[Intervention effect of Youguiwan on rats with knee osteoarthritis and its mechanism]

Objective: To study the effects of Youguiwan on the osteoglycin (OGN), osteonectin (ON), fibrinogen 2 (FBN2) of articular cartilage tissue in the model of knee osteoarthritis (KOA). Methods: Sixty SD rats were randomly divided into six groups: sham control group, model group, glucosamine sulfate group, Youguiwan (high-dose, middle-dose and low-dose )group. The modified Hulth method was used to establish KOA models for 6 weeks. The sham control group and the model group were treated with normal saline. The rats in Youguiwan high-dose, middle-dose, low-dose groups were treated with Youguiwan at the doses of 4.8, 2.4, 1.2 g/kg by gavage respectively, and the glucosamine sulfate group was treated with glucosamine sulfate 0.17 g/kg. The rats were administrated for 8 weeks according to the dose. After intervening, articular cartilage of rats were obtained, the pathological changes were observed by using HE staining method, and Mankin score was evaluated. The expressions of OGN, ON and FBN2 in articular cartilage were detected by immunohistochemistry. The expression of GSK-3β in articular cartilage was detected by Western blot. Results: Compared with the sham control group, the Mankin score was obviously increased in the model group, the protein expression of FBN2 was increased significantly, yet the protein expressions of OGN, ON and GSK-3β were decreased significantly (P＜0.01), articular cartilage was seriously damaged, and chondrocytes were arranged in disorder. Compared with the model group, the Mankin score was declined obviously in the high-dose Youguiwan group, the protein expression of FBN2 was significantly decreased, but the protein expression of GSK-3β was significantly increased, the protein expressions of OGN and ON were significantly increased in the middle-dose and high-dose Youguiwan group (P＜0.05 or P＜0.01), cartilage structure was tended to be normal, the chondrocytes distribution was uneven, and articular cartilage surface was not smooth. Conclusion: Youguiwan can significantly improve the articular cartilage degeneration of KOA rats, its mechanism maybe raise OGN and ON protein expression level to promote the ossification and reconstruction of articular cartilage.