Investigation On The Behavior And Related Neuro-Electrochemistry Of Potential Medications For The Treatment Of Substance Use Disorders.

对治疗物质使用障碍的潜在药物的行为和相关神经电化学的调查。

• 批准号: 10699661
• 负责人: Gianluigi Tanda
• 金额: $ 238.04万
• 依托单位: NATIONAL INSTITUTE ON DRUG ABUSE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10699661
• 关键词: Acute; Affinity; Alcohol abuse; Amphetamines; Attention Deficit Disorder; Autophagocytosis; Autoreceptors; Behavior; Behavioral; Behavioral Paradigm; Binding; Body Weight; Brain; Brain Diseases; Brain region; Carbenoxolone; Chemical Structure; Chemosensitization; Clinical; Clinical Research; Clinical Treatment; Clinical Trials; Cocaine; Cocaine Abuse; Cocaine Users; Cocaine use disorder; Collaborations; Computer Models; Corpus striatum structure; Coupling; Crack Cocaine; Data; Diet; Dopamine; Dopamine Receptor; Dose; Drug Design; Drug Prescriptions; Electrochemistry; Electrophysiology (science); Elements; Enzymes; Future; Gap Junctions; Genetic; Genetically Engineered Mouse; Goals; High Fat Diet; Human; Hydroxychloroquine; Impairment; In Vitro; Intravenous; Investigation; Knockout Mice; Measures; Mediating; Medical; Membrane; Metabolic Pathway; Methamphetamine; MicroRNAs; Microdialysis; Modafinil; Molecular; Molecular Conformation; Mus; Nerve; Neurobiology; Neurons; Neurotransmitters; Nucleus Accumbens; Obesity; Optics; Pathologic; Patients; Periodicity; Pharmaceutical Preparations; Pharmacology; Phenotype; Physiological; Play; Population; Pre-Clinical Model; Procedures; Process; Psychological reinforcement; Research; Research Project Grants; Rewards; Ritalin; Rodent; Role; Scanning; Self Administration; Series; Sleep Disorders; Sprague-Dawley Rats; Stimulant; Substance Use Disorder; Synapses; Synaptic Receptors; System; Testing; Therapeutic; Time; Up-Regulation; Wild Type Mouse; Zinc; abuse liability; analog; attenuation; base; cocaine self-administration; cocaine use; comorbidity; conditioned place preference; density; dietary; dopamine transporter; dopaminergic neuron; drug discrimination; drug of abuse; early onset; enantiomer; experimental study; extracellular; in vivo; inhibition of autophagy; inhibitor; insight; methamphetamine use; neural; neurochemistry; neurotransmission; novel; pre-clinical; preclinical study; predictive modeling; psychostimulant; receptor; regional difference; response; reuptake; stimulant abuse; stimulant use disorder; substance use treatment; virtual

The dopamine (DA) transporter (DAT) is the main pharmacologic target of abused psychostimulants like cocaine but also of prescribed medications like modafinil (MOD), which has shown little, if any, propensity for abuse in clinical or preclinical studies. Recently, we have explored the neurochemical and behavioral actions of MOD to better characterize its atypical psychostimulant profile. We found that MOD had a lower potency and efficacy than cocaine in stimulating nucleus accumbens shell (NAS) and core (NAC) DA levels, but, at variance with abused psychostimulants there were no statistically significant regional differences between accumbens subregions. In drug-discrimination studies MOD showed cocaine-like subjective effects at lower doses and earlier onset times than expected based on its DA effects. Those results suggest that non-DA-dependent actions may be playing a role in its unique pharmacological profile. In order to discover a potential non-dopaminergic mechanism for these MOD actions, we compared its behavioral and neurochemical effects with those of methylphenidate, another clinically approved medication that inhibits the neuronal reuptake of DA. We showed that methylphenidate, but not MOD, maintained intravenous self-administration in Sprague-Dawley rats similarly to cocaine. Both MOD and methylphenidate pretreatments potentiated cocaine self-administration. Cocaine, at self-administered doses, stimulated mesolimbic DA levels. This effect was potentiated by methylphenidate, but not by MOD pretreatments, indicating DA-dependent actions for methylphenidate, but not MOD. MOD is known to facilitate electrotonic neuronal coupling by actions on gap junctions. Carbenoxolone, a gap junction inhibitor, antagonized MOD, but not methylphenidate potentiation of cocaine self-administration. Our results indicate that MOD shares mechanisms with cocaine and methylphenidate but has a unique pharmacological profile that includes facilitation of electrotonic coupling and lower abuse liability, which may be exploited in future therapeutic drug design for cocaine use disorder. Though MOD might prove useful as a treatment for specific addicted populations (e.g. heavy crack-cocaine users, or cocaine and methamphetamine addicts without alcohol abuse comorbidity), broader effective medications for psychostimulant use disorders are still an unmet medical need. To this end, several newly synthesized analogs of MOD, for example JJC8-091 and JJC8-088, have been tested in our preclinical models as potential medications for methamphetamine (METH) and cocaine use disorder. JJC8-091 and JJC8-088, were assessed alone and in combination with cocaine to elucidate neurochemical correlates to their divergent behavioral profiles. Despite sharing significant structural similarity, JJC8-088 was more cocaine-like, increasing extracellular DA concentrations in the NAS efficaciously and more potently than JJC8-091. In contrast, JJC8-091 was not self-administered and was effective in blocking cocaine-induced reinstatement to drug seeking. Electrophysiology experiments confirmed that JJC8-091 was more effective than JJC8-088 at inhibiting cocaine-mediated enhancement of DA neurotransmission. Further, when VTA DA neurons in DAT-cre mice were optically stimulated, JJC8-088 produced a significant leftward shift in the stimulation-response curve, similar to cocaine, while JJC8-091 shifted the curve downward, suggesting attenuation of DA-mediated brain reward. Computational models predicted that while JJC8-088 prefers or stabilizes an outward facing conformation of DAT, like cocaine, JJC8-091 stabilizes DAT towards a more occluded conformation. Recently, we have collaborated on a project related to the potential effects of cocaine on neural autophagy in vitro and in vivo. Autophagy inhibitors, i.e. hydroxychloroquine and SBI-0206965, reduce the locomotor stimulant effect of systemic administration of cocaine and its related stimulation of extracellular NAS DA levels in mice. Cocaine-induced autophagy degrades transporters for DA but not serotonin in the NAS. Autophagy inhibition impairs cocaine conditioned place preference in mice. These findings indicate that autophagic degradation of DAT modulates behavioral and neurochemical actions of cocaine. Our research collaborations also include an investigation on the role of the microRNA system on neuronal signaling in mice lacking the translin/trax microRNA-degrading enzyme (Tsn KO mice). We found an altered behavioral and neurochemical response to psychostimulants, and also robust adiposity in the context of normal body weight, suggesting that this phenotype might reflect elevated brain levels of the psychostimulants tested. Analysis of the effect of diet-induced increases in adiposity in wild type mice on brain amphetamine levels also demonstrated that brain amphetamine levels correlate with adiposity. Increased adiposity displayed by Tsn KO mice or by wild type mice fed a high-fat diet correlates with elevated brain amphetamine levels. As amphetamine and its analogues are widely used to treat attention deficit disorder, which is associated with obesity, further studies are warranted to assess the impact of adiposity on amphetamine levels in these patients. In a more recent collaboration, we investigated the role of Zinc in cocaine seeking and abuse vulnerability. Cocaine increases synaptic dopamine (DA) by blocking the DA transporter (DAT). This process regulates cocaine reinforcement, seeking, and abuse. Zn2+ is an essential element that binds to DAT, but the in vivo relevance of this is unknown. We found that cocaine use in humans correlated with Zn2+ content in the striatum, a brain region with high DAT density. In mice, cocaine increased synaptic Zn2+ release in the striatum. Striatal Zn2+ increased cocaines affinity and in vivo potency at the DAT and was required for cocaine-induced DAT upregulation. Finally, genetic or dietary Zn2+ manipulations modulated cocaine efficacy across different behavioral paradigms. These findings reveal new insights into cocaines pharmacological mechanism of action and establish synaptic Zn2+ as a critical environmentally-derived regulator of cocaine abuse vulnerability. Collectively, these data reveal the underlying molecular mechanism at DAT that may be leveraged to rationally optimize leads for the treatment of psychostimulant use disorders.

