Capillarisin (Cap), a main constituent of Artemisia capillaris (Compositae), was studied for its antioxidant bioactivity. In the preliminary study, Cap expressed a antioxidant property by its capacity for quenching the free radicals of 1,1-diphenyl-2-picrylhydrazyl (DPPH). This antioxidant bioactivity of Cap was investigated further using a model of t-butylhydroperoxide (t-BHP)-induced cytotoxicity and genotoxicity in rat primary hepatocytes. Results presented here demonstrate that Cap, at concentrations of 0.01-1.00 mg/ml, significantly decreased the leakage of lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) and the formation of malondialdehyde (MDA) induced by 30 min treatment of t-BHP (1.5 mM) in primary cultured rat hepatocytes. Cap also attenuated the t-BHP-induced diminution of glutathione (GSH) and high level of DNA repaired synthesis. These results lead to speculation that Cap presents inhibitory effects against t-BHP-caused cytotoxicity and genotoxicity in rat primary hepatocyte cultures at least via two distinct pathways, stabilizing the GSH system and quenching free radicals.
