Period in Cardio Protection

描述（由申请人提供）：这个为期5年的培训计划提出了在心肌缺血和心脏生物学领域成为独立生物医学研究人员的职业发展计划。首席研究员是委员会认证的麻醉师，并完成了重症监护奖学金培训。在赞助商和经验丰富的合作者的帮助下，他将扩展自己的科学技能，为作为一名独立的内科科学家的职业发展做准备。该计划将强调细胞内途径的分子生物学技能，在肌细胞功能和缺血适应过程的调节中使用体外（暴露于缺氧的分离肌细胞）和体内（小鼠原位心肌缺血）模型。为了提高他在代谢生物学方面的知识，他将参加丹佛国家犹太医学中心组学技术项目提供的课程。Thomas Henthorn医学博士，部门负责人将提供赞助。Holger Eltzschig医学博士，器官缺氧和缺血分子生物学的国际专家，将成为专门的导师并提供赞助。该项目将受益于sean Colgan博士的专业知识合作，Sean Colgan博士是导致缺氧适应的分子机制的世界专家，他将为细胞内途径，翻译后机制和代谢研究提供咨询支持。此外，Peter Buttrick医学博士和Michael Bristow医学博士都是世界知名的心脏病专家，他们将与dr。埃尔茨希格和科尔根每16周参加一次咨询委员会。该委员会将审查进展情况，并提供密切的科学支持和职业建议。心肌缺血（MI）是一个永久性和严重的医学问题。在过去的几十年里，令人信服的证据已经证明了腺苷的产生在心脏缺血预处理（IP）信号传导中的核心作用，这种现象被认为是抗心肌缺血的最强体内保护形式。因此，许多可能的效应物已被确定为介导心脏IP的关键。然而，IP发起的途径是完全未知的。在这项研究中，我们展示了来自微阵列的数据，其中我们鉴定了两个昼夜节律蛋白，周期1和周期2，作为腺苷依赖分子。在后者中，我们可以确认这两种节律蛋白的诱导和稳定依赖于IP和腺苷。在Per2-/-小鼠中进行的后续研究揭示了周期在IP和心脏缺血中的功能作用。Per2-/-小鼠梗死面积增大，IP介导的心脏保护作用消失。由于已知昼夜节律蛋白在代谢过程中起主导作用，并被报道控制线粒体代谢，我们下一步研究线粒体中主要的耗氧酶，ATP合酶。我们发现这种酶在野生型中由于IP而下调，但在月经不足小鼠中没有下调。基于这些发现，我们假设经期介导代谢组织适应，这是心脏IP的核心。为了研究经期在心肌梗死中的新作用，我们设计了三个具体目标：(1)在第一个目标中，我们建议结合药理学和遗传学方法研究经期稳定的体外调节机制和后果。(2)在第二个目标中，我们将结合体外和体内研究来研究由周期稳定引发的代谢途径。在第三个目标中，通过使用组织特异性小鼠进行周期研究，我们将首先阐明内皮细胞和心肌细胞在体内对心肌梗死的个体贡献。最后，我们将把心脏期作为强光照射治疗心肌梗死的治疗选择。这些研究旨在揭示心肌梗死期间调节细胞损伤的内源性途径。靶向这些途径将为心肌梗死治疗的新型和特异性治疗方法奠定基础，这是迫切需要的，以提高发病率和死亡率。

DESCRIPTION (provided by applicant): This 5-year training program proposes the development plan for a career as an independent biomedical researcher in the area of myocardial ischemia and cardiac biology. The principal investigator, is a board certified Anesthesiologist and has completed a Critical Care Fellowship training. With the sponsors and experienced collaborators he will expand on his scientific skills in preparation for career progression as an independent physician-scientist. The program will emphasize skills in molecular biology of intracellular pathways in myocyte function and regulation of ischemia- adaptive processes using in vitro (isolated myocytes exposed to hypoxia) and in vivo (murine in situ myocardial ischemia) models. To advance his knowledge in metabolic biology he will attend courses offered by the Omics Technologies Program at the National Jewish, Denver. Thomas Henthorn, MD, the Departmental Head will provide sponsorship. Holger Eltzschig MD, PhD, an international expert in molecular biology of organ hypoxia and ischemia will be the dedicated mentor and provide sponsorship. The program will benefit from collaborative expertise of Sean Colgan PhD, a world expert in molecular mechanisms leading to adaptation to hypoxia, who will provide consultative support for the studies on intracellular pathways, posttranslational mechanisms and metabolic studies. Additionally, Peter Buttrick, MD and Michael Bristow MD, PhD, both world renowned cardiologists, will collaborate and serve with Drs. Eltzschig and Colgan on an advisory committee every 16 weeks. This committee will review progress and provide close scientific support and career advice. Myocardial ischemia (MI) is a permanent and serious medical problem. Over the last decades, convincing evidence has demonstrated a central role of adenosine generation in signaling in cardiac ischemic preconditioning (IP), a phenomenon known as the strongest in vivo-form of protection against myocardial ischemia. As such, many possible effectors have been identified to be critical for mediating IP of the heart. However, the pathway initiated by IP is completely unknown. In this study, we present data from a microarray where we identified two circadian rhythm proteins, Period 1 and Period 2, as adenosine dependant molecules. In the latter we could confirm an IP and adenosine dependant induction and stabilization of these two rhythm proteins. Following studies in Per2-/- mice revealed a functional role of Period in IP and ischemia of the heart. Per2-/- mice had bigger infarct sizes and abolished cardioprotection mediated by IP. Since circadian rhythm proteins are known to play a dominant role in metabolic processes and are reported to control mitochondrial metabolism, we next pursued studies on the main oxygen consuming enzyme in mitochondria, the ATP Synthase. We found that this enzyme was downregulated due to IP in wildtype, but not in Period deficient mice. Based on these findings we hypothesize that Periods mediate metabolic tissue adaptation which is central to cardiac IP. Three specific aims were designed to address novel roles for Period in MI. (1) In the first aim, we propose to study regulatory mechanisms and consequences of Period stabilization in vitro by combining pharmacological and genetic approaches. (2) In the second aim, we will combine in vitro and in vivo studies to investigate metabolic pathways initiated by period stabilization. In the third aim, by utilizing tissue specific mice for Period, we will first elucidate the individual contribution of endothelium and cardiomyocytes to MI in vivo. Finally, we will target Period in the heart as therapeutic option to treat MI using intense light exposure. These studies are designed to shed new light on endogenous pathways that regulate cell injury during MI. Targeting such pathways will lay the groundwork for novel and specific therapeutic approaches in the treatment of MI, which are urgently needed to improve morbidity and mortality. PUBLIC HEALTH RELEVANCE: Title Period in Cardioprotection Narrative These studies will lay the groundwork for novel and specific therapeutic approaches in the treatment of myocardial ischemia.