Cholesterol Regulation of EGFR-dependent Vasoconstriction in Chronic Hypoxia-induced Pulmonary Hypertension

慢性缺氧引起的肺动脉高压中 EGFR 依赖性血管收缩的胆固醇调节

• 批准号: 10677541
• 负责人: Rosstin Ahmadian
• 金额: $ 1.09万
• 依托单位: UNIVERSITY OF NEW MEXICO HEALTH SCIS CTR
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-01 至 2023-05-12
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10677541
• 关键词: Acute; Address; Affect; Agonist; Altitude; Blood; Blood Vessels; Calcium; Cell membrane; Cell physiology; Cholesterol; Chronic; Chronic Bronchitis; Chronic Obstructive Pulmonary Disease; Clinical; Communication; Coupling; Data; Development; Disease; Distal; Edema; Environment; Epidermal Growth Factor Receptor; Etiology; Goals; Human; Hypoxia; In Vitro; Knowledge; Lead; Lung; Mediating; Mediator; Membrane; Mentors; Mission; Modeling; Molecular; Morbidity - disease rate; National Heart, Lung, and Blood Institute; Oral; Outcome; Pathogenesis; Pathway interactions; Patients; Peripheral; Phenotype; Physicians; Physiology; Preparation; Process; Production; Protocols documentation; Pulmonary Emphysema; Pulmonary Hypertension; Pulmonary Vascular Resistance; Pulmonary artery structure; Rattus; Reactive Oxygen Species; Receptor Signaling; Regulation; Research; Research Training; Scientist; Signal Pathway; Signal Transduction; Sleep Apnea Syndromes; Smooth Muscle Myocytes; Source; Stimulus; Testing; Training; Vasoconstrictor Agents; Video Microscopy; Writing; arterial remodeling; cell type; cellular imaging; constriction; experience; hypoxia-induced pulmonary hypertension; imaging study; in vivo; lung hypoxia; medical schools; mortality; new therapeutic target; novel; oxidation; pressure; pulmonary vasoconstriction; receptor; response; right ventricular failure; skills; vasoconstriction

Project Summary Chronic Hypoxia (CH)-induced pulmonary hypertension (PH) is a significant source of morbidity and mortality in patients with chronic obstructive pulmonary diseases. It is widely recognized that vasoconstriction is a critical mediator of PH, although the mechanisms involved are poorly understood. Our previous studies have demonstrated that enhanced vasoconstrictor sensitivity following CH involves a requisite reduction in pulmonary arterial smooth muscle cell (PASMC) membrane cholesterol content. We have also demonstrated that CH augments vasoconstrictor reactivity by a switch in signaling from primarily calcium-dependent mechanisms to a Ca2+ sensitization pathway that involves the epidermal growth factor receptor (EGFR) and reactive oxygen species (ROS). However, the mechanisms by which CH decreases membrane cholesterol and how this unmasks EGFR-dependent vasoconstriction has yet to be assessed. The proposed studies will investigate the central hypothesis that coupling of vasoconstrictor stimuli to EGFR signaling following CH promotes PASMC hypercontractility through a ROS-dependent decrease in membrane cholesterol. To test this hypothesis, protocols will employ both in vivo and in vitro approaches using a variety of experimental preparations from molecular and single cell imaging studies to video-microscopy of pressurized small pulmonary arteries using a rat model of CH-induced PH. We plan to pursue the following specific aims: Specific Aim 1: Determine the mechanism by which CH decreases PASMC membrane cholesterol. Hypothesis: Elevated ROS production during CH diminishes membrane cholesterol. Specific Aim 2: Determine the mechanism by which decreased PASMC membrane cholesterol augments vasoconstrictor sensitivity following CH. Hypothesis: Decreased PASMC membrane cholesterol in response to CH unmasks EGFR-dependent pulmonary vasoconstriction through regulation of NOX2 and Rac1. The applicant will be immersed in a rich training environment in the Vascular Physiology Group at the UNM School of Medicine through a unique, multi-sponsor mentoring team that will facilitate his research training in defining novel mechanisms by which ROS alter the PASMC membrane microenvironment to affect cellular function in CH-induced PH. The proposed training plan will afford the applicant intensive training experiences in a variety of new experimental approaches, refinement of his oral and written communication skills, and professional development training that will aid him in achieving his goal as an independent, academic physician-scientist in pulmonary research.

项目摘要 慢性缺氧（CH）诱导的肺动脉高压（pH）是发病率的重要来源 慢性阻塞性肺部疾病患者的死亡率。广泛认识到血管收缩 是pH值的关键介体，尽管所涉及的机制知之甚少。我们以前的研究 已经证明，CH后增强的血管收缩敏感性涉及必要的减少 肺动脉平滑肌细胞（PASMC）膜胆固醇含量。我们也证明了 通过从主要依赖钙依赖性的信号传导中的开关来增强血管收缩反应性 涉及表皮生长因子受体（EGFR）的CA2+敏化途径的机制和 活性氧（ROS）。但是，CH降低膜胆固醇的机制和 这如何揭示依赖EGFR的血管收缩尚未评估。 拟议的研究将研究中心假设，即血管收缩刺激偶联到 CH之后的EGFR信号传导通过ROS依赖性降低来促进PASMC的超收缩率 膜胆固醇。为了检验该假设，协议将使用体内和体外方法使用 从分子和单细胞成像研究到视频显微镜的各种实验制剂 使用CH诱导的pH的大鼠模型加压的小肺动脉。 我们计划追求以下具体目标： 具体目标1：确定CH降低PASMC膜胆固醇的机制。 假设：CH期间的ROS产生升高会降低膜胆固醇。 特定目标2：确定降低PASMC膜胆固醇的机制 CH的血管收缩敏感性。 假设：响应于CH的PASMC膜胆固醇降低 通过调节NOX2和RAC1的肺血管收缩。 申请人将沉浸在UNM的血管生理组的丰富培训环境中 医学院通过一个独特的多赞助商指导团队，该团队将促进他的研究培训 定义ROS改变PASMC膜微环境以影响细胞的新机制 CH诱导的pH值。拟议的培训计划将负担申请人的强化培训经验 通过各种新的实验方法，对他的口头和书面沟通技巧的完善，以及 专业发展培训将有助于他实现自己作为独立，学术的目标 肺部研究的医师科学家。