Osteoarthritis (OA) is the most common form of arthritis. It results from an imbalance between predominantly chondrocyte-controlled anabolic and catabolic processes, and is characterized by progressive degradation of the components of the extracellular matrix (ECM) of the articular cartilage, associated with secondary inflammatory factors.

The effect of xanthones from mangosteen on the cartilage degradation in vitro and human chondrocyte culture was investigated. GM-1 was found to be the most active, comparable to or even better than the drugs presently prescribed for osteoarthritis. The detail of this findings together with the molecular mechanism and mode of action will be presented.