A novel role for Oligodendrocyte Progenitor Cells (OPC) in opiate addiction

项目摘要/摘要 海洛因成瘾是一种慢性脑部疾病，其特征是强迫性吸食毒品，尽管 消极后果的存在。海洛因成瘾者终生容易复发，部分原因是 寻求毒品的动力增强了。不幸的是，海洛因成瘾的药物治疗仍然有限。 很大程度上是无效的。为了确定新的治疗靶点以帮助预防复发， 必须更好地了解导致复发的行为的分子机制，特别是动机。它是 已知滥用药物可诱导中脑边缘多巴胺系统关键区域的可塑性，包括 前额叶皮质(PFC)具体地说，该区域内的变化与适应不良有关 与上瘾相关的行为，包括对药物增强剂的动机，这可以使用 在成瘾的人体条件和动物模型中进行累进比率试验。虽然许多细胞 海洛因诱导的适应主要集中在前额叶内的神经细胞上，我们的初步研究 发表在《目标1》杂志上的数据发现，神经胶质细胞，特别是少突胶质细胞中存在一种失调现象。 继海洛因自我给药之后，一种上瘾的动物模型。我已经证明了一个转录因子密钥 在少突胶质细胞前体细胞(OPC)分化的调节中，SOX10在PFC中上调 在通过染色质改变剂BRG1自我给药后。此外，我已经将Sox10确定为 关键调停者的行为标志与成瘾、寻求毒品的动机有关。而这些 新奇的研究增加了我们对神经胶质转录本在成瘾状态中的作用的理解，这些变化 具体发生在祖细胞群体中，而不是整个谱系的细胞，目前仍不清楚。 因此，我建议研究OPC的一个特定亚型-NG2+细胞的细胞变化，这种细胞具有 不同于其他神经胶质细胞的生理特性。我在《目标2》中的中心假设是海洛因能诱导 与生理盐水对照组相比，PFC中NG2+细胞内转录水平的变化。我会决定 结合使用小鼠遗传模型，这一细胞亚群中基因转录的细胞类型特异性变化 病毒介导的基因转移利用翻译核糖体亲和力选择性地从NG2细胞中纯化RNA 净化(陷阱)。将使用RNA测序来分析RNA的转录本变化。从科学上讲， 这项提议将为NG2细胞在海洛因成瘾状态中发挥关键作用。虽然这些研究是 正在进行中，我将参加一个多方面的培训计划，旨在发展必要的非替补技能 为了达到我的最终目标，成为一名学术环境中的终身教员。此外，目标3是 旨在帮助确定一位资金充足的博士后导师，他继续帮助我开发 从博士后学者过渡到密集研究领域的独立研究员所需的技能 机构，这将包括接受我自己的资金通过K99奖。

Project Summary / Abstract Heroin addiction is a chronic brain disease that is characterized by compulsive drug intake despite the presence of negative consequences. Heroin addictions have a lifelong vulnerability to relapse, in part due to heightened motivation to seek the drug. Unfortunately, pharmacotherapies for heroin addiction remain limited and largely ineffective. In order to identify novel therapeutic targets to aid in the prevention of relapse, the molecular mechanism of behaviors leading to relapse, specifically motivation, must be better understood. It is known that drugs of abuse induce plasticity in key regions of the mesolimbic dopamine system, including the prefrontal cortex (PFC). Specifically, alterations within this region have been associated with the maladaptive behaviors associated with addiction, including motivation for drug reinforcers, which can be assed using a progressive ratio test in both the human condition and animal models of addiction. While many of the cellular adaptions induced by heroin have predominately focused on the neuronal cells within the PFC, our preliminary data, presented in Aim 1, has identified a dysregulation in glial cells, and specifically oligodendrocytes, following heroin self-administration, an animal model of addiction. I have shown that a transcription factor key in the regulation of oligodendrocyte progenitor cell (OPC) differentiation, Sox10, is upregulated in the PFC following heroin self-administration via chromatin remodeler BRG1. Furthermore, I have identified Sox10 as a critical mediator in a hallmark behavior associated with addiction, motivation to seek the drug. While these novel studies have added to our understanding of the role of glial transcripts in the addicted state, the changes that are occurring specifically in progenitor population, versus cells of the whole lineage, remain unknown. Therefore, I am proposing to examine cellular changes in a specific subtype of OPCs, NG2+ cells, which have distinct physiology properties from other glial cells. My central hypothesis in Aim 2 is that heroin induces transcriptomic changes within the NG2+ cells in the PFC compared to saline controls. I will determine the cell-type specific alterations in genes transcription in this subset of cells using genetic mouse models combined with viral-mediated gene transfer to selectively purify RNA from NG2 cells using Translating Ribosomal Affinity Purification (TRAP). The RNA will be analyzed for transcript changes using RNA-sequencing. Scientifically, this proposal will establish a critical role for NG2 cells in the heroin-addicted state. While these studies are underway, I will participate in a multifaceted Training Plan designed to develop the non-bench skills necessary to reach my ultimate goals of becoming a tenured faculty in an academic setting. In addition, Aim 3 was designed to aid in the identification of a well-funded postdoctoral mentor who continue to help me develop the skills necessary to transition from a postdoctoral scholar to an independent researcher at a research intensive institution, which will include receiving my own funding through a K99 award.