[Hypoglycemic effects of mulberry leaf extracts on diabetic mice].

OBJECTIVE: To study hypoglycemic effects of different mulberry leaf extracts on diabetic mice.

METHODS: STZ-induced diabetic mice were intragastricly administrated with different mulberry leaf extracts( water extracts: 800 mg/kg, ethanol extracts: 500 mg/kg, water extracts + ethanol extracts: low dose 150 mg/kg, high dose300 mg/kg) and positive control group( melbine: 227. 5 mg/kg). Four weeks later, serum glucose levels, insulin levels, antioxidase activities were tested. Liver and pancreas pathological changes were observed by HE staining.

RESULTS: Compared with model group, each mulberry leaf extracts group could decrease serum glucose and insulin levels and increase antioxidase activities. The mixture of water extracts and ethanol extracts at high dose showed the most obvious effects. In this group, serum glucose levels, insulin levels, insulin resistance index and insulin sensitivity index were 61. 0%, 64. 1%, 42. 9% and 1. 18 times of those in the model group( P < 0. 05), and no significant differences were found between this group and the positive group( P > 0. 05).

CONCLUSION: The mixture of mulberry leaf water and ethanol extracts showed synergistic hypoglycemic effects by increasing antioxidase activities, repairing pancrea and liver oxidative damages, and improving insulin resistance status.