Abstract: The active ingredient of ginseng, ginsenosides Rg1, has been shown to scavenge free radicals and improve antioxidant capacity. This study hypothesized that ginsenosides Rg1 has a protective role in human neuroblastoma cells injured by H2O2. Ginsenosides Rg1 at different concentrations (50 and 100 μM) was used to treat H2O2 (150 μM)-injured SH-SY5Y cells. Results demonstrated that ginsenoside Rg1 elevated the survival rate of SH-SY5Y cells injured by H2O2, diminished the amount of leaked lactate dehydrogenase, and increased superoxide dismutase activity. Ginsenoside Rg1 effectively suppressed caspase-3 immunoreactivity, and contributed to heat shock protein 70 gene expression, in a dose-dependent manner. These results indicate that ginsenoside Rg1 has protective effects on SH-SY5Y cells injured by H2O2 and that its mechanism of action is associated with anti-oxidation and the inhibition of apoptosis.

Key words: nerve regeneration, traditional Chinese medicine monomer, ginsenoside Rg1, SH-SY5Y cells, H2O2, cerebral ischemia, cell apoptosis, lactate dehydrogenase, superoxide dismutase, caspase-3, heat shock protein 70, dose-effect relationship, neural regeneration