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.

过多的狂饮摄入量（短时间内大量饮酒）已广泛 被公认为心房颤动（AF）的高危险因素，这是诊断临床中最常见的心律失常 练习。尽管迄今为止已经为减少暴饮暴食而做出了重大努力，但仍在重复的暴饮暴食仍然 全国范围内普遍存在，因此与酒精相关的AF的流行率很高。这导致了巨大的 由于昂贵的AF消融程序和消融后的AF复发率高，因此我们社会上的经济伯恩尼 如果患者共存心血管疾病。不幸的是，目前可用于的药物疗法 由于缺乏对其潜在机制的了解，因此发行的酒精AFENES仍无效。我们的 提出的研究将通过识别应力响应C-JUN N末端激酶来填补这一重要的知识差距 （JNK）作为饮酒的AF Genesis中的重要调节剂。 JNK已知有助于酒精相关 细胞死亡和组织损伤。我们最近首次报道了激活的JNK在AF底物中至关重要 形成和自动房屋发展。这种JNK-AF关系提供了一种逻辑途径 增加AF的倾向。实际上，我们的初步人类和动物结果表明超级暴饮暴食 暴露急剧增加了JNK激活，从而增强了钙调蛋白II型激酶（CAMKII，众所周知 亲心律失常分子）依赖性肌质网（SR）Ca泄漏和异常的舒张期CA火花/波动， 因此增加了心律不齐的倾向。灭活的JNK转基因小鼠具有显性阴性​​突变 这些饮酒异常的CA活性减弱了。在此提案中，JNK在RYR频道上的贡献 功能障碍和异常CA活性将使用具有遗传操纵的独特小鼠模型进行解剖 JNK或CAMKII活动或RYR2单通道功能。可能将鼠标模型的结果转化为 人类，我们将在人类捐助者心中进行验证研究。我们将使用完整的电生理学 方法（电压/Ca双通道光学映射和完整心房/隔离心肌细胞中的共聚焦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泄漏，在酒精激活的JNK和CA触发的AF之间（AIM1）。这 酒精引起的JNK如何改变RYR2通道功能以增加SR泄漏和火花/波浪的机械基础 （AIM 2）将在具有临床的小鼠中详细介绍透化心肌细胞和单个RYR2通道的水平 使用人类供体心脏组织验证了适用性。该建议集成了重要的功能测量 以及基本的机械研究以及适当的替代方法。药理干预措施 限制JNK活动和修改RYR2通道功能将被测试为潜在的治疗选择，以防止 和/或治疗AF。 JNK的RYR2动作也可能增加与其他压力相关的心律不齐的风险（例如衰老，肥胖，心脏 失败等）。这，这里定义的基本机制和此处测试的热干预措施可能会扩展 与酒精相关的AF之外的潜在意义。