Morphogenesis of the pulmonary artery smooth muscle layer

肺动脉平滑肌层的形态发生

• 批准号: 8212890
• 负责人: Daniel Greif
• 金额: $ 10.15万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8212890
• 关键词: Morphogenesis; pulmonary; artery; smooth; muscle

DESCRIPTION (provided by applicant): Dedifferentiation and enhanced proliferation and motility of vascular smooth muscle cells (VSMCs) are key elements in the pathogenesis of many vascular diseases. Thus, a detailed understanding of the development of the VSMC layer of normal blood vessels promises to provide critical insights into vascular disease. However, the processes underlying the morphogenesis of any specific vessel or vascular bed are not well understood. The central goal of this proposal is to elucidate the key molecular and cellular events encompassing the morphogenesis of the smooth muscle cell (SMC) layer of the left pulmonary artery during the initial four days of murine lung development. This goal is the first step towards the long term objective of delineating the critical events in the building of all layers of the pulmonary artery throughout development. An essential element of achieving these goals is to characterize the roles specific signaling pathways play in pulmonary artery development. Platelet derived growth factor (PDGF)-induced signaling has been implicated in the pathogenesis of pulmonary artery hypertension and restenosis following coronary artery angioplasty; yet, the specific effects of PDGF signaling in these diseases or in the morphogenesis of large vessels remain elusive. I hypothesize that signaling through the PDGF pathway is critical for the maintenance, proliferation and/or recruitment of a multipoint early lung mesenchymal cell population that has the capacity to differentiate into the SMC layer of the left pulmonary artery. The proposal has three specific aims: 1) establish a timeline of molecular markers and cellular events that identify specific stages during the transition of a murine lung mesenchymal cell into a differentiated left pulmonary artery SMC and relate this timeline to'endothelial cell and non-vascular tissue development; 2) identify the pattern and effects of activation of PDGF receptor-mediated signaling pathways in left pulmonary artery SMC development; 3) determine the fate in the lung of early PDGF receptor-beta-positive mesenchymal cells through lineage analysis. To achieve these aims, lungs will be dissected from wildtype and transgenic mouse embryos and subjected to whole mount immunostaining, in situ hybridization or X-gal staining. In selected experiments, embryonic lungs will be cultured prior to analysis. Confocal microscopy will be used to analyze fluorescent stains on a cellular level. In sum, the proposed work will make the left pulmonary artery the best understood example of morphogenesis of a specific blood vessel. These studies will yield critical insights into the mechanisms underlying prevalent vascular diseases such as coronary artery atherosclerosis. In addition, this work promises to advance the investigation of critically understudied disorders of smooth muscle cell physiology in the lung, such as pulmonary artery hypertension and lymphangioleiomyomatosis.

描述（由申请人提供）：血管平滑肌细胞（VSMC）的去分化和增强和运动性增强和运动性是许多血管疾病发病机理的关键因素。因此，对正常血管VSMC层的发展的详细理解有望为血管疾病提供关键的见解。但是，尚不清楚任何特定血管或血管床形态发生的基础过程。该提案的核心目标是阐明涵盖鼠肺发育的最初四天的左肺动脉平滑肌细胞（SMC）层的形态发生的关键分子和细胞事件。这个目标是朝着长期目标迈出的第一步，即描述整个发育过程中肺动脉所有层的关键事件。 实现这些目标的一个重要因素是表征特定的信号通路在肺动脉发育中起的作用。血小板衍生的生长因子（PDGF）诱导的信号传导与冠状动脉血管成形术后肺动脉高压和再狭窄的发病机理有关。然而，PDGF信号传导在这些疾病或大血管形态发生中的特定作用仍然难以捉摸。我假设通过PDGF途径的信号对于维持，增殖和/或募集多点早期肺间充质细胞群的维持，增殖和/或募集至关重要，该肺间充质细胞群具有分化为左肺动脉的SMC层的能力。 该提案具有三个具体的目的：1）建立一个分子标记和细胞事件的时间表，这些时间表在鼠肺肺间充质细胞过渡到分化的左肺动脉SMC期间鉴定特定阶段，并将这一时间线与内皮细胞和非血管组织发育相关联； 2）确定左肺动脉SMC发育中PDGF受体介导的信号通路激活的模式和影响； 3）通过谱系分析确定早期PDGF受体β阳性间充质细胞的肺中的命运。为了实现这些目标，将从野生型和转基因小鼠胚胎中剖析肺，并进行整个固定免疫染色，原位杂交或X-GAL染色。在选定的实验中，胚胎肺将在分析前进行培养。共聚焦显微镜将用于分析细胞水平上的荧光污渍。 总而言之，拟议的工作将使左肺动脉成为特定血管形态发生的最好的例子。这些研究将产生对流行的血管疾病（例如冠状动脉粥样硬化）基本机制的关键见解。此外，这项工作有望进一步研究肺部平滑肌细胞生理的严格研究的疾病，例如肺动脉高血压和淋巴血管血管瘤病。