Abstract: Objective: The aim of this study was to investigate the protective effect of flavonoids from peony stamens (PSF) against hydrogen peroxide (H2O2)-induced injury in RAW264.7 cells. Methods: This experiment was divided into blank, model, control and low-, medium- and high-dose PSF groups. RAW264.7 cells were injured by H2O2 and the cell viability was measured by methyl thiazolyl tetrazolium assay. The contents of malondialdehyde (MDA) and glutathione (GSH) and the activities of catalase (CAT), superoxide dismutase (SOD) and lactate dehydrogenase (LDH) inside the cells and in the culture medium were determined by commercial kits. Results: The flavonoids at concentrations in the range of 10–30 μg/mL significantly enhanced the proliferation of RAW264.7 cells (P < 0.05). Compared with the model group, the flavonoids at all concentrations could increase total antioxidant capacity (T-AOC), the activities of glutathione peroxidase (GSH-Px), SOD and CAT and GSH content, reduce MDA content in the cultured cells and culture medium and improve LDH activity in the cells. Conclusion: Flavonoids from peony stamens can enhance the proliferation of RAW264.7 cells and protect them against H2O2-induced toxicity in a dose-dependent manner.

Key words: peony stamen, flavonoid, RAW264.7 cells, antioxidant capacity