Fusobacterium nucleatum promotes the development of acute liver failure by inhibiting the NAD+ salvage metabolic pathway

Abstract

BackgroundAcute liver failure (ALF) patients are often accompanied by severe energy metabolism abnormalities and intestinal microecological imbalance. The intestinal mucosal barrier is severely damaged. Intestinal endotoxin can induce intestinal endotoxemia through the "Gut-Liver axis". More and more evidence shows that members of the gut microbiota, especially Fusobacterium nucleatum (F. nucleatum), are related to inflammatory bowel disease, but whether F. nucleatum is involved in the development of ALF and whether it affects the liver energy metabolism is unclear.MethodsThis study first detected the abundance of F. nucleatum and its effect on ALF disease, and explored whether F. nucleatum aggravated liver inflammation in vitro and in vivo.ResultsOur data showed that liver tissues of ALF patients contained different abundances of F. nucleatum, which were related to the degree of liver inflammation. In addition, we found that F. nucleatum infection affected the energy metabolism of the liver during the development of ALF, inhibited the synthesis pathway of nicotinamide adenine dinucleotide (NAD+)'s salvage metabolism, and promoted inflammatory damage in the liver. In terms of mechanism, F. nucleatum inhibited NAD+ and the NAD+-dependent SIRT1/AMPK signaling pathway, and promoted liver damage of ALF.ConclusionsFusobacterium nucleatum coordinates a molecular network including NAD+ and SIRT1 to control the progress of ALF. Detection and targeting of F. nucleatum and its related pathways may provide valuable insights for the treatment of ALF.