The Role of the Dopamine Transporter in Psychostimulant Abuse

多巴胺转运蛋白在精神兴奋剂滥用中的作用

• 批准号: 10402705
• 负责人: AURELIO GALLI
• 金额: $ 6.11万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-01 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10402705
• 关键词: Amphetamine Abuse; Amphetamines; Anaerobic Bacteria; Animal Model; Attention Deficit Disorder; Behavior; Brain; Butyrates; Cessation of life; Chemosensitization; Data; Dopamine; Drosophila genus; Drosophila melanogaster; Fusobacterium nucleatum; Gnotobiotic; Growth; HDAC1 gene; Histone Deacetylase; Histone Deacetylase Inhibitor; Laboratories; Mediating; Medical; Messenger RNA; Modeling; Molecular; Motor Activity; Neurons; Oral Administration; Outcome; Pathogenesis; Pharmaceutical Preparations; Play; Property; Role; Substance Use Disorder; Testing; Translating; Volatile Fatty Acids; behavioral phenotyping; behavioral response; dopamine transporter; dysbiosis; experimental study; extracellular; fly; gastrointestinal; gut microbiome; gut-brain axis; in vivo; microbial; neuropsychiatric disorder; psychostimulant; stimulant abuse; substance use

Abstract Amphetamines (AMPHs) are psychostimulants commonly used for the treatment of neuropsychiatric disorders (e.g. attention deficit disorders). They are also abused with devastating outcomes. The abuse potential of AMPHs has been associated to their ability to cause mobilization of cytoplasmic dopamine (DA), which leads to an increase in extracellular DA levels. This increase is mediated by the reversal of the DA transporter (DAT) function that causes non-vesicular DA release, here defined as DA efflux. Notably, inhibition of DA efflux reduces both the ability of AMPH to increase motor activity as well as AMPH preference3, 6, 9. It has been suggested that imbalance in the gut microbiome (dysbiosis) participates in the pathogenesis of substance use disorders11. Consistent with this idea, psychostimulant abuse promotes dysbiosis12-15. Therefore, it is possible that changes in the gut microbiome and its metabolites may not only be a consequence of substance use disorders, but may play a role in mediating behavioral responses to drugs of abuse11. Microbial products such as short-chain fatty acids (SCFAs) are suspected to play a fundamental role in the gut-brain axis. Among SCFAs, butyrate is known to cross the BBB and directly act on neurons and glial cells16. Fusobacterium nucleatum (F. nucleatum) is an anaerobic filamentous gram-negative bacterial species that secretes butyrate17, growth of which is stimulated by AMPH abuse13-15. Our preliminary data demonstrate that in gnotobiotic Drosophila, colonization of the gastrointestinal track with F. nucleatum enhances AMPH-induced DA effluxes (recorded in isolated fly brains), as well as AMPH associated behaviors. This potentiation of AMPH actions by F. nucleatum was paralleled by oral administration of the SCFA butyrate. These data point to a powerful role of both F. nucleatum and butyrate in the psychomotor properties of AMPH. To understand, mechanistically, how F. nucleatum promotes AMPH actions, it is important to consider that changes in DAT expression regulate both AMPH-induced DA efflux and AMPH psychomotor actions19. Also, butyrate is a potent inhibitor of histone deacetylases (HDACs)20-22 and inhibition of HDACs, specifically HDAC1, robustly increases expression of both DAT mRNA and proteins21, 22. Our hypothesis is that F. nucleatum enhances AMPH actions by elevating DAT expression. This is mediated by secretion of butyrate and HDAC inhibition. We will test this hypothesis through the following specific aims: S.A. #1. To determine how F. nucleatum supports AMPH-induced DA efflux. These experiments will be performed in isolated brains of Drosophila melanogaster, an animal model our laboratory developed to study AMPH actions in vivo. Using this model, we will be able to translate the molecular discoveries of S.A. #1 to specific AMPH behavioral phenotypes. Thus, S.A. #2 focuses on behavior: S.A. #2. To determine the effect of F. nucleatum on AMPH-induced behaviors.

抽象的 苯丙胺（AMPHS）是通常用于治疗神经精神病的精神刺激药 疾病（例如注意力缺陷障碍）。他们还因毁灭性的结果而受到虐待。虐待潜力 AMPHS与引起细胞质多巴胺（DA）动员的能力有关 增加细胞外DA水平。这种增加是由DA转运蛋白（DAT）的逆转介导的 引起非挥发性DA释放的功能，此处被定义为DA外排。值得注意的是，抑制DA外排还原 AMPH提高运动活动的能力以及AMPH偏好3、6、9。 有人提出，肠道微生物组（营养不良）中的失衡参与 物质使用障碍11。与这个想法一致，精神刺激滥用会促进营养不良12-15。所以， 肠道微生物组及其代谢产物的变化可能不仅是物质的结果 使用疾病，但可能在调解对滥用药物的行为反应中发挥作用。11。 微生物产物（例如短链脂肪酸（SCFA））怀疑在 肠脑轴。在SCFA中，已知丁酸酯可以越过BBB并直接作用于神经元和神经胶质细胞16。 核细菌核（F. nucleatum）是一种厌氧丝状革兰氏阴性细菌，是该物种 分泌的丁酸17，其增长受到Amph滥用的刺激13-15。 我们的初步数据表明，在gnotobiotic果蝇中，胃肠道轨迹的定殖 使用F. nutleatum增强了Amph诱导的DA外排（以孤立的苍蝇大脑记录）以及Amph 相关行为。口服给予F. nuteatum对Amph作用的增强 scfa丁酸酯。这些数据表明，F. nucleatum和Butyrate在心理运动中的强大作用 Amph的特性。从机械上理解F. nutleatum如何促进Amph的作用，这很重要 考虑到DAT表达的变化调节Amph诱导的DA外排和Amph Psychomotor 动作19。同样，丁酸酯是组蛋白脱乙酰基酶（HDACS）的有效抑制剂，抑制HDACS，HDACS， 特别是HDAC1，可稳健地增加DAT mRNA和蛋白质的表达21，22。 我们的假设是F. nutleatum通过升高DAT表达来增强AMPH的作用。这是介导的 通过分泌丁酸酯和HDAC抑制作用。我们将通过以下特定目的检验这一假设： S.A.＃1。确定F. nucleatum如何支持Amph诱导的DA外排。 这些实验将在果蝇的孤立大脑中进行，这是一种动物模型，我们 实验室开发了在体内研究AMPH行动的发展。使用此模型，我们将能够翻译分子 S.A.＃1的发现对特定的AMPH行为表型。因此，S.A.＃2专注于行为： S.A.＃2。确定F.核对Amph诱导的行为的影响。