The Stress Response Kinase JNK and Alcohol Evoked Atrial Fibrillation

应激反应激酶 JNK 和酒精诱发心房颤动

• 批准号: 9333600
• 负责人: Xun Ai
• 金额: $ 53.78万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-15 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9333600
• 关键词: Ablation; Adult; Aging; Alcohol abuse; Alcohol consumption; Alcohol-Induced Disorders; Alcoholism; Alcohols; Animals; Arrhythmia; Atrial Fibrillation; Attenuated; Biochemical; Biological Assay; Blood alcohol level measurement; Calmodulin; Cardiac; Cardiac Electrophysiologic Techniques; Cardiovascular Diseases; Cell Death; Centers for Disease Control and Prevention (U.S.); Clinical; Clinical Data; Consumption; Development; Dominant-Negative Mutation; Economic Burden; Electrophysiology (science); Failure; Frequencies; Functional disorder; Gap Junctions; Heart; Heart Atrium; Heart failure; Human; Image; Inflammation; Injury; Institutes; Intervention; JUN gene; Knock-out; Knockout Mice; Knowledge; Link; Logic; MAPK8 gene; MAPK9 gene; Measurement; Mediating; Modification; Molecular; Molecular Biology; Mus; Muscle Cells; Mutant Strains Mice; N-terminal; Obesity; Optics; Organ; Outcome; Pathway interactions; Patients; Pattern; Peptides; Pharmacology; Phosphorylation; Phosphotransferases; Predisposition; Prevalence; Prevention; Procedures; Quality of life; Recurrence; Reporting; Research; Resistance; Risk; Risk Factors; RyR2; Ryanodine Receptor Calcium Release Channel; Sarcoplasmic Reticulum; Signal Transduction; Site; Societies; Stimulus; Stress; Tacrolimus Binding Proteins; Techniques; Testing; Therapeutic; Therapeutic Intervention; Time; Tissues; Transgenic Mice; Transgenic Organisms; Translating; Wild Type Mouse; aged; alcohol abstinence; alcohol abuser; alcohol exposure; base; binge drinking; biological adaptation to stress; calmodulin-dependent protein kinase II; carvedilol; clinical Diagnosis; clinical application; clinical practice; clinically significant; disorder prevention; drinking; high risk; human tissue; in vivo; inhibitor/antagonist; insight; mouse model; novel; novel therapeutic intervention; overexpression; oxidation; patient population; prevent; validation studies; voltage

Excessive binge alcohol intake (large amount of drinking within a short period of time) has been widely recognized as a high risk factor for atrial fibrillation (AF), which is the most common arrhythmia in diagnosed clinical practice. Although significant efforts have been made to date to reduce binge drinking, repeated binge remains prevalent nationwide and consequently the prevalence of alcohol associated AF is high. This causes a tremendous economic burden on our society due to expensive AF ablation procedures and high rate of recurrent AF after ablation if patients have coexisting cardiovascular diseases. Unfortunately, currently available pharmacological therapies for alcohol-provoked AF genesis remain ineffective due to a lack of understanding of its underlying mechanisms. Our proposed studies would fill this important knowledge gap by identifying stress-response c-Jun N-terminal kinase (JNK) as an important regulator in alcohol-provoked AF genesis. JNK is known to contribute to alcohol associated cell death and tissue injury. We have recently reported for the first time that activated JNK is critical in AF substrate formation and AF development. This JNK-AF relationship provides a logical pathway through which alcohol may increase propensity for AF. Indeed, our preliminary human and animal results indicate that excessive binge alcohol exposure dramatically increases JNK activation, which enhances calmodulin type II kinase (CaMKII, a well-known pro-arrhythmia molecule) dependent sarcoplasmic reticulum (SR) Ca leak and aberrant diastolic Ca sparks/waves, thus increasing propensity for atrial arrhythmias. Inactivated JNK transgenic mice with dominant negative mutations attenuated these alcohol-provoked abnormal Ca activities. In this proposal, the JNK contribution on RyR channel dysfunction and abnormal Ca activities will be dissected using unique mouse models with genetically manipulated JNK or CaMKII activities or RyR2 single channel function. To potentially translate results from mouse models to humans, we will perform validation studies in human donor hearts. We will use complementary electrophysiological approaches (voltage/Ca dual channel optical mapping and confocal Ca imaging in intact atria/isolated atrial myocytes as well as in vivo AF induction) and biochemical techniques to gain a comprehensive picture of the relationship between alcohol-activated JNK and Ca-triggered AF via increased RyR2-mediated SR Ca leak (Aim1). The mechanistic basis of how alcohol-evoked JNK alters RyR2 channel function to increase SR leak and sparks/waves (Aim 2) will be detailed at the levels of permeabilized atrial myocytes and single RyR2 channels in mice with clinical applicability verified using human donor heart tissue. This proposal integrates important functional measurements and fundamental mechanistic studies along with appropriate alternative approaches. Pharmacological interventions that limit JNK activity and modify RyR2 channel function will be tested as potential therapeutic options to prevent and/or treat AF. JNK’s RyR2 action may also add to arrhythmia risk tied to other stresses (e.g. aging, obesity, heart failure, etc.). Thus, the underlying mechanism defined and therapeutic interventions tested here may extend the potential significance beyond alcohol associated AF.

