Role of Hydrogen Peroxide in the Mechanism of Flow-Induced Dilation of the Human

过氧化氢在人体血流诱发扩张机制中的作用

基本信息

批准号：
7573073
负责人：
David D. Gutterman
金额：
$ 37.94万
依托单位：
MEDICAL COLLEGE OF WISCONSIN
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-01-01 至 2012-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7573073
关键词：
Acids Address Affect Aftercare Animals Arachidonic Acids Arteries Biological Assay Blood Vessels Calcium Cell membrane Cells Cellular Mechanotransduction Chronic Communication Coronary Coronary heart disease Cultured Cells Cyclic GMP Cyclic GMP-Dependent Protein Kinases Cysteine Cytochrome P450 Data Dilator Dimerization Dinoprostone Disulfides Dithiothreitol Dominant-Negative Mutation Electron Transport Endothelial Cells Endothelium Enzymes Event Exposure to Figs - dietary Focal Adhesion Kinase 1 Foundations Generations Goals Guanosine Guanylate kinase Heart Heart Diseases Human Hydrogen Peroxide Laboratories Link Literature Mechanics Mediating Membrane Membrane Potentials Mitochondria Muscle Muscle relaxation phase NADP NADPH Oxidase Nitric Oxide Nitric Oxide Synthase Oxidants Oxidases Oxidation-Reduction Pathway interactions Patients Peptide Signal Sequences Perfusion Physiological Play Potassium Potassium Channel Preparation Process Production Prostaglandins Protein Isoforms Reactive Oxygen Species Reporting Resistance Respiration Respiratory Chain Role Signal Pathway Signal Transduction Small Interfering RNA Smooth Muscle Smooth Muscle Myocytes Source Stress System Techniques Testing Tissues Vascular Smooth Muscle Vasodilation Vasomotor Western Blotting Work arteriole autocrine base catalase clinically relevant feeding gp91ds-tat human AKAP13 protein inhibitor/antagonist novel oxidation paracrine patch clamp prevent public health relevance research study response shear stress vascular bed

项目摘要

DESCRIPTION (provided by applicant): Shear stress acting on endothelial cells produces vasodilation. This is arguably the most important physiological endothelial mechanism of dilation and occurs in virtually every vascular bed. Our recent data indicate that flow-mediated dilation (FMD) occurs in coronary arterioles from patients with coronary disease but operates through a novel mechanism involving endothelial production of reactive oxygen species (ROS) including hydrogen peroxide (H2O2). Surprisingly the mitochondrial respiratory chain plays a necessary role in FMD in the human heart. The overall goal of this application is to examine the FMD signaling sequence from endothelium to smooth muscle studying 3 aims. 1) We will examine the mechanism of endothelial production H2O2. Using fresh human coronary arterioles from subjects with coronary disease and cultured human endothelial cells from both microvascular tissue and conduit arteries for comparison. We shall pursue exciting preliminary data that indicate both mitochondria and NADPH oxidase are involved, possibly through a ROS- induced ROS release mechanism and activation of Rac1. 2) Using a novel bioassay technique to assess vasodilation and smooth muscle potassium channel opening, we shall identify the endothelial derived hyperpolarizing factor (EDHF) responsible for dilation. Both arachidonic acid metabolites and H2O2 are necessary for FMD, but preliminary studies point to H2O2 as the transferable dilator agent. 3) We shall determine the mechanism of H2O2 -induced dilation, examining the novel hypothesis that H2O2 directly acts on PKG11 by cysteine oxidation, yielding an activated disulfide dimeric form of the enzyme. These goals span a broad, clinically relevant redox signaling pathway from endothelial H2O2 formation, to H2O2 release as a transferable vasomotor substance, to its mechanism of action on underlying smooth muscle cells. Collectively these aims address a novel mechanism of endothelium-dependent dilation involving mitochondrial generation of ROS, thus far reported only in human hearts. Results should identify new links among cellular mechanotransduction, respiration, and redox signaling that regulates important physiological events such as arteriolar vasodilation, responsible for tissue perfusion. The direct relevance to humans with chronic coronary disease provides a strong foundation for this mechanistic approach to understanding microvascular reactivity. PUBLIC HEALTH RELEVANCE: Dilation resulting from shear stress acting on endothelial cells is arguably the most important physiological endothelial mechanism of dilation, and occurs in virtually every vascular bed. Although examined extensively in animals, we examine blood vessels directly from humans with heart disease to clarify the mechanisms involved. Our findings show a unique mechanism of dilation involving mitochondrial generation of ROS, thus far reported only in human hearts. Results of this proposal should identify new links among cellular mechanotransduction, respiration, and redox signaling that regulates important physiological events such as arteriolar vasodilation, responsible for tissue perfusion. The direct relevance to humans with chronic coronary disease provides a strong foundation for this mechanistic approach to understanding microvascular reactivity.

