Upregulated ox40l Can Be Inhibited by miR-146a-5p in Condylar Chondrocytes Induced by IL-1ß and TNF-α: A Possible Regulatory Mechanism in Osteoarthritis.

INTRODUCTION: Osteoarthritis (OA) is a common musculoskeletal disease characterized by pain, stiffness, limited activity, occasional effusion, and local inflammation. MiR-146 is one of the noncoding RNA closely related to OA, but the role of miR-146 in OA remains controversial. The tumour necrosis factor receptor OX40 is activated by its cognate ligand OX40L (TNFSF4) and functions as a T-cell costimulatory molecule. The T-cell functions, including cytokine production, expansion, and survival, are enhanced by the OX40 costimulatory signals. METHODS: We established an inflammatory model of condylar chondrocytes induced by IL-1ß and TNF-α and detected the expression of miRNA by miRNA sequencing. Then, cell transfection was used to study the role of miR146a-5p in OA. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and database analysis were used to screen out potential target genes of miR-146a-5p. A dual luciferase activity assay tested whether ox40l is the target gene of miR-146a-5p. RESULTS: MiR-146a-5p and OX40L was upregulated after induced by IL-1ß and TNF-α, miR-146a-5p reduced the production of inflammatory factors but had no effect on chondrophenotypic factors, and ox40l was targeted by miR-146a-5p. CONCLUSION: OX40L and miR-146a-5p of condylar chondrocytes in the inflammatory environment (induced by IL-1ß and TNF-α) were significantly increased, miR-146a-5p is a protective factor in the inflammatory response, which can reduce the production of inflammatory factors, and miR-146a-5p may regulate T-cell-mediated immunity through targeting of ox40l in OA.

[Treated dentin matrix enhances proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells].

OBJECTIVE: The effect of treated dentin matrix (TDM) to the proliferation and osteogenesis differentiation of bone marrow mesenchymal stem cells (BMSCs) is evaluated in vitro. METHODS: TDM leaching solution was prepared by dentine particles suffering from gradient demineralization. Human BMSCs were isolated and cultivated, and subsequently cultivated in the TDM leaching solution. The proliferation of BMSCs was detected by CCK-8. The osteogenesis-related proteins, including collagen type I (Col I) and runt-related transcription factor-2 (Runx2), were extracted and detected by Western blot after a 7-day culture. RESULTS: Compared with the control group and hydroxyapatite (HA)/ß-tricalcium phosphate (ßTCP) group, the proliferation of BMSCs cultivated in TDM leaching solution was significantly improved. The expression of Col I and Runx2 obviously increased after the 7-day cultivation in TDM leaching solution. CONCLUSION: TDM can promote the proliferation and osteogenesis differentiation of BMSCs, implying the feasibility of the application in bone tissue engineering.

Treated dentin matrix enhances proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The effect of treated dentin matrix (TDM) to the proliferation and osteogenesis differentiation of bone marrow mesenchymal stem cells (BMSCs) is evaluated in vitro.</p><p><b>METHODS</b>TDM leaching solution was prepared by dentine particles suffering from gradient demineralization. Human BMSCs were isolated and cultivated, and subsequently cultivated in the TDM leaching solution. The proliferation of BMSCs was detected by CCK-8. The osteogenesis-related proteins, including collagen type I (Col I) and runt-related transcription factor-2 (Runx2), were extracted and detected by Western blot after a 7-day culture.</p><p><b>RESULTS</b>Compared with the control group and hydroxyapatite (HA)/β-tricalcium phosphate (βTCP) group, the proliferation of BMSCs cultivated in TDM leaching solution was significantly improved. The expression of Col I and Runx2 obviously increased after the 7-day cultivation in TDM leaching solution.</p><p><b>CONCLUSION</b>TDM can promote the proliferation and osteogenesis differentiation of BMSCs, implying the feasibility of the application in bone tissue engineering.</p>