium-Activated Potassium Channel KCa3.1 in Lung Dendritic Cell Migration AU - Shao, Zhifei AU - Makinde, Toluwalope O. AU - Agrawal, Devendra K. T2 - American Journal of Respiratory Cell and Molecular Biology AB - Migration to draining lymph nodes is a critical requirement for dendritic cells (DCs) to control T-cell–mediated immunity. The calcium-activated potassium channel KCa3.1 has been shown to be involved in regulating cell migration in multiple cell types. In this study, KCa3.1 expression and its functional role in lung DC migration were examined. Fluorescence-labeled antigen was intranasally delivered into mouse lungs to label lung Ag-carrying DCs. Lung CD11chighCD11blow and CD11clowCD11bhigh DCs from PBS-treated and ovalbumin (OVA)-sensitized mice were sorted using MACS and FACS. Indo-1 and DiBAC4(3) were used to measure intracellular Ca2+ and membrane potential, respectively. The mRNA expression of KCa3.1 was examined using real-time PCR. Expression of KCa3.1 protein and CCR7 was measured using flow cytometry. Migration of two lung DC subsets to lymphatic chemokines was examined using TransWell in the absence or presence of the KCa3.1 blocker TRAM-34. OVA sensitization up-regulated mRNA and protein expression of KCa3.1 in lung DCs, with a greater response by the CD11chighCD11blow than CD11clowCD11bhigh DCs. Although KCa3.1 expression in Ag-carrying DCs was higher than that in non–Ag-carrying DCs in OVA-sensitized mice, the difference was not as prominent. However, Ag-carrying lung DCs expressed significantly higher CCR7 than non–Ag-carrying DCs. CCL19, CCL21, and KCa3.1 activator 1-EBIO induced an increase in intracellular calcium in both DC subsets. In addition, 1-EBIO–induced calcium increase was suppressed by TRAM-34. In vitro blockade of KCa3.1 with TRAM-34 impaired CCL19/CCL21-induced transmigration. In conclusion, KCa3.1 expression in lung DCs is up-regulated by OVA sensitization in both lung DC subsets, and KCa3.1 is involved in lung DC migration to lymphatic chemokines. DA - 2011/11// PY - 2011 DO - 10.1165/rcmb.2010-0514OC DP - PubMed Central VL - 45 IS - 5 SP - 962 EP - 968 J2 - Am J Respir Cell Mol Biol SN - 1044-1549 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3262686/ Y2 - 2019/01/10/01:17:33 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3262686/pdf/AJRCMB455962.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3262686/ ER - TY - JOUR TI - Alterations in mitochondrial function and cytosolic calcium induced by hyperglycemia are restored by mitochondrial transcription factor A in cardiomyocytes AU - Suarez, Jorge AU - Hu, Yong AU - Makino, Ayako AU - Fricovsky, Eduardo AU - Wang, Hong AU - Dillmann, Wolfgang H. T2 - American Journal of Physiology-Cell Physiology AB - Mitochondrial transcription factor A (TFAM) is essential for mitochondrial DNA transcription and replication. TFAM transcriptional activity is decreased in diabetic cardiomyopathy; however, the functional implications are unknown. We hypothesized that a reduced TFAM activity may be responsible for some of the alterations caused by hyperglycemia. Therefore, we investigated the effect of TFAM overexpression on hyperglycemia-induced cytosolic calcium handling and mitochondrial abnormalities. Neonatal rat cardiomyocytes were exposed to high glucose (30 mM) for 48 h, and we examined whether TFAM overexpression, by protecting mitochondrial DNA, could reestablish calcium fluxes and mitochondrial alterations toward normal. Our results shown that TFAM overexpression increased to more than twofold mitochondria copy number in cells treated either with normal (5.5 mM) or high glucose. ATP content was reduced by 30% and mitochondrial calcium decreased by 40% after high glucose. TFAM overexpression returned these parameters to even higher than control values. Calcium transients were prolonged by 70% after high glucose, which was associated with diminished sarco(endo)plasmic reticulum Ca2+-ATPase 2a and cytochrome-c oxidase subunit 1 expression. These parameters were returned to control values after TFAM overexpression. High glucose-induced protein oxidation was reduced by TFAM overexpression, indicating a reduction of the high glucose-induced oxidative stress. In addition, we found that TFAM activity can be modulated by O-linked β-N-acetylglucosamine glycosylation. In conclusion, TFAM overexpression protected cell function against the damage induced by high glucose in cardiomyocytes. DA - 2008/12/01/ PY - 2008 DO - 10.1152/ajpcell.00076.2008 DP - physiology.org (Atypon) VL - 295 IS - 6 SP - C1561 EP - C1568 J2 - American Journal of Physiology-Cell Physiology SN - 0363-6143 UR - https://www.physiology.org/doi/full/10.1152/ajpcell.00076.2008 Y2 - 2018/12/14/09:47:18 L1 - https://www.physiology.org/doi/pdf/10.1152/ajpcell.00076.2008 L2 - https://www.physiology.org/doi/full/10.1152/ajpcell.00076.2008 ER - TY - JOUR TI - Stress-induced corneal epithelial apoptosis mediated by K+ channel activation AU - Lu, Luo T2 - Progress in Retinal and Eye Research AB - One of the functional roles of the corneal epithelial layer is to protect the cornea, lens and other underlying ocular structures from damages caused by environmental insults. It is important for corneal epithelial cells to maintain this function by undergoing continuous renewal through a dynamic process of wound healing. Previous studies in corneal epithelial cells have provided substantial evidence showing that environmental insults, such as ultraviolet (UV) irradiation and other biohazards, can induce stress-related cellular responses resulting in apoptosis and thus interrupt the dynamic process of wound healing. We found that UV irradiation-induced apoptotic effects in corneal epithelial cells are started by the hyperactivation of K+ channels in the cell membrane resulting in a fast loss of intracellular K+ ions. Recent studies provide further evidence indicating that these complex responses in corneal epithelial cells are resulted from the activation of stress-related signaling pathways mediated by K+ channel activity. The effect of UV irradiation on corneal epithelial cell fate shares common signaling mechanisms involving the activation of intracellular responses that are often activated by the stimulation of various cytokines. One piece of evidence for making this distinction is that at early times UV irradiation activates a Kv3.4 channel in corneal epithelial cells to elicit activation of c-Jun N-terminal kinase cascades and p53 activation leading to cell cycle arrest and apoptosis. The hypothetic model is that UV-induced potassium channel hyperactivity as an early event initiates fast cell shrinkages due to the loss of intracellular potassium, resulting in the activation of scaffolding protein kinases and cytoskeleton reorganizations. This review article presents important control mechanisms that determine Kv channel activity-mediated cellular responses in corneal epithelial cells, involving activation of stress-induced signaling pathways, arrests of cell cycle progression and/or induction of apoptosis. DA - 2006/11// PY - 2006 DO - 10.1016/j.preteyeres.2006.07.004 DP - PubMed VL - 25 IS - 6 SP - 515 EP - 538 J2 - Prog Retin Eye Res LA - eng SN - 1350-9462 L1 - https://europepmc.org/articles/pmc1995124?pdf=render L2 - http://www.ncbi.nlm.nih.gov/pubmed/16962363 KW - Animals KW - Apoptosis KW - Epithelium, Corneal KW - Humans KW - JNK Mitogen-Activated Protein Kinases KW - Potassium Channels KW - Tumor Necrosis Factor-alpha KW - Tumor Suppressor Protein p53 KW - Ultraviolet Rays ER - TY - JOUR TI - Minocycline is cytoprotective in human corneal endothelial cells and induces anti-apoptotic B-cell CLL/lymphoma 2 (Bcl-2) and X-linked inhibitor of apoptosis (XIAP) AU - Kernt, Marcus AU - Hirneiss, C. AU - Neubauer, A. S. AU - Kampik, A. T2 - The British Journal of Ophthalmology AB - INTRODUCTION: Loss of corneal endothelial cells (CECs) is one major factor limiting transplant clarity and survival after keratoplasty. Amongst other factors, apoptosis due to cellular stress is responsible for these problems. This study investigates the possible anti-apoptotic and cytoprotective effects of minocycline on a human corneal endothelial cell line (HCEC-SV40) cultured under oxidative stress and with transforming growth factor beta (TGF-beta). METHODS: CECs were treated with 1-150 microM minocycline. Cell viability and the median inhibitory concentration (IC(50)) were evaluated after 48 h and after H(2)O(2) treatment (tetrazolium dye reduction assay and live-dead assay). Expression of B-cell CLL/lymphoma 2 (Bcl-2) and X-linked inhibitor of apoptosis (XIAP) and their mRNA were assessed by reverse transcriptase (RT)-PCR and western blot analysis after treatment with minocycline alone and consecutive incubation with 200 microM H(2)O(2) and TGF-beta2. A quantitative detection of histone-associated DNA fragmentation by ELISA was performed. RESULTS: Minocycline concentrations from 1-50 microM showed no toxic effects on CECs. Pre-treatment with 10-40 microM minocycline led to an increase in viability after H(2)O(2) treatment. In addition, minocycline pre-treatment attenuated the increase of histone-associated DNA fragmentation after treatment with H(2)O(2) and TGF-beta2 significantly. When CECs were treated with minocycline and then consecutively with H(2)O(2) or TGF-beta2, RT-PCR and western blot analysis yielded an overexpression of Bcl-2 and XIAP. CONCLUSION: In this study minocycline prevented apoptotic cell death in cultured CECs in vitro. Our results suggest that minocycline might offer cytoprotective properties that might help to prevent loss of corneal endothelial cells in vivo. DA - 2010/07// PY - 2010 DO - 10.1136/bjo.2009.165092 DP - PubMed VL - 94 IS - 7 SP - 940 EP - 946 J2 - Br J Ophthalmol LA - eng SN - 1468-2079 L1 - https://epub.ub.uni-muenchen.de/18004/1/oa_18004.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/20606027 KW - Apoptosis KW - Cells, Cultured KW - Cytoprotection KW - Dose-Response Relationship, Drug KW - Endothelium, Corneal KW - Gene Expression Regulation KW - Humans KW - Minocycline KW - Proto-Oncogene Proteins c-bcl-2 KW - RNA, Messenger KW - X-Linked Inhibitor of Apoptosis Protein ER - TY - JOUR TI - The pathobiology of diabetic complications: a unifying mechanism AU - Brownlee, Michael T2 - Diabetes DA - 2005/06// PY - 2005 DP - PubMed VL - 54 IS - 6 SP - 1615 EP - 1625 J2 - Diabetes LA - eng SN - 0012-1797 ST - The pathobiology of diabetic complications L1 - https://diabetes.diabetesjournals.org/content/54/6/1615.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/15919781 KW - Animals KW - Diabetes Complications KW - Humans KW - Hyperglycemia KW - Mitochondria ER - TY - JOUR TI - Limited Mitochondrial Permeabilization Causes DNA Damage and Genomic Instability in the Absence of Cell Death AU - Ichim, Gabriel AU - Lopez, Jonathan AU - Ahmed, Shafiq U. AU - Muthalagu, Nathiya AU - Giampazolias, Evangelos AU - Delgado, M. Eugenia AU - Haller, Martina AU - Riley, Joel S. AU - Mason, Susan M. AU - Athineos, Dimitris AU - Parsons, Melissa J. AU - van de Kooij, Bert AU - Bouchier-Hayes, Lisa AU - Chalmers, Anthony J. AU - Rooswinkel, Rogier W. AU - Oberst, Andrew AU - Blyth, Karen AU - Rehm, Markus AU - Murphy, Daniel J. AU - Tait, Stephen W.G. T2 - Molecular Cell DA - 2015/03// PY - 2015 DO - 10.1016/j.molcel.2015.01.018 DP - Crossref VL - 57 IS - 5 SP - 860 EP - 872 LA - en SN - 10972765 UR - https://linkinghub.elsevier.com/retrieve/pii/S1097276515000192 Y2 - 2018/11/26/14:33:48 L1 - https://sure.sunderland.ac.uk/6006/1/AHMED%20SURE%206006.pdf ER - TY - JOUR TI - S-nitrosylation of Drp1 mediates beta-amyloid-related mitochondrial fission and neuronal injury AU - Cho, Dong-Hyung AU - Nakamura, Tomohiro AU - Fang, Jianguo AU - Cieplak, Piotr AU - Godzik, Adam AU - Gu, Zezong AU - Lipton, Stuart A. T2 - Science (New York, N.Y.) AB - Mitochondria continuously undergo two opposing processes, fission and fusion. The disruption of this dynamic equilibrium may herald cell injury or death and may contribute to developmental and neurodegenerative disorders. Nitric oxide functions as a signaling molecule, but in excess it mediates neuronal injury, in part via mitochondrial fission or fragmentation. However, the underlying mechanism for nitric oxide-induced pathological fission remains unclear. We found that nitric oxide produced in response to beta-amyloid protein, thought to be a key mediator of Alzheimer's disease, triggered mitochondrial fission, synaptic loss, and neuronal damage, in part via S-nitrosylation of dynamin-related protein 1 (forming SNO-Drp1). Preventing nitrosylation of Drp1 by cysteine mutation abrogated these neurotoxic events. SNO-Drp1 is increased in brains of human Alzheimer's disease patients and may thus contribute to the pathogenesis of neurodegeneration. DA - 2009/04/03/ PY - 2009 DO - 10.1126/science.1171091 DP - PubMed VL - 324 IS - 5923 SP - 102 EP - 105 J2 - Science LA - eng SN - 1095-9203 L1 - https://europepmc.org/articles/pmc2823371?pdf=render L2 - http://www.ncbi.nlm.nih.gov/pubmed/19342591 KW - Alzheimer Disease KW - Amino Acid Motifs KW - Amyloid beta-Peptides KW - Animals KW - Cell Line KW - Cell Line, Tumor KW - Cerebral Cortex KW - Cysteine KW - Female KW - GTP Phosphohydrolases KW - Humans KW - Male KW - Mice KW - Mice, Transgenic KW - Microtubule-Associated Proteins KW - Mitochondria KW - Mitochondrial Proteins KW - Models, Molecular KW - Mutation KW - Neurons KW - Nitric Oxide KW - Peptide Fragments KW - Protein Multimerization KW - Protein Structure, Tertiary KW - S-Nitrosothiols ER - TY - JOUR TI - Necroptosis, necrosis and secondary necrosis converge on similar cellular disintegration features AU - Vanden Berghe, T. AU - Vanlangenakker, N. AU - Parthoens, E. AU - Deckers, W. AU - Devos, M. AU - Festjens, N. AU - Guerin, C. J. AU - Brunk, U. T. AU - Declercq, W. AU - Vandenabeele, P. T2 - Cell Death and Differentiation AB - Necroptosis, necrosis and secondary necrosis following apoptosis represent different modes of cell death that eventually result in similar cellular morphology including rounding of the cell, cytoplasmic swelling, rupture of the plasma membrane and spilling of the intracellular content. Subcellular events during tumor necrosis factor (TNF)-induced necroptosis, H(2)O(2)-induced necrosis and anti-Fas-induced secondary necrosis were studied using high-resolution time-lapse microscopy. The cellular disintegration phase of the three types of necrosis is characterized by an identical sequence of subcellular events, including oxidative burst, mitochondrial membrane hyperpolarization, lysosomal membrane permeabilization and plasma membrane permeabilization, although with different kinetics. H(2)O(2)-induced necrosis starts immediately by lysosomal permeabilization. In contrast, during TNF-mediated necroptosis and anti-Fas-induced secondary necrosis, this is a late event preceded by a defined signaling phase. TNF-induced necroptosis depends on receptor-interacting protein-1 kinase, mitochondrial complex I and cytosolic phospholipase A(2) activities, whereas H(2)O(2)-induced necrosis requires iron-dependent Fenton reactions. DA - 2010/06// PY - 2010 DO - 10.1038/cdd.2009.184 DP - PubMed VL - 17 IS - 6 SP - 922 EP - 930 J2 - Cell Death Differ. LA - eng SN - 1476-5403 L1 - https://www.nature.com/articles/cdd2009184.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/20010783 KW - Animals KW - Cell Line, Tumor KW - Cell Membrane Permeability KW - Electron Transport Complex I KW - Hydrogen Peroxide KW - Iron KW - Lysosomes KW - Membrane Potential, Mitochondrial KW - Mice KW - Necrosis KW - Phospholipases A2, Cytosolic KW - Reactive Oxygen Species KW - Receptor-Interacting Protein Serine-Threonine Kinases KW - Tumor Necrosis Factor-alpha ER - TY - JOUR TI - Ultraviolet Radiation: Cellular Antioxidant Response and the Role of Ocular Aldehyde Dehydrogenase Enzymes: AU - Marchitti, Satori A AU - Chen, Ying AU - Thompson, David C AU - Vasiliou, Vasilis T2 - Eye & Contact Lens: Science & Clinical Practice DA - 2011/07// PY - 2011 DO - 10.1097/ICL.0b013e3182212642 DP - Crossref VL - 37 IS - 4 SP - 206 EP - 213 LA - en SN - 1542-2321 ST - Ultraviolet Radiation UR - http://content.wkhealth.com/linkback/openurl?sid=WKPTLP:landingpage&an=00140068-201107000-00007 Y2 - 2018/11/15/13:11:40 L1 - https://europepmc.org/articles/pmc3356694?pdf=render ER - TY - JOUR TI - The Role of the Reactive Oxygen Species and Oxidative Stress in the Pathomechanism of the Age-Related Ocular Diseases and Other Pathologies of the Anterior and Posterior Eye Segments in Adults AU - Nita, Małgorzata AU - Grzybowski, Andrzej T2 - Oxidative Medicine and Cellular Longevity DA - 2016/// PY - 2016 DO - 10.1155/2016/3164734 DP - Crossref VL - 2016 SP - 1 EP - 23 LA - en SN - 1942-0900, 1942-0994 UR - http://www.hindawi.com/journals/omcl/2016/3164734/ Y2 - 2018/11/15/12:57:37 L1 - https://europepmc.org/articles/pmc4736974?pdf=render ER - TY - JOUR TI - Proliferative response of corneal endothelial cells from young and older donors AU - Zhu, Cheng AU - Joyce, Nancy C. T2 - Investigative Ophthalmology & Visual Science AB - PURPOSE: To compare the effect of epidermal growth factor (EGF), nerve growth factor (NGF), platelet-derived growth factor-BB (PDGF-BB), bovine pituitary extract, and fetal bovine serum (FBS), alone or in combination, on proliferation of human corneal endothelial cells (HCEC) cultured from young (<30 years old) and older donors (>50 years old). METHODS: Corneas from donors 2 to 79 years old were obtained from the National Disease Research Interchange. Descemet's membrane with intact endothelium was dissected. Cells were isolated by EDTA treatment and cultured to confluence. The HCEC marker, antibody 9.3.E, tested for pure endothelial populations. Antibody Ki67 and ZO-1 tested either before or after cultured cells reached confluence to indicate cell proliferation and cell-cell contact formation. Cell morphology was documented by inverted phase-contrast microscopy. Passages I through VII were used to test the effect of various factors on cell proliferation. For each study, equal numbers of cells were seeded, maintained overnight in 4% FBS to permit cell attachment, washed, and incubated for up to 3 weeks in one of the following: modified Eagle's Minimum Essential Medium (Opti-MEM-I) alone; Opti-MEM-I plus EGF, NGF, PDGF-BB, bovine pituitary extract, or FBS; or a combination of factors. At various times after seeding, cell numbers were determined by electronic cell counter. For each condition, three separate wells were tested and each sample was counted three times. Studies were repeated at least twice using cells from different donors and age groups. Within each study, a one-way ANOVA test was performed to analyze statistical significance. RESULTS: Cells stained positively with antibody 9.3.E, indicating isolation of HCEC and lack of contamination with epithelial cells or keratocytes. Positive staining of Ki67, indicating cycling cells, was found in subconfluent cultures. Plasma membrane-associated ZO-1 staining and lack of Ki67 staining indicated that cultured cells formed a contact-inhibited monolayer. Cultured cells decreased in density, increased in size, and became more heterogeneous depending on donor age and on the number of passages. Incubation in OptiMEM-I promoted attachment and induced a moderate proliferative response above that of MEM (P < 0.001). In general, proliferative responses to growth stimuli were relatively slow, with cell counts generally plateauing 10 to 14 days after exposure to growth-promoting agents. EGF yielded a broad, dose-dependent effect and, at 5-50 ng/mL, peak cell counts were significantly higher (P < 0.001) than basal levels. EGF consistently stimulated proliferation in cells from younger donors, but was less effective in stimulating growth of cells from older donors. NGF did not show a consistent significant stimulatory effect at any concentration tested. PDGF-BB (25 ng/mL) tended to stimulate growth to a greater extent than EGF (P < 0.05) in cultures from the same donor. Pituitary extract significantly increased counts at 1.0 (P < 0.05) to 100 ug/mL (P < 0.001). PDGF-BB plus pituitary extract demonstrated greater stimulation than pituitary extract (P < 0.01) or PDGF-BB alone (P < 0.01). FBS (1%-8%) increased cell numbers in a dose-dependent manner, and, at 4%-8%, yielded counts significantly higher (P < 0.001) than that of any single growth-promoting agent tested. CONCLUSIONS: HCEC from both young and older donors can proliferate in vitro in response to growth-promoting agents. Proliferation in the presence of multiple mitogens ceased when confluence was reached, indicating the formation of a contact-inhibited monolayer. In general, cells cultured from young donors were more responsive to the agents tested, but the relative response of HCEC to these agents was similar, regardless of donor age. The relative difference in the extent of the response of the same cell population to different mitogens suggests that these mitogens induce different downstream signals. The relatively robust proliferative response of HCEC to FBS may involve stimulation of multiple downstream signaling pathways may involve stimulation of multiple downstream signaling pathways and/or induce more sustained downstream signaling than the other growth-promoting agents tested. DA - 2004/06// PY - 2004 DP - PubMed VL - 45 IS - 6 SP - 1743 EP - 1751 J2 - Invest. Ophthalmol. Vis. Sci. LA - eng SN - 0146-0404 L2 - http://www.ncbi.nlm.nih.gov/pubmed/15161835 KW - Adolescent KW - Adult KW - Aged KW - Aging KW - Cell Adhesion KW - Cell Count KW - Cell Division KW - Cells, Cultured KW - Child KW - Child, Preschool KW - Dose-Response Relationship, Drug KW - Drug Therapy, Combination KW - Endothelium, Corneal KW - Fluorescent Antibody Technique, Indirect KW - Growth Substances KW - Humans KW - Ki-67 Antigen KW - Membrane Proteins KW - Microscopy, Phase-Contrast KW - Middle Aged KW - Phosphoproteins KW - Tissue Donors KW - Zonula Occludens-1 Protein ER - TY - JOUR TI - Cell cycle kinetics in corneal endothelium from old and young donors AU - Senoo, T. AU - Joyce, N. C. T2 - Investigative Ophthalmology & Visual Science AB - PURPOSE: To compare cell cycle kinetics in corneal endothelial cells from young and old donors. METHODS: Human corneas were obtained from the eye bank and separated into two groups: young (19 corneas, <30 years of age) and old (40 corneas, >50 years of age). Corneas were cut in quarters, and the endothelium was released from contact inhibition by producing a 2-mm scrape wound. Unwounded endothelium acted as a negative control. Corneal pieces were exposed for 24, 36, 48, 60, 72, and 84 hours to medium containing 10% fetal bovine serum, 20 ng/ml fibroblast growth factor, and 50 mg/ml gentamicin or the same medium supplemented with 10 ng/ml epidermal growth factor (EGF). Tissue was fixed, immunostained for Ki67 (a marker for the late G1-through M-phase) or for 5-bromo-2'-deoxyuridine (BrdU; a marker for the S-phase), and mounted in medium containing propidium iodide (PI) to visualize all nuclei. Confocal images were evaluated using an image analysis program to count Ki67-positive and PI-stained cells and to evaluate cell cycle position. Cells were counted in 15x100 microm2 areas randomly selected from each wound, and the mean was used for subsequent calculations. RESULTS: Human corneal endothelial cells could be reliably scored for their position within the cell cycle using Ki67 staining patterns. In both age groups, cells repopulating the wound area stained positively for Ki67, whereas no Ki67 staining was observed in unwounded areas under any condition tested. Cells from old donors treated with fetal bovine serum and FGF stained positively for Ki67, indicating that these cells were actively cycling. Compared with cells from young donors, old cells entered the cell cycle more slowly (48 versus 36 hours), the peak of Ki67 staining occurred later (72 versus 60 hours), and fewer cells proliferated (23% versus 47%) or exhibited mitotic figures (4% versus 7%). Addition of EGF to the culture medium increased Ki67 staining in both groups, but the effect on old cells was more dramatic. More cells from old donors entered the cell cycle by 36 hours after wounding, the number of proliferating cells increased 1.6-fold, and the relative number of mitotic figures increased 2.5-fold over cells treated in the absence of EGF. CONCLUSIONS: Regardless of donor age, corneal endothelial cells can enter and complete the cell cycle. In the presence of fetal bovine serum and FGF, cells from old donors can proliferate but respond more slowly and to a lesser extent than cells from young donors. EGF added to the medium stimulates cells from old donors to enter the cell cycle faster, increases the relative number of actively cycling cells, and increases the number of cells exhibiting mitotic figures. The resultant hypothesis is that it is possible to stimulate a significant proliferative response in corneal endothelial cells from old individuals. Administration of an optimal combination of stimulatory growth factors is required under conditions in which cells have been transiently released from contact inhibition. DA - 2000/03// PY - 2000 DP - PubMed VL - 41 IS - 3 SP - 660 EP - 667 J2 - Invest. Ophthalmol. Vis. Sci. LA - eng SN - 0146-0404 L2 - http://www.ncbi.nlm.nih.gov/pubmed/10711678 KW - Adolescent KW - Adult KW - Aged KW - Aged, 80 and over KW - Aging KW - Bromodeoxyuridine KW - Cell Cycle KW - Cell Division KW - Cells, Cultured KW - Child KW - Child, Preschool KW - Endothelium, Corneal KW - Fibroblast Growth Factors KW - Fluorescent Antibody Technique, Indirect KW - Humans KW - Infant KW - Ki-67 Antigen KW - Kinetics KW - Microscopy, Confocal KW - Middle Aged ER - TY - JOUR TI - 8-hydroxy-2' -deoxyguanosine (8-OHdG): A critical biomarker of oxidative stress and carcinogenesis AU - Valavanidis, Athanasios AU - Vlachogianni, Thomais AU - Fiotakis, Constantinos T2 - Journal of Environmental Science and Health. Part C, Environmental Carcinogenesis & Ecotoxicology Reviews AB - There is extensive experimental evidence that oxidative damage permanently occurs to lipids of cellular membranes, proteins, and DNA. In nuclear and mitochondrial DNA, 8-hydroxy-2' -deoxyguanosine (8-OHdG) or 8-oxo-7,8-dihydro-2' -deoxyguanosine (8-oxodG) is one of the predominant forms of free radical-induced oxidative lesions, and has therefore been widely used as a biomarker for oxidative stress and carcinogenesis. Studies showed that urinary 8-OHdG is a good biomarker for risk assessment of various cancers and degenerative diseases. The most widely used method of quantitative analysis is high-performance liquid chromatography (HPLC) with electrochemical detection (EC), gas chromatography-mass spectrometry (GC-MS), and HPLC tandem mass spectrometry. In order to resolve the methodological problems encountered in measuring quantitatively 8-OHdG, the European Standards Committee for Oxidative DNA Damage was set up in 1997 to resolve the artifactual oxidation problems during the procedures of isolation and purification of oxidative DNA products. The biomarker 8-OHdG or 8-oxodG has been a pivotal marker for measuring the effect of endogenous oxidative damage to DNA and as a factor of initiation and promotion of carcinogenesis. The biomarker has been used to estimate the DNA damage in humans after exposure to cancer-causing agents, such as tobacco smoke, asbestos fibers, heavy metals, and polycyclic aromatic hydrocarbons. In recent years, 8-OHdG has been used widely in many studies not only as a biomarker for the measurement of endogenous oxidative DNA damage but also as a risk factor for many diseases including cancer. DA - 2009/04// PY - 2009 DO - 10.1080/10590500902885684 DP - PubMed VL - 27 IS - 2 SP - 120 EP - 139 J2 - J Environ Sci Health C Environ Carcinog Ecotoxicol Rev LA - eng SN - 1532-4095 ST - 8-hydroxy-2' -deoxyguanosine (8-OHdG) L1 - https://www.reanimatology.com/rmt/article/download/1409/841 L2 - http://www.ncbi.nlm.nih.gov/pubmed/19412858 KW - Biomarkers KW - Carcinogens, Environmental KW - Cocarcinogenesis KW - Deoxyguanosine KW - DNA Damage KW - Environmental Exposure KW - Humans KW - Mutagenesis KW - Neoplasms KW - Oxidation-Reduction KW - Oxidative Stress KW - Reactive Oxygen Species KW - Risk Factors ER - TY - JOUR TI - Relationship among Oxidative Stress, DNA Damage, and Proliferative Capacity in Human Corneal Endothelium AU - Joyce, Nancy C. AU - Zhu, Cheng C. AU - Harris, Deshea L. T2 - Investigative Ophthalmology & Visual Science DA - 2009/05/01/ PY - 2009 DO - 10.1167/iovs.08-3007 DP - iovs.arvojournals.org VL - 50 IS - 5 SP - 2116 EP - 2122 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - https://iovs.arvojournals.org/article.aspx?articleid=2126584 Y2 - 2018/11/15/04:08:10 L1 - https://iovs.arvojournals.org/data/journals/iovs/932959/z7g00509002116.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2126584 ER - TY - ELEC TI - Slack, Slick, and Sodium-Activated Potassium Channels AU - Kaczmarek, Leonard K. T2 - International Scholarly Research Notices AB - The Slack and Slick genes encode potassium channels that are very widely expressed in the central nervous system. These channels are activated by elevations in intracellular sodium, such as those that occur during trains of one or more action potentials, or following activation of nonselective cationic neurotransmitter receptors such as AMPA receptors. This review covers the cellular and molecular properties of Slack and Slick channels and compares them with findings on the properties of sodium-activated potassium currents (termed KNa currents) in native neurons. Human mutations in Slack channels produce extremely severe defects in learning and development, suggesting that KNa channels play a central role in neuronal plasticity and intellectual function. DA - 2013/// PY - 2013 LA - en M3 - Research article UR - https://www.hindawi.com/journals/isrn/2013/354262/ Y2 - 2018/11/05/04:27:01 L1 - http://downloads.hindawi.com/archive/2013/354262.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/24319675 L4 - https://www.hindawi.com/journals/isrn/2013/354262/#B89 ER - TY - JOUR TI - A Na+- and Cl−-activated K+ Channel in the Thick Ascending Limb of Mouse Kidney AU - Paulais, Marc AU - Lachheb, Sahran AU - Teulon, Jacques T2 - The Journal of General Physiology AB - This study investigates the presence and properties of Na+-activated K+ (KNa) channels in epithelial renal cells. Using real-time PCR on mouse microdissected nephron segments, we show that Slo2.2 mRNA, which encodes for the KNa channels of excitable cells, is expressed in the medullary and cortical thick ascending limbs of Henle's loop, but not in the other parts of the nephron. Patch-clamp analysis revealed the presence of a high conductance K+ channel in the basolateral membrane of both the medullary and cortical thick ascending limbs. This channel was highly K+ selective (PK/PNa ∼ 20), its conductance ranged from 140 to 180 pS with subconductance levels, and its current/voltage relationship displayed intermediate, Na+-dependent, inward rectification. Internal Na+ and Cl− activated the channel with 50% effective concentrations (EC50) and Hill coefficients (nH) of 30 ± 1 mM and 3.9 ± 0.5 for internal Na+, and 35 ± 10 mM and 1.3 ± 0.25 for internal Cl−. Channel activity was unaltered by internal ATP (2 mM) and by internal pH, but clearly decreased when internal free Ca2+ concentration increased. This is the first demonstration of the presence in the epithelial cell membrane of a functional, Na+-activated, large-conductance K+ channel that closely resembles native KNa channels of excitable cells. This Slo2.2 type, Na+- and Cl−-activated K+ channel is primarily located in the thick ascending limb, a major renal site of transcellular NaCl reabsorption. DA - 2006/02/01/ PY - 2006 DO - 10.1085/jgp.200509360 DP - jgp.rupress.org VL - 127 IS - 2 SP - 205 EP - 215 LA - en SN - 0022-1295, 1540-7748 UR - http://jgp.rupress.org/content/127/2/205 Y2 - 2018/11/05/04:22:14 L1 - http://jgp.rupress.org/content/127/2/205.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/16446508 L2 - http://jgp.rupress.org/content/127/2/205 ER - TY - JOUR TI - An intermediate-conductance Ca2+-activated K+ channel is important for secretion in pancreatic duct cells AU - Hayashi, Mikio AU - Wang, Jing AU - Hede, Susanne E. AU - Novak, Ivana T2 - American Journal of Physiology. Cell Physiology AB - Potassium channels play a vital role in maintaining the membrane potential and the driving force for anion secretion in epithelia. In pancreatic ducts, which secrete bicarbonate-rich fluid, the identity of K(+) channels has not been extensively investigated. In this study, we investigated the molecular basis of functional K(+) channels in rodent and human pancreatic ducts (Capan-1, PANC-1, and CFPAC-1) using molecular and electrophysiological techniques. RT-PCR analysis revealed mRNAs for KCNQ1, KCNH2, KCNH5, KCNT1, and KCNT2, as well as KCNN4 coding for the following channels: KVLQT1; HERG; EAG2; Slack; Slick; and an intermediate-conductance Ca(2+)-activated K(+) (IK) channel (K(Ca)3.1). The following functional studies were focused on the IK channel. 5,6-Dichloro-1-ethyl-1,3-dihydro-2H-benzimidazole-2-one (DC-EBIO), an activator of IK channel, increased equivalent short-circuit current (I(sc)) in Capan-1 monolayer, consistent with a secretory response. Clotrimazole, a blocker of IK channel, inhibited I(sc). IK channel blockers depolarized the membrane potential of cells in microperfused ducts dissected from rodent pancreas. Cell-attached patch-clamp single-channel recordings revealed IK channels with an average conductance of 80 pS in freshly isolated rodent duct cells. These results indicated that the IK channels may, at least in part, be involved in setting the resting membrane potential. Furthermore, the IK channels are involved in anion and potassium transport in stimulated pancreatic ducts. DA - 2012/07/15/ PY - 2012 DO - 10.1152/ajpcell.00089.2012 DP - PubMed VL - 303 IS - 2 SP - C151 EP - 159 J2 - Am. J. Physiol., Cell Physiol. LA - eng SN - 1522-1563 L2 - http://www.ncbi.nlm.nih.gov/pubmed/22555847 KW - Animals KW - Cells, Cultured KW - Female KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Male KW - Membrane Potentials KW - Mice KW - Mice, Inbred BALB C KW - Mice, Inbred C57BL KW - Pancreatic Ducts KW - Potassium Channel Blockers KW - Rats KW - Rats, Wistar ER - TY - JOUR TI - The Drosophila sterile-20 kinase slik controls cell proliferation and apoptosis during imaginal disc development AU - Hipfner, David R. AU - Cohen, Stephen M. T2 - PLoS biology AB - Cell proliferation and programmed cell death are closely controlled during animal development. Proliferative stimuli generally also induce apoptosis, and anti-apoptotic factors are required to allow net cell proliferation. Genetic studies in Drosophila have led to identification of a number of genes that control both processes, providing new insights into the mechanisms that coordinate cell growth, proliferation, and death during development and that fail to do so in diseases of cell proliferation. We present evidence that the Drosophila Sterile-20 kinase Slik promotes cell proliferation and controls cell survival. At normal levels, Slik provides survival cues that prevent apoptosis. Cells deprived of Slik activity can grow, divide, and differentiate, but have an intrinsic survival defect and undergo apoptosis even under conditions in which they are not competing with normal cells for survival cues. Like some oncogenes, excess Slik activity stimulates cell proliferation, but this is compensated for by increased cell death. Tumor-like tissue overgrowth results when apoptosis is prevented. We present evidence that Slik acts via Raf, but not via the canonical ERK pathway. Activation of Raf can compensate for the lack of Slik and support cell survival, but activation of ERK cannot. We suggest that Slik mediates growth and survival cues to promote cell proliferation and control cell survival during Drosophila development. DA - 2003/11// PY - 2003 DO - 10.1371/journal.pbio.0000035 DP - PubMed VL - 1 IS - 2 SP - E35 J2 - PLoS Biol. LA - eng SN - 1545-7885 L1 - https://journals.plos.org/plosbiology/article/file?id=10.1371/journal.pbio.0000035&type=printable L2 - http://www.ncbi.nlm.nih.gov/pubmed/14624240 KW - Alleles KW - Animals KW - Apoptosis KW - Cell Differentiation KW - Cell Lineage KW - Cell Proliferation KW - Cell Survival KW - Drosophila melanogaster KW - Drosophila Proteins KW - Enzyme Activation KW - Extracellular Signal-Regulated MAP Kinases KW - Gene Expression Regulation, Developmental KW - Genotype KW - Immunoprecipitation KW - Inhibitor of Apoptosis Proteins KW - MAP Kinase Kinase 4 KW - Models, Genetic KW - Molecular Sequence Data KW - Mutation KW - Phenotype KW - Protein Binding KW - Protein-Serine-Threonine Kinases KW - Proto-Oncogene Proteins c-raf KW - RNA, Messenger KW - Transgenes KW - Wings, Animal ER - TY - JOUR TI - KCa2 channels activation prevents [Ca2+]i deregulation and reduces neuronal death following glutamate toxicity and cerebral ischemia AU - Dolga, A M AU - Terpolilli, N AU - Kepura, F AU - Nijholt, I M AU - Knaus, H-G AU - D'Orsi, B AU - Prehn, J H M AU - Eisel, U L M AU - Plant, T AU - Plesnila, N AU - Culmsee, C T2 - Cell Death & Disease AB - Exacerbated activation of glutamate receptor-coupled calcium channels and subsequent increase in intracellular calcium ([Ca2+]i) are established hallmarks of neuronal cell death in acute and chronic neurological diseases. Here we show that pathological [Ca2+]i deregulation occurring after glutamate receptor stimulation is effectively modulated by small conductance calcium-activated potassium (KCa2) channels. We found that neuronal excitotoxicity was associated with a rapid downregulation of KCa2.2 channels within 3 h after the onset of glutamate exposure. Activation of KCa2 channels preserved KCa2 expression and significantly reduced pathological increases in [Ca2+]i providing robust neuroprotection in vitro and in vivo. These data suggest a critical role for KCa2 channels in excitotoxic neuronal cell death and propose their activation as potential therapeutic strategy for the treatment of acute and chronic neurodegenerative disorders. DA - 2011/04// PY - 2011 DO - 10.1038/cddis.2011.30 DP - PubMed Central VL - 2 IS - 4 SP - e147 J2 - Cell Death Dis SN - 2041-4889 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3122061/ Y2 - 2018/11/05/03:17:25 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3122061/pdf/cddis201130a.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3122061/ ER - TY - JOUR TI - Laminar shear stress upregulates endothelial Ca²⁺-activated K⁺ channels KCa2.3 and KCa3.1 via a Ca²⁺/calmodulin-dependent protein kinase kinase/Akt/p300 cascade AU - Takai, Jun AU - Santu, Alexandra AU - Zheng, Haifeng AU - Koh, Sang Don AU - Ohta, Masanori AU - Filimban, Linda M. AU - Lemaître, Vincent AU - Teraoka, Ryutaro AU - Jo, Hanjoong AU - Miura, Hiroto T2 - American Journal of Physiology. Heart and Circulatory Physiology AB - In endothelial cells (ECs), Ca²⁺-activated K⁺ channels KCa2.3 and KCa3.1 play a crucial role in the regulation of arterial tone via producing NO and endothelium-derived hyperpolarizing factors. Since a rise in intracellular Ca²⁺ levels and activation of p300 histone acetyltransferase are early EC responses to laminar shear stress (LS) for the transcriptional activation of genes, we examined the role of Ca²⁺/calmodulin-dependent kinase kinase (CaMKK), the most upstream element of a Ca²⁺/calmodulin-kinase cascade, and p300 in LS-dependent regulation of KCa2.3 and KCa3.1 in ECs. Exposure to LS (15 dyn/cm²) for 24 h markedly increased KCa2.3 and KCa3.1 mRNA expression in cultured human coronary artery ECs (3.2 ± 0.4 and 45 ± 10 fold increase, respectively; P < 0.05 vs. static condition; n = 8-30), whereas oscillatory shear (OS; ± 5 dyn/cm² × 1 Hz) moderately increased KCa3.1 but did not affect KCa2.3. Expression of KCa2.1 and KCa2.2 was suppressed under both LS and OS conditions, whereas KCa1.1 was slightly elevated in LS and unchanged in OS. Inhibition of CaMKK attenuated LS-induced increases in the expression and channel activity of KCa2.3 and KCa3.1, and in phosphorylation of Akt (Ser473) and p300 (Ser1834). Inhibition of Akt abolished the upregulation of these channels by diminishing p300 phosphorylation. Consistently, disruption of the interaction of p300 with transcription factors eliminated the induction of these channels. Thus a CaMKK/Akt/p300 cascade plays an important role in LS-dependent induction of KCa2.3 and KCa3.1 expression, thereby regulating EC function and adaptation to hemodynamic changes. DA - 2013/08/15/ PY - 2013 DO - 10.1152/ajpheart.00642.2012 DP - PubMed VL - 305 IS - 4 SP - H484 EP - 493 J2 - Am. J. Physiol. Heart Circ. Physiol. LA - eng SN - 1522-1539 L1 - https://www.physiology.org/doi/pdf/10.1152/ajpheart.00642.2012 L2 - http://www.ncbi.nlm.nih.gov/pubmed/23792675 KW - Adaptation, Physiological KW - Ca2+-dependent signaling KW - Calcium-Calmodulin-Dependent Protein Kinase Kinase KW - Cells, Cultured KW - circulation KW - E1A-Associated p300 Protein KW - Endothelial Cells KW - endothelial function KW - Enzyme Activation KW - Hemodynamics KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - ion channels KW - Mechanotransduction, Cellular KW - Membrane Potentials KW - Phosphorylation KW - Protein Kinase Inhibitors KW - Proto-Oncogene Proteins c-akt KW - RNA, Messenger KW - Small-Conductance Calcium-Activated Potassium Channels KW - Stress, Mechanical KW - Time Factors KW - Up-Regulation ER - TY - JOUR TI - Functional KCa1.1 channels are crucial for regulating the proliferation, migration and differentiation of human primary skeletal myoblasts AU - Tajhya, Rajeev B. AU - Hu, Xueyou AU - Tanner, Mark R. AU - Huq, Redwan AU - Kongchan, Natee AU - Neilson, Joel R. AU - Rodney, George G. AU - Horrigan, Frank T. AU - Timchenko, Lubov T. AU - Beeton, Christine T2 - Cell Death & Disease AB - Myoblasts are mononucleated precursors of myofibers; they persist in mature skeletal muscles for growth and regeneration post injury. During myotonic dystrophy type 1 (DM1), a complex autosomal-dominant neuromuscular disease, the differentiation of skeletal myoblasts into functional myotubes is impaired, resulting in muscle wasting and weakness. The mechanisms leading to this altered differentiation are not fully understood. Here, we demonstrate that the calcium- and voltage-dependent potassium channel, KCa1.1 (BK, Slo1, KCNMA1), regulates myoblast proliferation, migration, and fusion. We also show a loss of plasma membrane expression of the pore-forming α subunit of KCa1.1 in DM1 myoblasts. Inhibiting the function of KCa1.1 in healthy myoblasts induced an increase in cytosolic calcium levels and altered nuclear factor kappa B (NFκB) levels without affecting cell survival. In these normal cells, KCa1.1 block resulted in enhanced proliferation and decreased matrix metalloproteinase secretion, migration, and myotube fusion, phenotypes all observed in DM1 myoblasts and associated with disease pathogenesis. In contrast, introducing functional KCa1.1 α-subunits into DM1 myoblasts normalized their proliferation and rescued expression of the late myogenic marker Mef2. Our results identify KCa1.1 channels as crucial regulators of skeletal myogenesis and suggest these channels as novel therapeutic targets in DM1. DA - 2016//10/20 PY - 2016 DO - 10.1038/cddis.2016.324 DP - PubMed VL - 7 IS - 10 SP - e2426 J2 - Cell Death Dis LA - eng SN - 2041-4889 L1 - https://www.nature.com/articles/cddis2016324.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/27763639 KW - Calcium KW - Cell Differentiation KW - Cell Fusion KW - Cell Membrane KW - Cell Movement KW - Cell Proliferation KW - Cells, Cultured KW - Humans KW - Intracellular Space KW - Large-Conductance Calcium-Activated Potassium Channel alpha Subunits KW - Matrix Metalloproteinase 2 KW - Muscle Fibers, Skeletal KW - Myoblasts, Skeletal KW - Myotonic Dystrophy KW - NF-kappa B ER - TY - JOUR TI - The SK3/KCa2.3 potassium channel is a new cellular target for edelfosine AU - Potier, M AU - Chantome, A AU - Joulin, V AU - Girault, A AU - Roger, S AU - Besson, P AU - Jourdan, M-L AU - LeGuennec, J-Y AU - Bougnoux, P AU - Vandier, C T2 - British Journal of Pharmacology AB - BACKGROUND AND PURPOSE The 1-O-octadecyl-2-O-methyl-sn-glycero-3-phosphocholine (edelfosine) is an ether-linked phospholipid with promising anti-cancer properties but some side effects that preclude its full clinical therapeutic exploitation. We hypothesized that this lipid could interact with plasma membrane ion channels and modulate their function. EXPERIMENTAL APPROACH Using cell migration-proliferation assays, patch clamp, spectrofluorimetry and 125I-Apamin binding experiments, we studied the effects of edelfosine on the migration of breast cancer MDA-MB-435s cells, mediated by the small conductance Ca2+-activated K+ channel, SK3/KCa2.3. KEY RESULTS Edelfosine (1 µM) caused plasma membrane depolarization by substantially inhibiting activity of SK3/KCa2.3 channels, which we had previously demonstrated to play an important role in cancer cell migration. Edelfosine did not inhibit 125I-Apamin binding to this SKCa channel; rather, it reduced the calcium sensitivity of SK3/KCa2.3 channel and dramatically decreased intracellular Ca2+ concentration, probably by insertion in the plasma membrane, as suggested by proteinase K experiments. Edelfosine reduced cell migration to the same extent as known SKCa channel blockers. In contrast, K+ channel openers prevented edelfosine-induced anti-migratory effects. SK3 protein knockdown decreased cell migration and totally abolished the effect of edelfosine on MDA-MB-435s cell migration. In contrast, transient expression of SK3/KCa2.3 protein in a SK3/KCa2.3-deficient cell line increased cell migration and made these cells responsive to edelfosine. CONCLUSIONS AND IMPLICATIONS Our data clearly establish edelfosine as an inhibitor of cancer cell migration by acting on SK3/KCa2.3 channels and provide insights into the future development of a new class of migration-targeted, anti-cancer agents. DA - 2011/01// PY - 2011 DO - 10.1111/j.1476-5381.2010.01044.x DP - PubMed Central VL - 162 IS - 2 SP - 464 EP - 479 J2 - Br J Pharmacol SN - 0007-1188 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3031066/ Y2 - 2018/11/05/02:33:22 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3031066/pdf/bph0162-0464.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3031066/ ER - TY - JOUR TI - Role of Ion Channels and Transporters in Cell Migration AU - Schwab, Albrecht AU - Fabian, Anke AU - Hanley, Peter J. AU - Stock, Christian T2 - Physiological Reviews AB - Cell motility is central to tissue homeostasis in health and disease, and there is hardly any cell in the body that is not motile at a given point in its life cycle. Important physiological processes intimately related to the ability of the respective cells to migrate include embryogenesis, immune defense, angiogenesis, and wound healing. On the other side, migration is associated with life-threatening pathologies such as tumor metastases and atherosclerosis. Research from the last ∼15 years revealed that ion channels and transporters are indispensable components of the cellular migration apparatus. After presenting general principles by which transport proteins affect cell migration, we will discuss systematically the role of channels and transporters involved in cell migration. DA - 2012/10/01/ PY - 2012 DO - 10.1152/physrev.00018.2011 DP - physiology.org (Atypon) VL - 92 IS - 4 SP - 1865 EP - 1913 J2 - Physiological Reviews SN - 0031-9333 UR - https://www.physiology.org/doi/full/10.1152/physrev.00018.2011 Y2 - 2018/11/04/22:04:35 L1 - https://www.physiology.org/doi/pdf/10.1152/physrev.00018.2011 L2 - https://www.physiology.org/doi/full/10.1152/physrev.00018.2011 ER - TY - JOUR TI - K+ channels and cell cycle progression in tumor cells AU - Ouadid-Ahidouch, Halima AU - Ahidouch, Ahmed T2 - Frontiers in Physiology AB - K+ ions play a major role in many cellular processes. The deregulation of K+ signaling is associated with a variety of diseases such as hypertension, atherosclerosis, or diabetes. K+ ions are important for setting the membrane potential, the driving force for Ca2+ influx, and regulate volume of growing cells. Moreover, it is increasingly recognized that K+ channels control cell proliferation through a novel signaling mechanisms triggered and modulated independently of ion fluxes. In cancer, aberrant expression, regulation and/or sublocalization of K+ channels can alter the downstream signals that converge on the cell cycle machinery. Various K+ channels are involved in cell cycle progression and are needed only at particular stages of the cell cycle. Consistent with this idea, the expression of Eag1 and HERG channels fluctuate along the cell cycle. Despite of acquired knowledge, our understanding of K+ channels functioning in cancer cells requires further studies. These include identifying the molecular mechanisms controlling the cell cycle machinery. By understanding how K+ channels regulate cell cycle progression in cancer cells, we will gain insights into how cancer cells subvert the need for K+ signal and its downstream targets to proliferate. DA - 2013/08/20/ PY - 2013 DO - 10.3389/fphys.2013.00220 DP - PubMed Central VL - 4 J2 - Front Physiol SN - 1664-042X UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3747328/ Y2 - 2018/11/04/21:48:41 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3747328/pdf/fphys-04-00220.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3747328/ ER - TY - JOUR TI - Bovine and Mouse SLO3 K+ Channels AU - Santi, Celia M. AU - Butler, Alice AU - Kuhn, Julia AU - Wei, Aguan AU - Salkoff, Lawrence T2 - The Journal of Biological Chemistry AB - The slo3 gene encodes a K+ channel found only in mammalian testis. This is in contrast to slo1, which is expressed in many tissues. Genes pertaining to male reproduction, especially those involved in sperm production, evolve morphologically and functionally much faster than their nonsexual counterparts. A comparison of SLO3 channel amino acid sequences from several species revealed a high degree of structural divergence relative to their SLO1 channel paralogues. To reveal any biophysical differences accompanying this rapid structural divergence, we analyzed the functional properties of SLO3 channels from two species, bovine and mouse. We observed several functional differences including voltage range of activation, kinetics, and pH sensitivity. Although SLO3 channel proteins from these two species lack conservation in many structural regions, we found that the first two of these three functional differences map to the same loop structure in their RCK1 (regulator of K+ conductance 1) domain, which links the intermediate RCK1 subdomain to the C-terminal subdomain. We found that small structural changes in this region produce major changes in the voltage range of activation and kinetics. This rapidly evolving loop peptide shows the greatest length and sequence polymorphisms within RCK1 domains from many different species. In SLO3 channels this region may permit evolutionary changes that tune the gating properties in different species. DA - 2009/08/07/ PY - 2009 DO - 10.1074/jbc.M109.015040 DP - PubMed Central VL - 284 IS - 32 SP - 21589 EP - 21598 J2 - J Biol Chem SN - 0021-9258 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2755883/ Y2 - 2018/11/04/17:56:39 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2755883/pdf/zbc21589.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2755883/ ER - TY - JOUR TI - KCa3.1 as an Effective Target for Inhibition of Growth and Progression of Intrahepatic Cholangiocarcinoma AU - Song, Penghong AU - Du, Yehui AU - Song, Wenfeng AU - Chen, Hao AU - Xuan, Zefeng AU - Zhao, Long AU - Chen, Jun AU - Chen, Jian AU - Guo, Danjing AU - Jin, Cheng AU - Zhao, Yongchao AU - Tuo, Biguang AU - Zheng, Shusen T2 - Journal of Cancer AB - Background: Intrahepatic cholangiocarcinoma (ICC) is a high malignant tumor arising from the bile ducts in the liver with a poor prognosis. As current molecular targeted therapies and systemic chemotherapies had limited success in ICC, novel therapeutic targets are needed. In this study, we attempted to investigate the expression and the role of the intermediate conductance calcium-activated potassium channel (KCa3.1) in ICC., Methods: The expression levels of KCa3.1 channel were measured in 81 resected ICC tumor specimens and the clinicopathological significance of these levels were determined. KCa3.1 channel inhibitor and siRNA were used to study the role of KCa3.1 in proliferation, migration, and invasion of ICC cell lines. The effect of KCa3.1 channel blockade on tumor growth in vivo was also studied using xenograft model in nude mice., Results: The protein expression of KCa3.1 channel was upregulated in ICC tissues and was correlated with age, lymph node metastasis and TNM stage. And high KCa3.1 expression indicated a worse prognosis in ICC patients. Blocking KCa3.1 channel with a specific inhibitor TRAM-34 reduced the proliferation and invasion of ICC cells. Knockdown of KCa3.1 could achieve the same effects through decreasing NF-κB activation. Further in vivo studies demonstrated that KCa3.1 channel blockade suppressed ICC tumor growth., Conclusions: Our observations suggested KCa3.1 might be a promising novel therapeutic target in intrahepatic cholangiocarcinoma. DA - 2017/06/03/ PY - 2017 DO - 10.7150/jca.18697 DP - PubMed Central VL - 8 IS - 9 SP - 1568 EP - 1578 J2 - J Cancer SN - 1837-9664 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5535712/ Y2 - 2018/11/04/17:46:18 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5535712/pdf/jcav08p1568.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5535712/ ER - TY - JOUR TI - KV1.3: A new therapeutic target to control vascular smooth muscle cell proliferation AU - Jackson, William F. T2 - Arteriosclerosis, thrombosis, and vascular biology DA - 2010/06// PY - 2010 DO - 10.1161/ATVBAHA.110.206565 DP - PubMed Central VL - 30 IS - 6 SP - 1073 EP - 1074 J2 - Arterioscler Thromb Vasc Biol SN - 1079-5642 ST - KV1.3 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2891047/ Y2 - 2018/11/04/05:42:24 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2891047/pdf/nihms203358.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2891047/ ER - TY - JOUR TI - cDNA cloning and functional characterization of the mouse Ca2+-gated K+ channel, mIK1. Roles in regulatory volume decrease and erythroid differentiation AU - Vandorpe, D. H. AU - Shmukler, B. E. AU - Jiang, L. AU - Lim, B. AU - Maylie, J. AU - Adelman, J. P. AU - de Franceschi, L. AU - Cappellini, M. D. AU - Brugnara, C. AU - Alper, S. L. T2 - The Journal of Biological Chemistry AB - We have cloned from murine erythroleukemia (MEL) cells, thymus, and stomach the cDNA encoding the Ca2+-gated K+ (KCa) channel, mIK1, the mouse homolog of hIK1 (Ishii, T. M., Silvia, C., Hirschberg, B., Bond, C. T., Adelman, J. P., and Maylie, J. (1997) Proc. Natl. Acad. Sci.(U. S. A. 94, 11651-11656). mIK1 mRNA was detected at varied levels in many tissue types. mIK1 KCa channel activity expressed in Xenopus oocytes closely resembled the Kca of red cells (Gardos channel) and MEL cells in its single channel conductance, lack of voltage-sensitivity of activation, inward rectification, and Ca2+ concentration dependence. mIK1 also resembled the erythroid channel in its pharmacological properties, mediating whole cell and unitary currents sensitive to low nM concentrations of both clotrimazole (CLT) and its des-imidazolyl metabolite, 2-chlorophenyl-bisphenyl-methanol, and to low nM concentrations of iodocharybdotoxin. Whereas control oocytes subjected to hypotonic swelling remained swollen, mIK1 expression conferred on oocytes a novel, Ca2+-dependent, CLT-sensitive regulatory volume decrease response. Hypotonic swelling of voltage-clamped mIK1-expressing oocytes increased outward currents that were Ca2+-dependent, CLT-sensitive, and reversed near the K+ equilibrium potential. mIK1 mRNA levels in ES cells increased steadily during erythroid differentiation in culture, in contrast to other KCa mRNAs examined. Low nanomolar concentrations of CLT inhibited proliferation and erythroid differentiation of peripheral blood stem cells in liquid culture. DA - 1998/08/21/ PY - 1998 DP - PubMed VL - 273 IS - 34 SP - 21542 EP - 21553 J2 - J. Biol. Chem. LA - eng SN - 0021-9258 L2 - http://www.ncbi.nlm.nih.gov/pubmed/9705284 KW - Animals KW - Calcium KW - Cell Differentiation KW - Cell Size KW - Cloning, Molecular KW - Clotrimazole KW - DNA, Complementary KW - Erythroid Precursor Cells KW - Friend murine leukemia virus KW - Glycosylation KW - Hypotonic Solutions KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Ion Channel Gating KW - Leukemia, Erythroblastic, Acute KW - Mice KW - Molecular Sequence Data KW - Potassium Channels KW - Potassium Channels, Calcium-Activated KW - RNA, Messenger KW - Tumor Cells, Cultured KW - Xenopus ER - TY - JOUR TI - K+ channels as targets for specific immunomodulation AU - Chandy, K. George AU - Wulff, Heike AU - Beeton, Christine AU - Pennington, Michael AU - Gutman, George A. AU - Cahalan, Michael D. T2 - Trends in Pharmacological Sciences AB - The voltage-gated Kv1.3 channel and the Ca(2+)-activated IKCa1 K(+) channel are expressed in T cells in a distinct pattern that depends on the state of lymphocyte activation and differentiation. The channel phenotype changes during the progression from the resting to the activated cell state and from naïve to effector memory cells, affording promise for specific immunomodulatory actions of K(+) channel blockers. In this article, we review the functional roles of these channels in both naïve cells and memory cells, describe the development of selective inhibitors of Kv1.3 and IKCa1 channels, and provide a rationale for the potential therapeutic use of these inhibitors in immunological disorders. DA - 2004/05// PY - 2004 DO - 10.1016/j.tips.2004.03.010 DP - PubMed VL - 25 IS - 5 SP - 280 EP - 289 J2 - Trends Pharmacol. Sci. LA - eng SN - 0165-6147 L1 - https://europepmc.org/articles/pmc2749963?pdf=render L2 - http://www.ncbi.nlm.nih.gov/pubmed/15120495 KW - Adjuvants, Immunologic KW - Calcium Channel Blockers KW - Calcium Channels KW - Humans KW - Lymphocytes KW - Potassium Channel Blockers KW - Potassium Channels KW - T-Lymphocytes ER - TY - JOUR TI - International Union of Pharmacology. LII. Nomenclature and Molecular Relationships of Calcium-Activated Potassium Channels AU - Wei, Aguan D. AU - Gutman, George A. AU - Aldrich, Richard AU - Chandy, K. George AU - Grissmer, Stephan AU - Wulff, Heike T2 - Pharmacological Reviews AB - The second major group of six/seven transmembrane potassium-selective channels consists of the KCa channels (for reviews, see [Lingle, 2002][1]; [Magleby, 2003][2]; [Moczydlowski, 2004][3]; [Stocker, 2004][4]; [Cox, 2005][5]), and [Table 1][6] shows the International Union of Pharmacology (IUPHAR[1 DA - 2005/12/01/ PY - 2005 DO - 10.1124/pr.57.4.9 DP - pharmrev.aspetjournals.org VL - 57 IS - 4 SP - 463 EP - 472 J2 - Pharmacol Rev LA - en SN - 0031-6997, 1521-0081 UR - http://pharmrev.aspetjournals.org/content/57/4/463 Y2 - 2018/11/04/03:53:18 L1 - http://pharmrev.aspetjournals.org/content/57/4/463.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/16382103 L2 - http://pharmrev.aspetjournals.org/content/57/4/463 ER - TY - ELEC TI - International Union of Pharmacology. LII. Nomenclature and Molecular Relationships of Calcium-Activated Potassium Channels | Pharmacological Reviews UR - http://pharmrev.aspetjournals.org/content/57/4/463 Y2 - 2018/11/04/03:17:27 L2 - http://pharmrev.aspetjournals.org/content/57/4/463 ER - TY - JOUR TI - Functional Effects of Auxiliary β4-Subunit on Rat Large-Conductance Ca2+-Activated K+ Channel AU - Ha, Tal Soo AU - Heo, Moon-Sun AU - Park, Chul-Seung T2 - Biophysical Journal AB - Large-conductance calcium-activated potassium (BKCa) channels are composed of the pore-forming α-subunit and the auxiliary β-subunits. The β4-subunit is dominantly expressed in the mammalian central nervous system. To understand the physiological roles of the β4-subunit on the BKCa channel α-subunit (Slo), we isolated a full-length complementary DNA of rat β4-subunit (rβ4), expressed heterolgously in Xenopus oocytes, and investigated the detailed functional effects using electrophysiological means. When expressed together with rat Slo (rSlo), rβ4 profoundly altered the gating characteristics of the Slo channel. At a given concentration of intracellular Ca2+, rSlo/rβ4 channels were more sensitive to transmembrane voltage changes. The activation and deactivation rates of macroscopic currents were decreased in a Ca2+-dependent manner. The channel activation by Ca2+ became more cooperative by the coexpression of rβ4. Single-channel recordings showed that the increased Hill coefficient for Ca2+ was due to the changes in the open probability of the rSlo/rβ4 channel. Single BKCa channels composed of rSlo and rβ4 also exhibited slower kinetics for steady-state gating compared with rSlo channels. Dwell times of both open and closed events were significantly increased. Because BKCa channels are known to modulate neuroexcitability and the expression of the β4-subunit is highly concentrated in certain subregions of brain, the electrophysiological properties of individual neurons should be affected profoundly by the expression of this second subunit. DA - 2004/05/01/ PY - 2004 DO - 10.1016/S0006-3495(04)74339-8 DP - ScienceDirect VL - 86 IS - 5 SP - 2871 EP - 2882 J2 - Biophysical Journal SN - 0006-3495 UR - http://www.sciencedirect.com/science/article/pii/S0006349504743398 Y2 - 2018/11/04/03:04:15 L1 - https://ac.els-cdn.com/S0006349504743398/1-s2.0-S0006349504743398-main.pdf?_tid=c54f55e3-2d9b-48d1-8005-a167c96e2707&acdnat=1541300829_1a964e3a036630727e2dfcfc2ac848eb L2 - https://www.sciencedirect.com/science/article/pii/S0006349504743398 ER - TY - JOUR TI - KCa and Ca2+ channels: The complex thought AU - Guéguinou, Maxime AU - Chantôme, Aurélie AU - Fromont, Gaëlle AU - Bougnoux, Philippe AU - Vandier, Christophe AU - Potier-Cartereau, Marie T2 - Biochimica et Biophysica Acta (BBA) - Molecular Cell Research T3 - Calcium Signaling in Health and Disease AB - Potassium channels belong to the largest and the most diverse super-families of ion channels. Among them, Ca2+-activated K+ channels (KCa) comprise many members. Based on their single channel conductance they are divided into three subfamilies: big conductance (BKCa), intermediate conductance (IKCa) and small conductance (SKCa; SK1, SK2 and SK3). Ca2+ channels are divided into two main families, voltage gated/voltage dependent Ca2+ channels and non-voltage gated/voltage independent Ca2+ channels. Based on their electrophysiological and pharmacological properties and on the tissue where there are expressed, voltage gated Ca2+ channels (Cav) are divided into 5 families: T-type, L-type, N-type, P/Q-type and R-type Ca2+. Non-voltage gated Ca2+ channels comprise the TRP (TRPC, TRPV, TRPM, TRPA, TRPP, TRPML and TRPN) and Orai (Orai1 to Orai3) families and their partners STIM (STIM1 to STIM2). A depolarization is needed to activate voltage-gated Ca2+ channels while non-voltage gated Ca2+ channels are activated by Ca2+ depletion of the endoplasmic reticulum stores (SOCs) or by receptors (ROCs). These two Ca2+ channel families also control constitutive Ca2+ entries. For reducing the energy consumption and for the fine regulation of Ca2+, KCa and Ca2+ channels appear associated as complexes in excitable and non-excitable cells. Interestingly, there is now evidence that KCa–Ca2+ channel complexes are also found in cancer cells and contribute to cancer-associated functions such as cell proliferation, cell migration and the capacity to develop metastases. This article is part of a Special Issue entitled: Calcium signaling in health and disease. Guest Editors: Geert Bultynck, Jacques Haiech, Claus W. Heizmann, Joachim Krebs, and Marc Moreau. DA - 2014/10/01/ PY - 2014 DO - 10.1016/j.bbamcr.2014.02.019 DP - ScienceDirect VL - 1843 IS - 10 SP - 2322 EP - 2333 J2 - Biochimica et Biophysica Acta (BBA) - Molecular Cell Research SN - 0167-4889 ST - KCa and Ca2+ channels UR - http://www.sciencedirect.com/science/article/pii/S0167488914000834 Y2 - 2018/11/03/22:56:19 L1 - https://ac.els-cdn.com/S0167488914000834/1-s2.0-S0167488914000834-main.pdf?_tid=b0677825-00d0-4fb1-9f88-154aa1d8e64e&acdnat=1541285954_03afefc715172bcfc33d1217c0f531d0 L2 - https://www.sciencedirect.com/science/article/pii/S0167488914000834 KW - Ca channels KW - Cancer KW - KCa channels KW - Orai KW - SOC KW - TRP ER - TY - JOUR TI - Prevalence and incidence of type 1 diabetes in the world: a systematic review and meta-analysis AU - Mobasseri, Majid AU - Shirmohammadi, Masoud AU - Amiri, Tarlan AU - Vahed, Nafiseh AU - Hosseini Fard, Hossein AU - Ghojazadeh, Morteza T2 - Health Promotion Perspectives AB - Background: Diabetes is referred to a group of diseases characterized by high glucose levels in blood. It is caused by a deficiency in the production or function of insulin or both, which can occur because of different reasons, resulting in protein and lipid metabolic disorders. The aim of this study was to systematically review the prevalence and incidence of type 1 diabetes in the world. , Methods: A systematic search of resources was conducted to investigate the prevalence and incidence of type 1 diabetes in the world. The databases of Medline (via PubMed and Ovid),ProQuest, Scopus, and Web of Science from January 1980 to September 2019 were searched to locate English articles. The located articles were screened in multiple levels of title, abstract,and full-text and final studies that met the inclusion criteria were retrieved and included in the study. , Results: From 1202 located articles, 193 studies were included in this systematic review. The results of meta-analysis showed that the incidence of type 1 diabetes was 15 per 100,000 people and the prevalence was 9.5% (95% CI: 0.07 to 0.12) in the world, which was statistically significant. , Conclusion: According to the results, the incidence and prevalence of type 1 diabetes are increasing in the world. As a result, insulin will be difficult to access and afford, especially in underdeveloped and developing countries. DA - 2020/03/30/ PY - 2020 DO - 10.34172/hpp.2020.18 DP - PubMed Central VL - 10 IS - 2 SP - 98 EP - 115 J2 - Health Promot Perspect SN - 2228-6497 ST - Prevalence and incidence of type 1 diabetes in the world UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7146037/ Y2 - 2020/08/17/12:24:10 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7146037/pdf/hpp-10-98.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7146037/ ER - TY - JOUR TI - Inequalities in glycaemic control, hypoglycaemia and diabetic ketoacidosis according to socio-economic status and area-level deprivation in Type 1 diabetes mellitus: a systematic review AU - Lindner, L. M. E. AU - Rathmann, W. AU - Rosenbauer, J. T2 - Diabetic Medicine AB - Aim The aim of this systematic review was to examine the associations of individual-level as well as area-level socio-economic status and area-level deprivation with glycaemic control, hypoglycaemia and diabetic ketoacidosis in people with Type 1 diabetes mellitus. Methods Ovid MEDLINE was searched to identify relevant cohort, case-control or cross-sectional studies published between January 2000 and June 2015. Search results were screened by title, abstract and keywords to identify eligible publications. Decisions on inclusion or exclusion of full texts were made independently by two reviewers. The Newcastle-Ottawa Scale was used to estimate the methodological quality of included studies. Quality assessment and extracted data of included studies were synthesized narratively and reported according to the PRISMA statement. Results Literature search in Ovid MEDLINE identified 1345 eligible studies. Twenty studies matched our inclusion and exclusion criteria. Two articles were additionally identified through hand search. According to the Newcastle-Ottawa Scale, most of the studies were of average quality. Results on associations of socio-economic status and area-level deprivation with glycaemic control and hypoglycaemia were contradictory between studies. By contrast, lower socio-economic status and higher area-level deprivation were associated with a higher risk for diabetic ketoacidosis in all except one study. Conclusions Lower socio-economic status and higher area-level deprivation are associated with a higher risk of experiencing diabetic ketoacidosis in people with Type 1 diabetes mellitus. Access to care for socially deprived people needs to be expanded to overcome impairing effects on the course of the condition and to reduce healthcare disparities. DA - 2018/// PY - 2018 DO - 10.1111/dme.13519 DP - Wiley Online Library VL - 35 IS - 1 SP - 12 EP - 32 LA - en SN - 1464-5491 ST - Inequalities in glycaemic control, hypoglycaemia and diabetic ketoacidosis according to socio-economic status and area-level deprivation in Type 1 diabetes mellitus UR - https://onlinelibrary.wiley.com/doi/abs/10.1111/dme.13519 Y2 - 2020/08/17/13:14:29 L2 - https://onlinelibrary.wiley.com/doi/abs/10.1111/dme.13519 ER - TY - JOUR TI - Diabetic Retinopathy and Blindness: An Epidemiological Overview AU - Pandova, Maya Georgieva T2 - Visual Impairment and Blindness - What We Know and What We Have to Know AB - Prevalence of diabetes is rising worldwide. In the course of the last 20 years, blindness and low vision due to diabetic eye complications have increased in large regions in Eastern Europe, North Africa/Middle East, Asia, Latin America, and Oceania. The magnitude and trends of vision-threatening disease are presented. Systemic risk factors for progression to sight-threatening disease are reviewed. The impact of economic and cultural background on early diagnosis and adherence to treatment is highlighted. Current management of diabetic macular edema, proliferative diabetic retinopathy, neovascular glaucoma, and cataract surgery of diabetic patients is outlined, and its contribution to preventing vision loss is reviewed. DA - 2019/08/19/ PY - 2019 DO - 10.5772/intechopen.88756 DP - www.intechopen.com LA - en ST - Diabetic Retinopathy and Blindness UR - https://www.intechopen.com/online-first/diabetic-retinopathy-and-blindness-an-epidemiological-overview Y2 - 2020/08/17/13:17:43 L1 - https://www.intechopen.com/citation-pdf-url/68627 L2 - https://www.intechopen.com/online-first/diabetic-retinopathy-and-blindness-an-epidemiological-overview ER - TY - JOUR TI - Burden of Complications in U.S. Adults With Young-Onset Type 2 or Type 1 Diabetes AU - Fang, Michael AU - Echouffo-Tcheugui, Justin B. AU - Selvin, Elizabeth T2 - Diabetes Care AB - Young-onset type 2 diabetes has a more aggressive clinical course than type 2 diabetes that occurs at an older age (1). Accruing evidence suggests that young adults with type 2 diabetes have complication rates exceeding those of individuals of similar age with type 1 diabetes (1–3). However, prior studies have focused on select populations and the generalizability of their findings is not clear. To address this gap in the literature, we analyzed recent national data to characterize the prevalence of complications among U.S. adults with young-onset type 1 and type 2 diabetes. We pooled data from the 2016 and 2017 National Health Interview Survey (NHIS). The NHIS is the only representative U.S. study that collects self-reported information on types of diabetes. Participants reported whether they had ever been diagnosed with diabetes other than during pregnancy. Those with diagnosed diabetes reported the type of diabetes (type 1, type 2, other), age of diagnosis, and use of antidiabetes medication. Following past research, we defined young-onset type 2 diabetes as being diagnosed before age 40 (1). We defined young-onset type 1 diabetes using this same cut point for comparability. We classified … DA - 2020/04/01/ PY - 2020 DO - 10.2337/dc19-2394 DP - care.diabetesjournals.org VL - 43 IS - 4 SP - e47 EP - e49 LA - en SN - 0149-5992, 1935-5548 UR - https://care.diabetesjournals.org/content/43/4/e47 Y2 - 2020/08/17/14:00:48 L1 - https://care.diabetesjournals.org/content/diacare/43/4/e47.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/32029637 L2 - https://care.diabetesjournals.org/content/43/4/e47 ER - TY - JOUR TI - Ocular Associations of Diabetes Other Than Diabetic Retinopathy AU - Jeganathan, V. Swetha E. AU - Wang, Jie Jin AU - Wong, Tien Yin T2 - Diabetes Care DA - 2008/09// PY - 2008 DO - 10.2337/dc08-0342 DP - PubMed Central VL - 31 IS - 9 SP - 1905 EP - 1912 J2 - Diabetes Care SN - 0149-5992 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2518369/ Y2 - 2020/08/17/14:39:16 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2518369/pdf/1905.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2518369/ ER - TY - JOUR TI - The corneal endothelium AU - Tuft, S. J. AU - Coster, D. J. T2 - Eye AB - The endothelium is a monolayer of cells on the posterior corneal surface that transports water from the stroma into the anterior chamber. This movement of water counters a natural tendency for the stroma to swell and is necessary to maintain a transparent cornea. Embryologic studies, in particular the demonstration of the derivation of the endothelium from the neural crest, have provided insight into the factors that govern the response of this tissue to disease. In some species the endothelium can regenerate after injury, but in man cellular enlargement is the main mechanism of repair after cell loss. A clinical estimate of endothelial cell density and function is provided by specular microscopy, fluorophotometry and pachymetry. In this paper we review the development, structure and function of the corneal endothelium, and then consider the pathological processes that can affect this tissue. DA - 1990/05// PY - 1990 DO - 10.1038/eye.1990.53 DP - www.nature.com VL - 4 IS - 3 SP - 389 EP - 424 LA - en SN - 1476-5454 UR - https://www.nature.com/articles/eye199053 Y2 - 2020/08/19/23:08:22 L1 - https://www.nature.com/articles/eye199053.pdf L2 - https://www.nature.com/articles/eye199053#citeas ER - TY - ELEC TI - Cochrane Handbook for Systematic Reviews of Interventions LA - en UR - /handbook/current Y2 - 2020/09/08/17:55:35 L2 - https://training.cochrane.org/handbook/current ER - TY - JOUR TI - MaxiK channel and cell signalling AU - Toro, Ligia AU - Li, Min AU - Zhang, Zhu AU - Singh, Harpreet AU - Wu, Yong AU - Stefani, Enrico T2 - Pflugers Archiv : European journal of physiology AB - The large-conductance Ca2+- and voltage-activated K+ (MaxiK, BK, BKCa, Slo1, KCa1.1) channel role in cell signalling is becoming apparent as we learn how the channel interacts with a multiplicity of proteins not only at the plasma membrane but in intracellular organelles including the endoplasmic reticulum, nucleus and mitochondria. In this review, we focus on the interactions of MaxiK channels with seven transmembrane G-protein coupled receptors, and discuss information suggesting that the channel big C-terminus may act as nucleus of signalling molecules including kinases relevant for cell death and survival. Increasing evidence indicates that the channel is able to associate with a variety of receptors including β-adrenergic receptors, G-protein coupled estrogen receptors, acetylcholine receptors, thromboxane A2 receptors and angiotensin II receptors, which highlights the varied functions that the channel has (or may have) not only in regulating contraction/relaxation of muscle cells or neurotransmission in the brain but also in cell metabolism, proliferation, migration and gene expression. In line with this view, MaxiK channels have been implicated in obesity and in brain, prostate, and mammary cancers. A better understanding of the molecular mechanisms underlying or triggered by MaxiK channel abnormalities like overexpression in certain cancers may lead to new therapeutics to prevent devastating diseases. DA - 2014/05// PY - 2014 DO - 10.1007/s00424-013-1359-0 DP - PubMed Central VL - 466 IS - 5 SP - 875 EP - 886 J2 - Pflugers Arch SN - 0031-6768 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3969412/ Y2 - 2020/09/18/10:21:15 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3969412/pdf/nihms528308.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3969412/ ER - TY - JOUR TI - Association between corneal endothelial cell densities and elevated cytokine levels in the aqueous humor AU - Yagi-Yaguchi, Yukari AU - Yamaguchi, Takefumi AU - Higa, Kazunari AU - Suzuki, Terumasa AU - Aketa, Naohiko AU - Dogru, Murat AU - Satake, Yoshiyuki AU - Shimazaki, Jun T2 - Scientific Reports AB - Annual reduction rate of corneal endothelial cell density (ECD) varies among etiologies, however, the cause of chronic endothelial cell loss is still unknown. We recently reported the elevation of inflammatory cytokines in the aqueous humor (AqH) in eyes with bullous keratopathy and low ECD. To evaluate the association between ECD and aqueous cytokine levels, we collected a total of 157 AqH samples prospectively. The AqH levels of cytokines were measured and multivariate analyses were conducted to find the correlation between ECD, aqueous cytokine levels and clinical factors, such as number of previous intraocular surgeries and protein concentration in AqH. As a result, ECD was negatively correlated with specific cytokine levels, including IL-1α, IL-4, IL-13, MIP-1β, TNF-α and E-selectin (all P < 0.05). The aqueous cytokine levels showed different correlations with these clinical factors; the number of previous intraocular surgeries was associated with all cytokines except MIP-1α. The AqH protein concentration and the status of intraocular lens showed similar patterns of elevation of IL-1α, IL-4, IL-6, IL-8, IL-10, IL-13, IL-17A, MIP-1β, MCP-1, E-selectin, P-selectin and sICAM-1. In conclusion, elevation of AqH cytokine levels was associated with reduced ECDs. AqH cytokine levels showed significant correlations with clinical factors associated with low ECDs. DA - 2017/10/19/ PY - 2017 DO - 10.1038/s41598-017-14131-3 DP - www.nature.com VL - 7 IS - 1 SP - 13603 LA - en SN - 2045-2322 UR - https://www.nature.com/articles/s41598-017-14131-3 Y2 - 2020/09/18/10:44:14 L1 - https://www.nature.com/articles/s41598-017-14131-3.pdf L2 - https://www.nature.com/articles/s41598-017-14131-3 ER - TY - JOUR TI - Association between corneal endothelial cell densities and elevated cytokine levels in the aqueous humor AU - Yagi-Yaguchi, Yukari AU - Yamaguchi, Takefumi AU - Higa, Kazunari AU - Suzuki, Terumasa AU - Aketa, Naohiko AU - Dogru, Murat AU - Satake, Yoshiyuki AU - Shimazaki, Jun T2 - Scientific Reports AB - Annual reduction rate of corneal endothelial cell density (ECD) varies among etiologies, however, the cause of chronic endothelial cell loss is still unknown. We recently reported the elevation of inflammatory cytokines in the aqueous humor (AqH) in eyes with bullous keratopathy and low ECD. To evaluate the association between ECD and aqueous cytokine levels, we collected a total of 157 AqH samples prospectively. The AqH levels of cytokines were measured and multivariate analyses were conducted to find the correlation between ECD, aqueous cytokine levels and clinical factors, such as number of previous intraocular surgeries and protein concentration in AqH. As a result, ECD was negatively correlated with specific cytokine levels, including IL-1α, IL-4, IL-13, MIP-1β, TNF-α and E-selectin (all P < 0.05). The aqueous cytokine levels showed different correlations with these clinical factors; the number of previous intraocular surgeries was associated with all cytokines except MIP-1α. The AqH protein concentration and the status of intraocular lens showed similar patterns of elevation of IL-1α, IL-4, IL-6, IL-8, IL-10, IL-13, IL-17A, MIP-1β, MCP-1, E-selectin, P-selectin and sICAM-1. In conclusion, elevation of AqH cytokine levels was associated with reduced ECDs. AqH cytokine levels showed significant correlations with clinical factors associated with low ECDs. DA - 2017/10/19/ PY - 2017 DO - 10.1038/s41598-017-14131-3 DP - www.nature.com VL - 7 IS - 1 SP - 13603 LA - en SN - 2045-2322 UR - https://www.nature.com/articles/s41598-017-14131-3 Y2 - 2020/09/18/10:46:25 L1 - https://www.nature.com/articles/s41598-017-14131-3.pdf L2 - https://www.nature.com/articles/s41598-017-14131-3#ref-CR3 ER - TY - JOUR TI - Baseline Factors Related to Endothelial Cell Loss Following Penetrating Keratoplasty AU - Lass, Jonathan H. AU - Beck, Roy W. AU - Benetz, Beth Ann AU - Dontchev, Mariya AU - Gal, Robin L. AU - Holland, Edward J. AU - Kollman, Craig AU - Mannis, Mark J. AU - Price, Francis AU - Raber, Irving AU - Stark, Walter AU - Stulting, R. Doyle AU - Sugar, Alan AU - Group, for the Cornea Donor Study Investigator T2 - Archives of Ophthalmology AB -

