OSTEOBLASTOGENESIS IN MODELED MICROGRAVITY

微重力模型中的成骨细胞发生

• 批准号: 7215170
• 负责人: Jay M. McDonald
• 金额: $ 25.02万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-15 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7215170
• 关键词: Address; Adipocytes; Age; Aging; Alkaline Phosphatase; Astronauts; Beds; Biological; Bone Marrow; Cell Culture System; Cell Differentiation process; Cell physiology; Condition; Core-Binding Factor; DNA Binding; Data; Development; Elderly; Environment; Fatty acid glycerol esters; Force of Gravity; Gelshift Analysis; Gene Expression; Gene Proteins; Genes; Hormones; Human; Integrins; Literature; Maintenance; Mechanical Stress; Mediating; Mesenchymal; Mesenchymal Stem Cells; Metaphysis; Microgravity; Modeling; Molecular; Ocular orbit; Osteoblasts; Osteogenesis; Osteoporosis; PPAR gamma; Patients; Peroxisome Proliferator-Activated Receptors; Personal Satisfaction; Play; RNA; Rattus; Regulation; Research Personnel; Role; Signal Pathway; Signal Transduction; Skeletal system; Space Flight; State of Zero Gravity; System; Techniques; Testing; Transactivation; Travel; Trichrome stain; Western Blotting; adipocyte differentiation; base; bone; bone disuse atrophy; bone loss; bone strength; day; drug development; inhibitor/antagonist; insight; lipid biosynthesis; mineralization; oil red O; older patient; programs; response; stem; transcription factor

DESCRIPTION (provided by applicant): Bone loss is a major consequence of spaceflight as well as aging and disuse. These conditions are marked by a decrease in the osteoblastogenesis of mesenchymal stem cells and an increase in adipogenesis. Cbfa1 is an essential transcription factor in osteoblast differentiation and bone formation. In addition, PPAR-gamma was shown to be crucial for adipocyte differentiation. Given this strong relationship between osteogenesis and adipogenesis, we hypothesize that modeled microgravity disrupts integrin-mediated signaling leading to alterations in the expression and/or activation of both Cbfa1 and PPAR( in human mesenchymal stem cells (hMSC), which results in suppressed osteoblast differentiation and increase adipogenesis. To test this hypothesis, hMSC will be grown in a Rotary Cell Culture System with a high aspect ratio vessel. The aims of this study are: (1) Characterize the effects of modeled microgravity on human mesenchymal stem cell differentiation. Modulation of osteoblastogenesis and adipogenesis will be examined by alkaline phosphatase, von Kossa, oil red O and trichrome staining. RNA analyses will be performed to demonstrate the modulation of osteoblastic and adipogenic gene expression. (2) Characterize the molecular mechanisms responsible for the effects of modeled microgravity on human mesenchymal stem cells. Western blot and gel shift analysis and transactivation studies will be utilized to elucidate the mechanism. (3) Identifying agents capable of reversing the modeled microgravity inhibition of osteoblastogenesis. Using the same techniques employed in Aims 1 and 2, we will identify agent/s capable of blocking microgravity-induced bone loss. Findings from these studies will provide insight into mechanisms involved in the effect of weightlessness on mesenchymal cell function, thus addressing the requirements of this PA (PA-00-088). A viable basis will thereby be provided for the development of drugs that can alter Cbfa1 and/or PPARgamma and mediate increased bone formation in astronauts, elderly and patients with disuse osteoporosis.

描述（由申请人提供）：骨质流失是太空飞行以及老化和废弃的主要结果。这些疾病的特征是间充质干细胞的成骨细胞生成减少和脂肪形成的增加。 CBFA1是成骨细胞分化和骨形成的基本转录因子。另外，PPAR-GAMMA被证明对于脂肪细胞分化至关重要。鉴于成骨和成生成之间的这种密切关系，我们假设建模的微重力破坏了整联蛋白介导的信号传导，从而导致CBFA1和PPAR的表达和/或激活改变（在人间充质干细胞（HMSC）中），从而导致抑制的成核细胞分化导致成骨细胞分化。并增加脂肪形成。 为了检验该假设，HMSC将在具有高纵横比血管的旋转细胞培养系统中生长。这项研究的目的是：（1）表征建模微重力对​​人间充质干细胞分化的影响。碱性磷酸酶，冯·科萨（Von Kossa），油红色O和三色染色的调节将检查成骨细胞生成和掺杂的调节。将进行RNA分析以证明成骨细胞和成脂基因表达的调节。 （2）表征负责建模微重力对​​人间充质干细胞的影响的分子机制。蛋白质印迹和凝胶转移分析和反式激活研究将用于阐明该机制。 （3）鉴定能够逆转模型的微生物发生的抑制剂的药物。使用AIMS 1和2中使用的相同技术，我们将确定能够阻止微重力诱导的骨质流失的药物。这些研究的发现将提供有关失重对间充质细胞功能影响的机制的洞察力，从而解决了该PA的要求（PA-00-088）。因此，将提供可行的基础，用于开发可以改变CBFA1和/或ppargamma的药物，并介导宇航员，老年人和废除骨质疏松症患者的骨形成增加。