Abstract
The present study was designed to evaluate the hypolipidemic effect of ursolic acid stearoyl glucoside (UASG) in high-fat diet-induced obesity. Two in vivo experiments such as high-fat diet-induced obesity mice model and lipid emulsion tolerance test in normal rats were performed. In vitro inhibition of pancreatic lipase activity was further measured to substantiate the results. In high-fat diet-induced obesity mice model, female Swiss mice were fed a high fat diet (HFD; 40% fat) with or without 1 or 2% of UASG or 0.012% orlistat for nine weeks. In lipid emulsion tolerance test male Wister rats were orally administered, lipid emulsion with or without 500 or 1000mg/kg of UASG and the plasma triglycerides were measured from 0.5 to 5h. Consumption of HFD containing UASG to mice for nine weeks exhibited significant reduction in lipid parameters, body weight, parametrial adipose tissue weight, liver triglyceride (TG) and different organ weight compared to HFD fed control. Further it was noted the improvement in insulin resistance induced by the HFD alone group. Furthermore, consumption of an HFD containing 1 or 2% of UASG significantly increased the fecal content and fecal triglyceride compared with the HFD group. Pre-treatment with UASG inhibited the elevated plasma triglyceride level after the oral administration of the lipid emulsion to rats. Further, UASG significantly inhibits activity of pancreatic lipase at a concentration of 2.5mg/ml. Data obtained from the results indicated that UASG prevent high-fat diet-induced obesity in mice possibly by inhibiting pancreatic lipase activity.