Objective

To identify baseline (donor, recipient, and operative) factors that affect endothelial cell loss following penetrating keratoplasty for a moderate-risk condition (principally Fuchs dystrophy or pseudophakic or aphakic corneal edema).

Methods

In a subset (n = 567) of Cornea Donor Study participants, preoperative and postoperative endothelial cell densities (ECDs) were determined by a central reading center. Multivariate regression analyses were performed to examine which baseline factors correlated with ECD over time.

Results

Larger grafts (P < .001), younger donor age (P < .001), and female donor (P = .004) were significantly associated with higher ECD during follow-up. Median endothelial cell loss at 5 years was 68% for grafts larger than 8.0 to 9.0 mm in diameter, 75% for grafts 7.0 mm to smaller than 8.0 mm in diameter, and 74% for grafts 8.0 mm in diameter. Grafts from female donors experienced a 67% cell loss compared with a 72% cell loss among grafts from male donors. Method of tissue retrieval, donor cause of death, history of diabetes, and time from death to preservation or to surgery were not significantly associated with changes in ECD over time.

Conclusions

Following penetrating keratoplasty for endothelial dysfunction conditions, larger donor graft size, younger donor age, and female donor were associated with higher ECD over 5 years. These data warrant exploring the possibility that similar associations may exist following endothelial keratoplasty.

Trial Registration

clinicaltrials.gov Identifier: NCT00006411 DA - 2011/09/12/ PY - 2011 DO - 10.1001/archophthalmol.2011.102 DP - jamanetwork.com VL - 129 IS - 9 SP - 1149 EP - 1154 J2 - Arch Ophthalmol LA - en SN - 0003-9950 UR - https://jamanetwork.com/journals/jamaophthalmology/fullarticle/1106439 Y2 - 2020/09/18/10:52:03 L1 - https://jamanetwork.com/journals/jamaophthalmology/articlepdf/1106439/ecs15019_1149_1154.pdf L2 - https://jamanetwork.com/journals/jamaophthalmology/fullarticle/1106439 ER - TY - JOUR TI - Corneal endothelial cell dysfunction: etiologies and management AU - Feizi, Sepehr T2 - Therapeutic Advances in Ophthalmology AB - A transparent cornea is essential for the formation of a clear image on the retina. The human cornea is arranged into well-organized layers, and each layer plays a significant role in maintaining the transparency and viability of the tissue. The endothelium has both barrier and pump functions, which are important for the maintenance of corneal clarity. Many etiologies, including Fuchs’ endothelial corneal dystrophy, surgical trauma, and congenital hereditary endothelial dystrophy, lead to endothelial cell dysfunction. The main treatment for corneal decompensation is replacement of the abnormal corneal layers with normal donor tissue. Nowadays, the trend is to perform selective endothelial keratoplasty, including Descemet stripping automated endothelial keratoplasty and Descemet’s membrane endothelial keratoplasty, to manage corneal endothelial dysfunction. This selective approach has several advantages over penetrating keratoplasty, including rapid recovery of visual acuity, less likelihood of graft rejection, and better patient satisfaction. However, the global limitation in the supply of donor corneas is becoming an increasing challenge, necessitating alternatives to reduce this demand. Consequently, in vitro expansion of human corneal endothelial cells is evolving as a sustainable choice. This method is intended to prepare corneal endothelial cells in vitro that can be transferred to the eye. Herein, we describe the etiologies and manifestations of human corneal endothelial cell dysfunction. We also summarize the available options for as well as recent developments in the management of corneal endothelial dysfunction. DA - 2018/12/07/ PY - 2018 DO - 10.1177/2515841418815802 DP - PubMed Central VL - 10 J2 - Ther Adv Ophthalmol SN - 2515-8414 ST - Corneal endothelial cell dysfunction UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6293368/ Y2 - 2020/09/18/12:54:13 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6293368/pdf/10.1177_2515841418815802.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6293368/ ER - TY - JOUR TI - Intracellular BKCa (iBKCa) channels AU - Singh, Harpreet AU - Stefani, Enrico AU - Toro, Ligia T2 - The Journal of Physiology AB - The large conductance calcium- and voltage-activated potassium channel (BKCa) is widely expressed at the plasma membrane. This channel is involved in a variety of fundamental cellular functions including excitability, smooth muscle contractility, and Ca2+ homeostasis, as well as in pathological situations like proinflammatory responses in rheumatoid arthritis, and cancer cell proliferation. Immunochemical, biochemical and pharmacological studies from over a decade have intermittently shown the presence of BKCa in intracellular organelles. To date, intracellular BKCa (iBKCa) has been localized in the mitochondria, endoplasmic reticulum, nucleus and Golgi apparatus but its functional role remains largely unknown except for the mitochondrial BKCa whose opening is thought to play a role in protecting the heart from ischaemic injury. In the nucleus, pharmacology suggests a role in regulating nuclear Ca2+, membrane potential and eNOS expression. Establishing the molecular correlates of iBKCa, the mechanisms defining iBKCa organelle-specific targeting, and their modulation are challenging questions. This review summarizes iBKCa channels, their possible functions, and efforts to identify their molecular correlates. DA - 2012/// PY - 2012 DO - 10.1113/jphysiol.2011.215533 DP - Wiley Online Library VL - 590 IS - 23 SP - 5937 EP - 5947 LA - en SN - 1469-7793 UR - https://physoc.onlinelibrary.wiley.com/doi/abs/10.1113/jphysiol.2011.215533 Y2 - 2020/09/18/23:30:55 L1 - https://physoc.onlinelibrary.wiley.com/doi/pdfdirect/10.1113/jphysiol.2011.215533 L2 - https://physoc.onlinelibrary.wiley.com/doi/full/10.1113/jphysiol.2011.215533 ER - TY - JOUR TI - BK potassium channel modulation by leucine-rich repeat-containing proteins AU - Yan, Jiusheng AU - Aldrich, Richard W. T2 - Proceedings of the National Academy of Sciences AB - Molecular diversity of ion channel structure and function underlies variability in electrical signaling in nerve, muscle, and nonexcitable cells. Regulation by variable auxiliary subunits is a major mechanism to generate tissue- or cell-specific diversity of ion channel function. Mammalian large-conductance, voltage- and calcium-activated potassium channels (BK, KCa1.1) are ubiquitously expressed with diverse functions in different tissues or cell types, consisting of the pore-forming, voltage- and Ca2+-sensing α-subunits (BKα), either alone or together with the tissue-specific auxiliary β-subunits (β1–β4). We recently identified a leucine-rich repeat (LRR)-containing membrane protein, LRRC26, as a BK channel auxiliary subunit, which causes an unprecedented large negative shift (∼140 mV) in voltage dependence of channel activation. Here we report a group of LRRC26 paralogous proteins, LRRC52, LRRC55, and LRRC38 that potentially function as LRRC26-type auxiliary subunits of BK channels. LRRC52, LRRC55, and LRRC38 produce a marked shift in the BK channel’s voltage dependence of activation in the hyperpolarizing direction by ∼100 mV, 50 mV, and 20 mV, respectively, in the absence of calcium. They along with LRRC26 show distinct expression in different human tissues: LRRC26 and LRRC38 mainly in secretory glands, LRRC52 in testis, and LRRC55 in brain. LRRC26 and its paralogs are structurally and functionally distinct from the β-subunits and we designate them as a γ family of the BK channel auxiliary proteins, which potentially regulate the channel’s gating properties over a spectrum of different tissues or cell types. DA - 2012/05/15/ PY - 2012 DO - 10.1073/pnas.1205435109 DP - www.pnas.org VL - 109 IS - 20 SP - 7917 EP - 7922 J2 - PNAS LA - en SN - 0027-8424, 1091-6490 UR - https://www.pnas.org/content/109/20/7917 Y2 - 2020/10/29/17:29:52 L1 - https://www.pnas.org/content/pnas/109/20/7917.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/22547800 L2 - https://www.pnas.org/content/109/20/7917.short KW - accessory protein KW - cotranslational expression KW - patch clamp KW - signal peptide ER - TY - JOUR TI - Differentiation of Diabetes by Pathophysiology, Natural History, and Prognosis AU - Skyler, Jay S. AU - Bakris, George L. AU - Bonifacio, Ezio AU - Darsow, Tamara AU - Eckel, Robert H. AU - Groop, Leif AU - Groop, Per-Henrik AU - Handelsman, Yehuda AU - Insel, Richard A. AU - Mathieu, Chantal AU - McElvaine, Allison T. AU - Palmer, Jerry P. AU - Pugliese, Alberto AU - Schatz, Desmond A. AU - Sosenko, Jay M. AU - Wilding, John P. H. AU - Ratner, Robert E. T2 - Diabetes AB - The American Diabetes Association, JDRF, the European Association for the Study of Diabetes, and the American Association of Clinical Endocrinologists convened a research symposium, “The Differentiation of Diabetes by Pathophysiology, Natural History and Prognosis” on 10–12 October 2015. International experts in genetics, immunology, metabolism, endocrinology, and systems biology discussed genetic and environmental determinants of type 1 and type 2 diabetes risk and progression, as well as complications. The participants debated how to determine appropriate therapeutic approaches based on disease pathophysiology and stage and defined remaining research gaps hindering a personalized medical approach for diabetes to drive the field to address these gaps. The authors recommend a structure for data stratification to define the phenotypes and genotypes of subtypes of diabetes that will facilitate individualized treatment. DA - 2017/02/01/ PY - 2017 DO - 10.2337/db16-0806 DP - diabetes.diabetesjournals.org VL - 66 IS - 2 SP - 241 EP - 255 LA - en SN - 0012-1797, 1939-327X UR - https://diabetes.diabetesjournals.org/content/66/2/241 Y2 - 2020/12/06/16:44:25 L1 - https://diabetes.diabetesjournals.org/content/diabetes/66/2/241.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/27980006 L2 - https://diabetes.diabetesjournals.org/content/66/2/241 ER - TY - JOUR TI - Role of Insulin in Regulation of Na+-/K+-Dependent ATPase Activity and Pump Function in Corneal Endothelial Cells AU - Hatou, Shin AU - Yamada, Masakazu AU - Akune, Yoko AU - Mochizuki, Hiroshi AU - Shiraishi, Atsushi AU - Joko, Takeshi AU - Nishida, Teruo AU - Tsubota, Kazuo T2 - Investigative Ophthalmology & Visual Science DA - 2010/08/01/ PY - 2010 DO - 10.1167/iovs.09-4027 DP - iovs.arvojournals.org VL - 51 IS - 8 SP - 3935 EP - 3942 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?articleid=2126373 Y2 - 2020/12/06/23:52:28 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/932964/z7g00810003935.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2126373 ER - TY - JOUR TI - Diabetes and beta cell function: from mechanisms to evaluation and clinical implications AU - Cernea, Simona AU - Dobreanu, Minodora T2 - Biochemia Medica AB - Diabetes is a complex, heterogeneous condition that has beta cell dysfunction at its core. Many factors (e.g. hyperglycemia/glucotoxicity, lipotoxicity, autoimmunity, inflammation, adipokines, islet amyloid, incretins and insulin resistance) influence the function of pancreatic beta cells. Chronic hyperglycaemia may result in detrimental effects on insulin synthesis/secretion, cell survival and insulin sensitivity through multiple mechanisms: gradual loss of insulin gene expression and other beta-cell specific genes; chronic endoplasmic reticulum stress and oxidative stress; changes in mitochondrial number, morphology and function; disruption in calcium homeostasis. In the presence of hyperglycaemia, prolonged exposure to increased free fatty acids result in accumulation of toxic metabolites in the cells ("lipotoxicity"), finally causing decreased insulin gene expression and impairment of insulin secretion. The rest of the factors/mechanisms which impact on the course of the disease are also discusses in detail. The correct assessment of beta cell function requires a concomitant quantification of insulin secretion and insulin sensitivity, because the two variables are closely interrelated. In order to better understand the fundamental pathogenetic mechanisms that contribute to disease development in a certain individual with diabetes, additional markers could be used, apart from those that evaluate beta cell function. The aim of the paper was to overview the relevant mechanisms/factors that influence beta cell function and to discuss the available methods of its assessment. In addition, clinical considerations are made regarding the therapeutical options that have potential protective effects on beta cell function/mass by targeting various underlying factors and mechanisms with a role in disease progression. DA - 2013/// PY - 2013 DO - 10.11613/bm.2013.033 DP - PubMed VL - 23 IS - 3 SP - 266 EP - 280 J2 - Biochem Med (Zagreb) LA - eng SN - 1330-0962 ST - Diabetes and beta cell function L1 - https://www.biochemia-medica.com/assets/images/upload/xml_tif/bm-23-266.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/24266296 KW - Animals KW - Autoimmunity KW - Diabetes Mellitus KW - Humans KW - Inflammation KW - Insulin Resistance KW - Insulin-Secreting Cells KW - Lipids KW - Risk Factors ER - TY - JOUR TI - Review of Corneal Endothelial Specular Microscopy for FDA Clinical Trials of Refractive Procedures, Surgical Devices and New Intraocular Drugs and Solutions AU - McCarey, Bernard E. AU - Edelhauser, Henry F. AU - Lynn, Michael J. T2 - Cornea AB - Specular microscopy can provide a non-invasive morphological analysis of the corneal endothelial cell layer from subjects enrolled in clinical trials. The analysis provides a measure of the endothelial cell physiological reserve from aging, ocular surgical procedures, pharmaceutical exposure, and general health of the corneal endothelium. The purpose of this review is to discuss normal and stressed endothelial cell morphology, the techniques for determining the morphology parameters, and clinical trial applications. DA - 2008/01// PY - 2008 DO - 10.1097/ICO.0b013e31815892da DP - PubMed Central VL - 27 IS - 1 SP - 1 EP - 16 J2 - Cornea SN - 0277-3740 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3062434/ Y2 - 2020/12/11/01:30:12 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3062434/pdf/nihms239342.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3062434/ ER - TY - JOUR TI - A review of the evidence for in vivo corneal endothelial regeneration AU - Van den Bogerd, Bert AU - Dhubhghaill, Sorcha Ní AU - Koppen, Carina AU - Tassignon, Marie-José AU - Zakaria, Nadia T2 - Survey of Ophthalmology AB - Human corneal endothelium has long been thought to be a nonmitotic cell layer with no endogenous reparative potential. Pathologies that damage endothelial function result in corneal decompensation and, if untreated, blindness. The mainstay of treatment involves partial or complete corneal replacement, amounting to 40% of all corneal transplants performed worldwide. We summarize the case reports describing complications postoperatively in the form of (sub)total graft detachment and those resulting in postoperative bare stroma. Complications during cataract and glaucoma surgeries leading to an uncovered posterior cornea are also included. We discuss the newer treatment strategies that are alternatives for current Descemet membrane endothelial keratoplasty and Descemet stripping automated endothelial keratoplasty, including partial grafts and stripping of the diseased cell layer. In more than half of the cases reviewed, corneal transparency returned despite incomplete or no corneal endothelial cell transplantation. We question the existing paradigm concerning corneal endothelial wound healing in vivo. The data support further clinical study to determine the safety of simple descemethorexis in central endothelial pathologies, such as Fuchs endothelial corneal dystrophy, where presence of healthy peripheral cells may allow successful corneal recompensation without the need for donor cells. DA - 2018/03/01/ PY - 2018 DO - 10.1016/j.survophthal.2017.07.004 DP - ScienceDirect VL - 63 IS - 2 SP - 149 EP - 165 J2 - Survey of Ophthalmology LA - en SN - 0039-6257 UR - http://www.sciencedirect.com/science/article/pii/S0039625717301054 Y2 - 2020/12/14/16:17:25 L1 - https://pdf.sciencedirectassets.com/271199/1-s2.0-S0039625718X00022/1-s2.0-S0039625717301054/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEEEaCXVzLWVhc3QtMSJHMEUCIQCpNvPKDtQbkxrEU9RbxjKJiH1uSvYJwGd%2FeFcvnzIxCwIgNwgXSUkxJVebMNxSS9FIu5chwtjCzZP0RAokux24ncwqvQMI2f%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARADGgwwNTkwMDM1NDY4NjUiDNYmoN%2Btx2SybmHS8yqRA%2F58T5NUdfyguLQcjYAv1y1VGzLHcuMT648tLwCHGWpcyuOlw7gJWjxf7%2FeKY06lzFuCUusuGxSz16Jkyx2vYTCppAZidAORJ3Az%2BU%2FhpWLcO5d2KJ1wHUGAMdIbdrBgPHte1x%2Bg%2B1nxn9hT6QlISDyuvzo1CD7JtHDu2RP2W3HSOWabq7GbB%2F3Y7%2BDa5V7%2BCA3taHJx5EmM050fR3WYXh2v7zSs00sX9SxWWBJ0V9wqmKfHFf8Yjv93k7x0kzVO9OMo0HvZzwaLc1UVL5z2sIj2NawntSJeMqiVaOvZIDZwHRPxyHGy44FA5ztywemgV8n2PU1BgB7iHuVvu5TM9wcGE6uZQILU4SOT0un7NdDEabi4YIcTYYenygloBhmMegnUfb2%2BzRGeDTgpNNDDeCdyzubSXhCAYR%2B7zBfZY15H873FZyZZkbuGfLNyeg4Vquw4RKuVbT9OCGAr1KFY6H5dmncQrcgFqlfBJXedJ49PnnE2fByXXJQ6JP9sKOfj15aRhs8v0uYsYTGRxunHrebwMNGa3v4FOusBeVmmSkHkaXUOZqKK4CuG0NsLmOQSxlIe%2FkIrrVGyJNDNA%2FXsZg5kyyiH1TBYBhjbxl1O5xTsAfExDS%2BYmmeVsJPWViBTIG4YJTSM%2BAB%2BoXiYKxDr8LRCYG%2FVfU%2FQXE99vYMrKhjKfgqU%2F4cSOyko1o0FI31u7pNvIoX8urlkxiyV7N1uuwfrIzbGE1KpSUNG95Kj17PcbQtWsDYL98Lu8pWRcgsqbQIE5HBlFiJipNRhR8bkoCoeptCYb0%2FHMHlh%2B0bZAYIsULUrvzjBCHkXrstH87Dz273ojFI6r5x0ADDTgOxa0mmG%2FpWYjg%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20201214T161725Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY5PJ6W67B%2F20201214%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=08f6808837114888c170ebca80be754c2369a654e78db7164160f1b48123fb80&hash=ea4e9beaf7a8cf4c545a1e034f20434b7b297d3df8cf5afdaf593a40e2e742fd&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0039625717301054&tid=spdf-8cd67ba0-3b87-41bb-bfea-bdf21b1b9aea&sid=c037752c66f698471c1b39f01eec199d353agxrqa&type=client L2 - https://www.sciencedirect.com/science/article/pii/S0039625717301054#bib27 KW - corneal endothelial regeneration KW - corneal endothelial stripping descemetorhexis KW - corneal endothelium KW - Fuchs dystrophy KW - spontaneous clearance ER - TY - CHAP TI - Diabetes Mellitus: Diagnosis, Classification, and Pathophysiology AU - Powers, Alvin C. AU - Niswender, Kevin D. AU - Evans-Molina, Carmella T2 - Harrison's Principles of Internal Medicine A2 - Jameson, J. Larry A2 - Fauci, Anthony S. A2 - Kasper, Dennis L. A2 - Hauser, Stephen L. A2 - Longo, Dan L. A2 - Loscalzo, Joseph AB - Diabetes mellitus (DM) refers to a group of common metabolic disorders that share the phenotype of hyperglycemia. Several distinct types of DM are caused by a complex interaction of genetics and environmental factors. Depending on the etiology of the DM, factors contributing to hyperglycemia include reduced insulin secretion, decreased glucose utilization, and increased glucose production. The metabolic dysregulation associated with DM causes secondary pathophysiologic changes in multiple organ systems that impose a tremendous burden on the individual with diabetes and on the health care system. In the United States, DM is the leading cause of end-stage renal disease (ESRD), nontraumatic lower extremity amputations, and adult blindness. It also predisposes to cardiovascular diseases. With an increasing incidence worldwide, DM is likely to continue to be a leading cause of morbidity and mortality in the future. CY - New York, NY DA - 2018/// PY - 2018 DP - Access Medicine ET - 20 PB - McGraw-Hill Education ST - Diabetes Mellitus UR - accessmedicine.mhmedical.com/content.aspx?aid=1156520865 Y2 - 2020/12/14/17:13:54 L2 - http://accessmedicine.mhmedical.com/content.aspx?bookid=2129§ionid=192288322#1156520781 N1 - | ER - TY - JOUR TI - Corneal endothelium evaluation in type I and type II diabetes mellitus AU - Roszkowska, A. M. AU - Tringali, C. G. AU - Colosi, P. AU - Squeri, C. A. AU - Ferreri, G. T2 - Ophthalmologica. Journal International D'ophtalmologie. International Journal of Ophthalmology. Zeitschrift Fur Augenheilkunde AB - BACKGROUND: The purpose of this study is to evaluate the corneal endothelium in type I and type II diabetic patients. METHODS: Seventy-five diabetics divided into type I and type II groups and 62 healthy volunteers took part in the study. The mean endothelial cell density and morphology, and the central corneal thickness were evaluated and statistical analysis was done. RESULTS: All evaluated parameters were found to be significantly different in both diabetic groups with reduction of the mean cell density of 5% in type II and of 11% in type I diabetes with respect to the normal age-matched control group. Important alterations of endothelial morphology were observed. The central corneal pachymetry was significantly higher in diabetics, with p < 0.01 in the type I group and p < 0.05 in the type II group. CONCLUSION: It is concluded that corneal endothelium in diabetics should still be considered as a tissue under continuous metabolic stress with consequent high vulnerability, especially in case of any external insult such as a surgical procedure. DA - 1999/// PY - 1999 DO - 10.1159/000027431 DP - PubMed VL - 213 IS - 4 SP - 258 EP - 261 J2 - Ophthalmologica LA - eng SN - 0030-3755 L2 - http://www.ncbi.nlm.nih.gov/pubmed/10420110 KW - Adult KW - Cell Count KW - Corneal Diseases KW - Diabetes Mellitus, Type 1 KW - Diabetes Mellitus, Type 2 KW - Endothelium, Corneal KW - Female KW - Humans KW - Male KW - Middle Aged KW - Reproducibility of Results ER - TY - JOUR TI - The effects of diabetes mellitus on the corneal endothelium: A review AU - Goldstein, Andrew S. AU - Janson, Ben J. AU - Skeie, Jessica M. AU - Ling, Jennifer J. AU - Greiner, Mark A. T2 - Survey of Ophthalmology AB - The corneal endothelium plays a critical role in maintaining corneal clarity. There is an expected decline in cell density with age and disease, and maintaining the health of this cell layer is important as corneal endothelial cells generally are amitotic in vivo. Diabetes mellitus is a highly prevalent disease that damages the corneal endothelium. Diabetes causes structural and functional impairments in the corneal endothelium that decrease cellular reserve in response to stress. These effects have implications to consider for diabetic patients undergoing anterior segment surgery, and for corneal surgeons who use diabetic donor tissue and treat diabetic patients. In this review, we discuss the specifics of how diabetes mellitus impacts the corneal endothelium including alterations in cell morphology, cell density, ultrastructure, pump and barrier function, cataract surgery outcomes, and corneal transplant outcomes with attention to the use of diabetic donor tissue and diabetic transplant recipients. DA - 2020/08//Jul - undefined PY - 2020 DO - 10.1016/j.survophthal.2019.12.009 DP - PubMed VL - 65 IS - 4 SP - 438 EP - 450 J2 - Surv Ophthalmol LA - eng SN - 1879-3304 ST - The effects of diabetes mellitus on the corneal endothelium L2 - http://www.ncbi.nlm.nih.gov/pubmed/31926185 KW - corneal edema KW - corneal endothelium KW - corneal transplantation KW - diabetes complications KW - diabetes mellitus ER - TY - ELEC TI - The Causal Role of Mitochondrial Dynamics in Regulating Insulin Resistance in Diabetes: Link through Mitochondrial Reactive Oxygen Species AU - Lin, Hung-Yu AU - Weng, Shao-Wen AU - Chang, Yen-Hsiang AU - Su, Yu-Jih AU - Chang, Chih-Min AU - Tsai, Chia-Jen AU - Shen, Feng-Chih AU - Chuang, Jiin-Haur AU - Lin, Tsu-Kung AU - Liou, Chia-Wei AU - Lin, Ching-Yi AU - Wang, Pei-Wen T2 - Oxidative Medicine and Cellular Longevity AB - Background. Mitochondrial dynamics (mtDYN) has been proposed as a bridge between mitochondrial dysfunction and insulin resistance (IR), which is involved in the pathogenesis of type 2 diabetes (T2D). Our previous study has identified that mitochondrial DNA (mtDNA) haplogroup B4 is a T2D-susceptible genotype. Using transmitochondrial cybrid model, we have confirmed that haplogroup B4 contributes to cellular IR as well as a profission mtDYN, which can be reversed by antioxidant treatment. However, the causal relationship between mtDYN and cellular IR pertaining to T2D-susceptible haplogroup B4 remains unanswered. Methods. To dissect the mechanisms between mtDYN and IR, knockdown or overexpression of MFN1, MFN2, DRP1, and FIS1 was performed using cybrid B4. We then examined the mitochondrial network and mitochondrial oxidative stress (mtROS) as well as insulin signaling IRS-AKT pathway and glucose transporters (GLUT) translocation to plasma membrane stimulated by insulin. We employed Drp1 inhibitor, mdivi-1, to interfere with endogenous expression of fission to validate the pharmacological effects on IR. Results. Overexpression of MFN1 or MFN2 increased mitochondrial network and reduced mtROS, while knockdown had an opposing effect. In contrast, overexpression of DRP1 or FIS1 decreased mitochondrial network and increased mtROS, while knockdown had an opposing effect. Concomitant with the enhanced mitochondrial network, activation of the IRS1-AKT pathway and GLUT translocation stimulated by insulin were improved. On the contrary, suppression of mitochondrial network caused a reduction of the IRS1-AKT pathway and GLUT translocation stimulated by insulin. Pharmacologically inhibiting mitochondrial fission by the Drp1 inhibitor, mdivi-1, also rescued mitochondrial network, reduced mtROS, and improved insulin signaling of diabetes-susceptible cybrid cells. Conclusion. Our results discovered the causal role of mtDYN proteins in regulating IR resulted from diabetes-susceptible mitochondrial haplogroup. The existence of a bidirectional interaction between mtDYN and mtROS plays an important role. Direct intervention to reverse profission in mtDYN provides a novel therapeutic strategy for IR and T2D. DA - 2018/09/30/ PY - 2018 LA - en M3 - Research Article ST - The Causal Role of Mitochondrial Dynamics in Regulating Insulin Resistance in Diabetes UR - https://www.hindawi.com/journals/omcl/2018/7514383/ Y2 - 2020/12/16/00:07:04 L1 - http://downloads.hindawi.com/journals/omcl/2018/7514383.pdf L2 - https://www.hindawi.com/journals/omcl/2018/7514383/ ER - TY - ELEC TI - Ottawa Hospital Research Institute UR - http://www.ohri.ca/programs/clinical_epidemiology/oxford.asp Y2 - 2021/01/28/13:37:00 L2 - http://www.ohri.ca/programs/clinical_epidemiology/oxford.asp ER - TY - JOUR TI - Pharmacologic Approaches to Glycemic Treatment: Standards of Medical Care in Diabetes—2020 AU - American Diabetes Association T2 - Diabetes Care AB - The American Diabetes Association (ADA) “Standards of Medical Care in Diabetes” includes the ADA’s current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee (https://doi.org/10.2337/dc20-SPPC), are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA’s clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc20-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC. DA - 2020/01/01/ PY - 2020 DO - 10.2337/dc20-S009 DP - care.diabetesjournals.org VL - 43 IS - Supplement 1 SP - S98 EP - S110 LA - en SN - 0149-5992, 1935-5548 ST - 9. Pharmacologic Approaches to Glycemic Treatment UR - https://care.diabetesjournals.org/content/43/Supplement_1/S98 Y2 - 2021/02/10/18:34:20 L1 - https://care.diabetesjournals.org/content/diacare/43/Supplement_1/S98.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/31862752 L2 - https://care.diabetesjournals.org/content/43/Supplement_1/S98 ER - TY - JOUR TI - Identification of Circulating Fibrocytes and Dendritic Derivatives in Corneal Endothelium of Patients With Fuchs' Dystrophy AU - Roo, An-Katrien De AU - Wouters, Jasper AU - Govaere, Olivier AU - Foets, Beatrijs AU - Oord, Joost J. van den T2 - Investigative Ophthalmology & Visual Science DA - 2017/01/01/ PY - 2017 DO - 10.1167/iovs.16-20880 DP - iovs.arvojournals.org VL - 58 IS - 1 SP - 670 EP - 681 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?articleid=2600835 Y2 - 2021/02/12/16:01:13 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/935965/i1552-5783-58-1-670.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2600835 ER - TY - JOUR TI - Corneal Endothelial Morphology in Children with Type 1 Diabetes AU - Anbar, Mohamed AU - Ammar, Hatem AU - Mahmoud, Ramadan A. T2 - Journal of Diabetes Research AB - Aim. To investigate corneal endothelial cell morphological in children with type 1 diabetes and to determine the systemic and local factors that contribute to these changes. Methods. One hundred sixty eyes of 80 children with type 1 diabetes and 80 eyes of 40 normal children as a control during the period from July 2015 to February 2016 underwent full clinical and ophthalmologic examination. We measured the central corneal thickness (CCT), endothelial cell density (ECD), ploymegathism, and pleomorphism using a noncontact specular microscope. Results. The mean age of the diabetic children was 8.22 ± 3.11 years. The mean duration of type 1 diabetes was 3.51 ± 2.23 years. The mean CCT was significantly higher: 537 ± 33.41 microns (right eye), in the diabetic group compared to the control group. The mean ECD in patients with type 1 diabetes was 3149.84 ± 343.75 cells/mm2 (right eye), and it was significantly lower than in the control group. Furthermore, pleomorphism was significantly lower 48.73 ± 5.43% (right eye), in the diabetic group compared to the control group. The mean polymegathism was significantly higher 37.96 ± 5.61% (right eye), in the diabetic group compared to the control group. All of these changes are significantly correlated only with the duration of diabetes. Conclusions. Diabetic children have thicker corneas, lower ECD, an increased polymegathism, and a decreased pleomorphism. The duration of diabetes is the factor that affects all of these changes. To what extent these changes affect visional function on long term needs to be investigated in further studies. DA - 2016/// PY - 2016 DO - 10.1155/2016/7319047 DP - PubMed Central VL - 2016 J2 - J Diabetes Res SN - 2314-6745 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939174/ Y2 - 2021/02/17/19:59:19 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939174/pdf/JDR2016-7319047.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939174/ ER - TY - JOUR TI - Quantitative corneal anatomy: evaluation of the effect of diabetes duration on the endothelial cell density and corneal thickness AU - Calvo‐Maroto, Ana M. AU - Cerviño, Alejandro AU - Perez‐Cambrodí, Rafael J. AU - García‐Lázaro, Santiago AU - Sanchis‐Gimeno, Juan A. T2 - Ophthalmic and Physiological Optics AB - Purpose To evaluate the differences in endothelial cell density (ECD) and central corneal thickness (CCT) between type II diabetic patients and age-matched healthy controls, and determine the impact of time from diagnosis. Methods This is a comparative study of 77 eyes of type II diabetic patients (33 males, 44 females) and 80 eyes of healthy subjects (42 males, and 38 females) whose ages ranged from 38 to 56 years. CCT, ECD, HbA1c levels, and Goldmann tonometry were measured. Results The CCT was significantly higher and the ECD significantly lower in long-term diabetic patients (10 years + since diagnosis) when compared with short-term diabetic patients (<1 year since diagnosis) and controls (both p < 0.001). No significant differences in CCT (p = 0.30) and ECD (p = 0.31) were found between control groups. Multivariate analysis of variance indicated that there was a significant effect of the diabetes duration in CCT and ECD. In diabetic patients, a two-way analysis of variance showed that CCT was significantly different for a 7.5% HbA1c cut-off value, and ECD for both 7.0% and 7.5% HbA1c cut-off values. Conclusion Type II diabetes causes a significant alteration in corneal structure and function in the long term. Our study seems to confirm the effect of diabetes duration and poor glycaemic control on CCT and ECD changes. DA - 2015/// PY - 2015 DO - https://doi.org/10.1111/opo.12191 DP - Wiley Online Library VL - 35 IS - 3 SP - 293 EP - 298 LA - en SN - 1475-1313 ST - Quantitative corneal anatomy UR - https://onlinelibrary.wiley.com/doi/abs/10.1111/opo.12191 Y2 - 2021/02/17/21:06:50 L2 - https://onlinelibrary.wiley.com/doi/abs/10.1111/opo.12191 KW - corneal thickness KW - diabetes mellitus type II KW - duration of diabetes KW - endothelial cell density KW - quantitative anatomy ER - TY - JOUR TI - Cumulative Effects of Smoking and Diabetes Mellitus on Corneal Endothelial Cell Parameters AU - Cankurtaran, Veysel AU - Tekin, Kemal T2 - Cornea AB - PURPOSE: To compare the corneal endothelial morphometric properties and central corneal thickness (CCT) values in patients with diabetes mellitus (DM) and age-matched healthy subjects and to determine whether smoking increases the effects of DM on these corneal parameters. METHODS: This prospective study included patients with type 2 DM and their age-matched controls. The smoking history of all participants was evaluated. Corneal endothelial cell properties including endothelial cell density (ECD), average cell area (AVG), coefficient of variation of cell area (CV), and percentage of hexagonal cells (HEX) were obtained using a noncontact specular microscope. Consequently, CCT was measured using an ultrasound pachymeter. RESULTS: This research analyzed 153 subjects in the DM group and 146 subjects in the control group. There were no statistically significant differences in the age, sex, and smoking status of the participants in 2 groups (P > 0.05). The corneal endothelial cell measurements including ECD, AVG, CV, and HEX did not show any statistically significant differences between these groups (P > 0.05). However, CCT of patients with DM was statistically significantly thicker than that of the controls (P = 0.005). The ECD values of the smokers with DM (2435 ± 325 cells/mm) were statistically significantly lower than those of nonsmoker healthy subjects (2559 ± 279 cells/mm P = 0.008). However, the AVG, CV, HEX, and CCT values of the smokers with DM were not statistically significantly different compared with nonsmoker healthy subjects (P > 0.05). CONCLUSIONS: Although neither only DM nor only smoking has a statistically significant effect on corneal endothelial morphometric properties, coexistence of DM and smoking causes a significant decrease in ECD. DA - 2019/01// PY - 2019 DO - 10.1097/ICO.0000000000001718 DP - PubMed VL - 38 IS - 1 SP - 78 EP - 83 J2 - Cornea LA - eng SN - 1536-4798 L2 - http://www.ncbi.nlm.nih.gov/pubmed/30124593 KW - Adult KW - Aged KW - Cell Count KW - Corneal Diseases KW - Corneal Pachymetry KW - Diabetes Mellitus, Type 2 KW - Endothelium, Corneal KW - Female KW - Follow-Up Studies KW - Humans KW - Male KW - Middle Aged KW - Prospective Studies KW - Smoking ER - TY - ELEC TI - Changes in Choroidal Thickness and Corneal Parameters in Diabetic Eyes - Saulius Galgauskas, Guoda Laurinavičiūtė, Dovilė Norvydaitė, Simona Stech, Rimvydas Ašoklis, 2016 UR - https://journals.sagepub.com/doi/abs/10.5301/ejo.5000677 Y2 - 2021/02/17/21:47:35 L2 - https://journals.sagepub.com/doi/abs/10.5301/ejo.5000677 ER - TY - JOUR TI - Genetic Determinants of 21-Hydroxylase Autoantibodies Amongst Patients of the Type 1 Diabetes Genetics Consortium AU - Baker, Peter AU - Fain, Pam AU - Kahles, Heinrich AU - Yu, Liping AU - Hutton, John AU - Wenzlau, Janet AU - Rewers, Marian AU - Badenhoop, Klaus AU - Eisenbarth, George T2 - The Journal of Clinical Endocrinology & Metabolism AB - Autoantibodies to 21-hydroxylase (21OH-AA) precede the onset of autoimmune Addison's disease (AD) and are found in 1.5% of individuals with type 1 diabetes mellitus (T1DM). The greatest genetic risk for both disorders is found in the major histocompatibility complex (MHC), suggesting a common pathophysiology between AD and T1DM. Screening for 21OH-AA in newly diagnosed T1DM patients is a valuable prognostic tool, made stronger when MHC genotype is considered.The Type 1 Diabetes Genetics Consortium has collected genotype data in T1DM subjects with tissue-specific autoantibody typing. Genotype and phenotype data in individuals positive and negative for 21OH-AA are compared.Major genetic risk for 21OH-AA is in the MHC haplotypes DRB1*04-DQB1*0302 (primarily DRB1*0404) and DRB1*0301-DQB1*0201. Protective effects in class II MHC haplotypes DRB1*0101-DQB1*0501 and DRB1*0701-DQB1*0202 also were detected. There is no difference in the presence of HLA-B15 and little difference in the presence of HLA-B8 (after class II effects are accounted for) in T1DM patients with 21OH-AA compared with known associations (HLA-B8 positive and HLA-B15 negative) in AD.In 21OH-AA+ subjects, genetic risk is found mainly in MHC class II haplotypes DR3 and DR4 but not class I alleles (HLA-B8 or HLA-B15). This suggests a difference between autoantibody formation (class II dependent) and progression to overt disease (class I dependent) in AD. DA - 2012/08/01/ PY - 2012 DO - 10.1210/jc.2011-2824 DP - Silverchair VL - 97 IS - 8 SP - E1573 EP - E1578 J2 - The Journal of Clinical Endocrinology & Metabolism SN - 0021-972X UR - https://doi.org/10.1210/jc.2011-2824 Y2 - 2021/02/19/15:37:51 L1 - https://academic.oup.com/jcem/article-pdf/97/8/E1573/9040888/jcem1573.pdf L2 - https://academic.oup.com/jcem/article/97/8/E1573/2823165 ER - TY - JOUR TI - Immunogenetics of Type 1 Diabetes Mellitus AU - Morran, Michael P. AU - Vonberg, Andrew AU - Khadra, Anmar AU - Pietropaolo, Massimo T2 - Molecular aspects of medicine AB - Type 1 diabetes mellitus (T1DM) is an autoimmune disease arising through a complex interaction of both genetic and immunologic factors. Similar to the majority of autoimmune diseases, T1DM usually has a relapsing remitting disease course with autoantibody and T cellular responses to islet autoantigens, which precede the clinical onset of the disease process. The immunological diagnosis of autoimmune diseases relies primarily on the detection of autoantibodies in the serum of T1DM patients. Although their pathogenic significance remains uncertain, they have the practical advantage of serving as surrogate biomarkers for predicting the clinical onset of T1DM. Type 1 diabetes is a polygenic disease with a small number of genes having large effects, (i.e. HLA) and a large number of genes having small effects. Risk of T1DM progression is conferred by specific HLA DR/DQ alleles [e.g., DRB1*03-DQB1*0201 (DR3) or DRB1*04-DQB1*0302 (DR4)]. In addition, HLA alleles such as DQB1*0602 are associated with dominant protection from T1DM in multiple populations., A discordance rate of greater than 50% between monozygotic twins indicates a potential involvement of environmental factors on disease development. Viral infections may play a role in the chain of events leading to disease, albeit conclusive evidence linking infections with T1DM remains to be firmly established. Two syndromes have been described in which an immune-mediated form of diabetes occurs as the result of a single gene defect. These syndromes are termed autoimmune polyglandular syndrome type I (APS-I) or autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), and X-linked poyendocrinopathy, immune dysfunction and diarrhea (XPID). These two syndromes are unique models to understand the mechanisms involved in the loss of tolerance to self-antigens in autoimmune diabetes and its associated organ-specific autoimmune disorders. A growing number of animal models of these diseases have greatly helped elucidate the immunologic mechanisms leading to autoimmune diabetes. DA - 2015/04// PY - 2015 DO - 10.1016/j.mam.2014.12.004 DP - PubMed Central VL - 42 SP - 42 EP - 60 J2 - Mol Aspects Med SN - 0098-2997 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4548800/ Y2 - 2021/02/19/18:08:27 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4548800/pdf/nihms654278.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4548800/ ER - TY - JOUR TI - Regulation of HLA class II antigen expression on cultured corneal epithelium by interferon-gamma AU - Iwata, M. AU - Kiritoshi, A. AU - Roat, M. I. AU - Yagihashi, A. AU - Thoft, R. A. T2 - Investigative Ophthalmology & Visual Science AB - The effect of recombinant human interferon gamma (IFN-gamma) on the induction of HLA class II (HLA-DR, -DP, -DQ) antigen expression on human corneal epithelial (HCE) cells was examined in different stages of culture. Primary cultures were established with limbal explants without endothelium. HCE cells in Stage 1 and Stage 2, with cells negative and positive for the 64K corneal keratin (the marker for advanced corneal epithelial differentiation), respectively, were prepared. HCE cells in both stages were treated with IFN-gamma at a concentration of 0 to 1000 U/ml for two to six days and were stained by the avidin-biotin peroxidase complex method. Class II antigens were not detected on HCE cells in either stage without IFN-gamma treatment. IFN-gamma induced three class II antigens on HCE cells in both stages in a dose- and time-dependent manner but at different levels for each antigen (DR greater than DP greater than DQ). In addition, DQ expression was related to cell differentiation, with DQ extremely rare at Stage 1 and more frequent at Stage 2 (5% vs. 20%). These findings indicate that the induction of class II antigens on HCE cells may be regulated by IFN-gamma independently for each of the antigens and that DQ induction may depend upon the differentiation of HCE cells in culture. DA - 1992/08// PY - 1992 DP - PubMed VL - 33 IS - 9 SP - 2714 EP - 2721 J2 - Invest Ophthalmol Vis Sci LA - eng SN - 0146-0404 L2 - http://www.ncbi.nlm.nih.gov/pubmed/1639617 KW - Cell Differentiation KW - Cell Division KW - Cells, Cultured KW - Cornea KW - Epithelial Cells KW - Epithelium KW - HLA-D Antigens KW - HLA-DP Antigens KW - HLA-DQ Antigens KW - HLA-DR Antigens KW - Humans KW - Immunoenzyme Techniques KW - Interferon-gamma KW - Recombinant Proteins ER - TY - JOUR TI - Induction of class II (Ia) alloantigen expression on corneal endothelium in vivo and in vitro. AU - Donnelly, J. J. AU - Li, W. Y. AU - Rockey, J. H. AU - Prendergast, R. A. T2 - Investigative Ophthalmology & Visual Science DA - 1985/04/01/ PY - 1985 DP - iovs.arvojournals.org VL - 26 IS - 4 SP - 575 EP - 580 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?articleid=2177064 Y2 - 2021/02/19/21:13:20 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/933353/575.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2177064 ER - TY - JOUR TI - Immunology of corneal allograft rejection: HLA-DR antigens on human corneal cells. AU - Young, E. AU - Stark, W. J. AU - Prendergast, R. A. T2 - Investigative Ophthalmology & Visual Science DA - 1985/04/01/ PY - 1985 DP - iovs.arvojournals.org VL - 26 IS - 4 SP - 571 EP - 574 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 ST - Immunology of corneal allograft rejection UR - http://iovs.arvojournals.org/article.aspx?articleid=2177105 Y2 - 2021/02/19/21:19:07 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/933353/571.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2177105 ER - TY - JOUR TI - The Molecular Basis of Fuchs’ Endothelial Corneal Dystrophy AU - Zhang, Jie AU - McGhee, Charles N. J. AU - Patel, Dipika V. T2 - Molecular Diagnosis & Therapy AB - Fuchs’ endothelial corneal dystrophy (FECD) is a common disease resulting from corneal endothelial cell dysfunction. It is inherited in an autosomal dominant fashion with incomplete penetrance, and with a female bias. Approximately half of cases occur sporadically, and the remainder are familial. Early and late-onset forms of the disease exist. A review of the literature has revealed more than 15 genes harbouring mutations and/or single nucleotide polymorphisms associated with FECD. The proteins encoded by these genes cover a wide range of endothelial function, including transcription regulation, DNA repair, mitochondrial DNA mutations, targeting of proteins to the cell membrane, deglutamylation of proteins, extracellular matrix secretion, formation of cell–cell and cell–extracellular matrix junctions, water pump, and apoptosis. These genetic variations will form the platform for the further understanding of the pathological basis of the disease, and the development of targeted treatments. This review aims to summarise known genetic variations associated with FECD, discuss any known molecular effects of the variations, how these provide opportunities for targeted therapies, and what therapies are currently in development. DA - 2019/02/01/ PY - 2019 DO - 10.1007/s40291-018-0379-z DP - Springer Link VL - 23 IS - 1 SP - 97 EP - 112 J2 - Mol Diagn Ther LA - en SN - 1179-2000 UR - https://doi.org/10.1007/s40291-018-0379-z Y2 - 2021/02/19/21:22:54 ER - TY - JOUR TI - The expression of HLA antigens by cells in the human cornea AU - Treseler, P. A. AU - Foulks, G. N. AU - Sanfilippo, F. T2 - American Journal of Ophthalmology AB - Although antigens of the human major histocompatibility complex, HLA, appear to be involved in the rejection of corneal allografts, the expression of these antigens by cells of the human cornea remains controversial. Using sensitive immunoperoxidase techniques, we readily demonstrated class I HLA antigens on corneal epithelial, stromal, and endothelial cells, regardless of donor age. Moreover, the expression of class I antigens by epithelium increased markedly from the central to the peripheral cornea. Finally, class II HLA antigens were found on cells scattered throughout both central and peripheral epithelium as well as the stroma. A cornea obtained from a donor of known HLA type expressed all expected and no unexpected polymorphic HLA determinants in the cornea, in a pattern similar to that seen for monomorphic HLA determinants. DA - 1984/12/15/ PY - 1984 DO - 10.1016/0002-9394(84)90696-2 DP - PubMed VL - 98 IS - 6 SP - 763 EP - 772 J2 - Am J Ophthalmol LA - eng SN - 0002-9394 L2 - http://www.ncbi.nlm.nih.gov/pubmed/6594932 KW - Adult KW - Antibodies, Monoclonal KW - Cornea KW - Epithelium KW - Female KW - Histocompatibility Antigens Class II KW - HLA Antigens KW - HLA-DR Antigens KW - Humans KW - Infant KW - Infant, Newborn KW - Male KW - Middle Aged ER - TY - CHAP TI - Chapter 46 - Glutamic Acid Decarboxylase Antibody AU - Crotti, Chiara AU - Selmi, Carlo T2 - Autoantibodies (Third Edition) A2 - Shoenfeld, Yehuda A2 - Meroni, Pier Luigi A2 - Gershwin, M. Eric AB - Glutamic acid decarboxylase (GAD) catalyzes the conversion of glutamic acid into gamma-amino butyric acid within pancreatic islet β cells. Autoantibodies against GAD (GADA) are found in patients with type 1 diabetes mellitus (T1DM), stiff-person syndrome, and epilepsy. Both GAD forms are recognized by GADA, but GAD65 is the predominant autoantigen being recognized in 65% of patients. Up to 90% of children and adolescents who will develop T1DM and patients with latent autoimmune diabetes in adults (LADA) recognize either form. Unlike other islet autoantibodies, GADA persist for many years after the diagnosis in a significant proportion of patients with T1DM and can thus characterize long-standing diabetes. Indeed, it has been demonstrated that the presence of multiple autoantibodies is associated with a high risk of developing diabetes. The identification of GAD as a major autoantigen in T1DM is the basis for new therapy approaches to inhibit the progression of disease by inducing tolerance in GAD-reactive T cells. CY - San Diego DA - 2014/01/01/ PY - 2014 DP - ScienceDirect SP - 385 EP - 389 LA - en PB - Elsevier SN - 978-0-444-56378-1 UR - https://www.sciencedirect.com/science/article/pii/B9780444563781000460 Y2 - 2021/02/19/22:57:55 L2 - https://www.sciencedirect.com/science/article/pii/B9780444563781000460 KW - GAD65 KW - GAD67 KW - gamma-amino butyric acid KW - insulin KW - islet cell autoimmunity KW - isoforms KW - pancreatic islets KW - type 1 diabetes mellitus ER - TY - JOUR TI - Role of Human Corneal Endothelial Cells in T-Cell–Mediated Alloimmune Attack In Vitro AU - Lahdou, Imad AU - Engler, Christoph AU - Mehrle, Stefan AU - Daniel, Volker AU - Sadeghi, Mahmoud AU - Opelz, Gerhard AU - Terness, Peter T2 - Investigative Ophthalmology & Visual Science DA - 2014/03/01/ PY - 2014 DO - 10.1167/iovs.13-11930 DP - iovs.arvojournals.org VL - 55 IS - 3 SP - 1213 EP - 1221 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?articleid=2189465 Y2 - 2021/02/20/01:15:36 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/933471/i1552-5783-55-3-1213.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2189465 ER - TY - JOUR TI - The inhibition of sodium, potassium-stimulated ATPase and corneal swelling: the role played by polyols. AU - Whikehart T2 - Journal of the American Optometric Association AB - Europe PMC is an archive of life sciences journal literature., The inhibition of sodium, potassium-stimulated ATPase and corneal swelling: the role played by polyols. DA - 1995/06/01/ PY - 1995 DP - europepmc.org VL - 66 IS - 6 SP - 331 EP - 333 J2 - J Am Optom Assoc LA - English SN - 0003-0244 ST - The inhibition of sodium, potassium-stimulated ATPase and corneal swelling UR - https://europepmc.org/article/med/7673590 Y2 - 2021/02/20/02:01:22 L2 - http://www.ncbi.nlm.nih.gov/pubmed/7673590 L2 - https://europepmc.org/article/med/7673590 ER - TY - JOUR TI - Clinical observations on the corneal thickness and the corneal endothelium in diabetes mellitus. AU - Busted, N AU - Olsen, T AU - Schmitz, O T2 - The British Journal of Ophthalmology AB - The corneal thickness was measured by pachometry and the corneal endothelium was photographed by specular microscopy in 81 insulin-dependent juvenile diabetic outpatients. The corneal thickness of a normal group, diabetics without and with proliferative retinopathy was (mean +/- SD): 0.527 +/- 0.028, 0.544 +/- 0.028, and 0.566 +/- 0.027 mm, respectively (2p less than 0.01). As revealed in the specular photomicrographs, minute folds in the endothelial layer were found in 13 of the diabetics versus 1 of the normal group (2p less than 0.01). The cell density and the occurrence of dystrophic changes in the endothelium did not differ from those in normal persons. The augmented corneal thickness in the diabetic subjects is tentatively interpreted as minimal corneal swelling. It seemed to be present very early in the disease and may thus be one of the earliest clinically detectable changes off the diabetic eye. DA - 1981/10// PY - 1981 DP - PubMed Central VL - 65 IS - 10 SP - 687 EP - 690 J2 - Br J Ophthalmol SN - 0007-1161 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1039638/ Y2 - 2021/02/20/02:10:18 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1039638/pdf/brjopthal00190-0039.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1039638/ ER - TY - JOUR TI - The effect of diabetes on corneal endothelium: a meta-analysis AU - Zhang, Kaikai AU - Zhao, Liangliang AU - Zhu, Chao AU - Nan, Weijin AU - Ding, Xinfen AU - Dong, Yuchen AU - Zhao, Meisheng T2 - BMC Ophthalmology AB - This research was conducted with the aim to determine the effect of diabetes mellitus on corneal endothelial cells. DA - 2021/02/10/ PY - 2021 DO - 10.1186/s12886-020-01785-3 DP - BioMed Central VL - 21 IS - 1 SP - 78 J2 - BMC Ophthalmology SN - 1471-2415 ST - The effect of diabetes on corneal endothelium UR - https://doi.org/10.1186/s12886-020-01785-3 Y2 - 2021/02/20/02:31:55 L1 - https://bmcophthalmol.biomedcentral.com/track/pdf/10.1186/s12886-020-01785-3 L2 - https://bmcophthalmol.biomedcentral.com/articles/10.1186/s12886-020-01785-3 KW - Corneal endothelium KW - Diabetes mellitus KW - Meta-analysis ER - TY - ELEC TI - Differences in corneal thickness and corneal endothelium related to duration in Diabetes | Eye UR - https://www.nature.com/articles/6701868 Y2 - 2021/02/27/23:25:31 L2 - https://www.nature.com/articles/6701868 ER - TY - JOUR TI - Differences in corneal thickness and corneal endothelium related to duration in diabetes AU - Lee, J. S. AU - Oum, B. S. AU - Choi, H. Y. AU - Lee, J. E. AU - Cho, B. M. T2 - Eye (London, England) AB - PURPOSE: This study evaluated the differences of corneal thickness and corneal endothelial morphology in diabetes compared with age-matched, healthy control subjects; in addition, we tested for correlation according to the duration of diabetes. METHODS: Ultrasound pachymetry and noncontact specular microscopy were performed on 200 patients with diabetes and 100 control subjects. We compared the values for diabetics and normal persons with ANACOVA to adjust for age. Moreover, we examined the correlation between the subject parameters and the duration of diabetes by using a partial correlation coefficient that controlled for age. RESULTS: The diabetic subjects had thicker corneas, less cell density and hexagonality, and more irregular cell size of the corneal endothelium than did the controls (P < 0.05). Central corneal thickness and the coefficient of variation for cell size were significantly higher for diabetes of over 10 years' duration than for diabetes of under 10 years' duration (P < 0.05). The endothelial cell density and percentage of hexagonal cells were lower for diabetes of over 10 years' duration than for diabetes of under 10 years' (P > 0.05). Central corneal thickness was correlated with duration of diabetes (P < 0.05), but corneal endothelial morphology was not (P < 0.05). CONCLUSIONS: Those patients with diabetic duration of over 10 years have more corneal morphological abnormalities, especially the coefficient of variation in cell size, compared with the normal subjects. The central corneal thickness was significantly correlated with diabetic duration after controlling for age. DA - 2006/03// PY - 2006 DO - 10.1038/sj.eye.6701868 DP - PubMed VL - 20 IS - 3 SP - 315 EP - 318 J2 - Eye (Lond) LA - eng SN - 0950-222X L1 - https://www.nature.com/articles/6701868.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/15832184 KW - Adult KW - Age Distribution KW - Age Factors KW - Aged KW - Aged, 80 and over KW - Case-Control Studies KW - Cell Size KW - Cornea KW - Corneal Topography KW - Diabetes Mellitus, Type 1 KW - Endothelium, Corneal KW - Female KW - Humans KW - Male KW - Middle Aged KW - Time Factors ER - TY - JOUR TI - Diabetes mellitus is associated with dry eye syndrome: a meta-analysis. AU - Tk, Yoo AU - E, Oh T2 - International Ophthalmology AB - Europe PMC is an archive of life sciences journal literature., Diabetes mellitus is associated with dry eye syndrome: a meta-analysis. DA - 2019/05/07/ PY - 2019 DO - 10.1007/s10792-019-01110-y DP - europepmc.org VL - 39 IS - 11 SP - 2611 EP - 2620 J2 - Int Ophthalmol LA - English SN - 0165-5701, 1573-2630 ST - Diabetes mellitus is associated with dry eye syndrome UR - https://europepmc.org/article/med/31065905 Y2 - 2021/03/01/19:32:48 L2 - http://www.ncbi.nlm.nih.gov/pubmed/31065905 L2 - https://europepmc.org/article/med/31065905 ER - TY - JOUR TI - Tear Levels of Insulin-Like Growth Factor Binding Protein 3 Correlate With Subbasal Nerve Plexus Changes in Patients With Type 2 Diabetes Mellitus AU - Stuard, Whitney L. AU - Titone, Rossella AU - Robertson, Danielle M. T2 - Investigative Ophthalmology & Visual Science DA - 2017/12/01/ PY - 2017 DO - 10.1167/iovs.17-22425 DP - iovs.arvojournals.org VL - 58 IS - 14 SP - 6105 EP - 6112 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?articleid=2665837 Y2 - 2021/03/01/19:40:54 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/936622/i1552-5783-58-14-6105.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2665837 ER - TY - JOUR TI - Elevated IGFBP3 levels in diabetic tears: a negative regulator of IGF-1 signaling in the corneal epithelium AU - Wu, Yu-Chieh AU - Buckner, Benjamin R. AU - Zhu, Meifang AU - Cavanagh, H. Dwight AU - Robertson, Danielle M. T2 - The Ocular Surface AB - To determine the ratio of IGFBP3:IGF-1 in normal and diabetic human tears, and in telomerase-immortalized human corneal epithelial cells (hTCEpi) cultured under elevated glucose conditions and to correlate these changes with total and phosphorylated levels of IGF-1R. Tear samples were collected noninvasively from diabetic subjects and non-diabetic controls; corneal sensitivity was assessed using a Cochet-Bonnet Aesthesiometer. Conditioned media were collected following culture of hTCEpi cells in normal (5 mM) and elevated (25 mM) glucose conditions; mannitol was used as an osmotic control. IGFBP3, IGF-1, and phosphorylated IGF-1R levels were assessed by ELISA. IGFBP3 and IGF-1R mRNA were assessed by real-time polymerase chain reaction (PCR). Total and phosphorylated IGF-1R expression in whole cell lysates was assessed by western blot. There was a 2.8-fold increase in IGFBP3 in diabetic tears compared to non-diabetic controls (P=0.006); IGF-1 levels were not significantly altered. No difference in corneal sensitivity was detected between groups. The concentration of IGFBP3 in tears was independent of IGF-1. Consistent with human tear measurements in vivo, IGFBP3 secretion was increased 2.2 fold (P<0.001) following culture of hTCEpi cells under elevated glucose conditions in vitro. Treatment with glucose and the mannitol control reduced IGFBP3 mRNA (P<0.001). Total IGF-1R levels were unchanged. The increase in the IGFBP3:IGF-1 ratio detected in diabetic tears compared to normal controls blocked phosphorylation of the IGF-1R by IGF-1 (P<0.001) when tested in vitro. Taken together, these in vivo and confirmatory in vitro findings suggest that the observed increase in IGFBP3 found in human tears may attenuate IGF-1R signaling in the diabetic cornea. A long-term increase in IGFBP3 may contribute to epithelial compromise and the pathogenesis of ocular surface complications reported in diabetes. DA - 2012/04// PY - 2012 DO - 10.1016/j.jtos.2012.01.004 DP - PubMed VL - 10 IS - 2 SP - 100 EP - 107 J2 - Ocul Surf LA - eng SN - 1542-0124 ST - Elevated IGFBP3 levels in diabetic tears L1 - https://europepmc.org/articles/pmc3322367?pdf=render L2 - http://www.ncbi.nlm.nih.gov/pubmed/22482470 KW - Adult KW - Blotting, Western KW - Cells, Cultured KW - Corneal Diseases KW - Diabetes Mellitus, Type 1 KW - Diabetes Mellitus, Type 2 KW - Enzyme-Linked Immunosorbent Assay KW - Epithelium, Corneal KW - Female KW - Humans KW - Insulin-Like Growth Factor Binding Protein 3 KW - Insulin-Like Growth Factor I KW - Male KW - Middle Aged KW - Real-Time Polymerase Chain Reaction KW - Receptor, IGF Type 1 KW - Tears ER - TY - JOUR TI - Early microvascular and neural changes in patients with type 1 and type 2 diabetes mellitus without clinical signs of diabetic retinopathy AU - Vujosevic, Stela AU - Muraca, Andrea AU - Alkabes, Micol AU - Villani, Edoardo AU - Cavarzeran, Fabiano AU - Rossetti, Luca AU - De Cillaʼ, Stefano T2 - Retina (Philadelphia, Pa.) AB - PURPOSE: To assess and compare early modifications in inner retinal layer thickness and optical coherence tomography angiography parameters in patients with diabetes mellitus (DM) Types 1 and 2 without clinical signs of diabetic retinopathy. METHODS: Ninety eyes of 90 subjects (24 Type 1 DM, 36 Type 2 DM, and 30 healthy controls) were prospectively evaluated with spectral domain OCT, swept-source OCT angiography, and color fundus photography (on the same day). Retinal nerve fiber layer, ganglion cell layer (GCL+), and nerve fiber layer + GCL+ (GCL++) thickness were automatically determined by the instrument in the 1, 3, and 6 central mm. On OCT angiography, the following parameters were evaluated: area of foveal avascular zone, number of focally dilated endings of the capillaries (detected only on OCT angiography), presence of regular/irregular foveal avascular zone, capillary loss, and capillary network irregularities in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). RESULTS: Ganglion cell layer+ (P = 0.0099) and GCL++ (P = 0.0367) were significantly thicker in DM Type 1 versus DM Type 2 in 1 central mm, after adjustment for age and DM duration. The area of foveal avascular zone was significantly larger in DM Type 1 versus controls in both SCP and DCP and in DM Type 1 versus Type 2 only in DCP (P < 0.05 for all); the number of focally dilated endings of the capillaries was higher in DM Type 1 versus controls in both SCP and DCP (P < 0.01 for all); and in DM Type 2 versus controls only in DCP (P = 0.007). Perifoveal capillary loss in SCP and inner retinal layer thickness had the highest correlation in both DM types. CONCLUSION: There are specific neural and microvascular modifications even before clinical signs of diabetic retinopathy in DM Types 1 and 2. Perifoveal capillary loss in the SCP is highly correlated with inner retinal layer. These data may help in characterization of patients at the preclinical stage of diabetic retinopathy. DA - 2019/03// PY - 2019 DO - 10.1097/IAE.0000000000001990 DP - PubMed VL - 39 IS - 3 SP - 435 EP - 445 J2 - Retina LA - eng SN - 1539-2864 L1 - https://air.unimi.it/retrieve/handle/2434/562182/1036294/Paper%20Angio-OCT%2012.05.2017.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/29206758 KW - Adult KW - Aged KW - Aged, 80 and over KW - Capillaries KW - Case-Control Studies KW - Cross-Sectional Studies KW - Diabetes Mellitus, Type 1 KW - Diabetes Mellitus, Type 2 KW - Diabetic Retinopathy KW - Female KW - Fovea Centralis KW - Humans KW - Male KW - Middle Aged KW - Prospective Studies KW - Retinal Ganglion Cells KW - Retinal Vessels KW - Young Adult ER - TY - JOUR TI - Differential reduction in corneal nerve fiber length in patients with type 1 or type 2 diabetes mellitus AU - Stem, Maxwell S. AU - Hussain, Munira AU - Lentz, Stephen I. AU - Raval, Nilesh AU - Gardner, Thomas W. AU - Pop-Busui, Rodica AU - Shtein, Roni M. T2 - Journal of diabetes and its complications AB - Aim To examine the relationship between corneal nerve fiber length (CNFL) and diabetic neuropathy (DN) status in patients with type 1 or type 2 diabetes mellitus (DM) Methods In this cross-sectional study, we examined 25 diabetic patients without DN, 10 patients with mild DN, 8 patients with severe DN, and 9 controls without diabetes. DN status was assigned based on a combination of clinical symptoms, signs, and electrophysiological testing. Patients underwent corneal confocal microscopy (CCM) of the sub-basal nerve plexus. Post-hoc analysis of the CCM images was performed to quantify the average CNFL, and ANOVA was used to assess for differences in CNFL. Results All 25 subjects without DN had type 1 DM, and subjects with DN had type 2 DM. Participants with severe DN had significantly lower CNFL (12.5 ± 6.1 mm/mm2) compared to controls (20.7 ± 2.2 mm/mm2) (p=0.009). However, lower CNFL was also found in participants with type 1 DM who did not have DN (15.1 ± 4.7 mm/mm2) relative to controls (p=0.033). Conclusions CCM of the sub-basal nerve plexus may be an indicator of early peripheral nerve degeneration in type 1 DM. Type of diabetes, in addition to degree of neuropathy, may influence the extent of corneal nerve damage. DA - 2014/// PY - 2014 DO - 10.1016/j.jdiacomp.2014.06.007 DP - PubMed Central VL - 28 IS - 5 SP - 658 EP - 661 J2 - J Diabetes Complications SN - 1056-8727 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4146399/ Y2 - 2021/03/02/01:40:05 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4146399/pdf/nihms606502.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4146399/ ER - TY - JOUR TI - Clinical evaluation of corneal changes after phacoemulsification in diabetic and non-diabetic cataract patients, a systematic review and meta-analysis AU - Tang, Yizhen AU - Chen, Xinyi AU - Zhang, Xiaobo AU - Tang, Qiaomei AU - Liu, Siyu AU - Yao, Ke T2 - Scientific Reports AB - Corneal endothelium morphological abnormalities result in fluid imbalance, stromal swelling, and loss of transparency, thus impairing visual function. Recently, growing number of studies have focused on diabetic corneal abnormalities after cataract surgery and its comparison with non-diabetic patients, the results remain conflicting. Thus, to evaluate the effect of phacoemulsification on the corneal properties in diabetic and non-diabetic patients, prospective studies were comprehensively searched through PubMed, EMBASE, and Cochrane databases updated to Jan 2017. A meta-analysis of the 13 identified studies was performed using weighted mean difference (WMD) and 95% confidence interval (CI). For the dynamic changes between preoperative and postoperative values, significant differences were identified between the two groups in endothelial cell density (ECD) and hexagon cells (HC%) at 1 day, 1 week, 1 month, and 3 months postoperatively, in central corneal thickness (CCT) at 1 month postoperatively, and in coefficient variation (CV) at 1 week and 1 month postoperatively. However, no significant differences were observed in CCT at 1 day, 1 week and 3 months postoperatively or in CV at 1 day and 3 months postoperatively. Diabetic corneas are more vulnerable to stress and trauma, resulting in greater morphological abnormalities and longer recovery time. DA - 2017/10/26/ PY - 2017 DO - 10.1038/s41598-017-14656-7 DP - PubMed Central VL - 7 J2 - Sci Rep SN - 2045-2322 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5658349/ Y2 - 2021/03/05/11:34:31 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5658349/pdf/41598_2017_Article_14656.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5658349/ ER - TY - JOUR TI - Retinopathy in Diabetes AU - Fong, Donald S. AU - Aiello, Lloyd AU - Gardner, Thomas W. AU - King, George L. AU - Blankenship, George AU - Cavallerano, Jerry D. AU - Ferris, Fredrick L. AU - Klein, Ronald T2 - Diabetes Care AB - Diabetic retinopathy is the most frequent cause of new cases of blindness among adults aged 20–74 years. During the first two decades of disease, nearly all patients with type 1 diabetes and >60% of patients with type 2 diabetes have retinopathy. In the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR), 3.6% of younger-onset patients (type 1 diabetes) and 1.6% of older-onset patients (type 2 diabetes) were legally blind. In the younger-onset group, 86% of blindness was attributable to diabetic retinopathy. In the older-onset group, in which other eye diseases were common, one-third of the cases of legal blindness were due to diabetic retinopathy. Diabetic retinopathy progresses from mild nonproliferative abnormalities, characterized by increased vascular permeability, to moderate and severe nonproliferative diabetic retinopathy (NPDR), characterized by vascular closure, to proliferative diabetic retinopathy (PDR), characterized by the growth of new blood vessels on the retina and posterior surface of the vitreous. Macular edema, characterized by retinal thickening from leaky blood vessels, can develop at all stages of retinopathy. Pregnancy, puberty, blood glucose control, hypertension, and cataract surgery can accelerate these changes. Vision-threatening retinopathy is rare in type 1 diabetic patients in the first 3–5 years of diabetes or before puberty. During the next two decades, nearly all type 1 diabetic patients develop retinopathy. Up to 21% of patients with type 2 diabetes have retinopathy at the time of first diagnosis of diabetes, and most develop some degree of retinopathy over time. Vision loss due to diabetic retinopathy results from several mechanisms. Central vision may be impaired by macular edema or capillary nonperfusion. New blood vessels of PDR and contraction of the accompanying fibrous tissue can distort the retina and lead to tractional retinal detachment, producing severe and often irreversible vision loss. In addition, the new blood vessels may bleed, adding the further … DA - 2004/01/01/ PY - 2004 DO - 10.2337/diacare.27.2007.S84 DP - care.diabetesjournals.org VL - 27 IS - suppl 1 SP - s84 EP - s87 LA - en SN - 0149-5992, 1935-5548 UR - https://care.diabetesjournals.org/content/27/suppl_1/s84 Y2 - 2021/03/05/13:54:59 L1 - https://care.diabetesjournals.org/content/diacare/27/suppl_1/s84.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/14693935 L2 - https://care.diabetesjournals.org/content/27/suppl_1/s84 KW - DCCT, Diabetes Control and Complications Trial KW - ETDRS, Early Treatment Diabetic Retinopathy Study KW - HRC, high-risk characteristic KW - NPDR, nonproliferative diabetic retinopathy KW - PDR, proliferative diabetic retinopathy KW - UKPDS, U.K. Prospective Diabetes Study KW - WESDR, Wisconsin Epidemiologic Study of Diabetic Retinopathy ER - TY - JOUR TI - Age-Related Changes in Central and Peripheral Corneal Thickness AU - Costantini, E. AU - Touzeau, O. AU - Gaujoux, T. AU - Basli, E. AU - Kopito, R. AU - Borderie, V. M. AU - Laroche, L. T2 - Investigative Ophthalmology & Visual Science DA - 2009/04/28/ PY - 2009 DP - iovs.arvojournals.org VL - 50 IS - 13 SP - 5107 EP - 5107 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - http://iovs.arvojournals.org/article.aspx?articleid=2367476 Y2 - 2021/03/05/22:41:18 L2 - https://iovs.arvojournals.org/article.aspx?articleid=2367476 ER - TY - JOUR TI - Behavior of corneal endothelial density over a lifetime AU - Abib, F. C. AU - Barreto Junior, J. T2 - Journal of Cataract and Refractive Surgery AB - PURPOSE: To define a behavioral model of corneal endothelial density over a lifetime, determine its values, construct a graphic representation, and show the probabilities of occurrence using modified prognosis ranges. SETTING: A private clinic in Brazil. METHODS: This retrospective study comprised 784 corneal specular microscopy examinations without regard to race, sex, or age and without a history or pathologies that would alter the endothelium. Endothelial density results were grouped by decades according to patient age. Projections of mean densities and standard deviations by decade were calculated by adjusting the model by variable. The probability of occurrence of the endothelial densities was calculated (P <.05). RESULTS: The endothelial density over time followed a decreasing linear model (correlation coefficient -0.993). As the endothelial density decreased, the standard deviation tended to increase. The probability of occurrence of an endothelial density of less than 2000 cells/mm(2) was higher from the seventh decade on. CONCLUSIONS: Knowing the representative values of endothelial density and the probabilities of occurrence over a lifetime can help surgeons determine the risk to the cornea of anterior segment surgery. It can also be useful in following eyes with disease affecting the endothelium and in preparing and evaluating corneal specular microscopy reports. DA - 2001/10// PY - 2001 DO - 10.1016/s0886-3350(01)00925-7 DP - PubMed VL - 27 IS - 10 SP - 1574 EP - 1578 J2 - J Cataract Refract Surg LA - eng SN - 0886-3350 L2 - http://www.ncbi.nlm.nih.gov/pubmed/11687354 KW - Adolescent KW - Adult KW - Aged KW - Aged, 80 and over KW - Aging KW - Cell Count KW - Child KW - Endothelium, Corneal KW - Humans KW - Middle Aged KW - Retrospective Studies ER - TY - JOUR TI - Age related changes in corneal morphological characteristics of healthy Pakistani eyes AU - Islam, Qamar Ul AU - Saeed, Muhammad Kamran AU - Mehboob, Mohammad Asim T2 - Saudi Journal of Ophthalmology AB - Purpose To determine the age related changes in corneal morphological characteristics in normal healthy adult Pakistani population. Methods Four hundred and sixty-four eyes of 232 healthy volunteers with ages between 10 and 80 years of either gender were included. Corneal endothelial cell density (CED), morphology and central corneal thickness (CCT) were evaluated in each subject with non-contact specular microscope (SP-3000 P, Topcon Corporation, Japan) and average of three readings per eye was used for final analysis. All the findings including demographic data, and corneal parameters were endorsed on a pre-devised proforma. Results Mean age of study population was 39.52 ± 18.09 years with 123 (53%) males and 109 (47%) females. Mean CED of study population was 2722.67 ± 349.67 cells/mm2, while mean CCT was 505.72 ± 32.82 µm. Corneal morphological parameters among various age groups showed statistically significant difference in all parameters (p < 0.01). Correlation statistics revealed that CED (r = −0.497, p < 0.01), CCT (r = −0.216, p < 0.01) and hexagonality (r = −0.397, p < 0.01) decreased significantly with increasing age, while average cell size (r = 0.492, p < 0.01) and CV of size (r = 0.454, p < 0.01) increased with age. Conclusion This study showed that CED in Pakistani eyes was less than that reported in Chinese eyes, higher than Portuguese, Iranian and Indian eyes and comparable to the values in Turkish, Nigerian and Thai eyes. DA - 2017/// PY - 2017 DO - 10.1016/j.sjopt.2017.02.009 DP - PubMed Central VL - 31 IS - 2 SP - 86 EP - 90 J2 - Saudi J Ophthalmol SN - 1319-4534 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5436377/ Y2 - 2021/03/06/13:03:47 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5436377/pdf/main.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5436377/ ER - TY - JOUR TI - Diabetes, Fasting Glucose, and the Risk of Glaucoma: A Meta-analysis AU - Zhao, Di AU - Cho, Juhee AU - Kim, Myung Hun AU - Friedman, David S. AU - Guallar, Eliseo T2 - Ophthalmology AB -

