Abstract:Objective: To compare the the effects of Ermiao Fang (EM) with different medicinal guides in osteoarthritis(OA) rats, and explore the related mechanism. Method: Sixty male Sprague-Dawley rats were randomly divided into sham-operated, model, EM (1.6 g·kg-1·d-1), EM plus Angelicae Pubescentis Radix (1.6 g·kg-1·d-1+0.3 g·kg-1·d-1) and EM plus Asari Radix et Rhizoma (1.6 g·kg-1·d-1+0.3 g·kg-1·d-1), evenly 12 in each group. Except the sham group, underwent surgical destabilization (anterior cruciate ligament transection and partial medial meniscectomy) of the right knee to induce OA.Meanwhile distilled water and corresponding drugs were administrated by gavage respectively, and materials were drawn at the third and sixth week. To observe the histopathological changes of knee articular cartilage and synovium by HE staining. And Chondrocytes apoptosis was tested by TUNEL assay. Matrix metalloproteinase-13 (MMP-13) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were measured by immunohistochemical assay. Interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), nitric oxide (NO) and inducible nitric oxide synthase (iNOS) in serum were detected by ELISA or radioimmunoassay. Result: Compared with the sham group, the pathological score of articular cartilage and synovium and the chondrocytes apoptosis rate in the model guoup were higher (P<0.01), and it was decreased MMP-13 and augmented TIMP-1 expression in the cartilage, and the levels of IL-1β, TNF-α, NO and iNOS in serum were rised. Compared with the model group, the EM could obviously improve the articular cartilage andsynovial lesions, reduce the apoptosis of cartilage cells, and reduce the level of TNF-α in serum at the third week. At the sixth week, it obviously decreased MMP-13 and augmented TIMP-1 expression in the cartilage, inhibited release of IL-1β, NO and iNOS. Compared with the EM group, the medicinal guide groups could further improve the joint pathology, reduce the cartilage cell apoptosis (P<0.01), regulate the expression of MMP-13 and TIMP-1(P<0.05), and reduce the levels of the inflammatory cytokines. Especially at EM plus with Angelicae Pubescentis Radix group, it could significantly decrease the Makin score from the third week(P<0.05), and improve the inhibition levels of the synovium and IL-1β, TNF-α of the EM group at the sixth week. Conclusion: The EM could slow the pathological process in osteoarthritis rat model. Combined with Angelicae Pubescentis Radix or Asari Radix et Rhizoma, it could further improve the curative effect with different levels. Especially, the effect of Angelicae Pubescentis Radix was more remarkable. And the mechanism may be related with the reduction of chondrocytes apoptosis, the regulation of MMP-13 and TIMP-1 equilibrium and reducing the inflammatory cytokine.