Pathogenetic and Epigenetic Aspects of the Co-Occurrence of Rheumatoid Arthritis and Liver Diseases

Abstract

Purpose: to determine the pathogenetic aspects expression-rate of miRNAs 122 and 221 in the serum of sufferers with rheumatoid arthritis (RA) as serum biomarkers associated with the causes of liver damage in this type of patients. Methods: MicroRNAs 122 and 221 (miRNA122/221) were isolated from peripheral blood samples of a total of 148 patients diagnosed with RA (17 patients with RA and chronic viral hepatitis B and C (СHB and C) in the 1st subgroup, 45 patients with RA and non-alcoholic fatty disease liver (NAFLD) in the 2nd subgroup and in the 3rd subgroup, 86 patients were diagnosed with RA without primary concomitant liver diseases), and their expression levels were determined using real-time reverse transcription polymerase chain reaction (PCR). Aspects of the results related to the pathogenesis of pathological conditions were then analyzed and their correlation with other signs of liver function was established. Results: The expression level of miRNA122 in sufferers with diagnosis RA and chronic hepatitis was significantly lower compared to patients in groups 2 and 3, and the expression level of miRNA221, on the contrary, was higher than in patients of other groups (p = 0,005). In addition, the expression degree of miRNA221 in patients with both RA and NAFLD was slightly higher than in patients of the three groups, and the difference was statistically significant (p = 0,005). The degrees of miR 221 were found correlated with fibrotic changes in liver tissue, and the expression-rate of miR 122 were found to significantly correlate with ALT (p < 0,005) and AST (p < 0,001). Conclusions: From the research results, we can conclude that complex correlations of microRNA 122/221 expression with RA and diffuse liver diseases have been identified, which may be a promising marker of RA and liver pathologies.