Topic

We performed a systematic review to summarize the association of diabetes and blood glucose levels with glaucoma, intraocular pressure (IOP), and ocular hypertension in the general population.

Clinical Relevance

Diabetes has been proposed as a risk factor for glaucoma, but epidemiologic studies have been inconsistent, and the association is still controversial. Furthermore, no systematic reviews evaluated other metabolic abnormalities, such as the metabolic syndrome, with the risk of glaucoma.

Methods

We identified the studies by searching the PubMed and EMBASE databases. We used inverse-variance weighted random-effects models to summarize relative risks across studies.

Results

We identified 47 studies including 2 981 342 individuals from 16 countries. The quality of evidence generally was higher in the cohort compared with case-control or cross-sectional studies. The pooled relative risk for glaucoma comparing patients with diabetes with those without diabetes was 1.48 (95% confidence interval [CI], 1.29–1.71), with significant heterogeneity across studies (I2 = 82.3%; P < 0.001). The risk of glaucoma increased by 5% (95% CI, 1%–9%) for each year since diabetes diagnosis. The pooled average difference in IOP comparing patients with diabetes with those without diabetes was 0.18 mmHg (95% CI, 0.09–0.27; I2 = 73.2%), whereas the pooled average increase in IOP associated with an increase in 10 mg/dl in fasting glucose was 0.09 mmHg (95% CI, 0.05–0.12; I2 = 34.8%).

Conclusions

Diabetes, diabetes duration, and fasting glucose levels were associated with a significantly increased risk of glaucoma, and diabetes and fasting glucose levels were associated with slightly higher IOP.

