Change in apoptosis and its mechanism in intestinal epithelial cells under oxidative stress

Objective To investigate change in apoptosis level and its mechanism of intestinal epithelial cells under oxidative stress. Methods HT - 29 cells were cultured in vitro, which were treated with hydrogen peroxide(H2O2), to simulate the intestinal epithelial cells injured by reactive oxidative species. The cells viability was observed by 3 -(4, 5 - dimethylthiazol - 2 - yl)- 2, 5- diphenyltetrazolium bromide (MTT) assay. Moreover, cell apoptosis and apoptosis associated proteins were evaluated by flow cytometry and Western blot. Results Cells viability of HT - 29 was decreased by H2O2 which showed dose -dependent and time -dependent patterns (all P0. 05). The cell apoptotic ratios were increased with the concentration of H2O2 increased and the time of the stimulation prolonged compared with the controls (all P0. 05). Although the expression of the Bax was increased when HT - 29 cells were stimulated with different concentrations of H2O2 for 24 hours, the expression of Bcl - 2 was decreased. While HT - 29 cells were stimulated with 500 μmol/L H2O2, the expression of the Bax was increased and that of Bcl - 2 was decreased overtime. Conclusion These data suggest that oxidative stress appears to be related to the apoptosis in intestinal epithelial cells under stress. The imbalance of Bcl - 2/Bax expression might result in intestinal epithelial cell apoptosis in oxidative stress.