Nicotinamide nucleotide transhydrogenase regulates redox balance in atherosclerosis

烟酰胺核苷酸转氢酶调节动脉粥样硬化的氧化还原平衡

• 批准号: 10785854
• 负责人: DAVID M KRZYWANSKI
• 金额: $ 38.5万
• 依托单位: AUGUSTA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10785854
• 关键词: Adhesions; Adipose tissue; Animals; Antioxidants; Aorta; Arterial Fatty Streak; Atherosclerosis; Bioenergetics; Biological Availability; Blood Vessels; CRISPR/Cas technology; Cell Adhesion Molecules; Cell Respiration; Cell physiology; Cells; Clinical; Clinical Trials; Coronary Arteriosclerosis; Data; Development; Diabetes Mellitus; Disease; Endothelial Cells; Endothelium; Enzymes; Equilibrium; Event; Functional disorder; Genes; Glutathione Reductase; Heart failure; High Fat Diet; Human; Hydrogen Peroxide; Hypertension; Impairment; Inflammation; Inflammatory; Knockout Mice; Laboratories; Ligation; Lipids; Lipoproteins; Metabolic Pathway; Metabolism; Mitochondria; Modeling; Modification; Morbidity - disease rate; Mus; NAD(P)+ transhydrogenase; NADH; NADP; NADPH Oxidase; Obesity; Oxidation-Reduction; Patients; Phenotype; Play; Production; Publishing; Reactive Oxygen Species; Regulation; Role; Serum; System; Testing; United States; Vascular Cell Adhesion Molecule-1; Vascular Diseases; Vascular Endothelial Cell; Viral; antioxidant enzyme; antioxidant therapy; aortic arch; catalase; chronic inflammatory disease; endothelial dysfunction; genome wide association study; glutathione peroxidase; in vivo; intercellular cell adhesion molecule; knock-down; mortality; new therapeutic target; novel; obese patients; overexpression; oxidant stress; oxidized low density lipoprotein; preservation; prevent; recruit; response; small hairpin RNA; success; therapeutically effective; trafficking; vascular inflammation

PROJECT ABSTRACT Atherosclerosis, a progressive chronic inflammatory disease of the vessel wall, is regulated by oxidant stress throughout the course of disease development. Endothelial dysfunction is a critical, initiating step in the development of atherosclerosis and increasing evidence implicates mitochondrial reactive oxygen species (ROS) as an important contributor to endothelial dysfunction and vascular inflammation. Nicotinamide nucleotide transhydrogenase (NNT) is emerging as an important enzyme in the regulation of mitochondrial NADPH levels which can have a significant impact on a number of metabolic pathways through the regulation of mitochondrial redox balance. Preliminary data from our laboratory supports this concept demonstrating that NNT expression is reduced in the endothelium of atherosclerotic patients when compared to healthy controls. These data are consistent with previously published data from our laboratory indicating that AAV8-PCSK9 and high fat diet treatment led to increased plaque burden in C57Bl/6J mice that lack NNT. Recent studies utilizing small hairpin RNA knockdown of NNT in human aortic endothelial demonstrates increased hydrogen peroxide production that is associated with reductions in mitochondrial NADPH and impairment of downstream antioxidant enzymes glutathione peroxidase and glutathione reductase. Furthermore, the loss of NNT in these cells also led to increased adhesion molecule expression and inflammatory cell trafficking suggesting that NNT’s role in regulating mitochondrial balance can play a critical role in modulating atherosclerotic plaque development. We have confirmed these observations in vivo using a novel endothelial specific knockout mouse where the loss of NNT promotes enhanced adhesion molecule expression in the aortic arch of mice subjected to AAV8-PCSK9, partial carotid ligation, and high fat diet in a model of disturbed flow induced plaque development. Building upon these findings, we propose that the loss of NNT activity contributes to a pro-oxidative mitochondrial phenotype that exacerbates the progression of atheroscelrosis by enhancing mitochondrial ROS production, endothelial dysfunction, and vascular inflammation . To test this hypothesis, studies are proposed that will determine i) if NNT inhibits mitochondrial ROS production and preserves mitochondrial antioxidant activity and oxidative metabolisim in human vascular endothelial cells; ii) if reduced NNT expression and increased mitochondrial ROS production stimulates Nox activity that contributes to reduced NO bioavailibilty and promotes endothelial activation; and iii) if endothelial NNT critically regulates mitochondrial redox balance and vascular function in mice treated with high fat diet. Data from the proposed studies will identify NNT as a master regulator of mitochondrial function and ROS production whose absence exacerbates the development of atherosclerosis by promoting endothelial dysfunction and vascular inflammation, leading to increased plaque development.

项目摘要 动脉粥样硬化是一种进行性血管壁慢性炎症性疾病，受氧化应激调节 整个疾病发展过程。内皮功能障碍是一个关键的起始步骤 动脉粥样硬化的发展和越来越多的证据表明线粒体活性氧 （ROS）是内皮功能障碍和血管炎症的重要贡献者。烟酰胺核苷酸 转氢酶 (NNT) 正在成为调节线粒体 NADPH 水平的重要酶 它可以通过线粒体的调节对许多代谢途径产生重大影响 氧化还原平衡。我们实验室的初步数据支持这一概念，表明 NNT 表达 与健康对照相比，动脉粥样硬化患者的内皮细胞减少。这些数据是 与我们实验室之前发表的数据一致，表明 AAV8-PCSK9 和高脂肪饮食 治疗导致缺乏 NNT 的 C57Bl/6J 小鼠斑块负担增加。最近的研究利用小发夹 人主动脉内皮细胞中 NNT 的 RNA 敲除表明过氧化氢产量增加， 与线粒体 NADPH 减少和下游抗氧化酶受损有关 谷胱甘肽过氧化物酶和谷胱甘肽还原酶。此外，这些细胞中 NNT 的缺失也导致 粘附分子表达和炎症细胞运输增加表明 NNT 在 调节线粒体平衡可以在调节动脉粥样硬化斑块的发展中发挥关键作用。我们 已经使用新型内皮特异性敲除小鼠在体内证实了这些观察结果，其中 NNT 促进 AAV8-PCSK9 小鼠主动脉弓中粘附分子的表达增强， 部分颈动脉结扎和高脂肪饮食在血流紊乱诱导斑块形成的模型中。建立在 根据这些发现，我们提出 NNT 活性的丧失有助于线粒体的促氧化 通过增强线粒体 ROS 加剧动脉粥样硬化进展的表型 产生、内皮功能障碍和血管炎症。为了检验这一假设，研究人员 提议将确定 i) NNT 是否抑制线粒体 ROS 产生并保护线粒体 人血管内皮细胞的抗氧化活性和氧化代谢； ii) 如果 NNT 表达减少 线粒体 ROS 产生的增加会刺激 Nox 活性，从而降低 NO 生物利用度 并促进内皮细胞活化； iii) 内皮 NNT 是否严格调节线粒体氧化还原平衡 和高脂肪饮食治疗小鼠的血管功能。拟议研究的数据将确定 NNT 是 线粒体功能和 ROS 产生的主要调节因子，其缺失会加剧 通过促进内皮功能障碍和血管炎症导致动脉粥样硬化，导致斑块增加 发展。