DA - 2015/01/01/ PY - 2015 DO - 10.1016/j.ophtha.2014.07.051 DP - www.aaojournal.org VL - 122 IS - 1 SP - 72 EP - 78 J2 - Ophthalmology LA - English SN - 0161-6420, 1549-4713 ST - Diabetes, Fasting Glucose, and the Risk of Glaucoma UR - https://www.aaojournal.org/article/S0161-6420(14)00697-6/abstract Y2 - 2021/03/12/09:06:51 L1 - http://www.aaojournal.org/article/S0161642014006976/pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/25283061 L2 - https://www.aaojournal.org/article/S0161-6420(14)00697-6/fulltext ER - TY - JOUR TI - Human corneal thickness and its impact on intraocular pressure measures: a review and meta-analysis approach AU - Doughty, M. J. AU - Zaman, M. L. T2 - Survey of Ophthalmology AB - We determined the "normal" central corneal thickness (CCT) value in human corneas based on reported literature values for within-study average CCT values, and used this as a reference to assess the reported impact of physiological variables (especially age and diurnal effects), contact lens wear, pharmaceuticals, ocular disease, and ophthalmic surgery on CCT. With the expected CCT and its variance defined, it should be possible to determine the potential impact of differences in CCT in intraocular pressure (IOP) assessments, especially by applanation tonometry, using a meta-analysis approach. Some 600 sets of CCT data were identified from the worldwide literature over the period of 1968 through mid-1999, of which 134 included IOP measures as well. The within-study average CCT values and reported variance (SD) was noted along with the number of eyes and any special characteristics, including probable ethnic origin of the study subjects. Various sets of data were subjected to statistical analyses. From 300 data sets from eyes designated as normal, the group-averaged CCT was 0.534 mm. From 230 data sets where interindividual variance was reported, the group-averaged CCT was 0.536 mm (median 0.536 mm; average SD of 0. 031 mm, average coefficient of variation = 5.8%). Overall, studies using slit-lamp-based pachometry have reported marginally lower CCT values (average 0.530 mm, average SD 0.029 mm) compared to ultrasound-based studies (average 0.544, average SD 0.034 mm), which perhaps reflects the type of individual studied (non-surgical vs. pre-surgical patients) rather than the technique itself. A slight chronological increase in reported average CCT values (approximately 0.006 mm/decade) was evident, but a substantial chronological increase was evident for ultrasound pachometry studies (approximately 0.015 mm/decade). Within the meta-analysis-generated average and variance, age had no obvious impact on CCT measures for *whites, although an age-related decline in CCT is evident for non-whites. Any diurnal effects are likely concealed within the expected variance in CCT. Contact lens wear and pharmaceuticals generally produced changes in CCT that were well within the expected variance in CCT. Of the ocular diseases, only those associated with collagen disorders (including keratoconus) or endothelial-based corneal dystrophies (e.g., Fuchs) were likely to result in decreases or increases, respectively, of CCT beyond the normal variance. Routine contact lens wear and diseases such as diabetes seem unlikely to produce changes in CCT of a magnitude that would justify pachometry as a monitoring method beyond routine slit-lamp evaluation. Increases in CCT beyond the expected variance were reported after a range of intraocular surgeries (cataract operations, penetrating keratoplasty), whereas photorefractive surgery produces a measurable decrease in CCT. A meta-analysis of possible association between CCT and IOP measures of 133 data sets, regardless of the type of eyes assessed, revealed a statistically significant correlation; a 10% difference in CCT would result in a 3. 4 +/- 0.9 mm Hg difference in IOP (P 7 days was associated with poor transplant suitability (P = .04). Donors with COPD and donors who were mechanically ventilated exhibited lower cell counts (P < .001, P < .01, respectively). Longer ventilation led to reduced endothelial cell density: ventilation time >7 days (−46.5 cells/mm2, P < .001) and >30 days (−101.4 cells/mm2, P = .02). Limitations of the study included the retrospective nature, dataset obtained from a single eye bank, and medical history documentation completed by eye bank technicians. Conclusions A high proportion of cornea donors have respiratory disease prior to donation. Ventilation time >7 days affected transplant suitability but the presence of COPD did not. Donors with COPD and donors who were mechanically ventilated had reduced cell counts. Longer ventilation times lead to increased cell loss. The presence of respiratory disease may affect tissue oxygenation and endothelial cell health. DA - 2017/11/01/ PY - 2017 DO - 10.1016/j.ajo.2017.08.023 DP - ScienceDirect VL - 183 SP - 65 EP - 70 J2 - American Journal of Ophthalmology LA - en SN - 0002-9394 UR - https://www.sciencedirect.com/science/article/pii/S000293941730377X Y2 - 2021/03/15/16:23:06 L2 - https://www.sciencedirect.com/science/article/abs/pii/S000293941730377X ER - TY - JOUR TI - A study of corneal endothelial changes in soft contact lens wearers using non-contact specular microscopy AU - Magdum, Renu M. AU - Mutha, Neha AU - Maheshgauri, Rupali T2 - Medical Journal of Dr. D.Y. Patil University AB - Aim: To study the corneal endothelial changes after soft contact lens wear, to correlate these changes with the duration of soft contact lens wear, and to study the pattern of use and preferences of contact lens among young adults. Materials and Methods: This observational study was carried out in 100 eyes of 50 soft contact lens users aged between 19 and 27 years. Both eyes of 50 medical students who had never worn contact lenses served as controls. Data from each subject were collected using a structured questionnaire of 24 items that included demographic profile, pattern of contact lens use, symptoms, brand name, number of years worn, and hours of daily wear. These data were analyzed using Chi square for association. Specular microscopy was done using TOPCON SP-3000P. Computerized morphometry was used to evaluate central corneal thickness, size, shape, mean cellular density, hexagonality, coefficient of variation, and polymegathism of the corneal cells . Results: It was found that central corneal thickness was 0.532 ± 0.0309 mm in lens users and 0.514 ± 0.03 mm in controls, cell density was 2570.91 ± 432.06 cells/mm 2 in lens users and 2723.17 ± 327.64 cells/mm 2 in controls, while hexagonality was 54.81 ± 39.72% in lens users and 67.65 ± 36.49% in controls. Conclusion: Despite the known effects of long duration of soft contact lens use on corneal endothelial cell morphology, this study could not draw a significant correlation between them. However, a significant difference was found in the corneal endothelial thickness, cell density, and hexagonality. Among the soft contact lens users, 62% used soft disposable type while 38% used soft extended wear contact lens. Contact lenses were preferred over spectacles for better cosmetic appearance, comfort, and wider visual field. DA - 2013/01/07/ PY - 2013 DO - 10.4103/0975-2870.114645 DP - www.mjdrdypu.org VL - 6 IS - 3 SP - 245 LA - en SN - 0975-2870 UR - https://www.mjdrdypu.org/article.asp?issn=0975-2870;year=2013;volume=6;issue=3;spage=245;epage=249;aulast=Magdum;type=0 Y2 - 2021/03/15/16:59:08 L2 - https://www.mjdrdypu.org/article.asp?issn=0975-2870;year=2013;volume=6;issue=3;spage=245;epage=249;aulast=Magdum ER - TY - ELEC TI - Corneal endothelial cell density in glaucoma. - Abstract - Europe PMC UR - https://europepmc.org/article/med/9143804 Y2 - 2021/03/15/17:14:55 L2 - https://europepmc.org/article/med/9143804 ER - TY - JOUR TI - Reduced Corneal Endothelial Cell Density in Patients with Dry Eye Disease AU - Kheirkhah, Ahmad AU - Saboo, Ujwala S. AU - Abud, Tulio B. AU - Dohlman, Thomas H. AU - Arnoldner, Michael A. AU - Hamrah, Pedram AU - Dana, Reza T2 - American journal of ophthalmology AB - To evaluate corneal endothelial cell density (ECD) in patients with dry eye disease (DED) compared to an age-matched control group.Cross-sectional, controlled studyThis study included 90 eyes of 45 patients with moderate-to-severe DED (53.7 ± ... DA - 2015/06// PY - 2015 DO - 10.1016/j.ajo.2015.03.011 DP - www.ncbi.nlm.nih.gov VL - 159 IS - 6 SP - 1022 LA - en UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4427236/ Y2 - 2021/03/15/18:12:02 L1 - https://dash.harvard.edu/bitstream/1/34854273/1/nihms678719.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/25782347 L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4427236/ ER - TY - JOUR TI - Fixed effects and variance components estimation in three-level meta-analysis AU - Konstantopoulos, Spyros T2 - Research Synthesis Methods AB - Meta-analytic methods have been widely applied to education, medicine, and the social sciences. Much of meta-analytic data are hierarchically structured because effect size estimates are nested within studies, and in turn, studies can be nested within level-3 units such as laboratories or investigators, and so forth. Thus, multilevel models are a natural framework for analyzing meta-analytic data. This paper discusses the application of a Fisher scoring method in two-level and three-level meta-analysis that takes into account random variation at the second and third levels. The usefulness of the model is demonstrated using data that provide information about school calendar types. sas proc mixed and hlm can be used to compute the estimates of fixed effects and variance components. Copyright © 2011 John Wiley & Sons, Ltd. DA - 2011/03// PY - 2011 DO - 10.1002/jrsm.35 DP - PubMed VL - 2 IS - 1 SP - 61 EP - 76 J2 - Res Synth Methods LA - eng SN - 1759-2879 L1 - https://www.econstor.eu/bitstream/10419/51903/1/668199628.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/26061600 KW - effect sizes KW - meta-analysis KW - multilevel models KW - variance components ER - TY - JOUR TI - Conducting Meta-Analyses in R with the metafor Package AU - Viechtbauer, Wolfgang T2 - Journal of Statistical Software DA - 2010/08/05/ PY - 2010 DO - 10.18637/jss.v036.i03 DP - www.jstatsoft.org VL - 36 IS - 1 SP - 1 EP - 48 LA - en SN - 1548-7660 UR - https://www.jstatsoft.org/index.php/jss/article/view/v036i03 Y2 - 2021/03/26/22:53:47 L1 - https://www.jstatsoft.org/index.php/jss/article/view/v036i03/v36i03.pdf L2 - https://www.jstatsoft.org/article/view/v036i03 ER - TY - ELEC TI - R: A language and environment for statistical computing. R Foundation for Statistical Computing AU - R Core Team (2020) AB - R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. LA - en M3 - Methodology Reference UR - https://www.eea.europa.eu/data-and-maps/indicators/oxygen-consuming-substances-in-rivers/r-development-core-team-2006 Y2 - 2021/03/26/23:08:22 L2 - https://www.eea.europa.eu/data-and-maps/indicators/oxygen-consuming-substances-in-rivers/r-development-core-team-2006 ER - TY - JOUR TI - Corneal endothelial cell changes in diabetics versus age group matched nondiabetics after manual small incision cataract surgery AU - Kudva, Ajay A. AU - Lasrado, Adeline S. AU - Hegde, Sudhir AU - Kadri, Rajani AU - Devika, P. AU - Shetty, Akansha T2 - Indian Journal of Ophthalmology AB -
Purpose: To assess and compare the endothelial cell changes after manual small incision cataract surgery (SICS) in diabetic patients versus age group matched non-diabetic patients. Methods: This comparative prospective observational follow-up study included 54 diabetic patients and 52 control patients without diabetes who underwent manual SICS. Preoperative, one day, one week, one month and three months post-surgery assessments of corneal endothelial cell changes were done using specular microscopy. Data analysis was performed using SPSS software (version 20.0, SPSS, Inc.). Mann–Whitney U test was used to compare the data between the test group and control group. Results: There was drop in the endothelial density in both the groups postoperatively, with the mean percentage of endothelial loss at three months post- surgery being 27.5% in diabetics and 18.3% in controls. There was also a significant increase in central corneal thickness and coefficient of variance in diabetics as compared to controls at every follow up one day, one week, one month and three months. The percentage of hexagonality was statistically significant at post-operative three months. Conclusion: The diabetic endothelium was found to be under greater metabolic stress and had less functional reserve after manual SICS than the normal corneal endothelium.
DA - 2020/01/01/ PY - 2020 DO - 10.4103/ijo.IJO_406_19 DP - www.ijo.in VL - 68 IS - 1 SP - 72 LA - en SN - 0301-4738 UR - https://www.ijo.in/article.asp?issn=0301-4738;year=2020;volume=68;issue=1;spage=72;epage=76;aulast=Kudva;type=0 Y2 - 2021/03/29/10:13:00 L2 - http://www.ncbi.nlm.nih.gov/pubmed/31856472 L2 - https://www.ijo.in/article.asp?issn=0301-4738;year=2020;volume=68;issue=1;spage=72;epage=76;aulast=Kudva ER - TY - JOUR TI - Aging and corneal layers: an in vivo corneal confocal microscopy study AU - Gambato, Catia AU - Longhin, Evelyn AU - Catania, Anton Giulio AU - Lazzarini, Daniela AU - Parrozzani, Raffaele AU - Midena, Edoardo T2 - Graefe's Archive for Clinical and Experimental Ophthalmology AB - To describe age-related changes of different corneal layers using a quantitative analysis of in vivo corneal confocal microscopy. DA - 2015/02/01/ PY - 2015 DO - 10.1007/s00417-014-2812-2 DP - Springer Link VL - 253 IS - 2 SP - 267 EP - 275 J2 - Graefes Arch Clin Exp Ophthalmol LA - en SN - 1435-702X ST - Aging and corneal layers UR - https://doi.org/10.1007/s00417-014-2812-2 Y2 - 2021/04/03/12:31:21 L1 - http://link.springer.com/content/pdf/10.1007%2Fs00417-014-2812-2.pdf ER - TY - JOUR TI - Age-related differences in the normal human cornea: a laser scanning in vivo confocal microscopy study AU - Niederer, R. L. AU - Perumal, D. AU - Sherwin, T. AU - McGhee, C. N. J. T2 - The British Journal of Ophthalmology AB - AIMS: To quantify and establish baseline normative data for age-related differences in cellular and innervation density in the normal, healthy, human cornea using laser scanning in vivo confocal microscopy. METHODS: Cross-sectional study of 85 normal subjects assessed via corneal topography and laser scanning in vivo confocal microscopy. RESULTS: Mean age was 38+/-16 years (range 18-87 years) and 60% of subjects were female. Anterior keratocyte density declined by 0.9% per year (r = -0.423, p<0.001), posterior keratocyte density declined by 0.3% per year (r = -0.250, p = 0.021) and endothelial cell density declined by 0.5% per year (r = -0.615, p<0.001). Sub-basal nerve fibre density declined by 0.9% per year (r = -0.423, p<0.001). No association was observed between age and basal epithelial cell density, or between age and central corneal thickness, corneal astigmatism or horizontal corneal diameter (p>0.05). No association was observed between subject gender and corneal cell or innervation density. CONCLUSIONS: Using laser scanning in vivo confocal microscopy this study highlights a significant, and relatively linear, reduction in keratocyte and endothelial cell density with increasing subject age. Interestingly, corneal sub-basal nerve fibre density also significantly decreases with increasing age. In vivo laser scanning confocal microscopy provides a safe, non-invasive method for the establishment of normative data and assessment of alterations in human corneal microstructure following surgery or disease processes. DA - 2007/09// PY - 2007 DO - 10.1136/bjo.2006.112656 DP - PubMed VL - 91 IS - 9 SP - 1165 EP - 1169 J2 - Br J Ophthalmol LA - eng SN - 0007-1161 ST - Age-related differences in the normal human cornea L1 - https://europepmc.org/articles/pmc1954900?pdf=render L2 - http://www.ncbi.nlm.nih.gov/pubmed/17389741 KW - Adolescent KW - Adult KW - Aged KW - Aged, 80 and over KW - Aging KW - Cell Count KW - Cornea KW - Corneal Topography KW - Endothelium, Corneal KW - Epithelium, Corneal KW - Female KW - Humans KW - Image Processing, Computer-Assisted KW - Laser Scanning Cytometry KW - Male KW - Microscopy, Confocal KW - Middle Aged KW - Nerve Fibers ER - TY - JOUR TI - Loss of N-Cadherin from the Endothelium Causes Stromal Edema and Epithelial Dysgenesis in the Mouse Cornea AU - Vassilev, Vassil S. AU - Mandai, Michiko AU - Yonemura, Shigenobu AU - Takeichi, Masatoshi T2 - Investigative Ophthalmology & Visual Science DA - 2012/10/01/ PY - 2012 DO - 10.1167/iovs.12-9949 DP - iovs.arvojournals.org VL - 53 IS - 11 SP - 7183 EP - 7193 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - https://iovs.arvojournals.org/article.aspx?articleid=2127685 Y2 - 2021/04/03/17:34:44 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/932976/i1552-5783-53-11-7183.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2127685 ER - TY - JOUR TI - Experimental diabetes mellitus down-regulates large-conductance Ca2+-activated K+ channels in cerebral artery smooth muscle and alters functional conductance AU - Wang, Yan AU - Zhang, Hong-Tao AU - Su, Xing-Li AU - Deng, Xiu-Ling AU - Yuan, Bing-Xiang AU - Zhang, Wei AU - Wang, Xin-Feng AU - Yang, Yu-Bai T2 - Current Neurovascular Research AB - Cerebral vascular dysfunction and associated vascular complications often develop over time in type-2 diabetes, but the underlying mechanisms are not wholly understood. The aim of the present study was to investigate whether large-conductance Ca(2+)-activated K(+) (BKCa) channels in cerebral artery smooth muscle cells (CASMCs) were impaired in experimental model of type-2 diabetes, and the changes could account for cerebral vascular complication in type-2 diabetes. Sprague-Dawley rats were fed with high fat and glucose diet for 8 weeks and then injected with streptozotocin (STZ/30 mg/kg i.p.). Three months after injection of STZ, the alterations of BKCa channels were assessed by using multi-myograph system, patch-clamp, RT-PCR and Western blot. Our results show that the model is characterized by insulin resistance, hyperglycaemia, hyperlipidemia and moderate hypertension, which resembles the clinical manifestation of patients with typre-2 diabetes. Inhibition of BKCa channels with 1 mM tetraethylammonium (TEA) or 1 microM paxilline (PAX) causes smaller constriction in type-2 diabetic cerebral basilar arteries than control arteries. The contractile efficacy of 5-Hydroxytryptamine (5-HT) is substantially reduced by TEA or PAX pretreatment in control > diabetic basilar artery rings. The response to 5-HT in diabetic basilar artery rings is higher than that of control artery rings after activation of BKCa channels with NS1619. The whole-cell K(+) currents are significantly decreased in type-2 diabetic CASMCs compared to control, and the sensitivity of BKCa channels to voltage, the specific inhibitor and opener are all diminished in diabetic CASMCs. The expression of BKCa channel beta1, but not alpha-subunits is markedly reduced at both of mRNA and protein levels in endothelial-denudated cerebral arteries. In conclusion, type-2 diabetes downregulates BKCa channel beta1-subunits in CASMCs, resulting in reduced activity of BKCa channel, increased vascular tone and blood pressure, thereby contributing to cerebral vascular complication in type-2 diabetes. DA - 2010/05// PY - 2010 DO - 10.2174/156720210791184925 DP - PubMed VL - 7 IS - 2 SP - 75 EP - 84 J2 - Curr Neurovasc Res LA - eng SN - 1875-5739 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20334613 KW - Animals KW - Benzimidazoles KW - Blood Glucose KW - Body Weight KW - Cerebral Arteries KW - Diabetes Mellitus, Experimental KW - Disease Models, Animal KW - Dose-Response Relationship, Drug KW - Down-Regulation KW - Electromyography KW - In Vitro Techniques KW - Indoles KW - Large-Conductance Calcium-Activated Potassium Channels KW - Male KW - Membrane Potentials KW - Models, Biological KW - Muscle Contraction KW - Muscle, Smooth KW - Patch-Clamp Techniques KW - Potassium Channel Blockers KW - Rats KW - Rats, Sprague-Dawley KW - Serotonin KW - Streptozocin KW - Tetraethylammonium ER - TY - JOUR TI - KCa and Ca2+ channels: The complex thought AU - Guéguinou, Maxime AU - Chantôme, Aurélie AU - Fromont, Gaëlle AU - Bougnoux, Philippe AU - Vandier, Christophe AU - Potier-Cartereau, Marie T2 - Biochimica et Biophysica Acta (BBA) - Molecular Cell Research T3 - Calcium Signaling in Health and Disease AB - Potassium channels belong to the largest and the most diverse super-families of ion channels. Among them, Ca2+-activated K+ channels (KCa) comprise many members. Based on their single channel conductance they are divided into three subfamilies: big conductance (BKCa), intermediate conductance (IKCa) and small conductance (SKCa; SK1, SK2 and SK3). Ca2+ channels are divided into two main families, voltage gated/voltage dependent Ca2+ channels and non-voltage gated/voltage independent Ca2+ channels. Based on their electrophysiological and pharmacological properties and on the tissue where there are expressed, voltage gated Ca2+ channels (Cav) are divided into 5 families: T-type, L-type, N-type, P/Q-type and R-type Ca2+. Non-voltage gated Ca2+ channels comprise the TRP (TRPC, TRPV, TRPM, TRPA, TRPP, TRPML and TRPN) and Orai (Orai1 to Orai3) families and their partners STIM (STIM1 to STIM2). A depolarization is needed to activate voltage-gated Ca2+ channels while non-voltage gated Ca2+ channels are activated by Ca2+ depletion of the endoplasmic reticulum stores (SOCs) or by receptors (ROCs). These two Ca2+ channel families also control constitutive Ca2+ entries. For reducing the energy consumption and for the fine regulation of Ca2+, KCa and Ca2+ channels appear associated as complexes in excitable and non-excitable cells. Interestingly, there is now evidence that KCa–Ca2+ channel complexes are also found in cancer cells and contribute to cancer-associated functions such as cell proliferation, cell migration and the capacity to develop metastases. This article is part of a Special Issue entitled: Calcium signaling in health and disease. Guest Editors: Geert Bultynck, Jacques Haiech, Claus W. Heizmann, Joachim Krebs, and Marc Moreau. DA - 2014/10/01/ PY - 2014 DO - 10.1016/j.bbamcr.2014.02.019 DP - ScienceDirect VL - 1843 IS - 10 SP - 2322 EP - 2333 J2 - Biochimica et Biophysica Acta (BBA) - Molecular Cell Research LA - en SN - 0167-4889 ST - KCa and Ca2+ channels UR - https://www.sciencedirect.com/science/article/pii/S0167488914000834 Y2 - 2021/04/05/10:39:10 L1 - https://pdf.sciencedirectassets.com/271024/1-s2.0-S0167488914X0008X/1-s2.0-S0167488914000834/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjELr%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIATi8LziMqdnWo1MDIyKaMw4sFtJm1K079r%2BOWeOGImHAiEA%2Fdw3X29kdTZ1jRoPjpPEM8XO6hMCYN6knqkfr51cFgEqtAMIExADGgwwNTkwMDM1NDY4NjUiDJ0O9Zs3EsGpDuJy6CqRA2ZCQRYJLme9bjg2AtoAelhtntg2SQyI5zS%2B80uXJTfpvDcDvpmYff9DNcaQsMrKVib%2Fnr2l7UzSkncuFTtTEz%2BF9r24DyrabXhNVK37UmRQDpifR8lUMoRjBtBWzroyIfr1RIS8YwQmj1NgS8NIrDePCRzOp56AozzY8jAp418n0K7NgMt71fMHUihuKs93v%2FNu7o7XvsZbGDzDhJgUYgUyYlF7VNL7coFRMeAiryZfKZYIo%2BR70JM%2F0KJ7ETSgJNeBxFmTBcxQvHei2v2J1o7LQSTm6RTG0TeleWoK4lkppRwq7KBH9GAgVVZtfvma8LUAOT7Zyz8uHLCq0oHK7IwUDFsVeqVPyJH7vyJziD1YkQjxN%2FBtezOYiHHcCgCw281Dvj%2F2qh2DsppGmRVQm6ufJDYl3wUwePvHXPGR0ea1s8aAiUClVfT2P95v8B%2F0OHzOamKXIIZmYywHpLBkZ14%2B55pS7LuFC9gavSSLVykTLKKRd5WKmqno6FJRL3T2xw%2FJLiUGD87d6Ut3FiQHeghQMJy1q4MGOusB3vFDMib0ZIQL7JUK9y264TopjH9mMdqQBwLYUGdaueobet%2FJ0uMtEmnGHxID4pnHWPWwFBRgfM0n%2FdvVy1pWqgIkCvTjHndYoSjyrNWhYfmWPmN3k04CBsujA6l5I06KmEobcFA1NCqN61GqxHCw5HzbH9ymYTXDI7u2FXjReFrFAxDvz9HnribC8%2F0jyLuLDJpi88meBB3kyCwzetAaRU6yfFvXINZGCWjBGYOhHiXZR5opc8ipCGKNit59%2Fq3U94Yz3m4E6708g6x%2FHEZ56JjswyNq7DRZh4BPf%2F%2FTAwSK2P1xUhTnhE87rg%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210405T103910Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYVUCWT6JJ%2F20210405%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=a2e5974514297d068e5f5aafe8da4173452911441dab0948deec2394ab0eaf8c&hash=ee8405a4c54479581eb1429bd8e0cfde8517f939037c7780cb46dab8c70f3d0f&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0167488914000834&tid=spdf-61e5578f-edbb-4976-b0b2-8fa233f7a3a6&sid=6cd69d4313869348823b179617409ca3e39fgxrqa&type=client L2 - https://www.sciencedirect.com/science/article/pii/S0167488914000834 KW - Ca channels KW - Cancer KW - KCa channels KW - Orai KW - SOC KW - TRP ER - TY - JOUR TI - Sodium-Activated Potassium Channels Are Functionally Coupled to Persistent Sodium Currents AU - Hage, Travis A. AU - Salkoff, Lawrence T2 - The Journal of Neuroscience AB - We report a novel coupled system of sodium-activated potassium currents (IKNa) and persistent sodium currents (INaP), the components of which are widely distributed throughout the brain. Its existence and importance has not been previously recognized. Although IKNa was known to exist in many cell types, the source of Na+ which activates IKNa remained a mystery. We now show in single membrane patches generated from the somas of rat neurons that sodium influx through INaP is sufficient for activation of KNa channels, without substantial contribution from the transient sodium current or bulk [Na+]i. INaP was found to be active at cell membrane resting potentials, a finding that may explain why IKNa can be evoked from negative holding potentials. These results show an unanticipated role for INaP in activating a negative feedback system countering the excitable effects INaP; the interrelatedness of INaP and IKNa suggests new ways neurons can tune their excitability. DA - 2012/02/22/ PY - 2012 DO - 10.1523/JNEUROSCI.5088-11.2012 DP - PubMed Central VL - 32 IS - 8 SP - 2714 EP - 2721 J2 - J Neurosci SN - 0270-6474 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3319674/ Y2 - 2021/04/05/14:03:58 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3319674/pdf/zns2714.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3319674/ ER - TY - JOUR TI - Down-regulation of the Small Conductance Calcium-activated Potassium Channels in Diabetic Mouse Atria* AU - Yi, Fu AU - Ling, Tian-You AU - Lu, Tong AU - Wang, Xiao-Li AU - Li, Jingchao AU - Claycomb, William C. AU - Shen, Win-Kuang AU - Lee, Hon-Chi T2 - Journal of Biological Chemistry AB - The small conductance Ca2+-activated K+ (SK) channels have recently been found to be expressed in the heart, and genome-wide association studies have shown that they are implicated in atrial fibrillation. Diabetes mellitus is an independent risk factor of atrial fibrillation, but the ionic mechanism underlying this relationship remains unclear. We hypothesized that SK channel function is abnormal in diabetes mellitus, leading to altered cardiac electrophysiology. We found that in streptozotocin-induced diabetic mice, the expression of SK2 and SK3 isoforms was down-regulated by 85 and 92%, respectively, whereas that of SK1 was not changed. SK currents from isolated diabetic mouse atrial myocytes were significantly reduced compared with controls. The resting potentials of isolated atrial preparations were similar between control and diabetic mice, but action potential durations were significantly prolonged in the diabetic atria. Exposure to apamin significantly prolonged action potential durations in control but not in diabetic atria. Production of reactive oxygen species was significantly increased in diabetic atria and in high glucose-cultured HL-1 cells, whereas exposure of HL-1 cells in normal glucose culture to H2O2 reduced the expression of SK2 and SK3. Tyrosine nitration in SK2 and SK3 was significantly increased by high glucose culture, leading to accelerated channel turnover. Treatment with Tiron prevented these changes. Our results suggest that increased oxidative stress in diabetes results in SK channel-associated electrical remodeling in diabetic atria and may promote arrhythmogenesis. DA - 2015/03/13/ PY - 2015 DO - 10.1074/jbc.M114.607952 DP - ScienceDirect VL - 290 IS - 11 SP - 7016 EP - 7026 J2 - Journal of Biological Chemistry LA - en SN - 0021-9258 UR - https://www.sciencedirect.com/science/article/pii/S0021925820767797 Y2 - 2021/04/05/20:57:36 L1 - https://pdf.sciencedirectassets.com/778417/1-s2.0-S0021925820X66804/1-s2.0-S0021925820767797/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEMX%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIQDWmNIrzl9VhvXmJb2%2FMs5HDEoUxWvcp9zVA67w3HTLlQIgbD%2Bfrslm2yk8LLtRKjIuxNXQXv7jxGDc%2BcQvFUDj3RgqtAMIHhADGgwwNTkwMDM1NDY4NjUiDJ8hvOVEbBUVuvaQJSqRA8%2FXbvGtQQZNj5DRvG13W4dOHRRVPf%2BGo3krHfzEJgFeX1%2F%2FgQoSMeUqS6x7EeyaA3x%2F7nb45szosaEEAgUr6n%2BUuPF%2F2WTWect%2FN%2Bf1u867BIAW6huiNqmh%2F8QkFc9K%2FU%2BvF%2F3szSy5B%2BHY5CUP8WyugynRZE%2F%2F9dT%2B53zUakGYE15Cj6Qnwn5iF8eW5TTB%2FkL8c5K8mmU%2F%2FP1N1weZ0esb5g0ljkhCxYZbGMmnOJUpKQsI3vJWnn85zM9mtMkkGedHS5YITgeTsK%2FvNyOf8Emz0H2jwJod3RRh7wCA9vW1cCX0vQuec0CB9f8wfzKlyWNynOYKf603lHGANifDj81JaGqJlLjDbLY%2FJHiEBdW7GM8VYT0ABd6vCJ6OW5dvM1wJd4t9nbS6L4V4nPQEgJDyp3KG6Tz25qtJhVB9vMJohD8ieOkCeJUeG7HvrRJ8UiVVaMCJ9ZGjq8iSn0Q7cuFNz5%2BoBWjL1DrHUAVrL7Vzjp2xWkn2lDKY%2B4SkwQQ5kFuFwVj3j43GCYdMw9tY%2B6EjMMnvrYMGOusBZ3C8KLKbVO5nSsaDo4eNfE%2B%2Fsa3AiQRnu0G%2Fwf7Gw8VO1QQOfoqtNKXmftUEbChFsy0T%2BRUGKAtfVHlYUgrX%2FEdxsDUSSybZd8QiJ%2F%2FS0SFvPGxLSw%2F3qNBtCPcIu9dBv1Az2Msm15QSnPNepNQ0DagZ5IWV4BNRmC4DaAtMf0SSyAXnZEvDcC7zPiOIofNotv1E400MBdJbt9wJJS9fdU5bpZyC22wbCyt0eD22%2FQq3gN42p1zcdOsOdNKmKjrsdU%2BUHmN291zmS3BN2qAxjGWv1f1Up4M%2B8gFKl0WtWtc3vA4kYXDIeHcnbQ%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210405T205735Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYUG6M3IGR%2F20210405%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=53dcb86dbdd1fce20df0fe679ae8552f3b0e0e7f4c57ea0b13c0d2192ff297bb&hash=4e46e6d906d647ea5589e086415604943958cdf689df3cfee13366482913d0b8&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0021925820767797&tid=spdf-c0e53838-d038-4be4-bd44-0b4da050619e&sid=6cd69d4313869348823b179617409ca3e39fgxrqa&type=client L2 - https://www.sciencedirect.com/science/article/pii/S0021925820767797 KW - Cardiomyocyte KW - Diabetes KW - HL-1 Cells KW - Mouse KW - Oxidative Stress KW - Patch Clamp KW - Potassium Channel KW - SK Channels ER - TY - JOUR TI - Advanced glycation end products impair K(Ca)3.1- and K(Ca)2.3-mediated vasodilatation via oxidative stress in rat mesenteric arteries AU - Zhao, Li-Mei AU - Wang, Yan AU - Ma, Xiao-Zhen AU - Wang, Nan-Ping AU - Deng, Xiu-Ling T2 - Pflugers Archiv: European Journal of Physiology AB - The present study was designed to investigate the role of advanced glycation end products (AGEs) in intermediate-conductance and small-conductance Ca(2+)-activated potassium channels (KCa3.1 and KCa2.3)-mediated relaxation in rat resistance arteries and the underlying mechanism. The endothelial function of mesenteric arteries was assessed with the use of wire myography. Expression levels of KCa3.1 and KCa2.3 were measured by using Western blot. Reactive oxygen species (ROS) were measured by using dihydroethidium and 2', 7'-dichlorofluorescein diacetate. KCa3.1 and KCa2.3-mediated vasodilatation responses to acetylcholine and NS309 (opener of KCa3.1 and KCa2.3) were impaired by incubation of the third-order mesenteric arteries from normal rats with AGEs (200 μg ml(-1) for 3 h). In cultured human umbilical vein endothelial cells (HUVECs), AGEs increased ROS level and decreased the protein expression of KCa3.1 and KCa2.3. Antioxidant alpha lipoic acid restored the impairment in both vasodilatation function and expression of KCa3.1 and KCa2.3. H2O2 could mimic the effect of AGEs on the protein expression of KCa3.1 and KCa2.3 in cultured HUVECs. These results demonstrate for the first time that AGEs impaired KCa3.1 and KCa2.3-mediated vasodilatation in rat mesenteric arteries via downregulation of both KCa3.1 and KCa2.3, in which the enhanced oxidative stress was involved. DA - 2014/02// PY - 2014 DO - 10.1007/s00424-013-1324-y DP - PubMed VL - 466 IS - 2 SP - 307 EP - 317 J2 - Pflugers Arch LA - eng SN - 1432-2013 L2 - http://www.ncbi.nlm.nih.gov/pubmed/23873353 KW - Alkanes KW - Animals KW - Glycation End Products, Advanced KW - Human Umbilical Vein Endothelial Cells KW - Humans KW - In Vitro Techniques KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Male KW - Mesenteric Arteries KW - NG-Nitroarginine Methyl Ester KW - Oxidative Stress KW - Pyrazoles KW - Quinolinium Compounds KW - Rats KW - Rats, Sprague-Dawley KW - Small-Conductance Calcium-Activated Potassium Channels KW - Vasodilation ER - TY - JOUR TI - Corneal endothelial cell density in glaucoma AU - Gagnon, M. M. AU - Boisjoly, H. M. AU - Brunette, I. AU - Charest, M. AU - Amyot, M. T2 - Cornea AB - PURPOSE: We studied corneal endothelial cell density in patients with glaucoma. METHODS: One hundred two patients with glaucoma were compared with 52 patients without glaucoma of the same age group. Exclusion criteria included history of either corneal disease, ocular inflammation, trauma, or surgery other than peripheral iridectomy. The following data were extracted from the patient files: glaucoma type and duration, laser treatments, glaucoma medications, and documented intraocular pressure (IOP) measurements. Specular microscopies were performed on central corneas, endothelial images were analyzed by computerized planimetry, and cell counts were calculated. RESULTS: Corneal endothelial cell counts were significantly lower in patients with glaucoma (2,154 +/- 419 cells/mm2) than in controls (2,560 +/- 360 cells/mm2; t test, p < 0.0001). In the glaucoma group, cell counts were inversely proportional to the means of IOPs. Patients receiving three or four glaucoma medications had lower cell counts than those receiving one or two medications. Cell counts were significantly lower both in primary angle-closure glaucoma and in primary open-angle glaucoma. CONCLUSION: This study suggests that patients with glaucoma may have lower corneal endothelial cell density than those without glaucoma of the same age group. The proposed mechanisms are direct damage from IOP, congenital alteration of the corneal endothelium in patients with glaucoma, glaucoma medication toxicity, or a combination of these. DA - 1997/05// PY - 1997 DP - PubMed VL - 16 IS - 3 SP - 314 EP - 318 J2 - Cornea LA - eng SN - 0277-3740 L2 - http://www.ncbi.nlm.nih.gov/pubmed/9143804 KW - Aged KW - Cell Count KW - Endothelium, Corneal KW - Female KW - Glaucoma, Angle-Closure KW - Glaucoma, Open-Angle KW - Humans KW - Image Processing, Computer-Assisted KW - Intraocular Pressure KW - Male KW - Ocular Hypertension KW - Video Recording ER - TY - JOUR TI - Data quality aware analysis of differential expression in RNA-seq with NOISeq R/Bioc package AU - Tarazona, Sonia AU - Furió-Tarí, Pedro AU - Turrà, David AU - Pietro, Antonio Di AU - Nueda, María José AU - Ferrer, Alberto AU - Conesa, Ana T2 - Nucleic Acids Research AB - As the use of RNA-seq has popularized, there is an increasing consciousness of the importance of experimental design, bias removal, accurate quantification and control of false positives for proper data analysis. We introduce the NOISeq R-package for quality control and analysis of count data. We show how the available diagnostic tools can be used to monitor quality issues, make pre-processing decisions and improve analysis. We demonstrate that the non-parametric NOISeqBIO efficiently controls false discoveries in experiments with biological replication and outperforms state-of-the-art methods. NOISeq is a comprehensive resource that meets current needs for robust data-aware analysis of RNA-seq differential expression. DA - 2015/12/02/ PY - 2015 DO - 10.1093/nar/gkv711 DP - Silverchair VL - 43 IS - 21 SP - e140 EP - e140 J2 - Nucleic Acids Research SN - 0305-1048 UR - https://doi.org/10.1093/nar/gkv711 Y2 - 2021/04/24/22:38:09 L1 - https://academic.oup.com/nar/article-pdf/43/21/e140/17435004/gkv711.pdf L2 - https://academic.oup.com/nar/article/43/21/e140/2468096 ER - TY - ELEC TI - DAVID Functional Annotation Bioinformatics Microarray Analysis UR - https://david.ncifcrf.gov/ Y2 - 2021/04/24/23:07:31 L2 - https://david.ncifcrf.gov/ ER - TY - JOUR TI - Decreased expression of small-conductance Ca2+-activated K+ channels SK1 and SK2 in human chronic atrial fibrillation AU - Yu, Tao AU - Deng, Chunyu AU - Wu, Ruobin AU - Guo, Huiming AU - Zheng, Shaoyi AU - Yu, Xiyong AU - Shan, Zhixin AU - Kuang, Sujuan AU - Lin, Qiuxiong T2 - Life Sciences AB - Aims Small-conductance Ca2+-activated K+ (SK) channels are recognized as new ion channel candidates in atrial fibrillation (AF), with pivotal implications as novel drug targets due to their atrial-selective distribution in humans. The purpose of this study was to investigate whether SK channels and the Ca2+-activated K+ current (IK,Ca) are involved in electrical remodeling of human chronic AF (cAF) and whether they display the differential distribution between the right (RA) and left atria (LA). Main methods The right (RAA) and left atrial appendage (LAA) myocytes were obtained from 29 sinus rhythm (SR) and 22 cAF patients. The IK,Ca and action potential (AP) were recorded using the patch-clamp technique. Three SK channel subtypes (SK1–3) expressions were assayed by western blot and real-time quantitative PCR analysis. Key findings The IK,Ca was decreased and its role in AP repolarization was attenuated in cAF, concomitant with a significant decrease in protein and mRNA levels of SK1 and SK2. In either SR or cAF, there was no difference in the IK,Ca density and protein and mRNA expression levels of SK1–3 between RAA and LAA myocytes. Significance Our results demonstrated that SK1 and SK2 are involved in electrical remodeling of cAF. SK1–3 and IK,Ca do not display the inter-atrial differential distribution in SR or cAF. These findings provide a new insight into mechanisms of electrical remodeling of human cAF. DA - 2012/01/30/ PY - 2012 DO - 10.1016/j.lfs.2011.11.008 DP - ScienceDirect VL - 90 IS - 5 SP - 219 EP - 227 J2 - Life Sciences LA - en SN - 0024-3205 UR - https://www.sciencedirect.com/science/article/pii/S0024320511005704 Y2 - 2021/04/25/00:22:49 L1 - https://pdf.sciencedirectassets.com/271221/1-s2.0-S0024320512X0002X/1-s2.0-S0024320511005704/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEJD%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJGMEQCIHV81QM%2BmUiVZLN8xqrmh7L2CBh9lRcSvPThK25FdC4UAiBAZnOBF%2FOP8G1XGNerM1nyxoZzdmQyXVStVNZUINos5Cq9Awj5%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F8BEAMaDDA1OTAwMzU0Njg2NSIMhaCl8HDoqCv5r85oKpEDLbD5f0f03Ohj2e6jBKGzuiKzrtYT4V3Fg60Uu12z0kFH94iGkurWZvdbFRlo0YrtfaRYVGD3Eh97SRFs4zlkgIbH6tUINYVN6Z%2BBlozESJcDZUpxypukuZcWLrKoEV6H73CYxOL6zGrx3jxYS4btIdOyWJR8IUm5VgEB67E77LNxiJSuqwtHz%2BoTVsQaqyc2386LTJpxF1ekykWOZNiE7Q5Z0D0NiMkupR4mKj7lz%2BuK88sker5eU3McqdT58YUbtCnAqCC6x3aOnSoiD%2Fgsmm5imvUpMV3gtXlibqOml8Dvx9ClG0bRF9Trymf5%2Bwhco1rlGsimGoNOwa8pRARQCUxuzqT6twwXUi0pm%2F8dGV3Ob%2FRpVl7FimUwUhKsJ31D%2B0Cx8Dy0DhI5aW93r0OaNsG2qtbbsBVzGx1ppPWdg3UY5rGyb9QtFw3pXfCKv74oAZSyns9UPzYPHVo2OUCt4Xvh6CQFPo5ugH5m2Dp0ZAli6myfZukxlKQl6CHWr6Th0XFqzFPfE6lcZoJsL1qd8r8w2t6ShAY67AEPApKAP6GNzojND3okDC%2FiRaSIZlAlg5vzfSXhfO1jx6gvDA785GI01Kszj2F35%2FNjl%2FzxXxVb5FD9jWFlXGd82BG%2FxFLhi7YzA8%2FFKWqn5GDnSBDCtc5iUx6IfW2fAe0DI4lTj4jFwb8sOQD%2BxwU6XqRy9y%2FOQtK%2BSyH7R9iCOb%2F5d5AVpeNOjAg5rTl1OXg10gbBfFwzY8l7KT4uoxisyiiaTgJeoaaSwczjwSEv6ob0xszFZ6GCAuAt1NVOpCmIIiCK5zoZX%2FZCC5EgCw%2BBNNzBHPXcXJus7qb%2FS66toyIG16PAx8n1dgDsNw%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210425T002249Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYRECLP4FK%2F20210425%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=97480e2362b2e8c537b0efc77e6e0a7b26cc20b1577fc22f3aa6aecdaede23b6&hash=14eef685bb9ea9d6379dd7e94a16ff50a0ef20ceee6d64f1553ac03f40a58aed&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0024320511005704&tid=spdf-63df0957-518b-40c2-8f90-16d961099ba6&sid=6593531c3c18a54b48592a4119b445a123dagxrqa&type=client L2 - http://www.sciencedirect.com/science/article/pii/S0024320511005704?via%3Dihub KW - Arrhythmia KW - Atrial fibrillation KW - Ion channels KW - SK channels ER - TY - JOUR TI - KCa3.1 (IK) modulates pancreatic cancer cell migration, invasion and proliferation: anomalous effects on TRAM-34 AU - Bonito, B. AU - Sauter, D. R. P. AU - Schwab, A. AU - Djamgoz, M. B. A. AU - Novak, I. T2 - Pflügers Archiv - European Journal of Physiology AB - In the recent decades, ion channels became the focus of cancer biologists, as many channels are overexpressed in tumour tissue and functionally they are linked to abnormal cell behaviour with processes including apoptosis, chemo- and radioresistance, proliferation and migration. KCa3.1 is a Ca2+-activated K+ channel that plays a central role in tumour progression in many cancer types. Therefore, the aim of the present study was to investigate KCa3.1 expression in pancreatic cancer cells and assess possible implications to disease progression. Using qPCR technique, we found abundant expression of KCa3.1 in pancreatic cancer cell lines. Patch clamp measurements on MiaPaCa-2 cells revealed a Ca2+-activated K+ current that matched biophysical characteristics as described for KCa3.1. Moreover, the current was sensitive to the commonly used channel modulators TRAM-34, clotrimazole and DC-EBIO, and it was abolished following transient gene knockdown of KCa3.1. We utilized both pharmacology and RNAi to assess a possible role of the channel in tumour cell behaviour. We found that the channel supported MiaPaCa-2 cell proliferation. Using RNAi protocols, we also identified KCa3.1 as important entity in cell invasion. However, TRAM-34 had unexpected stimulatory effects on cell migration and invasion estimated in various assays. Moreover, TRAM-34 increased intracellular Ca2+. In conclusion, we found prominent functional expression of KCa3.1 in pancreatic cancer cells. We provide evidence that the channel has a key role in cell proliferation and for the first time identify KCa3.1 as important entity in PDAC cell migration. We further reveal anomalous effects of TRAM-34. DA - 2016/11/01/ PY - 2016 DO - 10.1007/s00424-016-1891-9 DP - Springer Link VL - 468 IS - 11 SP - 1865 EP - 1875 J2 - Pflugers Arch - Eur J Physiol LA - en SN - 1432-2013 ST - KCa3.1 (IK) modulates pancreatic cancer cell migration, invasion and proliferation UR - https://doi.org/10.1007/s00424-016-1891-9 Y2 - 2021/04/25/01:36:47 L1 - http://link.springer.com/content/pdf/10.1007%2Fs00424-016-1891-9.pdf ER - TY - JOUR TI - Optimized solubilization of TRIzol-precipitated protein permits Western blotting analysis to maximize data available from brain tissue AU - Kopec, Ashley M. AU - Rivera, Phillip D. AU - Lacagnina, Michael J. AU - Hanamsagar, Richa AU - Bilbo, Staci D. T2 - Journal of Neuroscience Methods AB - Background Techniques simultaneously assessing multiple levels of molecular processing are appealing because molecular signaling underlying complex neural phenomena occurs at complementary levels. The TRIzol method isolates RNA and DNA, but protein retrieval is difficult due to inefficient solubilization of precipitated protein pellets. New method We optimized a buffer for the efficient solubilization of protein from TRIzol-precipitated brain tissue for Western blotting analysis, which was also more effective at directly homogenizing brain tissue than RIPA buffer. Results Protein yield during solubilization, in addition to protein yield via direct homogenization, is increased by optimizing concentrations of chemicals in a standard lysis buffer. Effective incubation parameters for both total protein yield and the analysis of post-translational modifications is remarkably flexible. Importantly, different neural cell types and protein classes are represented in solubilized protein samples. Moreover, we used dissociated mouse brain tissue to isolate microglia from other cell types and successfully resolved cell type-specific proteins from these small and difficult to attain samples. Comparison with existing method(s) Solubilization buffers to date have been comprised primarily of SDS or urea; the data herein demonstrate that components common to lysis buffers can also enhance protein solubilization both after direct homogenization and after precipitation. Conclusions This method is suitable for assessing gene and protein expression from a single brain sample, allowing for a more comprehensive evaluation of neural phenomena while minimizing the number of subjects. DA - 2017/03/15/ PY - 2017 DO - 10.1016/j.jneumeth.2017.02.002 DP - ScienceDirect VL - 280 SP - 64 EP - 76 J2 - Journal of Neuroscience Methods LA - en SN - 0165-0270 UR - https://www.sciencedirect.com/science/article/pii/S0165027017300389 Y2 - 2021/04/25/02:12:42 L1 - https://pdf.sciencedirectassets.com/271055/1-s2.0-S0165027017X00034/1-s2.0-S0165027017300389/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEJL%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIQCynpO8dLhs6KHeANP09bBpULintvr%2BC6IkSxGNPSirTAIgY0ld1QrHcbJ8mOPWz%2FLSiq7JDEepRCuuzw%2BWjlpBtD8qvQMI%2Bv%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARADGgwwNTkwMDM1NDY4NjUiDAsYEDNxGNz4gyRBsSqRAwtGcUfeUgB4m%2BkwJH5Tp%2FKVdN9e6b1zkgHbgOOICFs220QwnynmX4QXzyT029by8DhWs6VQ3gWD42%2BzZghxq3oK%2F2Zlm%2Ff7gn3wK0gUlaV3EfHWsjUWy5jWey%2FJVsRBq0nqmnxTrf%2BAXvEKIjYyt9wtY%2BYZDE%2Fem8FdzXGVOc50j%2BiaiZqnz5BqADR1pJCDshX6gadrt41fYQLJk7XpTJDyHrzqykt7Pa%2Ba3bhI7snf%2FO6fLVsNhOc%2BagsE1m4pNuZ6tvy%2BhIEo6Q1jplVxUPwBnQgJ%2FJkqiP50tZjYg%2FcaU6kmcaeCGvVt6mIv2LXVnNTBm1NtWGT4fk%2BJl8Jr4sptRcGf22%2FPQACpbURD%2Br4%2FyC6DCgHhx%2FxSGZSner5lh%2BQ8vV3cegLinmWpXmM%2BHcgfqu4YwZeHZpDo6xPvEW3NKQI8LFvfwKLfends00VhzObAT5Fe1TmKVEgxODQDEsZDUVrYnmfqNCT%2BbS5qo7hZMoo0p6CtedMUnPCcx5T7HwOGF%2Bzwy52EIAX0stuWrz0XMMuBk4QGOusBFM6fHjWRN73Yhpm%2BmQcGarpnp78MrkPb1YlsPxYhbuWtp97EtSf5gnpW1RSm7Wef3T0WripUVC7Sq%2FuMWtMLeGMy0jGmd0DRPf6IOefFv8XhpDud4EVXvMkgGwlEmnXI1U2wbUT%2BzT7S7UdwLwKpMyUua8D8w4opU9U6vs8%2F3cQ05qRAa%2FvmjzQATTG%2Fx27WC0gH2TrXSwTp%2FlrP%2FEmNUR8c1P1VWrNqNjnWduFW3iU0Bv8I5tQUsW75TlYf7sOM84UW5jehqOrFVgGdu4XQioNREjwesDVojTBmQr%2FLKItL37cw%2Fpcbmk%2BJ8g%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210425T021241Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY2COZWL5R%2F20210425%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=4209c545adc405ad10a2528f56530bea9c2406ba8d074521da71104b5ecf51f8&hash=a4433735bd076cd111290b4902ac5bdf74af680e8101c668aee41d7edd9b15c7&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0165027017300389&tid=spdf-c0425f7a-cdb0-495e-8a33-2a0e079eeffb&sid=4ea0e8642fd9d247264b594-6f7cb46eb4ebgxrqa&type=client L2 - http://www.sciencedirect.com/science/article/pii/S0165027017300389?via%3Dihub KW - Protein precipitation KW - Protein solubilization KW - RIPA buffer KW - TRIzol KW - Western blotting ER - TY - ELEC TI - Ion Transport Function of SLC4A11 in Corneal Endothelium | IOVS | ARVO Journals UR - https://iovs.arvojournals.org/article.aspx?articleid=2189793 Y2 - 2021/05/09/22:00:06 L2 - https://iovs.arvojournals.org/article.aspx?articleid=2189793 ER - TY - JOUR TI - Ion Transport Function of SLC4A11 in Corneal Endothelium AU - Jalimarada, Supriya S. AU - Ogando, Diego G. AU - Vithana, Eranga N. AU - Bonanno, Joseph A. T2 - Investigative Ophthalmology & Visual Science DA - 2013/06/01/ PY - 2013 DO - 10.1167/iovs.13-11929 DP - iovs.arvojournals.org VL - 54 IS - 6 SP - 4330 EP - 4340 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - https://iovs.arvojournals.org/article.aspx?articleid=2189793 Y2 - 2021/05/09/22:00:32 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/933468/i1552-5783-54-6-4330.pdf ER - TY - JOUR TI - Molecular and cellular basis of small--and intermediate-conductance, calcium-activated potassium channel function in the brain AU - Pedarzani, P. AU - Stocker, M. T2 - Cellular and molecular life sciences: CMLS AB - Small conductance calcium-activated potassium (SK or K(Ca)2) channels link intracellular calcium transients to membrane potential changes. SK channel subtypes present different pharmacology and distribution in the nervous system. The selective blocker apamin, SK enhancers and mice lacking specific SK channel subunits have revealed multifaceted functions of these channels in neurons, glia and cerebral blood vessels. SK channels regulate neuronal firing by contributing to the afterhyperpolarization following action potentials and mediating I(AHP), and partake in a calcium-mediated feedback loop with NMDA receptors, controlling the threshold for induction of hippocampal long-term potentiation. The function of distinct SK channel subtypes in different neurons often results from their specific coupling to different calcium sources. The prominent role of SK channels in the modulation of excitability and synaptic function of limbic, dopaminergic and cerebellar neurons hints at their possible involvement in neuronal dysfunction, either as part of the causal mechanism or as potential therapeutic targets. DA - 2008/10// PY - 2008 DO - 10.1007/s00018-008-8216-x DP - PubMed VL - 65 IS - 20 SP - 3196 EP - 3217 J2 - Cell Mol Life Sci LA - eng SN - 1420-682X L1 - https://link.springer.com/content/pdf/10.1007%2Fs00018-008-8216-x.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/18597044 KW - Amino Acid Sequence KW - Animals KW - Brain KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Mental Disorders KW - Molecular Sequence Data KW - Neurons KW - Small-Conductance Calcium-Activated Potassium Channels ER - TY - ELEC TI - SK2 and SK3 Expression Differentially Affect Firing Frequency and Precision in Dopamine Neurons UR - https://www-ncbi-nlm-nih-gov.ez.urosario.edu.co/pmc/articles/PMC3383402/ Y2 - 2021/05/09/22:12:02 L2 - https://www-ncbi-nlm-nih-gov.ez.urosario.edu.co/pmc/articles/PMC3383402/ ER - TY - JOUR TI - SK2 and SK3 Expression Differentially Affect Firing Frequency and Precision in Dopamine Neurons AU - Deignan, Jason AU - Luján, Rafael AU - Bond, Chris AU - Riegel, Arthur AU - Watanabe, Masahiko AU - Williams, John T. AU - Maylie, James AU - Adelman, John P. T2 - Neuroscience AB - The firing properties of dopamine (DA) neurons in the substantia nigra (SN) pars compacta are strongly influenced by the activity of apamin-sensitive small conductance Ca2+-activated K+ (SK) channels. Of the three SK channel genes expressed in central neurons, only SK3 expression has been identified in DA neurons. The present findings show that SK2 was also expressed in DA neurons. Immuno-electron microscopy (iEM) showed that SK2 was primarily expressed in the distal dendrites, while SK3 was heavily expressed in the soma and, to a lesser extent, throughout the dendritic arbor. Electrophysiological recordings of the effects of the SK channel blocker apamin on DA neurons from wild type and SK−/− mice show that SK2-containing channels contributed to the precision of action potential (AP) timing, while SK3-containing channels influenced AP frequency. The expression of SK2 in DA neurons may endow distinct signaling and subcellular localization to SK2-containing channels. Keywords: Substantia Nigra, Dopamine, SK channels, spontaneous activity, pacemaker DA - 2012/08/16/ PY - 2012 DO - 10.1016/j.neuroscience.2012.04.053 DP - PubMed Central VL - 217 SP - 67 EP - 76 J2 - Neuroscience SN - 0306-4522 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3383402/ Y2 - 2021/05/09/22:12:04 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3383402/pdf/nihms373855.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3383402/ ER - TY - JOUR TI - Small-conductance Ca 2+ -activated K + channels: insights into their roles in cardiovascular disease AU - Gu, Mingxia AU - Zhu, Yanrong AU - Yin, Xiaorong AU - Zhang, Dai-Min T2 - Experimental & Molecular Medicine AB - Life-threatening malignant arrhythmias in pathophysiological conditions can increase the mortality and morbidity of patients with cardiovascular diseases. Cardiac electrical activity depends on the coordinated propagation of excitatory stimuli and the generation of action potentials in cardiomyocytes. Action potential formation results from the opening and closing of ion channels. Recent studies have indicated that small-conductance calcium-activated potassium (SK) channels play a critical role in cardiac repolarization in pathophysiological but not normal physiological conditions. The aim of this review is to describe the role of SK channels in healthy and diseased hearts, to suggest cardiovascular pathophysiologic targets for intervention, and to discuss studies of agents that target SK channels for the treatment of cardiovascular diseases. DA - 2018/04// PY - 2018 DO - 10.1038/s12276-018-0043-z DP - www.nature.com VL - 50 IS - 4 SP - 1 EP - 7 LA - en SN - 2092-6413 ST - Small-conductance Ca 2+ -activated K + channels UR - https://www.nature.com/articles/s12276-018-0043-z Y2 - 2021/05/09/22:24:50 L1 - https://www.nature.com/articles/s12276-018-0043-z.pdf L2 - https://www.nature.com/articles/s12276-018-0043-z ER - TY - JOUR TI - α-Actinin2 cytoskeletal protein is required for the functional membrane localization of a Ca2+-activated K+ channel (SK2 channel) AU - Lu, Ling AU - Timofeyev, Valeriy AU - Li, Ning AU - Rafizadeh, Sassan AU - Singapuri, Anil AU - Harris, Todd R. AU - Chiamvimonvat, Nipavan T2 - Proceedings of the National Academy of Sciences of the United States of America AB - The importance of proper ion channel trafficking is underpinned by a number of channel-linked genetic diseases whose defect is associated with failure to reach the cell surface. Conceptually, it is reasonable to suggest that the function of ion channels depends critically on the precise subcellular localization and the number of channel proteins on the cell surface membrane, which is determined jointly by the secretory and endocytic pathways. Yet the precise mechanisms of the entire ion channel trafficking pathway remain unknown. Here, we directly demonstrate that proper membrane localization of a small-conductance Ca2+-activated K+ channel (SK2 or KCa2.2) is dependent on its interacting protein, α-actinin2, a major F-actin crosslinking protein. SK2 channel localization on the cell-surface membrane is dynamically regulated, and one of the critical steps includes the process of cytoskeletal anchoring of SK2 channel by its interacting protein, α-actinin2, as well as endocytic recycling via early endosome back to the cell membrane. Consequently, alteration of these components of SK2 channel recycling results in profound changes in channel surface expression. The importance of our findings may transcend the area of K+ channels, given that similar cytoskeletal interaction and anchoring may be critical for the membrane localization of other ion channels in neurons and other excitable cells. DA - 2009/10/27/ PY - 2009 DO - 10.1073/pnas.0908207106 DP - PubMed Central VL - 106 IS - 43 SP - 18402 EP - 18407 J2 - Proc Natl Acad Sci U S A SN - 0027-8424 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775294/ Y2 - 2021/05/09/22:46:35 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775294/pdf/zpq18402.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775294/ ER - TY - JOUR TI - SK channel enhancers attenuate Ca2+-dependent arrhythmia in hypertrophic hearts by regulating mito-ROS-dependent oxidation and activity of RyR AU - Kim, Tae Yun AU - Terentyeva, Radmila AU - Roder, Karim H. F. AU - Li, Weiyan AU - Liu, Man AU - Greener, Ian AU - Hamilton, Shanna AU - Polina, Iuliia AU - Murphy, Kevin R. AU - Clements, Richard T. AU - Dudley, Samuel C. AU - Koren, Gideon AU - Choi, Bum-Rak AU - Terentyev, Dmitry T2 - Cardiovascular Research AB - Aims Plasmamembrane small conductance Ca2+-activated K+ (SK) channels were implicated in ventricular arrhythmias in infarcted and failing hearts. Recently, SK channels were detected in the inner mitochondria membrane (IMM) (mSK), and their activation protected from acute ischaemia-reperfusion injury by reducing intracellular levels of reactive oxygen species (ROS). We hypothesized that mSK play an important role in regulating mitochondrial function in chronic cardiac diseases. We investigated the role of mSK channels in Ca2+-dependent ventricular arrhythmia using rat model of cardiac hypertrophy induced by banding of the ascending aorta thoracic aortic banding (TAB). Methods and results Dual Ca2+ and membrane potential optical mapping of whole hearts derived from TAB rats revealed that membrane-permeable SK enhancer NS309 (2 μM) improved aberrant Ca2+ homeostasis and abolished VT/VF induced by β-adrenergic stimulation. Using whole cell patch-clamp and confocal Ca2+ imaging of cardiomyocytes derived from TAB hearts (TCMs) we found that membrane-permeable SK enhancers NS309 and CyPPA (10 μM) attenuated frequency of spontaneous Ca2+ waves and delayed afterdepolarizations. Furthermore, mSK inhibition enhanced (UCL-1684, 1 μM); while activation reduced mitochondrial ROS production in TCMs measured with MitoSOX. Protein oxidation assays demonstrated that increased oxidation of ryanodine receptors (RyRs) in TCMs was reversed by SK enhancers. Experiments in permeabilized TCMs showed that SK enhancers restored SR Ca2+ content, suggestive of substantial improvement in RyR function. Conclusion These data suggest that enhancement of mSK channels in hypertrophic rat hearts protects from Ca2+-dependent arrhythmia and suggest that the protection is mediated via decreased mitochondrial ROS and subsequent decreased oxidation of reactive cysteines in RyR, which ultimately leads to stabilization of RyR-mediated Ca2+ release. DA - 2017/03// PY - 2017 DO - 10.1093/cvr/cvx005 DP - PubMed Central VL - 113 IS - 3 SP - 343 EP - 353 J2 - Cardiovasc Res SN - 0008-6363 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5852621/ Y2 - 2021/05/09/22:48:47 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5852621/pdf/cvx005.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5852621/ ER - TY - JOUR TI - Laminar shear stress upregulates endothelial Ca2+-activated K+ channels KCa2.3 and KCa3.1 via a Ca2+/calmodulin-dependent protein kinase kinase/Akt/p300 cascade AU - Takai, Jun AU - Santu, Alexandra AU - Zheng, Haifeng AU - Koh, Sang Don AU - Ohta, Masanori AU - Filimban, Linda M. AU - Lemaître, Vincent AU - Teraoka, Ryutaro AU - Jo, Hanjoong AU - Miura, Hiroto T2 - American Journal of Physiology-Heart and Circulatory Physiology AB - In endothelial cells (ECs), Ca2+-activated K+ channels KCa2.3 and KCa3.1 play a crucial role in the regulation of arterial tone via producing NO and endothelium-derived hyperpolarizing factors. Since a rise in intracellular Ca2+ levels and activation of p300 histone acetyltransferase are early EC responses to laminar shear stress (LS) for the transcriptional activation of genes, we examined the role of Ca2+/calmodulin-dependent kinase kinase (CaMKK), the most upstream element of a Ca2+/calmodulin-kinase cascade, and p300 in LS-dependent regulation of KCa2.3 and KCa3.1 in ECs. Exposure to LS (15 dyn/cm2) for 24 h markedly increased KCa2.3 and KCa3.1 mRNA expression in cultured human coronary artery ECs (3.2 ± 0.4 and 45 ± 10 fold increase, respectively; P < 0.05 vs. static condition; n = 8–30), whereas oscillatory shear (OS; ± 5 dyn/cm2 × 1 Hz) moderately increased KCa3.1 but did not affect KCa2.3. Expression of KCa2.1 and KCa2.2 was suppressed under both LS and OS conditions, whereas KCa1.1 was slightly elevated in LS and unchanged in OS. Inhibition of CaMKK attenuated LS-induced increases in the expression and channel activity of KCa2.3 and KCa3.1, and in phosphorylation of Akt (Ser473) and p300 (Ser1834). Inhibition of Akt abolished the upregulation of these channels by diminishing p300 phosphorylation. Consistently, disruption of the interaction of p300 with transcription factors eliminated the induction of these channels. Thus a CaMKK/Akt/p300 cascade plays an important role in LS-dependent induction of KCa2.3 and KCa3.1 expression, thereby regulating EC function and adaptation to hemodynamic changes. DA - 2013/06/21/ PY - 2013 DO - 10.1152/ajpheart.00642.2012 DP - journals.physiology.org (Atypon) VL - 305 IS - 4 SP - H484 EP - H493 SN - 0363-6135 UR - https://journals.physiology.org/doi/full/10.1152/ajpheart.00642.2012 Y2 - 2021/05/09/23:17:04 L1 - https://journals.physiology.org/doi/pdf/10.1152/ajpheart.00642.2012 L2 - https://journals.physiology.org/doi/full/10.1152/ajpheart.00642.2012 ER - TY - ELEC TI - Ca2+‐activated K+ channels in human melanoma cells are up‐regulated by hypoxia involving hypoxia‐inducible factor‐1α and the von Hippel‐Lindau protein - Tajima - 2006 - The Journal of Physiology - Wiley Online Library UR - https://physoc.onlinelibrary.wiley.com/doi/full/10.1113/jphysiol.2005.096818 Y2 - 2021/05/09/23:19:41 L2 - https://physoc.onlinelibrary.wiley.com/doi/full/10.1113/jphysiol.2005.096818 ER - TY - JOUR TI - Ion Channel Expression in Human Melanoma Samples: In Silico Identification and Experimental Validation of Molecular Targets AU - D’Arcangelo, Daniela AU - Scatozza, Francesca AU - Giampietri, Claudia AU - Marchetti, Paolo AU - Facchiano, Francesco AU - Facchiano, Antonio T2 - Cancers AB - Expression of 328 ion channel genes was investigated, by in silico analysis, in 170 human melanoma samples and controls. Ninety-one members of this gene-family (i.e., about 28%) show a significant (p < 0.05) differential expression in melanoma- vs. nevi-biopsies, taken from the GEO database. ROC (receiver operating characteristic) analysis selected 20 genes as potential markers showing the highest discrimination ability of melanoma vs. nevi (AUC > 0.90 and p < 0.0001). These 20 genes underwent a first in silico-validation round in an independent patients-dataset from GEO. A second-in silico-validation step was then carried out on a third human dataset in Oncomine. Finally, five genes were validated, showing extremely high sensitivity and specificity in melanoma detection (>90% in most cases). Such five genes (namely, SCNN1A, GJB3, KCNK7, GJB1, KCNN2) are novel potential melanoma markers or molecular targets, never previously related to melanoma. The “druggable genome” analysis was then carried out. Miconazole, an antifungal drug commonly used in clinics, is known to target KCNN2, the best candidate among the five identified genes. Miconazole was then tested in vitro in proliferation assays; it dose-dependently inhibited proliferation up to 90% and potently induced cell-death in A-375 and SKMEL-28 melanoma cells, while it showed no effect in control cells. Moreover, specific silencing of KCNN2 ion channel was achieved by siRNA transfection; under such condition miconazole strongly increases its anti-proliferative effect. In conclusion, the present study identified five ion channels that can potentially serve as sensitive and specific markers in human melanoma specimens and demonstrates that the antifungal drug miconazole, known to target one of the five identified ion channels, exerts strong and specific anti-melanoma effects in vitro. DA - 2019/04// PY - 2019 DO - 10.3390/cancers11040446 DP - www.mdpi.com VL - 11 IS - 4 SP - 446 LA - en ST - Ion Channel Expression in Human Melanoma Samples UR - https://www.mdpi.com/2072-6694/11/4/446 Y2 - 2021/05/09/23:21:47 L1 - https://www.mdpi.com/2072-6694/11/4/446/pdf L2 - https://www.mdpi.com/2072-6694/11/4/446 KW - KCNN2 KW - ion channels KW - melanoma KW - miconazole ER - TY - JOUR TI - Calcium-dependent regulation of secretion in biliary epithelial cells: the role of apamin-sensitive SK channels AU - Feranchak, Andrew P. AU - Doctor, R. Brian AU - Troetsch, Marlyn AU - Brookman, Kathryn AU - Johnson, Sylene M. AU - Fitz, J. Gregory T2 - Gastroenterology AB - BACKGROUND & AIMS: Increases in intracellular Ca 2+ are thought to complement cAMP in stimulating Cl - secretion in cholangiocytes, although the site(s) of action and channels involved are unknown. We have identified a Ca 2+ -activated K + channel (SK2) in biliary epithelium that is inhibited by apamin. The purpose of the present studies was to define the role of SK channels in Ca 2+ -dependent cholangiocyte secretion. METHODS: Studies were performed in human Mz-Cha-1 cells and normal rat cholangiocytes (NRC). Currents were measured by whole-cell patch clamp technique and transepithelial secretion by Ussing chamber. RESULTS: Ca 2+ -dependent stimuli, including purinergic receptor stimulation, ionomycin, and increases in cell volume, each activated K + -selective currents with a linear IV relation and time-dependent inactivation. Currents were Ca 2+ dependent and were inhibited by apamin and by Ba 2+. In intact liver, immunoflourescence with an antibody to SK2 showed a prominent signal in cholangiocyte plasma membrane. To evaluate the functional significance, NRC monolayers were mounted in a Ussing chamber, and the short-circuit current ( I sc ) was measured. Exposure to ionomycin caused an increase in I sc 2-fold greater than that induced by cAMP. Both the basal and ionomycin-induced I sc were inhibited by basolateral Ba 2+, and approximately 58% of the basolateral K + current was apamin sensitive. CONCLUSIONS: These studies demonstrate that cholangiocytes exhibit robust Ca 2+ -stimulated secretion significantly greater in magnitude than that stimulated by cAMP. SK2 plays an important role in mediating the increase in transepithelial secretion due to increases in intracellular Ca 2+. SK2 channels, therefore, may represent a target for pharmacologic modulation of bile flow. DA - 2004/09// PY - 2004 DO - 10.1053/j.gastro.2004.06.047 DP - PubMed VL - 127 IS - 3 SP - 903 EP - 913 J2 - Gastroenterology LA - eng SN - 0016-5085 ST - Calcium-dependent regulation of secretion in biliary epithelial cells L2 - http://www.ncbi.nlm.nih.gov/pubmed/15362045 KW - Animals KW - Apamin KW - Bee Venoms KW - Bile Ducts, Intrahepatic KW - Biological Transport KW - Calcium KW - Cell Line, Tumor KW - Cells, Cultured KW - Epithelial Cells KW - Humans KW - Ionomycin KW - Ionophores KW - Potassium KW - Potassium Channels KW - Potassium Channels, Calcium-Activated KW - Rats KW - Small-Conductance Calcium-Activated Potassium Channels ER - TY - JOUR TI - KCa2.3 channel-dependent hyperpolarization increases melanoma cell motility AU - Chantome, Aurelie AU - Girault, Alban AU - Potier, Marie AU - Collin, Christine AU - Vaudin, Pascal AU - Pagès, Jean-Christophe AU - Vandier, Christophe AU - Joulin, Virginie T2 - Experimental Cell Research AB - Cell migration and invasion are required for tumour cells to spread from the primary tumour bed so as to form secondary tumours at distant sites. We report evidence of an unusual expression of KCa2.3 (SK3) protein in melanoma cell lines but not in normal melanocytes. Knockdown of the KCa2.3 channel led to plasma membrane depolarization, decreased 2D and 3D cell motility. Conversely, enforced production of KCa2.3 protein in KCa2.3 non-expressing cells led to the plasma membrane becoming hyperpolarized, and enhanced cell motility. In contrast, KCa3.1 channels had no effect on cell motility despite an active role in regulating membrane potential. Our data also suggest that membrane hyperpolarization increases melanoma cell motility and that this occurs through the KCa2.3 channel. Our findings reveal a previously unknown function of the KCa2.3 channel, and suggest that the KCa2.3 channel might be the only member of the Ca(2+)-activated K(+) channel family involved in melanoma cell motility pathways. DA - 2009/12/10/ PY - 2009 DO - 10.1016/j.yexcr.2009.07.021 DP - PubMed VL - 315 IS - 20 SP - 3620 EP - 3630 J2 - Exp Cell Res LA - eng SN - 1090-2422 L2 - http://www.ncbi.nlm.nih.gov/pubmed/19646982 KW - Apamin KW - Cell Line, Tumor KW - Cell Movement KW - Cell Proliferation KW - Clotrimazole KW - Electrophysiological Phenomena KW - Gene Expression KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Melanocytes KW - Melanoma KW - Membrane Potentials KW - Patch-Clamp Techniques KW - Potassium Channel Blockers KW - Pyrazoles KW - RNA, Antisense KW - Small-Conductance Calcium-Activated Potassium Channels KW - Transfection ER - TY - JOUR TI - Formation of cellular projections in neural progenitor cells depends on SK3 channel activity AU - Liebau, Stefan AU - Vaida, Bianca AU - Proepper, Christian AU - Grissmer, Stephan AU - Storch, Alexander AU - Boeckers, Tobias M. AU - Dietl, Paul AU - Wittekindt, Oliver H. T2 - Journal of Neurochemistry AB - Ion channels are potent modulators for developmental processes in progenitor cells. In a screening approach for different ion channels in neural progenitor cells (NPCs) we observed a 1-ethyl-2-benzimidazolinone (1-EBIO) activated inward current, which could be blocked by scyllatoxin (ScTX, IC50 = 2 ± 0.3 nmol/L). This initial evidence for the expression of the small conductance Ca2+ activated K+-channel SK3 was confirmed by the detection of SK3 transcripts and protein in NPCs. Interestingly, SK3 proteins were highly expressed in non-differentiated NPCs with a focused localization in lamellipodia as well as filopodial structures. The activation of SK3 channels using 1-EBIO lead to an immediate filopodial sprouting and the translocation of the protein into these novel filopodial protrusions. Both effects could be prevented by the pre-incubation of NPCs with ScTX. Our study gives first evidence that the formation and prolongation of filopodia in NPCs is, at least in part, effectively induced and regulated by SK3 channels. DA - 2007/// PY - 2007 DO - https://doi.org/10.1111/j.1471-4159.2006.04437.x DP - Wiley Online Library VL - 101 IS - 5 SP - 1338 EP - 1350 LA - en SN - 1471-4159 UR - https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1471-4159.2006.04437.x Y2 - 2021/05/09/23:30:50 L1 - https://onlinelibrary.wiley.com/doi/pdfdirect/10.1111/j.1471-4159.2006.04437.x KW - calcium-activated potassium channels KW - filopodia KW - neural progenitor cells KW - SK3 channel ER - TY - JOUR TI - Altered SK3/KCa2.3-mediated migration in adenomatous polyposis coli (Apc) mutated mouse colon epithelial cells AU - Potier, Marie AU - Tran, Truong An AU - Chantome, Aurelie AU - Girault, Alban AU - Joulin, Virginie AU - Bougnoux, Philippe AU - Vandier, Christophe AU - Pierre, Fabrice T2 - Biochemical and Biophysical Research Communications AB - Lost of adenomatous polyposis coli gene (Apc) disturbs the migration of intestinal epithelial cells but the mechanisms have not been fully characterized. Since we have demonstrated that SK3/KCa2.3 channel promotes cancer cell migration, we hypothesized that Apc mutation may affect SK3/KCa2.3 channel-mediated colon epithelial cell motility. We report evidence that SK3/KCa2.3 channel promotes colon epithelial cells motility. Following Apc mutation SK3/KCa2.3 expression is largely reduced leading to a suppression of the SK3/KCa2.3 channel mediated-cell migration. Our findings reveal a previously unknown function of the SK3/KCa2.3 channel in epithelial colonic cells, and suggest that Apc is a powerful regulator SK3/KCa2.3 channel. DA - 2010/06/18/ PY - 2010 DO - 10.1016/j.bbrc.2010.05.046 DP - PubMed VL - 397 IS - 1 SP - 42 EP - 47 J2 - Biochem Biophys Res Commun LA - eng SN - 1090-2104 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20519134 KW - Adenomatous Polyposis Coli Protein KW - Animals KW - Cell Line KW - Cell Movement KW - Colon KW - Intestinal Mucosa KW - Mice KW - Mice, Mutant Strains KW - Small-Conductance Calcium-Activated Potassium Channels ER - TY - JOUR TI - Unexpected down-regulation of the hIK1 Ca2+-activated K+ channel by its opener 1-ethyl-2-benzimidazolinone in HaCaT keratinocytes. Inverse effects on cell growth and proliferation AU - Koegel, Heidi AU - Kaesler, Susanne AU - Burgstahler, Ralf AU - Werner, Sabine AU - Alzheimer, Christian T2 - The Journal of Biological Chemistry AB - We used a combination of electrophysiological and cell and molecular biological techniques to study the regulation and functional role of the intermediate conductance Ca(2+)-activated K(+) channel, hIK1, in HaCaT keratinocytes. When we incubated cells with the hIK1 opener, 1-ethyl-2-benzimidazolinone (1-EBIO), to investigate the cellular consequences of prolonged channel activity, an unexpected down-regulation of channels occurred within a few hours. The same effect was produced by the hIK1 openers chlorzoxazone and zoxazolamine and was also observed in a different cell line (C6 glioma cells). After 3 days of treatment with 1-EBIO, mRNA levels of hIK1 were substantially diminished and no channel activity was detected. Down-regulation of hIK1 was accompanied by a loss of mitogenic activity and a strong increase in cell size. After withdrawal of 1-EBIO, hIK1 mRNA and channel activity fully recovered and the cells resumed mitogenic activity. Our data present evidence for a novel feedback mechanism of hIK1 expression that appears to result from the paradoxical action of its pharmacological activator during prolonged application. Because the down-regulation of hIK1 bears immediate significance on the biological fate of keratinocytes, 1-EBIO and related compounds might emerge as potent tools to influence the proliferation of various non-excitable cells endowed with IK channels. DA - 2003/01/31/ PY - 2003 DO - 10.1074/jbc.M208914200 DP - PubMed VL - 278 IS - 5 SP - 3323 EP - 3330 J2 - J Biol Chem LA - eng SN - 0021-9258 L1 - https://www.jbc.org/content/278/5/3323.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/12421833 KW - Benzimidazoles KW - Calcium Channel Agonists KW - Cell Division KW - Cell Line KW - Gene Expression Regulation KW - Glioma KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Ion Channel Gating KW - Keratinocytes KW - Kinetics KW - Membrane Potentials KW - Potassium Channels KW - Potassium Channels, Calcium-Activated KW - RNA, Messenger KW - Tumor Cells, Cultured ER - TY - JOUR TI - The Ca2+-activated K+ channel KCNN4/KCa3.1 contributes to microglia activation and nitric oxide-dependent neurodegeneration AU - Kaushal, Vikas AU - Koeberle, Paulo D. AU - Wang, Yimin AU - Schlichter, Lyanne C. T2 - The Journal of Neuroscience: The Official Journal of the Society for Neuroscience AB - Brain damage and disease involve activation of microglia and production of potentially neurotoxic molecules, but there are no treatments that effectively target their harmful properties. We present evidence that the small-conductance Ca2+/calmodulin-activated K+ channel KCNN4/ KCa3.1/SK4/IK1 is highly expressed in rat microglia and is a potential therapeutic target for acute brain damage. Using a Transwell cell-culture system that allows separate treatment of the microglia or neurons, we show that activated microglia killed neurons, and this was markedly reduced by treating only the microglia with a selective inhibitor of KCa3.1 channels, triarylmethane-34 (TRAM-34). To assess the role of KCa3.1 channels in microglia activation and key signaling pathways involved, we exploited several fluorescence plate-reader-based assays. KCa3.1 channels contributed to microglia activation, inducible nitric oxide synthase upregulation, production of nitric oxide and peroxynitrite, and to consequent neurotoxicity, protein tyrosine nitration, and caspase 3 activation in the target neurons. Microglia activation involved the signaling pathways p38 mitogen-activated protein kinase (MAPK) and nuclear factor kappaB (NF-kappaB), which are important for upregulation of numerous proinflammatory molecules, and the KCa3.1 channels were functionally linked to activation of p38 MAPK but not NF-kappaB. These in vitro findings translated into in vivo neuroprotection, because we found that degeneration of retinal ganglion cells after optic nerve transection was reduced by intraocular injection of TRAM-34. This study provides evidence that KCa3.1 channels constitute a therapeutic target in the CNS and that inhibiting this K+ channel might benefit acute and chronic neurodegenerative disorders that are caused by or exacerbated by inflammation. DA - 2007/01/03/ PY - 2007 DO - 10.1523/JNEUROSCI.3593-06.2007 DP - PubMed VL - 27 IS - 1 SP - 234 EP - 244 J2 - J Neurosci LA - eng SN - 1529-2401 L1 - https://www.jneurosci.org/content/27/1/234.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/17202491 KW - Animals KW - Cells, Cultured KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Microglia KW - Neurodegenerative Diseases KW - Neurons KW - Nitric Oxide KW - Rats KW - Rats, Wistar ER - TY - JOUR TI - Apparent intermediate K conductance channel hyposmotic activation in human lens epithelial cells AU - Lauf, Peter K. AU - Misri, Sandeep AU - Chimote, Ameet A. AU - Adragna, Norma C. T2 - American Journal of Physiology-Cell Physiology AB - This study explores the nature of K fluxes in human lens epithelial cells (LECs) in hyposmotic solutions. Total ion fluxes, Na-K pump, Cl-dependent Na-K-2Cl (NKCC), K-Cl (KCC) cotransport, and K channels were determined by 85Rb uptake and cell K (Kc) by atomic absorption spectrophotometry, and cell water gravimetrically after exposure to ouabain ± bumetanide (Na-K pump and NKCC inhibitors), and ion channel inhibitors in varying osmolalities with Na, K, or methyl-d-glucamine and Cl, sulfamate, or nitrate. Reverse transcriptase polymerase chain reaction (RT-PCR), Western blot analyses, and immunochemistry were also performed. In isosmotic (300 mosM) media ∼90% of the total Rb influx occurred through the Na-K pump and NKCC and ∼10% through KCC and a residual leak. Hyposmotic media (150 mosM) decreased Kc by a 16-fold higher K permeability and cell water, but failed to inactivate NKCC and activate KCC. Sucrose replacement or extracellular K to >57 mM, but not Rb or Cs, in hyposmotic media prevented Kc and water loss. Rb influx equaled Kc loss, both blocked by clotrimazole (IC50 ∼25 μM) and partially by 1-[(2-chlorophenyl) diphenylmethyl]-1H-pyrazole (TRAM-34) inhibitors of the IK channel KCa3.1 but not by other K channel or connexin hemichannel blockers. Of several anion channel blockers (dihydro-indenyl)oxy]alkanoic acid (DIOA), 4-2(butyl-6,7-dichloro-2-cyclopentylindan-1-on-5-yl)oxybutyric acid (DCPIB), and phloretin totally or partially inhibited Kc loss and Rb influx, respectively. RT-PCR and immunochemistry confirmed the presence of KCa3.1 channels, aside of the KCC1, KCC2, KCC3 and KCC4 isoforms. Apparently, IK channels, possibly in parallel with volume-sensitive outwardly rectifying Cl channels, effect regulatory volume decrease in LECs. DA - 2008/03/01/ PY - 2008 DO - 10.1152/ajpcell.00375.2007 DP - journals-physiology-org.ez.urosario.edu.co (Atypon) VL - 294 IS - 3 SP - C820 EP - C832 J2 - American Journal of Physiology-Cell Physiology SN - 0363-6143 UR - http://journals.physiology.org/doi/full/10.1152/ajpcell.00375.2007 Y2 - 2021/05/09/23:45:14 L1 - http://journals.physiology.org/doi/pdf/10.1152/ajpcell.00375.2007 ER - TY - ELEC TI - Differential role of IK and BK potassium channels as mediators of intrinsic and extrinsic apoptotic cell death - PubMed UR - https://pubmed-ncbi-nlm-nih-gov.ez.urosario.edu.co/22992678/ Y2 - 2021/05/09/23:45:45 L2 - https://pubmed-ncbi-nlm-nih-gov.ez.urosario.edu.co/22992678/ ER - TY - ELEC TI - K ca 3.1 Activation Via P2y 2 Purinergic Receptors Promotes Human Ovarian Cancer Cell (Skov-3) Migration - PubMed UR - https://pubmed-ncbi-nlm-nih-gov.ez.urosario.edu.co/28659615/ Y2 - 2021/05/09/23:46:41 L2 - https://pubmed-ncbi-nlm-nih-gov.ez.urosario.edu.co/28659615/ ER - TY - JOUR TI - Kca3.1 Activation Via P2y2 Purinergic Receptors Promotes Human Ovarian Cancer Cell (Skov-3) Migration AU - Robles-Martínez, L. AU - Garay, E. AU - Martel-Gallegos, M. G. AU - Cisneros-Mejorado, A. AU - Pérez-Montiel, D. AU - Lara, A. AU - Arellano, R. O. T2 - Scientific Reports AB - Disorders in cell signaling mediated by ATP or histamine, activating specific membrane receptors, have been frequently associated with tumorigenesis. Among the elements of response to purinergic (and histaminergic) signaling, ion channel activation controls essential cellular processes in cancer, such as cell proliferation, motility, and death. Here, we studied the effects that ATP had on electrical properties of human ovarian adenocarcinoma cells named SKOV-3. ATP caused increase in intracellular Ca2+ concentration ([Ca2+]i) and, concurrently, it evoked a complex electrical response with a conspicuous outward component. This current was generated through P2Y2 receptor activation and opening of K+ channels, KCa3.1, as indicated by electrophysiological and pharmacological analysis, as well as by immunodetection and specific silencing of P2Y2 or KCa3.1 gene by esiRNA transfection. Low µM ATP concentration increased SKOV-3 cell migration, which was strongly inhibited by KCa3.1 channel blockers and by esiRNA-generated P2Y2 or KCa3.1 downregulation. Finally, in human ovarian tumors, the P2Y2 and KCa3.1 proteins are expressed and co-localized in neoplastic cells. Thus, stimulation of P2Y2 receptors expressed in SKOV-3 cells promotes motility through KCa3.1 activation. Since P2Y2 and KCa3.1 are co-expressed in primary tumors, our findings suggest that they may play a role in cancer progression. DA - 2017/06/28/ PY - 2017 DO - 10.1038/s41598-017-04292-6 DP - PubMed VL - 7 IS - 1 SP - 4340 J2 - Sci Rep LA - eng SN - 2045-2322 L1 - https://www.nature.com/articles/s41598-017-04292-6.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/28659615 KW - Adenosine Triphosphate KW - Calcium KW - Calcium Signaling KW - Cell Line, Tumor KW - Cell Movement KW - Cell Proliferation KW - Dose-Response Relationship, Drug KW - Female KW - Gene Expression KW - Gene Silencing KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Ion Channel Gating KW - Ions KW - Membrane Potentials KW - Ovarian Neoplasms KW - Potassium Channel Blockers KW - Receptors, Purinergic P2Y2 KW - RNA, Small Interfering ER - TY - JOUR TI - CXCL12-induced glioblastoma cell migration requires intermediate conductance Ca2+-activated K+ channel activity AU - Sciaccaluga, Miriam AU - Fioretti, Bernard AU - Catacuzzeno, Luigi AU - Pagani, Francesca AU - Bertollini, Cristina AU - Rosito, Maria AU - Catalano, Myriam AU - D'Alessandro, Giuseppina AU - Santoro, Antonio AU - Cantore, Giampaolo AU - Ragozzino, Davide AU - Castigli, Emilia AU - Franciolini, Fabio AU - Limatola, Cristina T2 - American Journal of Physiology-Cell Physiology AB - The activation of ion channels is crucial during cell movement, including glioblastoma cell invasion in the brain parenchyma. In this context, we describe for the first time the contribution of intermediate conductance Ca2+-activated K (IKCa) channel activity in the chemotactic response of human glioblastoma cell lines, primary cultures, and freshly dissociated tissues to CXC chemokine ligand 12 (CXCL12), a chemokine whose expression in glioblastoma has been correlated with its invasive capacity. We show that blockade of the IKCa channel with its specific inhibitor 1-[(2-chlorophenyl) diphenylmethyl]-1H-pyrazole (TRAM-34) or IKCa channel silencing by short hairpin RNA (shRNA) completely abolished CXCL12-induced cell migration. We further demonstrate that this is not a general mechanism in glioblastoma cell migration since epidermal growth factor (EGF), which also activates IKCa channels in the glioblastoma-derived cell line GL15, stimulate cell chemotaxis even if the IKCa channels have been blocked or silenced. Furthermore, we demonstrate that both CXCL12 and EGF induce Ca2+ mobilization and IKCa channel activation but only CXCL12 induces a long-term upregulation of the IKCa channel activity. Furthermore, the Ca2+-chelating agent BAPTA-AM abolished the CXCL12-induced, but not the EGF-induced, glioblastoma cell chemotaxis. In addition, we demonstrate that the extracellular signal-regulated kinase (ERK)1/2 pathway is only partially implicated in the modulation of CXCL12-induced glioblastoma cell movement, whereas the phosphoinositol-3 kinase (PI3K) pathway is not involved. In contrast, EGF-induced glioblastoma migration requires both ERK1/2 and PI3K activity. All together these findings suggest that the efficacy of glioblastoma invasiveness might be related to an array of nonoverlapping mechanisms activated by different chemotactic agents. DA - 2010/04/14/ PY - 2010 DO - 10.1152/ajpcell.00344.2009 DP - journals-physiology-org.ez.urosario.edu.co (Atypon) VL - 299 IS - 1 SP - C175 EP - C184 J2 - American Journal of Physiology-Cell Physiology SN - 0363-6143 UR - http://journals.physiology.org/doi/full/10.1152/ajpcell.00344.2009 Y2 - 2021/05/09/23:52:49 L1 - http://journals.physiology.org/doi/pdf/10.1152/ajpcell.00344.2009 L2 - http://journals.physiology.org/doi/full/10.1152/ajpcell.00344.2009 ER - TY - JOUR TI - Regulation of membrane potential and fluid secretion by Ca2+-activated K+ channels in mouse submandibular glands AU - Romanenko, Victor G AU - Nakamoto, Tetsuji AU - Srivastava, Alaka AU - Begenisich, Ted AU - Melvin, James E T2 - The Journal of Physiology AB - We have recently shown that the IK1 and maxi-K channels in parotid salivary gland acinar cells are encoded by the KCa3.1 and KCa1.1 genes, respectively, and in vivo stimulated parotid secretion is severely reduced in double-null mice. The current study tested whether submandibular acinar cell function also relies on these channels. We found that the K+ currents in submandibular acinar cells have the biophysical and pharmacological footprints of IK1 and maxi-K channels and their molecular identities were confirmed by the loss of these currents in KCa3.1- and KCa1.1-null mice. Unexpectedly, the pilocarpine-stimulated in vivo fluid secretion from submandibular glands was essentially normal in double-null mice. This result and the possibility of side-effects of pilocarpine on the nervous system, led us to develop an ex vivo fluid secretion assay. Fluid secretion from the ex vivo assay was substantially (about 75%) reduced in animals with both K+ channel genes ablated – strongly suggesting systemic complications with the in vivo assay. Additional experiments focusing on the membrane potential in isolated submandibular acinar cells revealed mechanistic details underlying fluid secretion in K+ channel-deficient mice. The membrane potential of submandibular acinar cells from wild-type mice remained strongly hyperpolarized (−55 ± 2 mV) relative to the Cl− equilibrium potential (−24 mV) during muscarinic stimulation. Similar hyperpolarizations were observed in KCa3.1- and KCa1.1-null mice (−51 ± 3 and −48 ± 3 mV, respectively), consistent with the normal fluid secretion produced ex vivo. In contrast, acinar cells from double KCa3.1/KCa1.1-null mice were only slightly hyperpolarized (−35 ± 2 mV) also consistent with the ex vivo (but not in vivo) results. Finally, we found that the modest hyperpolarization of cells from the double-null mice was maintained by the electrogenic Na+,K+-ATPase. DA - 2007/06/01/ PY - 2007 DO - 10.1113/jphysiol.2006.127498 DP - PubMed Central VL - 581 IS - Pt 2 SP - 801 EP - 817 J2 - J Physiol SN - 0022-3751 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2075181/ Y2 - 2021/05/09/23:53:45 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2075181/pdf/tjp0581-0801.