The University of Missouri School of Medicine has discovered a link between high-fat, high-sugar Western diets and the development of non-alcoholic fatty liver disease, the leading cause of chronic liver disease.
The study, conducted at MU's Roy Blunt NextGen Precision Health Building, identified the western diet-induced microbial and metabolic contributors to liver disease, advancing our understanding of the gut-liver axis and, as a result, the development of dietary and microbial interventions for this global health threat.
"We're just beginning to understand how food and gut microbiota interact to produce metabolites that contribute to the development of liver disease," said co-principal investigator, Guangfu Li, PhD, DVM, associate professor in the department of surgery and Department of Molecular Microbiology and Immunology.
"However, the specific bacteria and metabolites, as well as the underlying mechanisms were not well understood until now. This research is unlocking the how and why."
The gut and liver have a close anatomical and functional connection via the portal vein. Unhealthy diets change the gut microbiota, resulting in the production of pathogenic factors that impact the liver.
By feeding mice foods high in fat and sugar, the research team discovered that the mice developed a gut bacteria called Blautia producta and a lipid that caused liver inflammation and fibrosis.
That, in turn, caused the mice to develop non-alcoholic steatohepatitis or fatty liver disease, with similar features to human disease.
"Fatty liver disease is a global health epidemic," said Kevin Staveley-O'Carroll, MD, PhD, professor in the department of surgery, one of the lead researchers.
"Not only is it becoming the leading cause of liver cancer and cirrhosis, but many patients I see with other cancers have fatty liver disease and don't even know it. Often, this makes it impossible for them to undergo potentially curative surgery for their other cancers."
As part of this study, the researchers tested treating the mice with an antibiotic cocktail administered via drinking water. They found that the antibiotic treatment reduced liver inflammation and lipid accumulation, resulting in a reduction in fatty liver disease.
These results suggest that antibiotic-induced changes in the gut microbiota can suppress inflammatory responses and liver fibrosis.