Expression of MMPs and the Effects of the Intervention of Calcitonin in Rat Osteoarthritis Cartilage
|Keywords||Rat Osteoarthritis MMPs Calcitonin|
Objective: To study the characteristics of the expression of matrix metalloproteinase (MMPs)-1、13 in chondrocyte in the process of Osteoarthritis (OA), and the effect after the intervention of Calcitonin (CT) .Methods: 55 SD rats were randomly divided into three groups, of which Surgery group and CT intervened group both consisted 25 rats, while non-surgery group consisted 5. Surgery Group and CT intervened Group were intervened by cutting off the anterior cruciate ligament and the medial meniscus of their right knees, while the left knees as the control samples. For the non-surgery group, we did not deal with the cruciate ligaments and meniscus, but only exposed the knee joint cavity. CT intervened Group were subcutaneous injected with CT 15IU/kg every other day from the second day of the surgery. The rats of CT intervened Group and Surgery Group were executed and the samples were extracted at 1,2,4,6 and 10 weeks after the surgery with 5 rats each time. Non-surgery group rats were executed at 10 weeks after joint exposion. Specimen’s general and histological sections were observed. Both sides of the knee cartilage specimens were carried out within the MMP-1、MMP-13 expression detection by ELISA.Results: The model of Group ACLT+MMx can be seen the histological changes 1 week after surgery; after 2 weeks the general observation of cartilage surface appears dull; after 4weeks the formation of osteophyte were shown; after 10weeks the defection of cartilage can be seen with exposion of subchondral bone. It is witnessed the development of Mankin score from 1 week of 1.0 to 4 weeks to 10weeks of 6.2 points to 13.6 points. It were significantly different compared with the non-operated group. The expression of MMP-13 of the knee cartilage cells of Group ACLT+MMx increased early and inhibited remarkablely in the later stage. The expression of MMP-1 was correlated with the severity of diseases. After using the intervention of Calcitonin, the expression of MMP-1 and MMP-13 was decreased,compared of Group ACLT+MMx in the same time.Along with the progress of the disease, the overall trend is similar with Group ACLT+MMx.Conclusion: The resection of anterior cruciate ligament and medial meniscectomy can effectively produce rat OA model. The expression of MMPs in OA process of chondrocyte, of which MMP-13 first increased, then decreased, the trend of expression of MMP-1 was correlated with the disease severity. Calcitonin not only cut MMPs expression in a certain period but also improved OA symptoms. It means that Calcitonin could delay osteoarthritis process in a certain extent.