OSTEOCLAST MEDIATED BONE REMODELING

破骨细胞介导的骨重塑

• 批准号: 6100405
• 负责人: Philip A Osdoby
• 金额: $ 24.58万
• 依托单位: BARNES-JEWISH HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-01 至 2000-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6100405
• 关键词: RNase protection assay; biological signal transduction; cell cell interaction; cell differentiation; chemokine; chickens; cytokine; cytokine receptors; enzyme linked immunosorbent assay; hormone regulation /control mechanism; human tissue; immunocytochemistry; in situ hybridization; integrins; laboratory mouse; osteoblasts; osteoclasts; osteogenesis; physiologic bone resorption; polymerase chain reaction; tissue /cell culture

Bone development and remodeling are dependent on a complex interactive network of humoral and local factors produced by bone cells, bone marrow cells, immunocompetent cells, vascular cells, and precursors for these cell populations. Insights obtained as to which osteoblast factors influence osteoclast (Oc) development and how they have helped define the cellular and molecular processes involved in bone development and remodeling and provide potential new therapeutic strategies to overcome endocrine or local disorders in bone formation and resorption becomes uncoupled. The converse of this avenue of research has to date received only limited attention, namely, how Ocs might regulate osteoblast development, activity, and senescence. There is now a growing awareness based on experimental evidence demonstrating that Ocs synthesize and release cytokines, growth factors, matrix molecules, arachidonic acid metabolites, and other reactive species such as superoxide and nitric oxide. These may influence osteoblast differentiation and action. The objectives outlined in this project re designed to build on our observations that Ocs and Oc-like cells can modulate osteoblast development and activity. During the last period of support we showed that Ocs produce small pro-inflammatory peptides know as chemokines, such as IL-8 and GROalpha, in a regulated fashion and that these chemokines influenced osteoblast development and function. To further define the role of Oc-derived chemokines in normal and pathological bone remodeling we propose: 1) to expand our analysis of chemokines proposed by Ocs and their modulation by hormonal cytokine and matrix-dependent signals, 2) to examine the effects of Oc-derived chemokines, such as IL-8 and GROalpha, on osteoblast development and function, including their influence on osteoblast migration, integrin expression, matrix synthesis or degradation, and 3) to identify and characterize osteoblast chemokine receptors has a function of osteoblast development, physiology, and pathophysiology. Recent signal transduction mechanisms involved in Oc- derived chemokine mediated modulation of osteoblastogenesis and activity will be examined. All of the above studies will use a combination of in vivo and in vitro approaches, and model systems including the rat calvarial injection model for histomorphometric studies, human tissue sections for in situ hybridization and immunohistochemical analysis, isolated human and avian Ocs human Oc-like cells, the mouse Oc-like cell developmental, and cells obtained from an IL-8 receptor knockout mouse. Oc chemokine production, mRNA steady state levels and regulation will be assessed by RT=PCR, RNAse protection assay, chemokine ELISA, and in situ hybridization techniques. Osteoblast development and activity will be evaluated based on multiple biochemical and molecular markers of the osteoblast phenotype, including integrins, matrix proteins, and metalloproteinases. Such studies are anticipated to reveal new aspects of normal bone remodeling mechanisms and have potential to lend insight into skeletal pathologies such as osteoporosis, osteoarthritis and other inflammatory bone disorders.

骨骼发育和重塑依赖于一种复杂的相互作用， 由骨细胞、骨髓和骨髓产生的体液和局部因子网络 细胞、免疫活性细胞、血管细胞和这些细胞的前体， 细胞群了解哪些成骨细胞因子 影响破骨细胞（Oc）的发展，以及它们如何帮助定义 参与骨发育的细胞和分子过程， 重塑，并提供潜在的新的治疗策略，以克服 内分泌或局部疾病的骨形成和再吸收成为 分离这一研究途径的匡威迄今已收到 只有有限的关注，即OCs如何调节成骨细胞 发育、活动和衰老。现在人们越来越意识到 基于实验证据表明，OCs合成和 释放细胞因子、生长因子、基质分子、花生四烯酸 代谢物和其他活性物质，如超氧化物和硝酸盐 环氧这些可能会影响成骨细胞的分化和行动。的 本项目中概述的目标旨在建立在我们的 观察到OCs和OCs样细胞可以调节成骨细胞 发展和活动。在上一个支持期间，我们表明， Ocs产生小的促炎肽，称为趋化因子，如 IL-8和GRO α，这些趋化因子 影响成骨细胞的发育和功能。为了进一步明确角色， OC衍生的趋化因子在正常和病理性骨重建中的作用， 建议：1）扩展我们对OCs提出的趋化因子及其 通过激素细胞因子和基质依赖性信号调节，2） 检查OC衍生的趋化因子，如IL-8和GRO α， 对成骨细胞发育和功能的影响， 成骨细胞迁移、整合素表达、基质合成或 降解，和3）鉴定和表征成骨细胞趋化因子 受体具有成骨细胞发育、生理和 病理生理学最近参与Oc-的信号传导机制 衍生趋化因子介导的成骨细胞生成和活性的调节 将被审查。所有上述研究将结合使用在 体内和体外方法，以及包括大鼠在内的模型系统 用于组织形态计量学研究的颅骨注射模型，人体组织 用于原位杂交和免疫组织化学分析的切片， 分离的人和禽类OCs人OCs样细胞、小鼠OCs样细胞 发育和从IL-8受体敲除小鼠获得的细胞。OC 趋化因子的产生，mRNA的稳态水平和调节将是 通过RT=PCR、RNA酶保护试验、趋化因子ELISA和原位 杂交技术成骨细胞的发育和活动将是 基于多个生化和分子标志物进行评估， 成骨细胞表型，包括整合素，基质蛋白， 金属蛋白酶这些研究预计将揭示新的方面， 正常的骨重建机制，并有可能深入了解 骨骼病理学如骨质疏松症、骨关节炎和其他 炎症性骨病