Regulatory Effects Mediated by Enteromorpha prolifera Polysaccharide and Its Zn(II) Complex on Hypoglycemic Activity in High-Sugar High-Fat Diet-Fed Mice.

In order to investigate and develop functional foods of marine origin with hypoglycemic activity, Enteromorpha prolifera polysaccharide-Zn(II) (EZ) complex was first prepared by marine resourced E. prolifera polysaccharide (EP) and ZnSO4 and their anti-diabetes activities against high-sugar and high-fat-induced diabetic mice were evaluated. The detailed structural characterization of EZ was elucidated by UV-Vis spectroscopy, infrared spectroscopy, and monosaccharide composition determination. The pharmacological research suggests that EZ has a potent hypoglycemic effect on high-sugar and high-fat-induced diabetic mice by inhibiting insulin resistance, improving dyslipidemia, decreasing inflammatory status, repairing pancreas damage, as well as activating the IRS/PI3K/AKT signaling pathway and regulating GLUT2 gene expression. At the same time, microbiota analysis indicates that a high dose of EZ could enhance the abundance of dominant species, such as Staphylococcaceae , Planococcaceae , Muribaculaceae , Aerococcaceae , and Lacrobacillaceae , in intestinal microbiota distribution. Thus, EZ could be considered as a potential candidate for developing an ingredient of functional foods for Zn(II) supplements with hypoglycemic activity.