Study of Wolfberry Polysaccharide on Diabetic Rats Induced by Streptozotocin

Objective:To investigate the effect of wolfberry polysaccharide on diabetic rats induced by streptozotocin.Method: Fifty male SD rats were injected peritoneally by streptozotocin(STZ) with a dose of 40 mg·kg-1 toestablish diabetic rat models.Successful rats model confirmed by detecting fasting blood-glucose(FBG) were randomly divided into 5 groups: normal control group,model group,rogridone group(0.4 g·kg-1·d-1),low-,medium-and high-dosage groups of wolfberry polysaccharide(0.4,0.8,1.6 g·kg-1·d-1).The rats in the normal and model control groups were given same volume of normal saline.The drugs were given to mice daily for 30 consecutive days.Glucose oxidase(GOD) method and radioimmunoassay(RIA) were used to examine the Fasting blood glucose(FBG);fasting insulin(FNS),the insulin sensitivity index(ISI) and insulin resistance(IR),enzyme-linked immunosorbent assay(ELISA) was used to determine serum leptin,tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6),iNOS expression in islet tissue was measured with RT-PCR assay.Result: Wolfberry polysaccharide significantly reduce the levels of blood-sugar,and effectively alleviate insulin levels(P0.01),reduce serum levels of inflammatory factor significantly(P0.01) and in addition,down-regulate iNOS mRNA expression in islets(P0.01).Conclution: The results suggest that wolfberry polysaccharide has the obvious hypoglycemic and hypolipidemic effects which is related to its improving antioxidant capacity and restoring islet function and inhibiting lipotoxicity.