Extracellular superoxide induces Egr-1 in the hypoxic pulmonary artery

细胞外超氧化物在缺氧肺动脉中诱导 Egr-1

基本信息

批准号：
8197441
负责人：
Eva S. Nozik
金额：
$ 38.12万
依托单位：
UNIVERSITY OF COLORADO DENVER
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-12-01 至 2013-08-19
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8197441
关键词：
Animal Model Antioxidants Arteries Automobile Driving Biological Assay Biological Models Blood Blood Vessels Bolus Infusion Bronchopulmonary Dysplasia Cell Count Cell Culture Techniques Cell Proliferation Cell membrane Cells Charge Child Child Development Childhood Chronic Clinical Trials Coagulation Process Collagen Complement Complication DNA Binding Data Deposition Development Employee Strikes Equilibrium Erythropoietin Event Excretory function Exhibits Fibroblasts Foundations Future Gene Expression Genes Genetically Engineered Mouse Goals Grant Growth Hand Health Heart failure Homeostasis Human Hydrogen Peroxide Hypoxia IL8 gene In Vitro Individual Infant Inflammation Injury Intravenous Bolus Kidney Knockout Mice Laboratories Life Lung Lung diseases Measures Medial Membrane Methods Modeling Molecular Morbidity - disease rate Mus Myosin Heavy Chains NADPH Oxidase Neonatal Nuclear Outcome Oxidants Oxidation-Reduction Pathologic Patients Pericytes Phenotype Population Principal Investigator Process Production Property Protein Isoforms Publishing Pulmonary Circulation Pulmonary Hypertension Pulmonary artery structure Pump RNA Reaction Reactive Oxygen Species Reperfusion Therapy Reporter Research Risk Role SOD2 gene Sampling Series Severities Signaling Molecule Smooth Muscle Myocytes Smooth Muscle Myosins Solid Source Stimulus Superoxide Dismutase Superoxides System Tacrolimus Binding Protein 1A Testing Thromboplastin Tissues Tunica Adventitia Up-Regulation Vascular remodeling Wild Type Mouse base cell type extracellular immature animal improved in vivo interstitial knowledge base lung hypoxia lung injury lung ischemia mortality mouse model neonate novel therapeutic intervention overexpression prevent programs promoter protective effect research study response tool transcription factor

项目摘要

DESCRIPTION (provided by applicant): PA vascular remodeling with pulmonary hypertension is a life-threatening complication in infants and children with hypoxic lung diseases. A further understanding of this process is essential to develop new strategies aimed at reducing the severity of pulmonary hypertension in these individuals. Accumulating evidence indicates that reactive oxygen species (ROS), including superoxide (O2-) generated via NADPH oxidase, contribute to vascular remodeling. Extracellular oxidant/antioxidant homeostasis is maintained by the extracellular isoform of superoxide dismutase (EC-SOD), which is highly expressed in the vessel wall. The proposal tests the hypothesis that hypoxia disrupts the balance between the production of extracellular O2- by NADPH oxidase and its clearance by EC-SOD in the PA. We further hypothesize that excess extracellular O2- generated in the hypoxic lung upregulate a hypoxia-inducible and redox-sensitive transcription factor, early growth response-1 (Egr-1), which, in turn, stimulates Egr-1-responsive genes important in causing neonatal chronic hypoxia-induced pulmonary vascular remodeling and pulmonary hypertension. Aim 1 will use PA segments isolated from chronically hypoxic calves and mice and in vitro pulmonary artery vascular cells isolated from the neonatal calf to evaluate production of reactive oxygen species and expression and activity of EC-SOD. Aim 2 will use chronically hypoxic mice overexpressing and lacking EC-SOD as well as mice lacking gp91phox subunit of NADPH oxidase to provide in vivo molecular and pharmacologic evidence that extracellular O2- regulates critical hypoxia-responsive genes and contributes to chronic hypoxia-induced pulmonary vascular remodeling and pulmonary hypertension in the developing lung. To complement this model, in Aim 3, we will use the PA adventitial fibroblast isolated from the neonatal calf as a highly relevant model system for in vitro experiments to test the effects of hypoxia-induced extracellular O2- on the expression of the redox-sensitive transcription factor Egr-1. The study of chronic hypoxia as a stimulus for pulmonary vascular remodeling and pulmonary hypertension is compelling, as hypoxia is a common feature of diverse lung diseases. Thus, by advancing our knowledge base and testing new therapeutic approaches in animal models, we will provide a solid foundation for future human clinical trials in a range of scenarios associated with hypoxic lung diseases to improve health outcome for patients with these difficult and serious problems. PROJECT NARRATIVE: Hypoxia complicates severe lung diseases in infants and children, and the development of pulmonary vascular remodeling and pulmonary hypertension in these patients leads to right heart failure, greatly increasing morbidity and mortality. This proposal tests whether an imbalance in production and clearance of extracellular superoxide contributes to the structural remodeling in chronic hypoxic pulmonary hypertension. This proposal will provide the basis for future human clinical trials in a range of scenarios associated with hypoxic lung diseases to improve health outcome for pediatric patients with these difficult and serious problems.

