Heart-platelet crosstalk: JNK, AF, and thrombogenesis

心脏-血小板串扰：JNK、AF 和血栓形成

• 批准号: 10112302
• 负责人: Xun Ai
• 金额: $ 60.68万
• 依托单位: RUSH UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-05-15 至 2021-08-01
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10112302
• 关键词: Abnormal Platelet; Age; Aging; Agonist; Alcohol abuse; Alcohols; Animal Model; Animals; Antibodies; Arrhythmia; Atrial Fibrillation; Biochemical; Blood; Blood Platelets; Blood coagulation; Cardiac; Cardiac Electrophysiologic Techniques; Cardiovascular Diseases; Clinical; Clinical Data; Coupling; Data; Development; Electrophysiology (science); Endocytosis; Event; Experimental Designs; Foundations; Gene Transfer; Gene Transfer Techniques; Genetic; Goals; Heart; Heart Atrium; Heart failure; Hemorrhage; Homeostasis; Human; ITPR1 gene; Image; Intervention; Knock-out; Knowledge; Lead; Link; MAPK8 gene; MAPK9 gene; Maintenance; Measurement; Mechanics; Mediating; Messenger RNA; Modeling; Molecular; Molecular Biology; Morbidity - disease rate; Mus; Myocardial Infarction; N-terminal; Optics; Organ Donor; Oryctolagus cuniculus; Outcome; Pathogenicity; Patients; Phospholipase C; Phosphotransferases; Physiology; Platelet Activation; Platelet aggregation; Predisposition; Prevalence; Process; Proteins; Reporting; Rest; Risk; Risk Factors; Role; Signal Pathway; Signal Transduction; Sinus; Specific qualifier value; Stress; Stress Response Signaling; Stroke; Techniques; Testing; Therapeutic; Therapeutic Intervention; Thromboembolism; Thrombophilia; Thrombosis; Thrombus; Time; Translating; aged; alcohol exposure; base; biological adaptation to stress; calmodulin-dependent protein kinase II; clinically significant; design; heart cell; high risk; human tissue; in vivo; in vivo imaging; inhibitor/antagonist; mortality; mouse model; novel; novel therapeutics; platelet function; prevent; stroke risk; targeted treatment; thrombogenesis; voltage

Atrial fibrillation is the most common arrhythmia with a high risk of stroke and stroke-associated mortality and morbidity. The prevalence of AF and stroke, increases markedly with age and alcohol abuse. The classic pathophysiological concept is atrial mechanical stasis during AF promotes thromboembolism formation. Thus, antithrombotic therapy has been a key component of AF management. However, due to the stroke-bleeding dilemma, and the varying risk of thromboemobolic events, only about half of all AF patients receive antithrombotic therapies. Emerging clinical findings are challenging our long-standing AF-stroke dogma, leaveing the causal link between AF and thrombogenesis even more baffling. The goal of this proposal is to fill this knowledge gap, establish a previously unrecognized crosstalk between heart and platelets through circulating microparticles containing heart-origin activated stress molecule JNK2 and reveal the underlying mechanism of the dual functional role of cardiac JNK2 in both thrombogenesis and AF development. Our intriguing preliminary findings suggest that age- and alcohol-driven JNK activation in the heart is mechanistically linked to the platelet activation and thus increased thrombogenesis. This is potentially a paradigm-shifting concept. Next, we found heart cells shed JNK-microparticles (JNK-MPs) and these MPs could then interact with platelets through an action of JNK2-specific endocytosis. Consequently, increased platelet JNK2 could lead to abnormal platelet Ca homeostasis and increase resting platelet reactivity. All these intriguing preliminary results and our previous findings point to a previously unrecognized JNK2-signaling crosstalk between the heart and platelets. In this proposal, we will use complementary electrophysiological approaches (dual voltage/Ca optical mapping, intravital confocal platelet Ca imaging, in vivo atrial painting gene transfer, ex vivo platelet aggregation, in vivo thrombus formation, and single IP3R channel recording) and biochemical techniques in intact atria, platelets, and even in single channels to gain a comprehensive picture of the relationship between cardiac JNK2, thrombogenesis and AF risk. The JNK2 actions on AF propensity, platelet Ca handling, and resting platelet reactivity will be dissected using several novel cardiac specific inducible Tg mouse models with manipulated JNK2 (JNK1) activity (activated or inactivated) and aged animals with and without atrial-specific JNK2 inhibition using a unique in vivo atrial painting gene transfer technique. To potentially translate the results from animal models to humans, we will perform selective studies in viable human platelets and hearts from organ donors. Our specific aims are: 1) Define the link between cardiac JNK2 (cJNK2) activation, platelet function, thrombogenesis and AF and 2) Delineate how the heart talks to platelets through circulating JNK2-MPs, governing platelet Ca handling and hyper-reactivity. This proposal integrates important functional measurements and fundamental mechanistic studies along with appropriate alternative approaches. Cardiac specific interventions (in vivo atrial gene transfer & genetic JNK inhibition) that limit cardiac JNK2 activity will be tested as proof-in-principle studies and explored as potential therapeutic options to prevent and/or treat thrombogenesis and AF.

