Serum levels of neurokinin B in patients with non-alcoholic fatty liver disease and intestinal lesions after COVID-19

Abstract

Background. The study of neuropeptides, including substance P, neurokinins, may reveal possible mechanisms of the progression of gastrointestinal lesions with the formation of motility disorders in patients with coronavirus disease 2019 (COVID-19), especially in metabolically associated diseases such as non-alcoholic fatty liver disease (NAFLD), obesity, type 2 diabetes mellitus. Aim of the research: to determine the peculiarities of changes in serum neurokinin B (NK-B) levels in patients with NAFLD after COVID-19. Materials and me­thods. The study included 104 patients with NAFLD and intestinal lesions at the outpatient stage of follow-up after COVID-19 (they formed the main group of those being treated (group I)). Group II (comparison one) included 78 patients with NAFLD who did not have neither COVID-19, nor complaints indicating intestinal lesions. All examined patients were tested for NK-B levels in blood serum. Results. Complaints indicating intestinal lesions in patients with NAFLD after COVID-19 were more often manifested by changes in the act of defecation, namely constipation was diagnosed in 51.0 % of cases (р < 0.001), a tendency to diarrhea — in 26.9 %, and in 22.1 % of patients in group I, constipation followed by diarrhea was diagnosed. Among NAFLD patients, a significant increase in serum NK-B levels with minimal deviations from the norm was found in group II (1.1-fold; р < 0.05), while in group I, significant deviations from the norm were diagnosed (3.0-fold; р < 0.001). The lowest levels of NK-B were detected in intestinal damage manifested by constipation. In patients with diarrhea in NAFLD after COVID-19, the level of NK-B was maximal and 6.2 times (р < 0.001) higher than that of the control group. Conclusions. Among patients with NAFLD, intestinal damage after COVID-19 is more often manifested by constipation (in 51.0 % of cases). In patients with NAFLD after COVID-19, changes in the level of neurokinin B in the blood serum were found, with its minimum in constipation ((0.173 ± 0.009) pg/ml; р < 0.01), and maximum values in patients with diarrhea (an increase to (1.782 ± 0.023) pg/ml; р < 0.001).