Neuromolecular Drivers of Impulsivity in Addictive Disorders

描述（由申请人提供）：本提案要求支持一个全面的培训计划，该计划将使诺埃尔·c·阿纳斯塔西奥博士能够拓宽、增强和完善技术技能，这些技能是从事富有成效的独立研究事业所必需的。我的长期职业目标是在一个研究密集型学术机构获得终身教职，并建立一个研究项目，专注于最终的科学目标，了解冲动特质的精神药理学，以推进成瘾的预防和治疗。药物滥用的各个方面，包括开始吸毒、从偶然到强迫性吸毒的过渡、寻求药物行为的维持以及恢复寻求药物的倾向，都与高水平的内在冲动有关。中皮质边缘回路中5-羟色胺（5-HT） 2C受体（5-HT2CR）功能的失调与成瘾周期的这些阶段以及冲动表型的表现有关。有证据表明，5-羟色胺（5-HT）神经传递通过其同源5-HT2C受体（5-HT2CR）和谷氨酸神经传递通过嗜离子性谷氨酸n-甲基-d -天冬氨酸受体（NMDAR）在冲动和成瘾行为的认知和/或行为维度中发挥关键作用，特别是在mPFC中，该区域是决策和目标导向行为的一部分。因此，mPFC中5-羟色胺和谷氨酸系统之间的相互作用可能导致可卡因成瘾的认知障碍。在K99辅导阶段(1-2年；目标1-2)来自一个合作导师团队，包括分子技术（例如，蛋白质交联，细胞系的创建，生物反应试验）的培训，以分析受体亚细胞定位和信号转导调节，以及复杂的行为神经科学/药理学/分子遗传学技术（例如，免疫组织化学，颅内微输注，病毒介导的基因转移）。我还将在职业发展、资助、实验室人员和学生管理以及财务和规划责任方面获得指导，这些都是运营独立实验室的关键。在R00独立阶段（3-5年；目标3-4年）提出的研究计划建立在这一训练的基础上，更具体地关注mPFC NMDAR和5-HT2CR:NMDAR异质复合物作为固有冲动和可卡因相关复发事件表达的功能变阻器的神经生物学。核心假设是5-HT2CR和NMDAR功能的平衡驱动mPFC输出，而这种平衡的丧失会导致固有的冲动性，导致成瘾障碍和相关复发事件的脆弱性。我们将检验这一假设，并揭示导致固有冲动的神经分子驱动因素，以及与可卡因相关的复发事件（例如，线索反应）相关的可卡因诱发冲动。为了解决这一假设，我们制定了四个具体目标：目标1)确定mPFC 5-HT2CR在内在冲动性中的作用；目的2)确定mPFC 5-HT2CR在总体冲动性/线索反应性中的作用；目的3)阐明mPFC NMDAR在内在冲动性和总体冲动性/线索反应性中的作用；目的4)在体外和离体研究5-HT2CR: NMDAR复合物的生物学特性。我们将确定神经元5-HT2CR和NMDAR系统控制冲动性，重新平衡这些系统可能最终支持以冲动性为特征的障碍的行为恢复。总之，这些创新的转化研究将是第一个系统地探索5-HT2CR和nmdar介导的功能在成瘾相关表型中的贡献和相互作用，最终允许设计靶向药物治疗来促进戒断和预防成瘾疾病复发。

DESCRIPTION (provided by applicant): This proposal requests support for a comprehensive training plan that will enable Noelle C. Anastasio, Ph.D., to broaden, enhance, and refine technical skills that are necessary for a productive independent research career. My long-term career goal is to obtain a tenure-track faculty position at a research-intensive academic institution and build a research program focused upon the ultimate scientific goal to understand the psychopharmacology of the impulsivity trait to advance prevention and treatment of addiction. Various aspects of drug abuse, including the initiation of drug-taking, the transition from casual to compulsive drug use, the maintenance of drug-seeking behaviors as well as the penchant to reinstate drug-seeking correlate with high levels of inherent impulsivity. Dysregulation in serotonin (5-HT) 2C receptor (5-HT2CR) function within the mesocorticolimbic circuit has been implicated in these stages of the addiction cycle as well as the manifestation of the impulsive phenotype. There is evidence that both serotonin (5-HT) neurotransmission through its cognate 5-HT2C receptor (5-HT2CR) and glutamate neurotransmission through the ionotropic glutamate N-methyl-D-aspartate receptor (NMDAR) play key roles in the cognitive and/or behavioral dimensions of impulsivity and addictive behaviors, especially in the mPFC, a region integral to decision-making and goal-directed behavior. Thus, the interaction between 5-HT and glutamate systems in the mPFC may contribute to the cognitive impairments seen in cocaine addiction. I will receive multifaceted training during the K99 mentored phase (Years 1-2; Aims 1-2) from a team of collaborating mentors that includes training in molecular techniques (e.g., protein crosslinking, creation of cell lines, bioresponsive assays) to analyze receptor subcellular localization and signal transduction regulation, as well as sophisticated behavioral neuroscience/pharmacology/molecular genetics techniques (e.g., immunohistochemistry, intracranial microinfusion, viral-mediated gene transfer). I will also receive mentoring in career development, grantsmanship, laboratory staff and student management and fiscal and planning responsibilities critical to running an independent laboratory. The research plan that is proposed during the R00 independent phase (Years 3-5; Aims 3-4) builds on this training to focus more specifically on the neurobiology of the mPFC NMDAR and the 5-HT2CR:NMDAR heteromeric complex as functional rheostats in expression of inherent impulsivity and cocaine-associated relapse events. The central hypothesis is that a balance of 5-HT2CR and NMDAR function drives mPFC output and that the loss of this balance contributes to inherent impulsivity, leading to vulnerability for the development of addictive disorders and associated relapse events. We will test this hypothesis and uncover neuromolecular drivers responsible for inherent impulsivity as well as the cocaine- evoked impulsivity in relation to cocaine-associated relapse events (e.g., cue reactivity). To address this hypothesis, four specific aims have been formulated: Aim 1) establish the role for mPFC 5-HT2CR in inherent impulsivity; Aim 2) establish the role for mPFC 5-HT2CR in aggregate impulsivity/cue reactivity; Aim 3) elucidate the role for mPFC NMDAR in inherent impulsivity and aggregate impulsivity/cue reactivity; Aim 4) explore the biology of the 5-HT2CR: NMDAR complex in vitro and ex vivo. We will determine that neuronal 5-HT2CR and NMDAR systems govern impulsivity and that rebalancing these systems may ultimately support behavioral recovery in disorders marked by impulsivity. Together, these innovative translational studies will be the first to systemically explore the contribution and interaction of 5-HT2CR- and NMDAR-mediated function in addiction- relevant phenotypes, ultimately allowing for the design of targeted pharmacotherapeutics to promote abstinence and prevent relapse in addictive disorders.