The Effect of Ursolic Acid on the Blood Glucose Homeostasis and Insulin Resistance in Experimental Animals

The objective was to investigate the effect of ursolic acid (UA) on the blood glucose fluctuations and insulin resistance (IR) of the experimental animals as well as the potential mechanisms. The inhibition of UA on alpha-glycosidase activity and the effect of UA on postprandial blood glucose levels were investigated in rats using different doses; meanwhile the no fasting blood glucose (NFBC), the fasting blood glucose (FBC), and the glucose tolerance were measured by using a glucometer under in normal group, T2DM model group and UA treatment groups, respectively. Otherwise, the effect of UA on the glucose consumption of the HepG2 cell IR model was explored. The UA significantly inhibited alpha-glycosidase activity in vitro and the dose-effect relationship was seen. Meanwhile UA can also significantly restrain the increase of postprandial blood glucose levels in rats. The high dose UA reduced the increase of blood glucose levels significantly, similarly to acarbose (ACAR). In addition UA can decrease the FBC and NFBC of the T2DM IR model mice, but the amplitude was lower than that of the T2DM model mice and it can improve the glucose tolerance. UA can increase the glucose consumption of the HepG2 cell IR model with a dose-effect relationship. UA also had the capability of enhancing the utilization of glucose. In conclusion, UA had the ability of stabilization on the blood glucose of the diabetic mice through inhibiting the alpha-glycosidase activity and increasing the insulin sensitivity.