eN0S/TSP2

eN0S/TSP2

• 批准号: 8607983
• 负责人: Michael Simons
• 金额: $ 46.55万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8607983
• 关键词: Age; Angiogenesis Inhibitors; Biomechanics; Blood flow; Breeding; Cell physiology; Complement; Data; Disease; Endothelial Cells; Exhibits; Feedback; Fibroblast Growth Factor 2; Focal Adhesions; Gene Expression; Healed; Homologous Gene; Impairment; In Vitro; Instruction; Ischemia; Knock-in Mouse; Knock-out; Knockout Mice; Laboratories; Lead; Limb structure; Link; Liquid substance; MAP Kinase Gene; MMP2 gene; Maps; Mediating; Molecular; Mus; Pathway interactions; Patients; Peripheral arterial disease; Phenotype; Process; Production; Property; Proteins; Recovery; Regulation; Reporting; Role; Signal Transduction; Stimulation of Cell Proliferation; THBS2 gene; Testing; Thrombospondin 1; Time; Tissues; Tube; Vascular Endothelial Growth Factor Receptor-2; Vascular Endothelial Growth Factors; Vascular remodeling; Wound Healing; angiogenesis; defined contribution; extracellular; healing; human NOS3 protein; in vivo; migration; mutant; novel therapeutics; research study; response; shear stress; stress activated protein kinase; thrombospondin 2; tissue repair

PROJECT SUMMARY (See instructions): The relationship between thrombospondin 2 (TSP2) and endothelial nitric oxide synthase (eNOS) are not known. Activation of VEGFR-2 via VEGF or by fluid shear stress activates the protein kinase Akt and the endothelial specific Akt substrate, endothelial nitric oxide synthase (eNOS), leading to arteriogenesis and angiogenesis. As inferred from exciting preliminary studies from our laboratories, TSP2 serves as a negative regulator of the Akt-1/eNOS pathway. Previously, we have reported that TSP2 knockout mice (TSP2-K0) demonstrate enhanced arteriogenesis and blood flow recovery in response to limb ischemia and augmented tissue healing. Interestingly, our preliminary studies show that TSP2 levels are elevated in eNOS-KO and Akt1-KO mice, which both display marked impairments in arteriogenesis and angiogenesis and NO, per se, negatively regulates TSP2 levels. Moreover, TSP2/eN0S double knockout (DKO) mice exhibit substantial improvements in blood flow recovery and tissue repair. Thus, we hypothesize that regulation of TSP2 expression by eNOS-derived NO constitutes a previously undefined pro-arteriogenic and pro-angiogenic property of NO. To test this idea, we will: 1. test the hypothesis that the Akt1/eNOS axis mediates arteriogenic and angiogenic responses in vivo, in part, by repressing TSP2 levels; 2. determine the mechanism(s) through which the Akt1/eNOS axis and crosstalk with ERK regulates TSP2 and arteriogenesis; and 3. dissect the regulation of the N0/TSP2 pathway and other endothelial cell functions during in vitro angiogenesis. Collectively, these experiments will allow us to delve deeply into the functional antagonism of arteriogenesis and angiogenesis by TSP2, and to delineate how NO regulates TSP2 gene expression and blood flow recovery after limb ischemia.

项目摘要（参见说明）： 血小板反应蛋白 2 (TSP2) 和内皮一氧化氮合酶 (eNOS) 之间的关系尚不清楚。通过 VEGF 或流体剪切应力激活 VEGFR-2 会激活蛋白激酶 Akt 和内皮特异性 Akt 底物、内皮一氧化氮合酶 (eNOS)，从而导致动脉生成和血管生成。根据我们实验室激动人心的初步研究推断，TSP2 是 Akt-1/eNOS 通路的负调节因子。此前，我们曾报道过 TSP2 敲除小鼠 (TSP2-K0) 在肢体缺血和组织愈合方面表现出增强的动脉生成和血流恢复能力。有趣的是，我们的初步研究表明，eNOS-KO 和 Akt1-KO 小鼠中的 TSP2 水平升高，这两种小鼠的动脉生成和血管生成均表现出明显的损伤，而 NO 本身对 TSP2 水平具有负调节作用。此外，TSP2/eN0S 双敲除 (DKO) 小鼠在血流恢复和组织修复方面表现出显着改善。因此，我们假设 eNOS 衍生的 NO 对 TSP2 表达的调节构成了 NO 先前未定义的促动脉生成和促血管生成特性。为了验证这一想法，我们将： 1. 验证 Akt1/eNOS 轴部分通过抑制 TSP2 水平介导体内动脉生成和血管生成反应的假设； 2. 确定 Akt1/eNOS 轴以及与 ERK 的串扰调节 TSP2 和动脉生成的机制； 3. 剖析体外血管生成过程中 N0/TSP2 通路和其他内皮细胞功能的调节。总的来说，这些实验将使我们能够深入研究 TSP2 对动脉生成和血管生成的功能拮抗作用，并阐明 NO 如何调节肢体缺血后 TSP2 基因表达和血流恢复。