Cell type transcriptional mechanisms of polysubstance choice

项目总结 在这个直接响应RFA-DA-23-015的新R01应用程序中，我们的研究团队建议研究 芬太尼和甲基苯丙胺多药对细胞类型特异性分子机制的调控 在药物使用轨迹的启动和退出阶段。我们建议克服当前的 利用男性药物与食物选择程序的临床前分析进行多物质研究的局限性 和雌性大鼠，更全面地捕捉到人类使用多物质的严重程度，通过模拟 兼用成瘾药物与替代药物的行为错配与决策 非药物增强剂。我们将把这些增强的行为模型与单核RNA测序相结合 内侧前额叶皮质(PFC)和伏核(NAC)的(SnRNAseq)，这两个关键脑区涉及 在药物强化和药物摄取中，捕捉和表征确切的药物诱导分子 发生在特定细胞类型中的适应，包括非神经细胞。我们将直接检验这一假设 芬太尼和甲基苯丙胺联合使用的协同作用导致药物使用增加 与芬太尼或芬太尼不同的行为和脑分子适应 单独使用甲基苯丙胺；这种多物质的协同作用涉及到独特的转录适应 大脑区域，积累作为药物经验的函数，并导致行为分配错误 倾向于使用毒品，而不是更有益的奖励活动，这是吸毒成瘾的标志。我们将测试 这一最重要的假设有两个目的。在目标1中，我们将揭示芬太尼/甲基苯丙胺的影响 多物质使用期间的停药阶段的物质使用轨迹。我们将使用药物对食物自助式 盐水、单独芬太尼、单独甲基苯丙胺的给药选择程序 芬太尼/甲基苯丙胺组合揭示多物质使用的长期历史如何协同作用 在经历戒断时增加躯体戒断效应和吸毒行为。到时候我们会的 在PFC和NAC中执行SnRNAseq以询问脑细胞类型特定的转录适应 这些老鼠。在目标2中，我们将类似地执行药物与食物选择程序和这些大脑的SnRNAseq 探索在药物使用开始时出现行为和转录适应的区域 经验。我们将继续比较来自AIMS 1和2的SnRNAseq数据，以了解 芬太尼/甲基苯丙胺多物质细胞类型转录谱随药物使用的变化 弹道。该项目将揭示芬太尼和甲基苯丙胺是如何协同产生适应不良药物的。 药物使用不同阶段的选择行为和脑细胞类型特异性转录反应 这些都是复苏的常见障碍。从这个项目中获得的结果将为发现 治疗核心决策过程的新的和更有效的药物是独一无二的 被多种物质的使用所扰乱。

PROJECT SUMMARY In this new R01 application that is directly responsive to RFA-DA-23-015, our research team proposes to study the cell type specific molecular mechanisms regulated by fentanyl and methamphetamine polysubstance use at both the initiation and withdrawal stages of the substance use trajectory. We propose to overcome current limitations in polysubstance research by utilizing preclinical assays of drug-vs.-food choice procedures in male and female rats, which more fully capture the severity of polysubstance use seen in humans by modeling the behavioral misallocation and decision making between concurrently available addictive drugs and alternative non-drug reinforcers. We will combine these enhanced behavioral models with single nuclei RNA sequencing (snRNAseq) of the medial prefrontal cortex (PFC) and nucleus accumbens (NAc), key brain regions implicated in drug reinforcement and drug-taking, to capture and characterize the exact drug-induced molecular adaptations that occur in specific cell types, including non-neuronal cells. We will directly test the hypothesis that the synergistic action of combined fentanyl and methamphetamine use produces enhanced drug use behaviors and brain molecular adaptations that are distinct from what is achieved by either fentanyl or methamphetamine use alone; that this polysubstance synergy involves unique transcriptional adaptations by brain region, accumulates as a function of drug experience, and contributes to the behavioral misallocation towards drug use over more beneficial rewarding activities that is the hallmark of drug addiction. We will test this overarching hypothesis in two Aims. In Aim 1, we will uncover the impact of fentanyl/methamphetamine polysubstance use during the withdrawal phase of the substance use trajectory. We will use drug-vs.-food self- administration choice procedures for saline, fentanyl alone, methamphetamine alone, and fentanyl/methamphetamine combinations to uncover how an extended history of polysubstance use synergizes to increase somatic withdrawal effects and drug taking behavior while experiencing withdrawal. We will then perform snRNAseq in the PFC and NAc to interrogate the brain cell type specific transcriptional adaptations in these rats. In Aim 2, we will similarly perform drug-vs.-food choice procedures and snRNAseq of these brain regions to explore the emergence of behavioral and transcriptional adaptations at the of initiation of drug use experience. We will go on to compare our snRNAseq data from Aims 1 and 2 to understand how the fentanyl/methamphetamine polysubstance cell type transcriptional profile changes over the substance use trajectory. This project will reveal how fentanyl and methamphetamine synergize to produce maladaptive drug choice behaviors and brain cell type specific transcriptional responses at distinct stages of the substance use trajectory that are common barriers to recovery. Results gained from this project will inform the discovery of novel and more efficacious pharmacological agents to treat the core decision making process that is uniquely disrupted by polysubstance use.