Gut microbiota, host lipid metabolism and regulation mechanism of high-fat diet induced mice following different probiotics-fermented wheat bran intervention

Wheat bran (WB) was fermented by Lactobacillus rhamnosus, Lactobacillus plantarum, Lactobacillus brevis (LAB-FWB), respectively, and their corresponding mechanism of obesity alleviation via gut microbiota and lipid metabolism was investigated. Results indicated LAB-FWB reduced body weight and serum glucose, followed by an improved lipid profile in obese mice compared with WB. All LAB-FWB interventions led to an enriched steroid hormone biosynthesis. LGG-WB significantly up-regulated genes in arachidonic acid metabolism, bile secretion and linoleic acid metabolism. While LB-WB down-regulated genes in PPAR signaling pathway and LP-WB up-regulated genes in linoleic acid metabolism, indicate their different regulation patterns. Furthermore, LAB-FWB reduced Firmicutes/Bacteroidetes ratio and returned HFD-dependent bacteria Colidextribacter and Erysipelatoclostridium to be normalized. Interestingly, LAB-FWB significantly enriched lipid-related pathways, benefiting xanthohumol, prostaglandin F2alpha, LPI 18:2 and lipoamide biosynthesis in lipid metabolic pathway, but not found in WB group. Among them, treatment with LGG-WB exerted the greatest function on alleviating obesity syndromes.