AIM: To discuss the protective effects and possible mechanisms of quercetin in oxidative damage of human retina pigment epithelium(RPE)cells induced by H₂O₂.

METHODS: RPE cells were subculture, and they were divided into negative control group: cultured with normal culture medium; oxidative injury group: 100 μmol/L H₂O₂ treated for 12h; quercetin low dose group: 100 μmol/L quercetin incubated for 24h then treated with 100 μmol/L H₂O₂ for 12h; and quercetin high dose group: 100 μmol/L quercetin incubated for 24h then treated with 100 μmol/L H₂O₂ for 12h. Cell viability were tested by MTT colorimetric detection, apoptosis rate was detected by flow cytometry, apoptotic cell morphology was observed by Hochest33258 staining, expression of catalase(CAT), superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)were tested by colorimetric detection.

RESULTS: Quercetin inhibited H₂O₂-induced cell viability decreased in RPE cells, after treated with different concentrations of quercetin, RPE cells activity increased to(79.67±4.98)% and(83.00±3.60)%, which had statistical significance difference compared with oxidative damage group(48.93±3.39)%(P<0.05). After treated with different concentrations of quercetin, the apoptosis rate of RPE cells decreased to(23.23±3.29)% and(16.23±1.94)%, respectively, which had statistical significance difference compared with oxidative damage group(38.03±4.76)%(P<0.05). In addition, quercetin also increased the expression of CAT、SOD、GSH-Px in RPE cells, which had statistical significance difference compared with oxidative damage group.

CONCLUSION:Quercetin effectively inhibited H₂O₂-induced RPE cells damage by improving cell antioxidant enzyme activity, which provide reliable experimental basis for the treatment of injuries in RPE cells.