ABSTRACT
Objective To explore the role of Notch signaling pathway in the matrix synthesis of osteoarthritis cartilage cell and its possi -ble mechanism.Methods Selected the femoral condylar cartilage of 8 patients who were admitted into our hospital and treated with knee joint replacement as the observation group,while the normal femoral condyle cartilage of one patient with above-knee amputation was selected as the control group.The specimens were given histological examination or cell isolation culture and detection.The cultured cells were divided into 4 groups,namely the normal cartilage cells,OA cartilage cells,OA cartilage cells with γ-secretase inhibitor DAPT,OA cartilage cells with recombinant human proteins Delta4.Then immunohistochemistry and Western blot were used for detecting the expression of Notch -1,Notch-3, Jagged-1,Jagged-2 and HES5 in chondrocytes in vitro.Results The expression of Notch signaling pathway and the phenotype of cartilage cells changed in the osteoarthritis.The expression of Notch-1,Jagged-1,Jagged-2 and HES5 were activated.γ-secretase inhibitor DAPT (20 μmol/L)could inhibit the expression of Notch-1,HES5,Jagged-1,and Notch-3,while it had no obvious effect on the expreesion of Jag-ged-2.Recombinant human proteins Delta 4(100 ng/μL)could promote the expression of Notch-1,Jagged-2,and HES5,and it had no obvi-ous effect on the expreesion of Jagged-1 and Notch-3.Conclusion The expression of Notch signaling pathway of cartilage cells changed in the osteoarthritis.DLL4 can activate the Notch signaling pathway and DAPT can inhibit the Notch signaling pathway.