Abstract: Objective To observe the hypoglycemic mechanism of total saponins of Momordica charantia(MC) in type 2 diabetes rats. Method: 8 rats were randomly selected as normal control group in 60 SPF SD rats. Other rats were used to build the type 2 diabetes models. The type 2 diabetes rats models were established by eating food containing the higher lipid and sugar and by intravenous injection of a low dose of streptozotocin. After the disease models were successfully induced, the model rats were then randomized into five groups: the model control group (n=8), the metformin group (n=8) and the three dose total saponins of MC group (n=24). The total saponins of MC group was administrated with total saponins of MC 100, 200, 400mg/(kg?d) for 8 weeks, the metformin group was administrated with metformin 50mg/(kg?d) for 8 weeks. At the end of the experiment, the fasting blood glucose and insulin were measured. At the same time, a part of pancreas islet, liver and skeletal muscle were preserved. The pancreas islet structure, the hepatic glycogen and Glucose transporter 4(GLUT4) expression were observed by electron microscope, glycogen dyeing and western blot methods respectively. Result:After 8 weeks treatment, compared to type 2 diabetes model group, fasting blood glucose and insulin values in MC group reduced more obviously, however, the amount of skeletal muscle GLUT4 expression, insulin granules and hepatic glycogen increased obviously in MC group. Conclusion: Total saponins of MC has the hypoglycemic activity. It’s mechanisms maybe include promoting the hepatic glycogen synthesis, inhibiting the hepatic glycogen decomposition and promoting insulin sensitivity by increasing peripheral tissue’s GLUT4 expression.

Key words: total saponins of Momordica charantia, type 2 diabetes, mechanism, hypoglycemic activity, GLUT4