CaMKII signaling in physiology, heart failure and arrhythmias

摘要 心力衰竭和心律失常同时发生，以活性氧簇(ROS)增加为标志，以及 是尚未解决的重大公共卫生问题。尽管如此，ROS可能是有益的。然而，清晰的分子 缺乏支持ROS益处的机制。ROS的潜力被称为“好的和坏的” Ros悖论。这一杰出调查者奖的申请将提出创新的方法 从病理性ROS中理解和解剖健康的ROS这项研究计划的目标是测试一个 颠覆性概念认为ROS通过激活多功能钙和钙调蛋白激酶II(CaMKII) 同工异构体和细胞器选择通路决定ROS的生理和病理结果 发信号。我们发现氧化激活了CaMKII(ox-CaMKII，Erickson Cell 2008)，并建立了 OX-CaMKII是心脏中主要的CaMKII亚型，可导致心力衰竭和心律失常。我们最新的研究 扩展这些发现以表明OX-CaMKII也与哮喘有关。与之形成鲜明对比的是，我们的新产品 初步数据表明，OX-CaMKII，一种富含于骨骼肌的亚型，有益于并增强 耐力、胰岛素敏感性、瘦肉型、前列腺素C-1和脑源性神经营养因子的表达 脑源性神经营养因子(BDNF)，一种提高运动能力和防止心肌损伤的肌肉因子。我们的团队 发现CaMKII存在于线粒体中，线粒体靶向抑制CaMKII可以保护 对抗与高ROS相关的常见形式的心肌损伤(Joiner自然，2012)。在这里，我们建议 探索果蝇线粒体CaMKII全局性(即全身)抑制的新模式 黑腹鼠)和为拟议的OIA研究开发的小鼠。线粒体CaMKII抑制的果蝇有一种 延长寿命和对百草枯引起的氧化损伤的抵抗力，而整体抑制CaMKII 降低了脓毒症的死亡率，增加了体重。我们进行了新的磷酸蛋白质组学研究 代谢分析确定了线粒体CaMKII在代谢中起核心作用的意外靶标 和ROS的制作。我们的初步计算模型和实验数据表明 线粒体CaMKII的生理激活有助于有益的代谢战斗或逃逸反应 这会增加ATP；然而，持续和过度的线粒体CaMKII活性会导致扩张 由于复合体1丢失和ATP缺乏所致的心肌病。我们和我们的合作者将使用 艺术计算机建模、成像和新陈代谢研究，并生成一组老鼠和果蝇模型 使用CRISPR/Cas9分析CaMKII对心力衰竭、心律失常相关特定靶点的作用 为健康干杯。这项研究计划需要R35或类似的机制，因为它具有高度的创新性 挑战当前CaMKII和ROS生物学范式的概念，需要管理大量的 数据和生成新的动物模型，以及对较长时间框架的要求。

Abstract Heart failure and arrhythmias occur together, are marked by increased reactive oxygen species (ROS), and are major, unsolved public health problems. Despite this, ROS can be beneficial. However, clear molecular mechanisms supporting the benefits of ROS are lacking. The potential for ROS to be ‘good and bad’ is called the ROS paradox. This Outstanding Investigator Award application will propose innovative approaches to understanding and dissecting healthy from pathological ROS. The goal of this research program is to test a disruptive concept that ROS activation of the multifunctional calcium and calmodulin kinase II (CaMKII) by isoform and organelle selective pathways determine physiological and pathological outcomes of ROS signaling. We discovered that oxidation activates CaMKII (ox-CaMKII, Erickson Cell 2008) and established that ox-CaMKII, the major CaMKII isoform in heart, causes heart failure and arrhythmias. Our newest studies extended these findings to show that ox-CaMKII also contributes to asthma. In sharp contrast, our new preliminary data indicate that ox-CaMKII, an isoform enriched in skeletal muscle, is beneficial and enhances endurance, insulin sensitivity, lean phenotype, PGC-1, and expression or brain derived neurotrophic factor (BDNF), a myokine that improves exercise capacity and protects against myocardial injury. Our group discovered that CaMKII is present in mitochondria and that mitochondrial-targeted inhibition of CaMKII protects against common forms of myocardial injury associated with high ROS (Joiner Nature 2012). Here we propose to pursue new models of global (i.e. body-wide) mitochondrial CaMKII inhibition in flies (Drosophila melanogaster) and mice developed for the proposed OIA studies. Mitochondrial CaMKII inhibited flies have a prolonged lifespan and resistance to paraquat induced oxidant injury, while mice with global CaMKII inhibition have reduced mortality in sepsis and increased weight gain. We performed new phosphoproteomic and metabolic analyses that identified unanticipated mitochondrial CaMKII targets with central roles in metabolism and ROS production. Our preliminary computational modeling and experimental data suggest that physiological activation of mitochondrial CaMKII contributes to a beneficial metabolic fight or flight response that increases ATP; however, sustained and excessive mitochondrial CaMKII activity causes dilated cardiomyopathy due to loss of complex 1 and ATP deficiency. We and our collaborators will use state of the art computer modeling, imaging and metabolic studies, and generate a panel of mouse and Drosophila models using CRISPR/Cas9 to dissect contributions of CaMKII to specific targets relevant to heart failure, arrhythmias and to health. This research program requires an R35, or similar, mechanism because of its highly innovative concept that challenges current paradigms in CaMKII and ROS biology, the need to manage large amounts of data and generate new animals models, and the requirement for a prolonged timeframe.