Abstract: Objective: The objective of this research was to study the hypoglycemic effect of the combined extract of pumpkin, yam, kudzuvine root and mulberry leaves on alloxan-induced diabetic mice. Methods: A diabetic mouse model was induced by alloxan. Another 10 mice served as a normal group. The model diabetic mice were randomly divided into model group, positive group (acarbose, 200 mg/kg mb) and low and high dose treatment groups (12 and 36 g dry raw material/kg mb). After intragastric administration for 4 weeks, we studied the effect of the combined extract on the body weight, food and water intake, fasting blood glucose level, glycogen, serum insulin, glycosylated serum protein (GSP), glycosylated hemoglobin (GHb) and antioxidant status of diabetic mice. Results: The major bioactive components of the combined extract were pumpkin polysaccharide, yam polysaccharide, and puerarin at levels of (0.93 ± 0.04), (1.01 ± 0.06), and (0.28 ± 0.01) g/100 g dry raw material, respectively. Compared with the model group, the body weight and glycogen content of mice in the intervention group were significantly improved, while the food and water intake, fasting blood glucose, GSP and GHb were decreased significantly. The insulin sensitivity was also improved. The hypoglycemic effect of the high dose group was better than that of the low dose group. Meanwhile, compared with the model group, the total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activity in the liver of mice administered with the combined extract were increased, while the content of malondialdehyde (MDA) was decreased. Thus, it was suggested that oxidative stress in diabetic mice was improved by administration of the combined extract. Conclusion: The combined extract of pumpkin, yam, kudzuvine root and mulberry leaves can effectively reduce the blood glucose level of alloxan-induced diabetic mice and improve oxidative stress.

Key words: hypoglycemic, combined plant extract, alloxan, oxidative stress