Hypoglycemic Effects of a Polysaccharide from Tetrastigma hemsleyanum Diels & Gilg in Alloxan-Induced Diabetic Mice

Tetrastigma hemsleyanum Diels & Gilg, a well-known traditional Chinese medicine, possesses antitumor and anti-inflammatory activity, etc. However, the anti-diabetic effect has not been determined. In our present study, a water-soluble polysaccharide, named THP with molecular weight of 93307Da, was isolated from T. hemsleyanum by DEAE-52 ion-exchange and Sephadex G-100 chromatography. It contains rhamnose, arabinose, mannose, glucose, and galactose in the molar ratio of 0.07:0.14:0.38:0.21:0.31. Then anti-diabetic effects of THP were examined by treating alloxan-induced diabetic mice with different doses (100, 200, and 300mg/kg) of THP orally. The results showed that THP could decrease the blood glucose, TC, TG, LDL-C levels, increase the body weight, HDL-C, insulin levels, and enhance the activities of antioxidant enzyme system in alloxan-induced diabetic mice. Furthermore, the histopathological examination of pancreas, liver, and kidney indicated that THP could protect and reverse -cells in diabetic mice with low damage to liver and kidney, which suggests that THP may stimulate pancreatic release of insulin and can be an effectively potential candidate for diabetes mellitus.