Impact of mulberry leaf extract and mulberry leaf powder on serum nesfatin-1 level in nicotinamide/streptozotocin-induced type 2 diabetic rats

Introduction: The white mulberry leaves (Morus Alba L.) are used in traditional medicine as anti-diabetics, because it contains flavonoids, can act as insulin secretagogues or insulin mimetics. Nesfatin-1 is a novel anorexigenic regulatory peptide and affects glucose metabolism by increasing insulin sensitivity. We investigated the effect of Mulberry leaf extract (MLE) and Mulberry leaf powder (MLP) on Nesfatin-1; fasting blood glucose (FBG) and insulin levels in streptozotocin-nicotinamide (STZ-NA) induced type 2 diabetes.

Materials and methods: 30 male wistar rats were divided randomly into five groups. One of them was randomly selected as healthy control (I) and diabetes was induced in others by STZ 60 mg/kg body weight) and NA (110 mg/kg body weight). 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). FBG, insulin, nesfatin-1 were measured after 6 weeks.

Results: FBG was reduced and serum insulin levels were increased in treated rats compared to the diabetic control. Serum nesfatin-1 levels were significantly improved to near normal in MLP treated rats compared to the diabetic control. Effect of MLE on serum nesfatin-1 levels was the same as MLP but not significant.

Conclusion: MLE and MLP have potential hypoglycemic effect, probably by increasing insulin level and changing serum nesfatin-1 level. MLP was more effective than MLE in improving nesfatin-1, probably because of presence of ethanol in MLE.