title: [Change in apoptosis and its mechanism in intestinal epithelial cells under oxidative stress].
abstract: 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 P<0.05). The cell apoptotic ratios were increased with the concentration of H2O2 increased and the time of the stimulation prolonged compared with the controls (all P<0.05). 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 micromol/L H2O2, the expression of the Bax was increased and that of Bcl-2 was decreased overtime.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Gastroenterological Surgery, People's Hospital of Peking University, Beijing 100044, China. zhoujing58@sohu.com
authors.forename: Jing
authors.initials: J
authors.lastname: Zhou
authors.forename: Shan
authors.initials: S
authors.lastname: Wang
authors.forename: Ying-jiang
authors.initials: YJ
authors.lastname: Ye
authors.forename: Shen
authors.initials: S
authors.lastname: Yang
authors.forename: Zhi-rong
authors.initials: ZR
authors.lastname: Cui
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D002470:Cell Survival / Q000187:drug effects; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology*; D019073:HT29 Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D006861:Hydrogen Peroxide