Xiao-Gao-Jiang-Zhuo-containing serum inhibits adipogenesis through SIRT1-IGF-1 crosstalk in 3T3-L1 preadipocytes.

ABSTRACT

PPARγ, CEBP/α, and SREBP1C are the major transcriptional factors participating in adipogenesis and lipogenesis. SIRT1 and IGF-1 signaling pathways are important pathways involved in body endocrine and metabolism. Our unique Chinese herbal medicine Xiao-Gao-Jiang-Zhuo (XGJZ) has a remarkable clinical effect on obesity. However, the molecular basis remains unknown. XGJZ-containing serum was treated in the incubation of 3T3-L1 preadipocytes to observe its function in the 3T3-L1 cell differentiation. Oil Red O staining was used to monitor the lipid droplets accumulated after 8 days of incubation. RT-qPCR and western blotting were used to investigate the regulatory effects of XGJZ-containing serum on adipogenesis-related factors. The protein levels of main molecules in SIRT1 and IGF-1 signaling pathways were also detected by western blotting. XGJZ-containing serum notably suppressed the lipid accumulation in differentiated adipocytes through SIRT1/IGF-1 pathway. XGJZ-containing serum activated the SIRT1/IGF-1 pathway and reduced the expression levels of PPARγ, CEBP/α, and SREBP1C through this pathway. Additionally, XGJZ-containing serum enhanced the phosphorylation of ATGL and HSL and then induced lipolysis. XGJZ-containing serum has inhibitory effects on adipogenesis in 3T3-L1 preadipocytes through SIRT1/IGF-1 signaling pathway. Our study affirmed the effect of XGJZ-containing serum in the treatment of obesity. It provides a basis for the mechanism of obesity.