Effects of polysaccharide from pumpkin on biochemical indicator and pancreatic tissue of the diabetic rabbits.

A water-soluble polysaccharide (PCE-CC) was obtained from pumpkin which belongs to the family Cucubitaceae by the water and ethanol extract, organic solvent fractional extraction and deproteinization. The present study was designed to investigate PCE-CC possible mechanism underlying the improvement of damaged pancreatic islets. Alloxan-induced diabetic rabbits were injected with PCE-CC for 21 days to assess effects on islet tissue morphology. After 21 days, the weights of the alloxan-induced diabetic and non-diabetic rabbits fed with diet contained PCE-CC were significantly increased as compared to the negative group. The data of blood glucose (BG), total cholesterol (TC), total triglyceride (TG) and glycosylated hemoglobin (HbA1c) indicated that PCE-CC had beneficial effects on the improvement in the control of blood glucose, serum lipid and glycosylated hemoglobin levels. Observing the pancreatic tissue of the diabetic rabbits revealed that PCE-CC could promote the regeneration of damaged pancreatic islets by stimulating β-cell proliferation, which was accompanied by a decrease in plasma glucose levels. PCE-CC was further separated and purified to obtain PCE-CCH by ion exchange and gel chromatography. PCE-CCH was a heteropolysaccharide and consisted of glucose, galactose, arabinose, rhamnose and little amount of hexuronic acid, with a molecular weight of 1.15 × 10(5) Da.