Ginsenoside Rd reduces oxidative stress damage induced by H2O2 in microglia cells

Objective To investigate the effect of ginsenoside Rd on oxidative stress induced by H2O2 in microglia cells and the changes of biological function of microglia cells. Methods The microglia cell lines N9 were divided into control group, ginsenoside Rd group, H2O2 group, ginsenoside Rd 10 μmol/L+ H2O2 group and ginsenoside Rd 20 μmol/L+ H2O2 group. In the control group, the N9 cells were incubated in the CO2 incubator for 24 h; in the ginsenoside Rd group, the N9 cells were treated with 20 μmol/L ginsenoside Rd for 24 h; in the H2O2 group, the N9 cells were treated with 700 μmol/L H2O2 for 24 h; the cells in ginsenoside Rd 10 μmol/L+H2O2 group and ginsenoside Rd 20 μmol/L+ H2O2 group were pretreated with 10 μmol/L or 20 μmol/L ginsenoside Rd for 24 h, respectively, and then, 700 μmol/L H2O2 was added to the medium and co-cultured for another 24 h. After the treatment, the cell viability was measured by MTT assay, the intracellular reactive oxygen species(ROS)level was determined by 2',7'-dichlorofluorescein diacetate(DCFH-DA)and mitochondrial membrane potential(MMP)was measured by tetramethylrhodamine methyl ester(TMRE). Western blotting was used to detect the expression of brain derived neurotrophic factor(BDNF)in N9 cells. Results As compared with those in the control group and ginsenoside Rd group, the cell survival rate was significantly decreased, ROS level was significantly increased and MMP was significantly decreased in H2O2 group(P<0.05); as compared with the control group, the BDNF expression in ginsenoside Rd group was higher, and the difference was statistically significant(P<0.05); as compared with H2O2 group, the cell survival rate, BDNF expression and MMP level increased significantly, ROS was significantly decreased in ginsenoside Rd 10 μmol/L + H2O2 group and ginsenoside Rd 20 μmol/L + H2O2 group(P<0.05). Conclusion Ginsenoside Rd could protect microglia cells from oxidative stress damage induced by H2O2, and could increase the secretion of BDNF, which has a significant protective effect on microglia cells. Key words: Ginsenoside Rd; Microglia cell; H2O2; Reactive oxygen species; Mitochondrial membrane potential; Brain derived neurotrophic factor