Ameliorative effects of <i>Bacillus subtilis</i> C10 on alcoholic liver injury in mice

Bacillus subtilis has been reported to maintain the homeostasis of intestinal flora. In this study, a mouse model of alcoholic liver injury (ALI) was constructed to study the ameliorative effect of B. subtilis C10 on ALI and to further clarify its mechanism of action. Significant correlations between intestinal flora and biochemical indicators of ALI were found by statistical correlation analysis. Supplementation with B. subtilis C10 modulated the equilibrium of gut flora by reducing the population of detrimental bacteria while enhancing the numbers of beneficial microorganisms, which resulted in an improvement in lipid metabolism and oxidative stress in the liver. The results of RT-qPCR showed that B. subtilis C10 intervention regulated the main regulatory factors of liver lipid metabolism (PPAR-α, SREBP-1c) and interfered with Nrf-2/Ho-1 signal pathway, which in turn ameliorated alcohol-induced lipid metabolism disorder and liver peroxidation stress. In addition, liver metabonomic analysis showed that B. subtilis C10 intervention reduced the production of harmful metabolites and increased beneficial metabolites in the liver, thereby reversing the metabolic disturbances caused by excessive alcohol consumption. KEGG analysis showed that B. subtilis C10 intervention modulated liver metabolic disorders and accelerated lipid metabolism by regulating glutathione metabolic pathway, purine metabolic pathway, pantothenic acid and CoA biosynthesis pathway, ABC transporter protein pathway, and HIF-1 signaling pathway. Taken together, these findings suggest that B. subtilis C10 ameliorates ALI by modifying the structure of intestinal flora and liver metabolic pathways to attenuate alcohol-exposure-induced liver oxidative damage and lipid metabolism abnormalities. PRACTICAL APPLICATION: Bacillus subtilis C10 is an effective probiotic intervention that significantly ameliorated alcoholic liver injury in mice through the gut-liver axis. B. subtilis C10 can be used as a dietary probiotic to develop functional foods with beneficial effects for the population of excessive alcohol consumption.