β-Glucan from Lyophyllum decastes regulates gut microbiota and plasma metabolites in high-fat diet-induced obese mice

This study aimed to investigate the effects of Lyophyllum decastes β-glucan (LDBG) in preventing high-fat diet (HFD)-induced obesity in male C57BL/6 mice, focusing on fecal gut microbiota (GM) and plasma metabolomics. LDBG treatment led to a reduction in body weight and an improvement in dyslipidemia in the HFD-fed mice. Additionally, LDBG decreased pro-inflammatory factors (TNF-α, IL-1β, and IL-6) in liver and abdominal adipose tissue and lowered lipopolysaccharide and leptin levels in plasma. LDBG also up-regulated mRNA levels of intestinal epithelial tight junction proteins, such as Occludin, Claudin-1, and zonula occludens-1 in colon tissue. Furthermore, 16S rRNA gene sequencing data suggested that LDBG reduced the relative abundance of Faecalibaculum and Ileibacterium while increasing that of Bifidobacterium and Oscillospiraceae. Untargeted metabolomics showed that LDBG significantly promoted Tryptophan metabolism, Glycerophospholipid metabolism, and the Citrate cycle, closely correlating with GM changes, particularly in Oscillospiraceae genera. This study demonstrates the potential of LDBG as a prebiotic in obesity prevention by regulating metabolite pathways.