Aldosterone impairs endothelin B-dependent synthesis of nitric oxide to promote p

描述（由申请人提供）：NIH指导临床科学家研究职业发展奖提案描述了学术心血管医学职业发展的5年培训计划。首席研究员（PI）完成了博士后基础科学研究奖学金（2005-2008），并于2011年7月加入布里格姆妇女医院/哈佛医学院心血管医学部（BWH/HMS）。PI继续进行一项深入的研究计划（2010-），旨在促进作为心血管疾病独立科学家的职业生涯。该研究计划为PI在细胞生物学、液相色谱-质谱（LC-MS）和体内心肺血流动力学评估方面提供了严格的经验。Drs。Joseph Loscalzo和Jane Leopold将在此期间指导PI的科学发展。Loscalzo博士是国际公认的氧化还原生物学和肺动脉高压（PAH）领域的领导者，他在指导成功的年轻医生科学家方面拥有丰富的经验。利奥波德博士是医学副教授（HMS）和醛固酮（ALDO）介导的血管功能障碍领域的专家，在指导方面有着良好的记录。本研究拟从氧化还原生化角度探讨ALDO在PAH肺血管功能障碍发生中的作用；因此，该提案的共同指导只适合PI。洛斯卡佐/利奥波德心血管研究实验室（BWH/HMS）是该项目的场地，拥有良好的环境和必要的资源，以确保PI成功实现学术医学的独立性。

DESCRIPTION (provided by applicant): The NIH Mentored Clinical Scientist Research Career Development Award proposal describes a 5-year training program for career development in academic cardiovascular medicine. The principal investigator (PI) completed a postdoctoral basic science research fellowship (2005-2008) and in July 2011 joined as Faculty in the Division of Cardiovascular Medicine at Brigham and Women's Hospital/Harvard Medical School (BWH/HMS). The PI continues an intensive research program (2010- ) designed to promote a career as an independent scientist in cardiovascular diseases. The proposed research plan affords the PI rigorous experience in cell biology, liquid chromatography-mass spectrometry (LC-MS), and cardiopulmonary hemodynamic assessment in vivo. Drs. Joseph Loscalzo and Jane Leopold will mentor the PI's scientific development during this period. Dr. Loscalzo is an internationally recognized leader in the fields of redox biology and pulmonary arterial hypertension (PAH), who has vast experience in mentoring successfully young physician-scientists. Dr. Leopold is an Associate Professor of Medicine (HMS) and an expert in the field of aldosterone (ALDO)-mediated vascular dysfunction, with a strong track record in mentorship. This proposal focuses on redox biochemistry to investigate the contribution of ALDO to the development of pulmonary vascular dysfunction in PAH; thus, co-mentorship for this proposal is uniquely suited for the PI. The Loscalzo/Leopold Cardiovascular Research Laboratory (BWH/HMS) is the site for this project and an excellent environment with the necessary resources to ensure the PI's success for achieving independence in academic medicine. PAH is a fatal disease characterized by increased pulmonary vascular endothelial reactive oxygen species (ROS) formation, decreased levels of bioavailable nitric oxide (NO.), and impaired pulmonary endothelium-dependent vasodilation. ROS-mediated modifications in the redox state of functionally essential protein cysteinyl thiols involved in NO. signaling may affect adversely vascular tone. In human pulmonary artery endothelial cells (HPAECs), endothelin- B (ETB) receptor Cys405 is functionally linked to activation of endothelial nitric oxide synthase by ETB to generate NO.. Here, we provide novel evidence to demonstrate that hyperALDO is present in PAH in vivo, which increases ROS levels in HPAECs to induce ETB disulfide bond/sulfenic acid formation and decrease ETB-dependent NO. synthesis. Thus, the central hypothesis of this proposal is that: In PAH, oxidative modification of Cys405 by hyperALDO- induced ROS formation acts as a molecular "switch" to disrupt ETB-dependent NO. generation and impair pulmonary vasodilation. The specific aims are: (1) investigate the functional effects of ALDO-induced ETB cysteinyl thiol oxidative modification(s) in vitro; (2a) determine the contribution of hyperALDO to impaired pulmonary vascular reactivity in PAH in vivo; and (2b) investigate the therapeutic effects of ALDO antagonism for PAH in vivo. We will use two different models of PAH in rats in vivo and LC-MS to identify ETB cysteinyl thiol oxidation product(s). These studies aim to identify novel treatment targets for PAH and other vascular diseases with similar pathobiology.