Extracellular redox biology links to metabolic and mitochondrial dysfunction in pulmonary hypertension

细胞外氧化还原生物学与肺动脉高压的代谢和线粒体功能障碍有关

• 批准号: 10750457
• 负责人: Daniel Antonio Colon Hidalgo
• 金额: $ 6.94万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-02 至 2024-09-01
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10750457
• 关键词: Adenosine Monophosphate; Affinity; Amino Acid Substitution; Animal Model; Attenuated; Automobile Driving; Binding; Bioenergetics; Biogenesis; Biology; Blood Vessels; Cardiac Catheterization Procedures; Cell Hypoxia; Cell Proliferation; Cessation of life; Chronic; Data; Development; Electron Spin Resonance Spectroscopy; Electron Transport; Endothelial Cells; Endothelium; Event; Exposure to; Family; Fatty Acids; Future; Genes; Genus Hippocampus; Goals; Histologic; Homeostasis; Human; Hypoxia; KDR gene; Knowledge; Link; Lung; Measurement; Measures; Metabolic; Metabolic dysfunction; Metabolism; Microscopy; Mitochondria; Modeling; Mouse Strains; Mus; Outcome; Outcome Measure; Oxidation-Reduction; Oxidative Phosphorylation; Pathogenesis; Patients; Phenotype; Physiologic intraventricular pressure; Plasma; Play; Process; Production; Protein Isoforms; Protein Kinase; Pulmonary Hypertension; Pulmonary artery structure; Quality Control; Reactive Oxygen Species; Reporting; Research; Resolution; Respiration; Right Ventricular Function; Role; Severities; Signal Pathway; Signal Transduction; Single Nucleotide Polymorphism; Small Interfering RNA; Smooth Muscle Myocytes; Spectrum Analysis; Spirometry; Superoxide Dismutase; Superoxides; Testing; Therapeutic; Tissues; Variant; Vascular remodeling; Ventricular; Wild Type Mouse; antioxidant enzyme; design; extracellular; fatty acid oxidation; glucose uptake; hemodynamics; human model; hypoxia-induced pulmonary hypertension; in vitro testing; inhibitor; insight; mitochondrial dysfunction; mouse model; novel; oxidation; pharmacologic; premature; pulmonary arterial pressure; right ventricular failure; therapeutically effective

PROJECT SUMMARY/ABSTRACT Despite novel treatments, pulmonary hypertension (PH) represents a progressive, highly morbid, and often fatal condition. Recent studies suggest that metabolic derangements such as the glycolytic switch, ROS production, and mitochondrial dysfunction play a key role in the pathogenesis of PH. Disruptions of ROS homeostasis, primarily regulated by the superoxide (SOD) family, have been associated with PH. Extracellular superoxide dismutase (EC-SOD) is the most prevalent isoform of SOD in the vasculature and has been previously associated with PH in mouse models. In humans, the R213G EC-SOD SNP leads to a reduced matrix binding affinity of EC-SOD, leading to low vascular concentration but higher plasma levels and normal activity. In mice, this SNP has been associated with higher right ventricular pressures at baseline that worsen with hypoxia. Interestingly, these same mice are protected against PH in the Sugen-hypoxia model. We hypothesize that the redistribution of R213G variant of EC-SOD due to its reduced binding affinity will have discrepant effects depending on the model of PH and this effect will be due to distinct model-dependent activation of AMPK and mitochondrial dysfunction in endothelial cells (PAEC) vs. smooth muscle cells (PASMC). Preliminary data demonstrated that at baseline, mice with the R213G EC-SOD variant have significant differences in lung and right ventricular (RV) fatty acid oxidation and electron transport chain activity. To test the effects of loss of vascular EC-SOD in PH, mice with the R213G EC-SOD SNP will be exposed to chronic hypoxia or Sugen-hypoxia to develop pulmonary hypertension, confirmed via invasive hemodynamic and histologic measures (Aim 1). Mitochondrial respiration and ROS production will be measured by high- resolution respirometry and electron paramagnetic resonance, respectively, in whole lung and RV homogenates as well as human pulmonary artery endothelial and smooth muscle cells (Aim 2).

项目概要/摘要 尽管有新的治疗方法，肺动脉高压 (PH) 仍然是一种进行性、高度病态和 通常是致命的情况。最近的研究表明，代谢紊乱，如糖酵解开关、ROS 产生和线粒体功能障碍在 PH 的发病机制中起着关键作用。 ROS 的破坏 主要由超氧化物 (SOD) 家族调节的体内平衡与 PH 相关。 细胞外超氧化物歧化酶 (EC-SOD) 是脉管系统中最常见的 SOD 异构体，具有 先前已在小鼠模型中发现与 PH 相关。在人类中，R213G EC-SOD SNP 会导致 EC-SOD 的基质结合亲和力降低，导致血管浓度较低，但血浆水平较高， 正常活动。在小鼠中，该 SNP 与基线时较高的右心室压力相关。 因缺氧而恶化。有趣的是，这些相同的小鼠在 Sugen 缺氧模型中受到保护，免受 PH 影响。 我们假设 EC-SOD 的 R213G 变体由于其结合亲和力降低而重新分布， 差异效应取决于 PH 模型，并且这种效应将归因于不同的模型依赖 内皮细胞 (PAEC) 与平滑肌细胞中 AMPK 的激活和线粒体功能障碍 （PASMC）。初步数据表明，在基线时，携带 R213G EC-SOD 变体的小鼠具有 肺和右心室（RV）脂肪酸氧化和电子传递链活性存在显着差异。 为了测试 PH 中血管 EC-SOD 损失的影响，将具有 R213G EC-SOD SNP 的小鼠暴露于 慢性缺氧或 Sugen 缺氧导致肺动脉高压，经有创血流动力学证实 和组织学测量（目标 1）。线粒体呼吸和 ROS 产生将通过高 分别在全肺和右心室中进行分辨率呼吸测量和电子顺磁共振 匀浆以及人肺动脉内皮细胞和平滑肌细胞（目标 2）。