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2075181/ ER - TY - JOUR TI - SK4 channels modulate Ca2+ signalling and cell cycle progression in murine breast cancer AU - Steudel, Friederike A. AU - Mohr, Corinna J. AU - Stegen, Benjamin AU - Nguyen, Hoang Y. AU - Barnert, Andrea AU - Steinle, Marc AU - Beer-Hammer, Sandra AU - Koch, Pierre AU - Lo, Wing-Yee AU - Schroth, Werner AU - Hoppe, Reiner AU - Brauch, Hiltrud AU - Ruth, Peter AU - Huber, Stephan M. AU - Lukowski, Robert T2 - Molecular Oncology AB - Oncogenic signalling via Ca2+ -activated K+ channels of intermediate conductance (SK4, also known as KCa 3.1 or IK) has been implicated in different cancer entities including breast cancer. Yet, the role of endogenous SK4 channels for tumorigenesis is unclear. Herein, we generated SK4-negative tumours by crossing SK4-deficient (SK4 KO) mice to the polyoma middle T-antigen (PyMT) and epidermal growth factor receptor 2 (cNeu) breast cancer models in which oncogene expression is driven by the retroviral promoter MMTV. Survival parameters and tumour progression were studied in cancer-prone SK4 KO in comparison with wild-type (WT) mice and in a syngeneic orthotopic mouse model following transplantation of SK4-negative or WT tumour cells. SK4 activity was modulated by genetic or pharmacological means using the SK4 inhibitor TRAM-34 in order to establish the role of breast tumour SK4 for cell growth, electrophysiological signalling, and [Ca2+ ]i oscillations. Ablation of SK4 and TRAM-34 treatment reduced the SK4-generated current fraction, growth factor-dependent Ca2+ entry, cell cycle progression and the proliferation rate of MMTV-PyMT tumour cells. In vivo, PyMT oncogene-driven tumorigenesis was only marginally affected by the global lack of SK4, whereas tumour progression was significantly delayed after orthotopic implantation of MMTV-PyMT SK4 KO breast tumour cells. However, overall survival and progression-free survival time in the MMTV-cNeu mouse model were significantly extended in the absence of SK4. Collectively, our data from murine breast cancer models indicate that SK4 activity is crucial for cell cycle control. Thus, the modulation of this channel should be further investigated towards a potential improvement of existing antitumour strategies in human breast cancer. DA - 2017/09// PY - 2017 DO - 10.1002/1878-0261.12087 DP - PubMed VL - 11 IS - 9 SP - 1172 EP - 1188 J2 - Mol Oncol LA - eng SN - 1878-0261 L1 - https://febs.onlinelibrary.wiley.com/doi/pdfdirect/10.1002/1878-0261.12087 L2 - http://www.ncbi.nlm.nih.gov/pubmed/28557306 KW - Animals KW - breast cancer KW - Ca2+-activated K+ channels of intermediate conductance (SK4, KCa3.1, IK, KCNN4) KW - Calcium KW - Calcium Signaling KW - Cell Cycle KW - Cell Line, Tumor KW - Cell Proliferation KW - Disease Models, Animal KW - epidermal growth factor receptor 2 (Her2/cNeu) KW - Female KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Intracellular Space KW - Kaplan-Meier Estimate KW - Male KW - Mammary Neoplasms, Experimental KW - Mammary Tumor Virus, Mouse KW - Mice KW - mouse mammary tumour virus (MMTV) KW - polyoma virus middle T-antigen (PyMT) KW - Time Factors ER - TY - JOUR TI - EGF and K+ channel activity control normal and cystic fibrosis bronchial epithelia repair AU - Trinh, Nguyen Thu Ngan AU - Privé, Anik AU - Maillé, Emilie AU - Noël, Josette AU - Brochiero, Emmanuelle T2 - American Journal of Physiology. Lung Cellular and Molecular Physiology AB - Severe lesions of airway epithelia are observed in cystic fibrosis (CF) patients. The regulatory mechanisms of cell migration and proliferation processes, involved in the repair of injured epithelia, then need to be better understood. A model of mechanical wounding of non-CF (NuLi) and CF (CuFi) bronchial monolayers was employed to study the repair mechanisms. We first observed that wound repair, under paracrine and autocrine EGF control, was slower (up to 33%) in CuFi than in NuLi. Furthermore, EGF receptor (EGFR) activation, following wounding, was lower in CuFi than in NuLi monolayers. Cell proliferation and migration assays indicated a similar rate of proliferation in both cell lines but with reduced (by 25%) CuFi cell migration. In addition, cell migration experiments performed in the presence of conditioned medium, collected from NuLi and CuFi wounded bronchial monolayers, suggested a defect in EGF/EGFR signaling in CF cells. We (49) recently demonstrated coupling between the EGF response and K(+) channel function, which is crucial for EGF-stimulated alveolar repair. In CuFi cells, lower EGF/EGFR signaling was accompanied by a 40-70% reduction in K(+) currents and KvLQT1, ATP-sensitive potassium (K(ATP)), and Ca(2+)-activated K(+) (KCa3.1) channel expression. In addition, EGF-stimulated bronchial wound healing, cell migration, and proliferation were severely decreased by K(+) channel inhibitors. Finally, acute CFTR inhibition failed to reduce wound healing, EGF secretion, and K(+) channel expression in NuLi. In summary, the delay in CuFi wound healing could be due to diminished EGFR signaling coupled with lower K(+) channel function, which play a crucial role in bronchial repair. DA - 2008/11// PY - 2008 DO - 10.1152/ajplung.90224.2008 DP - PubMed VL - 295 IS - 5 SP - L866 EP - 880 J2 - Am J Physiol Lung Cell Mol Physiol LA - eng SN - 1040-0605 L2 - http://www.ncbi.nlm.nih.gov/pubmed/18757521 KW - Bronchi KW - Cell Line KW - Cell Movement KW - Cell Proliferation KW - Cystic Fibrosis KW - Cystic Fibrosis Transmembrane Conductance Regulator KW - Epidermal Growth Factor KW - Epithelium KW - ErbB Receptors KW - Humans KW - Ion Channel Gating KW - Potassium Channels KW - Wound Healing ER - TY - JOUR TI - Calcium-dependent potassium channels control proliferation of cardiac progenitor cells and bone marrow-derived mesenchymal stem cells AU - Vigneault, Patrick AU - Naud, Patrice AU - Qi, Xiaoyan AU - Xiao, Jiening AU - Villeneuve, Louis AU - Davis, Darryl R. AU - Nattel, Stanley T2 - The Journal of Physiology AB - KEY POINTS: Ex vivo proliferated c-Kit+ endogenous cardiac progenitor cells (eCPCs) obtained from mouse and human cardiac tissues have been reported to express a wide range of functional ion channels. In contrast to previous reports in cultured c-Kit+ eCPCs, we found that ion currents were minimal in freshly isolated cells. However, inclusion of free Ca2+ intracellularly revealed a prominent inwardly rectifying current identified as the intermediate conductance Ca2+ -activated K+ current (KCa3.1) Electrical function of both c-Kit+ eCPCs and bone marrow-derived mesenchymal stem cells is critically governed by KCa3.1 calcium-dependent potassium channels. Ca2+ -induced increases in KCa3.1 conductance are necessary to optimize membrane potential during Ca2+ entry. Membrane hyperpolarization due to KCa3.1 activation maintains the driving force for Ca2+ entry that activates stem cell proliferation. Cardiac disease downregulates KCa3.1 channels in resident cardiac progenitor cells. Alterations in KCa3.1 may have pathophysiological and therapeutic significance in regenerative medicine. ABSTRACT: Endogenous c-Kit+ cardiac progenitor cells (eCPCs) and bone marrow (BM)-derived mesenchymal stem cells (MSCs) are being developed for cardiac regenerative therapy, but a better understanding of their physiology is needed. Here, we addressed the unknown functional role of ion channels in freshly isolated eCPCs and expanded BM-MSCs using patch-clamp, microfluorometry and confocal microscopy. Isolated c-Kit+ eCPCs were purified from dog hearts by immunomagnetic selection. Ion currents were barely detectable in freshly isolated c-Kit+ eCPCs with buffering of intracellular calcium (Ca2+i ). Under conditions allowing free intracellular Ca2+ , freshly isolated c-Kit+ eCPCs and ex vivo proliferated BM-MSCs showed prominent voltage-independent conductances that were sensitive to intermediate-conductance K+ -channel (KCa3.1 current, IKCa3.1 ) blockers and corresponding gene (KCNN4)-expression knockdown. Depletion of Ca2+i induced membrane-potential (Vmem ) depolarization, while store-operated Ca2+ entry (SOCE) hyperpolarized Vmem in both cell types. The hyperpolarizing SOCE effect was substantially reduced by IKCa3.1 or SOCE blockade (TRAM-34, 2-APB), and IKCa3.1 blockade (TRAM-34) or KCNN4-knockdown decreased the Ca2+ entry resulting from SOCE. IKCa3.1 suppression reduced c-Kit+ eCPC and BM-MSC proliferation, while significantly altering the profile of cyclin expression. IKCa3.1 was reduced in c-Kit+ eCPCs isolated from dogs with congestive heart failure (CHF), along with corresponding KCNN4 mRNA. Under perforated-patch conditions to maintain physiological [Ca2+ ]i , c-Kit+ eCPCs from CHF dogs had less negative resting membrane potentials (-58 ± 7 mV) versus c-Kit+ eCPCs from control dogs (-73 ± 3 mV, P < 0.05), along with slower proliferation. Our study suggests that Ca2+ -induced increases in IKCa3.1 are necessary to optimize membrane potential during the Ca2+ entry that activates progenitor cell proliferation, and that alterations in KCa3.1 may have pathophysiological and therapeutic significance in regenerative medicine. DA - 2018/06// PY - 2018 DO - 10.1113/JP275388 DP - PubMed VL - 596 IS - 12 SP - 2359 EP - 2379 J2 - J Physiol LA - eng SN - 1469-7793 L1 - https://physoc.onlinelibrary.wiley.com/doi/pdfdirect/10.1113/JP275388 L2 - http://www.ncbi.nlm.nih.gov/pubmed/29574723 KW - Animals KW - Calcium KW - Calcium Signalling KW - Cardiac progenitor cells KW - Cell Proliferation KW - Cells, Cultured KW - Dogs KW - Female KW - Heart Failure KW - Heart Ventricles KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Ion Channels KW - Ion Transport KW - Male KW - Membrane Potentials KW - Mesenchymal Stem Cells KW - Proto-Oncogene Proteins c-kit KW - Stem cells KW - Stem Cells ER - TY - JOUR TI - Differential role of IK and BK potassium channels as mediators of intrinsic and extrinsic apoptotic cell death AU - McFerrin, Michael B. AU - Turner, Kathryn L. AU - Cuddapah, Vishnu Anand AU - Sontheimer, Harald T2 - American Journal of Physiology. Cell Physiology AB - An important event during apoptosis is regulated cell condensation known as apoptotic volume decrease (AVD). Ion channels have emerged as essential regulators of this process mediating the release of K(+) and Cl(-), which together with osmotically obliged water, results in the condensation of cell volume. Using a Grade IV human glioblastoma cell line, we examined the contribution of calcium-activated K(+) channels (K(Ca) channels) to AVD after the addition of either staurosporine (Stsp) or TNF-α-related apoptosis-inducing ligand (TRAIL) to activate the intrinsic or extrinsic pathway of apoptosis, respectively. We show that AVD can be inhibited in both pathways by high extracellular K(+) or the removal of calcium. However, BAPTA-AM was only able to inhibit Stsp-initiated AVD, whereas TRAIL-induced AVD was unaffected. Specific K(Ca) channel inhibitors revealed that Stsp-induced AVD was dependent on K(+) efflux through intermediate-conductance calcium-activated potassium (IK) channels, while TRAIL-induced AVD was mediated by large-conductance calcium-activated potassium (BK) channels. Fura-2 imaging demonstrated that Stsp induced a rapid and modest rise in calcium that was sustained over the course of AVD, while TRAIL produced no detectable rise in global intracellular calcium. Inhibition of IK channels with clotrimazole or 1-[(2-chlorophenyl) diphenylmethyl]-1H-pyrazole (TRAM-34) blocked downstream caspase-3 activation after Stsp addition, while paxilline, a specific BK channel inhibitor, had no effect. Treatment with ionomycin also induced an IK-dependent cell volume decrease. Together these results show that calcium is both necessary and sufficient to achieve volume decrease and that the two major pathways of apoptosis use unique calcium signaling to efflux K(+) through different K(Ca) channels. DA - 2012/11/15/ PY - 2012 DO - 10.1152/ajpcell.00040.2012 DP - PubMed VL - 303 IS - 10 SP - C1070 EP - 1078 J2 - Am J Physiol Cell Physiol LA - eng SN - 1522-1563 L2 - http://www.ncbi.nlm.nih.gov/pubmed/22992678 KW - Apoptosis KW - Calcium KW - Cell Line, Tumor KW - Clotrimazole KW - Enzyme Inhibitors KW - Gene Expression Regulation KW - Glioma KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Ion Channel Gating KW - Large-Conductance Calcium-Activated Potassium Channels KW - Potassium KW - Potassium Channel Blockers KW - Staurosporine KW - TNF-Related Apoptosis-Inducing Ligand ER - TY - JOUR TI - Heteromeric Slick/Slack K+ channels show graded sensitivity to cell volume changes AU - Tejada, Maria A. AU - Hashem, Nadia AU - Calloe, Kirstine AU - Klaerke, Dan A. T2 - PloS One AB - Slick and Slack high-conductance K+ channels are found in the CNS, kidneys, pancreas, among other organs, where they play an important role in cell excitability as well as in ion transport processes. They are both activated by Na+ and Cl- but show a differential regulation by cell volume changes. Slick has been shown to be regulated by cell volume changes, whereas Slack is insensitive. α-subunits of these channels form homomeric as well as heteromeric channels. It is the aim of this work to explore whether the subunit composition of the Slick/Slack heteromeric channel affects the response to osmotic challenges. In order to provide with the adequate water permeability to the cell membrane of Xenopus laevis oocytes, mRNA of aquaporin 1 was co-expressed with homomeric or heteromeric Slick and Slack α-subunits. Oocytes were superfused with hypotonic or hypertonic buffers and changes in currents were measured by two-electrode voltage clamp. This work presents the first heteromeric K+ channel with a characteristic graded sensitivity to small and fast changes in cell volume. Our results show that the cell volume sensitivity of Slick/Slack heteromeric channels is dependent on the number of volume sensitive Slick α-subunits in the tetrameric channels, giving rise to graded cell volume sensitivity. Regulation of the subunit composition of a channel may constitute a novel mechanism to determine volume sensitivity of cells. DA - 2017/// PY - 2017 DO - 10.1371/journal.pone.0169914 DP - PubMed VL - 12 IS - 2 SP - e0169914 J2 - PLoS One LA - eng SN - 1932-6203 L1 - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0169914&type=printable L2 - http://www.ncbi.nlm.nih.gov/pubmed/28222129 KW - Animals KW - Aquaporin 1 KW - Cell Size KW - Humans KW - Hypertonic Solutions KW - Hypotonic Solutions KW - Membrane Potentials KW - Nerve Tissue Proteins KW - Oocytes KW - Osmolar Concentration KW - Patch-Clamp Techniques KW - Potassium Channels KW - Potassium Channels, Sodium-Activated KW - Protein Multimerization KW - Protein Subunits KW - Rats KW - Recombinant Fusion Proteins KW - RNA, Messenger KW - Xenopus laevis ER - TY - JOUR TI - Ca2+-activated K+ channels in human melanoma cells are up-regulated by hypoxia involving hypoxia-inducible factor-1α and the von Hippel-Lindau protein AU - Tajima, Nobuyoshi AU - Schönherr, Kristina AU - Niedling, Susanna AU - Kaatz, Martin AU - Kanno, Hiroshi AU - Schönherr, Roland AU - Heinemann, Stefan H T2 - The Journal of Physiology AB - Under chronic hypoxia, tumour cells undergo adaptive changes involving hypoxia-inducible factors (HIFs). Here we report that ion currents mediated by Ca2+-activated K+ (KCa) channels in human melanoma IGR1 cells are increased by chronic hypoxia (3% O2), as well as by hypoxia mimetics. This increase involves the HIF system as confirmed by overexpression of HIF-1α or the von Hippel-Lindau tumour suppressor gene. Under normoxic conditions the KCa channels in IGR1 cells showed pharmacological characteristics of intermediate conductance KCa subtype IK channels, whereas the subtype SK2 channels were up-regulated under hypoxia, shown with pharmacological tools and with mRNA analysis. Hypoxia increased cell proliferation, but the KCa channel blockers apamin and charybdotoxin slowed down cell growth, particularly under hypoxic conditions. Similar results were obtained for the cell line IGR39 and for acutely isolated cells from a biopsy of a melanoma metastasis. Thus, up-regulation of KCa channels may be a novel mechanism by which HIFs can contribute to the malignant phenotype of human tumour cells. DA - 2006/03/01/ PY - 2006 DO - 10.1113/jphysiol.2005.096818 DP - PubMed Central VL - 571 IS - Pt 2 SP - 349 EP - 359 J2 - J Physiol SN - 0022-3751 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1796787/ Y2 - 2021/05/10/00:11:07 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1796787/pdf/tjp0571-0349.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1796787/ ER - TY - JOUR TI - IK channels are involved in the regulatory volume decrease in human epithelial cells AU - Wang, Jun AU - Morishima, Shigeru AU - Okada, Yasunobu T2 - American Journal of Physiology-Cell Physiology AB - Parallel activation of Ca2+-dependent K+ channels and volume-sensitive Cl− channels is known to be responsible for KCl efflux during regulatory volume decrease (RVD) in human epithelial Intestine 407 cells. The present study was performed to identify the K+ channel type. RT-PCR demonstrated mRNA expression of Ca2+-activated, intermediate conductance K+(IK), but not small conductance K+ (SK1) or large conductance K+ (BK) channels in this cell line. Whole cell recordings showed that ionomycin or hypotonic stress activated inwardly rectifying K+ currents that were reversibly blocked by IK channel blockers [clotrimazole (CLT) and charybdotoxin] but not by SK and BK channel blockers (apamin and iberiotoxin). Inside-out recordings revealed the existence of CLT-sensitive single K+-channel activity, which exhibited an intermediate unitary conductance (30 pS at −100 mV). The channel was activated by cytosolic Ca2+ in inside-out patches and by a hypotonic challenge in cell-attached patches. The RVD was suppressed by CLT, but not by apamin or iberiotoxin. Thus we conclude that the IK channel is involved in the RVD process in these human epithelial cells. DA - 2003/01/01/ PY - 2003 DO - 10.1152/ajpcell.00132.2002 DP - journals-physiology-org.ez.urosario.edu.co (Atypon) VL - 284 IS - 1 SP - C77 EP - C84 J2 - American Journal of Physiology-Cell Physiology SN - 0363-6143 UR - http://journals.physiology.org/doi/full/10.1152/ajpcell.00132.2002 Y2 - 2021/05/10/01:37:22 L1 - http://journals.physiology.org/doi/pdf/10.1152/ajpcell.00132.2002 L2 - http://journals.physiology.org/doi/full/10.1152/ajpcell.00132.2002 ER - TY - JOUR TI - Calcium-activated K+ channels increase cell proliferation independent of K+ conductance AU - Millership, Joanne E. AU - Devor, Daniel C. AU - Hamilton, Kirk L. AU - Balut, Corina M. AU - Bruce, Jason I. E. AU - Fearon, Ian M. T2 - American Journal of Physiology-Cell Physiology AB - The intermediate-conductance calcium-activated potassium channel (IK1) promotes cell proliferation of numerous cell types including endothelial cells, T lymphocytes, and several cancer cell lines. The mechanism underlying IK1-mediated cell proliferation was examined in human embryonic kidney 293 (HEK293) cells expressing recombinant human IK1 (hIK1) channels. Inhibition of hIK1 with TRAM-34 reduced cell proliferation, while expression of hIK1 in HEK293 cells increased proliferation. When HEK293 cells were transfected with a mutant (GYG/AAA) hIK1 channel, which neither conducts K+ ions nor promotes Ca2+ entry, proliferation was increased relative to mock-transfected cells. Furthermore, when HEK293 cells were transfected with a trafficking mutant (L18A/L25A) hIK1 channel, proliferation was also increased relative to control cells. The lack of functional activity of hIK1 mutants at the cell membrane was confirmed by a combination of whole cell patch-clamp electrophysiology and fura-2 imaging to assess store-operated Ca2+ entry and cell surface immunoprecipitation assays. Moreover, in cells expressing hIK1, inhibition of ERK1/2 and JNK kinases, but not of p38 MAP kinase, reduced cell proliferation. We conclude that functional K+ efflux at the plasma membrane and the consequent hyperpolarization and enhanced Ca2+ entry are not necessary for hIK1-induced HEK293 cell proliferation. Rather, our data suggest that hIK1-induced proliferation occurs by a direct interaction with ERK1/2 and JNK signaling pathways. DA - 2010/12/01/ PY - 2010 DO - 10.1152/ajpcell.00274.2010 DP - journals.physiology.org (Atypon) VL - 300 IS - 4 SP - C792 EP - C802 J2 - American Journal of Physiology-Cell Physiology SN - 0363-6143 UR - https://journals.physiology.org/doi/full/10.1152/ajpcell.00274.2010 Y2 - 2021/05/10/01:48:02 L1 - https://journals.physiology.org/doi/pdf/10.1152/ajpcell.00274.2010 L2 - https://journals.physiology.org/doi/full/10.1152/ajpcell.00274.2010 ER - TY - JOUR TI - Role of Membrane Potential in the Regulation of Cell Proliferation and Differentiation AU - Sundelacruz, Sarah AU - Levin, Michael AU - Kaplan, David L. T2 - Stem Cell Reviews and Reports AB - Biophysical signaling, an integral regulator of long-term cell behavior in both excitable and non-excitable cell types, offers enormous potential for modulation of important cell functions. Of particular interest to current regenerative medicine efforts, we review several examples that support the functional role of transmembrane potential (Vmem) in the regulation of proliferation and differentiation. Interestingly, distinct Vmem controls are found in many cancer cell and precursor cell systems, which are known for their proliferative and differentiation capacities, respectively. Collectively, the data demonstrate that bioelectric properties can serve as markers for cell characterization and can control cell mitotic activity, cell cycle progression, and differentiation. The ability to control cell functions by modulating bioelectric properties such as Vmem would be an invaluable tool for directing stem cell behavior toward therapeutic goals. Biophysical properties of stem cells have only recently begun to be studied and are thus in need of further characterization. Understanding the molecular and mechanistic basis of biophysical regulation will point the way toward novel ways to rationally direct cell functions, allowing us to capitalize upon the potential of biophysical signaling for regenerative medicine and tissue engineering. DA - 2009/09/01/ PY - 2009 DO - 10.1007/s12015-009-9080-2 DP - Springer Link VL - 5 IS - 3 SP - 231 EP - 246 J2 - Stem Cell Rev and Rep LA - en SN - 1558-6804 UR - https://doi.org/10.1007/s12015-009-9080-2 Y2 - 2021/05/10/02:00:14 L1 - http://link.springer.com/content/pdf/10.1007%2Fs12015-009-9080-2.pdf ER - TY - JOUR TI - Chloride secretion by the intestinal epithelium: molecular basis and regulatory aspects AU - Barrett, K. E. AU - Keely, S. J. T2 - Annual Review of Physiology AB - Chloride secretion is the major determinant of mucosal hydration throughout the gastrointestinal tract, and chloride transport is also pivotal in the regulation of fluid secretion by organs that drain into the intestine. Moreover, there are pathological consequences if chloride secretion is either reduced or increased such as in cystic fibrosis and secretory diarrhea, respectively. With the molecular cloning of many of the proteins and regulatory factors that make up the chloride secretory mechanism, there have been significant advances in our understanding of this process at the cellular level. Similarly, emerging data have clarified the intercellular relationships that govern the extent of chloride secretion. The goal of our article is to review this area of investigation, with an emphasis on recent developments and their implications for the physiology and pathophysiology of chloride transport. DA - 2000/// PY - 2000 DO - 10.1146/annurev.physiol.62.1.535 DP - PubMed VL - 62 SP - 535 EP - 572 J2 - Annu Rev Physiol LA - eng SN - 0066-4278 ST - Chloride secretion by the intestinal epithelium L2 - http://www.ncbi.nlm.nih.gov/pubmed/10845102 KW - Animals KW - Chlorides KW - Humans KW - Intestinal Mucosa ER - TY - JOUR TI - Modulation of calcium-dependent chloride secretion by basolateral SK4-like channels in a human bronchial cell line AU - Bernard, K. AU - Bogliolo, S. AU - Soriani, O. AU - Ehrenfeld, J. T2 - The Journal of Membrane Biology AB - The human bronchial cell line16HBE14o- was used as a model of airway epithelial cells to study the Ca(2+)-dependent Cl(-) secretion and the identity of K(Ca) channels involved in the generation of a favorable driving force for Cl(-) exit. After ionomycin application, a calcium-activated short-circuit current ( I(sc)) developed, presenting a transient peak followed by a plateau phase. Both phases were inhibited to different degrees by NFA, glybenclamide and NPPB but DIDS was only effective on the peak phase. (86)Rb effluxes through both apical and basolateral membranes were stimulated by calcium, blocked by charybdotoxin, clotrimazole and TPA. 1-EBIO, a SK-channel opener, stimulated (86)Rb effluxes. Block of basolateral K(Ca) channels resulted in I(sc) inhibition but, while reduced, I(sc) was still observed if mucosal Cl(-) was lowered. Among SK family members, only SK4 and SK1 mRNAs were detected by RT-PCR. KCNQ1 mRNAs were also identified, but involvement of K(cAMP) channels in Cl(-) secretion was unlikely, since cAMP application had no effect on (86)Rb effluxes. Moreover, chromanol 293B or clofilium, specific inhibitors of KCNQ1 channels, had no effect on cAMP-dependent I(sc). In conclusion, two distinct components of Cl(-) secretion were identified by a pharmacological approach after a Cai2+ rise. K(Ca) channels presenting the pharmacology of SK4 channels are present on both apical and basolateral membranes, but it is the basolateral SK4-like channels that play a major role in calcium-dependent chloride secretion in 16HBE14o- cells. DA - 2003/11/01/ PY - 2003 DO - 10.1007/s00232-003-0621-3 DP - PubMed VL - 196 IS - 1 SP - 15 EP - 31 J2 - J Membr Biol LA - eng SN - 0022-2631 L2 - http://www.ncbi.nlm.nih.gov/pubmed/14724753 KW - Adaptation, Physiological KW - Bronchi KW - Calcium KW - Cell Line KW - Chlorine KW - Dose-Response Relationship, Drug KW - Electric Conductivity KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Ion Channel Gating KW - Ionomycin KW - Membrane Potentials KW - Potassium Channels KW - Potassium Channels, Calcium-Activated KW - Respiratory Mucosa KW - Rubidium ER - TY - JOUR TI - The Electrical Response to Injury: Molecular Mechanisms and Wound Healing AU - Reid, Brian AU - Zhao, Min T2 - Advances in Wound Care AB - Significance: Natural, endogenous electric fields (EFs) and currents arise spontaneously after wounding of many tissues, especially epithelia, and are necessary for normal healing. This wound electrical activity is a long-lasting and regulated response. Enhancing or inhibiting this electrical activity increases or decreases wound healing, respectively. Cells that are responsible for wound closure such as corneal epithelial cells or skin keratinocytes migrate directionally in EFs of physiological magnitude. However, the mechanisms of how the wound electrical response is initiated and regulated remain unclear. Recent Advances: Wound EFs and currents appear to arise by ion channel up-regulation and redistribution, which are perhaps triggered by an intracellular calcium wave or cell depolarization. We discuss the possibility of stimulation of wound healing via pharmacological enhancement of the wound electric signal by stimulation of ion pumping. Critical Issues: Chronic wounds are a major problem in the elderly and diabetic patient. Any strategy to stimulate wound healing in these patients is desirable. Applying electrical stimulation directly is problematic, but pharmacological enhancement of the wound signal may be a promising strategy. Future Directions: Understanding the molecular regulation of wound electric signals may reveal some fundamental mechanisms in wound healing. Manipulating fluxes of ions and electric currents at wounds might offer new approaches to achieve better wound healing and to heal chronic wounds. DA - 2014/02/01/ PY - 2014 DO - 10.1089/wound.2013.0442 DP - PubMed VL - 3 IS - 2 SP - 184 EP - 201 J2 - Adv Wound Care (New Rochelle) LA - eng SN - 2162-1918 ST - The Electrical Response to Injury L1 - https://europepmc.org/articles/pmc3928722?pdf=render L2 - http://www.ncbi.nlm.nih.gov/pubmed/24761358 ER - TY - JOUR TI - Calcium Oscillatory Behavior and Its Possible Role during Wound Healing in Bovine Corneal Endothelial Cells in Culture AU - Justet, Cristian AU - Chifflet, Silvia AU - Hernandez, Julio A. T2 - BioMed Research International AB - In epithelial layers in culture, immediately after an injury a fast calcium wave (FCW) propagates from the wound borders toward the rest of the monolayer. We show here that similarly to other tissues, during the FCW in bovine corneal endothelial (BCE) cells in culture many cells exhibit calcium oscillations mediated by IP3 signaling. In this study we perform a detailed characterization of this oscillatory behavior and explore its possible role in the process of wound healing. In previous work we showed that, in BCE cells in culture, the healing cells undergo two stages of caspase-dependent apoptosis, at approximately two and eight hours after wounding. We determined that inhibition of the FCW greatly increases the apoptotic rate of the two stages, suggesting that the wave prevents excessive apoptosis of the healing cells. Taking this into account, we investigated the possible participation of the calcium oscillations during the FCW in apoptosis of the healing cells. For this, we employed ARL-67156 (ARL), a weak competitive inhibitor of ecto-ATPases, and the calcium chelator EGTA. We show here that, in healing BCE cells, ARL enhances cellular calcium oscillations during the FCW, while EGTA decreases oscillations. We found that ARL produces a significant decrease (to about half the control value) in the apoptotic index of the first stage of apoptosis, while EGTA increases it. Neither drug noticeably affects the second stage. We have interpreted the effect of ARL on apoptosis as due to the maintenance of moderately risen ATP levels during the FCW, which is in turn the cause for the enhancement of ATP-dependent calcium oscillations. Correspondingly, EGTA would increase the apoptotic index of the first stage by promoting a decrease in the calcium oscillatory rate. The fact that the second stage of apoptosis is not affected by the drugs suggests that the two stages are at least partially subject to different signaling pathways. DA - 2019/02/21/ PY - 2019 DO - 10.1155/2019/8647121 DP - www.hindawi.com VL - 2019 SP - e8647121 LA - en SN - 2314-6133 UR - https://www.hindawi.com/journals/bmri/2019/8647121/ Y2 - 2021/05/10/09:50:27 L1 - https://downloads.hindawi.com/journals/bmri/2019/8647121.pdf L2 - https://www.hindawi.com/journals/bmri/2019/8647121/ ER - TY - JOUR TI - Nonselective cation channel activation during wound healing in the corneal endothelium AU - Watsky, M. A. T2 - The American Journal of Physiology AB - Rabbit corneas were injured by mechanical or thermal trauma. At several time points after wounding, corneal endothelial cells were isolated and their ion channels examined using standard and amphotericin perforated-patch whole cell patch-clamp configurations. Within 15-24 h after mechanical or thermal trauma, a nonselective cation current was observed in 79% of the cells examined that was not present in unwounded or sham-wounded corneas. By 73 h postwounding, the current was present in only 10% of the cells examined. The wound healing-induced current is outwardly rectifying, activates at depolarized voltages, shows no sign of inactivation, and is inhibited by flufenamic acid, quinidine, and acetate. In addition to this new current, it was observed that endothelial cells from freeze-wounded corneas no longer expressed the transient K+ current seen in control, sham, and mechanically wounded corneas. Corneal endothelial superfusion experiments found no significant difference in swelling rates between control and flufenamic acid-superfused wounded corneas, indicating that the wound healing-induced channel is not involved in the stromal hydration maintenance function of the corneal endothelium. DA - 1995/05// PY - 1995 DO - 10.1152/ajpcell.1995.268.5.C1179 DP - PubMed VL - 268 IS - 5 Pt 1 SP - C1179 EP - 1185 J2 - Am J Physiol LA - eng SN - 0002-9513 L2 - http://www.ncbi.nlm.nih.gov/pubmed/7539215 KW - Animals KW - Cations KW - Electrophysiology KW - Endothelium, Corneal KW - Ion Channels KW - Perfusion KW - Rabbits KW - Wound Healing ER - TY - JOUR TI - Ionic Components of Electric Current at Rat Corneal Wounds AU - Vieira, Ana Carolina AU - Reid, Brian AU - Cao, Lin AU - Mannis, Mark J. AU - Schwab, Ivan R. AU - Zhao, Min T2 - PLOS ONE AB - Background Endogenous electric fields and currents occur naturally at wounds and are a strong signal guiding cell migration into the wound to promote healing. Many cells involved in wound healing respond to small physiological electric fields in vitro. It has long been assumed that wound electric fields are produced by passive ion leakage from damaged tissue. Could these fields be actively maintained and regulated as an active wound response? What are the molecular, ionic and cellular mechanisms underlying the wound electric currents? Methodology/Principal Findings Using rat cornea wounds as a model, we measured the dynamic timecourses of individual ion fluxes with ion-selective probes. We also examined chloride channel expression before and after wounding. After wounding, Ca2+ efflux increased steadily whereas K+ showed an initial large efflux which rapidly decreased. Surprisingly, Na+ flux at wounds was inward. A most significant observation was a persistent large influx of Cl−, which had a time course similar to the net wound electric currents we have measured previously. Fixation of the tissues abolished ion fluxes. Pharmacological agents which stimulate ion transport significantly increased flux of Cl−, Na+ and K+. Injury to the cornea caused significant changes in distribution and expression of Cl− channel CLC2. Conclusions/Significance These data suggest that the outward electric currents occurring naturally at corneal wounds are carried mainly by a large influx of chloride ions, and in part by effluxes of calcium and potassium ions. Ca2+ and Cl− fluxes appear to be mainly actively regulated, while K+ flux appears to be largely due to leakage. The dynamic changes of electric currents and specific ion fluxes after wounding suggest that electrical signaling is an active response to injury and offers potential novel approaches to modulate wound healing, for example eye-drops targeting ion transport to aid in the challenging management of non-healing corneal ulcers. DA - 2011/02/25/undefined PY - 2011 DO - 10.1371/journal.pone.0017411 DP - PLoS Journals VL - 6 IS - 2 SP - e17411 J2 - PLOS ONE LA - en SN - 1932-6203 UR - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0017411 Y2 - 2021/05/10/09:59:58 L1 - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0017411&type=printable L2 - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0017411 KW - Chlorides KW - Cornea KW - Electric field KW - Electrodes KW - Epithelial cells KW - Ion transport KW - Vitamin C KW - Wound healing ER - TY - JOUR TI - Ca2+-dependent endoplasmic reticulum stress correlation with astrogliosis involves upregulation of KCa3.1 and inhibition of AKT/mTOR signaling AU - Yu, Zhihua AU - Dou, Fangfang AU - Wang, Yanxia AU - Hou, Lina AU - Chen, Hongzhuan T2 - Journal of Neuroinflammation AB - BACKGROUND: The intermediate-conductance Ca2+-activated K+ channel KCa3.1 was recently shown to control the phenotype switch of reactive astrogliosis (RA) in Alzheimer's disease (AD). METHODS: KCa3.1 channels expression and cell localization in the brains of AD patients and APP/PS1 mice model were measured by immunoblotting and immunostaining. APP/PS1 mice and KCa3.1-/-/APP/PS1 mice were subjected to Morris water maze test to evaluate the spatial memory deficits. Glia activation and neuron loss was measured by immunostaining. Fluo-4AM was used to measure cytosolic Ca2+ level in β-amyloid (Aβ) induced reactive astrocytes in vitro. RESULTS: KCa3.1 expression was markedly associated with endoplasmic reticulum (ER) stress and unfolded protein response (UPR) in both Aβ-stimulated primary astrocytes and brain lysates of AD patients and APP/PS1 AD mice. The KCa3.1 channel was shown to regulate store-operated Ca2+ entry (SOCE) through an interaction with the Ca2+ channel Orai1 in primary astrocytes. Gene deletion or pharmacological blockade of KCa3.1 protected against SOCE-induced Ca2+ overload and ER stress via the protein kinase B (AKT) signaling pathway in astrocytes. Importantly, gene deletion or blockade of KCa3.1 restored AKT/mechanistic target of rapamycin signaling both in vivo and in vitro. Consistent with these in vitro data, expression levels of the ER stress markers 78-kDa glucose-regulated protein and CCAAT/enhancer-binding protein homologous protein, as well as that of the RA marker glial fibrillary acidic protein were increased in APP/PS1 AD mouse model. Elimination of KCa3.1 in KCa3.1-/-/APP/PS1 mice corrected these abnormal responses. Moreover, glial activation and neuroinflammation were attenuated in the hippocampi of KCa3.1-/-/APP/PS1 mice, as compared with APP/PS1 mice. In addition, memory deficits and neuronal loss in APP/PS1 mice were reversed in KCa3.1-/-/APP/PS1 mice. CONCLUSIONS: Overall, these results suggest that KCa3.1 is involved in the regulation of Ca2+ homeostasis in astrocytes and attenuation of the UPR and ER stress, thus contributing to memory deficits and neuronal loss. DA - 2018/11/15/ PY - 2018 DO - 10.1186/s12974-018-1351-x DP - PubMed VL - 15 IS - 1 SP - 316 J2 - J Neuroinflammation LA - eng SN - 1742-2094 L1 - https://jneuroinflammation.biomedcentral.com/track/pdf/10.1186/s12974-018-1351-x.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/30442153 KW - Aged KW - Aged, 80 and over KW - Alzheimer Disease KW - Alzheimer’s disease KW - Amyloid beta-Protein Precursor KW - Animals KW - Animals, Newborn KW - Calcium KW - Cells, Cultured KW - Endoplasmic reticulum stress KW - Endoplasmic Reticulum Stress KW - Female KW - Gene Expression Regulation KW - Gliosis KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - KCa3.1 KW - Male KW - Maze Learning KW - Mice KW - Mice, Inbred C57BL KW - Mice, Transgenic KW - Middle Aged KW - Mouse model KW - Oncogene Protein v-akt KW - Presenilin-1 KW - Signal Transduction KW - Unfolded protein response KW - Up-Regulation ER - TY - JOUR TI - K+ Channel Inhibition Differentially Regulates Migration of Intestinal Epithelial Cells in Inflamed vs. Non-Inflamed Conditions in a PI3K/Akt-Mediated Manner AU - Zundler, Sebastian AU - Caioni, Massimiliano AU - Müller, Martina AU - Strauch, Ulrike AU - Kunst, Claudia AU - Woelfel, Gisela T2 - PLOS ONE AB - Background Potassium channels have been shown to determine wound healing in different tissues, but their role in intestinal epithelial restitution–the rapid closure of superficial wounds by intestinal epithelial cells (IEC)–remains unclear. Methods In this study, the regulation of IEC migration by potassium channel modulation was explored with and without additional epidermal growth factor (EGF) under baseline and interferon-γ (IFN-γ)-pretreated conditions in scratch assays and Boyden chamber assays using the intestinal epithelial cell lines IEC-18 and HT-29. To identify possibly involved subcellular pathways, Western Blot (WB)-analysis of ERK and Akt phosphorylation was conducted and PI3K and ERK inhibitors were used in scratch assays. Furthermore, mRNA-levels of the potassium channel KCNN4 were determined in IEC from patients suffering from inflammatory bowel diseases (IBD). Results Inhibition of Ca2+-dependent potassium channels significantly increased intestinal epithelial restitution, which could not be further promoted by additional EGF. In contrast, inhibition of KCNN4 after pretreatment with IFN-γ led to decreased or unaffected migration. This effect was abolished by EGF. Changes in Akt, but not in ERK phosphorylation strongly correlated with these findings and PI3K but not ERK inhibition abrogated the effect of KCNN4 inhibition. Levels of KCNN4 mRNA were higher in samples from IBD patients compared with controls. Conclusions Taken together, we demonstrate that inhibition of KCNN4 differentially regulates IEC migration in IFN-γ-pretreated vs. non pretreated conditions. Moreover, our data propose that the PI3K signaling cascade is responsible for this differential regulation. Therefore, we present a cellular model that contributes new aspects to epithelial barrier dysfunction in chronic intestinal inflammation, resulting in propagation of inflammation and symptoms like ulcers or diarrhea. DA - 2016/01/29/undefined PY - 2016 DO - 10.1371/journal.pone.0147736 DP - PLoS Journals VL - 11 IS - 1 SP - e0147736 J2 - PLOS ONE LA - en SN - 1932-6203 UR - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0147736 Y2 - 2021/05/10/12:56:32 L1 - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0147736&type=printable L2 - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0147736 KW - Cell migration KW - Epithelial cells KW - ERK signaling cascade KW - Gastrointestinal tract KW - Inflammation KW - Potassium channels KW - Transactivation KW - Wound healing ER - TY - JOUR TI - Slick (Slo2.1), a Rapidly-Gating Sodium-Activated Potassium Channel Inhibited by ATP AU - Bhattacharjee, Arin AU - Joiner, William J. AU - Wu, Meilin AU - Yang, Youshan AU - Sigworth, Fred J. AU - Kaczmarek, Leonard K. T2 - Journal of Neuroscience AB - Neuronal stressors such as hypoxia and firing of action potentials at very high frequencies cause intracellular Na+ to rise and ATP to be consumed faster than it can be regenerated. We report the cloning of a gene encoding a K+ channel, Slick, and demonstrate that functionally it is a hybrid between two classes of K+ channels, Na+-activated (KNa) and ATP-sensitive (KATP) K+ channels. The Slick channel is activated by intracellular Na+ and Cl- and is inhibited by intracellular ATP. Slick is widely expressed in the CNS and is detected in heart. We identify a consensus ATP binding site near the C terminus of the channel that is required for ATP and its nonhydrolyzable analogs to reduce open probability. The convergence of Na+, Cl-, and ATP sensitivity in one channel may endow Slick with the ability to integrate multiple indicators of the metabolic state of a cell and to adjust electrical activity appropriately. DA - 2003/12/17/ PY - 2003 DO - 10.1523/JNEUROSCI.23-37-11681.2003 DP - www.jneurosci.org VL - 23 IS - 37 SP - 11681 EP - 11691 J2 - J. Neurosci. LA - en SN - 0270-6474, 1529-2401 UR - https://www.jneurosci.org/content/23/37/11681 Y2 - 2021/05/10/14:23:53 L1 - https://www.jneurosci.org/content/jneuro/23/37/11681.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/14684870 L2 - https://www.jneurosci.org/content/23/37/11681 KW - channel KW - chloride KW - hippocampus KW - metabolism KW - potassium KW - sodium ER - TY - JOUR TI - Localization of the Na+-activated K+ channel Slick in the rat central nervous system AU - Bhattacharjee, Arin AU - von Hehn, Christian A. A. AU - Mei, Xiaofeng AU - Kaczmarek, Leonard K. T2 - The Journal of Comparative Neurology AB - Na+-activated K+ currents (K(Na)) have been reported in multiple neuronal nuclei and the properties of K(Na) vary in different cell types. We have described previously the distribution of Slack, a Na+-activated K+ channel subunit. Another recently cloned Na+-activated K+ channel is Slick, which differs from Slack in its rapid activation and its sensitivity to intracellular ATP levels. We now report the localization of Slick in the rat central nervous system using in situ and immunohistochemical techniques. As for Slack, we find that Slick is widely distributed in the brain. Specifically, strong hybridization signals and immunoreactivity were found in the brainstem, including auditory neurons such as the medial nucleus of the trapezoid body. As has also been shown for Slack, Slick is expressed in the olfactory bulb, red nucleus, facial nucleus, pontine nucleus, oculomotor nucleus, substantia nigra, deep cerebellar nuclei, vestibular nucleus, and the thalamus. Slick mRNA and protein, however, also are found in certain neurons that do not express Slack. These neurons include those of the hippocampal CA1, CA2, and CA3 regions, the dentate gyrus, supraoptic nucleus, hypothalamus, and cortical layers II, III, and V. These data suggest that Slick may function independently of Slack in these regions. Computer simulations indicate that Slick currents can cause adaptation during prolonged stimuli. Such adaptation allows a neuron to respond to high-frequency stimulation with lower-frequency firing that remains temporally locked to individual stimuli, a property seen in many auditory neurons. Although it is not yet known if Slick and Slack subunits heteromultimerize, the existence of two genes that encode K(Na), that are widely expressed in the nervous system, with both overlapping and nonoverlapping distributions, provides the basis for the reported heterogeneity in the properties of K(Na) from various neurons. DA - 2005/03/28/ PY - 2005 DO - 10.1002/cne.20462 DP - PubMed VL - 484 IS - 1 SP - 80 EP - 92 J2 - J Comp Neurol LA - eng SN - 0021-9967 L2 - http://www.ncbi.nlm.nih.gov/pubmed/15717307 KW - Animals KW - Auditory Pathways KW - Central Nervous System KW - CHO Cells KW - Computer Simulation KW - Cricetinae KW - DNA, Complementary KW - Facial Nerve KW - Immunoblotting KW - Immunohistochemistry KW - In Situ Hybridization KW - Kinetics KW - Models, Neurological KW - Neurons KW - Olfactory Bulb KW - Potassium Channels KW - Potassium Channels, Sodium-Activated KW - Rats KW - Reverse Transcriptase Polymerase Chain Reaction KW - RNA Probes KW - Subcellular Fractions ER - TY - JOUR TI - Cell Volume Changes Regulate Slick (Slo2.1), but Not Slack (Slo2.2) K+ Channels AU - Tejada, Maria A. AU - Stople, Kathleen AU - Bomholtz, Sofia Hammami AU - Meinild, Anne-Kristine AU - Poulsen, Asser Nyander AU - Klaerke, Dan A. T2 - PLOS ONE AB - Slick (Slo2.1) and Slack (Slo2.2) channels belong to the family of high-conductance K+ channels and have been found widely distributed in the CNS. Both channels are activated by Na+ and Cl− and, in addition, Slick channels are regulated by ATP. Therefore, the roles of these channels in regulation of cell excitability as well as ion transport processes, like regulation of cell volume, have been hypothesized. It is the aim of this work to evaluate the sensitivity of Slick and Slack channels to small, fast changes in cell volume and to explore mechanisms, which may explain this type of regulation. For this purpose Slick and Slack channels were co-expressed with aquaporin 1 in Xenopus laevis oocytes and cell volume changes of around 5% were induced by exposure to hypotonic or hypertonic media. Whole-cell currents were measured by two electrode voltage clamp. Our results show that Slick channels are dramatically stimulated (196% of control) by cell swelling and inhibited (57% of control) by a decrease in cell volume. In contrast, Slack channels are totally insensitive to similar cell volume changes. The mechanism underlining the strong volume sensitivity of Slick channels needs to be further explored, however we were able to show that it does not depend on an intact actin cytoskeleton, ATP release or vesicle fusion. In conclusion, Slick channels, in contrast to the similar Slack channels, are the only high-conductance K+ channels strongly sensitive to small changes in cell volume. DA - 2014/10/27/undefined PY - 2014 DO - 10.1371/journal.pone.0110833 DP - PLoS Journals VL - 9 IS - 10 SP - e110833 J2 - PLOS ONE LA - en SN - 1932-6203 UR - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0110833 Y2 - 2021/05/10/14:31:38 L1 - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0110833&type=printable L2 - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0110833 KW - Actins KW - Cell membranes KW - Cytoskeleton KW - Hypertonic KW - Hypotonic KW - Isotonic KW - Potassium channels KW - Xenopus oocytes ER - TY - JOUR TI - Slick (Kcnt2) Sodium-Activated Potassium Channels Limit Peptidergic Nociceptor Excitability and Hyperalgesia AU - Tomasello, Danielle L. AU - Hurley, Edward AU - Wrabetz, Lawrence AU - Bhattacharjee, Arin T2 - Journal of Experimental Neuroscience AB - The Slick (Kcnt2) sodium-activated potassium (KNa) channel is a rapidly gating and weakly voltage-dependent and sodium-dependent potassium channel with no clearly defined physiological function. Within the dorsal root ganglia (DRGs), we show Slick channels are exclusively expressed in small-sized and medium-sized calcitonin gene-related peptide (CGRP)-containing DRG neurons, and a pool of channels are localized to large dense-core vesicles (LDCV)-containing CGRP. We stimulated DRG neurons for CGRP release and found Slick channels contained within CGRP-positive LDCV translocated to the neuronal membrane. Behavioral studies in Slick knockout (KO) mice indicated increased basal heat detection and exacerbated thermal hyperalgesia compared with wild-type littermate controls during neuropathic and chronic inflammatory pain. Electrophysiologic recordings of DRG neurons from Slick KO mice revealed that Slick channels contribute to outward current, propensity to fire action potentials (APs), and to AP properties. Our data suggest that Slick channels restrain the excitability of CGRP-containing neurons, diminishing pain behavior after inflammation and injury. DA - 2017/// PY - 2017 DO - 10.1177/1179069517726996 DP - PubMed VL - 11 SP - 1179069517726996 J2 - J Exp Neurosci LA - eng SN - 1179-0695 L1 - https://journals.sagepub.com/doi/pdf/10.1177/1179069517726996 L2 - http://www.ncbi.nlm.nih.gov/pubmed/28943756 KW - CGRP KW - chronic pain KW - DRG neurons KW - Ion channels KW - thermal nociception ER - TY - JOUR TI - Cardiac metabolic effects of KNa1.2 channel deletion and evidence for its mitochondrial localization AU - Smith, Charles O. AU - Wang, Yves T. AU - Nadtochiy, Sergiy M. AU - Miller, James H. AU - Jonas, Elizabeth A. AU - Dirksen, Robert T. AU - Nehrke, Keith AU - Brookes, Paul S. T2 - FASEB journal: official publication of the Federation of American Societies for Experimental Biology AB - Controversy surrounds the molecular identity of mitochondrial K+ channels that are important for protection against cardiac ischemia-reperfusion injury. Although KNa1.2 (sodium-activated potassium channel encoded by Kcn2) is necessary for cardioprotection by volatile anesthetics, electrophysiological evidence for a channel of this type in mitochondria is lacking. The endogenous physiological role of a potential mito-KNa1.2 channel is also unclear. In this study, single channel patch-clamp of 27 independent cardiac mitochondrial inner membrane (mitoplast) preparations from wild-type (WT) mice yielded 6 channels matching the known ion sensitivity, ion selectivity, pharmacology, and conductance properties of KNa1.2 (slope conductance, 138 ± 1 pS). However, similar experiments on 40 preparations from Kcnt2-/- mice yielded no such channels. The KNa opener bithionol uncoupled respiration in WT but not Kcnt2-/- cardiomyocytes. Furthermore, when oxidizing only fat as substrate, Kcnt2-/- cardiomyocytes and hearts were less responsive to increases in energetic demand. Kcnt2-/- mice also had elevated body fat, but no baseline differences in the cardiac metabolome. These data support the existence of a cardiac mitochondrial KNa1.2 channel, and a role for cardiac KNa1.2 in regulating metabolism under conditions of high energetic demand.-Smith, C. O., Wang, Y. T., Nadtochiy, S. M., Miller, J. H., Jonas, E. A., Dirksen, R. T., Nehrke, K., Brookes, P. S. Cardiac metabolic effects of KNa1.2 channel deletion and evidence for its mitochondrial localization. DA - 2018/06/04/ PY - 2018 DO - 10.1096/fj.201800139R DP - PubMed SP - fj201800139R J2 - FASEB J LA - eng SN - 1530-6860 L1 - https://faseb.onlinelibrary.wiley.com/doi/pdfdirect/10.1096/fj.201800139R L2 - http://www.ncbi.nlm.nih.gov/pubmed/29863912 KW - bithionol KW - patch clamp KW - Slick KW - Slo2.1 ER - TY - ELEC TI - KCNMA1 Encoded Cardiac BK Channels Afford Protection against Ischemia-Reperfusion Injury UR - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0103402 Y2 - 2021/05/10/19:11:05 L2 - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0103402 ER - TY - JOUR TI - Maxi-K Potassium Channels: Form, Function, and Modulation of a Class of Endogenous Regulators of Intracellular Calcium AU - Gribkoff, Valentin K. AU - Starrett, John E. AU - Dworetzky, Steven I. T2 - The Neuroscientist AB - Large-conductance calcium-activated (maxi-K, BK) potassium channels are widely distributed in the brain. Maxi-K channels function as neuronal calcium sensors and contribute to the control of cellular excitability and the regulation of neurotransmitter release. Little is currently known of any significant role of maxi-K channels in the genesis of neurological disease. Recent advances in the molecular biology and pharmacology of these channels have revealed sources of phenotypic variability and demonstrated that they can be successfully modulated by pharmacological agents. A potential role is suggested in the treatment of conditions such as ischemic stroke and cognitive disorders. DA - 2001/04/01/ PY - 2001 DO - 10.1177/107385840100700211 DP - SAGE Journals VL - 7 IS - 2 SP - 166 EP - 177 J2 - Neuroscientist LA - en SN - 1073-8584 ST - Maxi-K Potassium Channels UR - https://doi.org/10.1177/107385840100700211 Y2 - 2021/05/10/19:38:33 KW - BK channel KW - Ischemia KW - Maxi-K channel KW - Neuron KW - Potassium channel KW - Slo channel ER - TY - JOUR TI - MaxiK channel and cell signalling AU - Toro, Ligia AU - Li, Min AU - Zhang, Zhu AU - Singh, Harpreet AU - Wu, Yong AU - Stefani, Enrico T2 - Pflugers Archiv : European journal of physiology AB - The large-conductance Ca2+- and voltage-activated K+ (MaxiK, BK, BKCa, Slo1, KCa1.1) channel role in cell signalling is becoming apparent as we learn how the channel interacts with a multiplicity of proteins not only at the plasma membrane but in intracellular organelles including the endoplasmic reticulum, nucleus and mitochondria. In this review, we focus on the interactions of MaxiK channels with seven transmembrane G-protein coupled receptors, and discuss information suggesting that the channel big C-terminus may act as nucleus of signalling molecules including kinases relevant for cell death and survival. Increasing evidence indicates that the channel is able to associate with a variety of receptors including β-adrenergic receptors, G-protein coupled estrogen receptors, acetylcholine receptors, thromboxane A2 receptors and angiotensin II receptors, which highlights the varied functions that the channel has (or may have) not only in regulating contraction/relaxation of muscle cells or neurotransmission in the brain but also in cell metabolism, proliferation, migration and gene expression. In line with this view, MaxiK channels have been implicated in obesity and in brain, prostate, and mammary cancers. A better understanding of the molecular mechanisms underlying or triggered by MaxiK channel abnormalities like overexpression in certain cancers may lead to new therapeutics to prevent devastating diseases. DA - 2014/05// PY - 2014 DO - 10.1007/s00424-013-1359-0 DP - PubMed Central VL - 466 IS - 5 SP - 875 EP - 886 J2 - Pflugers Arch SN - 0031-6768 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3969412/ Y2 - 2021/05/10/19:50:03 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3969412/pdf/nihms528308.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3969412/ ER - TY - JOUR TI - Biology of corneal endothelial cells in vivo and in vitro AU - Amano, Shiro AU - Kaji, Yuichi AU - Mimura, Tatsuya T2 - Japanese Journal of Ophthalmology DA - 2010/05// PY - 2010 DO - 10.1007/s10384-010-0799-8 DP - PubMed VL - 54 IS - 3 SP - 211 EP - 214 J2 - Jpn J Ophthalmol LA - eng SN - 1613-2246 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20577854 KW - Animals KW - Cellular Senescence KW - Endothelium, Corneal KW - Glycation End Products, Advanced KW - Humans KW - Telomere ER - TY - JOUR TI - Advanced glycation end-products in corneas of patients with keratoconus AU - Dawczynski, Jens AU - Franke, Sibylle AU - Blum, Marcus AU - Kasper, Michael AU - Stein, Günter AU - Strobel, Jürgen T2 - Graefe's Archive for Clinical and Experimental Ophthalmology = Albrecht Von Graefes Archiv Fur Klinische Und Experimentelle Ophthalmologie AB - BACKGROUND: Keratoconus remains a poorly understood yet widespread disease which poses a potential threat to human vision. The underlying mechanisms are still not clear. One possible pathway is increased formation and accumulation of advanced glycation end-products (AGEs) in the cornea. METHODS: Corneas obtained from six patients with keratoconus and from six healthy controls were investigated. An immunohistochemical localisation of the well-known AGE N(epsilon)-carboxymethyllysine (CML) was performed using a polyclonal anti-CML antibody. RESULTS: In the corneas of all six patients with keratoconus, CML immunoreactivity was found in the epithelial as well as in the endothelial cells. The keratocytes also showed a positive reaction. The controls, in contrast, showed very little or no immunoreactivity. CONCLUSION: In the epithelial, stromal and endothelial cells of corneas with keratoconus an accumulation of CML was detected which might play a role in the pathogenesis of keratoconus. DA - 2002/04// PY - 2002 DO - 10.1007/s00417-002-0445-3 DP - PubMed VL - 240 IS - 4 SP - 296 EP - 301 J2 - Graefes Arch Clin Exp Ophthalmol LA - eng SN - 0721-832X L2 - http://www.ncbi.nlm.nih.gov/pubmed/11981644 KW - Adult KW - Aged KW - Cornea KW - Female KW - Glycation End Products, Advanced KW - Humans KW - Immunoenzyme Techniques KW - Keratoconus KW - Lysine KW - Male KW - Middle Aged ER - TY - JOUR TI - Immunolocalization of advanced glycation end products in human diabetic eyes: an immunohistochemical study AU - Kase, Satoru AU - Ishida, Susumu AU - Rao, Narsing Adupa T2 - Journal of Diabetes Mellitus AB - Background: Advanced glycation end-products (AGEs) play a critical role in the pathology of diabetic complications. The aim of this study is to examine the immunolocalization of advanced glycation end products (AGE) and receptor for AGE (RAGE) in human diabetic and non-diabetic donor eyes using immunohistochemistry. Materials and Methods: Eight globes were obtained from human postmortem donors: six diabetic donors and two non-diabetic. Formalin-fixed, paraffin-embedded tissue sections were subjected to immunohistochemistry with anti-AGE, and RAGE antibodies. Results: In eyes from diabetic donors, the blood vessels of the iris and choroid had relatively thickened walls. The ciliary body showed decreased capillaries with hyalinization in the stroma. Neovascularization or proliferative changes were not observed in the tissues. Immunoreactivity for AGE was highly detected in the stroma and blood vessels of the iris, ciliary body, choriocapillaris, choroidal large vessels, and central retinal artery/vein. Immunoreactivity was also detected in the retina, corneal endothelium, and lens. RAGE immunoreactivity was weakly detected in choroidal vessels and Bruch’s membrane. In eyes from non-diabetic donors, AGE was weakly detected in the iris, ciliary body stroma, and choriocapillaris, but RAGE was hardly detected. Conclusion: AGE is highly accumulated in vascularized intraocular tissues of diabetic eyes, suggesting that AGE accumulation may play an important role in the pathogenesis of diabetic vasculopathy. This study indicates that inhibition of AGE formation may be an important therapeutic strategy for suppressing the progression of diabetic ocular complications. DA - 2011/08/31/ PY - 2011 DO - 10.4236/jdm.2011.13009 DP - www.scirp.org VL - 1 IS - 3 SP - 57 EP - 62 LA - en ST - Immunolocalization of advanced glycation end products in human diabetic eyes UR - http://www.scirp.org/Journal/Paperabs.aspx?paperid=7107 Y2 - 2021/05/10/22:24:16 L1 - http://www.scirp.org/journal/PaperDownload.aspx?paperID=7107 L2 - https://www.scirp.org/journal/paperinformation.aspx?paperid=7107 ER - TY - JOUR TI - Immunolocalization of advanced glycation end products in human diabetic eyes: an immunohistochemical study AU - Satoru, Kase AU - Susumu, Ishida AU - Narsing Adupa, Rao T2 - Journal of Diabetes Mellitus AB - Background: Advanced glycation end-products (AGEs) play a critical role in the pathology of diabetic complications. The aim of this study is to examine the immunolocalization of advanced glycation end products (AGE) and receptor for AGE (RAGE) in human diabetic and non-diabetic donor eyes using immunohistochemistry. Materials and Methods: Eight globes were obtained from human postmortem donors: six diabetic donors and two non-diabetic. Formalin-fixed, paraffin-embedded tissue sections were subjected to immunohistochemistry with anti-AGE, and RAGE antibodies. Results: In eyes from diabetic donors, the blood vessels of the iris and choroid had relatively thickened walls. The ciliary body showed decreased capillaries with hyalinization in the stroma. Neovascularization or proliferative changes were not observed in the tissues. Immunoreactivity for AGE was highly detected in the stroma and blood vessels of the iris, ciliary body, choriocapillaris, choroidal large vessels, and central retinal artery/vein. Immunoreactivity was also detected in the retina, corneal endothelium, and lens. RAGE immunoreactivity was weakly detected in choroidal vessels and Bruch’s membrane. In eyes from non-diabetic donors, AGE was weakly detected in the iris, ciliary body stroma, and choriocapillaris, but RAGE was hardly detected. Conclusion: AGE is highly accumulated in vascularized intraocular tissues of diabetic eyes, suggesting that AGE accumulation may play an important role in the pathogenesis of diabetic vasculopathy. This study indicates that inhibition of AGE formation may be an important therapeutic strategy for suppressing the progression of diabetic ocular complications. DA - 2011/08/31/ PY - 2011 DO - 10.4236/jdm.2011.13009 DP - www.scirp.org VL - 2011 LA - en SN - 2160-5858 ST - Immunolocalization of advanced glycation end products in human diabetic eyes UR - http://www.scirp.org/journal/PaperInformation.aspx?PaperID=7107 Y2 - 2021/05/10/22:25:41 L1 - http://www.scirp.org/journal/PaperDownload.aspx?paperID=7107 L2 - https://www.scirp.org/html/5-4300016_7107.htm ER - TY - JOUR TI - Risk factors for various causes of failure in initial corneal grafts AU - Price, Marianne O. AU - Thompson, Robert W. AU - Price, Francis W. T2 - Archives of Ophthalmology (Chicago, Ill.: 1960) AB - OBJECTIVE: To determine the risk factors for specific causes of initial corneal graft failure. METHODS: This study analyzed corneal graft survival rates in a longitudinal noncomparative case series of 3992 consecutive penetrating keratoplasties performed at a single large referral center. Regrafts (n = 352) were excluded from the analysis of risk factors for initial graft failure. Data were collected retrospectively from August 1, 1982, through December 31, 1986, and prospectively from January 1, 1987, through August 31, 1996. Patients were examined preoperatively, at 1, 3, 6, 9, 12, 18, and 24 months posttransplantation, and annually thereafter. Potential risk factors were evaluated individually by Kaplan-Meier survival analysis. Cox proportional hazards regression modeling was then used to investigate the impact of each independent variable, adjusted for the confounding influence of the other independent variables. RESULTS: The use of topical glaucoma medications was a significant risk factor for corneal graft failure by 3 major causes: rejection, endothelial decompensation without a documented immunologic reaction, and ocular surface disease. Deep stromal vascularization was an independent risk factor for rejection failure. Diabetes mellitus, peripheral anterior synechiae, recipient race, and small trephination size were significant risk factors for endothelial failure. CONCLUSION: Independent risk factors differentially impact specific causes of corneal graft failure. DA - 2003/08// PY - 2003 DO - 10.1001/archopht.121.8.1087 DP - PubMed VL - 121 IS - 8 SP - 1087 EP - 1092 J2 - Arch Ophthalmol LA - eng SN - 0003-9950 L1 - https://jamanetwork.com/journals/jamaophthalmology/articlepdf/415567/ECS20205.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/12912684 KW - Adolescent KW - Adult KW - Aged KW - Aged, 80 and over KW - Child KW - Child, Preschool KW - Cornea KW - Female KW - Graft Rejection KW - Graft Survival KW - Humans KW - Infant KW - Keratoplasty, Penetrating KW - Male KW - Middle Aged KW - Proportional Hazards Models KW - Prospective Studies KW - Retrospective Studies KW - Risk Factors ER - TY - JOUR TI - Donor-related risk factors and preoperative recipient-related risk factors for graft failure AU - Yu, Alice L. AU - Kaiser, Michaela AU - Schaumberger, Markus AU - Messmer, Elisabeth AU - Kook, Daniel AU - Welge-Lussen, Ulrich T2 - Cornea AB - PURPOSE: The aim of this study was to evaluate the outcome of penetrating keratoplasties, at the University Eye Hospital, Ludwig-Maximilians-University, Munich, Germany, using organ-cultured donor corneas and to identify preoperative risk factors, which may influence the event of graft failure. METHODS: In this study, 377 medical records of patients, who underwent penetrating keratoplasty between 2001 and 2011, were reviewed. Organ-cultured donor corneas were obtained from the eye bank, Ludwig-Maximilians-University, Munich, Germany. Donor-related and preoperative recipient-related risk factors for graft failure were analyzed by univariate and multivariate analyses. RESULTS: Graft failure occurred in 26% of patients. The following preoperative factors were significantly associated with graft failure by multivariate analyses: high donor age, low donor endothelial cell density, high patient age, indications of infectious keratitis, acute perforation of noninfectious keratitis, prior graft failure, chemical burn, trauma, glaucoma-associated corneal decompensation, high-risk graft indications, corneal edema, anterior chamber lens, diabetes mellitus, atopy, and autoimmune diseases. CONCLUSIONS: This study demonstrated a success rate of 74%, which is consistent with previous studies. Various preoperative recipient-related factors seem to influence the outcome of penetrating keratoplasties, whereas few donor-related factors have a significant association with graft failure. DA - 2014/11// PY - 2014 DO - 10.1097/ICO.0000000000000225 DP - PubMed VL - 33 IS - 11 SP - 1149 EP - 1156 J2 - Cornea LA - eng SN - 1536-4798 L1 - https://epub.ub.uni-muenchen.de/59632/1/00003226-201411000-00005.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/25170580 KW - Adult KW - Age Factors KW - Aged KW - Corneal Diseases KW - Corneal Endothelial Cell Loss KW - Female KW - Graft Rejection KW - Humans KW - Keratoplasty, Penetrating KW - Male KW - Middle Aged KW - Preoperative Period KW - Retrospective Studies KW - Risk Factors KW - Tissue Donors KW - Transplant Recipients KW - Young Adult ER - TY - JOUR TI - Effect of Donor and Recipient Diabetes Status on Descemet Membrane Endothelial Keratoplasty Adherence and Survival AU - Price, Marianne O. AU - Lisek, Marek AU - Feng, Matthew T. AU - Price, Francis W. T2 - Cornea AB - PURPOSE: To evaluate whether donor and/or recipient diabetes status affects the outcomes of Descemet membrane endothelial keratoplasty (DMEK). METHODS: A consecutive, single-center DMEK case series was reviewed. The outcome measures were success of surgeon tissue preparation, air reinjection rate, Kaplan-Meier 4-year graft replacement/failure rate for any reason, and endothelial cell loss. RESULTS: The donor had a history of diabetes in 504 of 1791 cases (28%) and the recipient in 14%. For donors without and with diabetes, the preparation success rate was 99% versus 95% (P < 0.0001), the air reinjection rate was 16% versus 18% (P = 0.19), and the 4-year graft replacement/failure rate was 7% versus 9%, respectively (P = 0.15). Endothelial cell loss was not associated with donor diabetes (P = 0.76). For recipients without and with diabetes, the 4-year graft replacement/failure rate was 7% versus 9% (P = 0.68), and median endothelial cell loss increased from 27% versus 29% at 1 month to 42% versus 48% at 4 years, respectively (P = 0.02). Recipient use of insulin therapy was associated with poorer graft attachment and a higher air reinjection rate (P = 0.0023). CONCLUSIONS: Although donor diabetes was associated with a 5-fold increased risk of tissue preparation failure, it was not significantly associated with air reinjection, graft survival, or endothelial cell loss. This provides reassurance that tissue prepared successfully from donors with diabetes is safe to use for DMEK. Recipient diabetes was associated with increased endothelial cell loss; the potential effect on longer-term graft survival merits further study. DA - 2017/10// PY - 2017 DO - 10.1097/ICO.0000000000001305 DP - PubMed VL - 36 IS - 10 SP - 1184 EP - 1188 J2 - Cornea LA - eng SN - 1536-4798 L2 - http://www.ncbi.nlm.nih.gov/pubmed/28749899 KW - Aged KW - Corneal Endothelial Cell Loss KW - Descemet Stripping Endothelial Keratoplasty KW - Diabetes Mellitus KW - Female KW - Fuchs' Endothelial Dystrophy KW - Graft Survival KW - Humans KW - Male KW - Middle Aged KW - Prospective Studies KW - Tissue Donors KW - Transplant Recipients ER - TY - JOUR TI - Corneal alteration and pathogenesis in diabetes mellitus AU - Zhao, Han AU - He, Yan AU - Ren, Yue-Rong AU - Chen, Bai-Hua T2 - International Journal of Ophthalmology AB - The incidence of diabetes mellitus (DM) and its complications have increased considerably worldwide. Diabetic keratopathy is the major complication of the cornea characterized by delayed corneal wound healing, decreasing corneal epithelial sensitivity, and recurrent corneal ulcers. There is accumulating evidence that diabetic keratopathy is correlated with the hyperglycemic state. Different corneal components may produce different alterations under hyperglycemia. In addition, diabetic nerve alteration may become a novel biomarker of early-stage DM. Abnormalities of the corneal nerve plexus have been associated with diabetic inflammatory states. There is rapidly growing evidence based on investigations of diabetic corneal nerves through in vivo confocal microscopy. Understanding the molecular pathogenesis caused by hyperglycemia may assist in the identification of novel biomarkers, as well as therapeutic targets for early treatment. This review mainly summarizes recent findings on corneal alteration and pathogenesis in DM. DA - 2019/12/18/ PY - 2019 DO - 10.18240/ijo.2019.12.17 DP - PubMed Central VL - 12 IS - 12 SP - 1939 EP - 1950 J2 - Int J Ophthalmol SN - 2222-3959 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6901883/ Y2 - 2021/05/10/23:27:13 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6901883/pdf/ijo-12-12-1939.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6901883/ ER - TY - ELEC TI - ImageJ UR - https://imagej-nih-gov.ez.urosario.edu.co/ij/ Y2 - 2021/05/11/09:28:05 L2 - https://imagej-nih-gov.ez.urosario.edu.co/ij/ ER - TY - JOUR TI - Hyperglycemia Associated Metabolic and Molecular Alterations in Cancer Risk, Progression, Treatment, and Mortality AU - Ramteke, Pranay AU - Deb, Ankita AU - Shepal, Varsha AU - Bhat, Manoj Kumar T2 - Cancers AB - Cancer and diabetes are amongst the leading causes of deaths worldwide. There is an alarming rise in cancer incidences and mortality, with approximately 18.1 million new cases and 9.6 million deaths in 2018. A major contributory but neglected factor for risk of neoplastic transformation is hyperglycemia. Epidemiologically too, lifestyle patterns resulting in high blood glucose level, with or without the role of insulin, are more often correlated with cancer risk, progression, and mortality. The two conditions recurrently exist in comorbidity, and their interplay has rendered treatment regimens more challenging by restricting the choice of drugs, affecting surgical consequences, and having associated fatal complications. Limited comprehensive literature is available on their correlation, and a lack of clarity in understanding in such comorbid conditions contributes to higher mortality rates. Hence, a critical analysis of the elements responsible for enhanced mortality due to hyperglycemia-cancer concomitance is warranted. Given the lifestyle changes in the human population, increasing metabolic disorders, and glucose addiction of cancer cells, hyperglycemia related complications in cancer underline the necessity for further in-depth investigations. This review, therefore, attempts to shed light upon hyperglycemia associated factors in the risk, progression, mortality, and treatment of cancer to highlight important mechanisms and potential therapeutic targets. DA - 2019/09/19/ PY - 2019 DO - 10.3390/cancers11091402 DP - PubMed Central VL - 11 IS - 9 J2 - Cancers (Basel) SN - 2072-6694 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6770430/ Y2 - 2021/05/12/10:46:09 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6770430/pdf/cancers-11-01402.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6770430/ ER - TY - JOUR TI - Hyperglycemia Enhances the Proliferation of Non-Tumorigenic and Malignant Mammary Epithelial Cells through Increased leptin/IGF1R Signaling and Activation of AKT/mTOR AU - Lopez, Rebecca AU - Arumugam, Arunkumar AU - Joseph, Riya AU - Monga, Kanika AU - Boopalan, Thiyagarajan AU - Agullo, Pamela AU - Gutierrez, Christina AU - Nandy, Sushmita AU - Subramani, Ramadevi AU - Rosa, Jose Manuel de la AU - Lakshmanaswamy, Rajkumar T2 - PLOS ONE AB - Obesity and diabetes are associated with increased breast cancer risk and worse disease progression once cancer is diagnosed; however, the exact etiology behind these observations remains to be fully elucidated. Due to the global obesity/diabetes pandemic, it is imperative to understand how these diseases promote and enhance breast cancer and other common cancers. In this study we demonstrate that hyperglycemia promotes breast cancer by altering leptin/IGF1R and AKT/mTOR signaling. To our knowledge, we show for the first time that in breast epithelial cells, hyperglycemia alone directly impacts leptin signaling. Hyperglycemia increased proliferation of both non-tumorigenic and malignant mammary epithelial cells. These observations coincided with increased leptin receptor and IGF1R receptor, as well as, increased levels of GRB2, pJAK2, pSTAT3, pIRS1/2, pAKT, and p-mTOR. Moreover, pJAK2 was almost completely colocalized with leptin receptor under high glucose conditions. These results demonstrate how hyperglycemia can potentially increase the risk of breast cancer in premalignant lesions and enhance cancer progression in malignant cells. DA - 2013/11/18/undefined PY - 2013 DO - 10.1371/journal.pone.0079708 DP - PLoS Journals VL - 8 IS - 11 SP - e79708 J2 - PLOS ONE LA - en SN - 1932-6203 UR - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0079708 Y2 - 2021/05/12/10:57:24 L1 - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0079708&type=printable L2 - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0079708 KW - Apoptosis KW - Breast cancer KW - Cell proliferation KW - Epithelial cells KW - Glucose KW - Glucose signaling KW - Hyperglycemia KW - Leptin ER - TY - JOUR TI - Effects of hyperglycemia on the progression of tumor diseases AU - Li, Wenjie AU - Zhang, Xuehui AU - Sang, Hui AU - Zhou, Ying AU - Shang, Chunyu AU - Wang, Yongqing AU - Zhu, Hong T2 - Journal of Experimental & Clinical Cancer Research AB - Malignant tumors are often multifactorial. Epidemiological studies have shown that hyperglycemia raises the prevalence and mortality of certain malignancies, like breast, liver, bladder, pancreatic, colorectal, endometrial cancers. Hyperglycemia can promote the proliferation, invasion and migration, induce the apoptotic resistance and enhance the chemoresistance of tumor cells. This review focuses on the new findings in the relationship between hyperglycemia and tumor development. DA - 2019/07/23/ PY - 2019 DO - 10.1186/s13046-019-1309-6 DP - BioMed Central VL - 38 IS - 1 SP - 327 J2 - Journal of Experimental & Clinical Cancer Research SN - 1756-9966 UR - https://doi.org/10.1186/s13046-019-1309-6 Y2 - 2021/05/12/11:32:00 L1 - https://jeccr.biomedcentral.com/track/pdf/10.1186/s13046-019-1309-6 L2 - https://jeccr.biomedcentral.com/articles/10.1186/s13046-019-1309-6 KW - Correlation KW - Hyperglycemia KW - Mechanism KW - Progress KW - Tumor cells ER - TY - JOUR TI - Cell cycle regulation in diabetic nephropathy AU - Wolf, Gunter T2 - Kidney International T3 - Diabetic kidney disease research: Where do we stand at the turn of the century? AB - Cell cycle regulation in diabetic nephropathy. Renal hypertrophy is one of the earliest abnormalities of diabetic nephropathy. Although selected cell populations, such as tubulointerstitial fibroblasts, may undergo sustained proliferation in the diabetic environment, most renal cells such as mesangial cells are arrested in the G1-phase of the cell cycle after actively leaving G0-phase and some self-limited early proliferation. High glucose, transforming growth factor-beta (TGF-β), angiotensin II, and probably other factors induce inhibitors of cyclin-dependent kinases (CDK) including p21Cip1 and p27Kip1. These CDK-inhibitors bind to and inactivate G1-phase cyclin/CDK complexes. The consequence is a lack in kinase activity, underphosphorylation of the retinoblastoma gene protein, and a failure to initiate the G1-S-phase transit. The half-life of CDK-inhibitors may also be increased by serine phosphorylation mediated through activated MAP kinases. Treatment of diabetic rats with angiotensin-converting enzyme inhibitors attenuates glomerular hypertrophy and abolishes the glomerular expression of the CDK-inhibitors p16INK4 and p27Kip1, thus indicating that the cell cycle arrest can be therapeutically influenced. Cell cycle proteins may also be involved in these molecular events, leading to a limited degree of tubular apoptosis, which is a feature of diabetic nephropathy. Although not definitively proven, accumulating evidence suggests that early hypertrophy of renal cells may act as pacemaker for subsequent irreversible structural changes, such as glomerulosclerosis and tubulointerstitial fibrosis. Therefore, a better understanding of altered processes of cell cycle regulation is necessary to develop novel therapeutic strategies to prevent diabetic nephropathy. The recent observation that glomerular hypertrophy and proteinuria do not develop in diabetic p21Cip1 knockout mice indicates that this approach is feasible. DA - 2000/09/01/ PY - 2000 DO - 10.1046/j.1523-1755.2000.07710.x DP - ScienceDirect VL - 58 SP - S59 EP - S66 J2 - Kidney International LA - en SN - 0085-2538 UR - https://www.sciencedirect.com/science/article/pii/S0085253815474241 Y2 - 2021/05/12/15:22:50 L1 - https://pdf.sciencedirectassets.com/313527/1-s2.0-S0085253800X89004/1-s2.0-S0085253815474241/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEDcaCXVzLWVhc3QtMSJIMEYCIQCxmCOX%2FqnGTCo1tH1%2B09WAyG%2Fhu0CIZfEz2%2Fcce1PY2gIhANI1XgIXZ%2FmOX6bUY4p5OqiRwQ7TP94%2Bvqp9KJViojfDKr0DCL%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEQAxoMMDU5MDAzNTQ2ODY1IgzG3dwv5R5anndsFhYqkQOjlYDtrIlQS9iZaWSY3WfTnj%2F45VWQMAlX4YpWfVFpDPJ531xNbKULU68rcofnF3EQoVH8h%2Fe%2FId9rxDFnBn9kCc%2BpML1pJnTTYHl7pVwVaeWXTzy10e%2F66m%2Bv%2BBi2eSJwtFbA0D2b6%2FMrlW4hzGiFcakGNGyYy%2B7HhGRapzF1Hu0b0%2F4OJHQAQkdfduiINsgjc4rN2feonS5cf74WyMAgpAkXG0W4IU1ix653baXOifVxOGAByTe%2BOFiP2v1xttRxGb6xL1rAdsw%2Fbyzbz8tQfoLoymEr4p1%2FwlqKGjdXlRE9smgKr4Mgv2L57kEy4LhAa3sdE%2Bdcx5UzCoUsNPsXMJOdFYAToiunbaRgQb%2FP3w8Ge9SLhN30kzeVZ3Whm7oIscJSQwbipgkFZyFq7wFyAnDgWsf5TNJt%2FUUa9cFo1zdjIGb9kyI0ZwivdbdzLaXsZ5A3whIjotko7JIOy%2FbON55ubLu72lkh3KJkfaxV0lIC%2FlraQGc5DPccj9exajAN%2B8CiSn8f%2FQALiZKmthwPXTCqxe%2BEBjrqASRJRV4C1VgjipU5Bi7cadg2Dd7wUBLm%2BKNrnO7u0FhlvXAKPXN8suieaDL%2BIwIgR9QjqrogHRoAyO84j%2BLMgMDIpyM4Sd%2Bbi6Dkd9lySNtcH6RC5xScduZU47Unj7QxRuWu1eD%2FOIwREFGAzsUw%2FfVDpKPKPGc6DF73v2Ya0IePB7UMY1XEoehiRojntXqVvYttsT0o2%2FfrHn1XusplgdI%2BqcwpUDJYfQmKs%2Fw6nSJRZ3Esk6PmXJiWraXXk7%2FsBQMauEkiVOhEgtr88qrH76%2BLGjkAejL%2B8IYm3sKETun19vKWb1cP7t8QBg%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210512T152250Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY3KA5EPHS%2F20210512%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=e99cc3ec498d0b1f833a43824c50411b6c75694e156c02d8446ce43f812ee1a1&hash=686c621c9c4a65e593a42900e5c91b55c55b31c285c708003ee0e1901a0c3079&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0085253815474241&tid=spdf-9af0c5c8-5007-49c7-887e-bad87a5ce066&sid=3806f66c4368824d1a2b51c0b798ba8bbd16gxrqa&type=client L2 - http://www.sciencedirect.com/science/article/pii/S0085253815474241?via%3Dihub KW - cell cycle regulation KW - diabetic nephropathy KW - fibrosis KW - hypertrophy KW - p27kip1 KW - progression of renal disease ER - TY - JOUR TI - Genetic Evidence for a Link Between Glycolysis and DNA Replication AU - Jannière, Laurent AU - Canceill, Danielle AU - Suski, Catherine AU - Kanga, Sophie AU - Dalmais, Bérengère AU - Lestini, Roxane AU - Monnier, Anne-Françoise AU - Chapuis, Jérôme AU - Bolotin, Alexander AU - Titok, Marina AU - Chatelier, Emmanuelle Le AU - Ehrlich, S. Dusko T2 - PLOS ONE AB - BackgroundA challenging goal in biology is to understand how the principal cellular functions are integrated so that cells achieve viability and optimal fitness in a wide range of nutritional conditions.Methodology/Principal FindingsWe report here a tight link between glycolysis and DNA synthesis. The link, discovered during an analysis of suppressors of thermosensitive replication mutants in bacterium Bacillus subtilis, is very strong as some metabolic alterations fully restore viability to replication mutants in which a lethal arrest of DNA synthesis otherwise occurs at a high, restrictive, temperature. Full restoration of viability by such alterations was limited to cells with mutations in three elongation factors (the lagging strand DnaE polymerase, the primase and the helicase) out of a large set of thermosensitive mutants affected in most of the replication proteins. Restoration of viability resulted, at least in part, from maintenance of replication protein activity at high temperature. Physiological studies suggested that this restoration depended on the activity of the three-carbon part of the glycolysis/gluconeogenesis pathway and occurred in both glycolytic and gluconeogenic regimens. Restoration took place abruptly over a narrow range of expression of genes in the three-carbon part of glycolysis. However, the absolute value of this range varied greatly with the allele in question. Finally, restoration of cell viability did not appear to be the result of a decrease in growth rate or an induction of major stress responses.Conclusions/SignificanceOur findings provide the first evidence for a genetic system that connects DNA chain elongation to glycolysis. Its role may be to modulate some aspect of DNA synthesis in response to the energy provided by the environment and the underlying mechanism is discussed. It is proposed that related systems are ubiquitous. DA - 2007/05/16/undefined PY - 2007 DO - 10.1371/journal.pone.0000447 DP - PLoS Journals VL - 2 IS - 5 SP - e447 J2 - PLOS ONE LA - en SN - 1932-6203 UR - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0000447 Y2 - 2021/05/12/16:25:47 L1 - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0000447&type=printable L2 - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0000447 KW - Bacillus subtilis KW - Cell metabolism KW - DNA metabolism KW - DNA replication KW - DNA synthesis KW - Enzyme metabolism KW - Glycolysis KW - Mutation ER - TY - JOUR TI - Cell cycle progression is regulated by intertwined redox oscillators AU - da Veiga Moreira, Jorgelindo AU - Peres, Sabine AU - Steyaert, Jean-Marc AU - Bigan, Erwan AU - Paulevé, Loïc AU - Nogueira, Marcel Levy AU - Schwartz, Laurent T2 - Theoretical Biology and Medical Modelling AB - The different phases of the eukaryotic cell cycle are exceptionally well-preserved phenomena. DNA decompaction, RNA and protein synthesis (in late G1 phase) followed by DNA replication (in S phase) and lipid synthesis (in G2 phase) occur after resting cells (in G0) are committed to proliferate. The G1 phase of the cell cycle is characterized by an increase in the glycolytic metabolism, sustained by high NAD+/NADH ratio. A transient cytosolic acidification occurs, probably due to lactic acid synthesis or ATP hydrolysis, followed by cytosolic alkalinization. A hyperpolarized transmembrane potential is also observed, as result of sodium/potassium pump (NaK-ATPase) activity. During progression of the cell cycle, the Pentose Phosphate Pathway (PPP) is activated by increased NADP+/NADPH ratio, converting glucose 6-phosphate to nucleotide precursors. Then, nucleic acid synthesis and DNA replication occur in S phase. Along with S phase, unpublished results show a cytosolic acidification, probably the result of glutaminolysis occurring during this phase. In G2 phase there is a decrease in NADPH concentration (used for membrane lipid synthesis) and a cytoplasmic alkalinization occurs. Mitochondria hyperfusion matches the cytosolic acidification at late G1/S transition and then triggers ATP synthesis by oxidative phosphorylation. We hypothesize here that the cytosolic pH may coordinate mitochondrial activity and thus the different redox cycles, which in turn control the cell metabolism. DA - 2015/05/29/ PY - 2015 DO - 10.1186/s12976-015-0005-2 DP - BioMed Central VL - 12 IS - 1 SP - 10 J2 - Theoretical Biology and Medical Modelling SN - 1742-4682 UR - https://doi.org/10.1186/s12976-015-0005-2 Y2 - 2021/05/12/16:52:31 L1 - https://tbiomed.biomedcentral.com/track/pdf/10.1186/s12976-015-0005-2 L2 - https://tbiomed.biomedcentral.com/articles/10.1186/s12976-015-0005-2 KW - ATP/ADP KW - CCM KW - Cell cycle KW - HATs KW - HDACs KW - Intracellular pH KW - NAD(P)+/NAD(P)H KW - REDOX ER - TY - JOUR TI - Hyperglycemia-Induced Aberrant Cell Proliferation; A Metabolic Challenge Mediated by Protein O-GlcNAc Modification AU - Nagy, Tamás AU - Fisi, Viktória AU - Frank, Dorottya AU - Kátai, Emese AU - Nagy, Zsófia AU - Miseta, Attila T2 - Cells AB - Chronic hyperglycemia has been associated with an increased prevalence of pathological conditions including cardiovascular disease, cancer, or various disorders of the immune system. In some cases, these associations may be traced back to a common underlying cause, but more often, hyperglycemia and the disturbance in metabolic balance directly facilitate pathological changes in the regular cellular functions. One such cellular function crucial for every living organism is cell cycle regulation/mitotic activity. Although metabolic challenges have long been recognized to influence cell proliferation, the direct impact of diabetes on cell cycle regulatory elements is a relatively uncharted territory. Among other “nutrient sensing” mechanisms, protein O-linked β-N-acetylglucosamine (O-GlcNAc) modification emerged in recent years as a major contributor to the deleterious effects of hyperglycemia. An increasing amount of evidence suggest that O-GlcNAc may significantly influence the cell cycle and cellular proliferation. In our present review, we summarize the current data available on the direct impact of metabolic changes caused by hyperglycemia in pathological conditions associated with cell cycle disorders. We also review published experimental evidence supporting the hypothesis that O-GlcNAc modification may be one of the missing links between metabolic regulation and cellular proliferation. DA - 2019/09// PY - 2019 DO - 10.3390/cells8090999 DP - www.mdpi.com VL - 8 IS - 9 SP - 999 LA - en UR - https://www.mdpi.com/2073-4409/8/9/999 Y2 - 2021/05/12/18:28:54 L1 - https://www.mdpi.com/2073-4409/8/9/999/pdf L2 - https://www.mdpi.com/2073-4409/8/9/999/htm KW - cancer KW - cell cycle KW - diabetes KW - hyperglycemia KW - O-GlcNAc KW - proliferation ER - TY - JOUR TI - O-GlcNAc Signaling Augmentation Protects Human Corneal Endothelial Cells from Oxidative Stress via AKT Pathway Activation AU - Yoon, Chang Ki AU - Yoon, Sam Young AU - Hwang, Jin Sun AU - Shin, Young Joo T2 - Current Eye Research AB - Purpose: To investigate the effect of inhibitor of O-glycosylation on human corneal endothelial cells (HCECs) under oxidative stress.Methods: HCECs were cultured and treated with 10 mM tert-butyl hydroperoxide (tBHP) with or without PUGNAc, a known inhibitor of OGA. Cell viability was assessed. Mitochondrial membrane potential (ΔΨm) was measured. Intracellular Ca2+ levels and mitochondrial Ca2+ levels were measured. Intracellular reactive oxygen species formation was measured. Levels of O-linked β-N-acetylglucosamine (O-GlcNAc), AKT, and pAKT were evaluated by Western blotting.Results: O-GlcNAc augmentation by PUGNAc increased cell viability, attenuated the loss of ΔΨm, and intracellular ROS against tBHP-induced oxidative stress (p < .05). O-GlcNAc augmentation reduced tBHP-induced mitochondrial calcium overload (p < .05) while it did not have any effect on intracellular calcium overload with tBHP. Furthermore, AKT signaling was activated in the cells with O-GlcNAc augmentation.Conclusions: O-GlcNAc signaling augmentation protects HCECs from oxidative stress via activation of AKT pathways. DA - 2020/05/03/ PY - 2020 DO - 10.1080/02713683.2019.1686154 DP - Taylor and Francis+NEJM VL - 45 IS - 5 SP - 556 EP - 562 SN - 0271-3683 UR - https://doi.org/10.1080/02713683.2019.1686154 Y2 - 2021/05/12/20:38:11 L2 - https://www.tandfonline.com/doi/full/10.1080/02713683.2019.1686154?scroll=top&needAccess=true KW - AKT pathway KW - Corneal endothelial cells KW - corneal endothelial wound healing KW - O-linked β-N-acetylglucosamine KW - oxidative stress ER - TY - JOUR TI - The effect of local hyperglycemia on skin cells in vitro and on wound healing in euglycemic rats AU - Kruse, Carla R. AU - Singh, Mansher AU - Sørensen, Jens A. AU - Eriksson, Elof AU - Nuutila, Kristo T2 - Journal of Surgical Research AB -

