Cytokine Signaling as a Mediator of Fear and Anxiety After Myocardial Infarction

描述（由申请人提供）：我的长期目标是建立一个独立的研究项目，研究正常记忆和情绪处理的改变如何导致精神疾病的发展，以及导致从正常到病理转变的机制。到目前为止，我主要利用我的行为和分子神经科学训练来研究恐惧记忆的分子机制以及外部环境压力源在这些过程中的调节作用。内部事件，包括严重的疾病和心脏病发作，也经常导致焦虑、抑郁和创伤后应激障碍的增加，然而，这些内部事件后调节失调的机制尚不清楚。为了有效地研究焦虑和恐惧的内在诱因，我需要额外的训练和支持。因此，我组建了一个顾问小组，成员包括我的导师，分子和行为神经科学和神经免疫学专家耶琳娜·拉杜洛维奇博士，以及免疫学和心血管疾病模型专家斯蒂芬·米勒博士和道格拉斯·洛索多博士。在这些顾问的指导下，我将接受免疫学技术和概念的培训，教授诱导心肌梗死的手术方法，在Radulovic博士的指导下，我将接受有关焦虑和恐惧动物模型的问题的指导，以及神经免疫学概念和其他分子技术的具体指导。本项目旨在研究特定脑区细胞因子信号在焦虑和过度恐惧产生中的作用。为了做到这一点，我将开发一个新的模型，将心脏病发作（心肌梗死，MI）的外科模型（触发全身细胞因子反应）与焦虑和恐惧的行为模型结合起来。我将使用免疫学和分子神经科学技术来确定雄性和雌性小鼠这些行为改变的信号关联和原因。在Aim 1中，我将确定心肌梗死后焦虑和夸大恐惧的出现。Aim 2将确定心肌梗死后大脑中与焦虑和恐惧相关区域细胞因子的失调。最后，Aim 3将研究介导焦虑和恐惧增加的细胞因子依赖的细胞内分子信号机制。在所有的实验中，我将同时研究雄性和雌性老鼠。我假设焦虑和增强的恐惧将是心肌梗死的后果，在心肌梗死后的几周和几个月里出现并持续下去。与这些行为变化同时，我预计大脑区域中介导焦虑和恐惧的促炎细胞因子会增加。最后，我假设细胞因子依赖的JAK/STAT信号介导心肌梗死后的情绪和记忆失调。这些发现将与心脏病发作后PTSD的具体病因以及慢性外部压力源后是否同样的机制介导PTSD的更普遍的问题高度相关。在这个项目的指导阶段，我将执行Aims 1和2，这将为实验数据提供坚实的基础，并获得技能和知识。在独立阶段，我将确定细胞因子介导的JAK/STAT信号在mi后焦虑障碍和PTSD出现中的激活和作用。这个项目将提供一个框架，以维持我正在进行的，独立的研究生涯。我希望根据该项目产生的数据，研究的两个主要方向将是：(1)心肌梗死后行为或信号改变中出现的性别差异的详细机制研究，以及(2)细胞因子信号在从急性适应性应激效应到慢性适应性不良综合征的转换中的作用。在这个项目的指导阶段，我的训练将在西北大学精神病学和行为科学系的Jelena Radulovic博士的实验室进行。在这里，我可以获得许多资源，包括合作讨论，进行实验所需的设备，研讨会和课程，以获得广泛和深入的培训，以及专业发展机会，包括研讨会和研究报告。此外，我将有机会获得我的顾问和咨询小组成员的资源和专业知识。Miller和Losordo，分别用于细胞因子分析和心肌梗死和组织学。通过这个项目获得的训练，我将学习免疫学、外科以及其他行为和分子神经科学技能，建立一个多学科模型，用于后续的研究项目，并为未来的研究方向提供数据基础。因此，在指导阶段结束时，我将拥有设计、执行和分析实验的技能和知识，这些实验将阐明内部和外部事件调节记忆和情绪处理的分子机制，从而导致精神疾病。

DESCRIPTION (provided by applicant): My long-term goal is to develop an independent program of research investigating how alterations of normal memory and emotional processing contributes to the development of psychiatric disorders, and the mechanisms that cause the switch from normal to pathological. To date, I have primarily used my behavioral and molecular neuroscience training to investigate the molecular mechanisms underlying fear memory and the role of external environmental stressors in the modulation of these processes. Internal events, including severe illness and heart attack, also frequently cause increased anxiety, depression and PTSD, however the mechanisms that mediate dysregulation after these internal events remain unknown. In order to effectively study internal triggers of anxiety and fear, I will require additional training and support. As such, I have assembled an advisory panel consisting of my mentor, Dr. Jelena Radulovic, an expert in molecular and behavioral neuroscience and neuroimmunology, as well as experts in immunology and models of cardiovascular disease, Dr. Stephen Miller and Dr. Douglas Losordo respectively. With these consultants, I will obtain training on immunological techniques and concepts, be taught the surgical methods for induction of myocardial infarction, and, under the mentorship of Dr. Radulovic, I will receive guidance on issues related to animal models of anxiety and fear, as well as specific tutelage on concepts in neuroimmunology and additional molecular techniques. This project aims to investigate the contribution of cytokine signaling in specific brain regions to the emergence of anxiety and excessive fear. To do this I will develop a new model, integrating a surgical model of heart attack (myocardial infarction, MI) that triggers a systemic cytokine response, with behavioral models of anxiety and fear. I will use immunological and molecular neuroscience techniques to determine the signaling correlates and causes of these behavioral alterations in male and female mice. In Aim 1, I will determine the