K Inoue1, S Kubota, T Tsuru, M Araie, Y Seyama. 1. Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, Japan.
Abstract
PURPOSE: To determine whether cholestanol induces cornea endothelial and lens epithelial cell death in vitro. METHODS: Cornea endothelial and lens epithelial cells were cultured in minimum essential media with 10% fetal bovine serum containing 10 microg/ml cholesterol in ethanol, 10 microg/ml cholestanol in ethanol, or 1% ethanol. These cells, stained using the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) method, were analyzed by laser cytometer. The activities of ICE and CPP32 proteases in cells were also measured. RESULTS: Both cornea endothelial and lens epithelial cells cultured with 10 microg/ml cholestanol showed a significant loss of viability. The nuclei of these cells cultured with 10 microg/ml cholestanol were more frequently stained than those exposed to 10 microg/ml cholesterol or 1% ethanol. Quantitative analysis of apoptotic DNA fragmentation confirmed that the cholestanol induced apoptosis of these cells in a time-dependent manner. The activities of interleukin-1beta-converting enzyme (ICE) and CPP32 proteases for cells cultured with 10 microg/ml cholestanol were significantly higher than those observed in control cells. CONCLUSIONS: In vitro, cholestanol was taken up by corneal endothelial cells and lens epithelial cells, an event that led to apoptosis of these cells.
PURPOSE: To determine whether cholestanol induces cornea endothelial and lens epithelial cell death in vitro. METHODS: Cornea endothelial and lens epithelial cells were cultured in minimum essential media with 10% fetal bovine serum containing 10 microg/ml cholesterol in ethanol, 10 microg/ml cholestanol in ethanol, or 1% ethanol. These cells, stained using the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) method, were analyzed by laser cytometer. The activities of ICE and CPP32 proteases in cells were also measured. RESULTS: Both cornea endothelial and lens epithelial cells cultured with 10 microg/ml cholestanol showed a significant loss of viability. The nuclei of these cells cultured with 10 microg/ml cholestanol were more frequently stained than those exposed to 10 microg/ml cholesterol or 1% ethanol. Quantitative analysis of apoptotic DNA fragmentation confirmed that the cholestanol induced apoptosis of these cells in a time-dependent manner. The activities of interleukin-1beta-converting enzyme (ICE) and CPP32 proteases for cells cultured with 10 microg/ml cholestanol were significantly higher than those observed in control cells. CONCLUSIONS: In vitro, cholestanol was taken up by corneal endothelial cells and lens epithelial cells, an event that led to apoptosis of these cells.