过量饮酒（短时间内大量饮酒）已被广泛 被认为是心房颤动（AF）的高危因素，心房颤动是临床诊断中最常见的心律失常 实践。尽管迄今为止已做出巨大努力来减少酗酒，但反复酗酒现象仍然存在 全国范围内普遍存在，因此与酒精相关的房颤的患病率很高。这造成了巨大的 由于昂贵的房颤消融手术和消融后房颤复发率高，给我们的社会带来了经济负担 如果患者同时患有心血管疾病。不幸的是，目前可用的药物疗法 由于缺乏对其潜在机制的了解，酒精引起的房颤发生仍然无效。我们的 拟议的研究将通过识别应激反应 c-Jun N 末端激酶来填补这一重要的知识空白 (JNK) 作为酒精引起的房颤发生的重要调节因子。众所周知，JNK 会导致与酒精相关的 细胞死亡和组织损伤。我们最近首次报道激活的 JNK 在 AF 底物中至关重要 形成和 AF 发展。这种 JNK-AF 关系提供了一条逻辑途径，酒精可以通过该途径 增加 AF 的倾向。事实上，我们的初步人类和动物研究结果表明，过量饮酒 暴露显着增加 JNK 激活，从而增强 II 型钙调蛋白激酶（CaMKII，一种众所周知的 促心律失常分子）依赖性肌浆网（SR）Ca 泄漏和异常舒张期 Ca 火花/波， 从而增加房性心律失常的倾向。具有显性失活突变的灭活JNK转基因小鼠 减弱了这些由酒精引起的异常钙活性。在这个提案中，JNK 在 RyR 通道上的贡献 将使用独特的基因操纵小鼠模型来剖析功能障碍和异常的 Ca 活性 JNK 或 CaMKII 活性或 RyR2 单通道功能。可能将小鼠模型的结果转化为 人类，我们将在人类捐赠心脏中进行验证研究。我们将使用补充电生理学 方法（完整心房/离体心房肌细胞的电压/Ca 双通道光学测绘和共焦 Ca 成像 以及体内 AF 诱导）和生化技术，以全面了解这种关系 通过增加 RyR2 介导的 SR Ca 渗漏，酒精激活的 JNK 和 Ca 触发的 AF 之间存在差异（Aim1）。这 酒精诱发的 JNK 如何改变 RyR2 通道功能以增加 SR 泄漏和火花/波的机制基础 （目标 2）将详细介绍具有临床症状的小鼠的透化心房肌细胞和单 RyR2 通道的水平 使用人类供体心脏组织验证了适用性。该提案整合了重要的功能测量 和基本机制研究以及适当的替代方法。药理干预 限制 JNK 活性和修改 RyR2 通道功能的药物将作为潜在的治疗选择进行测试，以预防 和/或治疗 AF。 JNK 的 RyR2 作用还可能增加与其他压力（例如衰老、肥胖、心脏疾病）相关的心律失常风险。 失败等）。因此，这里定义的潜在机制和测试的治疗干预措施可能会延长 除了酒精相关的房颤之外，还有潜在的意义。