REGULATION OF OSTEOCLASTIC BONE RESORPTION BY RHO

当机械力施加到牙齿上时，机械应力加载到牙周组织上。许多骨细胞位于骨基质中，通过细胞质过程和间隙连接相互沟通，以及与骨表面上的成骨细胞沟通。在本研究中，为了探讨骨细胞在骨吸收中的作用，我们研究了纯化的鸡骨细胞衍生蛋白（ODP）和Rho-GTP解离抑制剂（Rho-GDI）对骨吸收的影响。最近，我们建立了一个培养系统，提供了人成熟的破骨细胞从外周血单核细胞（PMBC），通过使用M-CSF和人可溶性RANKL（sRANKL）在缺乏成骨细胞和基质细胞。将FITC标记的α-辅肌动蛋白预先显微注射到人破骨细胞中， ...更多信息 合并成衬在细胞外围的足体。虽然在注射缓冲液后仍观察到足体，但微量注射ODP和Rho-GDI在注射后30 min内引起足体的破坏。此外，这两种蛋白质显着抑制小窝的形成，而骨细胞的条件培养基没有effect.This研究还集中在一个新的半胱氨酸蛋白酶，组织蛋白酶K，这是通过特异性表达在破骨细胞和骨细胞骨吸收中起着重要作用。我们通过检测组织蛋白酶K mRNA表达的变化与牙槽骨组织学的变化，研究了正畸牙齿移动过程中牙槽骨改建的机制，进一步了解破骨细胞的分化和功能机制，将有助于更详细地了解正畸牙齿移动的基础和机械应力牙周膜的反应，组织中少

At the time when a mechanical force is applied onto the tooth, mechanical stress is loaded on the periodontal tissues. A number of osteocytes are located in the bone matrix, communicating each other, as well as with the osteoblasts on the bone surface, via cytoplasmatic processes and gap junctions. Such a cellular network is speculated to have certain important functions for the adaptation to a mechanical loaded environment by the detection of mechanical stress.In the present study, in order to investigate the role of osteocytes in bone resorption, we examined the effects of purified chick osteocyte-derived protein (ODP) and Rho-GTP-dissociation inhibitor (Rho-GDI) on bone resorption. Recently, we established a culture system which provided with human mature osteoclasts from peripheral mononuclear blood cells (PMBC) by using M-CSF and human soluble RANKL (sRANKL) in the absence of osteoblasts and stromal cells. FITC-labelled alpha-actinin pre-microinjected into human osteoclasts was in … More corporated into podosomes which lined the periphery of the cells. Although the podosomes were still observed after the injection of buffer, microinjection of ODP and Rho-GDI caused disruption of podosomes within 30 min of injection. Furthermore, both proteins markedly inhibited pit formation, whereas the conditioned medium of osteocytes had no effect.This study has also focused on a novel cysteine proteinase, cathepsin K, which is through to be specifically expressed in osteoclasts and plays an important part in osteoclastic bone resorption. We have investigated the mechanism of alveolar bone remodelling during orthodontic tooth movement based on an examination of changes in cathepsin K mRNA expression in parallel with the histological changes in alveolar bone.Therefore, further insights into osteoclasts differentiation and function mechanisms may provide stronger bases that will help to understand with more detail the fundaments of orthodontic tooth movement and the reaction of mechanically stressed periodontal tissues. Less