Association of HMGB1 levels in synovial fluid with the severity of temporomandibular joint osteoarthritis.

BACKGROUND: HMGB1 usually serves as a damage-associated molecular pattern (DAMP) molecule (also known as alarmin) that regulates the inflammatory and immune responses via different receptors or direct uptake. Numerous studies have reported the association between HMGB1 and inflammatory diseases; however, its role in temporomandibular joint (TMJ) osteoarthritis (OA) has not been elucidated. In this retrospective study, we aimed to investigate HMGB1 levels in the synovial fluid (SF) in patients with TMJOA and TMID, their correlation with TMJOA and TMID severity, and the therapeutic effect of sodium hyaluronate (hyaluronic acid, HA) on TMJOA. METHODS: SF samples were analyzed for 30 patients with TMJ internal derangement (TMJID) and TMJOA, along with visual analog scale (VAS) scores, radiographic stages, and mandibular functional limitations. The SF levels of HMGB1, IL-1ß, IL-18, PGE2, RAGE, TLR4, and iNOS were determined via an enzyme-linked immunosorbent assay. To evaluate the therapeutic effects of HA, pre-treatment and post-treatment clinical symptoms were also compared in patients of the TMJOA group who had received an intra-articular injection of HA. RESULTS: VAS and Jaw Functional Limitation Scale (JFLS) scores were significantly higher in the TMJOA group than in the TMNID group, as were SF levels of HMGB1, TLR4, IL-1ß, IL-18, PGE2, and iNOS. The synovial HMGB1 level was positively correlated with the VAS score (r = 0.5512, p = 0.0016) and mandibular functional limitations (r = 0.4684, p = 0.0054). The cut-off value for the HMGB1 level as a diagnostic biomarker was 986.8 pg/ml. The SF level of HMGB1 yielded an area under the curve value (AUC) of 0.8344 for predicting TMJOA. HA alleviated TMJ disorders by significantly reducing the VAS score and improving the maximum extent of mouth opening in both the TMJID and TMJOA groups (p < 0.05). Moreover, patients in both the TMJID and TMJOA groups exhibited significant improvement in the JFLS score following HA treatment. CONCLUSIONS: Our results indicate that HMGB1 is a potential marker for predicting the severity of TMJOA. Intra-articular HA injection exerts a positive therapeutic effect on TMJOA; however, further investigations are warranted to validate its therapeutic effect in the late phase of visco-supplementation treatment.

Biofunctional Extracellular Matrix-Polycaprolactone-Hydroxyapatite Scaffold and Synovium Mesenchymal Stem Cells/Chondrocytes for Repairing Cartilage Defects.

Articular cartilage defects and degeneration can be caused by multiple factors, and the current clinical treatment schemes for pathological changes are relatively limited. Engineered cartilage tissue represents an alternative therapy for repairing cartilage defects in regenerative medicine. The scaffold material is considered the framework of tissue engineering; thus, scaffold material selection plays a crucial role in the therapy outcome. Polycaprolactone (PCL)-hydroxyapatite (HA) has been applied as a scaffold material for bone and cartilage tissue engineering with nontoxic, harmless metabolites and proper physical properties. The extracellular matrix (ECM) is mainly composed of collagen and proteoglycan, as well as a large number of growth factors and cytokines, which provide a tissue-specific microenvironment for host cells. Adipose-derived stem cells are pluripotent stem cells, and transforming growth factor-ß3 (TGF-ß3) enables mesenchymal stem cells to promote ECM production. This study, via in vitro and in vivo experiments, elucidated that the synovium mesenchymal stem cells (SMSCs) + chondrocytes + ECM-PCL-HA repair system, which is constructed upon the ECM-PCL-HA scaffold material, exhibits an adequate chondrogenic ability and reparatory effect. Overall, ECM-PCL-HA can be defined as a biofunctional scaffold material. The SMSCs + chondrocytes + ECM-PCL-HA repair system showed good confluency between the new cartilage and the surface, as well as the interface of the adjacent host cartilage. Furthermore, the structure of new cartilage tissue is consistent with adjacency. Thus, it can be used as a preferred plan for articular cartilage defect repair. Impact statement Studies investigating the chondrogenic ability and reparatory effect of the synovium mesenchymal stem cells (SMSCs) + chondrocytes + extracellular matrix (ECM)-polycaprolactone (PCL)-hydroxyapatite (HA) repair system provided a theoretical and practical basis for choosing ECM-PCL-HA as the scaffold material for cartilage tissue engineering. In this study, the transforming growth factor-ß3 (TGF-ß3) gene was introduced into adipose-derived stem cells (ADSCs) using a lentiviral vector to enhance ECM production. The decellularized ADSCs-ECM-PCL-HA acted as a biofunctional scaffold material with suitable physicochemical properties, which was advantageous for SMSC and chondrocyte adhesion and growth. Lastly, the SMSCs + chondrocytes + ECM-PCL-HA repair system showed excellent capability in the flush fusion state of the prosthetic surface and interface.

[Logistic regression analysis of risk factors of temporomandibular disorder in undergraduates of Xinjiang Medical University].

PURPOSE: To investigate the prevalence of temporomandibular disorders (TMD) in undergraduates of Xinjiang Medical University and analyse its possible risk factors. METHODS: A sample of 700 medical students included 244 males and 456 females was selected from Xinjiang Medical University and underwent examination of temporomandibular joint, questionnaire survey. Their average age was 20.08±1.457 years. Prevalence of TMD was analyzed, and the possible risk factors associated with the disease were identified by logistic regression analysis with SPSS17.0 software package. RESULTS: The prevalence of TMD was 42.40% in this population. There was no difference between different ethnics. Chewing-side preference, bruxism，orthodontic treatment，tooth extraction，psychological factors，anterior overjet, posterior scissors-bite were the main risk factors which increased the occurrence of TMD. CONCLUSIONS: Poor oral habits, psychological factors and malocclusion were related to the development of TMD.