The Effect Of Ultrasound Therapy On MMP-1 Of Rabbit Knee Osteoarthritis

Objective:Osteoarthritis(OA) is a common disease in the elderly people prone to articular cartilage degeneration, destruction and osteophyte formation in the pathological features of cartilage. Matrix metalloproteinases(MMPs) are considered in the OA disease process playing an important role. Matrix metalloproteinase-1, also be known as interstitial collagenase, is a subtype of matrix metalloproteinases and participate in collagen protein network break, proteoglycan degradation, also become the specific targets of reflecting the osteoarthritis disease level. It is hard to find in the normal cartilage, but in OA cartilage have increased significantly. Ultrasound is a mechanical wave, can promote cell proliferation, protein synthesis, stimulate collagen and cytokine production, can contribute to cartilage, ligaments and tendons and other tissue injury repair, the knee has obvious therapeutical effect. By observing the effect of rabbit knee cartilage gross morphological changes, pathological changes of cartilage cells, and the immunohistochemical expression of MMP-1, our subject want to research the repair effect and mechanism of rabbit knee cartilage cells with ultrasound therapy. Methods:(1) Research objects and intervention measures:The normal control group contains 10 rabbits which were randomly selected from 30 healthy New Zealand white rabbits, not modeling, the other 20 rabbits also were randomly divided into model group and the ultrasonic experimental group. Model group and the ultrasonic experimental group are using straight bit left knee plaster casts to create osteoarthritis. In the model group at 6 weeks were killed by air embolism method and cut knee. Then observe related indicators changes after modeling. In the remaining 10 rabbits,14 days after the Ultrasonic therapy were observed after treatment with the same change in relevant indicators. Ultrasonic therapy of knee joint take direct contact method, using a dose 3MHz frequency pulse type ultrasonic,0.25w/cm, once a day, every 10min, continuous treatment of 14 times. (2)Outcome measures:(DTo observe the left ultrasonic articular cartilage changes in gross morphology in the normal control group, model group and the experimental group with naked eye.②Resected condylus medialis tibiae of left knee cartilage,10% neutral formalin fixed After paraffin embedding, sections for light microscopy and HE staining and toluidine blue staining of cartilage morphology by manikin’s score.③Immunohistochemical analysis:using rabbit anti-MMP-1 kit to test left knee condylus medialis tibiae cartilage expression of MMP-1.(3)Statistical analysis were performed using Windows SPSS13.0.All numerical results are expressed with Means±S P<0.05 for the difference was significant. Results:(1) Cartilage general observation:the control group had no significant left knee joint effusion and synovial hyperplasia. The appearance of cartilage was smooth and blue white, color depth and bright, no cracks. Joint effusion and synovial proliferation articular surface rough, some parts appear erosion. All cartilage surface showed grayish yellow, lower gloss, surface slightly uneven and rough occurred on the left knee in Most of the model group rabbit. Ultrasonic therapy group, some animals appear synovial fluid and synovial hyperplasia. Cartilage erosion rough change the main, but to a lesser extent. (2)HE staining and toluidine blue staining pathological:In normal control group, HE staining showed cartilage surface of section smooth, uniform thickness of cartilage layer. Cartilage cells arranged regularly, cell size consistent with the full tide line; toluidine blue showed uniform, no loss of matrix staining; In model group, HE staining showed inflammation, superficial cartilage loss, cartilage thickness was singnificantly thinner, cartilage cells obviously reduced, a large number of clustered cells, tidal line disorder. Toluidine blue staining was diminished. In Ultrasound group, the rules of cartilage surface, cracks less than the neat arrangement of cartilage cells. Chondrocytes compared with the control group was significantly increased cartilage thickness larger than the model group, showing disorder tide line, a slight decline aniline blue staining. By manikin’s score the difference was significant (P<0.01). (3)Immunohistochemical determination of MMP-1:Normal group, only the surface of cartilage cells occasionally weak expression of MMP-1,for the little brown particles in cytoplasm. Model Group:cartilage matrix, the cytoplasm of both MMP-1 expression, the whole floor can be seen, especially in the table, the highest density the middle, more mature cartilage cells, brown to dark brown granules. Ultrasound treatment group: The surface cartilage chondrocytes scattered in the cytoplasm of MMP-1 expression exist, as a light tan particles. The difference was significant(P<0.01). Conclusions:(1)Using extension position with plaster cast model of fixed manufacturing osteoarthritis can simulate the pathogenesis of OA, and the experiment are successful. (2)MMP-1 has a degradation function of articular cartilage ECM, it is important influence on the increaseing cartilage degeneration and damage. (3)The ultrasonic treatment can effectively improve the rabbit knee OA, and its mechanism probably are connected with reducing cartilage MMP-1 levels, promoting the proteoglycan which will help repair cartilage cells, increase the content of cartilage matrix.