TRP Channels In The Regulation of Vascular Tone

TRP 调节血管张力的通道

• 批准号: 9027265
• 负责人: David X. Zhang
• 金额: $ 37.06万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-02-04 至 2020-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9027265
• 关键词: Acute; Address; Agonist; Allosteric Regulation; Angiotensin II; Animal Disease Models; Arachidonic Acids; Atherosclerosis; Binding; Binding Sites; Biochemical; Biological Assay; Blood Vessels; Cause of Death; Clinical Trials; Coronary; Coronary Arteriosclerosis; Coronary Vessels; Coronary artery; Data; Dilator; Disease; Endothelial Cells; Endothelium; Enzymes; Epoprostenol; Equilibrium; Etiology; Figs - dietary; Functional disorder; Funding; Genes; Genetically Engineered Mouse; Goals; Health; Homeostasis; Human; Hydrogen Peroxide; Image; In Vitro; Inflammatory; Knock-out; Ligand Binding; Mediating; Mediator of activation protein; Membrane; Methods; Microcirculation; Microvascular Dysfunction; Molecular; Mus; Mutagenesis; Myocardial Ischemia; Nitric Oxide; Oxidation-Reduction; Oxidative Stress; Pathway interactions; Patient-Focused Outcomes; Phosphorylation; Physiological; Play; Process; Production; Prostaglandins I; Protein Overexpression; Proteins; Publishing; Reactive Oxygen Species; Regulation; Risk Factors; Rodent; Role; Signal Pathway; Signal Transduction; Single base substitution; Stimulus; TRP channel; Techniques; Testing; Transcript; Vanilloid; Vascular Diseases; Vasodilation; Vasodilator Agents; Vasomotor; Woman; Work; arachidonate; arteriole; endothelial dysfunction; human data; improved; in vivo; innovation; insight; men; mutant; new therapeutic target; novel; patch clamp; prevent; protein expression; public health relevance; receptor; release factor; success; vascular factor

 DESCRIPTION (provided by applicant): Vascular homeostasis is critically dependent upon factors released from the endothelium, the most prominent of which are nitric oxide (NO), prostacyclin (PGI2), and a class of endothelium-derived hyperpolarizing factors. The presence of vascular disease and its risk factors can change the balance of these endothelial factors. Our previous studies have demonstrated that such a change in human coronary arterioles (HCAs) from subjects with coronary artery disease (CAD), where the physiological stimulus of laminar flow or shear induces endothelial production of hydrogen peroxide (H2O2) to elicit dilation; in the absence of disease, however, the same stimulus releases NO as the main dilator factor. How shear induces the release of two distinct factors in flow-mediated dilation (FMD) remains incompletely understood. While both H2O2 and NO dilate HCAs, each has different or opposing non-vasomotor effects on vessel wall homeostasis and propensity for atherosclerosis. The overall goal of this project is to elucidate the intracellular pathways responsible for the releaseof these two mediators of FMD, expanding upon published and preliminary data indicating a crucial role for transient receptor potential vanilloid (TRPV) channels in endothelial production o vasodilator factors. The overall hypothesis of this proposal is that FMD of HCAs involves a functional switch of TRPV channels from health (TRPV1/2; TRPV type 1 and 2) to disease (TRPV4; TRPV type 4). As a result of this switch, the mediator of dilation changes from NO to H2O2. We propose three specific aims to test this hypothesis. Aim 1 will determine the spectrum of endothelial TRPV channel involvement in FMD of coronary arteries in the absence and presence of CAD. Aim 2 attempts to define the signaling pathways responsible for flow-induced TRPV activation and production of disparate endothelial dilator factors in non-CAD versus CAD. We will pursue preliminary data suggesting that arachidonic acid (AA) serves as an endogenous activator of TRPV4 in FMD of HCAs, likely via a potentially novel arachidonate recognition sequence (ARS) on TRPV4 protein. We will also test the innovative hypothesis that NO- and H2O2-mediated allosteric regulation of TRPV channels reinforces two distinct pathways of vasodilator release in non-CAD versus CAD. Finally, aim 3 will determine whether TRPV4 serves as a molecular switch contributing to the change of endothelial dilator factors and redox balance. Studies will be conducted on freshly isolated human coronary vessels and endothelial cells using a multifaceted approach incorporating isolated vessel reactivity, Ca2+ imaging, patch-clamping recording of TRP channel activity, biochemical methods such as ligand binding assays, and molecular techniques including gene overexpression and protein mutagenesis. Genetically engineered mice will also be used to corroborate human data and to support causality and in vivo significance. We expect that success of the proposed work will provide new translational and mechanistic insights into the pathways responsible for the transition of dilator factors and vascular oxidative stress in CAD and impact our understanding of coronary atherosclerosis.

 描述（由适用提供）：血管内稳态严重取决于从森植物中释放的因素，其中最突出的是一氧化氮（NO），前列腺素克蛋白（PGI2）和一类佛经室衍生的高丙基化因子。血管疾病及其危险因素的存在可能会改变这些原始因素的平衡。我们先前的研究表明，人类冠状动脉（HCA）的这种变化来自患有冠状动脉疾病（CAD）的受试者，其中层流或剪切的物理刺激会诱导过氧化氢（H2O2）的内皮产生以引起词典。然而，在没有疾病的情况下，相同的刺激释放为NO与主要扩张因子。剪切如何在流介导的字典（FMD）中释放两个不同因素的释放尚不完全理解。虽然H2O2和无扩张性HCA都对血管壁体内平衡和对动脉粥样硬化的有望有不同或相反的非杂肌影响。该项目的总体目标是阐明负责释放这两个FMD的介体的细胞内途径，并根据已发表和初步数据扩展，这表明对瞬态受体电位香草素（TRPV）通道至关重要，在内皮产生O adsodiLator因子中。该提案的总体假设是HCA的FMD涉及从健康（TRPV1/2； TRPV类型1和2）转换为疾病（TRPV4; TRPV4; TRPV类型4）的TRPV通道的功能转换。由于此开关的结果，扩散的介体从NO变为H2O2。我们提出了三个特定的目的来检验这一假设。 AIM 1将在不存在和存在CAD的情况下确定内皮TRPV通道在冠状动脉FMD中的范围。 AIM 2尝试定义负责流量引起的TRPV激活和非CAD与CAD中不同内皮扩张因子的产生的信号传导途径。我们将追求初步数据，表明蛛网膜酸（AA）是HCAS FMD中TRPV4的内源性激活剂，这可能是通过TRPV4蛋白上潜在的新型蛛网膜识别序列（ARS）。我们还将测试创新的假设，即NO-和H2O2介导的TRPV通道的变构调节加强了在非CAD与CAD中血管舒张释放的两种不同的途径。最后，AIM 3将确定TRPV4是否充当分子开关，导致内皮扩张因子变化和氧化还原平衡。研究将使用新鲜分离的人类冠状动脉血管和内皮细胞进行多方面的方法，该方法结合了孤立的血管反应性，CA2+成像，TRP通道活性的斑块夹记录，生化方法，例如配体结合分析以及分子技术等生化方法，包括基因过表达和蛋白质毒素。基因工程小鼠还将用于证实人类数据并支持因果关系和体内意义。我们期望拟议的工作的成功将为CAD中扩张剂因子过渡和血管氧化应激的途径提供新的翻译和机械见解，并影响我们对冠状动脉粥样硬化的理解。