Fig. 6

Deregulated miRNAs in RA affect osteoclastogenesis. Gross disturbances in skeletal structure and function in synovial joints of patients with RA are mostly the result of an imbalance in osteoclast-mediated bone remodeling. The discovery of RANKL signaling was indispensable for an in-depth understanding of the mechanisms underlying osteoclastogenesis and bone resorption. Dysregulated miRNA expression in RA, driven by the osteoimmune microenvironment, is capable of controlling the differentiation and maturation of osteoclasts through RANKL-dependent (left) and RANKL-independent (right) pathways, resulting in a progressive reduction in periarticular bone mass and subsequent bone erosion. miRNA microRNA, RA rheumatoid arthritis, RANKL receptor activator of nuclear factor-kappa B ligand