Reaction of intercellular network of osteocytes in alveolar bone during experimental tooth movement

实验性牙齿移动过程中牙槽骨骨细胞间网络的反应

• 批准号: 10470449
• 负责人: MIZOGUCHI Itaru
• 金额: $ 7.94万
• 依托单位: Health Sciences University of Hokkaido
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10470449/
• 关键词: tooth movement; osteocyte; cell death; Apoptosis; necrosis; メカニカル・ストレス; メカニカルストレス

Osteocytes are buried within the bone matrix and form complicated cellular networks between neighboring osteocytes and/or osteoblasts on bone surfaces. It is proposed that osteocytes have very important role of bone remodeling. However little is known on the effect of mechanical stress on osteocytes and their intercellular network in the alveolar bone during orthodontic tooth movement. The purpose of this study was to examine the intercellular network in alveolar bone on pressure and tension sides during experimental tooth movement, using morphometrical analysis, immunohistochemistry and in situ hybridization technique.1. Animals and experimental tooth movement.In 8-week-old male Wistar rats, the upper first molar was forced to move mesially with an average load of 10g by a nickel-titanium superelastic wire (0.01 inch in diam.). We previously reported that the method was suitable for the observation of osteocytes adjacent to the hyalinized periodontal tissue.2. Morphological change of osteocytes during experimental tooth movement.We developed a method to observe osteocytes by immunofluoresence with Alexa 488 labelled phalloidin and DAPI under confocal laser scanning microscopy (CLSM). CLSM showed that chromatin condensation, nuclear fragmentation and cytoplasmic destruction appeared in several osteocytes adjacent to the hyalinized periodontal tissues. Also, we carried out TUNEL method and electronmicroscopic observation to identify the cell death of osteocytes. The results indicate that cell death of osteocytes during experimental tooth movement may be due to disruption of intercellular network between osteoblasts and osteocyte, but not to direct reaction of osteocytes by mechanical stress. To know the dynamics of intercellular network in alveolar bone, further investigations concerning involvement of several growth factors and cytokines related to bone metabolism is necessary.

骨细胞埋藏在骨基质内，并在骨表面上的相邻骨细胞和/或成骨细胞之间形成复杂的细胞网络。提出骨细胞在骨重塑中具有非常重要的作用。然而，对于正畸牙齿移动期间机械应力对牙槽骨中的骨细胞及其细胞间网络的影响知之甚少。本研究的目的是利用形态测量分析、免疫组织化学和原位杂交技术，研究实验性牙齿移动过程中牙槽骨压力侧和张力侧的细胞间网络。1．动物和实验性牙齿移动。在8周龄的雄性Wistar大鼠中，通过镍钛超弹丝（直径0.01英寸）以平均10g的负载迫使上第一磨牙向近中移动。我们之前报道该方法适用于观察透明变性牙周组织附近的骨细胞。 2．实验性牙齿移动过程中骨细胞的形态变化。我们开发了一种在共焦激光扫描显微镜（CLSM）下用Alexa 488标记的鬼笔环肽和DAPI通过免疫荧光观察骨细胞的方法。 CLSM显示在透明变牙周组织附近的多个骨细胞中出现染色质浓缩、核碎裂和细胞质破坏。此外，我们还进行了TUNEL法和电子显微镜观察来鉴定骨细胞的细胞死亡。结果表明，实验性牙齿移动过程中骨细胞的细胞死亡可能是由于成骨细胞和骨细胞之间的细胞间网络破坏所致，而不是由于机械应力对骨细胞的直接反应。为了了解牙槽骨细胞间网络的动态，有必要进一步研究与骨代谢相关的几种生长因子和细胞因子的参与。

项目成果

SaSano Y.: "Protein Expression of major bone.ECM befor and after calufication"Anat Embryol. (in press).

SaSano Y.：“主要骨的蛋白质表达。钙化前后的 ECM”Anat Embryol。

Sasano Y: "The implanted octacalcium phosphate (OCP) stimulates osteogenesis of closely committed osteoblastic cell in the rat calvarial periosteum" The anatomical Records. (in press).

Sasano Y：“植入的磷酸八钙（OCP）刺激大鼠颅骨骨膜中紧密结合的成骨细胞的成骨”解剖记录。

Sasano.Y: "Expression of major bone extracellular matrix proteins during embryonic osteogenesis in rat mandibles."Anat Embryol. 202・1. 31-37 (2000)

Sasano.Y：“大鼠下颌骨胚胎成骨过程中主要骨细胞外基质蛋白的表达”，Anat Embryol 202・1（2000）。

溝口 到: "下顎骨の成長現象と下顎頭軟骨の生物学的特徴"東北大学歯学雑誌. 18・1. 1-21 (1999)

Itaru Mizoguchi：“下颌生长现象和下颌骨髁软骨的生物学特性”东北大学牙科杂志18・1（1999）。

Abiko Y, Nishimura M, Mitamura J, Mizoguchi I Rahemtulla F, Kaku T: "Immunohistochemical localization of large chondroitin sulphate proteoglycan in porcine gingival epithelia"Eur J Morphol. (in press). (2001)

Abiko Y、Nishimura M、Mitamura J、Mizoguchi I Rahemtulla F、Kaku T：“猪牙龈上皮中大硫酸软骨素蛋白多糖的免疫组织化学定位”Eur J Morphol。