Abstract:The anti-hyperglycemic effect of polysaccharides from Acanthopananx trifoliatus (L.) Merr. stem (ATMP) was investigated in streptozotocin (STZ)-induced diabetic mice. These mice were divided into six groups, a normal group, a high blood glucose group, a metformin group, an ATMP low-dose [50 mg/(kg?d)] group, an ATMP middle-dose [100 mg/(kg?d)] group, and an ATMP high-dose [200 mg/(kg?d)] group. Four weeks after dosing by intra-peritoneal injection, body weight, organ index, blood glucose, and oral glucose tolerance were examined for all groups, and morphological changes were determined by HE staining. The polysaccharides at doses of 100 mg/(kg?d) and 200 mg/(kg?d) decreased blood glucose significantly by 47.73% and 53.52%, respectively, and increased oral glucose tolerance. The AUC of mice in the 100 mg/(kg?d) and 200 mg/(kg?d) ATMP group were significantly lower than those in the high blood glucose group. ATMP at these doses also increased the thymus index by 48.9% and 51.1%, respectively. HE staining showed that ATMP had a therapeutic effect on the pancreas and spleen. The results showed that ATMP has an anti-hyperglycemic effect, and this may occur through some form of immune regulation.