Investigating cytoskeletal dynamics in astrocyte structure and cocaine seeking behavior

研究星形胶质细胞结构和可卡因寻求行为的细胞骨架动力学

• 批准号: 10721883
• 负责人: Janay Franklin
• 金额: $ 3.96万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10721883
• 关键词: Abstinence; Actins; Acute; Affect; Area; Astrocytes; Automobile Driving; Behavior; Behavioral; Bioinformatics; Brain; Cessation of life; Chronic; Cocaine; Cocaine Abuse; Cocaine use disorder; Collaborations; Cytoskeletal Proteins; Cytoskeleton; Data; Data Analyses; Development; Down-Regulation; Elements; Extinction; FDA approved; Functional disorder; Gene Expression; Genes; Genetic; Heroin; Home; Immunohistochemistry; Impairment; Individual; Intervention; Investigation; Knowledge; Learning; Measures; Mediating; Messenger RNA; MicroRNAs; Microinjections; Microscopy; Molecular; Neuroglia; Neurons; Nucleus Accumbens; Pathway Analysis; Pharmaceutical Preparations; Phosphorylation; Property; Proteins; Public Health; Publishing; Rattus; Relapse; Reporting; Research; Resolution; RiboTag; Role; Saline; Scientist; Self Administration; Structure; Surface; Synapses; Synaptic Transmission; Synaptic plasticity; Testing; Training; United States; Validation; Viral; Withdrawal; candidate identification; cell type; cocaine exposure; cocaine relapse; cocaine seeking; cocaine self-administration; cocaine use; computerized tools; confocal imaging; differential expression; drug of abuse; effective therapy; experience; experimental study; ezrin; insight; long term abstinence; mRNA Expression; overdose death; pre-clinical; prolonged abstinence; psychostimulant; reward circuitry; skills; stimulant use disorder; symposium; synaptic function; synaptogenesis; therapeutic candidate; therapeutic target; tool; transcriptome; transcriptome sequencing; treatment group; treatment strategy; virus genetics

ABSTRACT Cocaine abuse presents a significant public health concern across the United States, as the number of cocaine-related deaths in the United States has almost tripled since 2013. Despite an urgent need for intervention, an FDA-approved treatment for Cocaine Use Disorder is lacking. Hence, there is a considerable need for investigations into the mechanisms that drive relapse vulnerability. Recent advances indicate that cocaine-induced structural adaptations in astrocytes may contribute to relapse vulnerability. Astrocytes are the most abundant glial cell in the brain and regulate varied critical functions, including synaptic transmission and plasticity. Research in the Reissner lab has revealed that astrocytes in the nucleus accumbens are significantly structurally impaired following cocaine self-administration and extinction. In addition, preliminary data from our lab indicate that rat long-access (LgA, 6h/day) self-administration followed by prolonged abstinence (45d) leads to a significant ~40% decrease in astrocyte volume, surface area, and synaptic colocalization. However, the mechanisms driving these observations are unknown. I hypothesize that downregulation of astrocyte cytoskeletal dynamics is a major contributor to these effects. Accordingly, this proposal will examine how astrocyte cytoskeletal dynamics are altered following chronic cocaine self-administration and prolonged abstinence, and how manipulation of cytoskeletal proteins can influence cocaine seeking. Of note, phosphorylation of ezrin, an actin-cytoskeleton linker protein that is abundantly and preferentially expressed in astrocytes, is downregulated by acute cocaine exposure. Thus, the overarching hypothesis of this proposal is that cocaine and abstinence-induced astrocyte structural deficits result from alterations in astrocyte cytoskeletal dynamics, which further contribute to cocaine-seeking behaviors that are exacerbated following long-term abstinence. To test this hypothesis, in Aim 1 I will measure the effects of cocaine self-administration and abstinence on cytoskeletal proteins, including ezrin, and I will use an astrocyte-specific AAV to manipulate ezrin expression, to examine its role astrocyte structure and further in cocaine-seeking behaviors. In Aim 2, I will use a RiboTag AAV, to isolate astrocyte-specific mRNAs in conjunction with RNAseq as an unbiased approach to measure cocaine and abstinence-induced changes in the astrocyte transcriptome that may contribute to cocaine-seeking behavior. I will specifically analyze results to measure relative expression profiles of cytoskeletal proteins among these astrocyte mRNAs. These results will provide a greater understanding of how dysfunctions in astrocyte structure actively contribute to cocaine abuse and relapse.

抽象的 可卡因滥用在美国提出了重要的公共卫生问题，因为 自2013年以来，美国与可卡因相关的死亡几乎几乎增加了两倍。尽管迫切需要 干预措施是对可卡因使用障碍的FDA批准的治疗方法。因此，有一个很大的 需要调查驱动复发脆弱性的机制。最近的进步表明 可卡因诱导的星形胶质细胞结构适应可能有助于复发脆弱性。星形胶质细胞是 大脑中大多数丰富的神经胶质细胞，并调节各种关键功能，包括突触传播和 可塑性。 Reissner Lab中的研究表明，伏隔核中的星形胶质细胞显着 可卡因自我给药和灭绝后，结构受损。此外，我们的初步数据 实验室表明，大鼠长期访问（LGA，6H/天）自我给药，然后延长节制（45d） 导致星形胶质细胞体积，表面积和突触共定位的显着降低约40％。然而， 推动这些观察结果的机制尚不清楚。我假设星形胶质细胞的下调 细胞骨架动力学是这些作用的主要因素。因此，该建议将研究如何 慢性可卡因自我给药后，星形胶质细胞细胞骨架动力学发生了变化 戒酒以及细胞骨架蛋白的操纵如何影响可卡因的寻求。值得注意的是， Ezrin的磷酸化是一种肌动蛋白 - 细胞骨架链接蛋白，在 星形胶质细胞被急性可卡因暴露而下调。因此，该提议的总体假设是 可卡因和禁欲引起的星形胶质细胞结构缺陷是由于星形胶质细胞的改变而导致的 细胞骨架动力学，进一步有助于可卡因的寻求可卡因行为，这些行为被加剧了 长期禁欲。为了检验这一假设，在目标1中，我将衡量可卡因自我管理的影响 对包括ezrin在内的细胞骨架蛋白的禁欲，我将使用星形胶质细胞特异性AAV来操纵 Ezrin的表达，以检查其星形胶质细胞结构的作用，并在寻求可卡因的行为中进一步研究。在AIM 2中，我 将使用Ribotag AAV，与RNASEQ结合使用星形胶质细胞特异性mRNA作为无偏见 测量可卡因和禁欲引起的星形胶质细胞转录组变化的方法 有助于寻求可卡因的行为。我将专门分析结果以测量相对表达曲线 这些星形胶质细胞mRNA中的细胞骨架蛋白。这些结果将提供对 星形胶质细胞结构的功能障碍如何积极促进可卡因滥用和复发。