Hypothermia for Cardiac Arrest: Optimizing Akt-Nitric Oxide Synthase Signaling

描述（由申请人提供）：该提案是候选人在急诊医学和生物医学工程方面背景的自然延伸。他独特的背景和对转化科学的热情已经为动物复苏研究做出了贡献。这项创新的工作模拟了我们的患者早期心脏骤停后再灌注损伤，即尽管初始自发循环（ROSC）恢复，但心血管衰竭。该培训计划将通过正式培训申请人在一氧化氮信号和解耦研究的最佳分子生物学方法来增强已经完成的小鼠建模。申请人将受益于急诊复苏中心的多学科指导，建立在心脏氧化损伤和适应以及自由基生物学的专业知识基础上。赞助商dr。范登·霍克和麦克纳利都是经验丰富的内科科学家。他们也对心肌细胞和小鼠模型中氧化介导的心脏收缩功能障碍和死亡感兴趣。这个职业发展项目建立在申请人的优势、培训计划和机构支持和指导的基础上。我们假设心脏骤停后的保护性低温增加了akt相关的组成型一氧化氮合酶（cNOS） no信号，同时减弱了cNOS解偶联和破坏性活性氧（ROS）的产生。具体而言，在心脏骤停小鼠模型中，我们将：（目标1）基于心脏Akt和cNOS活性优化保护性低温的目标温度；（目的2）通过选择性抑制和敲除策略，检验NOS1/NOS3在心脏骤停后损伤、NO和ROS生成以及低温保护中的相对重要性；和（目标3）。检验NOS底物/辅因子补充策略能否重现低温保护作用。芝加哥大学医学系和急诊医学部在利用K08医师-科学家培训项目进行指导方面有着成功的记录。拟议的培训将为Beiser博士提供额外的技能，使其成为该领域领先的独立内科科学家。从一个外行人的角度来看，心脏骤停（当心脏停止跳动时）与电视或电影中描述的不同——大多数最初复苏的人都没有活下来。这项工作将有助于理解为什么给身体降温几度实际上会增加一种氧化应激，从而帮助身体自愈。

DESCRIPTION (provided by applicant): This proposal is a natural extension of the candidate's background in Emergency Medicine and Biomedical Engineering. His unique background and passion for translational science has already contributed to animal resuscitation research. This innovative work models early post-cardiac arrest reperfusion injury in our patients, i.e. cardiovascular collapse despite initial return of spontaneous circulation (ROSC). The training program will enhance the mouse modeling already done by formally training the applicant in the best molecular biology approaches for study of nitric oxide signaling and uncoupling. The applicant will benefit from multi-disciplinary mentorship within the Emergency Resuscitation Center, building upon expertise in heart oxidant injury and adaptation, and free radical biology. The sponsors Drs. Vanden Hoek and McNally are experienced physician-scientists. They are also collaborators interested in oxidantmediated heart contractile dysfunction and death in cardiomyocyte and mouse models. This Career Development Project builds upon the strengths of the applicant, the training program and institutional support and mentorship. We hypothesize that protective hypothermia following cardiac arrest increases Akt-related constitutive nitric oxide synthase (cNOS) NO-signaling, while attenuating cNOS uncoupling and generation of damaging reactive oxygen species (ROS). Specifically, in a mouse model of cardiac arrest we will: (Aim 1) Optimize the target temperature of protective hypothermia based on heart Akt and cNOS activity; (Aim 2) Test the relative importance of NOS1/NOS3 in post-cardiac arrest injury, NO and ROS generation, and hypothermia protection using selective-inhibitor and knockout strategies; and (Aim 3). Test whether hypothermia protection can be reproduced by NOS substrate/cofactor repletion strategies. The University of Chicago Department of Medicine and Section of Emergency Medicine have a track-record of successful mentoring using the K08 physician-scientist training program. The proposed training will provide Dr. Beiser with additional skills to become a leading independent physician-scientist in his field. From a layperson perspective, cardiac arrest (when the heart stops) is different than depicted on TV or the movies-most people initially resuscitated do not survive. This work will help understand how cooling the body a few degrees can actually increase a type of oxidant stress that helps the body heal itself.