Dependence of Intestinal Microbiota Composition on Distribution and Activity of Adipose Tissue in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) pathogenesis displays a close relation with intestinal dysbiosis. Thus, the aim of this study was to investigate the intestinal microbiota (IM) composition and to determine the correlation of changes in its main phylotypes with the amount and activity of adipose tissue in NAFLD patients. Methods. The prospective study enrolled 114 NAFLD patients with metabolic disorders and 30 healthy subjects as the control group. Along with routine examination, the authors assessed intestinal microbiota composition by identifying total bacterial DNA and DNA of Bacteroidetes, Firmicutes, and Actinobacteria by means of a quantitative real-time PCR. Results. NAFLD patients showed a signifi cant decrease in the relative amount of Bacteroidetes with a simultaneous increase in the Firmicutes and an increase in Firmicutes/Bacteroidetes ratio compared with healthy subjects (p<0.05). NAFLD patients with concomitant overweight and obesity displayed a more significant imbalance of IM with an increase in the Firmicutes/Bacteroidetes ratio due to the inhibition of Bacteroidetes, compared with patients of normal body mass index. The revealed changes in the main phylotypes of IM in the examined patients were proven linked not only to an increase in body weight but also to the amount and activity of visceral adipose tissue. Furthermore, deviations in the gut microbiota composition had an impact on the formation and severity of steatosis. Conclusions. The study revealed an imbalance of IM in NAFLD patients. Further research in gut microbiota will help to elucidate their role in NAFLD pathogenesis and to lay a foundation for the development of individualized treatment.