描述（由申请人提供）：作用于内皮细胞的剪切应力产生血管舒张。这可以说是最重要的生理性内皮扩张机制，几乎发生在每个血管床中。我们最近的数据表明，血流介导的扩张（FMD）发生在冠状动脉疾病患者的冠状动脉中，但通过一种涉及内皮产生活性氧（ROS）（包括过氧化氢（H2O2））的新机制来发挥作用。令人惊讶的是，线粒体呼吸链在人类心脏的 FMD 中发挥着必要的作用。此应用程序的总体目标是检查从内皮到平滑肌的 FMD 信号序列，研究 3 个目标。 1）我们将研究内皮细胞产生H2O2的机制。使用来自冠状动脉疾病受试者的新鲜人冠状动脉和来自微血管组织和导管动脉的培养人内皮细胞进行比较。我们将追求令人兴奋的初步数据，表明线粒体和 NADPH 氧化酶都参与其中，可能是通过 ROS 诱导的 ROS 释放机制和 Rac1 的激活。 2) 使用新型生物测定技术来评估血管舒张和平滑肌钾通道开放，我们将确定负责扩张的内皮衍生超极化因子（EDHF）。花生四烯酸代谢物和 H2O2 对于 FMD 都是必需的，但初步研究表明 H2O2 是可转移的扩张剂。 3) 我们将确定 H2O2 诱导扩张的机制，检验 H2O2 通过半胱氨酸氧化直接作用于 PKG11 的新假设，产生该酶的活化二硫键二聚体形式。这些目标涵盖了广泛的、临床相关的氧化还原信号通路，从内皮 H2O2 形成，到 H2O2 作为可转移的血管舒缩物质释放，再到其对底层平滑肌细胞的作用机制。总的来说，这些目标解决了一种涉及线粒体生成 ROS 的内皮依赖性扩张的新机制，迄今为止仅在人类心脏中进行了报道。结果应确定细胞机械转导、呼吸和氧化还原信号之间的新联系，这些信号调节重要的生理事件，例如负责组织灌注的小动脉血管舒张。与患有慢性冠心病的人类直接相关，为这种理解微血管反应性的机械方法提供了坚实的基础。公共健康相关性：作用于内皮细胞的剪切应力引起的扩张可以说是最重要的生理性内皮扩张机制，并且几乎发生在每个血管床中。尽管在动物身上进行了广泛的检查，但我们还是直接检查患有心脏病的人的血管，以阐明所涉及的机制。我们的研究结果表明，涉及线粒体生成 ROS 的独特扩张机制，迄今为止仅在人类心脏中报道过。该提案的结果应确定细胞机械转导、呼吸和氧化还原信号之间的新联系，这些信号调节重要的生理事件，例如负责组织灌注的小动脉血管舒张。与患有慢性冠心病的人类直接相关，为这种理解微血管反应性的机械方法提供了坚实的基础。