Salvianolic acid B improves glucolipid metabolism by regulating adipogenic transcription factors in mice with diet-induced obesity

摘要

Objective:To determine the effect of Salvianolic acid B (Sal B) on glucose and lipid metabolism in mice with high-fat diet (HFD)-induced obesity,and to investigate the underlying mechanisms by measuring the expression levels of key adipogenic transcription factors.Methods:Six-week-old C57BL/6J male mice were fed for 12 weeks with a HFD to induce obesity or a standard diet to serve as normal controls.A mean body weight increase of more than 20% after these 12 weeks was used as the criteria for obesity.HFD-fed obese mice then received a supplement of Sal B (100 mg/kg body weight/day),metformin (75 mg/kg body weight/day) or water (an equivalent volume;served as model controls) by oral gavage for an additional 8 weeks,and the normal controls received water (an equivalent volume) by oral gavage for the same period.Results:Sal B significantly reduced body weight gain (P <.05) without influencing food intake in HFD-fed obese mice relative to model controls.Sal B also reduced the body fat mass of the obese mice relative to model controls in a time-dependent manner (P <.05).Sal B significantly decreased the serum concentrations of low-density lipoprotein cholesterol,total cholesterol,triglyceride and free fatty acids by 25.5%,20.2%,20.6% and 13.4%,respectively,and increased the concentration of high-density lipoprotein cholesterol by 50.1% relative to model controls.In addition,Sal B significantly lowered fasting glucose concentrations and improved insulin sensitivity relative to model controls (P <.05).Sal B acted by ameliorating the histopathological changes in both brown and white adipose tissues of obese mice.Moreover,in brown adipose tissue,Sal B up-regulated the mRNA and protein expression of PPARγ and c/EBPα,and the protein expression of PPARα and SREBP-1 (P <.05).In white adipose tissue,Sal B down-regulated the mRNA expression of PPARγ and c/EBPα,and decreased the protein expression of PPARγ and SREBP-1(P <.05).Conclusjons:The results suggest that Sal B can reduce body weight gain and regulate glucose and lipid metabolism in mice with diet-induced obesity by regulating adipogenic transcription factors in their adipose tissues.