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

牙周韧带细胞被认为是机械应激的调节细胞，它应该能够将机械应激转换为生物信号，并被认为在自身机制的调控下表达一系列独特的基因，但有关机械应激反应的基因表达模式的细节仍不清楚。本研究利用基因芯片技术对机械应力刺激下的人PDL细胞中与机械应力相关的基因进行分析。1.压力的应用为了确定静态压力对PDL细胞的影响，将细胞包埋在三维胶原凝胶系统中，并在体内条件下进行Minic培养。通过在凝胶上放置一个塑料圆柱体来施加压缩力(机械应力)。2.机械应力相关基因的鉴定在基因芯片分析中，共鉴定出108个与机械应力相关的独立基因。其中85个基因在机械应力作用下表达上调，23个基因在机械应力作用下表达下调。在本研究中，我们首先建立了模拟体内条件的三维胶原凝胶细胞培养系统，以确定在静态压力下PDL细胞的基因表达谱。其次，我们尝试利用基因芯片技术来鉴定PDL细胞对机械应力的反应基因图谱。表达了与机械应力相关的新的有趣的基因，也发现了功能不清楚的基因。对其生理功能的进一步研究有助于阐明牙周组织在牙齿移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.