CGRP 对牙种植体周骨结合中微循环改建的作用及机制研究

The study of microcirculation is a key point to reveal phenomena of life in modern science. A good state of microcirculation around dental implant is fundamental in initiating osseointegration. The regulatory effect of calcitonin gene-related peptide (CGRP) on peri-implant bone metabolism has attracted wide attention. However, its effect on local micro-vessels has not been reported. In the previous studies, we found CGRP-positive nerve fibers presented regular distribution and changes around titanium implant, further study observed its relationship with local micro-vessels distribution. The above results indicated that CGRP might be correlated with the physiology of microcirculation around implant. Therefore, in the view of microcirculation for the first time, the regulation effect of CGRP on peri-implant angiogenesis during coupling with osteogenesis will be explored in this program. The distribution of micro-vessels in local bone will be detected by angiography by μCT analysis. The biological characterization of titanium plates at the presence of CGRP will be evaluated in vitro by varied molecular biological techniques. Furthermore, the essential genes and signaling pathways regarding CGRP-induced angiogenesis and osteogenesis will be studied by microarray analysis. After that, the mechanism of how CGRP regulates reconstruction of peri-implant microcirculation will be explored with CGRP-gene knockout mice. The method of compositing CGRP to the implant will be also studied. The results of this program will complement and integrate the present theory of implantology, and will be of significance in improving dental implant success.

微循环研究是现代科学揭示生命现象的重要切入点，牙种植体周良好的微循环对启动种植体骨结合至关重要。降钙素基因相关肽(CGRP)对种植体周骨代谢的调控作用已引起广泛关注，但对局部微血管的影响未见报道。本课题组前期研究发现，CGRP阳性神经纤维在种植体周呈规律性分布变化，并与局部微血管的分布相关联，提示CGRP可能与种植体周微循环的正常运行存在联系。因此，本课题首次以微循环为切入点探究CGRP调控种植体周成骨与成血管的交互效应，拟采用血管造影联合microCT分析等技术，追踪微循环在局部骨组织中的分布；运用多种分子生物学手段评价CGRP对钛片体外生物学性能的影响；并采用微阵列分析CGRP介导成血管、成骨的关键基因及通路调控网络；运用CGRP基因敲除小鼠模型研究其对种植体周微循环改建的影响及机制；并探索牙种植体复合CGRP的方法。研究结果对进一步完善种植学理论，提高牙种植体成功率具有重要意义。

微循环研究是现代科学揭示生命现象的重要切入点，牙种植体周良好的微循环对启动种植体骨结合至关重要。降钙素基因相关肽(CGRP)对种植体周骨代谢的调控作用已引起广泛关注，但对局部微血管的影响未见报道。因此，本课题首次以微循环为切入点探究CGRP调控种植体周成骨与成血管的交互效应。本课题首先通过血管造影联合microCT分析，观察到种植体周骨组织内血管的形态和变化规律；从而应用该技术、PCR和组织切片等方法，完成CGRP对种植体周微循环和骨结合的体内实验研究，发现CGRP可促进种植体周血管再生和舒张以及骨结合作用；采用静电造粒法成功制备了负载CGRP的藻酸盐微球并观测该材料可促进小鼠颅顶骨缺损的愈合；体外采取内皮细胞和骨髓间充质干细胞以及成骨细胞共培养模型，发现CGRP可以促进骨髓间充质干细胞和内皮细胞相互趋化，稳固血管壁的作用以及CGRP在成骨细胞和血管内皮细胞交互效应中的主要作用方式和重要信号分子；表达谱分析CGRP介导成骨、成血管的关键基因及通路调控网络。研究结果对进一步完善种植学理论，提高牙种植体成功率具有重要意义，为深入了解种植体周微血管在骨结合进程中的作用提供了重要的实验依据，开辟了以微循环为切入点探究神经肽类物质调控种植体局部成血管、成骨的研究新领域，为深入了解种植体-骨结合界面代谢的内在机制供新的研究思路和理论基础，可为肿瘤、糖尿病、肾病、骨质疏松症患者伴发微循环障碍时的种植治疗策略提供理论及实验依据，具有研究创新性和深远的应用前景。