Carbon Monoxide Inhibition of Mitochondrial Function and Efficacy of a Novel Antidotal Therapeutic for Carbon Monoxide Poisoning

 描述(申请人提供)：一氧化碳(CO)接触是美国人类中毒的主要原因，每年有50,000例。目前的治疗方法，常压氧或高压氧，疗效有限，难以提供。目前还没有解毒剂疗法。我们对一氧化碳的毒性作用有两方面的理解：一氧化碳直接与血红蛋白结合，降低血液的携氧能力，一氧化碳直接与细胞色素c氧化酶中的血红素结合，抑制线粒体的呼吸。CO中毒的主要后遗症-心血管功能障碍和急性和长期神经功能障碍-依赖于线粒体功能受损。我们实验室已经开发出一种对一氧化碳具有非常高亲和力的试剂，重组人脑红蛋白(RNgb)，它有可能减少一氧化碳中毒的毒性效应。因此，我们提出假设，用rNgb治疗可以逆转CO中毒对线粒体功能的毒性效应。为了验证这一假说，我们将首先使用类似Clark的电极进行体外研究，以进一步表征CO对分离的线粒体和心脏组织呼吸的毒性效应，并证明rNgb可以逆转CO对线粒体呼吸的毒性效应。其次，在体内CO中毒模型中，我们将显示rNgb治疗可以逆转通过功能MRI变化(分数各向异性)以及血乳酸和血糖水平评估的病理变化。这些结果将为rNgb作为一种潜在的CO中毒治疗剂提供临床前的概念证明。与此同时，通过NIH Smartt计划，我们正在进行药理学和毒理学测试，并扩大药物制造能力。NRSA奖将使我作为一名接受过肺部和重症监护培训的研究员，获得一个独特的机会，利用我的导师Mark Gladwin博士现有的研发基础设施，获得关于疾病动物模型、线粒体生物学和病理生理结果的高级培训。此外，我正在卡内基梅隆大学泰珀商学院攻读创业MBA课程，该课程将提供金融、统计建模和关键工具方面的广泛培训，以将一种潜在的治疗药物从工作台带到床边。我的导师格拉德温博士是一氧化氮和珠蛋白生物化学方面的专家，以及药物从实验室到临床的翻译开发方面的专家，我的导师格拉德温博士和我的同事导师希瓦博士是线粒体生物学专家，加上匹兹堡大学提供的大量资源，将使我能够开发新的翻译研究技能，特别是开发新的治疗策略。

 DESCRIPTION (provided by applicant): Carbon monoxide (CO) exposure is the leading cause of human poisoning in the United States, with 50,000 cases every year. Current therapy, normobaric or hyperbaric oxygen, has limited effectiveness and is difficult to deliver. There is currently no antidotal therapy. Our understanding of the toxic effects of CO is two-fold: CO directly binds to hemoglobin reducing oxygen carrying capacity of the blood, and CO directly binds to a heme in cytochrome c oxidase, inhibiting mitochondrial respiration. The major sequelae of CO poisoning - cardiovascular dysfunction and acute and long term neurologic deficits - are dependent on impaired mitochondrial function. Our lab has developed an agent, recombinant human neuroglobin (rNgb), with a very high affinity for CO, which has the potential to reduce the toxic effects of CO poisoning. We, therefore, propose the hypothesis that treatment with rNgb reverses the toxic effects of CO poisoning on mitochondrial function. To test the hypothesis, we will first conduct in vitro studies using a Clark-like electrode to further characterize the toxic effects of CO on isolated mitochondria and heart tissue respiration and demonstrate that rNgb can reverse the toxic effects of CO on mitochondrial respiration. Second, in an in vivo CO poisoning model, we will show that treatment with rNgb can reverse pathologic changes as assessed by functional MRI changes (fractional anisotropy) and blood levels of lactate and glucose. These results will provide pre-clinical proof of concept for rNgb to act as a potential therapeutic agent in CO poisoning. In parallel, through the NIH SMARTT program we are conducting pharmacology and toxicology testing and scaling up drug manufacturing capabilities. The NRSA award will allow me, a pulmonary and critical care trained fellow, a unique opportunity to leverage the existing research and development infrastructure of my mentor, Dr. Mark Gladwin, to gain advanced training in animal models of disease, mitochondrial biology, and pathophysiologic outcomes. In addition, I am pursuing an MBA in the entrepreneurial track at the Tepper School of Business at Carnegie Mellon University, which will provide extensive training in finance, statistical modeling, and critical tools for bringing a potential therapeutic drug from bench to bedside. The resources and experience of my mentor Dr Gladwin, an expert in NO and globin biochemistry, as well as the translational development of drugs from the laboratory to the clinic, and my co- mentor Dr Shiva, an expert in mitochondrial biology, combined with the expansive array of resources available at the University of Pittsburgh, will allow me develop new translational research skills with a specific focus on development of novel therapeutic strategies.