title: [The mechanism of accumulative oxidative injury by hydrogen peroxide on human retinal pigment epithelial cells].
abstract: OBJECTIVE
  To explore the effects of oxidative injury induced by hydrogen peroxide on human retinal pigment epithelial (RPE) cells.
  
  
  METHODS
  Cultured human RPE cells were treated by 600 micromol/L hydrogen peroxide (H2O2) for 1, 6, 12, 24 and 72 hours. Cell viability was assessed by the MTT assay. Apoptosis was assessed by Annexin V-fluorescein isothiocyanate/Propidium iodium (Annexin V-FITC/PI) staining. The expression of clusterin was assessed by Western blot.
  
  
  RESULTS
  (1) The treatment of RPE cells with 600 micromol/L H2O2 caused a time-dependent decrease of cellular viability. (2) Apoptosis was detected in cultured human RPE cells treated with 600 micromol/L H2O2 for 6 hours. The number of apoptotic cells reached a maximum at 24th hour after being exposed to 600 micromol/L H2O2 (P < 0.05). (3) Western blot showed the expression of clusterin protein was demonstrated in 6 hours exposure to 600 micromol/L H2O2, a significantly increasing of clusterin expression was observed overtime (P < 0.01). Thereafter the expression of clusterin protein decreased at 24th hour after being exposed to 600 micromol/L H2O2. At 72nd hour, the expression of clusterin protein was quite weak.
  
  
  CONCLUSIONS
  Hydrogen peroxide can inhibits RPE proliferation and induces apoptosis and aging gene expression;the result suggest that accumulative oxidative injury induced by hydrogen peroxide in RPE in vitro may be similar to the aging changes in vivo.
authors.affiliation: The Medical School Hospital of Qingdao University, Qingdao 266003, China. niuyingjun@yahoo.com.cn
authors.forename: Ying-jun
authors.initials: YJ
authors.lastname: Niu
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhao
authors.forename: Zhan-yu
authors.initials: ZY
authors.lastname: Zhou
authors.forename: Fu-ling
authors.initials: FL
authors.lastname: Liu
authors.forename: Cheng-gui
authors.initials: CG
authors.lastname: Liu
authors.forename: Yan-xia
authors.initials: YX
authors.lastname: Huang
mesh_terms: D017209:Apoptosis; D002478:Cells, Cultured; D051152:Clusterin / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D018384:Oxidative Stress; D010857:Pigment Epithelium of Eye / Q000378:metabolism / Q000473:pathology*
chemical_list: D051152:Clusterin; D006861:Hydrogen Peroxide