Abstract

Rheumatoid arthritis (RA) and ankylosing spondylitis (AS) are two common rheumatic disorders marked by persistent inflammatory joint disease. Patients with RA have osteodestructive symptoms, but those with AS have osteoproliferative manifestations. Ligaments, joints, tendons, bones, and muscles are all affected by rheumatic disorders. In recent years, many epigenetic factors contributing to the pathogenesis of rheumatoid disorders have been studied. MicroRNAs (miRNAs) are small, non-coding RNA molecules implicated as potential therapeutic targets or biomarkers in rheumatic diseases. MiRNAs play a critical role in the modulation of bone homeostasis and joint remodeling by controlling fibroblast-like synoviocytes (FLSs), chondrocytes, and osteocytes. Several miRNAs have been shown to be dysregulated in rheumatic diseases, including miR-10a, 16, 17, 18a, 19, 20a, 21, 27a, 29a, 34a, 103a, 125b, 132, 137, 143, 145, 146a, 155, 192, 203, 221, 222, 301a, 346, and 548a.The major molecular pathways governed by miRNAs in these cells are Wnt, bone-morphogenic protein (BMP), nuclear factor (NF)-kappa B, receptor activator of NF-kappa B (RANK)-RANK ligand (RANKL), and macrophage colony-stimulating factor (M-CSF) receptor pathway. This review aimed to provide an overview of the most important signaling pathways controlled by miRNAs in rheumatic diseases.