Hypoglycaemic effect and mechanism of an RG-II type polysaccharide purified from Aconitum coreanum in diet-induced obese mice

The present study aimed to explore the effect of an anti-inflammatory RG-II type polysaccharide (KMPS) purified from Aconitum coreanum (Le'vl.) on glucose metabolism in high-fat diet-induced obese (DIO) mice. Treatment with KMPS for 4 weeks significantly reduced the fasting blood glucose, increased the sensitivity to insulin and improved glucose tolerance. Concurrently, KMPS supplementation also markedly inhibited inflammatory cytokine expression in serum and insulin target tissues and decreased the proportion of MI-type macrophages in adipose tissue, which was considered as the potential hypoglycaemic mechanism. In mechanism study, it was found that KMPS reduced the serine phospholylation of IRS-1 by inhibiting the activation of the NF-kappa B pathway, thereby restoring the utilization of glucose by the PI3K/AKT pathway. These results suggested that KMPS may be a potential component for targeting inflammation in the treatment of type 2 diabetes. (C) 2020 Elsevier B.V. All rights reserved.