MicroRNAs (miRNAs) are classes of non-coding RNA that function as negative regulators of protein-coding
gene expression at the post-transcription level. It has been elucidated that the miRNAs play a critical role in a variety of
human disease including arthritic diseases such as Rheumatoid arthritis (RA) and Osteoarthritis (OA).
RA is a chronic autoimmune disease mainly characterized by the inflammation of synovial tissue that leads to destruction
of the joint tissues, bone and cartilage. OA is characterized by the progressive destruction of articular cartilage. Recent
studies elucidated that several miRNAs are abnormally expressed in RA and OA, and some of these intimately involved in
The present review summarizes the current progress of miRNA synthesis and function, their expression and function in
arthritis, especially focused on the well investigated miRNAs, miR-146a and miR-155.