Abstract:

Objective: To discuss the hypoglycemic effects of saponins, flavonoids, and polysaccharides of fenugreek with different component compatibilities on the type 1 diabetic rats,and to study the optimal compatibility proportion of three kinds of components in reducing the blood glucose level.Methods: The saponins, flavonoids,and polysaccharides were extracted from the fenugreek and then they were separated and purified by column chromatography and decoction and alcohol sedimentation technique, respectively. The compatibility proportion of polysaccharides, flavonoids and saponins as well as the grouping were determined by uniform design method and the ratioes of three kinds of components to fenugreek. The administration groups were divided into low dose of polysaccharides compatibility group (polysaccharides:saponins:flavonoids 3:6:1), middle dose of polysaccharides compatibility group (polysaccharides:saponins:flavonoids 12:8:1),and high dose of polysaccharides compatibility group (polysaccharides:saponins:flavonoids 10:4:1). A total of 35 type 1 diabetic rats induced by streptozotocin(STZ) were divided into model control group (n=9), positive drug group (n=7) and low (n=6), middle(n=6), and high(n=7) doses of polysaccharides compatibility groups, respectively. Normal control group (n=11) was set up at the same time. The rats in normal control group and model control group were given pure water with the dose of 10 mL·kg^-1·d^-1. The metformin hydrochloride was administrated to the rats in positive drug group wtih the dose of 0.018 g·kg^-1·d^-1. The components of fenugreek were given to the rats in three doses of polysaccharides compatibility groups by the proportion mentioned above by intragastric administration for 28 d with the dose of 0.45 g·kg^-1·d^-1. The levels of fasting blood glucose(FBG), urinary protein in urine,serum triglyceride (TG), total cholesterol(TC), and advanced glycation endproducts(AGEs) in the rats were determined. The morphology of pancreas and kidney tissues of the rats were observed by HE staining.Results: The levels of FBG, urinary protein,serum TG, TC, and AGEs of the rats in model group were increased significantly (P<0.01) compared with normal control group. The levels of FBG of the rats in three doses of polysaccharides compatibility groups and positive drug group were decreased gradually and were decreased significantly on the 28th day after administration (P < 0.05 or P < 0.01) compared with model group; the levels of urinary protein,serum TG, TC, and AGEs were significantly decreased (P<0.01). The levels of urinary protein, TG, TC, and AGEs of the rats in low dose of polysaccharides compatibility group were decreased most significantly. The damage of pancreas and kidney tissues of rats in three doses of polysaccharides compatibility groups and positive drug group were improved compared with model group. Conclusion: The three components of fenugreek (polysaccharides:saponins:flavonoids) at the compatibility proportion of 3:6:1 can better regulate the blood glucose of type 1 diabetic rats and protect the pancreas and kidney tissues of rats.

Key words: component compatibility, fenugreek, saponins, flavonoids, diabetes mellitus, polysaccharides