Caspase-3 and its inhibitor Ac-DEVD-CHO in rat lens epithelial cell apoptosis induced by hydrogen in vitro.

OBJECTIVE: To investigate the role of caspase-3 and its inhibitor Ac-DEVD-CHO in rat lens epithelial cell apoptosis induced by hydrogen peroxide (H(2)O(2)) in vitro. METHODS: Rat lenses were incubated in modified Eagle's medium containing 2 mmol/L H(2)O(2) to induce apoptosis in vitro. Apoptosis in lens epithelial cells was assessed by transmission electron microscopy and annexin V-propidium iodide (PI) double staining flow cytometry after 12, 24 and 48 h of incubation. The activity of caspase-3 was analyzed by western blotting. RESULTS: Observations under transmission electron microscopy revealed that 2 mmol/L H(2)O(2) could effectively induce lens epithelial cell apoptosis in vitro. Caspase-3 activity increased during cell apoptosis and the peak measurement occurred at 24 h after treatment with H(2)O(2). Cell apoptosis was blocked by caspase-3 inhibitor Ac-DEVD-CHO. CONCLUSIONS: The activation of caspase-3 plays an important role in executing apoptosis in H(2)O(2)-treated lens epithelial cells and in the formation of cataract. The caspase-3 inhibitor Ac-DEVD-CHO may effectively prevent lens epithelial cell apoptosis caused by oxidative injury.