emergence of anxiety and exaggerated fear after MI. Aim 2 will determine post-MI dysregulation of cytokines in brain regions related to anxiety and fear. Finally, Aim 3 will examine the cytokine-dependent intracellular molecular signaling mechanisms that mediates increased anxiety and fear. In all experiments I will concurrently study male and female mice. I hypothesize that anxiety and enhanced fear will be a consequence of MI, emerging and persisting in the weeks and months after MI. In parallel to these behavioral changes, I expect increased pro-inflammatory cytokines in brain regions mediating anxiety and fear. Finally, I hypothesize that cytokine-dependent JAK/STAT signaling mediates emotional and mnemonic dysregulation after MI. These findings will be highly relevant both for the specific etiology of post-heart attack PTSD, and for the more general question of whether the same mechanisms mediate PTSD after chronic external stressors. During the mentored phase of this project, I will execute Aims 1 and 2, which will provide a solid basis in both experimental data, and acquired skills and knowledge, for the independent phase in which I will determine the activation and role of cytokine-mediated JAK/STAT signaling the post-MI emergence of anxiety disorders and PTSD. This project will provide a framework to sustain ongoing research in my ongoing, independent research career. I expect that two main directions for research following data generated by this project will be (1) detailed mechanistic studies of sex differences emerging in behavioral or signaling alterations after MI, and (2) the role of cytokine-signaling in the switch from acute, adaptive effects of stress, to chronic, maladaptive syndromes. My training during the mentored phase of this project will be conducted in the laboratory of Dr. Jelena Radulovic in the department of Psychiatry and Behavioral Sciences at Northwestern University. Here, I have access to many resources including collaborative discussions, the equipment required to conduct the experiment, seminars and classes for the breadth and depth of training, and professional development opportunities, including workshops and research presentations. In addition, I will have access to the resources and expertise of my consultants and advisory panelists, Drs. Miller and Losordo, for cytokine analysis and myocardial infarction and histology, respectively. Through the training gained through this project I will learn immunological, surgical, and additional behavioral and molecular neuroscience skills, develop a multidisciplinary model to use in subsequent research projects, and generate data on which to base future research directions. As such, by the end of the mentored phase, I will have the skills and knowledge to design, execute, and analyze experiments that will elucidate the molecular mechanisms by which internal and external events modulate memory and emotional processing, and thereby contribute to psychiatric disorders. PUBLIC HEALTH RELEVANCE: This project, based on the clinical observations that a large proportion of heart attack patients subsequently develop anxiety or post-traumatic stress disorder, aims to utilize animal models of anxiety and fear to investigate the post-heart attack mechanism triggering these psychiatric disorders. I expect that inflammatory signaling in the brain will play a major role in the development of anxiety and fear after heart attack, and that these pathways will be novel targets for treatment and prevention of anxiety and post-traumatic stress disorder.