种植体表面带电涂层调控成骨细胞粘附、分化的信号通路研究

项目名称： 种植体表面带电涂层调控成骨细胞粘附、分化的信号通路研究

项目编号： No.31470929

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 生物科学

项目作者： 马楚凡

作者单位： 中国人民解放军第四军医大学

项目金额： 90万元

中文摘要： 我们的研究发现负电TiO2涂层促进了成骨细胞的有效粘附和分化，而正电TiO2涂层起抑制作用，但其分子机制仍不明确。根据前期的研究结果，本课题提出了材料表面电位的识别、导入细胞、调控胞内信号分子变化和调节效应蛋白表达的可能机制：一、表面电位通过钙离子-吸附蛋白-Integrin-Vinculin-ROCK通路影响成骨细胞的有效粘附并诱发细胞骨架的重组；二、细胞骨架的重组通过IQGAP1的表达影响Cadherin/catenin复合物的连接，来改变胞浆内游离β-catenin的浓度并调控β-catenin的核转移，从而激活或抑制β-catenin介导的转录，来调控成骨细胞的分化。本课题拟采用细胞和分子生物学方法进行系统研究，证实该假设，并用体内试验加以验证，从而阐明表面电位影响成骨细胞粘附、分化的具体分子机制，更好的理解细胞与材料间的相互作用，这对骨植入材料表面的优化设计具有重要的指导意义。

中文关键词： 表面电位；成骨细胞；细胞粘附；细胞分化；信号通路

英文摘要： It has showed that surface charge of material may play a key role on the interactions between the bone tissue and implant. The mechanism is still unclear because it's very hard to exactly measure the polarity and amounts of surface charges on titanium implant in body environment. The unique method has been developed by our team to obtain electrically polarized TiO2 coatings on the surface of titanium implant. The polarity and amounts of surface charges in TiO2 coating can be measured by testing the thermally stimulated depolarization current (TSDC). After electrical polarization treatment, it was found that bonelike apatite-forming ability in SBF was significantly enhanced on the negative-charged coating while the positive-charged coating inhibited the apatite nucleation. The shape of the osteoblast and the arrangement of actin cytoskeleton were totally different between the negative-charged surface and the positive-charged surface.The adhesion and differentiation of MG63 osteoblast were significantly promoted on the negative-charged surface. According to our previous results, we proposed two hypotheses:① surface charge regulates osteoblast adhesion by the signal passway of Ca2+-Protein -Integrin-Vinculin-Rho/ROCK;② surface charge regulates the differentiation of osteoblast by the signal passway of IQGAP1/β-catenin,which is associated with cytoskeletal reorganization. The purpose of the research project is to verify the research hypotheses mentioned above and to further investigate the biological effects of surface charge of TiO2 coating on bone formation,which is very helpful for understanding the interactions between the bone tissue and implant materials.The research protocol will be composed of three parts:① the mechanism study of electrical polarization will be done using surface analysis and the TSDC; ② the mechanism study of surface charge on adhesion and differentiation of osteoblast will be investigated by a series of experiments of cytobiology and molecular biology;③ the animal experiments will be done to further test and verify the research hypotheses in vivo.

英文关键词： surface charge;osteoblast;cell adhesion;cell differentiation;signal pathway