COCA: Project 1. Drug-induced ROS and Epigenetic Mechanisms

项目概要-项目1科万 治疗药物成瘾的一个主要挑战是对药物成瘾的分子机制缺乏了解， 药物使用会使大脑功能产生持续的变化，即使在长时间的药物使用后， 禁欲慢性药物使用涉及一个表观遗传过程，涉及染色质重塑酶， 组蛋白去乙酰化酶5（HDAC 5），位于纹状体中型多棘神经元中，其功能是限制 多种成瘾相关行为，包括可卡因和海洛因寻求的恢复。然而，在这方面， HDAC 5在服用药物期间和之后的调节和功能是复杂的，并且知之甚少。可卡因和 海洛因产生改变细胞氧化还原状态的活性氧和氮物质（ROS/RNS）， 氧化还原介导的半胱氨酸巯基修饰改变靶蛋白的结构/功能，包括IIa类 HDAC。用抗氧化剂和谷胱甘肽前体N- 乙酰半胱氨酸（NAC），减少可卡因和海洛因寻求恢复的脆弱性， 阻止ROS促进的HDAC 5核出口。项目1的长期目标是了解氧化还原 HDAC 5和NAC调节海洛因和可卡因复吸的蛋白质信号传导和表观遗传机制 行为，希望找到更好的治疗策略来治疗药物成瘾。我们 假设：（1）可卡因和海洛因产生的氧化应激修饰HDAC 5半胱氨酸巯基， - 促核素，其促进核输出并降低HDAC 5的抗复发作用，以及 (2)重复NAC治疗的抗复发作用至少部分是由于其保护HDAC 5的能力， 从ROS信号事件，促进核排斥和基因表达的变化。我们将使用 尖端的小鼠遗传学和cre依赖性病毒工具，允许时间限定和细胞类型特异性 在药物服用和复发事件期间操纵延髓核核心神经元。 目标1。分子和细胞机制：在这一目标，我们将确定如何可卡因和海洛因SA 调节HDAC 5的氧化还原敏感性翻译后修饰、亚细胞分布、基因组结合和 基因表达的调控。 目标2.电路特异性：在这一目标中，我们将采取尖端的分子遗传学方法来解剖 HDAC 5负调节可卡因和海洛因药物寻求的细胞类型特异性作用。 目标3。治疗：在这个目标中，我们将分析NAC对HDAC 5的调节，并测试HDAC 5的作用。 在NAC的持久能力，以减少恢复海洛因和可卡因寻求。

PROJECT SUMMARY – Project 1 Cowan A major challenge for treating drug addiction is the poor understanding of the molecular mechanisms by which drug use produces persistent changes in brain function that facilitate drug seeking even after long periods of abstinence. Chronic drug use engages an epigenetic process, involving the chromatin-remodeling enzyme, histone deacetylase 5 (HDAC5), in striatal medium spiny neurons that functions to limit the development of multiple addiction-related behaviors, including reinstatement of cocaine and heroin seeking. However, HDAC5’s regulation and function during and after drug taking is complex and poorly understood. Cocaine and heroin produce reactive oxygen and nitrogen species (ROS/RNS) that alter the redox state of the cell, and redox-mediated cysteine thiol modifications alter the structure/function of target proteins, including class IIa HDACs. Repeated treatment of animals or humans with the antioxidant and glutathione precursor, N- acetylcysteine (NAC), reduces the vulnerability to reinstatement of cocaine and heroin seeking, and NAC blocks ROS-promoted HDAC5 nuclear export. The long-term goal of Project 1 is to understand the redox protein signaling and epigenetic mechanisms by which HDAC5 and NAC regulate heroin and cocaine relapse behaviors in hopes of identifying better therapeutic strategies for the treatment of drug addiction. We hypothesize that: (1) cocaine- and heroin-produced oxidative stress modifies HDAC5 cysteine thiol groups in the nucleus accumbens, which promotes nuclear export and reduces the anti-relapse actions of HDAC5, and (2) the anti-relapse effects of repeated NAC treatment are due, at least in part, to its ability to protect HDAC5 from ROS signaling events that promote nuclear exclusion and changes in gene expression. We will use cutting-edge mouse genetics and cre-dependent viral tools that allow for time-delimited and cell-type specific manipulation of nucleus accumbens core neurons during drug taking and relapse events. Aim 1. Molecular and Cellular Mechanisms: In this aim, we will determine how cocaine and heroin SA regulate HDAC5’s redox-sensitive posttranslational modifications, subcellular distribution, genomic binding and regulation of gene expression. Aim 2. Circuit Specificity: In this aim, we will take a cutting-edge molecular genetic approach to dissect the cell-type specific roles for HDAC5 to negatively-regulate cocaine and heroin drug seeking. Aim 3. Treatment: In this aim, we will analyze the regulation of HDAC5 by NAC, and test the role of HDAC5 in the long-lasting ability of NAC to reduce reinstatement of heroin and cocaine seeking.