Polygonatum sibiricum saponin Exerts Beneficial Hypoglycemic Effects in Type 2 Diabetes Mice by Improving Hepatic Insulin Resistance and Glycogen Synthesis-Related Proteins

Abstract

Type 2 diabetes mellitus (T2DM) is a systemic metabolic disorder characterized by insulin deficiency and insulin resistance. Recently, it has become a significant threat to public health. Polygonatum sibiricum saponin (PSS) has potential hypoglycemic effects, but its specific mechanism needs further study. In this study, PSS significantly decreased the level of blood glucose, water intake, and the organ index in diabetic mice. Meanwhile, PSS effectively reduced the content of total triglyceride (TG), total cholesterol (TCHO), low-density lipoprotein cholesterol (LDL-C), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) in the blood, and increased the content of high-density lipoprotein cholesterol (HDL-C). This suggests that PSS could reduce the content of blood lipids and initially improve the damage of hepatocytes. We found that PSS alleviated hepatic insulin resistance, repaired islet beta cells, and enabled insulin to play its biological role normally. It also improved oral glucose tolerance and abated serum lipopolysaccharide (LPS) and glycosylated hemoglobin (HbA1c) levels in T2DM mice. Furthermore, studies have found that PSS increased the content of phosphorylated protein kinase B (AKT), thereby promoting the effect of glucose transporter 4 (GLUT-4), and activating glycogen synthase kinase 3beta (GSK-3β) and glycogen synthase (GS) proteins to promote hepatic glycogen synthesis. Finally, we found that PSS could promote the growth of beneficial bacteria such as Bifidobacterium and Lactobacillus, reduce the growth of harmful bacteria such as Enterococcus and Enterobacter, and preliminarily improve the composition of important bacteria in the intestine. These studies indicate that PSS has an excellent hypoglycemic effect, which provides a potential new treatment for T2DM and guidance for more in-depth research.

Therapeutic mechanisms of the medicine and food homology formula Xiao-Ke-Yin on glucolipid metabolic dysfunction revealed by transcriptomics, metabolomics and microbiomics in mice

“…Importantly, the gut microbiota exhibited a definite inverse correlation with FBG, OGTT-AUC, ITT-AUC, insulin, HOMA-IR, inflammatory factors (IL-6 and TNF-α), liver TC and TG and serum TC, TG and FFA. This result is also in accordance with the results of previous studies, which suggest that the main active substances in Polygonatum sibiricum has an excellent hypoglycemic and Hypolipidemic effects and could promote the growth of beneficial bacteria such as Lactobacillus [ 54 , 55 ]. In contrast, some other differential microbiota including Clostridia at the class level, Lachnospircaeae and Tannerellaceae at the family level and Parabacteroides and Blautia at the genus were elevated in the Model group and depleted upon XKY administration.…”

Bioactive phytochemicals and associated multifunctional health-promoting effects of Polygonati Rhizoma

“…2) have been isolated from ethanol and methanol extracts of Polygonati Rhizoma [41][42][43]. Steroidal saponins of Polygonati Rhizoma have been majorly found for their hypoglycemic, anti-inflammatory, immunoregulation, and anti-diabetic activities [44]. The main mono-sugar residues existing in steroidal saponins are Glu, Gal, Rha, Ara, Xyl, and Fru (Fig.…”

Traditional herbs: mechanisms to combat cellular senescence

“…In studies based on hyperlipidemic and obese mouse models, Thujaplicins reduced the expression levels of SREBPs and PPARα and exerted regulatory lipid metabolism and antiinflammatory effects through activation of the AMPK signaling pathway [122,123]. In studies based on T2DM mice, Thujaplicins and aqueous extracts of C. tigris reduced blood glucose levels and blood lipid levels in mice, and Thujaplicins also repaired pancreatic β-cells to improve disorders of glucolipid metabolism [124,125].…”