Saponins from Panax japonicus alleviate adipose tissue fibrosis and metabolic dysfunction in high-fat-diet-induced obese mice

Abstract

Introduction: Adipose tissue fibrosis is a typical feature of adipose tissue dysfunction in obese individuals, which is closely related to metabolic diseases. Objective: To explore the effect and mechanism of Saponins from Panax japonicus (SPJ) on adipose tissue fibrosis in obese mice induced by high fat diet (HFD). Materials and methods: We established a HFD induced obese mice model. Then the obese mice were treated with 90 mg/kg SPJ by oral gavage for 10 weeks. The levels of adipose tissue fibrosis and molecules related to signaling pathways were measured. Then the effects of SPJ on TGFβ1- induced fibrosis in 3T3-L1 differentiated adipocytes were evaluated. Results: SPJ reduced body weight, fat accumulation, and improved glucose and lipid metabolism in obese mice. SPJ decreased collagen deposition and expressions of fibrotic genes in epididymal white adipose tissue (eWAT) of obese mice. SPJ decreased the levels of TGFβ1 protein and pSmad2, and increased the expression of PPARγ and PGC1α, thus alleviating oxidative stress in eWAT. Consistently, SPJ inhibited TGFβ1- induced fibrosis in 3T3-L1 differentiated adipocytes. Conclusions: SPJ may alleviate adipose tissue fibrosis and improve obesity by inhibiting TGFβ1/Smad2 and activating PPARγ/PGC1α pathway. SPJ is expected to become an efficient medicine for treatment of obesity.