Abstract

Background

Multiple previous studies have established that high systemic blood glucose concentration impairs skin wound healing. However, the effects of local hyperglycemia on wound healing are not well defined. Comprehensive animal studies and in vitro studies using both fibroblasts and keratinocytes are lacking.

Materials and methods

Primary keratinocytes and fibroblasts were isolated from discarded human tissue, cultured under different concentrations of glucose, and the effect on cell function was examined. In addition, a rat full-thickness wound model was used to topically treat the wounds with different glucose concentrations and the effect on wound closure and re-epithelialization was investigated over time.

Results

The cell viability experiments indicated that both keratinocytes and fibroblasts endure high glucose well and concentrations under 26 mM did not have a remarkable effect on their viability over time. Moderate addition of glucose (10 mM) boosted fibroblast proliferation (6-fold) but did not have an effect on keratinocyte proliferation. In both keratinocytes and fibroblasts, glucose inhibited their migration and already the addition of 5.6-mM glucose had an inhibitory effect. In vivo experiments showed that full-thickness wounds treated with topical glucose had impaired wound closure and lower re-epithelialization rate in comparison to nontreated control wounds. The results also showed that higher glucose concentrations inhibited wound healing more efficiently.

Conclusions

In conclusion, our study indicates that high glucose inhibits both keratinocyte and fibroblast migration as well as wound healing in vivo in a concentration dependent manner.

