Regulation of pulmonary vascular cell redox state by L-2-hydroxyglutarate

 描述(由申请人提供)：NIH导师临床科学家研究职业发展奖(K08)提案描述了一个为期五年的学术肺部医学职业发展培训计划。首席研究员William Oldham，医学博士，是布里格姆妇女医院(BWH)和哈佛医学院肺部和重症监护医学部的副内科医生和医学讲师。他拥有化学和生物化学背景，并在担任范德比尔特大学NIH医学科学家培训计划成员期间完成了药理学博士研究。2012年，他完成了内科、肺部疾病和重症监护医学的临床培训。他的目标是发展一个成功的职业生涯，成为一名独立资助的内科科学家，研究肺血管疾病的氧化还原代谢。在K08奖项的支持和保护时间下，Oldham博士将从正规课程、独立研究和相关实验技术的实践经验中发展能量代谢、氧化还原生物化学、线粒体生理学和动态建模领域的专业知识。约瑟夫·洛斯卡尔佐博士是国际公认的这些领域的专家，有30多年的指导经验，他将在由新陈代谢和肺部疾病方面的杰出科学家组成的咨询委员会的支持下，指导奥尔德姆博士。随着获奖期的推进，奥德姆博士将培养成功提交R01奖金所需的技能。Oldham博士将在BWH医学部的肺和重症护理医学部工作，这是一个位于哈佛医学院社区中心的杰出的科学和指导环境。每百万人中有15-50人受到肺动脉高压的影响，而肺动脉压力的升高导致数百万受肺病、心力衰竭和其他疾病影响的人的发病率和死亡率增加。PAH的代谢异常为开发这种疾病亟需的疾病调整疗法提供了巨大的潜力。Oldham博士的长期目标是确定PAH背后的代谢紊乱，并针对由此产生的代谢脆弱性开发治疗方法。这项应用的总体目标是确定L2HG在PAH发病机制中的作用，作为迈向他的长期目标的第一步。中心假说是，L2HG的产生通过增加肺血管细胞中促增殖活性氧物质的生成来支持PAH的肺血管重塑。这一建议的基本原理是，一旦确定了L2HG代谢和PAH发病机制之间的联系，这些生化途径就可以被药理学靶向，从而产生治疗PAH的新的和疾病修改的疗法。中心假说将通过追求下列特定目标来验证：(1)使用生化和动力学建模方法确定L2HG代谢、糖酵解和细胞氧化还原状态之间的生化联系；(2)通过对L2HG水平以及细胞增殖、凋亡和活性氧产生的读数的遗传操作来确定L2HG代谢对肺血管细胞表型的影响；以及(3)利用转基因小鼠确定L2HG代谢在PAH发生中的作用。这项工作的贡献有望从机制上理解L2HG代谢如何调节细胞氧化还原动态平衡以支持PAH的肺血管重构。这一贡献将是重要的，因为它将定义L2HG在正常和疾病代谢中的关键作用，这将增强我们对细胞对低氧和其他应激源的反应的理解。这项拟议的研究具有创新性，因为它定义了L2HG代谢在细胞氧化还原动态平衡中的重要作用，从而代表了对现状的新的实质性偏离。这项研究将为细胞内氧化还原信号的研究开辟新的天地。此外，这一途径以前没有与PAH相关，代表了疾病发病机制研究的一个新领域。由于L2HG不是任何已知代谢途径的中间产物，其代谢可能为操纵细胞氧化还原状态提供安全和易处理的实验和治疗靶点，这将为未来对这种致命疾病的研究提供有价值的工具。

 DESCRIPTION (provided by applicant): The NIH Mentored Clinical Scientist Research Career Development Award (K08) proposal describes a five- year training program for career development in academic pulmonary medicine. The principal investigator, William Oldham, M.D., Ph.D., is an Associate Physician and Instructor of Medicine in the Division of Pulmonary and Critical Care Medicine at the Brigham and Women's Hospital (BWH) and Harvard Medical School. He has a background in chemistry and biochemistry and completed doctoral research in pharmacology while a member of the NIH Medical Scientist Training Program at Vanderbilt University. He completed clinical training in Internal Medicine, Pulmonary Disease, and Critical Care Medicine in 2012. His goal is to develop a successful career as an independently funded physician-scientist investigating redox metabolism in pulmonary vascular disease. With the support and protected time provided by the K08 award, Dr. Oldham will develop expertise in the fields of energy metabolism, redox biochemistry, mitochondrial physiology, and dynamic modeling from formal coursework, independent study, and practical experience with relevant experimental techniques. Dr. Joseph Loscalzo, an internationally recognized expert in these areas with over 30 years of mentoring experience, will mentor Dr. Oldham with the support of an advisory committee composed of outstanding scientists in metabolism and pulmonary disease. As the award period progresses, Dr. Oldham will develop the skills necessary for a successful R01 grant submission. Dr. Oldham will work in the Division of Pulmonary and Critical Care Medicine in the Department of Medicine at BWH, an outstanding scientific and mentoring environment located within the heart of the Harvard Medical School community. Pulmonary arterial hypertension affects 15-50 people per million and elevated pulmonary artery pressures con- tribute to increased morbidity and mortality of millions more affected by lung disease, heart failure, and other conditions. Metabolic abnormalities in PAH offer a rich potential for the development of much-needed disease modifying therapies for this condition. Dr. Oldham's long-term goal is to define the metabolic derangements underlying PAH and to develop therapies targeting the resulting metabolic vulnerabilities. The overall objective of this application is to define the role of L2HG in the pathogenesis of PAH as the first step toward his long- term goal. The central hypothesis is that L2HG production supports pulmonary vascular remodeling in PAH by increasing pro-proliferative reactive oxygen species generation in pulmonary vascular cells. The rationale for this proposal is that, once the links between L2HG metabolism and PAH pathogenesis are defined, these bio- chemical pathways can be targeted pharmacologically, resulting in novel and disease-modifying therapies for PAH. The central hypothesis will be tested by pursuing the following specific aims: (1) Determine the biochemical link between L2HG metabolism, glycolysis, and cellular redox state using biochemical and kinetic modeling approaches; (2) Determine the impact of L2HG metabolism on pulmonary vascular cell phenotype using genetic manipulations of L2HG levels and readouts of cell proliferation, apoptosis, and reactive oxygen species production; and (3) Determine the role of L2HG metabolism in the development of PAH using genetically modified mice. The contribution of this work is expected to be a mechanistic understanding of how L2HG metabolism regulates cellular redox homeostasis in support of pulmonary vascular remodeling in PAH. This contribution will be significant because it will define a critical role for L2HG in normal and diseased metabolism that will enhance our understanding of the cellular response to hypoxia and other stressors. The proposed research is innovative because it represents a new and substantive departure from the status quo by defining an important role for L2HG metabolism in cellular redox homeostasis. This research will open new horizons in the study of intracellular redox signaling. Moreover, this pathway has not been previously associated with PAH and represents a new area for mechanistic investigations of disease pathogenesis. Since L2HG is not an intermediate in any known metabolic pathway, its metabolism may offer safe and tractable experimental and therapeutic tar- gets for manipulating cellular redox state, which would provide a valuable tool for future investigations of this deadly disease.