Non-alcoholic fatty liver disease (NAFLD) and alcoholic fatty liver disease (AFLD) have increased prevalence and pose significant health burdens, globally. Both of these can advance to liver cirrhosis. Plethora of evidence have shown that the gut microbiome was related to NAFLD/AFLD development and progression. This study reviewed the present literatures on the microbiota, fatty liver disease, and liver cirrhosis based on Pubmed database. 

The study demonstrated that NAFLD was characterized by increased amounts of Lachnospiraceae from the phylum Firmicutes and Roseburia from the Lachnospiraceae family, and alcohol intake elevated the proportion of Enterobacteria and Proteobacteria. The authors reported reduced Bacteroidetes in cirrhosis. Thus, it can be concluded that microbiota can ameliorate or aggravate the above liver diseases via several mechanisms, including increasing liver lipid metabolism, increasing alcohol production, increasing intestinal permeability, bacterial translocation, intestinal bacterial overgrowth, enteric dysbiosis, and impairing bile secretion. Nevertheless, the exhaustion of these bacteria is required to substantiate their role in liver disease.

Source: Guohong-Liu, Qingxi-Zhao, Hongyun-Wei. Characteristics of intestinal bacteria with fatty liver diseases and cirrhosis. Ann Hepatol. 2019 Nov-Dec;18(6):796-803.