Fuding Zhou¹, Jinchuan Yu¹, Guangjun Wang², Ting Wang¹, Zhengxiang Liu¹, Wenjun Chen^1,

This study aimed to explore the protective effect of Polygonatum sibiricum aqueous extract (PSAE) on lipid metabolism in vivo. 72 mice were divided randomly into Polygonatum sibiricum polysaccharide (PSP) group, Control group, Model group, Low-, Medium-, and High-dose PSAE (0.5, 1, 2g/kg) groups, 12 mice in each group. In this experiment, 60% high-fat diets were used for 6 weeks. After 3 consecutive doses of 35mg/kg, an intraperitoneal injection of 1% streptozotocin (STZ) was used to induce type 2 diabetic mice (T2DM). Streptozotocin was dissolved in citric acid sodium citrate buffer solution in PH=4.4. Mice were treated with PSAE and PSP by gavage one week before modeling, and the gavage process lasted until the mice were killed. After one week of gavage treatment, the feeding diets of mice in the Model group, PSAE groups, and PSP group were all changed to a 60% high-fat diet. After feeding with a high-fat diet for 6 weeks, the mice were fasted overnight for 3 consecutive days and injected with 1% STZ intraperitoneally. The mice in the Control group were injected with the same volume of solvent as the same surgical control. The results showed that, compared to mice in the Model group, the levels of serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and liver triglyceride level were significantly decreased in the high-dose PSAE group. The composition and diversity of the gut microbiota were considerably altered by PSAE. In particular, high-dose PSAE lowered the relative abundance of the phyla Firmicutes and Bacteroidetes while increasing the relative abundance of the phylum Proteobacteria. At the genus level, high-dose PSAE decreased the relative abundance of Bacteroides, while significantly increasing the relative abundance of Parabacteroides and Alistipes. Besides, PSAE alleviated insulin resistance in type 2 diabetic mice. These results imply that PSAE may be a potential functional food for T2DM intervention by regulating gut microbiota and against lipid metabolism disorders.

type 2 diabetic, Polygonatum sibiricum aqueous extract, gut microflora