Glial-mediated synaptic remodeling in drug addiction

胶质细胞介导的毒瘾突触重塑

• 批准号: 10363436
• 负责人: Yan Dong
• 金额: $ 56.61万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-01 至 2027-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10363436
• 关键词: AMPA Receptors; Address; Adult; Animal Model; Applications Grants; Astrocytes; Behavioral; Brain; Cocaine; Cocaine withdrawal; Cues; Drug Addiction; Electrophysiology (science); Ensure; Exhibits; Filopodia; Funding; Generations; Glutamates; Image; Lead; Measures; Mediating; Memory; Molecular; Monitor; Mus; Neurobiology; Neurons; Newborn Infant; Nucleus Accumbens; Outcome; Pharmaceutical Preparations; Play; Population; Prevention; Process; Property; Relapse; Retrieval; Rodent; Role; Signal Transduction; Slice; Synapses; Synaptic plasticity; Testing; Therapeutic; Thinness; Training; Up-Regulation; Vertebral column; Withdrawal; Work; addiction; base; cell type; cocaine exposure; cocaine self-administration; drug withdrawal; experience; experimental study; imaging study; in vivo; in vivo imaging; insight; memory retrieval; neural circuit; novel; recruit; response; success; synaptogenesis; targeted treatment; tool; transcriptome sequencing; two photon microscopy

Abstract This grant application proposes to understand the role of astrocytes in mediating cocaine-induced circuit alterations that drive cocaine seeking and relapse. Outcomes of the first funding period for this R01 project demonstrate that cocaine self-administration (SA) activates an astrocyte-mediated synaptogenic mechanism to generate AMPA receptor (AMPAR)-silent synapses in principal medium spiny neurons (MSNs) in nucleus accumbens shell (NAcSh). During withdrawal from cocaine SA, a subset of these cocaine-generated NAcSh synapses mature and strengthen by recruiting AMPARs. Experimentally converting and locking cocaine- generated NAcSh synapses within their silent state during drug withdrawal substantially decreases cue- induced cocaine seeking. By measuring intracellular Ca2+ activities, preliminary studies reveal that NAcSh astrocyte activities are upregulated by cocaine administration, and that this upregulation is increased after 5-d cocaine SA, indicating a ‘sensitization’ process in astrocytes. Furthermore, after cocaine SA, NAcSh astrocytes acquire the ability to respond to cocaine-associated cues by increasing their activities, and experimentally increasing astrocyte activities re-silences cocaine-generated NAcSh synapses. These and other preliminary results lead to the current hypothesis: NAcSh astrocytes gain unique properties through cocaine experience to regulate cocaine-generated synapses and formulate specific neuronal ensembles that drive cue-induced cocaine seeking after drug withdrawal. This hypothesis will be tested by three lines of experimentation. First, using astrocyte-specific molecular tools, proposed experiments will test the specific hypothesis that astrocytic levels of mGluR5 are upregulated by cocaine SA, which, in turn, mediates sensitized in vivo responses of NAcSh astrocytes to cocaine and cocaine-associated cues after cocaine withdrawal. In parallel, selective RNA- seq of NAc astrocytes will reveal novel molecular substrates for cocaine action in this cell type. Second, using in vivo two-photon microscopy combined with slice electrophysiology, proposed experiments will test the specific hypothesis that increased activities of NAcSh astrocytes is both sufficient and necessary for cue re- exposure-induced re-silencing of cocaine-generated NAcSh synapses, and thus can be used to reduce cue- induced cocaine seeking after drug withdrawal. Third, using GCaMP-mediated in vivo Ca2+ imaging, proposed experiments will test the specific hypothesis that the neuronal ensembles are formed, in part, by astrocyte- mediated synaptogenesis in response to cocaine, and then drive cue-induced cocaine seeking after drug withdrawal. These proposed experiments will characterize several novel astrocyte-associated substrates through which addiction-related memories can be manipulated for therapeutic benefits.

抽象的 该赠款申请提案，以了解星形胶质细胞在介导可卡因诱导的电路中的作用 推动可卡因寻求和继电器的改动。该R01项目的第一个资助期的成果 证明可卡因自我给药（SA）会激活星形胶质细胞介导的突触机制 在原子核中产生AMPA接收器（AMPAR） - 丝毫突触 伏伏壳（NACSH）。从可卡因SA撤离期间，这些可卡因生成的NACSH的一部分 突触成熟并通过招募AMPAR来加强。实验转换和锁定可卡因 - 在戒毒期间，在其沉默状态内产生的NACSH突触大大下降了提示 - 诱发可卡因寻求。通过测量细胞内Ca2+活性，初步研究表明NACSH 可卡因管理更新了星形胶质细胞活动，并且此更新在5-D之后增加 可卡因SA，表明星形胶质细胞中的“敏化过程”。此外，在可卡因SA之后，NACSH星形胶质细胞 通过增加活动，并在实验中获得对可卡因相关的提示做出反应的能力 不断增加的星形胶质细胞活性重新获得可卡因生成的NACSH突触。这些和其他初步 结果导致当前的假设：NACSH星形胶质细胞通过可卡因经验获得独特的特性 调节可卡因生成的突触，并制定特定的神经元集合，以驱动提示诱导的 吸毒后寻求可卡因。该假设将通过三行实验来检验。第一的， 使用星形胶质细胞特异性分子工具，提出的实验将检验星形胶质细胞的特定假设 MGLUR5的水平由可卡因SA更新，这又介导了体内敏感的体内反应 可卡因戒断后，NACSH星形胶质细胞与可卡因和可卡因相关线索。并行，选择性RNA- NAC星形胶质细胞的SEQ将揭示该细胞类型可卡因作用的新型分子底物。第二，使用 体内两光子显微镜结合了切片电生理学，提出的实验将测试 具体假设，即NACSH星形胶质细胞的活动增加既足够又足够 可卡因生成的NACSH突触的暴露引起的重新排列，因此可用于减少提示 诱导可卡因在戒毒后寻求可卡因。第三，使用GCAMP介导的体内Ca2+成像，提出 实验将测试特定的假设，即神经元集合是由星形胶质细胞形成的 响应可卡因的介导的突触发生，然后驱动提示诱导的可卡因寻求药物 提取。这些提出的实验将表征几个新型星形胶质细胞相关的底物 可以通过与成瘾相关的记忆来进行治疗益处。