Effect of flavonoid extract of mulberry leaf on serum adiponectin, visfatin and lipid profile levels in type 2 diabetic rats

Introduction: Diabetes mellitus is a metabolic disorder characterized by dysregulation of carbohydrate metabolism. White mulberry has been used over the centuries in medicine as a common agent to treat a variety of conditions including diabetes. The effect of ethanolic mulberry leaf extract (MLE) and mulberry leaf powder (MLP), on glycemic control, serum adiponectin, visfatin and lipid profile in type2 diabetic rats have been investigated.

Methods: 30 male wistar rats randomly divided into 5 groups. One group was randomly assigned as control (I) and diabetes was induced in others by administration of streptozotocin (55 mg/kg body weight) 15 minutes after the administration of nicotinamide (110 mg/kg body weight) intraperitoneally. Diabetic rats randomly divided as follow: diabetic control (II), sham (receiving of ethanol) (III), diabetic rats treated with MLE (receiving 600 mg/kg/day of MLE) (IV), and diabetic rats treated with MLP (receiving of MLP at 25% in the diet) (V). Finally, FBG, lipid profile, adiponectin and visfatin were assessed after 6 weeks.

Results: Serum FBG, total cholesterol, triglycerides, LDL-c, VLDL and visfatin significantly decreased and HDL-c and adiponectin increased in the two groups of treated diabetic rats in comparison to the diabetic control (p < 0.05). For all the investigated factors, there was no significant difference between two treatment methods. However, MLP was more effective than MLE in improving visfatin.

Conclusion: This study showed that MLE and MLP possess hypoglycemic and hypolipidemic activities and play an important role in regulating the secretion of Adipokines such as Adiponectin and Visfatin.