Abstract: Objective: To investigate the expression of SIRT1 in the synovial of temporomandibular joint osteoarthritis(TMJ OA). Methods: HE staining was used to observe the synovial tissue morphology. Immunohistochemistry was used to detect the expression and distribution of SIRT1 in synovial tissue. The human TMJ synovial cells were cultured in vitro by tissue explantation. Western blotting and real-time PCR were used to detect the SIRT1 protein and gene expression in synovial cells. Results: HE staining showed that the synovial membrane of the OA group was significantly thicker than the normal group, and the blood vessels increased. Immunohistochemistry showed that the staining intensity of SIRT1 in the OA group was significantly higher than that in the normal group (P<0.05). Real-time PCR and Western blotting showed that the expression of SIRT1 in synovial cells of OA group was significantly higher than that of normal group (P<0.05). Conclusion: The expression of SIRT1 in the synovium of TMJ OA is closely related to the occurrence and development of osteoarthritis, providing a new theoretical basis for the molecular mechanism and treatment of this disease.

Key words: Temporomandibular joint osteoarthritis, Synovial tissue, Synovial cells, Silent information regulator 1