Abstract:Establishment a reasonable and reliable oxidative stress model can offer theory basis for screening antioxidant components and revealing the oxidative stress mechanism.The present study was to establish an ox－idative stress model in HepG2 cells mediated by hydrogen peroxide （H2O2）.HepG2 cells were treated with different concentrations of H2O2for different time to establish the cell model.MTT assay was used to detect cell viability and DCFH-DA method was employed to evaluate the reactive oxygen species （ROS）level.The malondialdehyde spectrophotometry（MDA）content and the activities of superoxide dismutase（SOD），catalase（CAT），glutathione peroxidase（GSH-Px）were detected by spectrophotometry.The results showed that the cell viability of HepG2 cells decreased with the increasing of H2O2concentration and the lengthening of action time.Meanwhile，ROS level and MDA content increased and the activities of SOD，CAT and GSH-Px decreased.When treated with 200 μmol/L H2O2for 6 h，cell viability decreased significantly to 63.1%（P<0.05），ROS level and MDA content significantly increased to 127.1%and 135.1%，respectively（P<0.05），and the activities of SOD，CAT and GSH-Px significantly decreased to 77.28%，78.56%and 77.41%，respectively（P<0.05）compared with control group.It was concluded that the optimal H2O2concentration was 200 μmol/L，and the action time was 6 h，which were able to establish the oxidative stress model of HepG2 cells induced by H2O2.