描述（由申请人提供）：用肺动脉高压进行PA血管重塑是婴儿和缺氧肺部疾病儿童的生命并发症。对这一过程的进一步理解对于制定旨在减少这些个体肺动脉高压严重程度的新策略至关重要。积累的证据表明，活性氧（ROS），包括通过NADPH氧化酶产生的超氧化物（O2-），有助于血管重塑。细胞外氧化剂/抗氧化剂的稳态由超氧化物歧化酶（EC-SOD）的细胞外同工型维持，该同型在容器壁上高度表达。该提案检验了以下假设：缺氧破坏NADPH氧化酶的细胞外O2的产生与PA中EC-SOD的清除之间的平衡。我们进一步假设在低氧肺中产生的过量细胞外O2上调上调低氧诱导和氧化还原敏感的转录因子，早期生长反应1（EGR-1），这反过来刺激EGR-1反应性基因在引起新生儿慢性低氧诱导的肺炎肺动脉炎和pulonary pulonary and pulonary and pulonary and pulonary and pulonary and tulmonary and pulodary and pulonary and pulonary and pulonary and pulonary pulonary pulonary and pulonary pulonary pulonary pulonary and pulonary pulonary。 AIM 1将使用从慢性低氧犊牛和小鼠中分离出的PA段以及从新生小牛分离的体外肺动脉血管细胞来评估活性氧的产生以及EC-SOD的表达和活性。 Aim 2 will use chronically hypoxic mice overexpressing and lacking EC-SOD as well as mice lacking gp91phox subunit of NADPH oxidase to provide in vivo molecular and pharmacologic evidence that extracellular O2- regulates critical hypoxia-responsive genes and contributes to chronic hypoxia-induced pulmonary vascular remodeling and pulmonary hypertension in the developing lung.为了补充该模型，在AIM 3中，我们将使用从新生小牛分离的PA外膜成纤维细胞作为体外实验的高度相关模型系统，以测试缺氧诱导的细胞外O2-对氧化还原敏感转录因子EGR-1表达的影响。慢性缺氧作为肺血管重塑和肺动脉高压的刺激的研究令人信服，因为缺氧是多种肺部疾病的常见特征。因此，通过促进我们的知识库并测试动物模型中的新治疗方法，我们将在与低氧肺部疾病相关的一系列情况下为未来的人类临床试验提供坚实的基础，以改善这些困难和严重问题的患者的健康结果。项目叙述：缺氧使婴儿和儿童的严重肺部疾病复杂化，这些患者的肺血管重塑和肺动脉高压的发展导致心力衰竭，大大增加了发病率和死亡率。该提案测试了生产和清除细胞外超氧化物的失衡是否有助于慢性低氧肺动脉高压的结构重塑。该提案将在与缺氧肺部疾病相关的一系列情况下为未来的人类临床试验提供基础，以改善这些困难和严重问题的小儿患者的健康结果。