Peptide-Mediated Enhancement of Akt During Resuscitation and Reperfusion

项目摘要/摘要 院外心脏骤停是一个重大的公共卫生负担，每年影响到超过35万人。 美国。存活率仍然不到12%，长期神经缺陷在幸存者中很常见。 目前还没有药物可以逆转心肌顿抑或改善神经系统良好的长期存活率。 结果，这突出了复苏方面的迫切和未得到满足的需求。心脏的药理刺激 葡萄糖氧化是促进恢复和逆转病理改变的潜在关键策略 缺血后发生的脂肪酸氧化增加，尽管二氯乙酸酯等药物有限 通过毒性。一种新的细胞穿透肽TAT-PHLPP9c被开发出来，它能迅速进入组织 并选择性地抑制PHLPP1，从而增强Akt的激活。在心脏骤停的小鼠模型中， 心肺复苏期间静脉应用TAT-PHLPP9c促进脑血流恢复 心脏和大脑中Akt和丙酮酸脱氢酶的激活。在猪体内，给药的TAT- 机械心肺复苏期间PHLPP9c显著提高24小时存活率。TAT-PHLPP9c等代理 快速获得组织以提高存活率将代表着复苏方面的重大进步。 使用TAT-PHLPP9c靶向代谢功能障碍可能会降低成功所需的回路流速 ECPR，这将允许使用狭窄的插管，并可能导致更广泛的ECPR。使用高 分辨率磁共振方法，本项目将研究TAT-PHLPP9c的机制 心脏保护和神经保护。将检验以下假设：1)TAT-PHLPP9c直接靶标 2)TAT-PHLPP9c可减少心肌细胞的脂肪酸氧化。 3)低流量心肺复苏期间应用TAT-PHLPP9c可提高心脏骤停存活率， 神经功能恢复、脑血流量和脑代谢；4)TAT-PHLPP9c减少电路流量 ECPR成功率；5)TAT-PHLPP9c介导的外周血白细胞Akt激活 反映来自重要器官的组织中Akt的激活。这些假说将使用朗宁多夫模型进行检验。 大鼠心脏缺血/再灌注损伤模型、ECPR猪模型和心跳骤停小鼠模型。这是我们的 最终目标是将这些发现转化为紧急复苏护理，以挽救生命并最大限度地减少长期... 心脏骤停后出现长期神经功能障碍。一项全面的培训计划将培养校长 在赞助商的指导下，调查员作为内科科学家的技能(Terry L.Vanden Hoek，医学博士， 伊利诺伊大学芝加哥分校)和共同赞助商(约翰·霍普金斯大学医学硕士亨利·R·哈尔佩林)。

PROJECT SUMMARY/ABSTRACT Out-of-hospital cardiac arrest is a significant public health burden, affecting over 350,000 people annually in the United States. Survival remains less than 12% and long-term neurological deficit is common in survivors. Currently no drugs exist to reverse myocardial stunning or improve long-term survival with good neurological outcome, which highlights an urgent and unmet need in resuscitation. Pharmacological stimulation of cardiac glucose oxidation represents a potential key strategy for enhancing recovery and reversing a pathological increase in fatty acid oxidation which occurs after ischemia, although agents such as dichloroacetate are limited by toxicity. A novel cell-penetrating peptide, TAT-PHLPP9c, was developed which rapidly gains access to tissues and selectively inhibits PHLPP1, thereby enhancing activation of Akt. In a mouse model of cardiac arrest, intravenous administration of TAT-PHLPP9c during CPR improves recovery of cerebral blood flow and enhances activation of both Akt and pyruvate dehydrogenase in the heart and brain. In swine, administration of TAT- PHLPP9c during mechanical CPR significantly improves 24-hour survival. Agents such as TAT-PHLPP9c that quickly gain access to tissues to improve survival would represent a significant advancement in resuscitation. Targeting metabolic dysfunction with TAT-PHLPP9c may decrease the circuit flow rate needed for successful eCPR, which will allow for narrow cannulas to be used and may lead to wider availability of eCPR. Using high resolution magnetic resonance methods, this project will investigate the mechanisms underlying TAT-PHLPP9c cardioprotection and neuroprotection. The following hypotheses will be tested: 1) TAT-PHLPP9c directly targets the heart and enhances functional recovery from ischemia; 2) TAT-PHLPP9c decreases fatty acid oxidation in the post-ischemic heart; 3) TAT-PHLPP9c treatment during low flow eCPR improves cardiac arrest survival, neurological recovery, cerebral blood flow, and cerebral metabolism; 4) TAT-PHLPP9c reduces the circuit flow rate required for successful eCPR; and 5) TAT-PHLPP9c-mediated Akt activation in peripheral blood leukocytes reflects Akt activation in tissues from vital organs. These hypotheses will be tested using a Langendorff model of rat heart ischemia/reperfusion injury, a swine model of eCPR, and a mouse model of cardiac arrest. It is our ultimate goal to translate these findings to emergency resuscitative care in order to save lives and minimize long- term neurological disability after cardiac arrest. A comprehensive training plan will develop the principal investigator’s skills as a physician-scientist under the guidance of the sponsor (Terry L. Vanden Hoek, MD, University of Illinois at Chicago) and co-sponsor (Henry R. Halperin, MD, MA, Johns Hopkins University).