Salvianolic acid B inhibited PPARγ expression and attenuated weight gain in mice with high-fat diet-induced obesity.

ABSTRACT

BACKGROUND/AIMS: Obesity contributes to the development of cardiometabolic disorders such as type 2 diabetes, fatty liver disease and cardiovascular disease. Salvianolic acid B (Sal B) is a molecule derived from the root of Salvia miltiorrhiza (Danshen), which is a traditional Chinese medicine that is widely used to treat cardiovascular diseases. However, the role of Sal B in obesity and obesity-related metabolic disorders is unknown. In this study, we aimed to investigate the effects of Sal B on high-fat diet-induced obesity and determine the possible mechanisms involved. METHODS: Male C57BL/6J mice fed a high-fat diet for 12 weeks received a supplement of Sal B (100 mg/kg/day) by gavage for a further 8 weeks. These mice were compared to control mice fed an un-supplemented high-fat diet. 3T3-L1 preadipocytes were used in vitro studies. RESULTS: Sal B administration significantly decreased body weight, white adipose tissue weight, adipocyte size and lipid (triglyceride and total cholesterol) levels in obese mice. Eight weeks of Sal B administration also improved the intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test (IPITT) scores in high-fat diet-induced obese mice. In 3T3-L1 preadipocytes that were cultured in vitro and induced to differentiate, Sal B reduced the accumulation of lipid droplets and lipid content in a dose-dependent manner. Immunoblotting indicated that Sal B decreased peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer binding protein α (C/EBPα) expression but increased the expression of GATA binding protein 2 and 3 (GATA 2, GATA 3) both in vivo and in vitro. CONCLUSION: Our data suggest that Sal B may reduce obesity and obesity-related metabolic disorders by suppressing adipogenesis. The effects of Sal B in adipose tissue may be related to its action on PPARγ, C/EBPα, GATA-2 and GATA-3.