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Endothelial Cell Cycle State and Cell Fate

内皮细胞周期状态和细胞命运

基本信息

批准号：
10208947
负责人：
Karen Kemper Hirschi
金额：
$ 52.61万
依托单位：
UNIVERSITY OF VIRGINIA
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-15 至 2023-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10208947
关键词：
Arteries Blood Circulation Blood Vessels Blood capillaries Blood flow Cardiovascular system Cell Culture System Cell Cycle Cell Cycle Regulation Cell Proliferation Cells Clinical Data Defect Development Ectoderm Embryonic Development Endoderm Endothelial Cells Endothelium Engineering Ensure Evaluation Exhibits G1 Arrest G1 Phase Gene Expression Genes Growth Human In Vitro Maintenance Mesoderm Metabolic Modeling Molecular Mus Natural regeneration Nutrient Oxygen Pathology Phenotype Process Regenerative Medicine Regulation Research Role Signal Pathway Signal Transduction Structure Testing Tissue Engineering Tissues Tube Up-Regulation Vascular remodeling Vascularization Veins Venous Venous Malformation Waste Products arteriole blood vessel development cell growth embryonic stem cell human stem cells in vivo in vivo Model injured injury and repair insight ischemic injury mechanotransduction migration mouse model neovascularization notch protein novel postnatal prevent repaired replacement tissue response restoration shear stress vascular injury vasculogenesis venule

项目摘要

Establishing a functional vascular network is a rate-limiting step in embryonic development, the repair of injured tissues, and the engineering of tissue replacements. Although we have made progress in identifying factors that promote endothelial cell proliferation and sprouting, we lack understanding of how to properly control endothelial cell growth and phenotypic specialization during vascular remodeling, which has created a significant roadblock for clinical therapies, tissue engineering and regenerative medicine. Although multiple signaling pathways have been implicated in the regulation of arterial-venous network formation, including flow-induced mechanotransduction and Notch signaling, the mechanisms by which these signals coordinately regulate endothelial cell growth suppression and identity were unclear. Our recent studies revealed that remodeling vascular plexi are subject to systemic blood circulation, and that shear stress of different magnitudes promotes differential growth responses and gene expression. That is, arterial/arteriolar shear stress levels promote Notch signaling, and downstream p27-induced late G1 phase arrest that enables arterial gene expression (Fang 2017). Conversely, flow magnitudes typical of veins/venules induce early G1 arrest, and enables upregulation of venous genes. Interestingly, distinct endothelial cell cycle states appear to be maintained in arteries vs. veins postnatally. We know very little about the role of cell cycle control in endothelial cell fate decisions, or the differential signaling pathways induced by vessel-specific flow magnitudes, and how they may coordinately induce and maintain endothelial cell cycle state and identity. The scientific premise of our research is that endothelial cell cycle control is required for proper arterial and venous specification, such that when endothelial cells are in different cell cycle states, they exhibit different propensity for arterial vs. venous gene expression. Support for this idea comes from studies in embryonic stem cells that show cells in early vs. late G1 phase have a propensity for mesoderm/endoderm vs. ectoderm fate, respectively (Paulkin 2014). Thus, our hypothesis is that differential flow forces in arteries and veins induce different intracellular signaling pathways that promote distinct endothelial cell cycle states, creating distinct windows of opportunity for the regulation of arterial vs. venous gene expression. To ensure scientific rigor, we will test this hypothesis in vivo in models of arterial- venous network formation and repair, and in vitro in human endothelial cell culture systems that allow flow manipulation. We will define mechanisms by which vessel-specific flow magnitudes modulate endothelial cell cycle state, determine how distinct endothelial cell cycle states enable differential phenotypic specialization (artery vs. vein), and determine whether manipulation of endothelial cell cycle state can prevent or correct arterial-venous malformations and enhance post-injury vascular repair. Evaluation of this hypothesis will yield novel fundamental insights into blood vessel formation and regeneration that can be used to create human microvasculature ex vivo and treat vascular pathologies.

建立功能性血管网络是胚胎发育的限速步骤，修复受伤的组织和组织替代工程。尽管我们在识别方面取得了进展促进内皮细胞增殖和出芽的因素，我们缺乏了解如何正确控制血管重塑过程中内皮细胞的生长和表型特化，这创造了显着的临床治疗、组织工程和再生医学的障碍。虽然多重信令通路与动静脉网络形成的调节有关，包括血流诱导的机械转导和 Notch 信号传导，这些信号协调调节的机制内皮细胞生长抑制和身份尚不清楚。我们最近的研究表明，改造血管丛承受全身血液循环，不同大小的剪切应力会促进差异生长反应和基因表达。也就是说，动脉/小动脉剪切应力水平促进Notch 信号传导，以及下游 p27 诱导的 G1 期晚期停滞，从而实现动脉基因表达 (Fang 2017)。相反，静脉/小静脉典型的流量大小会诱导早期 G1 停滞，并能够上调静脉基因。有趣的是，动脉与静脉在出生后似乎维持着不同的内皮细胞周期状态。我们对细胞周期控制在内皮细胞命运决定中的作用或差异信号传导知之甚少由血管特定流量大小诱导的路径，以及它们如何协调诱导和维持内皮细胞周期状态和身份。我们研究的科学前提是内皮细胞周期适当的动脉和静脉规格需要控制，这样当内皮细胞处于不同的状态时在细胞周期状态下，它们表现出不同的动脉与静脉基因表达倾向。支持这个想法来自胚胎干细胞的研究，该研究表明早期 G1 期与晚期 G1 期的细胞有以下倾向：分别是中胚层/内胚层与外胚层的命运（Paulkin 2014）。因此，我们的假设是微分动脉和静脉中的流动力诱导不同的细胞内信号传导途径，从而促进不同的内皮细胞周期状态，为动脉与血管的调节创造独特的机会之窗。静脉基因表达。为了确保科学严谨性，我们将在动脉模型中在体内测试这一假设静脉网络的形成和修复，以及在体外允许流动的人内皮细胞培养系统中操纵。我们将定义血管特异性流量大小调节内皮细胞的机制周期状态，确定不同的内皮细胞周期状态如何实现不同的表型特化（动脉与静脉），并确定内皮细胞周期状态的操纵是否可以预防或纠正动静脉畸形并增强损伤后血管修复。对该假设的评估将得出关于血管形成和再生的新颖的基本见解可用于创造人类离体微脉管系统并治疗血管病变。