The Role of Fyn Kinase in the Dorsal Striatum in Heroin Use Disorder

项目概要/摘要： 阿片类药物使用障碍是美国的一场公共卫生危机，在美国大约有80，000例过量用药。 2021.成瘾可以分为三个阶段：狂欢/中毒，戒断/负面影响， 专注/渴望。目前对阿片类药物使用障碍的治疗替代了奖励并防止戒断， 但是对于与成瘾的第三阶段相关的习惯性/强迫性使用存在治疗差距， 因此需要更好地理解这种行为的分子和细胞基础。使用 无偏筛选人类海洛因使用者背侧纹状体死后样本的表观基因组， 赫德实验室确定了编码Fyn激酶的基因的启动子区域作为具有最大变异的基因座。 这可以用神经元中的海洛因来解释。Fyn mRNA表达在这些人类样本中和在这些人中均升高。 接受海洛因自我给药的大鼠的背侧纹状体。对菲恩的抑制， 分子药物或siRNA输注到背侧纹状体降低了海洛因的反应， 复发的模式。背侧纹状体的不同亚区介导不同方面的寻药 行为我发现，强迫性寻找海洛因的老鼠在两个组织中的Fyn表达都有所增加， 背内侧和背外侧纹状体，而非强迫性服用海洛因的大鼠显示Fyn增加 表达于背内侧亚区。我的项目将调查的分子和细胞机制， 海洛因自我给药行为中的Fyn。我会在背内侧和背外侧纹状体 次区域和测试动机和强迫海洛因寻求行为，与假设， 在背内侧纹状体中敲低Fyn将减少目标导向反应，而在背外侧纹状体中敲低Fyn将减少目标导向反应。 纹状体会减少习惯性反应。我将在这些子区域进行RNA测序， Fyn调制的分子网络。为了确定Fyn如何调节海洛因寻求过程中的神经活动，我 将使用体内纤维光度法记录背侧纹状体中的神经元活动。这些实验将使 我来揭示Fyn在海洛因使用障碍中的作用的分子和细胞机制， 对有动机和习惯性吸毒行为模型的影响。我将学习一种行为模式， 强迫症，钙成像和RNA测序，这将使我能够回答有关 从分子变化到神经元活动再到行为，在我未来作为一名物理学家和科学家的职业生涯中。

Project Summary/Abstract: Opioid use disorder is a public health crisis in the United States with roughly 80,000 overdoses taking place in 2021. Addiction can be conceptualized in three phases: binge/intoxication, withdrawal/negative affect, and preoccupation/craving. Current treatments for opioid use disorder substitute reward and prevent withdrawal, but there exists a treatment gap for the habitual/compulsive use associated with the third phase of addiction, necessitating better understanding of the molecular and cellular underpinnings of this behavior. Using an unbiased screening of the epigenome of postmortem samples of dorsal striatum from human heroin users, the Hurd Lab identified a promoter region for the gene encoding Fyn kinase as the locus with the most variance explained by heroin use in neurons. Fyn mRNA expression was elevated both in these human samples and in the dorsal striatum of rats that underwent heroin self-administration. Inhibition of Fyn either with a small molecule drug or siRNA infusions into the dorsal striatum decreased response for heroin in a translational model of relapse. Different subregions of the dorsal striatum mediate different aspects of drug-seeking behavior. I found that rats that compulsively sought heroin showed increased Fyn expression in both dorsomedial and dorsolateral striatum, while rats that took heroin non-compulsively showed increased Fyn expression in the dorsomedial subregion. My project will investigate the molecular and cellular mechanisms of Fyn in heroin self-administration behavior. I will knock down Fyn in dorsomedial and dorsolateral striatal subregions and test motivated and compulsive heroin seeking behavior, with the hypothesis that Fyn knockdown in dorsomedial striatum will reduce goal-directed responding, while Fyn knockdown in dorsolateral striatum will reduce habitual responding. I will perform RNA-sequencing in these subregions to assess molecular networks modulated by Fyn. To determine how Fyn regulates neural activity during heroin seeking, I will record neuronal activity in the dorsal striatum using in-vivo fiber-photometry. These experiments will enable me to uncover the molecular and cellular mechanisms underlying Fyn’s role in heroin use disorder and its effects on behavioral models of motivated versus habitual drug taking. I will learn a behavioral model of compulsivity, calcium imaging, and RNA-sequencing which will equip me to answer questions relating molecular changes to neuronal activity to behavior in my future career as a physician-scientist.