The Effect Of Mangiferin On Temporomandibular Joint Osteoarthritis

To investigate the role of mangiferin (MG) in the treatment of temporomandibular joint osteoarthritis (TMJOA) and clarify whether autophagy and SIRT1/mTOR pathway participate in MG treating TMJOA. In-vivo TMJOA model was generated by subjecting intra-articular injection of sodium monoiodoacetate (MIA). The rats (n=8/group) were divided into control (sham); TMJ OA; TMJ OA+MG groups. When investigating the effect of SIRT1, a parallel experiment containing TMJ OA+MG+EX-527 group was performed. Condyles of each group were subjected to micro-CT imaging analysis and were stained with haematoxylin-eosin, Masson and Safranin O Fast Green. In-vitro TMJOA model was generated by treating ATDC5 cells with interleukin (IL) -1β. Cells were divided into control, TMJOA, TMJOA+MG, TMJOA+MG+chloroquine (CQ) and TMJOA+MG+EX-527 groups. Inflammatory response, degradation of extracellular matrix, cell apoptosis, cell autophagy and SIRT1/mTOR signaling were detected by qRT-PCR, Western blot and Annexin V-FITC/PI assay. Micro-CT and tissue staining revealed thicker condylar cartilage, more regular formation of bone trabecula and cartilage, higher numbers of chondrocytes and proteoglycan in cartilage matrix and lower modified Mankin score after MG treatment. In-vitro experiments displayed a lower level of inflammatory response, degradation of ECM and cell apoptosis, while the level of cell autophagy and SIRT1 signaling were upregulated after MG treatment. These effects could be partially reversed by adding CQ and EX-527. Mangiferin is effective in treating TMJOA by enhancing chondrocyte autophagy via SIRT1/mTOR signaling pathway.