Sarcodon aspratus polysaccharides ameliorated obesity-induced metabolic disorders and modulated gut microbiota dysbiosis in mice fed a high-fat diet

Sarcodon aspratus, a popular edible fungus that has commonly been used as a functional food in China and other Asian countries. This study is conducted to examine the potential health benefits of SATP, the polysaccharides isolated from the fruit body of S. aspratus, on obesity and related metabolism disorders. C57BL/6J mice were fed with high-fat diet (HFD) and supplemented with SATP (100-400 mg kg-1) for 14-week. The results indicated that SATP treatment markedly reduced HFD-induced body weight gain and fat accumulation in dose-dependent manner. SATP could improve lipid homeostasis and glucose tolerance in HFD-fed mice. Furthermore, SATP intervention significantly attenuated the hepatic steatosis, liver oxidative stress and inflammation. Additionally, we detected the macrophages and mRNA levels of lipogenesis marker in epididymal adipose tissues, results revealed that SATP exerted inhibitory effects on activation of immune cells and adipocyte differentiation in adipose tissues. High-throughput pyrosequencing of 16S rRNA suggested that SATP intervention was able to down-regulate the Firmicutes-to-Bacteroidetes ratio, also increased the relative abundance of Lactobacillus, Bacteroides and Akkermansia in mice with HFD challenge. Taken together, SATP possessed ameliorative effects in hepatic steatosis, inflammation and adipocyte differentiation in HFD-fed mice. Notably, SATP could modulate HFD-induced dysbiosis of gut microbiota. Thus, SATP might be a potential health supplement or prebiotic in the prevention of obesity and related metabolic disorders.