Selenium enrichment enhances the alleviating effect of Lactobacillus rhamnosus GG on alcoholic liver injury in mice.

Selenium-enriched probiotics have attracted much attention due to the physiological activities of both probiotics and selenium (organic selenium). In this study, we investigated the mitigating effect of selenium-enriched Lactobacillus rhamnosus GG (LGG@Se) and its pathway on alcohol-induced liver injury (ALI) in mice. The results showed that LGG@Se was superior to LGG and sodium selenite in alleviating ALI. Oral LGG@Se effectively prevented lipid metabolism disorders and liver oxidative damage in mice caused by excessive alcohol intake. 16S amplicon sequencing showed that LGG@Se intervention increased the abundance of beneficial bacteria and suppressed the growth of harmful bacteria in the intestinal tract of over-drinking mice, and thus effectively modulated the homeostasis of intestinal flora, which were highly correlated with the improvement of liver function. Liver metabolomics analysis indicated that LGG@Se intervention altered liver metabolic profiling, and the characteristic biomarkers were mainly involved in amino acid metabolism, including alanine, aspartate and glutamate metabolism, arginine biosynthesis, etc. In addition, LGG@Se intervention modulated the expression of genes and proteins related to lipid metabolism and oxidative stress in liver of over-drinking mice. Western blot analysis revealed that LGG@Se intervention up-regulated the expression of intestinal barrier function-related proteins, thereby ameliorating alcohol-induced intestinal barrier damage. Collectively, these findings provide scientific evidence that LGG@Se possesses the biological activity of improving alcohol-induced lipid metabolism and intestinal microbiota disorder.