Carboxymethyl Chitosan Bel - 2 In The Rabbit Knee Cartilage Degeneration And The Influence Of Caspase 3 Protein Expression

Objective：This study aims to investigate the changes of articular cartilage and cartilageprotein expression after injecting Carboxymethyl chitosan (CMCS) in rabbit kneejoint,and learn the influence of CMCS on articular cartilage.Method:Osteoarthritis (OA) was induced in knees of33rabbits by improved Hulthmethod. Choose3rabbits randomly as group D,killed in the4thweeks. The rest ofrabbits were randomly divided into3groups.[A:injection of0.3ml saline in right joint(n=10); B:injection0.3ml hyaluronic acid (HA) in right joint (n=10); C:injection0.3ml CMCS in right joint (n=10)]. HA is injecting once a week and CMCS isinjecting once two weeks. After6weeks,killed all the animals to observe the changesof general and pathological in the knee joint. Expression of bcl-2,caspase-3weredetected by immunohistochemistry, apoptosis of chondrocytes was observed byTUNEL.Result:Cartilage degradation in group A was significantly more severe than that ingroup B and group C both in macroscopic grading scale and microscopic changes.Group D showed little changes of Cartilage degradation.Markin scores is7.60±0.97in group A,6.30±0.48in group B,4.70±0.82ingroup C and3.30±0.57in group D (P<0.05between groups).The express of bcl-2was increased in group C than group A, B and C[(45.85±1.81)%vs (30.16±2.56)%;(45.85±1.81)%vs (36.86±1.94)%;(45.85±1.81)%vs（38.67±0.55）%; P<0.05respectively]. Caspase-3expression was lowest in group Cthan all other groups (P<0.05).The apoptosis rates of chondrocyte in group C were significantly lower thangroup A and B[(25.90±1.26)%vs (35.72±1.28)%;(25.90±1.26)%vs (30.53±1.51)%;P<0.05respectively]. Group D has the lowest apoptosis rates (21.57±0.97)%.In group C apoptosis rate of bcl-2correlated negatively with caspase-3 (r=-0.950，p<0.01).Conclusion:CMCS can improve the expression of bcl-2, and reduce the expression ofcaspase-3. CMCS can inhibit the apoptosis of chondrocytes and delay the process ofcartilage degeneration to protect the function of cartilage, it may be useful in thetreatment of arthritis.