Histone deacetylase inhibitors attenuated interleukin-1β-induced chondrogenesis inhibition in synovium-derived mesenchymal stem cells of the temporomandibular joint

Aims In the repair of condylar cartilage injury, synovium-derived mesenchymal stem cells (SMSCs) migrate to an injured site and differentiate into cartilage. This study aimed to confirm that histone deacetylase (HDAC) inhibitors, which alleviate arthritis, can improve chondrogenesis inhibited by IL-1 beta, and to explore its mechanism. Methods SMSCs were isolated from synovium specimens of patients undergoing temporomandibular joint (TMJ) surgery. Chondrogenic differentiation potential of SMSCs was evaluated in vitro in the control, IL-1 beta stimulation, and 1L-1 beta stimulation with HDAC inhibitors groups. The effect of HDAC inhibitors on the synovium and condylar cartilage in a rat TMJ arthritis model was evaluated. Results Interleukin (IL)-1 beta inhibited the chondrogenic differentiation potential of SMSCs, while the HDAC inhibitors, suberoylanilide hydroxamic acid (SAHA) and panobinostat (LBH589), attenuated inhibition of IL-1 beta-induced SMSC chondrogenesis. Additionally, SAHA attenuated the destruction of condylar cartilage in rat TMJ arthritis model. IL-6 (p < 0.001) and matrix metalloproteinase 13 (MMP13) (p = 0.006) were significantly upregulated after IL-1 beta stimulation, while SAHA and LBH589 attenuated IL-6 and MMP13 expression, which was upregulated by IL-1 beta in vitro. Silencing of IL-6 significantly downregulated MMP13 expression and attenuated IL-1 beta-induced chondrogenesis inhibition of SMSCs. Conclusion HDAC inhibitors SAHA and LBH589 attenuated chondrogenesis inhibition of SMSC induced by IL-1 beta in TMJ, and inhibition of IL-6/MMP13 pathway activation contributes to this biological progress. This study provides a theoretical basis for the application of HDAC inhibitors in the treatment of TMJ arthritis.