Signal transduction mechanisms that mediate normal and pathologic angiogenesis

介导正常和病理性血管生成的信号转导机制

• 批准号: 10064095
• 负责人: Jinjiang Pang
• 金额: $ 43.68万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-04 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10064095
• 关键词: Adult; Animal Model; Apoptosis; Attenuated; Binding; Biological Assay; Biological Process; Blood Vessels; Cell Proliferation; Cell physiology; Cells; Cessation of life; Chronic; Cleaved cell; Communication; DNA Sequence Alteration; Data; Disease; Ectopic Expression; Endothelial Cells; Extracellular Domain; Fibrosis; Functional disorder; Grant; Heart failure; Human; Human Genetics; Hypoxia; Immune; Impairment; In Vitro; Inflammation; Interleukin-1; Interleukins; Knockout Mice; Knowledge; Ligands; Link; Lipids; Lung; Mediating; Membrane; Modeling; Molecular; Monocrotaline; Mus; Pathogenesis; Pathologic Neovascularization; Patients; Plasma; Progressive Disease; Rattus; Recombinants; Regulation; Role; Signal Transduction; Small Interfering RNA; TNF gene; Testing; Therapeutic; Therapeutic Effect; Vascular Endothelial Cell; Vascular remodeling; base; cytokine; experience; hemodynamics; improved; in vivo; inhibitor/antagonist; mRNA Expression; monocyte; nanoparticle; notch protein; novel; novel therapeutic intervention; pressure; prevent; protein expression; pulmonary arterial hypertension; receptor; systemic inflammatory response; vasoconstriction

Title of the grant Signal transduction mechanisms that mediate normal and pathologic angiogenesis Abstract Pulmonary arterial hypertension (PAH) is a progressive disease, characterized by vasoconstriction, cell proliferation, and fibrosis, leading to elevated pulmonary arterial pressure and often causing right heart failure and death. There is no cure for this disease. Therefore, novel mechanistic studies and new therapeutic strategies are urgently needed. Elevation of plasma cytokines in PAH patients is a hallmark of inflammation. As the major effector, monocytes release cytokines and infiltrate in perivascular regions of the lung. Depletion of monocytes attenuates vascular remodeling and hemodynamic changes in PAH animal models. This evidence implies a communication between monocytes and endothelial cells (ECs). However, the underlying mechanisms are not well understood. The objective of the current proposal is to define the role of extracellular domain of cleaved delta like 4 (exDll4) in the pathogenesis of PAH and its mechanisms. In vitro, we discovered that calpain1 can cleave Dll4. We also found that TNF and IL-1 increases Dll4 expression, Dll4 cleavage in human monocyte, and exDll4 release from monocytes. Furthermore, we found that recombinant exDll4 significantly increased apoptosis and decreased barrier function in ECs. Seeking the mechanism of action, we found exDll4 associated with intact Dll4, and this interaction prevents Dll4 binding to Notch1 and thus inhibits Notch1 activation. In vivo, we found that Dll4 expression and exDll4 release in monocyte are significantly elevated in PAH mice as well as in PAH patients. However, Notch1 signaling is decreased in lungs during PAH progression in mice and rats. Based on these findings, we hypothesize that exDll4 derived from monocytes is crucial for PAH progression by inducing apoptosis and impairing barrier function in lung EC. Mechanistically, exDll4 forms a heterodimer with Dll4 to prevent the association of Dll4 and Notch1, blocking Notch1 signaling. To test our hypothesis, we propose three aims. Aim 1. Define the regulatory mechanisms of Dll4 expression and exDll4 release from monocyte in PAH. Aim 2. Determine the biological function of exDll4-Notch1 in lung EC and its molecular mechanisms. Aim 3. Characterize the therapeutic effects of inhibiting monocyte Dll4 on PAH progression. Accomplishing these aims will 1) fill the knowledge gap regarding the mechanisms of vascular remodeling and EC dysfunction in the pathogenesis of PAH mediated by monocyte derived exDll4; 2) reveal the regulation of Dll4 cleavage; and 3) invent a novel therapeutic strategy for PAH by targeting monocyte Dll4.

补助金名称 介导正常和病理性血管生成的信号转导机制 抽象的 肺动脉高压（PAH）是一种进行性疾病，其特征是血管收缩、细胞 增殖和纤维化，导致肺动脉压升高并常常导致右心衰竭 和死亡。这种疾病无法治愈。因此，新的机制研究和新的治疗策略 是迫切需要的。 PAH 患者血浆细胞因子升高是炎症的标志。作为主要 作为效应器，单核细胞释放细胞因子并浸润肺血管周围区域。单核细胞耗竭 减弱 PAH 动物模型中的血管重塑和血流动力学变化。这个证据意味着 单核细胞和内皮细胞（EC）之间的通讯。然而，根本机制并不 很好理解。当前提案的目标是定义切割的细胞外结构域的作用 Delta Like 4 (exDll4) 在 PAH 发病机制及其机制中的作用。在体外，我们发现 calpain1 可以 切割 Dll4。我们还发现 TNF 和 IL-1 会增加人单核细胞中 Dll4 的表达、Dll4 的裂解， 和 exDll4 从单核细胞中释放。此外，我们发现重组 exDll4 显着增加 EC 细胞凋亡和屏障功能下降。寻找作用机制，我们发现exDll4相关 与完整的 Dll4 结合，这种相互作用阻止 Dll4 与 Notch1 结合，从而抑制 Notch1 激活。体内， 我们发现单核细胞中 Dll4 的表达和 exDll4 的释放在 PAH 小鼠以及 在 PAH 患者中。然而，在小鼠和大鼠的 PAH 进展过程中，Notch1 信号在肺部减弱。 基于这些发现，我们假设源自单核细胞的 exDll4 对于 PAH 进展至关重要 诱导细胞凋亡并损害肺 EC 的屏障功能。从机制上讲，exDll4 与 Dll4阻止Dll4和Notch1的关联，阻断Notch1信号传导。为了检验我们的假设，我们提出 三个目标。目的 1. 明确单核细胞 Dll4 表达和 exDll4 释放的调控机制 多环芳烃。目的2.确定exDll4-Notch1在肺EC中的生物学功能及其分子机制。目的 3. 表征抑制单核细胞 Dll4 对 PAH 进展的治疗效果。实现这些 目标将 1) 填补关于血管重塑和 EC 功能障碍机制的知识空白 单核细胞衍生的 exDll4 介导的 PAH 发病机制； 2）揭示Dll4裂解的调控；和 3) 通过靶向单核细胞 Dll4 发明了一种新的 PAH 治疗策略。