Study On Chondrocyte Apoptosis Of Osteoarthritis Cartilage

Apoptosis represents a physiologic form of cell death that is widely present in most living cells. Cell death is an essential event in the growth, development, and tissue homeostasis of multicellular organisms. A disturbance of delicate balance between cell survial and apoptosis has been implicated in the pathogenesis of a variety of human diseases.Osteoarthritis (OA) is a degenerative joint disease that is characterized by articular cartilage degradation. Most current conscepts on the pathogenesis of cartilage degradation are focused on the enzymatic degradation of the extracellular matrix and the suppression of new matrix synthesis. Matrix is mainly synthesised by chondrocytes. Some data indicated that the pathogenesis of OA is related to the disorder of chondrocyte apoptosis.To determine the occurrence of chondrocyte apoptosis in human OA cartilage, 9 OA patients and 6 normal controls were included. TUNEL technique was used to study apoptosis in situ. The OA cartilage had a higher proportion of apoptotic chondrocytes than that in normal controls (4-14% versus 0-2%). Apoptotic cells were located in the superficial, middle, and higher column zone of OA articular cartilage. The proliferative response of chondrocytes in OA was connected with apoptosis. Electron micrographs showed the morphological changes associated with apoptosis. bax and bcl-2 mRNA were detected by reverse transcriptase/polymerase chain reaction (RT-PCR), mRNA for bax and bcl-2 was detectable in chondrocytes of both OA and normal cartilage.The bax mRNA of Chondrocytes from patients with OA was over expressed to compare with the normal controls (P<0.01), OA cartilage chondrocyte...