Inhibitory effect of euscaphic acid and tormentic acid from the roots of Rosa rugosa on high fat diet-induced obesity in the rat

The roots of Rosa rugosa have been used to treat diabetes mellitus in the folkloric society of Korea. To demonstrate the active component for the rat obesity induced by high fat diet for 6 weeks, the phytochemical fractionation and the pharmacological activity test were performed on this crude drug. It was shown that the methanolic extract and its EtOAc fraction inhibited the weight increase of the rat body, abdominal fat pad and hyperlipidemia at 200 mg/kg dose. Further, the triterpenoids, euscaphic acid and tormentic acid, isolated from R. rugosa roots were active at 30 mg/kg in the same assay. The two components shifted serum total-, HDL, and LDL-cholesterol levels toward the values of the unteated group, suggesting that the active compounds has hypolipidemic effects. The rats fed euscaphic acid and tormentic acid also reduced thiobarbituric acid-reactive substance (TBARS) and hydroxyl radical in the rat blood and increased Superoxide dismutase activity compared to the control. TBARS values and carbonyl content of the hepatic protein were reduced by treatment with the two triterpenoids. Antioxidative enzyme (SOD, glutathione peroxidase, and catalase) activities in hepatic tissues were increased by treatment of rats with the triterpenoids, which suggests that triterpenoids inhibited the reduction of hepatic antioxidative activity caused by high fat diet. Taken together, these results support that euscaphic acid and tormentic acid improve a high fat diet-induced hyperlipidemia via the activation of antioxidative mechanism.