Binary Bacillus subtilis protects the intestinal mucosa barrier and alleviates nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is characterized by liver steatosis, inflammation, and even fibrosis. NASH is likely to develop into cirrhosis and liver cancer, the major causes of liver related deaths. We aimed to study the effect of probiotics on NASH via the gut-liver axis.Thirty male Sprague-Dawley rats were divided into three groups. A control group of 10 rats was fed on a standard chow for 16 weeks. Twenty rats fed on a high-fat diet for 8 weeks were separated to two groups: a model group (10 rats) fed on vehicle for 8 weeks and a treatment group (10 rats) supplemented with binary Bacillus subtilis for 8 weeks. Hepatic expression of IL-6 and TNF-ɑ and ileum expression of IL-17 and occludin were measured.The high-fat diet caused inflammation of the liver and ileum in rats. Binary Bacillus subtilis treatment reduces liver inflammation through the intestinal liver axis. Increased levels of IL-6 and TNF-α were detected in rats fed a high-fat diet, which were reduced to lower levels after treatment with binary Bacillus subtilis. In rats on the high-fat diet, elevated IL-17 levels and decreased occludin levels were observed. Treatment with Bacillus subtilis reduced IL-17 levels and restored the expression of occludin.Binary Bacillus subtilis has a beneficial effect on liver inflammation and intestinal damage.