Outlines of the biochemistry of osteoarthritis

Osteoarthritis (OA) is a complex, age dependent disease in which various factors, including metabolic changes, are all major contributors to its onset and progression. Anatomically, OA embraces the whole joint, i.e. articular cartilage, subchondral bone alterations and joint-lining synovial membrane. Correspondingly, OA development involves elaborate interactions of cartilaginous tissue metabolism and maintenance, osteogenesis, mineralization and inflammation of the synovial membrane. Identification of the molecular pathways and individual factors involved in OA etiology, understanding of mechanisms of their action and interaction are necessary conditions for developing the accurate diagnostic and prognostic tools and for providing OA patients effective treatment. There is a major progress in understanding of the molecular mechanisms of OA appearance and progression, which are pointing out to the network of biochemical factors important for normal functioning of the joints and changes leading to OA. The present review summarizes the data on the efficacy of the relevant biochemical factors affecting all the components of the joint and that could be therefore useful targets in treatment of OA. However, despite the dramatic growth of the knowledge concerning the biochemistry of OA and discovery of a number of useful biomarkers the real breakthrough in this area is still not achieved.