Growth, Differentiation And Apoptosis Of Chondrocyte From Arthritis And Normal Articular Cartilage

Arthritis is one of the most frequent, devastating and costly problems in human health care. The degeneration and the destruction of articular cartilage are the characteristic pathological feature of osteoarthritis (OA) and rheumatoid arthritis (RA). The pathophysiology of this cartilage destruction is of significant interest, due both to its potential role in the elucidation of normal cartilage metabolism and for its clinical potential in the treatment of these debilitating diseases. The articular cartilage is a high specialized tissue characterized by relatively small number of cells embedded in an avascular extracellular matrix produced and maintained by the chondrocytes. The growth, differentiation, development ,and the behavior .function of the chondrocytes during the OA, RA pathophysiology attract much more attention in the area of medical biology in recent years.Collagen is the major component of joint cartilage matrix and it not only determines the structure and the function of cartilage, but also different type collagens associated with the different differentiation stage and the cartilage degradative process of OA and RA. Chondrocyte differentiation is accompanied by a switch of gene activation: chondrogenic mesenchymal cells produce collagens I and III, whereas chondrocytes synthesize cartilage specific proteoglycans and collagens II, IX, XI. Hypertrophic chondrocytes also produce collagen X, a biochemical marker for this stage of cell differentiation. Usually, the stage is reached only in cartilage undergoing endochondral ossification during development, growth, or repair of bones. In permanent cartilage, e.g., normal articular cartilage close to the joint surface, terminal chondrocyte differentiation does not take place but is interrupted at the stage of resting chondrocyte. The chondrocytes in more advanced stages of OA and RA express...