Abstract: ObjectiveTo observe the effects of chitosan injected intra-articular on cartilage degeneration of rabbits with osteoarthritis(OA).MethodsOA animal model was established by unilateral anterior cruciate ligament transaction(ACLT) in 18 rabbits.After operation,animals were randomly divided into the experimental group and control group with 9 rabbits in each group.The experimental group was treated with intra-articular injection of 0.3 ml of 2% chitosan every two weeks after operation.While,the control group was injected with 0.3 ml normal saline at the same time.All rabbits were killed at the 8th week.Cartilage degradation of femoral condyles was evaluated at macroscopic level and the changes of proteoglycan of articular cartilage matrix were detected by biochemical technique,and the expression of matrix metalloproteinases-1(MMP-1) was documented by immunohistochemistry.ResultsCartilage degradation in the control group was significantly more severe than that in the experimental group in macroscopic grading scale(P<0.05).The detection of proteoglycan showed that the quantity of glycosaminoglycans increased(P<0.01) and the chondroitin sulfate/keretan sulfate declined(P<0.05) in experimental group compared with that in the control group.Immunohistochemistry study showed that the expression of MMP-1 in the control group was significantly more severe than that in the experimental group(P<0.01).ConclusionChitosan can prevent cartilage degaradation and protect cartilage.

Key words: chitosan, cartilage, osteoarthritis