Anti-type 2 diabetes mellitus mechanisms and structural characteristics of polysaccharides: A review.

Polysaccharides, present in a variety of plants, animals and fungi, exhibit extensive pharmacological activities, particularly anti-type 2 diabetes mellitus (T2DM) effects, which have attracted increasing attention. Herein, we critically analyze current research advances in anti-T2DM polysaccharides, including their associated signaling pathways and the structure-hypoglycemic activity correlation. This review focuses on elaborating the structure-activity relationship of polysaccharides against T2DM from four critical structural perspectives: 1. molecular weight; 2. monosaccharide composition; 3. glycosidic bond; 4. advanced structures. In addition, it provides a comprehensive analysis of polysaccharides' underlying therapeutic mechanisms. These mechanisms include improving insulin sensitivity, regulating glucose metabolism, exerting anti-inflammatory and antioxidant effects, modulating gut microbiota composition, influencing key metabolic enzymes, governing insulin and glucagon secretion. Overall, this review provides a detailed analysis of the structural characteristics of polysaccharides with anti-T2DM effects, and also offers novel insights for the development of polysaccharide-based hypoglycemic drugs.