| Objective: To study the therapeutic effect and mechanism of extracorporeal shock wave therapy (ESWT) on knee osteoarthritis (KOA) rat model. Methods: Totally, 44 rats were randomly divided into normal group, model group, drug group and shock wave group (11 in each group). KOA animal model was established in all rats except normal group. The drug group was given 1 mg/kg meloxicam, shock wave group received ESWT, normal group and model group were not interfered. The severity of knee joint injury was evaluated by Mankin score. Tenderness and heat pain threshold of rats were measured by tenderness meter and heat pain meter. Serum levels of tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), IL-9, matrix metalloproteinase 3 (MMP-3), MMP-9 and type II collagen were detected by ELISA. The morphology of articular cartilage was observed by HE staining. The expression levels of cysteinyl aspartate specific proteinase-1 (Caspase-1) and gasdermin-D (GSDMD) in synovial tis-sue were detected by Western blot. Results: Compared with normal group, Mankin score, TNF-α, IL-1β, IL-9, MMP-3, MMP-9, Caspase-1 and GSDMD protein expression in synovium tissue were increased in model group, drug group and shock wave group, and tenderness, heat pain threshold and type II collagen were decreased (P<0.05). Compared with model group, Mankin score, TNF-α, IL-1β, IL-9, MMP-3, MMP-9, Caspase-1 and GSDMD protein expression in synovium tissue were decreased in meloxicam group and shock wave group, the lowest in shock wave group (P<0.05), tenderness, heat pain threshold and type II collagen were increased, and the highest in shock wave group (P<0.05). The cell arrangement of the model group was obviously abnormal, and a large number of inflammatory infiltrates could be seen between cells. The articular cartilage morphology was significantly improved in the meloxicam group and the shock wave group, and the inflammatory infiltration between cells was reduced, and the shock wave group tended to be normal. Conclusion: ESWT can reduce the Mankin score, tenderness and heat pain threshold of KOA rats, inhibit the release of MMP-3, MMP-9, Caspase-1, GSDMD protein expression and inflammatory response, and promote the synthesis of type II collagen, which is conducive to improving the knee joint morphology of KOA rats and improving the short-term effect of KOA treatment. |
