Lactobacillus gasseri TF08-1 ameliorates high-fat diet induced nonalcoholic fatty liver disease and regulates gut microbiota in mice

AIMS: This study aimed to investigate the therapeutic potential of Lactobacillus gasseri TF08-1, a gut bacterium isolated from healthy adolescents, in alleviating high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD). This followed our discovery of lipid metabolism-related genes in its complete genome. METHODS AND RESULTS: The high-precision complete genome map of L. gasseri TF08-1 was constructed for the first time, revealing enriched lipid metabolism pathways, including bile salt hydrolase activity and short-chain fatty acid (SCFA) production. After supplementing L. gasseri TF08-1 for 8 weeks in mice fed with a high-fat diet, the serum triglyceride (TG) level decreased by 41.95%, the hepatic total cholesterol (TC) level decreased by 35.09%, and the TNF-α level decreased by 42.91%. Meanwhile, the NAS score decreased by 3.66 points. The treatment significantly reduced hepatic lipid accumulation, lowered proinflammatory cytokines, and improved steatosis scores. Metagenomic analyses showed L. gasseri TF08-1 restored gut microbiota balance, significantly increasing the abundance of beneficial bacteria such as Faecalibacterium prausnitzii and Phocaeicola vulgatus, while also enriching fatty acid degradation pathways. CONCLUSIONS: Lactobacillu gasseri TF08-1 demonstrates probiotic efficacy against NAFLD through dual mechanisms: direct metabolic modulation and gut microbiota restoration. The lipid metabolism capacity encoded by its genome likely contributes to therapeutic effects.