Identification and mechanical analysis of the factor from human periodontal ligaments with bone remodeling by tooth movement

PDL （periodontal ligament）细胞被认为是机械应力的调节细胞，应该能够将机械应力传递给生物信号，并被认为在其自身机制的调控下表达了一组独特的基因，但对机械应力响应的基因表达模式的细节尚不清楚。在本研究中，为了鉴定人PDL细胞中机械应力相关基因，采用cDNA微阵列分析方法检测了机械应力刺激下PDL细胞中基因的差异表达水平。为了确定静态压缩力对PDL细胞的影响，我们将细胞包埋培养在三维胶原凝胶体系中模拟体内条件。压缩力（机械应力）通过使用放置在凝胶上的塑料圆柱体施加。2.不加重量的凝胶作为对照。通过基因芯片分析，鉴定出108个与机械应力相关的独立基因。其中，85个基因被机械胁迫上调，23个基因被下调。在本研究中，我们首先建立了类似于体内条件的三维胶原凝胶细胞培养系统，以确定PDL细胞中受静态压缩力调节的基因谱。其次，我们试图利用cDNA微阵列技术确定PDL细胞中响应机械应力的基因谱。表达了与机械应力相关的新颖而有趣的基因，并发现了功能不明确的基因。进一步研究它们的生理作用有助于阐明牙周组织在牙齿运动过程中的作用机制。

PDL (periodontal ligament) cells are recognized as regulation of mechanical stress that should be able to exchange the mechanical stress to the biological signaling and thought to express a set of unique genes under the regulation of their own mechanism, but details of the gene expression pattern in response to mechanical stress is still unclear. In this study, to identify mechanical stress-related genes in human PDL cells, the differential expression level of genes in PDL cells stimulated by mechanical stress was examined using cDNA microarray analysis.1.Application of compressive forceIn order to determine the effect of static compressive force on the PDL cells, cells were embedded and cultured in a three-dimensional collagen gel system to minic in vivo conditions. Compressive forces (mechanical stress) were applied by the use of a plastic cylinder placed over the gels. The gels without the weight loading served as control.2.Identification of genes in response to mechanical stress by the cDNA microarray analysisIn the microarray analysis, 108 independent genes related to mechanical stress were identified. Among them, 85 genes were up-regulated by mechanical stress, on the other hand, 23 genes were down-regulated.In this study, first we developed the three-dimensional collagen gel cell culture system that resembles in vivo condition to determine the gene profile regulated by a static compressive force in PDL cells. Secondary, we attempted to dentify the gene profiles in response to mechanical stress in PDL cells using cDNA microarray technology. Novel and interesting genes related to mechanical stress were expressed, and also found the genes in which the function is unclear. Further studies on their physiological roles may contribute to clarify the mechanism of periodontal tissue during tooth movement.