The effective role of intestinal microbiota in nonalcolic fatty liver disease pathogenesis

Non-alcoholic fatty liver disease (NAFLD) is known to be the most common liver disease in the world, and there are currently no approved pharmacological treatments to prevent or treat this condition. In addition to being associated with an increased risk of hepatocellular carcinoma and cirrhosis, NAFLD has now become the leading cause of liver failure-associated transplantation. As a result of increasing microbiota studies with developing technological developments, the role of intestinal microbiota in the pathogenesis of NAFLD is revealed in an important way. In this study, it was aimed to determine the clinical prognostic importance of gut microbiota in the pathogenesis of NAFLD and to determine the microbial composition in NAFLD patients. We included 20 patients diagnosed with NAFLD as a result of various tests and 20 normal control groups, as well as laboratory data parameters of all individuals to use in this study. Written informed consent obtained from the individuals, after the ethics board approval had documented for this study. The healthy control group of the same age and gender as the patients were determined to be equal, and the age, gender, BMI, insulin resistance, AST, ALT levels of the individuals were recorded for analysis. Colonic mucosal biopsy samples were taken from the individuals included in the study under sterile conditions. Microbial results were obtained as a result of 16S rRNA gene metagenomic processes. The analysis of the recorded parameters was done with the SPSS.19 statistical program. In the designed study, 16 phylum, 28 class, 56 ordo, 128 family, 415 genus, 1041 species microorganisms were analyzed taxonomically in a total of 40 individuals. In our study, Intestinal microbial diversity is lower in NAFLD patients compared to control group individuals. In addition, gram-negative bacteria were found to be more dominant in NAFLD patients. As a phylum, Proteobacteria increased in NAFLD group, Bacteroidetes and Actinobacteria in control group, while Firmicutes had equal distribution in both groups. BMI OR=6.37, 95%CI (0.39-0.40) p value was 0.001 in laboratory data, whereas Proteobacteria OR=1.754, 95% CI (0.901-3.416), p value 0.05 in microbial profile. The 16S rRNA metagenomic study of intestinal microbiota using colonic mucosal biopsy samples in NAFLD disease was the first study in the Turkish population, and important data were obtained for other studies. In the data obtained, we think that Ruminococcaceae, Escherichia coli and Bacilli species, which increase in colonic mucosal epithelium in NAFLD patients, and Bacteroidetes, Actinobacteria and Enterococaceae species that decrease, will play an important active role in both diagnostic and treatment options.