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

描述(由申请人提供)：我的长期目标是开发一个独立的研究计划，调查正常记忆和情绪处理的变化如何有助于精神障碍的发展，以及导致从正常到病理转换的机制。到目前为止，我主要使用我的行为和分子神经科学培训来研究恐惧记忆背后的分子机制，以及外部环境应激源在这些过程中的调节作用。内部事件，包括严重疾病和心脏病发作，也经常导致焦虑、抑郁和创伤后应激障碍，但这些内部事件后调节失调的机制仍不清楚。为了有效地研究焦虑和恐惧的内在诱因，我需要额外的培训和支持。因此，我组建了一个顾问小组，成员包括我的导师耶琳娜·拉杜洛维奇博士，分子和行为神经科学和神经免疫学专家，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，我将获得免疫学技术和概念的培训，学习诱发心肌梗死的外科方法，并在拉杜洛维奇博士的指导下，接受与焦虑和恐惧的动物模型有关的问题的指导，以及神经免疫学概念和其他分子技术的具体指导。该项目旨在研究特定大脑区域的细胞因子信号在焦虑和过度恐惧的出现中的作用。为了做到这一点，我将开发一个新的模型，将引发全身细胞因子反应的心脏病发作(心肌梗塞)的外科模型与焦虑和恐惧的行为模型相结合。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变化的信号相关性和原因。在目标1中，我将确定MI后焦虑和夸大恐惧的出现。目标2将确定心肌梗死后与焦虑和恐惧相关的脑区细胞因子的失调。最后，目标3将研究细胞因子依赖的细胞内分子信号机制，这些机制介导了焦虑和恐惧的增加。在所有的实验中，我将同时研究雄性和雌性小鼠。我假设，焦虑和加剧的恐惧将是心肌梗塞的结果，在心肌梗塞后的几周和几个月里出现并持续。在这些行为变化的同时，我预计大脑中调节焦虑和恐惧的区域中的促炎细胞因子会增加。最后，我假设依赖细胞因子的JAK/STAT信号调节心梗后的情绪和记忆失调。这些发现将与心脏病发作后创伤后应激障碍的特定病因以及更普遍的问题高度相关，即是否相同的机制在慢性外部应激后调节创伤后应激障碍。在这个项目的指导阶段，我将执行目标1和目标2，这将为独立阶段的实验数据以及获得的技能和知识提供坚实的基础，在这个独立阶段，我将确定细胞因子介导的JAK/STAT的激活和作用，信号传递MI后焦虑障碍和创伤后应激障碍的出现。这个项目将提供一个框架，以支持我正在进行的独立研究生涯中的正在进行的研究。我预计，在这个项目产生的数据之后，研究的两个主要方向将是(1)关于MI后行为或信号变化中出现的性别差异的详细机制研究，以及(2)细胞因子信号在从压力的急性适应效应转换到慢性适应不良综合征中的作用。在这个项目的指导阶段，我的培训将在西北大学精神病学和行为科学系的耶琳娜·拉杜洛维奇博士的实验室进行。在这里，我可以获得许多资源，包括协作讨论、进行实验所需的设备、针对培训广度和深度的研讨会和课程，以及专业发展机会，包括研讨会和研究报告。此外，我将获得我的顾问和顾问小组成员米勒博士和洛索多博士的资源和专业知识，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培训，我将学习免疫学、外科以及其他行为和分子神经科学技能，开发一个多学科模型用于后续研究项目，并生成数据作为未来研究方向的基础。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，从而促进精神障碍。 公共卫生相关性：该项目基于临床观察，即很大比例的心脏病发作患者随后会发展成焦虑或创伤后应激障碍，旨在利用焦虑和恐惧的动物模型来研究心脏病发作后引发这些精神障碍的机制。我预计，大脑中的炎症信号将在心脏病发作后焦虑和恐惧的发展过程中发挥重要作用，这些途径将成为治疗和预防焦虑和创伤后应激障碍的新靶点。

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.