Wu Jiannan, Song Meng, Li Tengyu, Zhu Zhengxian, Pan Jinsong
Department of Stomatology, First People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Department of Stomatology, First People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Exp Cell Res. 2015 Sep 10;337(1):28-36. doi: 10.1016/j.yexcr.2015.07.016. Epub 2015 Jul 19.
Tooth movement is the result of periodontal tissue reconstruction. The biomechanical effects produced by orthopedic forces can affect the cytoskeletal rearrangement of human periodontal ligament cells (hPDLCs). However, the mechanisms responsible for the cytoskeletal rearrangement are not completely understood. To analyze the effect, we investigated the role of the Rho-mDia1 signaling pathway in cyclic strain-induced cytoskeletal rearrangement of hPDLCs in detail. We cultured hPDLCs on collagen I-coated six-well Bioflex plates and then exposed them to cyclic strain with physiological loading (10%) at a frequency of 0.1Hz for 6 or 24h using a Flexercell Tension Plus system. Notably, the cells cultured on the Bioflex plates showed increased expression levels of RhoA-GTP, profilin-1 protein, and the combination of RhoA and mDia1, whereas the expression levels of Rho-GDIa were reduced compared with a static control group. Furthermore, the cytoskeletal rearrangement of cells was enhanced. However, profilin-1 protein expression and cytoskeletal reorganization under cyclic strain can decrease due to the overexpression of Rho-GDIa or mDia1-siRNA transfection, whereas Rho-GDIa siRNA transfection has the opposite effect on hPDLCs. Together, our results demonstrate that the Rho-mDia1 signaling pathway is involved in the cytoskeletal rearrangement of hPDLCs induced by cyclic strain. These observations may enable a more in-depth understanding of orthodontic tooth movement and the reconstruction of PDL and alveolar bone.
牙齿移动是牙周组织重建的结果。正畸力产生的生物力学效应可影响人牙周膜细胞（hPDLCs）的细胞骨架重排。然而，细胞骨架重排的具体机制尚未完全明确。为分析其影响，我们详细研究了Rho-mDia1信号通路在周期性拉伸诱导的hPDLCs细胞骨架重排中的作用。我们将hPDLCs培养在I型胶原包被的六孔Bioflex板上，然后使用Flexercell Tension Plus系统，以0.1Hz的频率、10%的生理负荷对其施加周期性拉伸6小时或24小时。值得注意的是，与静态对照组相比，培养在Bioflex板上的细胞中RhoA-GTP、原肌球蛋白-1蛋白以及RhoA与mDia1的结合物表达水平升高，而Rho-GDIa的表达水平降低。此外，细胞的细胞骨架重排增强。然而，由于Rho-GDIa的过表达或mDia1-siRNA转染，周期性拉伸下原肌球蛋白-1蛋白的表达和细胞骨架重组会降低，而Rho-GDIa siRNA转染对hPDLCs则有相反的作用。总之，我们的结果表明Rho-mDia1信号通路参与了周期性拉伸诱导的hPDLCs细胞骨架重排。这些观察结果可能有助于更深入地理解正畸牙齿移动以及牙周膜和牙槽骨的重建。
