Butyrate Regulates Intestinal DNA Virome and Lipopolysaccharide Levels to Prevent High-Fat Diet-Related Liver Damage in Rats

As the adsorption receptor of bacteriophage tail protein, bacterial lipopolysaccharide (LPS) is a main culprit responsible for nonalcoholic fatty liver disease (NAFLD) caused by high-fat diets. However, few studies have focused on how the interaction between intestinal bacteriophages and bacterial LPS affects the development and progression of NAFLD. Herein, we determined that excessive fat intake significantly increases the levels of endogenous LPS, while the administration of beneficial metabolites of the intestinal microbiota (specifically butyrate) alleviated hepatic injury in rats. The beneficial mechanism of butyrate was attributed to the reprogramming of the structure of the intestinal DNA virome (primarily, phageome). Butyrate possesses the potential to augment bacteriophagic microbial diversity, thereby potentially facilitating interactions between intestinal bacteriophages and bacterial LPS (in the case of homologous phage), further improving mitochondrial dysfunction and reactive oxygen species production, which, in turn, lowered HepG2 cell damage. Likewise, fecal phage transplantation further confirmed that intestinal phages from rats that received butyrate could effectively interact with bacterial LPS to reduce liver damage in rats. Taken together, modifying the intestinal phageome is a promising treatment option for high-fat diet-related NAFLD.