Abstract:AIM: To investigate the protective effect and mechanism of luteolin on H2O2-induced oxidative damage of retinal pigment epithelium(RPE)cells.
METHODS:ARPE-19 cells were divided into the control group, H2O2 group, different doses of luteolin groups and Nrf2 inhibitor group, and the oxidative damage model of RPE was prepared by 100μmol/L H2O2, except for the control group. Cell activity was detected by Methyl thiazolyl tetrazolium(MTT)assay and proper experimental concentration of luteolin was determined. The cell morphology and activity was observed in each group. Cell apoptosis rate and reactive oxygen species(ROS)were detected by flow cytometry, malondialdehyde(MDA)and superoxide dismutase(SOD)were detected by kit method, and the expression of caspase-3, poly adeno-sine diphosphate ribose polymerase(PARP), B cell lymphoma-2(Bcl-2), nuclear factor erythroid 2-related factor 2(Nrf2)and heme oxygenase-1(HO-1)proteins were detected by Western blot.
RESULTS: 100μmol/L luteolin has toxic effects on ARPE-19 cells, so 25μmol/L and 50μmol/L luteolin were selected for subsequent experiments. The cell activity, SOD activity and the protein expression levels of Bcl-2, Nrf2, HO-1 in 25μmol/L and 50μmol/L luteolin groups were significantly higher than the H2O2 group(P<0.05). The apoptosis rate, ROS, MDA content and the protein expression levels of Caspase-3 and PARP in 25μmol/L and 50μmol/L luteolin groups were significantly lower than the H2O2 group(P<0.05). The cell activity, SOD activity \〖(13.83±1.49)U/mL vs(22.69±1.83)U/mL\〗 and the protein expression levels of Bcl-2, Nrf2 and HO-1 protein expression in the Nrf2 inhibitor group were significantly lower than the 50μmol/L luteolin group(P<0.05). The apoptosis rate, ROS, MDA content \〖(654.96±26.99)vs(446.52±29.42),(3.89±0.29)nmol/mL vs(2.06±0.19)nmol/mL\〗 and the protein expression levels of Caspase-3 and PARP in the Nrf2 inhibitor group were significantly higher than the 50μmol/L luteolin group(P<0.05).
CONCLUSION: Luteolin can improve the oxidative damage of RPE cells induced by H2O2, and its mechanism may be related to the activation of the Nrf2/HO-1 pathway.
