Influence of psychotraumatic factors of the war period on the state of the intestinal microbiota and intestinal epithelial permeability in patients with non-alcoholic fatty liver disease

Objective — to determine the association between the degree of disruption of the intestinal epithelial barrier integrity by the level of zonulin, the state of the intestinal microbiota and biomarkers of stress in patients with non‑alcoholic fatty liver disease (NAFLD) in wartime conditions. Materials and methods. The study involved 88 patients with NAFLD with metabolic disorders, of which 57 during military operations (the main group), 31 in the pre‑war period (the comparison group). Anthropometric parameters, indicators of the functional state of the liver, carbohydrate metabolism and lipid metabolism were assessed using standard methods. The content of chronic stress hormones in the blood serum — brain‑derived neurotrophic factor, prolactin, dehydroepiandrosterone sulfate and the epithelial permeability marker zonulin was determined by solid‑phase enzyme‑linked immunosorbent assay. The relative composition of the main phylotypes of the intestinal microbiota was determined by quantitative real‑time polymerase chain reaction (qRT‑PCR) using universal primers for the 16S rRNA gene and taxon‑specific primers (Thermo Fisher Scientific). Statistical data processing was performed using the SPSS 17.0 statistical software package. Results. In patients with NAFLD, examined both in the pre‑war period and during the war, a statistically significant increase in zonulin levels was recorded. In patients examined before the start of hostilities, the concentration of zonulin exceeded the reference values by almost 2.6 times. After the start of the war, zonulin levels were recorded that were 3.7 times higher compared to the group of healthy individuals and 1.5 times higher compared to the group of patients with NAFLD, examined in the pre‑war period. In the main group, a statistically significant increase in the concentration of zonulin was found in obese patients compared to patients with normal and overweight body weight. When comparing zonulin levels with the main phyla of the intestinal microbiota, a direct correlation of medium degree with the content of Firmicutes was found in the group of patients with NAFLD examined during military operations. In the comparison group, a similar correlation was established, but of a lower degree. The relationship of zonulin levels with other bacterial phyla in both groups was not found. A direct correlation was established between the level of prolactin and the content of zonulin in patients with NAFLD of the main group, which indicates that prolactin can negatively affect intestinal permeability, stimulate the activation of metabolic disorders and inflammation and lead to disease progression. The maximum increase in zonulin content was noted in high‑grade steatosis. The level of zonulin both at the initial (F0‑F2) and at the advanced stages (F3‑F4) of liver tissue fibrosis was comparable in both examined groups regardless of the degree of fibrosis. Conclusions. In patients with NAFLD who were exposed to adverse factors of wartime, a statistically significant 1.5 times increase in the level of zonulin was found compared to the group of patients examined in the pre‑war period. Increased intestinal permeability was observed in patients with NAFLD of the main group with obesity, accompanied by high activity of visceral adipose tissue, an increase in the degree of steatosis. Stress hormones, in particular prolactin, can negatively affect changes in the intestinal microbiota and intestinal permeability, stimulate the activation of metabolic disorders and inflammation and lead to the progression of NAFLD.