心房颤动是最常见的心律不齐，中风和中风相关的死亡率和发病率的高风险。 AF和中风的患病率随着年龄和酗酒而明显增加。经典的病理生理学 概念是AF期间的心房机械暂停会促进血栓栓塞形成。因此，抗血栓疗法 一直是AF管理的关键组成部分。但是，由于流血困境以及风险的变化 在血栓形成的事件中，只有大约一半的AF患者接受抗血栓形成疗法。新兴临床 调查结果挑战了我们长期存在的AF-Stroke教条，使AF和AF之间的因果关系 血栓形成甚至更令人困惑。该建议的目的是填补这一知识差距，建立以前的 通过循环的微粒，含有心脏根源 激活的应力分子JNK2并揭示心脏JNK2双重功能作用的潜在机制 血栓形成和AF发育。我们有趣的初步发现表明年龄和酒精驱动 心脏中的JNK激活与血小板激活相关，从而增加了血栓形成。这 可能是一个范式转移概念。接下来，我们发现心脏细胞脱落JNK-Microparticles（JNK-MP），这些 然后，MP可以通过JNK2特异性内吞作用的作用与血小板相互作用。因此，增加了 血小板JNK2可能导致异常的血小板Ca稳态并增加静息骨骼反应性。所有这些 有趣的初步结果，我们以前的发现指出了先前未知的JNK2信号串扰 在心脏和血小板之间。在此提案中，我们将使用互补的电生理方法（双重 电压/Ca光学映射，插入式共聚焦血小板Ca成像，体内心房绘画基因转移，离体血小板 完整的聚集，体内血栓形成和单个IP3R通道记录）和生化技术 心房，血小板，甚至在单个渠道中，以全面了解心脏之间的关系 JNK2，血栓形成和AF风险。 JNK2对AF倾向，血小板CA处理和休息血小板的作用 将使用具有操纵JNK2的几种新颖的心脏特异性诱导TG小鼠模型来解剖反应性 （JNK1）活性（激活或灭活）和具有和不使用心房特异性JNK2抑制的老年动物使用A 独特的体内心房绘画基因转移技术。可能将结果从动物模型转化为 人类，我们将对可行的人血小板和器官捐献者的心脏进行选择性研究。我们的具体目标 是：1）定义心脏JNK2（CJNK2）激活，血小板功能，血栓形成和AF和2之间的联系 描述通过循环的JNK2-MP，管理血小板CA的处理和 过度反应性。该建议整合了重要的功能测量和基本机械研究 以及适当的替代方法。心脏特异性干预措施（体内心房基因转移和遗传 限制心脏JNK2活性的JNK抑制作用将被测试为原则研究，并探讨了潜在的 预防和/或治疗血栓形成和AF的治疗选择。