Enhancing Cardiac Protection

描述（由申请人提供）： 心肌缺血/再灌注损伤仍然是世界范围内发病率和死亡率的主要原因。在20世纪80年代发现的缺血预处理揭示了一种有效的内源性保护机制的存在，以增加心脏中的缺血耐受性，其可以通过在长期缺血/再灌注事件之前的短暂缺血和再灌注期产生。在缺血组织再灌注之前诱发的缺血后处理为心脏保护提供了临床相关的靶点。许多内源性配体和药物，包括挥发性麻醉剂，在心脏中产生预处理和后处理，提供心脏保护免受心肌缺血/再灌注损伤。尽管在过去的30年中对心脏保护机制有了重要的见解，但在临床环境中利用预处理和后处理的全部潜力仍未实现。临床环境中的心脏保护策略受到几个因素的限制，包括年龄和与衰老相关的疾病。我们以前已经表明，参与心脏保护的信号分子需要在小窝内发挥作用，并与小窝蛋白相互作用，以产生有效的心脏保护。我们提出测试新的假设，即小窝蛋白的丢失和小窝微结构域内精确的心脏保护信号的破坏导致老年动物中明显的挥发性麻醉剂诱导的心脏保护受损，并且小窝蛋白的重新表达可以恢复挥发性麻醉剂诱导的心脏保护信号，该信号已经被老化所损害。该基金的目的是：1：确定年轻和老年心肌细胞中挥发性麻醉剂和caveolin在肌膜上相互作用的机制，2：确定年轻和老年心肌细胞中挥发性麻醉剂诱导的心脏保护信号分子、caveolin和线粒体相互作用的机制，3：确定Cav-3的过表达是否恢复了老年小鼠和人类心脏中挥发性麻醉剂诱导的心脏保护作用。我们将使用最先进的分子生物学技术，电子顺磁共振技术，成像技术和生理技术在心肌细胞，人类心肌和临床相关模型的I/R损伤的机制，并产生重要的临床前数据，以支持使用caveolins作为新的治疗老年退伍军人患者的心肌缺血/再灌注损伤的风险。

DESCRIPTION (provided by applicant): Myocardial ischemia/reperfusion injury remains a major cause of morbidity and mortality worldwide. The discovery of ischemic preconditioning in the 1980's revealed the presence of a potent endogenous protective mechanism to increase ischemic tolerance in the heart that could be produced by brief periods of ischemia and reperfusion preceding a prolonged ischemia/reperfusion event. Ischemic postconditioning, evoked prior to reperfusion of ischemic tissue, has provided a clinically relevant target for cardiac protection. Numerous endogenous ligands and pharmaceuticals, includeing volatile anesthetics, produce pre and post conditioning in the heart, providing cardiac protection from myocardial ischemia/reperfusion injury. Despite significant insights gained over the last 30 years into mechanisms of cardiac protection, the full potential of harnessing pre and post conditioning in the clinical setting remains unfulfilled. Cardiac protection strategies in the clinical setting are limited by several factors including age and diseases related to aging. We have shown previously that the signaling molecules involved in cardioprotection need to function within caveolae and interact with caveolins to produce effective cardioprotection. We propose to test the novel hypothesis that loss of caveolin and disruption of precise cardioprotective signaling within caveolar microdomains results in the impaired volatile anesthetic-induced cardiac protection evident in aged animals and that re- expression of caveolin can restore volatile anesthetic-induced cardiac protective signaling that has been impaired by aging. The aims of the grant will 1: Determine mechanisms involved the interaction of volatile anesthetics and caveolins at the sarcolemmal membrane in young and aged cardiac myocytes, 2: Determine the mechanisms involved in the interaction of volatile anesthetic-induced cardioprotective signaling molecules, caveolins and mitochondria in young and aged cardiac myocytes, and 3: Determine if overexpression of Cav-3 restores volatile anesthetic-induced cardiac protection in aged mice and human hearts. We will use state of the art molecular biology techniques, electron paramagnetic resonance technology, imaging technology, and physiological techniques in cardiac myocytes, human myocardium and clinically relevant models of I/R injury to focus on mechanism and produce important preclinical data to support the use of caveolins as novel therapeutics for aged veteran patients at risk of myocardial ischemia/reperfusion injury.