Abstract: Objective: To explore the repairing effect of water-soluble polysaccharide from corn (WSPC) on islet immune damage in diabetic rats. Methods: Streptozotocin (STZ) was used to establish diabetic rat models via intraperitoneal injection. The successfully established models were randomly divided into three groups administered with WSPC at low, middle and high doses, as well as the model control group. WSPC administration was carried out by gavage for 28 consecutive days. The changes in blood sugar index, INS, HOMA-IS, and the contents of GAD-Ab, ICA and IAA in the diabetic rats were determined. Results: Compared with the model control group, blood glucose levels in treatment groups administered with WSPC at the low, middle and high doses were significantly decreased in a dose-dependent manner (P ＜ 0.05). Meanwhile, INS was increased with increasing WSPC dose and revealed a significant difference between the three treatment groups and the model control group (P ＜0.05). Compared with the normal control group, HOMA-IS in each WSPC group had a significant difference; however, no obvious difference in each WSPC was observed. In addition, compared with the model control group, GAD-Ab and IAA in the high-dose group did not exhibit an obvious difference; in contrast, ICA revealed a significant difference betweeb the middle-dose and high-dose groups. Conclusion: WSPC can promote insulin secretion in pancreatic islet β cells through rehabilitation of autoimmune injury and significantly increase serum insulin level (P ＜0.05), thereby playing an important role in reducing blood glucose level.

Key words: polysaccharides, diabetes, streptozotocin, antibody, islet cell