ecSOD derived peroxide in pulmonary adaptation to hypoxia

ecSOD 衍生的过氧化物在肺适应缺氧中的作用

基本信息

批准号：
9102162
负责人：
Michael S Wolin
金额：
$ 40.25万
依托单位：
NEW YORK MEDICAL COLLEGE
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-08-16 至 2018-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9102162
关键词：
Acute Animal Model Animals Arteries Attenuated Blood Vessels Cardiopulmonary Chronic Chronic Obstructive Airway Disease Cyclic GMP Cysteine Data Development Dimerization Disease Progression Exposure to Generations Genetic Health Heart failure Human Hydrogen Peroxide Hypoxia In Vitro Information Systems Knock-in Mouse Lung Mediating Modification Mus NOS3 gene Nitric Oxide Oxidation-Reduction Oxygen Peroxides Phosphorylation Process Property Protein Kinase Pulmonary Hypertension Pulmonary artery structure Reactive Oxygen Species Regulation Regulator Genes Relaxation Role Serine Signal Transduction Sleep Apnea Syndromes Smooth Muscle Sulfhydryl Compounds Superoxides System Therapeutic Tissues Vascular Smooth Muscle Work base catalase extracellular heme oxygenase-1 in vivo overexpression oxidation prevent protective effect response src-Family Kinases vasoconstriction

项目摘要

DESCRIPTION (provided by applicant): The central hypothesis of this project is that extracellular SOD (ecSOD) activity has potentially beneficial important roles in controlling the expression of pulmonary hypertension resulting from exposure to chronic hypoxia through the generation of hydrogen peroxide and its stimulation of cGMP protein kinase (PKG). It is also hypothesized that increased expression of ecSOD is a process that contributes to the protective effects of heme oxygenase-1 (HO-1) elevation in pulmonary hypertension. While there is substantial evidence for HO-1 and ecSOD being beneficial in attenuating the development of pulmonary hypertension in several animal models, previous studies do not appear to have considered the mechanisms investigated in this application. Our recent studies document that peroxide can promote activation of PKG by a thiol oxidation-mediated PKG subunit dimerization mechanism which participates in relaxation of pulmonary arteries to extracellular hydrogen peroxide and responses to acute hypoxia. Preliminary data provide evidence that chronic hypoxia in vivo promotes both a dimerization activation of PKG and a suppression of force generation in isolated mouse pulmonary arteries by a process that is reversible by catalase. The studies proposed focus on using mice deficient in ecSOD or HO-1, a PKG knockin mouse that is modified to prevent thiol oxidation-activation of PKG by peroxide together with beneficial pulmonary hypertension therapies that increase ecSOD or HO-1 expression and promote PKG dimerization to investigate their roles in controlling the adaptation of pulmonary vascular function caused by exposure of mice to chronic hypoxia. Studies in Aim 1 define the influence of changes in ecSOD expression on processes contributing to the control of vascular function and remodeling involved in the development and reversal of hypoxia-induced pulmonary hypertension by utilizing mice either overexpressing or deficient in ecSOD. Aim 2 focuses on defining how ecSOD expression functions through either increased peroxide regulation of PKG and/or through increased superoxide scavenging to increase nitric oxide (NO) utilizing PKG knockin mice which have a modification preventing PKG dimerization and mice deficient in endothelial nitric oxide synthase (eNOS). The focus of studies in Aim 3 is defining the influence of changes in ecSOD expression on the protective effects of HO-1 utilizing mice deficient in HO-1 or ecSOD and therapies to induce HO-1 and ecSOD. Studies will include ECHO-Doppler flow analysis of cardiopulmonary function, mechanistic functional studies in isolated pulmonary arteries, signaling studies related to PKG and processes influencing the redox regulation src kinase-mediated STAT-3 phosphorylation promoting expression of miR-204, a master gene regulatory system controlling the development and reversal of smooth muscle remodeling in pulmonary hypertension. These studies should provide definitive new mechanistic information on how the effects of chronic hypoxia promote the development of pulmonary hypertension, which could be beneficial in treating the progression of diseases such as COPD and sleep apnea.

描述（由申请人提供）：该项目的中心假设是，细胞外SOD（ECSOD）活性在控制慢性低氧而导致的慢性缺氧导致的肺动脉高压表达中具有潜在的重要作用，从而通过产生过氧化氢及其刺激CGMP蛋白质激酶（PKG）。还假设ECSOD的表达增加是一种有助于血红素氧酶-1（HO-1）升高的保护作用在肺动脉高压中的过程。尽管有大量证据表明HO-1和ECSOD在几种动物模型中有益于减弱肺动脉高压的发展，但先前的研究似乎并未考虑过此应用中研究的机制。我们最近的研究表明，过氧化氢可以通过硫醇氧化介导的PKG亚基二聚化机制促进PKG，该机制参与了肺动脉弛豫对细胞外氢过氧化氢的放松以及对急性低氧的反应。初步数据提供了证据表明，体内慢性缺氧既促进了PKG的二聚化激活，又通过通过过氧化氧化氢酶可逆的过程来促进分离的小鼠肺动脉中对力的产生抑制。该研究提出的是使用缺乏ECSOD或HO-1的小鼠，这是一种PKG敲击蛋白小鼠，被修饰以防止通过过氧化物通过过氧化物以及有益的肺动脉高压疗法对PKG进行硫醇氧化激活，从而增加Ecsod或HO-1表达，并增加PKG尺寸，并促进其在控制肺炎作用的孔子中，以调查其在孔子中的启动，从而促进了孔子的孔子孔的适应性。 AIM 1中的研究定义了ECSOD表达变化对控制血管功能的控制以及通过利用ECSOD过度表达或不足的小鼠的发育和逆转而导致血管功能和重塑的过程的影响。 AIM 2的重点是定义ECSOD表达如何通过增加PKG的过氧化物调节和/或通过增加的超氧化物清除量来增加使用PKG敲击蛋白小鼠的一氧化氮（NO），从而可以改变PKG二聚化，从而防止PKG二聚体和小鼠缺乏内皮一氧化氮合酶（ENOS）（ENOS）。 AIM 3中的研究重点是定义Ecsod表达变化对HO-1利用HO-1或ECSOD缺乏的小鼠的保护作用的影响，并诱导HO-1和ECSOD。 Studies will include ECHO-Doppler flow analysis of cardiopulmonary function, mechanistic functional studies in isolated pulmonary arteries, signaling studies related to PKG and processes influencing the redox regulation src kinase-mediated STAT-3 phosphorylation promoting expression of miR-204, a master gene regulatory system controlling the development and reversal of smooth muscle remodeling in pulmonary hypertension.这些研究应提供有关慢性缺氧的作用如何促进肺动脉高压的发展的明确的新机械信息，这可能有益于治疗COPD和睡眠呼吸暂停等疾病的进展。