Opposing roles of Nox 1 and Nox 4 in vascular physiology and pathophysiology

Nox 1 和 Nox 4 在血管生理学和病理生理学中的相反作用

• 批准号: 7788447
• 负责人: Kathy K Griendling
• 金额: $ 34.88万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-13 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7788447
• 关键词: Agonist; Antioxidants; Ants; Apoptosis; Arteries; Atherosclerosis; Binding; Blood Vessels; Cardiovascular Diseases; Catalytic Domain; Cell Culture Techniques; Cell Cycle; Cell Differentiation process; Cell Proliferation; Cell physiology; Cells; Data; Development; Disease; Enzymes; Family; Functional disorder; Goals; Growth; Growth Factor; Homologous Gene; Hydrogen Peroxide; Hypertension; In Vitro; Inflammation; Injury; Ischemia; Knock-out; Laboratories; Lesion; Link; Location; Mediating; Membrane; Modeling; NADPH Oxidase; NADPH Oxidase 1; Oxidation-Reduction; Oxygen; Pathogenesis; Pathology; Pharmaceutical Preparations; Phenotype; Physiological; Physiology; Platelet-Derived Growth Factor; Play; Process; Production; Proteins; Reactive Oxygen Species; Regulation; Role; Signal Transduction; Signaling Molecule; Smooth Muscle Myocytes; Source; Stimulus; Superoxides; Testing; Therapeutic; Up-Regulation; Vascular Diseases; Vascular Smooth Muscle; antioxidant therapy; atherogenesis; attenuation; base; bone morphogenic protein; cell growth; cell type; human CYBA protein; in vivo; in vivo Model; inhibitor/antagonist; insight; prevent; response; restenosis; senescence; vascular smooth muscle cell proliferation; vasoconstriction

Reactive oxygen species (ROS) have been implicated in both normal vascular function and in the pathogenesis of vascular disease. For a number of years, our laboratory has been studying the NADPH oxidase (Nox) family of enzymes, which are important sources of ROS in the vasculature. We have shown that cells in the vessel wall express multiple Nox proteins, and that these proteins are differentially regulated, produce different ratios of superoxide and hydrogen peroxide, have distinct intracellular locations, and importantly, appear to serve distinct cellular functions. Nox1 is activated by growth factors and is implicated in vascular smooth muscle proliferation, while Nox4 appears to regulate constitutive ROS production and to maintain cell differentiation. We suggest that while Noxl is activated in pathophysiological situations, Nox4 controls the "redox set point" of the cell, and is regulated by agonists that maintain the differentiated phenotype. We have intriguing new preliminary data suggesting that bone morphogenic protein-4 (BMP4) prevents platelet-derived growth factor (PDGF)-induced proliferation, potentially by activating Nox4. The overall goal of this project is thus to better define the mechanisms that differentially regulate Nox1 and Nox4 and to determine their contrasting roles in the control of cell proliferation. In Aim 1, we will define the mechanisms by which Noxl and Nox4 expression are regulated by PDGF. We hypothesize that the transcriptional mechanisms activated by PDGF include MEF2 to induce Noxl and ERK1/2-mediated activation of FoxMI to repress Nox4. Aim 2 is focused on determining the functional role of Nox4 and inhibition of Noxl in BMP-mediated attenuation of vascular smooth muscle cell proliferation. Our preliminary data show that BMP4 inhibits PDGF-induced proliferation, in part by inhibiting Noxl. BMP4 also increases H2O2 production, leading us to propose that it activates Nox4, resulting in H202-induced upregulation of the cell cycle inhibitor p21^"'. In Aim 3, we plan to determine the role of Noxl and Nox4 in collateral formation. Our model predicts that the expression and activity of Nox4 influence growth factor responsiveness, while PDGF-induced proliferation requires Noxl. In this Aim, we will test this hypothesis using a physiologically relevant stimulus; that of ischemia-induced collateral formation. Finally, in Aim 4, we will determine the role of Nox4 in neointimal formation in vivo. We hypothesize that knockout of Nox4 will reduce physiologically necessary H2O2 production and allow Noxl signaling to proceed unchecked, leading to exacerbated lesion formation after vessel injury. This combination of in vitro and in vivo studies will allow Us to gain insight into the distinct and potentially opposing roles of Noxl and Nox4 in normal vascular function and in vascular disease. These studies will provide import;ant basic information on which to base the development of new therapies that target only those aspects of oxidative signaling that contribute to pathology.

活性氧（ROS）与正常血管功能和血管内皮细胞的增殖有关。 血管疾病的发病机制。多年来，我们的实验室一直在研究NADPH氧化酶（Nox）家族的酶，这是血管系统中ROS的重要来源。我们已经表明，在血管壁中的细胞表达多种Nox蛋白，这些蛋白质的差异调节，产生不同比例的超氧化物和过氧化氢，有不同的细胞内位置，重要的是，似乎服务于不同的细胞功能。Nox 1被生长因子激活，并参与血管平滑肌增殖，而Nox 4似乎调节组成性ROS产生并维持细胞分化。我们认为，虽然Noxl在病理生理情况下被激活，但Nox 4控制细胞的“氧化还原设定点”，并受维持分化表型的激动剂调节。我们有有趣的新的初步数据表明 形态发生蛋白4（BMP 4）可能通过激活Nox 4来防止血小板衍生生长因子（PDGF）诱导的增殖。因此，该项目的总体目标是更好地定义差异调节Nox 1和Nox 4的机制，并确定它们在控制细胞增殖中的对比作用。在目的1中，我们将定义PDGF调节Noxl和Nox 4表达的机制。我们推测PDGF激活的转录机制包括MEF 2诱导Nox 1和ERK 1/2介导的FoxMI激活抑制Nox 4。目的2集中于确定Nox 4的功能作用和Noxl的抑制在BMP介导的血管平滑肌细胞增殖的衰减中。我们的初步数据表明，BMP 4抑制PDGF诱导的增殖，部分是通过 抑制Noxl。BMP 4还增加H2 O2的产生，这使得我们提出它激活Nox 4，导致H2 O2诱导的细胞周期抑制剂p21 - 1的上调。在目标3中，我们计划确定Noxl和Nox 4在侧枝形成中的作用。我们的模型预测Nox 4的表达和活性影响生长因子的反应性，而PDGF诱导的增殖需要Nox 1。在这个目标中，我们将测试这一假设使用生理相关的刺激，缺血诱导侧支形成。最后，在目标4中，我们将确定Nox 4在体内新生内膜形成中的作用。我们假设敲除Nox 4将减少生理上必需的H2 O2产生，并允许Noxl信号传导不受抑制地进行，导致血管损伤后病变形成加剧。这 体外和体内研究的组合将允许我们深入了解Noxl和Nox 4在正常血管功能和血管疾病中的不同和潜在的相反作用。这些研究将提供重要的基础信息，为开发新的治疗方法提供基础，这些新的治疗方法仅针对那些导致病理学的氧化信号传导方面。