DA - 2016/12/01/ PY - 2016 DO - 10.1016/j.jss.2016.08.060 DP - www.journalofsurgicalresearch.com VL - 206 IS - 2 SP - 418 EP - 426 J2 - Journal of Surgical Research LA - English SN - 0022-4804, 1095-8673 UR - https://www.journalofsurgicalresearch.com/article/S0022-4804(16)30332-8/abstract Y2 - 2021/05/12/21:43:59 L1 - http://www.journalofsurgicalresearch.com/article/S0022480416303328/pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/27884338 L2 - https://www.journalofsurgicalresearch.com/article/S0022-4804(16)30332-8/fulltext#secsectitle0180 ER - TY - JOUR TI - Perturbations in O-linked β-N-Acetylglucosamine Protein Modification Cause Severe Defects in Mitotic Progression and Cytokinesis* AU - Slawson, Chad AU - Zachara, Natasha E. AU - Vosseller, Keith AU - Cheung, Win D. AU - Lane, M. Daniel AU - Hart, Gerald W. T2 - Journal of Biological Chemistry AB - The dynamic modification of nuclear and cytoplasmic proteins with O-linked β-N-acetylglucosamine (O-GlcNAc) is a regulatory post-translational modification that is rapidly responsive to morphogens, hormones, nutrients, and cellular stress. Here we show that O-GlcNAc is an important regulator of the cell cycle. Increased O-GlcNAc (pharmacologically or genetically) results in growth defects linked to delays in G2/M progression, altered mitotic phosphorylation, and cyclin expression. Overexpression of O-GlcNAcase, the enzyme that removes O-GlcNAc, induces a mitotic exit phenotype accompanied by a delay in mitotic phosphorylation, altered cyclin expression, and pronounced disruption in nuclear organization. Overexpression of the O-GlcNAc transferase, the enzyme that adds O-GlcNAc, results in a polyploid phenotype with faulty cytokinesis. Notably, O-GlcNAc transferase is concentrated at the mitotic spindle and midbody at M phase. These data suggest that dynamic O-GlcNAc processing is a pivotal regulatory component of the cell cycle, controlling cell cycle progression by regulating mitotic phosphorylation, cyclin expression, and cell division. DA - 2005/09/23/ PY - 2005 DO - 10.1074/jbc.M503396200 DP - ScienceDirect VL - 280 IS - 38 SP - 32944 EP - 32956 J2 - Journal of Biological Chemistry LA - en SN - 0021-9258 UR - https://www.sciencedirect.com/science/article/pii/S0021925820791544 Y2 - 2021/05/12/22:00:54 L1 - https://pdf.sciencedirectassets.com/778417/1-s2.0-S0021925820X67032/1-s2.0-S0021925820791544/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjED4aCXVzLWVhc3QtMSJIMEYCIQD%2FpJl1DToQPS2ibF%2BoE%2B3GQMt3Xxn2N8cdscAuxEcyiAIhAMyKoiYPo%2Fst%2FnW2nzwwZaFdGyLe%2BDDjOfsaUzJn1%2F9pKr0DCMb%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEQAxoMMDU5MDAzNTQ2ODY1IgxrL2zFbJLReuII1BkqkQN6dhTrQ22Ek6ECBTGHqaqPSNZ%2BOYSxA3Xe%2BpQ7lgk8hBiWA3fsXOOSoKkBIjeBiCQEGEOgMM99GM9jyZP5JUL2Su0q7QXh2vTcMNv6juWfoXMu80XtK2Eeez3egDVHmfkOPs2lDxVZGHQsYPg14%2FhRbcTXMybGoUfLavhuIa3ZyryeE4MDlo9o1A0waWFCe4BqhVY6wIDkKfmE7hfRtlWuzha9NM9hzqWJxgtUwua3D%2FNTHT41Gg9g2yPLLfUHKLh1pMm4m0%2FStZr58ii3bYbp3YI%2BcqVaYvzfliC9StO2w2TZ9Z86bC6aFTn9JRBL2vrnpaUiSqZG44fn%2BWFQX4qCkz71hFT%2F3poctd9JEfwvc7cLbwUKjyAdMxxsoh9jl9gBzbFucagMKhx6E04HrfUJYuynEjNNE6f9A6%2F4ZOgWyWtB%2BUwVint6W5t9BdnOtQtGysQ1p4AYw8NSbY4FVUOnaLa%2Fknevic6W%2BdjjTRlfV2V8r%2FFWDQypJXT69dkP8cqUv9IAlqO%2BwSAzfl3p8ZMMMDC%2Bi%2FGEBjrqAVo0NHZQqGQcmI7U1ItvDhNkK8MyV7HN%2BGwN%2B5VMezEniCFWGdk0oUsIRzSCsfCaeyadPH4xTLuaDXxUn7VgPMWOxGiC4sdwPBzkWPA0z%2BZhRQ%2BDZw5f11K4siy5sA3ZtQIHKPuShNRtqLlkkfFyI9OuUn2bIqmlaqSlJ2tv3qY623p%2FNt3Ed8ep3jADFleydzNIUsOczT%2BqaTUEgtUPqVWRM%2B%2BFUOkzG7cVdCe1x7uukfeRDyEzDhOYSPv87aYlWImE8ebBmgfzxHMdkuS1%2FWDiWhgEQy%2B%2Fwg3t9EbHkTmpuxixWTRJ%2B4efwQ%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210512T220052Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY5SAWE2VO%2F20210512%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=ba76691d3b01e9d6be9ad5dd3d574a00993225b0372d10491ed4980cc743392c&hash=a97ce898b96f7c0655032b6e43a4fe214452f9238de1e662d9e64a16364a13f5&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0021925820791544&tid=spdf-93162038-e844-4240-ae64-5b402c27b7ed&sid=1e1984174dc7624c6f9a9e241fa8c388ab40gxrqa&type=client L2 - http://www.sciencedirect.com/science/article/pii/S0021925820791544?via%3Dihub ER - TY - JOUR TI - Hyperglycemia impairs osteoblast cell migration and chemotaxis due to a decrease in mitochondrial biogenesis AU - Pahwa, Heena AU - Khan, Md Touseef AU - Sharan, Kunal T2 - Molecular and Cellular Biochemistry AB - Diabetes is associated with an increase in skeletal fragility and risk of fracture. However, the underlying mechanism for the same is not well understood. Specifically, the results from osteoblast cell culture studies are ambiguous due to contradicting reports. The use of supraphysiological concentrations in these studies, unachievable in vivo, might be the reason for the same. Therefore, here, we studied the effect of physiologically relevant levels of high glucose during diabetes (11.1 mM) on MC3T3-E1 osteoblast cell functions. The results showed that high glucose exposure to osteoblast cells increases their differentiation and mineralization without any effect on the proliferation. However, high glucose decreases their migratory potential and chemotaxis with a decrease in the associated cell signaling. Notably, this decrease in cell migration in high glucose conditions was accompanied by aberrant localization of Dynamin 2 in osteoblast cells. Besides, high glucose also caused a shift in mitochondrial dynamics towards the appearance of more fused and lesser fragmented mitochondria, with a concomitant decrease in the expression of DRP1, suggesting decreased mitochondrial biogenesis. In conclusion, here we are reporting for the first time that hyperglycemia causes a reduction in osteoblast cell migration and chemotaxis. This decrease might lead to an inefficient movement of osteoblasts to the erosion site resulting in uneven mineralization and skeletal fragility found in type 2 diabetes patients, in spite of having normal bone mineral density (BMD). DA - 2020/06// PY - 2020 DO - 10.1007/s11010-020-03732-8 DP - PubMed VL - 469 IS - 1-2 SP - 109 EP - 118 J2 - Mol Cell Biochem LA - eng SN - 1573-4919 L2 - http://www.ncbi.nlm.nih.gov/pubmed/32304005 KW - Animals KW - Cell Differentiation KW - Cell Line KW - Cell Movement KW - Chemotaxis KW - Diabetes KW - Diabetes Mellitus, Type 2 KW - Dynamin II KW - Glucose KW - Hyperglycemia KW - Mice KW - Migration KW - Mitochondria KW - Mitochondrial biogenesis KW - Mitochondrial Dynamics KW - Organelle Biogenesis KW - Osteoblast KW - Osteoblasts KW - RNA-Binding Proteins KW - Signal Transduction KW - Skeletal fragility ER - TY - JOUR TI - Measurement of Keratinocyte Migration in Hyperglycemia Media with an Electric Wound-Healing Assay AU - Hsu, Chih-Chin AU - Chen, Carl Pai-Chu AU - Tsai, Wen-Chung AU - Yu, Shin-Ying AU - Wang, Jong-Shyan T2 - The FASEB Journal AB - Background The lifetime risk for a diabetic patient to develop a foot ulcer is about 25%. Prolonged wound-healing process can be observed in diabetic foot ulcer. This study attempted to quantify keratinocyte migration in hyperglycemia media with electric wound-healing assay. Methods Keratinocytes were cultured in Dulbeco's Modified Eagles Medium (DMEM) with 5.6 mM and 33 mM glucose for 7 days, respectively. These cells were inoculated to different wells in the electrode array. An electroporated wound area of 5×10−4 cm2 was created in each well and the healing process was continuously monitored with the electric cell-substrate impedance sensing (ECIS) technique. Western blot for actins in cells at 5.6 mM and 33 mM glucose concentration were also performed. Findings The effective and complete wound healing time in cells at hyperglycemic medium were 7.40±1.9 hours and 13.5±1.6 hours, respectively and were significantly (p = 0.005) slower than those in normal glucose level medium. Decreased actin expression in cells at medium with 33 mM glucose was also observed. Interpretation Impaired cell migration in keratinocytes at DMEM with 33 mM glucose is demonstrated in our measurement. Decreased actin amount may be responsible for the slow keratinocyte movement behavior at hyperglycemic milieu. DA - 2011/// PY - 2011 DO - https://doi.org/10.1096/fasebj.25.1_supplement.680.1 DP - Wiley Online Library VL - 25 IS - S1 SP - 680.1 EP - 680.1 LA - en SN - 1530-6860 UR - https://faseb.onlinelibrary.wiley.com/doi/abs/10.1096/fasebj.25.1_supplement.680.1 Y2 - 2021/05/12/22:47:33 L2 - https://faseb.onlinelibrary.wiley.com/doi/abs/10.1096/fasebj.25.1_supplement.680.1 ER - TY - JOUR TI - Rho-kinase mediates hyperglycemia-induced plasminogen activator inhibitor-1 expression in vascular endothelial cells AU - Rikitake, Yoshiyuki AU - Liao, James K. T2 - Circulation AB - BACKGROUND: Elevated levels of plasminogen activator inhibitor-1 (PAI-1) are associated with myocardial infarction and stroke, especially in patients with diabetes. The induction of PAI-1 expression by hyperglycemia involves oxidative stress and protein kinase C (PKC). However, the mechanism by which hyperglycemia increases PAI-1 expression is unknown. METHODS AND RESULTS: Compared with normoglycemia, exposure of human endothelial cells to hyperglycemia, but not mannitol, increased Rho-kinase activity in a time- and concentration-dependent manner. This increase was inhibited by a PKC inhibitor, GF109203X, and antioxidants N-acetylcysteine (NAC) and reduced form of glutathione (GSH). This correlated with inhibition of hyperglycemia-induced PAI-1 expression by GF109203X, NAC, and GSH. Hyperglycemia-increased PAI-1 mRNA and protein levels were inhibited by Rho-kinase inhibitors hydroxyfasudil and Y27632 and by a dominant-negative mutant of Rho-kinase. The mechanism for this inhibition occurs at the level of gene transcription because Rho-kinase inhibitors repress hyperglycemia-stimulated PAI-1 promoter activity without affecting mRNA stability. Hyperglycemia failed to stimulate Rho-kinase activity and PAI-1 expression in heterozygous ROCK I-knockout murine endothelial cells. CONCLUSIONS: Hyperglycemia stimulates Rho-kinase activity via PKC- and oxidative stress-dependent pathways, leading to increased PAI-1 gene transcription. These results suggest that inhibition of ROCK I may be a novel therapeutic target for preventing thromboembolic complications of diabetes and cardiovascular disease. DA - 2005/06/21/ PY - 2005 DO - 10.1161/CIRCULATIONAHA.105.534024 DP - PubMed VL - 111 IS - 24 SP - 3261 EP - 3268 J2 - Circulation LA - eng SN - 1524-4539 L1 - https://www.ahajournals.org/doi/pdf/10.1161/CIRCULATIONAHA.105.534024 L2 - http://www.ncbi.nlm.nih.gov/pubmed/15956119 KW - Animals KW - Antioxidants KW - Cells, Cultured KW - Endothelium, Vascular KW - Gene Expression Regulation KW - Humans KW - Hyperglycemia KW - Intracellular Signaling Peptides and Proteins KW - Mice KW - Mice, Knockout KW - Oxidative Stress KW - Plasminogen Activator Inhibitor 1 KW - Protein Kinase C KW - Protein-Serine-Threonine Kinases KW - rho-Associated Kinases KW - RNA Stability KW - RNA, Messenger ER - TY - JOUR TI - Effects of Hyperglycemia on Cell Migration and Proliferation, and Phospholipase C1 in Rabbit Corneal Epithelial Cells AU - Akhtar, R. A. AU - Chaouchi, K. M. T2 - Investigative Ophthalmology & Visual Science DA - 2004/05/01/ PY - 2004 DP - iovs.arvojournals.org VL - 45 IS - 13 SP - 3799 EP - 3799 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - https://iovs.arvojournals.org/article.aspx?articleid=2409333 Y2 - 2021/05/12/23:09:39 L2 - https://iovs.arvojournals.org/article.aspx?articleid=2409333 ER - TY - JOUR TI - Enhancement on Primate Corneal Endothelial Cell Survival In Vitro by a ROCK Inhibitor AU - Okumura, Naoki AU - Ueno, Morio AU - Koizumi, Noriko AU - Sakamoto, Yuji AU - Hirata, Kana AU - Hamuro, Junji AU - Kinoshita, Shigeru T2 - Investigative Ophthalmology & Visual Science DA - 2009/08/01/ PY - 2009 DO - 10.1167/iovs.08-2634 DP - iovs.arvojournals.org VL - 50 IS - 8 SP - 3680 EP - 3687 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - https://iovs.arvojournals.org/article.aspx?articleid=2185592 Y2 - 2021/05/12/23:46:58 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/933450/z7g00809003680.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2185592 ER - TY - JOUR TI - Rho-associated kinase inhibitor eye drop treatment as a possible medical treatment for Fuchs corneal dystrophy AU - Koizumi, Noriko AU - Okumura, Naoki AU - Ueno, Morio AU - Nakagawa, Hiroko AU - Hamuro, Junji AU - Kinoshita, Shigeru T2 - Cornea AB - PURPOSE: To report a case of Fuchs corneal dystrophy that was successfully treated by Rho-associated kinase (ROCK) inhibitor eye drops, subsequent to transcorneal freezing of damaged corneal endothelial cells. METHODS: A 52-year-old Japanese man with a diagnosis of late-onset Fuchs corneal dystrophy was referred to our hospital as a candidate for keratoplasty. Best-corrected vision was 20/20 in the right eye and 20/63 in the left eye. Multiple guttae were observed in both eyes. The right cornea was clear, but the left showed severe central edema, with a central corneal thickness of 703 μm. We were unable to perform specular microscopy in the central cornea, but endothelial cells were observed in the midperiphery at a density of 757 cells per square millimeter. The patient was treated by a corneal endothelial denudation in the prepupillary region followed by the topical administration of a selective ROCK inhibitor, Y-27632, as eye drops for 1 week. Follow-up of 24 months is reported. RESULTS: Corneal clarity recovered and vision improved to 20/20 two weeks after the treatment. At 6 months, vision had improved to 20/16 and central corneal thickness measured was 568 μm, significantly lower than its pretreatment value. Endothelial function and vision have been well maintained up to the most recent observation, 24 months after the treatment. The average corneal endothelial density in the central and peripheral cornea was 1549.3 ± 89.7 and 705.0 ± 61.1 cells per square millimeter, respectively. CONCLUSIONS: The case highlights the possibility of medical treatments involving the use of ROCK inhibitor eye drops as an alternative to graft surgery for certain forms of corneal endothelial disease. DA - 2013/08// PY - 2013 DO - 10.1097/ICO.0b013e318285475d DP - PubMed VL - 32 IS - 8 SP - 1167 EP - 1170 J2 - Cornea LA - eng SN - 1536-4798 L2 - http://www.ncbi.nlm.nih.gov/pubmed/23715376 KW - Amides KW - Enzyme Inhibitors KW - Fuchs' Endothelial Dystrophy KW - Humans KW - Male KW - Middle Aged KW - Ophthalmic Solutions KW - Pyridines KW - rho-Associated Kinases KW - Treatment Outcome ER - TY - JOUR TI - Alteration of glucose uptake in cultured human corneal endothelial cells grown in high glucose media via cAMP-dependent pathway AU - Wang, H. Z. AU - Wu, K. Y. AU - Lin, C. P. AU - Fong, J. C. AU - Hong, S. J. T2 - The Kaohsiung Journal of Medical Sciences AB - In this study, cultured human corneal endothelial cells were incubated in media containing various concentrations of glucose at 5 mM, 10 mM, and 25 mM for 2 days. Then, the cellular 2-deoxyglucose uptake and cAMP concentration of cultured human corneal endothelial cells were measured. The results indicated that the activity of cellular glucose uptake of nmole/min/mg protein was decreased gradually from 0.18 (5 mM), 0.10 (10 mM), 0.07 (20 mM) to 0.06 (25 mM) after 2 days incubation with a high concentration of glucose. The glucose uptake in insulin-treated human corneal endothelial cells also exhibited a similar declining effect in high glucose media from 0.30 (5 mM), 0.11 (10 mM), 0.08 (20 mM) to 0.05 (25 mM). The cAMP concentration in human corneal endothelial cells was measured in the presence of high glucose media. It was indicated that the cAMP concentrations of pmole/well in both insulin-treated and non-insulin treated cells were also decreased after increasing the glucose concentration in the media from 73 (5 mM) to 20 (25 mM) and 101 (5 mM) respectively. The cAMP concentration in insulin-treated cells was less than in non-insulin treated cells. This decreasing effect was significantly reversed by the addition of 1 mM dibutyryl-cAMP to the cells for 1 hour in both groups. These results suggest that the diabetic state may decrease the 2-deoxyglucose uptake in human corneal endothelial cells via cAMP-dependent pathway. DA - 1997/09// PY - 1997 DP - PubMed VL - 13 IS - 9 SP - 566 EP - 571 J2 - Kaohsiung J Med Sci LA - eng SN - 1607-551X L2 - http://www.ncbi.nlm.nih.gov/pubmed/9348735 KW - Animals KW - Cells, Cultured KW - Cyclic AMP KW - Deoxyglucose KW - Endothelium, Corneal KW - Glucose Transporter Type 1 KW - Humans KW - Monosaccharide Transport Proteins KW - Rats ER - TY - JOUR TI - The IGF/Insulin-IGFBP Axis in Corneal Development, Wound Healing, and Disease AU - Stuard, Whitney L. AU - Titone, Rossella AU - Robertson, Danielle M. T2 - Frontiers in Endocrinology AB - The insulin-like growth factor (IGF) family plays key roles in growth and development. In the cornea, IGF family members have been implicated in proliferation, differentiation, and migration, critical events that maintain a smooth refracting surface that is essential for vision. The IGF family is composed of multiple ligands, receptors, and ligand binding proteins. Expression of IGF type 1 receptor (IGF-1R), IGF type 2 receptor (IGF-2R), and insulin receptor (INSR) in the cornea has been well characterized, including the presence of the IGF-1R and INSR hybrid (Hybrid-R) in the corneal epithelium. Recent data also indicates that each of these receptors display unique intracellular localization. Thus, in addition to canonical ligand binding at the plasma membrane and the initiation of downstream signaling cascades, IGF-1R, INSR, and Hybrid-R also function to regulate mitochondrial stability and nuclear gene expression. IGF-1 and IGF-2, two of three principal ligands, are polypeptide growth factors that function in all cellular layers of the cornea. Unlike IGF-1 and IGF-2, the hormone insulin plays a unique role in the cornea, different from many other tissues in the body. In the corneal epithelium, insulin is not required for glucose uptake, due to constitutive activation of the glucose transporter, GLUT1. However, insulin is needed for the regulation of metabolism, circadian rhythm, autophagy, proliferation, and migration after wounding. There is conflicting evidence regarding expression of the six IGF-binding proteins (IGFBPs), which function primarily to sequester IGF ligands. Within the cornea, IGFBP-2 and IGFBP-3 have identified roles in tissue homeostasis. While IGFBP-3 regulates growth control and intracellular receptor localization in the corneal epithelium, both IGFBP-2 and IGFBP-3 function in corneal fibroblast differentiation and myofibroblast proliferation, key events in stromal wound healing. IGFBP-2 has also been linked to cellular overgrowth in pterygium. There is a clear role for IGF family members in regulating tissue homeostasis in the cornea. This review summarizes what is known regarding the role of IGF and related proteins in corneal development, during wound healing, and in the pathophysiology of disease. Finally, we highlight key areas of research that are in need of future study. DA - 2020/// PY - 2020 DO - 10.3389/fendo.2020.00024 DP - Frontiers VL - 11 J2 - Front. Endocrinol. LA - English SN - 1664-2392 UR - https://www.frontiersin.org/articles/10.3389/fendo.2020.00024/full Y2 - 2021/05/13/21:59:11 L1 - https://www.frontiersin.org/articles/10.3389/fendo.2020.00024/pdf KW - Cornea KW - Hybrid-R KW - IGF-1 KW - IGF-1R KW - IGFBP-2 KW - IGFBP-3 KW - INSR ER - TY - JOUR TI - Glucose Transporter 1 Expression in Corneal Wound Repair under High Serum Glucose Level AU - Takahashi, Hiroshi AU - Ohara, Kunitoshi AU - Ohmura, Takeo AU - Takahashi, Ryoki AU - Zieske, James D T2 - Japanese Journal of Ophthalmology AB - Purpose: To determine glucose transporter (GLUT) 1 mRNA and protein expression during corneal epithelial wound healing in diabetic rat. Methods: Diabetes mellitus was induced by intraperitoneal injection of streptozotocin. At 10 days after injection, unilateral 3-mm epithelial debridement was carried out in the central cornea. At 2, 4, 6, and 24 hours after wounding, whole corneal epithelium was collected and GLUT1 protein and mRNA levels were determined by Western blotting and reverse transcription-polymerase chain reaction, respectively. Sugar content in collected samples was measured by the Anthrone reaction. Normal rats were used as controls. Results: Glucose transporter 1 protein and mRNA levels in unwounded cornea were similarly low in the diabetic and control groups. Healing of corneal wounds was slower in diabetic rats than in controls. After wounding, GLUT1 mRNA and protein expression in both groups were similarly enhanced compared to unwounded epithelium. Sugar content at all time points did not show significant alteration in any group, although in diabetic rats it was significantly higher than in controls throughout the time course. Conclusion: Glucose transporter 1 expression in diabetic rat cornea showed little difference from that in normal rat cornea, suggesting minimal influence of GLUT1 on the delayed healing of diabetic corneal wounds. DA - 2000/09/01/ PY - 2000 DO - 10.1016/S0021-5155(00)00222-7 DP - ScienceDirect VL - 44 IS - 5 SP - 470 EP - 474 J2 - Japanese Journal of Ophthalmology LA - en SN - 0021-5155 UR - https://www.sciencedirect.com/science/article/pii/S0021515500002227 Y2 - 2021/05/13/23:47:23 L2 - http://www.sciencedirect.com/science/article/abs/pii/S0021515500002227?via%3Dihub KW - Cornea KW - diabetes KW - glucose transporter KW - wound repair ER - TY - ELEC TI - STRING: functional protein association networks UR - https://string-db.org/ Y2 - 2021/05/14/00:07:07 L2 - https://string-db.org/ ER - TY - JOUR TI - Expression of Vascular Endothelial Growth Factor and Its Receptors in Inflamed and Vascularized Human Corneas AU - Philipp, Wolfgang AU - Speicher, Lilly AU - Humpel, Christian T2 - Investigative Ophthalmology & Visual Science DA - 2000/08/01/ PY - 2000 DP - iovs.arvojournals.org VL - 41 IS - 9 SP - 2514 EP - 2522 J2 - Invest. Ophthalmol. Vis. Sci. LA - en SN - 1552-5783 UR - https://iovs.arvojournals.org/article.aspx?articleid=2162302 Y2 - 2021/05/14/11:21:28 L1 - https://iovs.arvojournals.org/arvo/content_public/journal/iovs/933219/7g080002514.pdf L2 - https://iovs.arvojournals.org/article.aspx?articleid=2162302 ER - TY - JOUR TI - Modeling Diabetic Corneal Neuropathy in a 3D In Vitro Cornea System AU - Deardorff, Phillip M. AU - McKay, Tina B. AU - Wang, Siran AU - Ghezzi, Chiara E. AU - Cairns, Dana M. AU - Abbott, Rosalyn D. AU - Funderburgh, James L. AU - Kenyon, Kenneth R. AU - Kaplan, David L. T2 - Scientific Reports AB - Diabetes mellitus is a disease caused by innate or acquired insulin deficiency, resulting in altered glucose metabolism and high blood glucose levels. Chronic hyperglycemia is linked to development of several ocular pathologies affecting the anterior segment, including diabetic corneal neuropathy and keratopathy, neovascular glaucoma, edema, and cataracts leading to significant visual defects. Due to increasing disease prevalence, related medical care costs, and visual impairment resulting from diabetes, a need has arisen to devise alternative systems to study molecular mechanisms involved in disease onset and progression. In our current study, we applied a novel 3D in vitro model of the human cornea comprising of epithelial, stromal, and neuronal components cultured in silk scaffolds to study the pathological effects of hyperglycemia on development of diabetic corneal neuropathy. Specifically, exposure to sustained levels of high glucose, ranging from 35 mM to 45 mM, were applied to determine concentration-dependent effects on nerve morphology, length and density of axons, and expression of metabolic enzymes involved in glucose metabolism. By comparing these metrics to in vivo studies, we have developed a functional 3D in vitro model for diabetic corneal neuropathy as a means to investigate corneal pathophysiology resulting from prolonged exposure to hyperglycemia. DA - 2018/11/23/ PY - 2018 DO - 10.1038/s41598-018-35917-z DP - www.nature.com VL - 8 IS - 1 SP - 17294 LA - en SN - 2045-2322 UR - https://www.nature.com/articles/s41598-018-35917-z Y2 - 2021/05/15/01:12:05 L1 - https://www.nature.com/articles/s41598-018-35917-z.pdf L2 - https://www.nature.com/articles/s41598-018-35917-z ER - TY - JOUR TI - Evaluation of a New Measure of Blood Glucose Variability in Diabetes AU - Kovatchev, Boris P. AU - Otto, Erik AU - Cox, Daniel AU - Gonder-Frederick, Linda AU - Clarke, William T2 - Diabetes Care AB - OBJECTIVE—Recent studies show the importance of controlling blood glucose variability in relationship to both reducing hypoglycemia and attenuating the risk for cardiovascular and behavioral complications due to hyperglycemia. It is therefore important to design variability measures that are equally predictive of low and high blood glucose excursions. RESEARCH DESIGN AND METHODS—We introduce the average daily risk range (ADRR), a variability measure computed from routine self-monitored blood glucose (SMBG) data. The ADRR was constructed using a development dataset for 39 and 31 adults with type 1 and type 2 diabetes, respectively. The formula was then fixed, and the ADRR was compared against other variability measures using an independent validation dataset containing ∼4 months of SMBG for 254 and 81 adults with type 1 and type 2 diabetes. RESULTS—From the 1st month of validation SMBG data, we computed the ADRR, blood glucose SD and coefficient of variation, daily blood glucose range and interquartile range, mean amplitude of glycemic excursion, M-value, and lability index. Then all measures were tested as predictors of low blood glucose (<2.2 mmol/l; <3.9 mmol/l) and high (>10 mmol/l; >22.2 mmol/l) events in the subsequent 3 months. The ADRR was the best predictor of both hypoglycemia and hyperglycemia, with a 6-fold increase in the likelihood of hypoglycemia and 3.5-fold increase in the likelihood of hyperglycemia across its risk categories. CONCLUSIONS—In a large SMBG database, the ADRR showed strong association with subsequent out-of-control glucose readings. Compared with other variability measures, the ADRR demonstrated a superior balance of sensitivity to predicting both hypoglycemia and hyperglycemia. This prediction was independent from type of diabetes. DA - 2006/11/01/ PY - 2006 DO - 10.2337/dc06-1085 DP - care.diabetesjournals.org VL - 29 IS - 11 SP - 2433 EP - 2438 LA - en SN - 0149-5992, 1935-5548 UR - https://care.diabetesjournals.org/content/29/11/2433 Y2 - 2021/05/15/01:22:08 L1 - https://care.diabetesjournals.org/content/diacare/29/11/2433.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/17065680 L2 - https://care.diabetesjournals.org/content/29/11/2433 KW - ADRR, average daily risk range KW - HBGI, high blood glucose index KW - LBGI, low blood glucose index KW - MAGE, mean amplitude of glucose excursions KW - SMBG, self-monitored blood glucose ER - TY - JOUR TI - Preventive (myoglobin, transferrin) and scavenging (superoxide dismutase, glutathione peroxidase) anti-oxidative properties of raw liquid extract of Morinda lucida leaf in the traditional treatment of Plasmodium infection AU - Olaniyan, Mathew Folaranmi AU - Babatunde, Elizabeth Moyinoluwa T2 - Journal of Natural Science, Biology, and Medicine AB - BACKGROUND: Liquid extract of Morinda lucida leaf has been demonstrated to have antiplasmodial activities. Some phytochemicals act as preventive and or scavenging antioxidants. This study aimed to investigate the preventative and scavenging properties of the raw liquid extract of M. lucida leaf using plasma myoglobin, transferrin, superoxide dismutase (SOD), and glutathione (GSH) peroxidase. MATERIALS AND METHODS: Forty-eight Plasmodium-infected patients aged 29-47 years that have not been treated with any antimalaria medication but have decided to be treated traditionally using M. lucida leaf extract were recruited from 15 traditional homes in ATISBO, Saki-East, and Saki-West local government areas of Oke-Ogun - the Northern part of Oyo State-Nigeria. Identification of Plasmodium in the blood of the test and normal control subjects were carried out by Giemsha thick film technique. Packed cell volume, total bile acids, blood glucose, blood pressure, plasma myoglobin, transferrin, SOD, and GSH peroxidase (GPx) were evaluated in the normal control subjects and in the Plasmodium-infected patients before and after the treatment with raw liquid extract of M. lucida leaf. RESULTS: A significant (P < 0.05) biochemical alterations were observed in the plasma values of transferrin, SOD, and GPx in the Plasmodium-infected patients when compared with the normal control subjects and after treatment with the raw liquid extract of M. lucida leaf. CONCLUSION: Our study supports the possible preventative and scavenging antioxidative effect of the raw liquid extract of M. lucida leaf in the traditional treatment of Plasmodium infection. DA - 2016/06//Jan- undefined PY - 2016 DO - 10.4103/0976-9668.175068 DP - PubMed VL - 7 IS - 1 SP - 47 EP - 53 J2 - J Nat Sci Biol Med LA - eng SN - 0976-9668 L2 - http://www.ncbi.nlm.nih.gov/pubmed/27003969 KW - Morinda lucida KW - Plasmodium infection KW - preventive antioxidants KW - scavenging antioxidants ER - TY - JOUR TI - Selenium: its role as antioxidant in human health AU - Tinggi, Ujang T2 - Environmental Health and Preventive Medicine AB - Selenium (Se) is an essential trace element, and its low status in humans has been linked to increased risk of various diseases, such as cancer and heart disease. In recent years, Se research has attracted tremendous interest because of its important role in antioxidant selenoproteins for protection against oxidative stress initiated by excess reactive oxygen species (ROS) and reactive nitrogen species (NOS). The synthesis of selenoproteins requires a unique incorporation of amino acid selenocysteine (Sec) into proteins directed by the UGA codon, which is also a termination codon. Interest in Se research has led to the discovery of at least 30 selenoproteins; however, the biochemical functional roles of some of these selenoproteins are still unknown. Besides in the form of selenoproteins, Se can exist in many different chemical forms in biological materials either as organic Se compounds, such as selenomethionine and dimethylselenide, and inorganic selenites and selenates. In foods, Se is predominantly present as selenomethionine, which is an important source of dietary Se in humans, and also as a chemical form that is commonly used for Se supplements in clinical trials. Concern for potential deficiency diseases associated with low Se status has led to the establishment of the recommended daily requirements for Se in many countries. However, excess Se intakes through supplementation and its potential misuse as health therapy could also pose a risk of adverse health effects if its use is not properly regulated. DA - 2008/03// PY - 2008 DO - 10.1007/s12199-007-0019-4 DP - PubMed Central VL - 13 IS - 2 SP - 102 EP - 108 J2 - Environ Health Prev Med SN - 1342-078X ST - Selenium UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2698273/ Y2 - 2021/05/15/09:26:03 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2698273/pdf/12199_2007_Article_19.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2698273/ ER - TY - JOUR TI - Calmodulin Mediates Calcium-dependent Activation of the Intermediate Conductance KCa Channel,IKCa1 * AU - Fanger, Christopher M. AU - Ghanshani, Sanjiv AU - Logsdon, Naomi J. AU - Rauer, Heiko AU - Kalman, Katalin AU - Zhou, Jianming AU - Beckingham, Kathy AU - Chandy, K. George AU - Cahalan, Michael D. AU - Aiyar, Jayashree T2 - Journal of Biological Chemistry AB - Small and intermediate conductance Ca2+-activated K+ channels play a crucial role in hyperpolarizing the membrane potential of excitable and nonexcitable cells. These channels are exquisitely sensitive to cytoplasmic Ca2+, yet their protein-coding regions do not contain consensus Ca2+-binding motifs. We investigated the involvement of an accessory protein in the Ca2+-dependent gating of hIKCa1, a human intermediate conductance channel expressed in peripheral tissues. Cal- modulin was found to interact strongly with the cytoplasmic carboxyl (C)-tail of hIKCa1 in a yeast two-hybrid system. Deletion analyses defined a requirement for the first 62 amino acids of the C-tail, and the binding of calmodulin to this region did not require Ca2+. The C-tail ofhSKCa3, a human neuronal small conductance channel, also bound calmodulin, whereas that of a voltage-gated K+channel, mKv1.3, did not. Calmodulin co-precipitated with the channel in cell lines transfected with hIKCa1, but not with mKv1.3-transfected lines. A mutant calmodulin, defective in Ca2+ sensing but retaining binding to the channel, dramatically reduced current amplitudes when co-expressed withhIKCa1 in mammalian cells. Co-expression with varying amounts of wild-type and mutant calmodulin resulted in a dominant-negative suppression of current, consistent with four calmodulin molecules being associated with the channel. Taken together, our results suggest that Ca2+-calmodulin-induced conformational changes in all four subunits are necessary for the channel to open. DA - 1999/02/26/ PY - 1999 DO - 10.1074/jbc.274.9.5746 DP - ScienceDirect VL - 274 IS - 9 SP - 5746 EP - 5754 J2 - Journal of Biological Chemistry LA - en SN - 0021-9258 UR - https://www.sciencedirect.com/science/article/pii/S0021925819877189 Y2 - 2021/05/15/11:32:45 L1 - https://pdf.sciencedirectassets.com/778417/1-s2.0-S0021925819X80874/1-s2.0-S0021925819877189/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEHsaCXVzLWVhc3QtMSJGMEQCIATIyy5dcuYveJLw64a5YQ2uOyOT%2FTSA5dXDFsV76Ks%2BAiAReRxINSb9cQEsbegU%2FfAei9o%2BDEMjBiWg5qG34SPNiyq0AwgTEAMaDDA1OTAwMzU0Njg2NSIM8kPZdPG7JKoIigutKpEDT4O64gXv5QFqJZZbBkXVXLo2SjqEDv1zo3%2F8dqGYq2s6WTkKvlW%2FSh1MINSwYAf2JbtbYNVNMJy%2BX0HesHlyyASo7s8WyMJz6b8%2BJ%2FLyyQUEBNaa6jqEafYdE%2BNfvdvAVvFEJn9MpBKO0UtCBh5fCQzjyMrLcrlI3mkmTmvHCHc3ZJXMpA4c8zzhT1heclO2TwnKILkKzghR2OKehMLy2L4zXNGgicsX3a0wUPg4f3npi3fb6TS1iHRlER4keKUuQ8L7RL1%2BJzcwkExA1efquyMJXTscSvJ5q6Ger%2FAcPiqWpyREb5NUwvVzEluMLZaB8eI%2F7%2BWyYVBn9q3%2BOvaIxKUiRknPzKlLM50GzFZi4xcdFkN5gWLrSw9f%2BRfsqazpeOc9VHlo%2BZS3zvd9zx6HIZSDHr49wdjCdtY%2BwWdgVpdeYaGmui%2BOWdy7pqkOWg5C%2Fe6iu4oyFNSsDiqlu53s0UDPYSmJgBid%2BuHnHjTx5ZA6AFN%2BFLo79Jkc7IgeWuuqiy4mJjYRyi8ALSfDoP2P9uEwmsP%2BhAY67AESrgG4WZ5rjRrRCdGH7dTskZxQWduhB6Ia0iOMrDOv2MuGwS72Tel7YjZuEbGZkBeNsBEM4bxlwDJVRBjqtiDSdz8%2FEhAfOIESdTKdNThxqwFy9co06tLBg%2B4nIrhjI6zDn42l%2FMr%2BFSwUGN3gVZeowA6o6bXQAhyZvm4HyqmICgKdqiwOuYUvX3i%2FMsAMV6lAICS4Oqm1Y4l3HWmps5JnhfwUy1C7HATgUHjLWEZKqs86HteJnyE%2BZgSIGGFs8NIt2xIvjTmJ%2BaF2XqkaGsiCq31exzBN%2FDZNP2O6gpS9ac98HU07b6NY6rfmKQ%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210515T113246Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYV7TI6KFA%2F20210515%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=68fe3c33581d39f8f67ee810f2879acf18455dc956361578533f309d3eadfd99&hash=d89e105943bcf9ea1c664a9acaeb9fe5ca73c60b9ac0469f4bda7d90b082123c&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0021925819877189&tid=spdf-5efa89c7-b100-4337-a0c6-025f60af872d&sid=95f498c32804524c593890b7b384a56473c9gxrqa&type=client L2 - http://www.sciencedirect.com/science/article/pii/S0021925819877189?via%3Dihub ER - TY - JOUR TI - Therapeutic potential of KCa3.1 blockers: an overview of recent advances, and promising trends AU - Wulff, Heike AU - Castle, Neil A. T2 - Expert Review of Clinical Pharmacology AB - The calcium-activated potassium channel KCa3.1 regulates membrane potential and calcium signaling in erythrocytes, activated T and B cells, macrophages, microglia, vascular endothelium, epithelia, and proliferating vascular smooth muscle cells and fibroblasts. KCa3.1 has therefore been suggested as a potential therapeutic target for diseases such as sickle cell anemia, asthma, coronary restenosis after angioplasty, atherosclerosis, kidney fibrosis and autoimmunity, where activation and excessive proliferation of one or more of these cell types is involved in the pathology. This article will review KCa3.1’s physiology and pharmacology and critically examine the available preclinical and clinical data validating KCa3.1 as a therapeutic target. DA - 2010/05// PY - 2010 DO - 10.1586/ecp.10.11 DP - PubMed Central VL - 3 IS - 3 SP - 385 EP - 396 J2 - Expert Rev Clin Pharmacol SN - 1751-2433 ST - Therapeutic potential of KCa3.1 blockers UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3347644/ Y2 - 2021/05/15/11:37:25 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3347644/pdf/nihms-370560.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3347644/ ER - TY - JOUR TI - Up-regulation of the IKCa1 potassium channel during T-cell activation. Molecular mechanism and functional consequences AU - Ghanshani, S. AU - Wulff, H. AU - Miller, M. J. AU - Rohm, H. AU - Neben, A. AU - Gutman, G. A. AU - Cahalan, M. D. AU - Chandy, K. G. T2 - The Journal of Biological Chemistry AB - We used whole cell recording to evaluate functional expression of the intermediate conductance Ca(2+)-activated K(+) channel, IKCa1, in response to various mitogenic stimuli. One to two days following engagement of T-cell receptors to trigger both PKC- and Ca(2+)-dependent events, IKCa1 expression increased from an average of 8 to 300-800 channels/cell. Selective stimulation of the PKC pathway resulted in equivalent up-regulation, whereas a calcium ionophore was relatively ineffective. Enhancement in IKCa1 mRNA levels paralleled the increased channel number. The genomic organization of IKCa1, SKCa2, and SKCa3 were defined, and IK(Ca) and SK(Ca) genes were found to have a remarkably similar intron-exon structure. Mitogens enhanced IKCa1 promoter activity proportional to the increase in IKCa1 mRNA, suggesting that transcriptional mechanisms underlie channel up-regulation. Mutation of motifs for AP1 and Ikaros-2 in the promoter abolished this induction. Selective Kv1.3 inhibitors ShK-Dap(22), margatoxin, and correolide suppressed mitogenesis of resting T-cells but not preactivated T-cells with up-regulated IKCa1 channel expression. Selectively blocking IKCa1 channels with clotrimazole or TRAM-34 suppressed mitogenesis of preactivated lymphocytes, whereas resting T-cells were less sensitive. Thus, Kv1.3 channels are essential for activation of quiescent cells, but signaling through the PKC pathway enhances expression of IKCa1 channels that are required for continued proliferation. DA - 2000/11/24/ PY - 2000 DO - 10.1074/jbc.M003941200 DP - PubMed VL - 275 IS - 47 SP - 37137 EP - 37149 J2 - J Biol Chem LA - eng SN - 0021-9258 L1 - https://www.jbc.org/content/275/47/37137.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/10961988 KW - Calcium Channel Blockers KW - Calcium Channels KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Lymphocyte Activation KW - Mitogens KW - Models, Biological KW - Molecular Sequence Data KW - Phytohemagglutinins KW - Potassium Channels KW - Promoter Regions, Genetic KW - Pyrazoles KW - Signal Transduction KW - T-Lymphocytes KW - Tetradecanoylphorbol Acetate KW - Transcription, Genetic KW - Up-Regulation ER - TY - JOUR TI - Selective blockade of the intermediate-conductance Ca2+-activated K+ channel suppresses proliferation of microvascular and macrovascular endothelial cells and angiogenesis in vivo AU - Grgic, Ivica AU - Eichler, Ines AU - Heinau, Philipp AU - Si, Han AU - Brakemeier, Susanne AU - Hoyer, Joachim AU - Köhler, Ralf T2 - Arteriosclerosis, Thrombosis, and Vascular Biology AB - OBJECTIVE: Ca2+-activated K+ (K(Ca)) channels have been proposed to promote mitogenesis in several cell types. Here, we tested whether the intermediate-conductance K(Ca) channel (IKCa1) and the large-conductance K(Ca) channel (BK(Ca)) contribute to endothelial cell (EC) proliferation and angiogenesis. MATERIAL AND RESULTS: Function and expression of IKCa1 and BK(Ca)/Slo were investigated by patch-clamp analysis and real-time RT-PCR in human umbilical vein ECs (HUVECs) and in dermal human microvascular ECs 1 (HMEC-1). HMEC-1 expressed IKCa1 and BK(Ca)/Slo, whereas HUVECs expressed IKCa1. A 48-hour exposure to basic fibroblast growth factor (bFGF) augmented IKCa1 current amplitudes and induced a 3-fold increase in IKCa1 mRNA expression in HUVECs and HMEC-1. Vascular endothelial growth factor (VEGF) was also effective in upregulating IKCa1. BK(Ca)/Slo expression and current amplitudes in HMEC-1 were not altered by bFGF. bFGF- and VEGF-induced EC proliferation was suppressed by charybdotoxin, clotrimazole, or the selective IKCa1 blocker 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34), whereas inhibition of BK(Ca)/Slo by iberiotoxin was ineffective. In the Matrigel plug assay in mice, administration of TRAM-34 for 2 weeks significantly suppressed angiogenesis by approximately 85%. CONCLUSIONS: bFGF and VEGF upregulate expression of IKCa1 in human ECs. This upregulation of IKCa1 seems to be required for mitogen-induced EC proliferation and angiogenesis in vivo. Selective IKCa1 blocker might be of therapeutic value to prevent tumor angiogenesis. DA - 2005/04// PY - 2005 DO - 10.1161/01.ATV.0000156399.12787.5c DP - PubMed VL - 25 IS - 4 SP - 704 EP - 709 J2 - Arterioscler Thromb Vasc Biol LA - eng SN - 1524-4636 L1 - https://www.ahajournals.org/doi/pdf/10.1161/01.ATV.0000156399.12787.5c L2 - http://www.ncbi.nlm.nih.gov/pubmed/15662023 KW - Cell Division KW - Cells, Cultured KW - Clotrimazole KW - Endothelium, Vascular KW - Gene Expression KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Large-Conductance Calcium-Activated Potassium Channels KW - Membrane Potentials KW - Microcirculation KW - Neovascularization, Physiologic KW - Potassium Channel Blockers KW - Potassium Channels, Calcium-Activated KW - Pyrazoles KW - RNA, Messenger KW - Umbilical Veins ER - TY - JOUR TI - Functional importance of Ca2+-activated K+ channels for lysophosphatidic acid-induced microglial migration AU - Schilling, Tom AU - Stock, Christian AU - Schwab, Albrecht AU - Eder, Claudia T2 - The European Journal of Neuroscience AB - Abstract Migration of microglial cells towards damaged tissue plays a key role in central nervous system regeneration under pathological conditions. Using time lapse video microscopy we show that lysophosphatidic acid (LPA) enhances chemokinetic migration of murine microglial cells. In the presence of 1 micro m LPA, the mean migration rate of microglial cells was increased 3.8-fold. In patch-clamp studies we demonstrate that LPA induces activation of a Ca(2+)-activated K(+) current. Microglial Ca(2+)-activated K(+) currents were abolished by either 50 nm charybdotoxin or 10 micro m clotrimazole. In contrast, 5 micro m paxilline did not have any significant effects on Ca(2+)-activated K(+) currents. The LPA-stimulated migration of microglial cells was inhibited by blockers of IKCa1 Ca(2+)-activated K(+) channels. The mean migration rate of LPA-stimulated cells was decreased by 61% in the presence of 50 nm charybdotoxin or by 51% during exposure to 10 micro m clotrimazole. Microglial migration was not inhibited by 5 micro m paxilline. It is concluded that IKCa1 Ca(2+)-activated K(+) channels are required for LPA-stimulated migration of microglial cells. DA - 2004/03// PY - 2004 DO - 10.1111/j.1460-9568.2004.03265.x DP - PubMed VL - 19 IS - 6 SP - 1469 EP - 1474 J2 - Eur J Neurosci LA - eng SN - 0953-816X L2 - http://www.ncbi.nlm.nih.gov/pubmed/15066143 KW - Animals KW - Cell Line KW - Cell Movement KW - Charybdotoxin KW - Clotrimazole KW - Drug Interactions KW - Electric Conductivity KW - Ethidium KW - Growth Inhibitors KW - Indoles KW - Lysophospholipids KW - Mice KW - Microglia KW - Patch-Clamp Techniques KW - Potassium Channel Blockers KW - Potassium Channels, Calcium-Activated KW - Reverse Transcriptase Polymerase Chain Reaction KW - RNA, Messenger KW - Time Factors ER - TY - JOUR TI - Role of Ca2+-activated K+ channels in human erythrocyte apoptosis AU - Lang, Philipp A. AU - Kaiser, Stefanie AU - Myssina, Swetlana AU - Wieder, Thomas AU - Lang, Florian AU - Huber, Stephan M. T2 - American Journal of Physiology. Cell Physiology AB - Exposure of erythrocytes to the Ca2+ ionophore ionomycin has recently been shown to induce cell shrinkage, cell membrane blebbing, and breakdown of phosphatidylserine asymmetry, all features typical of apoptosis of nucleated cells. Although breakdown of phosphatidylserine asymmetry is thought to result from activation of a Ca2+-sensitive scramblase, the mechanism and role of cell shrinkage have not been explored. The present study was performed to test whether ionomycin-induced activation of Ca2+-sensitive Gardos K+ channels and subsequent cell shrinkage participate in ionomycin-induced breakdown of phosphatidylserine asymmetry of human erythrocytes. According to on-cell patch-clamp experiments, ionomycin (1 microM) induces activation of inwardly rectifying K+-selective channels in the erythrocyte membrane. Fluorescence-activated cell sorter analysis reveals that ionomycin leads to a significant decrease of forward scatter, reflecting cell volume, an effect blunted by an increase of extracellular K+ concentration to 25 mM and exposure to the Gardos K+ channel blockers charybdotoxin (230 nM) and clotrimazole (5 microM). As reflected by annexin binding, breakdown of phosphatidylserine asymmetry is triggered by ionomycin, an effect again blunted, but not abolished, by an increase of extracellular K+ concentration and exposure to charybdotoxin (230 nM) and clotrimazole (5 microM). Similar to ionomycin, glucose depletion leads (within 55 h) to annexin binding of erythrocytes, an effect again partially reversed by an increase of extracellular K+ concentration and exposure to charybdotoxin. K-562 human erythroleukemia cells similarly respond to ionomycin with cell shrinkage and annexin binding, effects blunted by antisense, but not sense, oligonucleotides against the small-conductance Ca2+-activated K+ channel isoform hSK4 (KCNN4). The experiments disclose a novel functional role of Ca2+-sensitive K+ channels in erythrocytes, i.e., their participation in regulation of erythrocyte apoptosis. DA - 2003/12// PY - 2003 DO - 10.1152/ajpcell.00186.2003 DP - PubMed VL - 285 IS - 6 SP - C1553 EP - 1560 J2 - Am J Physiol Cell Physiol LA - eng SN - 0363-6143 L2 - http://www.ncbi.nlm.nih.gov/pubmed/14600080 KW - Annexins KW - Apoptosis KW - Calcium KW - Cells, Cultured KW - Erythrocytes KW - Flow Cytometry KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Ionomycin KW - Ionophores KW - K562 Cells KW - Oligodeoxyribonucleotides, Antisense KW - Patch-Clamp Techniques KW - Phosphatidylserines KW - Potassium KW - Potassium Channels KW - Potassium Channels, Calcium-Activated ER - TY - JOUR TI - IKCa1 activity is required for cell shrinkage, phosphatidylserine translocation and death in T lymphocyte apoptosis AU - Elliott, James I. AU - Higgins, Christopher F. T2 - EMBO Reports AB - Apoptotic cell volume decrease (AVD) and exposure of phosphatidylserine (PtdSer) at the cell surface are early events in apoptosis. However, the ion channels responsible for AVD, and their relationship to PtdSer translocation and cell death are poorly understood. Real-time analysis of calcium-induced apoptosis in lymphocytes and thymocytes showed that AVD occurs rapidly, and precedes PtdSer translocation. Blockers of the K+ channel IKCa1 completely inhibited AVD. Blockade of IKCa1, and hence AVD, also completely prevented PtdSer translocation and cell death. Thus, IKCa1-mediated AVD is the earliest-defined essential step in calcium-induced apoptosis, required for both PtdSer translocation and cell death. DA - 2003/02// PY - 2003 DO - 10.1038/sj.embor.embor722 DP - PubMed Central VL - 4 IS - 2 SP - 189 EP - 194 J2 - EMBO Rep SN - 1469-221X UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1315824/ Y2 - 2021/05/15/12:00:05 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1315824/pdf/4-embor722.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1315824/ ER - TY - JOUR TI - Physiological roles of the intermediate conductance, Ca2+-activated potassium channel Kcnn4 AU - Begenisich, Ted AU - Nakamoto, Tesuji AU - Ovitt, Catherine E. AU - Nehrke, Keith AU - Brugnara, Carlo AU - Alper, Seth L. AU - Melvin, James E. T2 - The Journal of Biological Chemistry AB - Three broad classes of Ca(2+)-activated potassium channels are defined by their respective single channel conductances, i.e. the small, intermediate, and large conductance channels, often termed the SK, IK, and BK channels, respectively. SK channels are likely encoded by three genes, Kcnn1-3, whereas IK and most BK channels are most likely products of the Kcnn4 and Slo (Kcnma1) genes, respectively. IK channels are prominently expressed in cells of the hematopoietic system and in organs involved in salt and fluid transport, including the colon, lung, and salivary glands. IK channels likely underlie the K(+) permeability in red blood cells that is associated with water loss, which is a contributing factor in the pathophysiology of sickle cell disease. IK channels are also involved in the activation of T lymphocytes. The fluid-secreting acinar cells of the parotid gland express both IK and BK channels, raising questions about their particular respective roles. To test the physiological roles of channels encoded by the Kcnn4 gene, we constructed a mouse deficient in its expression. Kcnn4 null mice were of normal appearance and fertility, their parotid acinar cells expressed no IK channels, and their red blood cells lost K(+) permeability. The volume regulation of T lymphocytes and erythrocytes was severely impaired in Kcnn4 null mice but was normal in parotid acinar cells. Despite the loss of IK channels, activated fluid secretion from parotid glands was normal. These results confirm that IK channels in red blood cells, T lymphocytes, and parotid acinar cells are indeed encoded by the Kcnn4 gene. The role of these channels in water movement and the subsequent volume changes in red blood cells and T lymphocytes is also confirmed. Surprisingly, Kcnn4 channels appear to play no required role in fluid secretion and regulatory volume decrease in the parotid gland. DA - 2004/11/12/ PY - 2004 DO - 10.1074/jbc.M409627200 DP - PubMed VL - 279 IS - 46 SP - 47681 EP - 47687 J2 - J Biol Chem LA - eng SN - 0021-9258 L1 - https://www.jbc.org/content/279/46/47681.full.pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/15347667 KW - Animals KW - Calcium KW - CD4-Positive T-Lymphocytes KW - Cell Size KW - Electrophysiology KW - Erythrocytes KW - Female KW - Gene Targeting KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Male KW - Mice KW - Mice, Inbred C57BL KW - Mice, Knockout KW - Parotid Gland KW - Potassium Channels, Calcium-Activated KW - Rubidium Radioisotopes KW - Saliva ER - TY - JOUR TI - Design of a potent and selective inhibitor of the intermediate-conductance Ca2+-activated K+ channel, IKCa1: A potential immunosuppressant AU - Wulff, Heike AU - Miller, Mark J. AU - Hänsel, Wolfram AU - Grissmer, Stephan AU - Cahalan, Michael D. AU - Chandy, K. George T2 - Proceedings of the National Academy of Sciences of the United States of America AB - The antimycotic clotrimazole, a potent inhibitor of the intermediate-conductance calcium-activated K+ channel, IKCa1, is in clinical trials for the treatment of sickle cell disease and diarrhea and is effective in ameliorating the symptoms of rheumatoid arthritis. However, inhibition of cytochrome P450 enzymes by clotrimazole limits its therapeutic value. We have used a rational design strategy to develop a clotrimazole analog that selectively inhibits IKCa1 without blocking cytochrome P450 enzymes. A screen of 83 triarylmethanes revealed the pharmacophore for channel block to be different from that required for cytochrome P450 inhibition. The “IKCa1-pharmacophore” consists of a (2-halogenophenyl)diphenylmethane moiety substituted by an unsubstituted polar π-electron-rich heterocycle (pyrazole or tetrazole) or a −C 000000000000 000000000000 111111111111 000000000000 111111111111 000000000000 111111111111 000000000000 000000000000 N group, whereas cytochrome P450 inhibition absolutely requires the imidazole ring. A series of pyrazoles, acetonitriles, and tetrazoles were synthesized and found to selectively block IKCa1. TRAM-34 (1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole) inhibits the cloned and the native IKCa1 channel in human T lymphocytes with a Kd of 20–25 nM and is 200- to 1,500-fold selective over other ion channels. Using TRAM-34, we show that blocking IKCa1 in human lymphocytes, in the absence of P450-inhibition, results in suppression of mitogen-stimulated [3H]thymidine incorporation of preactivated lymphocytes with EC50-values of 100 nM-1 μM depending on the donor. Combinations of TRAM-34 and cyclosporin A are more effective in suppressing lymphocyte mitogenesis than either compound alone. Our studies suggest that TRAM-34 and related compounds may hold therapeutic promise as immunosuppressants. DA - 2000/07/05/ PY - 2000 DP - PubMed Central VL - 97 IS - 14 SP - 8151 EP - 8156 J2 - Proc Natl Acad Sci U S A SN - 0027-8424 ST - Design of a potent and selective inhibitor of the intermediate-conductance Ca2+-activated K+ channel, IKCa1 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC16685/ Y2 - 2021/05/15/12:32:36 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC16685/pdf/pq008151.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC16685/ ER - TY - JOUR TI - Therapy with oral clotrimazole induces inhibition of the Gardos channel and reduction of erythrocyte dehydration in patients with sickle cell disease. AU - Brugnara, C AU - Gee, B AU - Armsby, C C AU - Kurth, S AU - Sakamoto, M AU - Rifai, N AU - Alper, S L AU - Platt, O S T2 - Journal of Clinical Investigation AB - Pathologic water loss from sickle erythrocytes concentrates the abnormal hemoglobin and promotes sickling. The Ca2+-activated K+ channel (Gardos channel) contributes to this deleterious dehydration in vitro, and blockade of K+ and water loss via this channel could be a potential therapy in vivo. We treated five subjects who have sickle cell anemia with oral clotrimazole, a specific Gardos channel inhibitor. Patients were started on a dose of 10 mg clotrimazole/kg/d for one week. Protocol design allowed the daily dose to be escalated by 10 mg/kg each week until significant changes in erythrocyte density and K+ transport were achieved. Blood was sampled three times a week for hematological and chemical assays, erythrocyte density, cation content, and K+ transport. At dosages of 20 mg clotrimazole/kg/d, all subjects showed Gardos channel inhibition, reduced erythrocyte dehydration, increased cell K+ content, and somewhat increased hemoglobin levels. Adverse effects were limited to mild/moderate dysuria in all subjects, and a reversible increase in plasma alanine transaminase and aspartic transaminase levels in two subjects treated with 30 mg clotrimazole/kg/d. This is the first in vivo evidence that the Gardos channel causes dehydration of sickle erythrocytes, and that its pharmacologic inhibition provides a realistic antisickling strategy. DA - 1996/03/01/ PY - 1996 DP - PubMed Central VL - 97 IS - 5 SP - 1227 EP - 1234 J2 - J Clin Invest SN - 0021-9738 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC507175/ Y2 - 2021/05/15/12:52:58 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC507175/pdf/971227.