Effects Of Aerobic Exercise On Serum COMP And INOS In Articular Cartilage Of Rabbits With Knee Osteoarthritis

Objective:To study the effect of aerobic exercise with different intensities on rabbit with knee osteoarthritis, and the effect on serum cartilage oligomeric matric protein (COMP) and induction nitric oxide synthase (iNOS) in articular cartilage.Methods:Twenty healthy adult rabbits were chosen in this study. All the rabbits practice running for one week. Five ones were randomly selected as the blank control group (group A). The other15ones were duplicated into the models of osteoarthritis (OA) through intraarticular papain injections. After the success of the model, according to the former method subjects were randomly divided into model control group (group B), low intensity exercise group (group C), moderate intensity exercise group (group D). Rabbits in group C (0.5km/h,20min, three times/week) and group D (1.5km/h,20min, five times/week) received treadmill running programs with low or moderate intensity for4weeks, then stay freely in cages for4weeks, while group A and B stay freely in cages for8weeks. Observational index:the morphology changes of articular cartilage, haematoxylin-eosin staining, the mankin’s scores of cartilage, the levels of serum COMP and iNOS in articular cartilage. Statistical analysis was done via SPSS17.0software.Results:1. The pathological changes:The Mankin’s scores of articular cartilage in group B, C and D were significantly higher than that in group A (6.4±1.14,5.0±1.00,4.2±0.84vs0.6±0.55), which had statistical significance (P<0.05). Compared with group B, the Mankin’s scores of articular cartilage in group C and group D were lower, and the differences between them were statistically significant (P<0.05). But the difference between group C and group D was not statistically significant (P>0.05). 2. The integrated optical density (IOD) of iNOS:The levels of iNOS in group B, C and D were significantly higher than that in group A(24873±15212,8190±4309,7023±5571vs1243±1779), which had statistical significance (P<0.05). Compared with group B, the levels of iNOS in group C and group D were lower, and the differences between them were statistically significant (P<0.05). But the difference between group C and group D was not statistically significant (P>0.05).3. The levels of serum COMP:The levels of serum COMP in groupB, C and D were significantly higher than that in group A (133.65±28.74ng/ml,53.88±18.46ng/ml,50.84±18.97ng/ml vs19.94±4.99ng/ml), which had statistical significance (P<0.05). Compared with group B, the levels of serum COMP in group C and group D were lower, and the differences between them were statistically significant (P<0.05). But the difference between group C and group D was not statistically significant (P>0.05).4. The levels of serum COMP had positive correlation with Mankin’s scores (r=0.744, P<0.001).Conclusions:1. The levels of iNOS and COMP increased in the OA model, and the levels of serum COMP had positive correlation with the cartilage degeneration.2. Both low intensity aerobic exercise and moderate intensity aerobic exercise could improve the repair of injury articular cartilages; the therapy effects may be achieved by lowering the expressions of iNOS and COMP.