[Changes in the expression of Dlx5, Msx2, and Dlx5/Msx2 in hPDLSCs loaded with cyclic tensile stress].

OBJECTIVE: To investigate the changes in the expression of Dlx5 and Msx2 in human periodontal ligament stem cells (hPDLSCs) loaded with cyclic tensile stress. METHODS: hPDLSCs were subjected to cyclic tensile stress (0.5 Hz, 3000 microm strain) for 3, 6, 12, 24 h through a four-point bending strain system. The expressions of Dlx5 and Msx2 mRNA were determined by real time PCR. RESULTS: Strong expressions of Dlx5 and Msx2 were found in the periodontal fibroblasts of the tension side 20 minutes after mechanical loading. The expression of Dlx5 mRNA decreased over time with the stress. The expression of Msx2 mRNA increased over time with the stress. CONCLUSION: Both Dlx5 and Msx2 are sensitive to mechanical stress. Cyclic tensile stress may induce differentiating of hPDLSCs towards mineralized tissue cells by promoting Dlx5 mRNA expression and decreasing Msx2 expression.