Potential hepatotoxicity of geniposide, the major iridoid glycoside in dried ripe fruits of Gardenia jasminoides (Zhi-zi).

The safety of geniposide, mainly focusing on its hepatotoxicity in rats, was determined by liver enzymes in serum and histopathology ultrastructural preparation. The lethal dose, 50% (LD50) of per oral geniposide was 1431.1 mg kg(-1). The acute toxicity study indicated geniposide at dose of 574 mg kg(-1) or more could cause hepatic toxicity in rats and the hepatotoxicity often appeared at 24-48 h after the oral administration. The hepatotoxicity was associated with oxidative stress with decrease of total superoxide dismutase activity and increase of malondialdehyde concentration in rats' livers. Subchronic toxicity study showed geniposide did not cause hepatotoxicity at the doses of 24.3 and 72.9 mg kg(-1) orally for 90 days in rats. Thus, acute hepatotoxicity of geniposide at high doses was likely to be linked to oxidative stress, while geniposide at normal dose of 24.3 mg kg(-1) or less did not cause hepatotoxicity even in the repeated dosing study.