Effects of extract from Angelica keiskei and its component, cynaroside, on the hepatic bromobenzene-metabolizing enzyme system in rats.

The effects of Angelica keiskei Koidz. on hepatic lipid peroxide and the activities of free radical generating and scavenging enzymes were investigated in bromobenzene-induced hepatic lipid peroxidation in rats. The level of lipid peroxide elevated by bromobenzene was significantly reduced by the methanol extract from the aerial parts of A. keiskei and its component, cynaroside. Epoxide hydrolase activity was decreased significantly by the treatment of bromobenzene. However, the enzyme activity was restored in the liver of rats given the methanol extract and cynaroside. The results suggest that the reduction of bromobenzene-induced hepatic lipid peroxidation by the extract of A. keiskei and cynaroside under our experimental conditions is thought to be through enhancing the activity of epoxide hydrolase, an enzyme removing bromobenzene epoxide.