Dietary Gnaphalium affine supplementation prevents fat accumulation and inflammation by regulating composition and metabolism of gut microbiota in high fat diet fed mice

The aim of this study was to expose anti-obesity effect of Gnaphalium affine (GA) and its underlying mechanism by combining biochemical analysis, 16S rRNA sequencing and untargeted metabolomics. The results showed GA alleviated high-fat diet (HFD)-mediated oxidative stress, fat accumulation and inflammation. Moreover, GA improved gut barrier and immunity in HFD-fed mice through up-regulating tight junction protein, decreasing Lipopolysaccharide (LPS) level and inhibiting pro-inflammatory makers production in LPS/ toll-like receptor 4 (TLR4) / Myd88 / NF-κB pathway. Additionally, GA and its extracts altered composition and metabolism of gut microbiota. GA promoted abundances of Dubosiella and decreased abundance of Alistipes in HFD-fed mice, which were closely linked to 5-Hydroxy-6,7-dimethoxylflavone from GA and levels of weight, inflammatory markers, gut microbial metabolites of mice. Collectively, GA offers its anti-obesity properties through regulating gut microbiota by mucosal barrier functions, indicating that GA and its natural compounds hold great potential as a functional food ingredient.