Hericium erinaceus insoluble dietary fiber alleviates obesity induced by high-fat diet through regulating the metabolic pathway influenced by gut microbiota

Hericium erinaceus (HE) is an important common edible mushroom, which is rich in dietary fiber. The objective of this study is to explore the potential lipid-reducing impact and regulation mechanism of Hericium erinaceus insoluble dietary fiber (HEIDF) by intervening mice caused by high-fat diet (HFD). The results demonstrated that HEIDF could significantly reduce hyperlipidemia induced by HFD and deposition of lipid droplets in liver and adipose cells to achieve the effect of lipid reduction. The 16S rRNA sequencing results of fecal bacteria indicated that HEIDF intervention significantly increased the abundance of Bacteroidota , norank_f_Muribaculaceae and Akkermansia , while reducing the abundance of Firmicutes and Desulfovibrio . Serum metabolomics revealed that HEIDF decreased the content of 2-isopropylmalic acid, 3-isopropylmalic acid and inosine. Relying on the correlation analysis between serum metabolites and gut microbiota, we found that with the increase of Akkermansia , norank_f_Muribaculaceae, and Acinetobacter , glycerides, bile acids, alcohols and their derivatives, fatty acids and acid conjugates of the serum were decreased. KEGG pathway enrichment showed that HEIDF could regulate the valine, leucine and isoleucine biosynthesis by improving the above gut microbiota. Therefore, this research indicated that HEIDF intervention increased the abundance of Akkermansia and norank_f_Muribaculaceae in gut microbiota, led to changes in valine, leucine and isoleucine biosynthesis, and then reduced the production of metabolites such as glycerides, bile acids, alcohols and their derivatives, which provided new insights for improving the mechanism of obesity and laid a theoretical foundation for improving the utilization rate of HEs and promoting functional foods rich in dietary fiber. Outline diagram . The purpose of this study is to explore the potential lipid-reducing effect and regulation mechanism of HEIDF by intervening mice induced by HFD. It was found that oral administration HEIDF markedly decreased body weight of HFD induced obese mice and buildup of fat droplets in liver and adipocytes to bring about lipid reduction, while concurrently elevating glucose tolerance. HEIDF intervention increased the abundance of Akkermansia and norank_f_Muribaculaceae in gut microbiota, led to changes in valine, leucine and isoleucine biosynthesis, and then reduced the production of metabolites such as glycerides, bile acids, alcohols and their derivatives, and played a functional role in reducing obesity caused by HFD. These outcomes implied that HEIDF intervention can relieve obesity by improving gut microbiota and lipid metabolism dysregulation by HFD feeding. Our work offers a new perspective on alleviation effect of HEIDF on up-modulating the abundance of Akkermansia and norank_f_Muribaculaceae in gut microbiota, led to obesity. Meanwhile, emphasizes the great potential of the HEIDF in HFD-induced obesity and gut dysbacteriosis, lipid metabolism abnormality and developing functional foods rich in dietary fiber. • HEIDF significantly reduced weight gain and visceral fat accumulation of obese mice. • HEIDF significantly alleviated HFD-induced dyslipidemia. • HEIDF ameliorated HFD-induced gut microbiota dysbiosis. • HEIDF prevented mice obesity via gut microbiota regulation. • HEIDF can alleviate lipid metabolism disorders caused by HFD.