Osteoblast stimulation effects on osteoclast activity

描述（由申请人提供）：本研究的长期目标是阐明植入物诱导骨质溶解的机制以及机械负荷对该过程的影响。本申请中提出的生物学培训与申请人的工程背景相结合，将使申请人能够完成本文提出的研究，并开发未来针对骨质溶解的研究。本申请的目的是确定底物在增强成骨细胞的机械反应性中的作用以及刺激的可溶性因子对成骨细胞的影响。具体而言，我们将确定是否基板有助于细胞扁平化，细胞网络和细胞间通讯，通过分析这些因素在通信能力和缺陷成骨细胞系的人工和天然基板。然后，我们将通过定量流体流动诱导的细胞分泌的骨保护素（OPG）及其配体（RANKL）水平来确定这些因素是否有助于成骨细胞的机械反应性。最后，我们将通过定量OPG、RANKL和破骨细胞在存在和不存在成骨细胞液流研究中刺激介质的情况下的骨吸收，确定成骨细胞反应性增强是否与破骨细胞生成和功能性骨吸收活性抑制相关。我们认为，相对于人工基质，天然基质通过促进细胞扁平化、细胞网络化和细胞间通讯来促进成骨细胞的机械反应性。此外，我们提出，耦合机制之间存在的成骨细胞和骨细胞，使编排骨形成和吸收和刺激成骨细胞活性的结果，在促进抑制破骨细胞和骨细胞活性的可溶性因子上调。未来的工作将集中在发展的原位力学转导模型纳入骨基板。这一领域的研究将阐明正常细胞感知和响应机械负荷的机制以及环境在这一过程中的影响。这是理解这些与疾病和改变的负荷环境相关的机制的分解的第一步。这项工作有几个临床相关的应用，包括植入和转移诱导的骨质溶解，骨质疏松症，骨硬化症，骨折愈合和功能性组织工程。

DESCRIPTION (provided by applicant): The long-term goal of this research is to elucidate the mechanisms involved in implant-induced osteolysis and the effect(s) of mechanical loading on this process. Biological training proposed in this application augmented with the applicant's engineering background, would enable the applicant to complete the research proposed herein and develop future research aimed at osteolysis. The goal of the current application is to determine the role of the substrate in enhancing the mechanoresponsiveness of osteoblastic cells and the effects of stimulated soluble factors on osteoclastic cells. Specifically, we will determine if substrate contributes to cell flattening, cell networking and cell-cell communication by analyzing these factors in communication-competent and -deficient osteoblastic cell lines on artificial and native substrates. We will then determine if these factors contribute to the mechanoresponsiveness of osteoblastic cells by quantifying fluid flow-induced cell secreted levels of osteoprotegerin (OPG) and its ligand (RANKL). Finally, we will determine if enhanced osteoblastic responsiveness is coupled to an inhibition of osteoclastogenesis and functional osteoclastic activity by quantifying OPG, RANKL and bone resorption by osteoclasts in the presence and absence of stimulated media from the osteoblastic fluid flow studies. We propose that a native substrate, relative to an artificial substrate, contributes to the mechanoresponsiveness of osteoblastic cells by promoting cell flattening, cell networking and cell-cell communication. Furthermore, we propose that coupling mechanisms exist between osteoblastic and osteoclastic cells which enable the orchestration of bone formation and resorption and that stimulation of osteoblastic activity results in an upregulation of soluble factors promoting inhibition of osteoclastogenesis and osteoclastic activity. Future work will focus on the development of in situ mechanotransduction models incorporating bone substrates. Research in this area will illuminate the mechanisms by which normal cells sense and respond to mechanical loading and the effects of the milieu in this process. This is the first step in understanding the breakdown of these mechanisms associated with disease and altered loading environments. This work has several clinically relevant applications including implant- and metastatic-induced osteolysis, osteoporosis, osteopetrosis, fracture healing and functional tissue engineering.