Expression of aquaporin-1 in human lens epithelial cells by hyperosmotic stimuli

Background Diabetic cataract is a severe blinding eye disease.It is the most common complication of diabetes.Aquaporin (AQP) plays an important role for maintaining the dehydration and transparency of lens epithelial cells.Objective The aim of this study was to investigate the role of AQP-1 in the pathogenesis of diabetic cataract.Methods Human lens epithelial cells (LECs) were isolated from the healthy donor eyes and were cultured in 1 g/L glucose+DMEM containing 150 mL/L fetal bovine serum(control group) or 4.5 g/L glucose+DMEM containing 150 mL/L fetal bovine serum (high glucose group) for 3 days or 28 days respectively.The expression of AQP-1 in human LECs was detected using immunofluorescence techniques and flow cytometry.The apoptosis and necrosis rates of LECs were detected using flow cytometry.This study was approved by the Ethic Committee of this hospital.Results The morphology of cultured LECs was similar in the third day in control group and high glucose group.However,the slender cells were obvious increased in high glucose group compared to control group.The mean fluorescence intensity of AQP-1 was enhanced in high glucose group in comparison with control group (t=3.934,P=0.004),but no significant differences were found in the apoptosis rate and necrosis rate between two groups (t=1.681,P=0.131;t=1.064,P=0.318) in the third day of culture.The expression of AQP-1 in the high glucose cultured group was stronger than that of the control group 3 days after hyperosmotic stimuli.The difference was significantly different(t=3.934,P=0.004).In 28 days after culture,the fluorescence intensity of AQP-1 was obviously weakened in high glucose group compared with control group (t=3.069,P=0.015),and the apoptosis rate and necrosis rate of LECs in high glucose group were higher than those of the control group (apoptosis rate:t=11.213,P0.01;necrosis rate:t=15.778,P0.01).Conclusion AQP-1 may play an important role in the pathogenesis of diabetic cataract.