Abstract:

Abstract:Objective To investigate the effects of berberine on vascular endothelial function in type 2 diabetic rats and explore the prophylactic and therapeutic significance and pharmacological mechanism of berberine in type 2 diabetic vascular complications. Methods Wistar rats were randomly divided into four groups: diabetic group,control group,diabetic rats treated with berberine (100 mg·kg-1) group,and control rats treated with berberine group. The serum fasting blood glucose(FBG),insulin,total cholesterol(TC),triglyceride(TG) and fasting insulin(FINS) levels were tested. Acetylcholine (ACh)-induced endothelium-dependent relaxation and sodium nitroprusside
-induced endothelium-independent relaxation were measured in aortas for estimating endothelial function. In addition,the histopathology measurement was  performed with  hematoxylin and eosin staining. Results Compared with diabetic group,the FBG,TC and TG levels in diabetic rats treated with berberine were significantly decreased,meanwhile the insulin sensitivity index(ISI) was increased. The  Ach-induced endothelium-dependent relaxation in the aorta from diabetic rats was  significantly improved in berberine treatment group,while sodium nitroprusside (SNP)-induced endothelium-independent relaxation showed no difference among four groups. The histopathological results showed that berberine attenuated the  damage of the aortic endothelium in diabetic rats. However there was no difference in these indexes between control group and berberine treated control group. Conclusion Berberine restores diabetic endothelial dysfunction through decreasing the FBS and blood lipid,improving insulin resistant and enhancing NO bioavailability.

Key words: berberine;diabetes,mellitus experimental;vascular endothelium;endothelial dysfunction