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC507175/ ER - TY - ELEC TI - K+ channels as targets for specific immunomodulation UR - https://www-ncbi-nlm-nih-gov.ez.urosario.edu.co/pmc/articles/PMC2749963/ Y2 - 2021/05/15/12:53:21 L2 - https://www-ncbi-nlm-nih-gov.ez.urosario.edu.co/pmc/articles/PMC2749963/ ER - TY - JOUR TI - Microglial KCa3.1 Channels as a Potential Therapeutic Target for Alzheimer’s Disease AU - Maezawa, Izumi AU - Jenkins, David Paul AU - Jin, Benjamin E. AU - Wulff, Heike T2 - International Journal of Alzheimer’s Disease AB - There exists an urgent need for new target discovery to treat Alzheimer’s disease (AD); however, recent clinical trials based on anti-Aβ and anti-inflammatory strategies have yielded disappointing results. To expedite new drug discovery, we propose reposition targets which have been previously pursued by both industry and academia for indications other than AD. One such target is the calcium-activated potassium channel KCa3.1 (KCNN4), which in the brain is primarily expressed in microglia and is significantly upregulated when microglia are activated. We here review the existing evidence supporting that KCa3.1 inhibition could block microglial neurotoxicity without affecting their neuroprotective phagocytosis activity and without being broadly immunosuppressive. The anti-inflammatory and neuroprotective effects of KCa3.1 blockade would be suitable for treating AD as well as cerebrovascular and traumatic brain injuries, two well-known risk factors contributing to the dementia in AD patients presenting with mixed pathologies. Importantly, the pharmacokinetics and pharmacodynamics of several KCa3.1 blockers are well known, and a KCa3.1 blocker has been proven safe in clinical trials. It is therefore promising to reposition old or new KCa3.1 blockers for AD preclinical and clinical trials. DA - 2012/05/22/ PY - 2012 DO - 10.1155/2012/868972 DP - www.hindawi.com VL - 2012 SP - e868972 LA - en SN - 2090-8024 UR - https://www.hindawi.com/journals/ijad/2012/868972/ Y2 - 2021/05/15/20:24:08 L1 - https://downloads.hindawi.com/journals/ijad/2012/868972.pdf L2 - https://www.hindawi.com/journals/ijad/2012/868972/ ER - TY - JOUR TI - KCa3.1 Mediates Dysregulation of Mitochondrial Quality Control in Diabetic Kidney Disease AU - Huang, Chunling AU - Yi, Hao AU - Shi, Ying AU - Cao, Qinghua AU - Shi, Yin AU - Cheng, Delfine AU - Braet, Filip AU - Chen, Xin-Ming AU - Pollock, Carol A. T2 - Frontiers in Cell and Developmental Biology AB - Mitochondrial dysfunction is implicated in the pathogenesis of diabetic kidney disease. Mitochondrial quality control is primarily mediated by mitochondrial turnover and repair through mitochondrial fission/fusion and mitophagy. We have previously shown that blockade of the calcium-activated potassium channel KCa3.1 ameliorates diabetic renal fibrosis. However, the mechanistic link between KCa3.1 and mitochondrial quality control in diabetic kidney disease is not yet known. Transforming growth factor β1 (TGF-β1) plays a central role in diabetic kidney disease. Recent studies indicate an emerging role of TGF-β1 in the regulation of mitochondrial function. However, the molecular mechanism mediating mitochondrial quality control in response to TGF-β1 remains limited. In this study, mitochondrial function was assessed in TGF-β1-exposed renal proximal tubular epithelial cells (HK2 cells) transfected with scrambled siRNA or KCa3.1 siRNA. In vivo, diabetes was induced in KCa3.1+/+ and KCa3.1-/- mice by low-dose streptozotocin (STZ) injection. Mitochondrial fission/fusion-related proteins and mitophagy markers, as well as BCL2 interacting protein 3 (BNIP3) (a mitophagy regulator) were examined in HK2 cells and diabetic mice kidneys. The in vitro results showed that TGF-β1 significantly inhibited mitochondrial ATP production rate and increased mitochondrial ROS (mtROS) production when compared to control, which was normalized by KCa3.1 gene silencing. Increased fission and suppressed fusion were found in both TGF-β1-treated HK2 cells and diabetic mice, which were reversed by KCa3.1 deficiency. Furthermore, our results showed that mitophagy was inhibited in both in vitro and in vivo models of diabetic kidney disease. KCa3.1 deficiency restored abnormal mitophagy by inhibiting BNIP3 expression in TGF-β1-induced HK2 cells as well as in the diabetic mice. Collectively, these results indicate that KCa3.1 mediates the dysregulation of mitochondrial quality control in diabetic kidney disease. DA - 2021/// PY - 2021 DO - 10.3389/fcell.2021.573814 DP - PubMed VL - 9 SP - 573814 J2 - Front Cell Dev Biol LA - eng SN - 2296-634X L1 - https://www.frontiersin.org/articles/10.3389/fcell.2021.573814/pdf L2 - http://www.ncbi.nlm.nih.gov/pubmed/33681190 KW - diabetic kidney disease KW - KCa3.1 KW - mitochondrial dynamics KW - mitochondrial quality control KW - mitophagy KW - transforming growth factor β1 ER - TY - JOUR TI - Critical regulation of atherosclerosis by the KCa3.1 channel and the retargeting of this therapeutic target in in-stent neoatherosclerosis AU - Zhu, Yan-Rong AU - Jiang, Xiao-Xin AU - Zhang, Dai-Min T2 - Journal of Molecular Medicine AB - Coronary heart disease is a serious cardiovascular illness. Percutaneous coronary artery stent implantation has become a routine way to treat coronary heart disease. Although studies have shown how a drug-eluting stent could improve the efficacy of clinical treatment, 10~20% of in-stent restenosis is still an important outcome that restricts the clinical efficacy of drug-eluting stent implantations and causes cardiovascular events such as angina pectoris, acute myocardial infarction, and sudden death. The KCa3.1 channel plays an important role in neoatherosclerosis of in-stent restenosis by regulating macrophage function. Recent studies have shown that the KCa3.1 channel, which belongs to the family of calcium-activated potassium channels, plays an important role in the occurrence and development of various inflammatory diseases by regulating cell membrane potentials and calcium signaling in the processes of macrophage migration and mitogen-stimulated vascular smooth muscle cell and fibroblast proliferation. The KCa3.1 channel is activated by elevated intracellular calcium levels. Inhibition of the KCa3.1 channel can effectively slow the progression of arterial plaque rupture and reduce the degree of vascular restenosis, and so substances that can carry out this inhibition are expected to become targeted drugs for the treatment of in-stent neoatherosclerosis. This article reviews the pathological and physiological roles of the KCa3.1 channel and its roles in the disease prognosis of in-stent neoatherosclerosis. DA - 2019/09/01/ PY - 2019 DO - 10.1007/s00109-019-01814-9 DP - Springer Link VL - 97 IS - 9 SP - 1219 EP - 1229 J2 - J Mol Med LA - en SN - 1432-1440 UR - https://doi.org/10.1007/s00109-019-01814-9 Y2 - 2021/05/15/23:21:13 L1 - http://link.springer.com/content/pdf/10.1007%2Fs00109-019-01814-9.pdf ER - TY - JOUR TI - Role of KCa3.1 channels in proliferation and migration of vascular smooth muscle cells by diabetic rat serum AU - Su, Xing-Li AU - Zhang, Hong AU - Yu, Wei AU - Wang, Shuang AU - Zhu, Wei-Jun T2 - The Chinese Journal of Physiology AB - Proliferation and migration of vascular smooth muscle cells (VSMCs) are important events in the development of diabetic atherosclerosis. Previous studies have suggested that K(Ca)3.1 channels participate in atherosclerosis and coronary artery restenosis. In the present study, we attempted to clarify the roles of K(Ca)3.1 channels in the proliferation and migration of VSMCs using experimental type-2 diabetes rat serum and aortic smooth muscle cells (SMC) prepared from non-diabetic rats. mRNA and protein levels and current density of K(Ca)3.1 channels were greatly enhanced in cultured VSMCs treated with diabetic serum. In addition, diabetic serum promoted cell proliferation and migration in cultured VSMCs, and the effects were fully reversed in the cells treated with the K(Ca)3.1 channels blocker TRAM-34. In conclusion, serum from diabetic rats increases the expression of K(Ca)3.1 channels and promotes proliferation and migration of VSMCs to possibly participate in vascular remodeling in diabetes. DA - 2013/06/30/ PY - 2013 DO - 10.4077/CJP.2013.BAB104 DP - PubMed VL - 56 IS - 3 SP - 155 EP - 162 J2 - Chin J Physiol LA - eng SN - 0304-4920 L2 - http://www.ncbi.nlm.nih.gov/pubmed/23656217 KW - Animals KW - Atherosclerosis KW - Cell Movement KW - Cell Proliferation KW - Cells, Cultured KW - Diabetes Mellitus, Experimental KW - Diabetic Angiopathies KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Male KW - Muscle, Smooth, Vascular KW - Myocytes, Smooth Muscle KW - Random Allocation KW - Rats KW - Rats, Sprague-Dawley KW - Serum ER - TY - JOUR TI - Modulation of endothelial SK3 channel activity by Ca2+-dependent caveolar trafficking AU - Lin, Mike T. AU - Adelman, John P. AU - Maylie, James T2 - American Journal of Physiology-Cell Physiology AB - Small- and intermediate-conductance Ca2+-activated K+ channels (SK3/Kcnn3 and IK1/Kcnn4) are expressed in vascular endothelium. Their activities play important roles in regulating vascular tone through their modulation of intracellular concentration ([Ca2+]i) required for the production of endothelium-derived vasoactive agents. Activation of endothelial IK1 or SK3 channels hyperpolarizes endothelial cell membrane potential, increases Ca2+ influx, and leads to the release of vasoactive factors, thereby impacting blood pressure. To examine the distinct roles of IK1 and SK3 channels, we used electrophysiological recordings to investigate IK1 and SK3 channel trafficking in acutely dissociated endothelial cells from mouse aorta. The results show that SK3 channels undergo Ca2+-dependent cycling between the plasma membrane and intracellular organelles; disrupting Ca2+-dependent endothelial caveolae cycling abolishes SK3 channel trafficking. Moreover, transmitter-induced changes in SK3 channel activity and surface expression modulate endothelial membrane potential. In contrast, IK1 channels do not undergo rapid trafficking and their activity remains unchanged when either exo- or endocytosis is block. Thus modulation of SK3 surface expression may play an important role in regulating endothelial membrane potential in a Ca2+-dependent manner. DA - 2012/05/23/ PY - 2012 DO - 10.1152/ajpcell.00058.2012 DP - journals.physiology.org (Atypon) VL - 303 IS - 3 SP - C318 EP - C327 J2 - American Journal of Physiology-Cell Physiology SN - 0363-6143 UR - https://journals.physiology.org/doi/full/10.1152/ajpcell.00058.2012 Y2 - 2021/05/16/01:56:16 L1 - https://journals.physiology.org/doi/pdf/10.1152/ajpcell.00058.2012?rfr_dat=cr_pub++0pubmed&url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org L2 - https://journals.physiology.org/doi/full/10.1152/ajpcell.00058.2012?rfr_dat=cr_pub++0pubmed&url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org ER - TY - JOUR TI - The intermediate conductance Ca2+-activated K+ channel inhibitor TRAM-34 stimulates proliferation of breast cancer cells via activation of oestrogen receptors AU - Roy, J. W. AU - Cowley, E. A. AU - Blay, J. AU - Linsdell, P. T2 - British Journal of Pharmacology AB - BACKGROUND AND PURPOSE: K(+) channels play a role in the proliferation of cancer cells. We have investigated the effects of specific K(+) channel inhibitors on basal and oestrogen-stimulated proliferation of breast cancer cells. EXPERIMENTAL APPROACH: Using the mammary adenocarcinoma cell line MCF-7 we assayed cell proliferation by radiolabelled thymidine incorporation in the absence or presence of various K(+) channel inhibitors with or without 17beta-oestradiol. KEY RESULTS: Inhibitors of K(v)10.1 and K(Ca)3.1 K(+) channels suppressed basal proliferation of MCF-7 cells, but not oestrogen-stimulated proliferation. TRAM-34, a specific inhibitor of K(Ca)3.1 channels increased or decreased cell proliferation depending on the concentration. At intermediate concentrations (3-10 microM) TRAM-34 increased cell proliferation, whereas at higher concentrations (20-100 microM) TRAM-34 decreased cell proliferation. The enhancement of cell proliferation caused by TRAM-34 was blocked by the oestrogen receptor antagonists ICI182,780 and tamoxifen. TRAM-34 also increased progesterone receptor mRNA expression, decreased oestrogen receptor-alpha mRNA expression and reduced the binding of radiolabelled oestrogen to MCF-7 oestrogen receptor, in each case mimicking the effects of 17beta-oestradiol. CONCLUSIONS AND IMPLICATIONS: Our results demonstrate that K(+) channels K(v)10.1 and K(Ca)3.1 play a role in basal, but not oestrogen-stimulated MCF-7 cell proliferation. TRAM-34, as well as inhibiting K(Ca)3.1, directly interacts with the oestrogen receptor and mimics the effects of 17beta-oestradiol on MCF-7 cell proliferation and gene modulation. Our finding that TRAM-34 is able to activate the oestrogen receptor suggests a novel action of this supposedly specific K(+) channel inhibitor and raises concerns of interpretation in its use. DA - 2010/02/01/ PY - 2010 DO - 10.1111/j.1476-5381.2009.00557.x DP - PubMed VL - 159 IS - 3 SP - 650 EP - 658 J2 - Br J Pharmacol LA - eng SN - 1476-5381 L1 - https://europepmc.org/articles/pmc2828028?pdf=render L2 - http://www.ncbi.nlm.nih.gov/pubmed/20050851 KW - Breast Neoplasms KW - Calcium KW - Cell Line, Tumor KW - Cells KW - Cellular Structures KW - Estradiol KW - Estrogen Receptor alpha KW - Estrogens KW - Female KW - Gene Expression KW - Humans KW - Ion Transport KW - Potassium Channels, Calcium-Activated KW - Pyrazoles KW - Receptors, Estrogen KW - Receptors, Progesterone KW - RNA, Messenger KW - Tamoxifen ER - TY - ELEC TI - 1-EBIO | #E-150 | CAS 10045-45-1 T2 - Alomone Labs AB - High purity 1-EBIO (#E-150) (CAS 10045-45-1) is a potent KCa3.1 and KCa2 channel activator from Alomone Labs. A synthetic and biologically active compound. New lots are biologically tested. Free samples available. Lyophilized powder. Worldwide shipping at room temp. Top supplier for Ca2+-activated K+ channel research! LA - en-US UR - https://www.alomone.com/p/1-ebio/E-150 Y2 - 2021/05/16/16:54:34 L2 - https://www.alomone.com/p/1-ebio/E-150 ER - TY - JOUR TI - Endothelium-Dependent Vasodilation in Human Mesenteric Artery Is Primarily Mediated by Myoendothelial Gap Junctions Intermediate Conductance Calcium-Activated K+ Channel and Nitric Oxide AU - Chadha, Preet S. AU - Liu, Lu AU - Rikard-Bell, Matt AU - Senadheera, Sevvandi AU - Howitt, Lauren AU - Bertrand, Rebecca L. AU - Grayson, T. Hilton AU - Murphy, Timothy V. AU - Sandow, Shaun L. T2 - Journal of Pharmacology and Experimental Therapeutics AB - Myoendothelial microdomain signaling via localized calcium-activated potassium channel (KCa) and gap junction connexins (Cx) is critical for endothelium-dependent vasodilation in rat mesenteric artery. The present study determines the relative contribution of NO and gap junction-KCa mediated microdomain signaling to endothelium-dependent vasodilation in human mesenteric artery. The hypothesis tested was that such activity is due to NO and localized KCa and Cx activity. In mesenteric arteries from intestinal surgery patients, endothelium-dependent vasodilation was characterized using pressure myography with pharmacological intervention. Vessel morphology was examined using immunohistochemical and ultrastructural techniques. In vessel segments at 80 mm Hg, the intermediate (I)KCa blocker 1-[(2-chlorophenyl)diphenyl-methyl]-1H-pyrazole (TRAM-34; 1 μM) inhibited bradykinin (0.1 nM–3 μM)-induced vasodilation, whereas the small (S) KCa blocker apamin (50 and 100 nM) had no effect. Direct IKCa activation with 1-ethyl-2-benzimidazolinone (1-EBIO; 10–300 μM) induced vasodilation, whereas cyclohexyl-[2-(3,5-dimethyl-pyrazol-1-yl)-6-methyl-pyrimidin-4-yl]-amine (1–30 μM), the SKCa activator, failed to dilate arteries, whereas dilation induced by 1-EBIO (10–100 μM) was blocked by TRAM-34. Bradykinin-mediated vasodilation was attenuated by putative gap junction block with carbenoxolone (100 μM), with remaining dilation blocked by N-nitro l-arginine methyl ester (100 μM) and [1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one] (10 μM), NO synthase and soluble guanylate cyclase blockers, respectively. In human mesenteric artery, myoendothelial gap junction and IKCa activity are consistent with Cx37 and IKCa microdomain expression and distribution. Data suggest that endothelium-dependent vasodilation is primarily mediated by NO, IKCa, and gap junction Cx37 in this vessel. Myoendothelial microdomain signaling sites are present in human mesenteric artery and are likely to contribute to endothelium-dependent vasodilation via a mechanism that is conserved between species. DA - 2011/03/01/ PY - 2011 DO - 10.1124/jpet.110.165795 DP - jpet.aspetjournals.org VL - 336 IS - 3 SP - 701 EP - 708 J2 - J Pharmacol Exp Ther LA - en SN - 0022-3565, 1521-0103 UR - https://jpet.aspetjournals.org/content/336/3/701 Y2 - 2021/05/16/21:16:58 L2 - http://www.ncbi.nlm.nih.gov/pubmed/21172909 L2 - https://jpet.aspetjournals.org/content/336/3/701.long ER - TY - JOUR TI - Age-dependent neuroprotective effect of an SK3 channel agonist on excitotoxity to dopaminergic neurons in organotypic culture AU - Maldonado, Oscar AU - Jenkins, Alexandra AU - Belalcazar, Helen M. AU - Hernandez-Cuervo, Helena AU - Hyman, Katelynn M. AU - Ladaga, Giannina AU - Padilla, Lucia AU - Erausquin, Gabriel A. de T2 - PLOS ONE AB - Background Small conductance, calcium-activated (SK3) potassium channels control the intrinsic excitability of dopaminergic neurons (DN) in the midbrain and modulate their susceptibility to toxic insults during development. Methods We evaluated the age-dependency of the neuroprotective effect of an SK3 agonist, 1-Ethyl-1,3-dihydro-2H-benzimidazol-2-one (1-EBIO), on Amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) excitotoxicity to DN in ventral mesencephalon (VM) organotypic cultures. Results Most tyrosine hydroxylase (TH)+ neurons were also SK3+; SK3+/TH- cells (DN+) were common at each developmental stage but more prominently at day in vitro (DIV) 8. Young DN+ neurons were small bipolar and fusiform, whereas mature ones were large and multipolar. Exposure of organotypic cultures to AMPA (100 μm, 16 h) had no effect on the survival of DN+ at DIV 8, but caused significant toxicity at DIV 15 (n = 15, p = 0.005) and DIV 22 (n = 15, p<0.001). These results indicate that susceptibility of DN to AMPA excitotoxicity is developmental stage-dependent in embryonic VM organotypic cultures. Immature DN+ (small, bipolar) were increased after AMPA (100 μm, 16 h) at DIV 8, at the expense of the number of differentiated (large, multipolar) DN+ (p = 0.039). This effect was larger at DIV 15 (p<<<0.0001) and at DIV 22 (p<<<0.0001). At DIV 8, 30 μM 1-EBIO resulted in a large increase in DN+. At DIV 15, AMPA toxicity was prevented by exposure to 30 μM, but not 100 μM 1-EBIO. At DIV 22, excitotoxicity was unaffected by 30 μM 1-EBIO, and partially reduced by 100 μM 1-EBIO. Conclusion The effects of the SK3 channel agonist 1-EBIO on the survival of SK3-expressing dopaminergic neurons were concentration-dependent and influenced by neuronal developmental stage. DA - 2020/07/23/undefined PY - 2020 DO - 10.1371/journal.pone.0223633 DP - PLoS Journals VL - 15 IS - 7 SP - e0223633 J2 - PLOS ONE LA - en SN - 1932-6203 UR - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0223633 Y2 - 2021/05/16/21:22:09 L1 - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0223633&type=printable L2 - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0223633 KW - Developmental neuroscience KW - Dopamine KW - Dopaminergics KW - Midbrain KW - Neuronal differentiation KW - Neurons KW - Neuroprotectives KW - Toxicity ER - TY - JOUR TI - Calcium and Small-Conductance Calcium-Activated Potassium Channels in Gonadotropin-Releasing Hormone Neurons before, during, and after Puberty AU - Spergel, Daniel J. T2 - Endocrinology AB - The pubertal increase in GnRH secretion resulting in sexual maturation and reproductive competence is a complex process involving kisspeptin stimulation of GnRH neurons and requiring Ca2+ and possibly other intracellular messengers. To determine whether the expression of Ca2+ channels, or small-conductance Ca2+ -activated K+ (SK) channels, whose activity reflects cytoplasmic free Ca2+ concentration, changes at puberty in GnRH neurons, Ca2+ and SK currents in GnRH neurons were recorded in brain slices of juvenile [postnatal day (P) 10–21], pubertal (P28–P42), and adult (≥ P56) male GnRH-green fluorescent protein transgenic mice using perforated-patch and whole-cell techniques. Ca2+ currents were inhibited by the Ca2+ channel blocker Cd2+ and showed marked heterogeneity but were on average similar in juvenile, pubertal, and adult GnRH neurons. SK currents, which were inhibited by the SK channel blocker apamin and enhanced by the SK and intermediate-conductance Ca2+ -activated K+ channel activator 1-ethyl-2-benzimidazolinone, were also on average similar in juvenile, pubertal, and adult GnRH neurons. These findings suggest that whereas Ca2+ and SK channels may participate in the pubertal increase in GnRH secretion and there may be changes in Ca2+ or SK channel subtypes, overall Ca2+ and SK channel expression in GnRH neurons remains relatively constant across pubertal development. Hence, the expected increase in GnRH neuron cytoplasmic free Ca2+ concentration required for increased GnRH secretion at puberty appears to be due to mechanisms other than altered Ca2+ or SK channel expression, e.g. increased membrane depolarization and subsequent activation of pre-existing Ca2+ channels after increased excitatory synaptic input. DA - 2007/05// PY - 2007 DO - 10.1210/en.2006-1693 DP - PubMed Central VL - 148 IS - 5 SP - 2383 EP - 2390 J2 - Endocrinology SN - 0013-7227 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3315592/ Y2 - 2021/05/16/21:31:39 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3315592/pdf/nihms33101.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3315592/ ER - TY - JOUR TI - Evaluation of changes in corneal endothelium in chronic kidney disease AU - Kanawa, Surbhi AU - Jain, Kalpna AU - Sagar, Vinod AU - Yadav, Dinesh K. T2 - Indian Journal of Ophthalmology AB - Purpose:  Chronic kidney disease (CKD) is an emerging health problem worldwide. In CKD corneal endothelial changes also occur probably due to accumulation of inflammatory cytokines and increased multiple toxic products. The aim of this study was to analyze the effect of CKD on corneal endothelium and correlate the findings with severity of disease with help of noninvasive technique. Methods:  The study comprised 75 eyes of 75 cases divided into three groups with group A comprising of CKD cases on dialysis, group B of nondialysis CKD cases, and group C of controls. Each group had 25 cases each of either sex and between 15–80 age groups. All patients were investigated for blood urea, serum creatinine, and blood sugar and underwent complete ophthalmic examination of both eyes along with wide-field specular microscopy examination. Results:  The majority of patients (33.3%) belonged to age range of 61–70 years with male predominance and the most common cause of CKD was found to be diabetes with 17 (34%) cases. We found normal corneal endothelial cell density (ECD) with the mean ECD of 2364.52 ± 397.72 mm2 in the dialysis group, 2467.8 ± 352.88 mm2 in nondialysis group, and 2521.68 ± 250.26 mm2 in the control group of patients. However, we found significant increase in coefficient of variation (CV) with 36 ± 5.8% in dialysis group, 37 ± 4.5% in nondialysis group and 32 ± 0.8% in controls (P = 0.001) and decreased hexagonality (Hx) with 47 ± 7.3% in dialysis group, 46 ± 4.7% in nondialysis group and 51 ± 6.7% in the controls (P = 0.031). This showed increased tendency of pleomorphism and polymegathism in corneal endothelial cells in CKD cases. No correlation was found between blood urea or serum creatinine levels with endothelial parameters in any group. Conclusion:  CKD causes morphological changes like polymegathism and pleomorphism in corneal endothelium and hence these cases are more vulnerable and special care should be taken before any intraocular surgical procedure. DA - 2021/05// PY - 2021 DO - 10.4103/ijo.IJO_1764_20 DP - journals.lww.com VL - 69 IS - 5 SP - 1080 EP - 1083 LA - en-US SN - 0301-4738 UR - https://journals.lww.com/ijo/Fulltext/2021/05000/Evaluation_of_changes_in_corneal_endothelium_in.14.aspx Y2 - 2021/05/17/01:56:10 L2 - https://journals.lww.com/ijo/Fulltext/2021/05000/Evaluation_of_changes_in_corneal_endothelium_in.14.aspx ER - TY - JOUR TI - The Intermediate Conductance Calcium-activated Potassium Channel KCa3.1 Regulates Vascular Smooth Muscle Cell Proliferation via Controlling Calcium-dependent Signaling* AU - Bi, Dan AU - Toyama, Kazuyoshi AU - Lemaître, Vincent AU - Takai, Jun AU - Fan, Fan AU - Jenkins, David P. AU - Wulff, Heike AU - Gutterman, David D. AU - Park, Frank AU - Miura, Hiroto T2 - Journal of Biological Chemistry AB - The intermediate conductance calcium-activated potassium channel KCa3.1 contributes to a variety of cell activation processes in pathologies such as inflammation, carcinogenesis, and vascular remodeling. We examined the electrophysiological and transcriptional mechanisms by which KCa3.1 regulates vascular smooth muscle cell (VSMC) proliferation. Platelet-derived growth factor-BB (PDGF)-induced proliferation of human coronary artery VSMCs was attenuated by lowering intracellular Ca2+ concentration ([Ca2+]i) and was enhanced by elevating [Ca2+]i. KCa3.1 blockade or knockdown inhibited proliferation by suppressing the rise in [Ca2+]i and attenuating the expression of phosphorylated cAMP-response element-binding protein (CREB), c-Fos, and neuron-derived orphan receptor-1 (NOR-1). This antiproliferative effect was abolished by elevating [Ca2+]i. KCa3.1 overexpression induced VSMC proliferation, and potentiated PDGF-induced proliferation, by inducing CREB phosphorylation, c-Fos, and NOR-1. Pharmacological stimulation of KCa3.1 unexpectedly suppressed proliferation by abolishing the expression and activity of KCa3.1 and PDGF β-receptors and inhibiting the rise in [Ca2+]i. The stimulation also attenuated the levels of phosphorylated CREB, c-Fos, and cyclin expression. After KCa3.1 blockade, the characteristic round shape of VSMCs expressing high l-caldesmon and low calponin-1 (dedifferentiation state) was maintained, whereas KCa3.1 stimulation induced a spindle-shaped cellular appearance, with low l-caldesmon and high calponin-1. In conclusion, KCa3.1 plays an important role in VSMC proliferation via controlling Ca2+-dependent signaling pathways, and its modulation may therefore constitute a new therapeutic target for cell proliferative diseases such as atherosclerosis. Background: The mechanism by which KCa3.1 regulates cell proliferation remains elusive. Results: KCa3.1 regulates the expression of transcription factors and cyclins by controlling intracellular calcium levels in activated vascular smooth muscle cells (VSMCs). Conclusion: KCa3.1 is an important regulator of the calcium-dependent proliferation machinery in VSMCs. Significance: KCa3.1 modulation constitutes a therapeutic target for cell proliferative diseases such as atherosclerosis. DA - 2013/05/31/ PY - 2013 DO - 10.1074/jbc.M112.427187 DP - ScienceDirect VL - 288 IS - 22 SP - 15843 EP - 15853 J2 - Journal of Biological Chemistry LA - en SN - 0021-9258 UR - https://www.sciencedirect.com/science/article/pii/S002192582045971X Y2 - 2021/05/18/06:49:21 L1 - https://pdf.sciencedirectassets.com/778417/1-s2.0-S0021925820X63290/1-s2.0-S002192582045971X/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEL%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIGC1GL9kL5ULSckAXlijtQmMQrby5DOBgzEJUn32aCK6AiEA%2BvyMTT%2BXm6Jte0tL%2BUR6XPrzr8xRDt06kb6iOx7kE3oqtAMIVxADGgwwNTkwMDM1NDY4NjUiDOfJKUo%2Bjb%2FPhTgZTCqRA7tIkE8CjJlEJ50Svs3LvWW%2BZ4J7YdybVUrA7ClyOZTTHq2%2B8WFy2DBNFp%2BX%2BWN7KFWElEyXp5HTclp9p2t00W0KCY1Hdl3TXTcbDwYuBdASg1%2FUkszEQhhlScp4Y1tKJ9lzyUrz378pgY1gjnOGZqJQJX9Sm2nshAjFj%2FnRyK6MJrm6YjnfHXvICVtq4VJAJ0iZniIGoMs8%2B4grjlFjughMeupNzgHWz4xz%2BEbvbP3X9H7t%2B91yc2f0cm9DKuDkVDidfCdPA%2FyYCZns1tKIQJJitUB6ETbDpXxBOdC9LdyDXy0%2B7cqbDU1pTDcz6diGi0N58IbMrvfhQ8%2FtPc3zfkfnioAix6VBTsBk7IJ6zRsQ4yx7ZEKibwxeHzWx5uetzVKiHHv8SnAEO6KGHQSEULGdomKR67E%2FwbHftu%2F9c2nkBW0FruxkRLCOB53%2BY%2Bxd%2F9SYNuKFCIuDwRScscgEeTrnoYnLz4iXdEUi2FmnrV1aOkK2fRVlPviFYk%2F1j3uQNyfTysP5b9SfNoVIKqrtiyb%2BMP6yjYUGOusBBXXmXK%2FFU6xST9KoxWVUJLPVrxFiuMtTWmCL59VcSOuxV3DobFAO2J3ZmYT0%2BybmajaPUuFAH2fYHLoZypqDFfDoyQiwmmq97oCd0o7kjl561JUaqrSmcvQCQPEH99PxuVp51vFOrhu2xXAhUMPXT5DbOsLN2NVDjlGfICwFemkKARRYR0knNFx6UafwVE7pjQn9HSURFAcKKCTfMaO5qG6IFXSXHI0O7h7r4nrGyJ6wxwRDeGL8fEIJPc74ChTG8zZmHjbncmiRNqKn3k9q7UQPFWCubaTDtUmYUHx1zxfttDchDuDjU4afRw%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210518T064921Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY34EIMVOA%2F20210518%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=0cf7b320640f1c18d1a2337606be4767fde14e172359e8409f1199ff8ce1f28c&hash=ed56a4d36268634b01c389d6b1f1db60c9a4af754d40409ee682b453a74e31d3&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S002192582045971X&tid=spdf-8a835198-a386-4591-9de2-e9247d961027&sid=1f4e9f0e8b9376446b5adf718a187626a51dgxrqa&type=client L2 - http://www.sciencedirect.com/science/article/pii/S002192582045971X KW - Atherosclerosis KW - Calcium KW - Calcium Signaling KW - Cell Proliferation KW - Potassium Channels KW - Vascular Biology KW - Vascular Smooth Muscle Cells ER - TY - JOUR TI - Calcium and Vitamin D increase mRNA levels for the growth control hIK1 channel in human epidermal keratinocytes but functional channels are not observed AU - Manaves, Vlasios AU - Qin, Wuxuan AU - Bauer, Amy L. AU - Rossie, Sandra AU - Kobayashi, Masakazu AU - Rane, Stanley G. T2 - BMC Dermatology AB - Intermediate-conductance, calcium-activated potassium channels (IKs) modulate proliferation and differentiation in mesodermal cells by enhancing calcium influx, and they contribute to the physiology of fluid movement in certain epithelia. Previous reports suggest that IK channels stimulate proliferative growth in a keratinocyte cell line; however, because these channels indirectly promote calcium influx, a critically unique component of the keratinocyte differentiation program, an alternative hypothesis is that they would be anti-proliferative and pro-differentiating. This study addresses these hypotheses. DA - 2004/06/16/ PY - 2004 DO - 10.1186/1471-5945-4-7 DP - BioMed Central VL - 4 IS - 1 SP - 7 J2 - BMC Dermatology SN - 1471-5945 UR - https://doi.org/10.1186/1471-5945-4-7 Y2 - 2021/05/18/07:02:24 L1 - https://bmcdermatol.biomedcentral.com/track/pdf/10.1186/1471-5945-4-7 L2 - https://bmcdermatol.biomedcentral.com/articles/10.1186/1471-5945-4-7 KW - Human Keratinocyte Cell Line HaCaT KW - Human Skin Biopsy KW - Keratinocyte Differentiation KW - Patch Pipette Solution KW - Primary Human Keratinocytes ER - TY - JOUR TI - Intermediate conductance Ca2+-activated potassium channel (KCa3.1) in the inner mitochondrial membrane of human colon cancer cells AU - De Marchi, Umberto AU - Sassi, Nicola AU - Fioretti, Bernard AU - Catacuzzeno, Luigi AU - Cereghetti, Grazia M. AU - Szabò, Ildikò AU - Zoratti, Mario T2 - Cell Calcium AB - Patch-clamping mitoplasts isolated from human colon carcinoma 116 cells has allowed the identification and characterization of the intermediate conductance Ca(2+)-activated K(+)-selective channel K(Ca)3.1, previously studied only in the plasma membrane of various cell types. Its identity has been established by its biophysical and pharmacological properties. Its localisation in the inner membrane of mitochondria is indicated by Western blots of subcellular fractions, by recording of its activity in mitochondria made fluorescent by a mitochondria-targeted fluorescent protein and by the co-presence of channels considered to be markers of the inner membrane. Moderate increases of mitochondrial matrix [Ca(2+)] will cause mtK(Ca)3.1 opening, thus linking inner membrane K(+) permeability and transmembrane potential to Ca(2+) signalling. DA - 2009/05// PY - 2009 DO - 10.1016/j.ceca.2009.03.014 DP - PubMed VL - 45 IS - 5 SP - 509 EP - 516 J2 - Cell Calcium LA - eng SN - 1532-1991 L2 - http://www.ncbi.nlm.nih.gov/pubmed/19406468 KW - Animals KW - Calcium KW - Calcium Signaling KW - Cell Line, Tumor KW - Colonic Neoplasms KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Mitochondria KW - Mitochondrial Membranes KW - Patch-Clamp Techniques KW - Potassium ER - TY - JOUR TI - IK1 channel activity contributes to cisplatin sensitivity of human epidermoid cancer cells AU - Lee, Elbert L. AU - Hasegawa, Yuichi AU - Shimizu, Takahiro AU - Okada, Yasunobu T2 - American Journal of Physiology-Cell Physiology AB - Cisplatin, a platinum-based drug, is an important weapon against many types of cancer. It induces apoptosis by forming adducts with DNA, although many aspects of its mechanism of action remain to be clarified. Previously, we found a role for the volume-sensitive, outwardly rectifying Cl− channel in cisplatin-induced apoptosis. To investigate the possibility that cation channels also have a role in the cellular response to cisplatin, we examined the activity of cation channels in cisplatin-sensitive KB-3-1 (KB) epidermoid cancer cells by the whole cell patch-clamp method. A cation channel in KB cells, activated by hypotonic stress, was identified as the Ca2+-activated, intermediate-conductance K+ (IK1) channel on the basis of its requirement for intracellular Ca2+, its blockage by the blockers clotrimazole and triarylmethane-34, and its suppression by a dominant-negative construct. Activity of this channel was not observed in KCP-4 cells, a cisplatin-resistant cell line derived from KB cells, and its molecular expression, observed by semiquantitative RT-PCR and immunostaining, appeared much reduced. Cell volume measurements confirmed a physiological role for the IK1 channel as a component of the volume-regulatory machinery in KB cells. A possible role of the IK1 channel in cisplatin-induced apoptosis was investigated. It was found that clotrimazole and triarylmethane-34 inhibited a cisplatin-induced decrease in cell viability and increase in caspase-3/7 activity, whereas 1-ethyl-2-benzimidazolinone, an activator of the channel, had the opposite effect. Thus IK1 channel activity appears to mediate, at least in part, the response of KB cells to cisplatin treatment. DA - 2008/06/01/ PY - 2008 DO - 10.1152/ajpcell.00428.2007 DP - journals.physiology.org (Atypon) VL - 294 IS - 6 SP - C1398 EP - C1406 J2 - American Journal of Physiology-Cell Physiology SN - 0363-6143 UR - https://journals.physiology.org/doi/full/10.1152/ajpcell.00428.2007 Y2 - 2021/05/18/08:01:47 L1 - https://journals.physiology.org/doi/pdf/10.1152/ajpcell.00428.2007 L2 - https://journals.physiology.org/doi/full/10.1152/ajpcell.00428.2007 ER - TY - JOUR TI - Stimulation of corneal endothelial cell proliferation in vitro by fibroblast and epidermal growth factors AU - Gospodarowicz, Denis AU - Mescher, Anthony L. AU - Birdwell, Charles R. T2 - Experimental Eye Research AB - Bovine corneal endothelial cell culture has been developed to study the factors controlling corneal endothelium proliferation. Cells were prepared by scraping the posterior corneal surface gently with a grooved director. The endothelial segments were then suspended in DME with 10% calf serum and 100 ng/ml of fibroblast growth factor (FGF). After 4 days, corneal endothelial cells attached to the tissue culture dish, giving rise to colonies of small, rapidly dividing cells. Fixed cultures stained with silver nitrate to accentuate the inter-cellular function revealed the closely apposed nature of the polygonal cells within the monolayer, and the ovoid nucleus positioned eccentrically in each cell. This morphology is similar to that observed with the corneal endothelium in vivo. The ultrastructure of the bovine corneal endothelial cells grown in vitro was typical of cells with high metabolic rates. Cells had numerous mitochondria, polysomes and microfilament bundles. Ultrastructure and histochemical staining of the culture with alcian green demonstrated that the cells maintained in culture produced extracellular collagenous material. Both fibroblast growth factor (FGF) and epidermal growth factor (EGF) are mitogenic in vitro for endothelial cells derived from bovine corneas. Cells maintained at low density in the presence of 5% bovine plasma divided with a doubling time of 48 hr, but addition of either EGF or FGF reduced the cell doubling time to 20–24 hr. The final cell density reached in the presence of either growth factor was ten times that of cells maintained in 5% plasma alone. In the presence of 10% calf serum, corneal endothelial cells reached a final density identical to that obtained in 1% serum plus FGF and addition of FGF to 10% serum resulted in a final density three times higher than that observed with 10% serum alone. Inclusion of FGF in DME medium containing serum permitted cloning of corneal endothelial cells from cultures seeded at low density (0·6 cells/cm2). The half-maximal response for the stimulation of proliferation with EGF was seen at 1·5 × 10−10m and with FGF at 6 × 10−10m. Both EGF and FGF stimulated DNA synthesis in resting corneal endothelial cells, with EGF effective from 1·5 × 10−15 to 1·5 × 10−13m and FGF effective from 7 × 10−12 to 7 × 10−9m. Autoradiography demonstrated that FGF and EGF, like serum, stimulated the cell population as a whole to initiate DNA synthesis. DA - 1977/07/01/ PY - 1977 DO - 10.1016/0014-4835(77)90248-2 DP - ScienceDirect VL - 25 IS - 1 SP - 75 EP - 89 J2 - Experimental Eye Research LA - en SN - 0014-4835 UR - https://www.sciencedirect.com/science/article/pii/0014483577902482 Y2 - 2021/05/18/22:54:42 L2 - https://www.sciencedirect.com/science/article/abs/pii/0014483577902482 KW - corneal endothelium KW - EGF KW - growth control ER - TY - JOUR TI - Advanced glycation end products promote proliferation of cardiac fibroblasts by upregulation of KCa3.1 channels AU - Zhao, Li-Mei AU - Zhang, Wei AU - Wang, Li-Ping AU - Li, Gui-Rong AU - Deng, Xiu-Ling T2 - Pflügers Archiv - European Journal of Physiology AB - The present study was designed to investigate whether advanced glycation end products (AGEs) would regulate KCa3.1 channels in cardiac fibroblasts and participate in cell proliferation. Cultured adult rat cardiac fibroblasts were employed to investigate the regulation of KCa3.1 channels by advanced glycation end products–bovine serum albumin (AGE–BSA) and the role of KCa3.1 channels in cell proliferation using approaches of molecular biology. KCa3.1 channel mRNA and protein levels were greatly enhanced in cardiac fibroblasts treated with 200 μg/ml AGE–BSA, and the effects were countered by anti-RAGE antibody or the ERK1/2 inhibitor PD98059, the p38-MAPK inhibitor SB203580, and the PI3K/Akt inhibitor LY294002. In addition, AGE–BSA stimulated cell proliferation and collagen production in cultured cardiac fibroblasts, and the effects were reversed by KCa3.1 blocker TRAM-34, anti-RAGE antibody, or signal inhibitors PD98059, SB203580, and LY294002. These results demonstrate for the first time that AGEs increase the expression of KCa3.1 channels in a RAGE-dependent manner and promote cardiac fibroblast proliferation and collagen production, which is mediated by phosphorylation of ERK1/2, p38-MAPK, and PI3K/Akt signals. DA - 2012/12/01/ PY - 2012 DO - 10.1007/s00424-012-1165-0 DP - Springer Link VL - 464 IS - 6 SP - 613 EP - 621 J2 - Pflugers Arch - Eur J Physiol LA - en SN - 1432-2013 UR - https://doi.org/10.1007/s00424-012-1165-0 Y2 - 2021/05/18/23:20:56 L1 - http://link.springer.com/content/pdf/10.1007%2Fs00424-012-1165-0.pdf ER - TY - JOUR TI - Serum-activated K and Cl currents underlay U87-MG glioblastoma cell migration AU - Catacuzzeno, Luigi AU - Aiello, Francesco AU - Fioretti, Bernard AU - Sforna, Luigi AU - Castigli, Emilia AU - Ruggieri, Paola AU - Tata, Ada Maria AU - Calogero, Antonella AU - Franciolini, Fabio T2 - Journal of Cellular Physiology AB - Glioblastoma cells in vivo are exposed to a variety of promigratory signals, including undefined serum components that infiltrate into high grade gliomas as result of blood-brain barrier breakdown. Glioblastoma cell migration has been further shown to depend heavily on ion channels activity. We have then investigated the modulatory effects of fetal calf serum (FCS) on ion channels, and their involvement in U87-MG cells migration. Using the perforated patch-clamp technique we have found that, in a subpopulation of cells (42%), FCS induced: (1) an oscillatory activity of TRAM-34 sensitive, intermediate-conductance calcium-activated K (IK(Ca) ) channels, mediated by calcium oscillations previously shown to be induced by FCS in this cell line; (2) a stable activation of a DIDS- and NPPB-sensitive Cl current displaying an outward rectifying instantaneous current-voltage relationship and a slow, voltage-dependent inactivation. By contrast, in another subpopulation of cells (32%) FCS induced a single, transient IK(Ca) current activation, always accompanied by a stable activation of the Cl current. The remaining cells did not respond to FCS. In order to understand whether the FCS-induced ion channel activities are instrumental to promoting cell migration, we tested the effects of TRAM-34 and DIDS on the FCS-induced U87-MG cell migration using transwell migration assays. We found that these inhibitors were able to markedly reduce U87-MG cell migration in the presence of FCS, and that their co-application resulted in an almost complete arrest of migration. It is concluded that the modulation of K and Cl ion fluxes is essential for the FCS-induced glioblastoma cell migration. DA - 2011/07// PY - 2011 DO - 10.1002/jcp.22523 DP - PubMed VL - 226 IS - 7 SP - 1926 EP - 1933 J2 - J Cell Physiol LA - eng SN - 1097-4652 L2 - http://www.ncbi.nlm.nih.gov/pubmed/21506123 KW - 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid KW - Brain Neoplasms KW - Cell Line, Tumor KW - Cell Movement KW - Chloride Channels KW - Chlorides KW - Dose-Response Relationship, Drug KW - Glioblastoma KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Membrane Potentials KW - Neoplasm Invasiveness KW - Patch-Clamp Techniques KW - Potassium KW - Pyrazoles KW - Serum KW - Time Factors ER - TY - JOUR TI - Kinase activation of ClC-3 accelerates cytoplasmic condensation during mitotic cell rounding AU - Cuddapah, Vishnu Anand AU - Habela, Christa W. AU - Watkins, Stacey AU - Moore, Lindsay S. AU - Barclay, Tia-Tabitha C. AU - Sontheimer, Harald T2 - American Journal of Physiology. Cell Physiology AB - "Mitotic cell rounding" describes the rounding of mammalian cells before dividing into two daughter cells. This shape change requires coordinated cytoskeletal contraction and changes in osmotic pressure. While considerable research has been devoted to understanding mechanisms underlying cytoskeletal contraction, little is known about how osmotic gradients are involved in cell division. Here we describe cytoplasmic condensation preceding cell division, termed "premitotic condensation" (PMC), which involves cells extruding osmotically active Cl(-) via ClC-3, a voltage-gated channel/transporter. This leads to a decrease in cytoplasmic volume during mitotic cell rounding and cell division. Using a combination of time-lapse microscopy and biophysical measurements, we demonstrate that PMC involves the activation of ClC-3 by Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) in human glioma cells. Knockdown of endogenous ClC-3 protein expression eliminated CaMKII-dependent Cl(-) currents in dividing cells and impeded PMC. Thus, kinase-dependent changes in Cl(-) conductance contribute to an outward osmotic pressure in dividing cells, which facilitates cytoplasmic condensation preceding cell division. DA - 2012/02/01/ PY - 2012 DO - 10.1152/ajpcell.00248.2011 DP - PubMed VL - 302 IS - 3 SP - C527 EP - 538 J2 - Am J Physiol Cell Physiol LA - eng SN - 1522-1563 L2 - http://www.ncbi.nlm.nih.gov/pubmed/22049206 KW - Calcium-Calmodulin-Dependent Protein Kinase Type 2 KW - Cell Cycle KW - Cell Division KW - Cell Line, Tumor KW - Cell Membrane KW - Cell Proliferation KW - Cell Shape KW - Chloride Channels KW - Chlorides KW - Cytoskeleton KW - Gene Knockdown Techniques KW - Glioma KW - Humans KW - Mitosis KW - Osmotic Pressure KW - Patch-Clamp Techniques ER - TY - JOUR TI - Role of KCa3.1 Channels in Modulating Ca2+ Oscillations during Glioblastoma Cell Migration and Invasion AU - Catacuzzeno, Luigi AU - Franciolini, Fabio T2 - International Journal of Molecular Sciences AB - Cell migration and invasion in glioblastoma (GBM), the most lethal form of primary brain tumors, are critically dependent on Ca2+ signaling. Increases of [Ca2+]i in GBM cells often result from Ca2+ release from the endoplasmic reticulum (ER), promoted by a variety of agents present in the tumor microenvironment and able to activate the phospholipase C/inositol 1,4,5-trisphosphate PLC/IP3 pathway. The Ca2+ signaling is further strengthened by the Ca2+ influx from the extracellular space through Ca2+ release-activated Ca2+ (CRAC) currents sustained by Orai/STIM channels, meant to replenish the partially depleted ER. Notably, the elevated cytosolic [Ca2+]i activates the intermediate conductance Ca2+-activated K (KCa3.1) channels highly expressed in the plasma membrane of GBM cells, and the resulting K+ efflux hyperpolarizes the cell membrane. This translates to an enhancement of Ca2+ entry through Orai/STIM channels as a result of the increased electromotive (driving) force on Ca2+ influx, ending with the establishment of a recurrent cycle reinforcing the Ca2+ signal. Ca2+ signaling in migrating GBM cells often emerges in the form of intracellular Ca2+ oscillations, instrumental to promote key processes in the migratory cycle. This has suggested that KCa3.1 channels may promote GBM cell migration by inducing or modulating the shape of Ca2+ oscillations. In accordance, we recently built a theoretical model of Ca2+ oscillations incorporating the KCa3.1 channel-dependent dynamics of the membrane potential, and found that the KCa3.1 channel activity could significantly affect the IP3 driven Ca2+ oscillations. Here we review our new theoretical model of Ca2+ oscillations in GBM, upgraded in the light of better knowledge of the KCa3.1 channel kinetics and Ca2+ sensitivity, the dynamics of the Orai/STIM channel modulation, the migration and invasion mechanisms of GBM cells, and their regulation by Ca2+ signals. DA - 2018/10// PY - 2018 DO - 10.3390/ijms19102970 DP - www.mdpi.com VL - 19 IS - 10 SP - 2970 LA - en UR - https://www.mdpi.com/1422-0067/19/10/2970 Y2 - 2021/05/19/01:05:35 L1 - https://www.mdpi.com/1422-0067/19/10/2970/pdf L2 - https://www.mdpi.com/1422-0067/19/10/2970/htm KW - calcium oscillations KW - cell migration KW - glioblastoma KW - KCa3.1 channels KW - mathematical model ER - TY - JOUR TI - Calcium-activated K(+) channel (K(Ca)3.1) activity during Ca(2+) store depletion and store-operated Ca(2+) entry in human macrophages AU - Gao, Ya-dong AU - Hanley, Peter J. AU - Rinné, Susanne AU - Zuzarte, Marylou AU - Daut, Jurgen T2 - Cell Calcium AB - STIM1 'senses' decreases in endoplasmic reticular (ER) luminal Ca(2+) and induces store-operated Ca(2+) (SOC) entry through plasma membrane Orai channels. The Ca(2+)/calmodulin-activated K(+) channel K(Ca)3.1 (previously known as SK4) has been implicated as an 'amplifier' of the Ca(2+)-release activated Ca(2+) (CRAC) current, especially in T lymphocytes. We have previously shown that human macrophages express K(Ca)3.1, and here we used the whole-cell patch-clamp technique to investigate the activity of these channels during Ca(2+) store depletion and store-operated Ca(2+) influx. Using RT-PCR, we found that macrophages express the elementary CRAC channel components Orai1 and STIM1, as well as Orai2, Orai3 and STIM2, but not the putatively STIM1-activated channels TRPC1, TRPC3-7 or TRPV6. In whole-cell configuration, a robust Ca(2+)-induced outwardly rectifying K(+) current inhibited by clotrimazole and augmented by DC-EBIO could be detected, consistent with K(Ca)3.1 channel current (also known as intermediate-conductance IK1). Introduction of extracellular Ca(2+) following Ca(2+) store depletion via P2Y(2) receptors induced a robust charybdotoxin (CTX)- and 2-APB-sensitive outward K(+) current and hyperpolarization. We also found that SOC entry induced by thapsigargin treatment induced CTX-sensitive K(+) current in HEK293 cells transiently expressing K(Ca)3.1. Our data suggest that SOC and K(Ca)3.1 channels are tightly coupled, such that a small Ca(2+) influx current induces a much large K(Ca)3.1 channel current and hyperpolarization, providing the necessary electrochemical driving force for prolonged Ca(2+) signaling and store repletion. DA - 2010/07// PY - 2010 DO - 10.1016/j.ceca.2010.06.002 DP - PubMed VL - 48 IS - 1 SP - 19 EP - 27 J2 - Cell Calcium LA - eng SN - 1532-1991 L2 - http://www.ncbi.nlm.nih.gov/pubmed/20630587 KW - Calcium KW - Calcium Channels KW - Calcium Signaling KW - Cell Adhesion Molecules KW - Charybdotoxin KW - Clotrimazole KW - HEK293 Cells KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Macrophages KW - Membrane Proteins KW - Neoplasm Proteins KW - ORAI1 Protein KW - ORAI2 Protein KW - Patch-Clamp Techniques KW - Stromal Interaction Molecule 1 KW - Stromal Interaction Molecule 2 KW - Uridine Triphosphate ER - TY - JOUR TI - Histamine hyperpolarizes human glioblastoma cells by activating the intermediate-conductance Ca2+-activated K+ channel AU - Fioretti, Bernard AU - Catacuzzeno, Luigi AU - Sforna, Luigi AU - Aiello, Francesco AU - Pagani, Francesca AU - Ragozzino, Davide AU - Castigli, Emilia AU - Franciolini, Fabio T2 - American Journal of Physiology. Cell Physiology AB - The effects of histamine on the membrane potential and currents of human glioblastoma (GL-15) cells were investigated. In perforated whole cell configuration, short (3 s) applications of histamine (100 microM) hyperpolarized the membrane by activating a K(+)-selective current. The response involved the activation of the pyrilamine-sensitive H(1) receptor and Ca(2+) release from thapsigargin-sensitive intracellular stores. The histamine-activated current was insensitive to tetraethylammonium (3 mM), iberiotoxin (100 nM), and d-tubocurarine (100 microM) but was markedly inhibited by charybdotoxin (100 nM), clotrimazole (1 microM), and 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34, 1 microM), a pharmacological profile congruent with the intermediate conductance Ca(2+)-activated K(+) (IK(Ca)) channel. Cell-attached recordings confirmed that histamine activated a K(+) channel with properties congruent with the IK(Ca) channel (voltage independence, 22 pS unitary conductance and slight inward rectification in symmetrical 140 mM K(+)). More prolonged histamine applications (2-3 min) often evoked a sustained IK(Ca) channel activity, which depended on a La(2+) (10 microM)-sensitive Ca(2+) influx. Intracellular Ca(2+) measurements revealed that the sustained IK(Ca) channel activity enhanced the histamine-induced Ca(2+) signal, most likely by a hyperpolarization-induced increase in the driving force for Ca(2+) influx. In virtually all cells examined we also observed the expression of the large conductance Ca(2+)-activated K(+) (BK(Ca)) channel, with a unitary conductance of ca. 230 pS in symmetrical 140 mM K(+), and a Ca(2+) dissociation constant [K(D(Ca))] of ca. 3 microM, at -40 mV. Notably in no instance was the BK(Ca) channel activated by histamine under physiological conditions. The most parsimonious explanation based on the different K(D(Ca)) for the two K(Ca) channels is provided. DA - 2009/07// PY - 2009 DO - 10.1152/ajpcell.00354.2008 DP - PubMed VL - 297 IS - 1 SP - C102 EP - 110 J2 - Am J Physiol Cell Physiol LA - eng SN - 1522-1563 L1 - https://journals.physiology.org/doi/pdf/10.1152/ajpcell.00354.2008 L2 - http://www.ncbi.nlm.nih.gov/pubmed/19420000 KW - Brain Neoplasms KW - Calcium Signaling KW - Cell Line, Tumor KW - Glioblastoma KW - Histamine KW - Humans KW - Intermediate-Conductance Calcium-Activated Potassium Channels KW - Lanthanum KW - Membrane Potentials KW - Patch-Clamp Techniques KW - Potassium KW - Potassium Channel Blockers KW - Receptors, Histamine H1 KW - Time Factors ER - TY - JOUR TI - Development of a Cell-Based Assay for Identifying KCa3.1 Inhibitors Using Intestinal Epithelial Cell Lines AU - Jakakul, Chanon AU - Kanjanasirirat, Phongthon AU - Muanprasat, Chatchai T2 - SLAS DISCOVERY: Advancing the Science of Drug Discovery AB - Inhibition of the KCa3.1 potassium channel has therapeutic potential in a variety of human diseases, including inflammation-associated disorders and cancers. However, KCa3.1 inhibitors with high therapeutic promise are currently not available. This study aimed to establish a screening assay for identifying inhibitors of KCa3.1 in native cells and from library compounds derived from natural products in Thailand. The screening platform was successfully developed based on a thallium flux assay in intestinal epithelial (T84) cells with a Z′ factor of 0.52. The screening of 1352 compounds and functional validation using electrophysiological analyses identified 8 compounds as novel KCa3.1 inhibitors with IC50 values ranging from 0.14 to 6.57 µM. These results indicate that the assay developed is of excellent quality for high-throughput screening and capable of identifying KCa3.1 inhibitors. This assay may be useful in identifying novel KCa3.1 inhibitors that may have therapeutic potential for inflammation-associated disorders and cancers. DA - 2021/03/01/ PY - 2021 DO - 10.1177/2472555220950661 DP - SAGE Journals VL - 26 IS - 3 SP - 439 EP - 449 J2 - SLAS DISCOVERY: Advancing the Science of Drug Discovery LA - en SN - 2472-5552 UR - https://doi.org/10.1177/2472555220950661 Y2 - 2021/05/19/01:51:41 KW - assay development KW - high-throughput screening KW - KCa3.1 KW - natural compound KW - potassium channel ER - TY - JOUR TI - The Blockage of KCa3.1 Channel Inhibited Proliferation, Migration and Promoted Apoptosis of Human Hepatocellular Carcinoma Cells AU - Liu, Yu AU - Zhao, Liang AU - Ma, Wenya AU - Cao, Xuefeng AU - Chen, Hongyang AU - Feng, Dan AU - Liang, Jing AU - Yin, Kun AU - Jiang, Xiaofeng T2 - Journal of Cancer AB - The intermediate conductance calcium-activated potassium channel KCa3.1 plays an important role in regulating cell proliferation and migration. However, the role of KCa3.1 channel in human hepatocellular carcinoma remained unknown. This study was therefore performed to investigate the effects of KCa3.1 potassium channel blocker on the proliferation, apoptosis and migration of human hepatocellular cancer cells HepG2. KCa3.1 mRNA and protein were detected in HepG2. Furthermore, KCa3.1 potassium channel blocker TRAM-34 was capable to inhibit the proliferation and induce the apoptosis of HepG2 cells, which can be partially attenuated by 1-EBIO, an activator of KCa3.1 channel. Moreover, the migration of HepG2 was obviously inhibited by TRAM-34. Consistently, knockdown of KCa3.1 channel using its siRNA was also able to induce apoptosis and suppress proliferation and migration of HepG2. Meanwhile, intracellular ROS level was found augmented in HepG2 treated with TRAM-34. More importantly, p53 protein was found translocation from the cytoplasm into the nuclei of HepG2. Collectively, inhibition of KCa3.1 channel suppressed the growth and migration, and promoted the apoptosis of human hepatocellular carcinoma cells by regulating intracellular ROS level and promoting p53 activation. This data suggests TRAM-34 as a promising anti-tumor drug for liver cancer. DA - 2015/05/26/ PY - 2015 DO - 10.7150/jca.11913 DP - PubMed Central VL - 6 IS - 7 SP - 643 EP - 651 J2 - J Cancer SN - 1837-9664 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4466414/ Y2 - 2021/05/19/01:59:47 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4466414/pdf/jcav06p0643.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4466414/ ER - TY - JOUR TI - The anti-proliferative effect of cation channel blockers in T lymphocytes depends on the strength of mitogenic stimulation AU - Petho, Zoltan AU - Balajthy, Andras AU - Bartok, Adam AU - Bene, Krisztian AU - Somodi, Sandor AU - Szilagyi, Orsolya AU - Rajnavolgyi, Eva AU - Panyi, Gyorgy AU - Varga, Zoltan T2 - Immunology Letters AB - Ion channels are crucially important for the activation and proliferation of T lymphocytes, and thus, for the function of the immune system. Previous studies on the effects of channel blockers on T cell proliferation reported variable effectiveness due to differing experimental systems. Therefore our aim was to investigate how the strength of the mitogenic stimulation influences the efficiency of cation channel blockers in inhibiting activation, cytokine secretion and proliferation of T cells under standardized conditions. Human peripheral blood lymphocytes were activated via monoclonal antibodies targeting the TCR-CD3 complex and the co-stimulator CD28. We applied the blockers of Kv1.3 (Anuroctoxin), KCa3.1 (TRAM-34) and CRAC (2-Apb) channels of T cells either alone or in combination with rapamycin, the inhibitor of the mammalian target of rapamycin (mTOR). Five days after the stimulation ELISA and flow cytometric measurements were performed to determine IL-10 and IFN-γ secretion, cellular viability and proliferation. Our results showed that ion channel blockers and rapamycin inhibit IL-10 and IFN-γ secretion and cell division in a dose-dependent manner. Simultaneous application of the blockers for each channel along with rapamycin was the most effective, indicating synergy among the various activation pathways. Upon increasing the extent of mitogenic stimulation the anti-proliferative effect of the ion channel blockers diminished. This phenomenon may be important in understanding the fine-tuning of T cell activation. DA - 2016/03/01/ PY - 2016 DO - 10.1016/j.imlet.2016.02.003 DP - ScienceDirect VL - 171 SP - 60 EP - 69 J2 - Immunology Letters LA - en SN - 0165-2478 UR - https://www.sciencedirect.com/science/article/pii/S0165247816300128 Y2 - 2021/05/19/09:30:31 L1 - https://dea.lib.unideb.hu/dea/bitstream/handle/2437/222206/Immunol_letters_PethoZ.pdf?sequence=4&isAllowed=y L2 - https://www.sciencedirect.com/science/article/abs/pii/S0165247816300128 KW - Cellular proliferation KW - Cytokine secretion KW - Immune regulation KW - Ion channel KW - Rapamycin KW - T cells ER - TY - JOUR TI - The anti-proliferative effect of cation channel blockers in T lymphocytes depends on the strength of mitogenic stimulation AU - Petho, Zoltan AU - Balajthy, Andras AU - Bartok, Adam AU - Bene, Krisztian AU - Somodi, Sandor AU - Szilagyi, Orsolya AU - Rajnavolgyi, Eva AU - Panyi, Gyorgy AU - Varga, Zoltan T2 - Immunology Letters AB - Ion channels are crucially important for the activation and proliferation of T lymphocytes, and thus, for the function of the immune system. Previous studies on the effects of channel blockers on T cell proliferation reported variable effectiveness due to differing experimental systems. Therefore our aim was to investigate how the strength of the mitogenic stimulation influences the efficiency of cation channel blockers in inhibiting activation, cytokine secretion and proliferation of T cells under standardized conditions. Human peripheral blood lymphocytes were activated via monoclonal antibodies targeting the TCR-CD3 complex and the co-stimulator CD28. We applied the blockers of Kv1.3 (Anuroctoxin), KCa3.1 (TRAM-34) and CRAC (2-Apb) channels of T cells either alone or in combination with rapamycin, the inhibitor of the mammalian target of rapamycin (mTOR). Five days after the stimulation ELISA and flow cytometric measurements were performed to determine IL-10 and IFN-γ secretion, cellular viability and proliferation. Our results showed that ion channel blockers and rapamycin inhibit IL-10 and IFN-γ secretion and cell division in a dose-dependent manner. Simultaneous application of the blockers for each channel along with rapamycin was the most effective, indicating synergy among the various activation pathways. Upon increasing the extent of mitogenic stimulation the anti-proliferative effect of the ion channel blockers diminished. This phenomenon may be important in understanding the fine-tuning of T cell activation. DA - 2016/03/01/ PY - 2016 DO - 10.1016/j.imlet.2016.02.003 DP - ScienceDirect VL - 171 SP - 60 EP - 69 J2 - Immunology Letters LA - en SN - 0165-2478 UR - https://www.sciencedirect.com/science/article/pii/S0165247816300128 Y2 - 2021/05/19/09:48:32 L1 - https://pdf.sciencedirectassets.com/271143/1-s2.0-S0165247816X00028/1-s2.0-S0165247816300128/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjENn%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJGMEQCIGrNvIveKovZpYguY6jrWp1PdqR6bwmas9nPM9ou6rD1AiBFC5ESHzjoqcYqJJ6z85Yv6UOXl5yTvPVuEn6Gx7%2FBAiq0AwhyEAMaDDA1OTAwMzU0Njg2NSIMTpeLaozYsDE0DlTcKpEDz38nzFgmHhxb8fHznO61KLZ24dTbgyNlZXQWU%2FoT0HSsyNvRcC%2Fah6v4jrJJQV0HfWLSd6vsvk2HsZGZRibcJBWo4EUHbxLzjVDVykU51emsFHruSP2ft%2B%2B86PykH%2FWZuBMblNyPV9R0d3bv0zN4g3rqF83ak5Veb5Q0%2FTXkxFI7SuGQEl6E1IGWQlt1UEh4h1Li0BCIC54LS699cZYswxJXy4ObW3s0Hq40Kdojt2Vdpu8X5PEhJpvywVVStNskHgfYGAqoaWJTQLIbEkrL5qo9qf0pm9ChRBagGto5p5H8A33QqroeapA678NONN6CIMhFVr4iQ4NrhdNKUn9bkb7HC2GNvg8%2FNeZY9mObcYh5FtaCgdsO9Ke5vaRPmTjNpMIKpF5Tjzgo30%2FDpSu7IND%2BS9BURUogwb7YV8PB6Q7n%2FomTDyAL9kQbfWGnFZSMMPRx2OgRbnrA9kJq2O1KPI8BFwvlRQIJsBsK2M3nYVips80mPPr%2F2Cwh4xYXq4OWP7nUJOktKaj8beStx6xbCoUw86KThQY67AEv2ar9KvFzwl8lxN0eyYm3H7CHH4K4ChU%2BZyX9tlFopcBWj9jhkaEmUo5oP7U2j3MYQOK6XYtl%2BOSwj9kWYI09SiR9z%2Fa7AJ4Ke1c3utUXnfxbHu03F3A1OORHkWmO92yhSN1PxigufTP5xdHD%2FWjOiryQ0%2FRBpx3Qgy9McoiFOgbFWz2R5XolDlXELXTJVi1%2FZjh84nUlf3%2BWPM5B4urvs7EliO4c8SrvR0HTp7C0sKCl%2FK8NVca%2FgvwRA32K%2BkDFlvt63QOLnJP2gJ%2FtuehjfIiimNTaACOxiWiirF56Tkatv2Adj76BAcuDsw%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20210519T094832Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY2U3GL3VH%2F20210519%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=c6b815f0a0bf942faf7937c589f2ea3684e94886c283d28481036d666deb20c2&hash=d07521ac5f4bd82c69a58ef7b67705d68244d92d2e7e5c96cd6ad9ca7acbf788&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0165247816300128&tid=spdf-76bd0b74-8377-45b8-8a6e-5c5175ed5a7d&sid=a521c29385b3b249824a891-fdddf62e6b07gxrqa&type=client L2 - http://www.sciencedirect.com/science/article/pii/S0165247816300128 KW - Cellular proliferation KW - Cytokine secretion KW - Immune regulation KW - Ion channel KW - Rapamycin KW - T cells ER - TY - JOUR TI - Myopia, corneal endothelial cell density and morphology in a Japanese population-based cross-sectional study: the JPHC-NEXT Eye Study AU - Aketa, Naohiko AU - Uchino, Miki AU - Kawashima, Motoko AU - Uchino, Yuichi AU - Yuki, Kenya AU - Ozawa, Yoko AU - Sasaki, Mariko AU - Yamagishi, Kazumasa AU - Sawada, Norie AU - Tsugane, Shoichiro AU - Tsubota, Kazuo AU - Iso, Hiroyasu T2 - Scientific Reports AB - This population-based cross-sectional study was performed to determine the mean corneal endothelial cell density (ECD), coefficient of variation (CV), and hexagonality (HEX), and their associations with myopia in Japanese adults living in Chikusei city. Of 7109 participants with available data, 5713 (2331 male and 3382 female) participants were eligible for analysis. After assessing the relationship between participant characteristics and spherical equivalent refraction (SER), the association of SER with the abnormal value of ECD (< 2000 cells/mm), CV (≥ 0.40), and HEX (≤ 50%) were determined using the logistic regression models adjusting for potential confounders (age, intraocular pressure, keratometric power, height, and antihypertensive drug use). In male participants, there was no statistically significant relationships between SER and endothelial parameters. In female participants, compared to emmetropia, SER ≤ − 6 D had significantly higher odds ratio (OR) of having the abnormal value of CV (OR = 2.07, 95% confidence interval [CI] 1.39–3.10) and HEX (OR = 2.04, 95% CI 1.29–3.23), adjusted for potential confounders, indicating that the high myopia was associated with the abnormal values of CV and HEX. Further adjustment for contact lenses wear partly attenuated these associations. Association between the SER and ECD was not detected. DA - 2021/03/18/ PY - 2021 DO - 10.1038/s41598-021-85617-4 DP - www.nature.com VL - 11 IS - 1 SP - 6366 LA - en SN - 2045-2322 ST - Myopia, corneal endothelial cell density and morphology in a Japanese population-based cross-sectional study UR - https://www.nature.com/articles/s41598-021-85617-4 Y2 - 2021/05/19/23:15:15 L1 - https://www.nature.com/articles/s41598-021-85617-4.pdf L2 - https://www.nature.com/articles/s41598-021-85617-4 ER - TY - JOUR TI - Caracterización del endotelio corneal en pacientes con indicación de cirugía de catarata AU - Cárdenas Díaz, Taimi AU - Corcho Arévalo, Yeni AU - Torres Ortega, Rosario AU - Capote Cabrera, Armando AU - Hernández López, Iván AU - Cruz Izquierdo, Dunia T2 - Revista Cubana de Oftalmología DA - 2013/04// PY - 2013 DP - SciELO VL - 26 IS - 1 SP - 39 EP - 47 SN - 0864-2176 UR - http://scielo.sld.cu/scielo.php?script=sci_abstract&pid=S0864-21762013000100005&lng=es&nrm=iso&tlng=es Y2 - 2021/05/19/23:15:47 L1 - http://scielo.sld.cu/pdf/oft/v26n1/oft05113.pdf ER - TY - JOUR TI - Ultraviolet A light induces DNA damage and estrogen-DNA adducts in Fuchs endothelial corneal dystrophy causing females to be more affected AU - Liu, Cailing AU - Miyajima, Taiga AU - Melangath, Geetha AU - Miyai, Takashi AU - Vasanth, Shivakumar AU - Deshpande, Neha AU - Kumar, Varun AU - Ong Tone, Stephan AU - Gupta, Reena AU - Zhu, Shan AU - Vojnovic, Dijana AU - Chen, Yuming AU - Rogan, Eleanor G. AU - Mondal, Bodhiswatta AU - Zahid, Muhammad AU - Jurkunas, Ula V. T2 - Proceedings of the National Academy of Sciences of the United States of America AB - FECD is a genetic and female-predominant disorder which is the leading cause of corneal transplantation worldwide. There are no pharmacologic treatments for FECD; thus, there is a significant unmet need to improve the understanding of female prevalence in FECD pathogenesis. Herein, we reveal a physiologically relevant mechanism of UVA light causing DNA damage and inducing FECD, where greater DNA damage correlates with more severe FECD phenotype in females. Importantly, the sex-dependent effect of UVA is driven by the activation of CYP1B1, an enzyme which converts estrogen into metabolites that cause DNA damage. This study demonstrates an in vivo FECD model based on CE susceptibility to oxidative stress; furthermore, an antioxidant, NAC, restores UVA-induced changes, providing a potential therapeutic target., Fuchs endothelial corneal dystrophy (FECD) is a leading cause of corneal endothelial (CE) degeneration resulting in impaired visual acuity. It is a genetically complex and age-related disorder, with higher incidence in females. In this study, we established a nongenetic FECD animal model based on the physiologic outcome of CE susceptibility to oxidative stress by demonstrating that corneal exposure to ultraviolet A (UVA) recapitulates the morphological and molecular changes of FECD. Targeted irradiation of mouse corneas with UVA induced reactive oxygen species (ROS) production in the aqueous humor, and caused greater CE cell loss, including loss of ZO-1 junctional contacts and corneal edema, in female than male mice, characteristic of late-onset FECD. UVA irradiation caused greater mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) damage in female mice, indicative of the sex-driven differential response of the CE to UVA, thus accounting for more severe phenotype in females. The sex-dependent effect of UVA was driven by the activation of estrogen-metabolizing enzyme CYP1B1 and formation of reactive estrogen metabolites and estrogen-DNA adducts in female but not male mice. Supplementation of N-acetylcysteine (NAC), a scavenger of reactive oxygen species (ROS), diminished the morphological and molecular changes induced by UVA in vivo. This study investigates the molecular mechanisms of environmental factors in FECD pathogenesis and demonstrates a strong link between UVA-induced estrogen metabolism and increased susceptibility of females for FECD development. DA - 2020/01/07/ PY - 2020 DO - 10.1073/pnas.1912546116 DP - PubMed Central VL - 117 IS - 1 SP - 573 EP - 583 J2 - Proc Natl Acad Sci U S A SN - 0027-8424 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6955350/ Y2 - 2021/05/19/23:16:20 L1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6955350/pdf/pnas.201912546.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6955350/ ER - TY - ELEC TI - R: The R Project for Statistical Computing UR - https://www.r-project.org/ Y2 - 2021/06/02/17:05:44 L2 - https://www.r-project.org/ ER - TY - JOUR TI - Corneal endothelial cell dysfunction: etiologies and management AU - Feizi, Sepehr T2 - Therapeutic Advances in Ophthalmology AB - A transparent cornea is essential for the formation of a clear image on the retina. The human cornea is arranged into well-organized layers, and each layer plays a significant role in maintaining the transparency and viability of the tissue. The endothelium has both barrier and pump functions, which are important for the maintenance of corneal clarity. Many etiologies, including Fuchs’ endothelial corneal dystrophy, surgical trauma, and congenital hereditary endothelial dystrophy, lead to endothelial cell dysfunction. The main treatment for corneal decompensation is replacement of the abnormal corneal layers with normal donor tissue. Nowadays, the trend is to perform selective endothelial keratoplasty, including Descemet stripping automated endothelial keratoplasty and Descemet’s membrane endothelial keratoplasty, to manage corneal endothelial dysfunction. This selective approach has several advantages over penetrating keratoplasty, including rapid recovery of visual acuity, less likelihood of graft rejection, and better patient satisfaction. However, the global limitation in the supply of donor corneas is becoming an increasing challenge, necessitating alternatives to reduce this demand. Consequently, in vitro expansion of human corneal endothelial cells is evolving as a sustainable choice. This method is intended to prepare corneal endothelial cells in vitro that can be transferred to the eye. Herein, we describe the etiologies and manifestations of human corneal endothelial cell dysfunction. We also summarize the available options for as well as recent developments in the management of corneal endothelial dysfunction. DA - 2018/12/07/ PY - 2018 DO - 10.1177/2515841418815802 DP - PubMed Central VL - 10 J2 - Ther Adv Ophthalmol SN - 2515-8414 ST - Corneal endothelial cell dysfunction UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6293368/ Y2 - 2021/06/02/19:50:34 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6293368/pdf/10.1177_2515841418815802.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6293368/ ER - TY - JOUR TI - Evaluation of Corneal Higher-Order Aberrations by Scheimpflug–Placido Topography in Patients with Different Refractive Errors: A Retrospective Observational Study AU - Anbar, Mohamed AU - Mohamed Mostafa, Engy AU - Elhawary, Ashraf Mostafa AU - Awny, Islam AU - Farouk, Mahmoud Mohamed AU - Mounir, Amr T2 - Journal of Ophthalmology AB - Purpose To report the characteristics of anterior and posterior corneal high-order aberrations in patients with different refractive errors. Setting This study was conducted at Sohag Refractive Center, Sohag, Egypt. Design This is a retrospective observational study. Methods This study evaluated 750 patients (750 eyes) who were seeking refractive surgery. The eyes were stratified into five groups (150 eyes/group) based on refractive error: mild-to-moderate myopia, high myopia, hyperopia, simple myopic astigmatism, and simple hypermetropic astigmatism. All patients were subjected to comprehensive ophthalmological examination including corneal topography and corneal aberrometry using the Scheimpflug–Placido topography (Sirius, CSO, Italy). Results Coma aberration was statistically significant when compared in all five groups (P=0.01). It was highest in the hypermetropia group (0.26 ± 0.12 μm) but lower in the moderate myopia, high myopia, myopic astigmatism, and hypermetropic astigmatism groups. Spherical aberration was lowest in the hypermetropia group and significantly different from that in the other groups. Trefoil was statistically insignificant when all groups were compared (P=0.062) but was highest in the myopic astigmatism group (0.24 ± 0.25 μm). Total RMS peaked in the hypermetropia group (0.99 ± 0.70). Conclusions In normal corneas and regular refractive errors, the cornea-induced high-order aberration was minimal, and all types of refractive errors were associated with certain types of high-order aberrations, with a significant increase in spherical aberration in the hypermetropia group. DA - 2019/06/02/ PY - 2019 DO - 10.1155/2019/5640356 DP - PubMed Central VL - 2019 J2 - J Ophthalmol SN - 2090-004X ST - Evaluation of Corneal Higher-Order Aberrations by Scheimpflug–Placido Topography in Patients with Different Refractive Errors UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6589193/ Y2 - 2021/06/02/21:52:31 L1 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6589193/pdf/JOPH2019-5640356.pdf L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6589193/ ER -