多巴胺 (DA) 转运蛋白 (DAT) 是滥用的可卡因等精神兴奋剂的主要药理学靶点，也是莫达非尼 (MOD) 等处方药的主要药理学靶点，在临床或临床前研究中，莫达非尼 (MOD) 几乎没有显示出滥用倾向。最近，我们探索了 MOD 的神经化学和行为作用，以更好地表征其非典型精神兴奋剂特征。 我们发现，MOD 在刺激伏隔核壳 (NAS) 和核心 (NAC) DA 水平方面的效力和功效低于可卡因，但与滥用的精神兴奋剂不同，伏隔核亚区域之间没有统计学上显着的区域差异。在药物歧视研究中，MOD 显示出与可卡因类似的主观效应，其剂量较低且起效时间比根据其 DA 效应预期的要早。这些结果表明，非 DA 依赖性作用可能在其独特的药理学特征中发挥了作用。 为了发现这些 MOD 作用的潜在非多巴胺能机制，我们将其行为和神经化学效应与哌甲酯（另一种临床批准的抑制 DA 神经元再摄取的药物）的行为和神经化学效应进行了比较。我们发现，与可卡因类似，哌醋甲酯（而非 MOD）在 Sprague-Dawley 大鼠中维持静脉自我给药。 MOD 和哌醋甲酯预处理均增强了可卡因的自我给药。自行服用剂量的可卡因会刺激中脑边缘的 DA 水平。这种作用被哌醋甲酯增强，但不是 MOD 预处理增强的，表明哌醋甲酯具有 DA 依赖性作用，但 MOD 没有。已知 MOD 通过作用于间隙连接来促进电紧张神经元耦合。 Carbenoxolone 是一种间隙连接抑制剂，可以拮抗 MOD，但不能拮抗哌醋甲酯对可卡因自我给药的增强作用。我们的结果表明，MOD 与可卡因和哌醋甲酯具有相同的机制，但具有独特的药理学特征，包括促进电紧张耦合和降低滥用可能性，这可能会在未来可卡因使用障碍的治疗药物设计中得到利用。 尽管 MOD 可能被证明可用于治疗特定的成瘾人群（例如重度强效可卡因使用者，或没有酒精滥用合并症的可卡因和甲基苯丙胺成瘾者），但针对精神兴奋剂使用障碍的更广泛有效的药物仍然是一个未得到满足的医疗需求。为此，几种新合成的 MOD 类似物，例如 JJC8-091 和 JJC8-088，已在我们的临床前模型中进行了测试，作为治疗甲基苯丙胺 (METH) 和可卡因使用障碍的潜在药物。 JJC8-091 和 JJC8-088 单独进行评估，并与可卡因联合评估，以阐明与其不同行为特征相关的神经化学物质。尽管具有显着的结构相似性，JJC8-088 更像可卡因，比 JJC8-091 更有效且更有效地增加 NAS 中的细胞外 DA 浓度。相比之下，JJC8-091 不是自我给药的，并且可以有效阻止可卡因诱导的药物寻求恢复。电生理学实验证实，JJC8-091 在抑制可卡因介导的 DA 神经传递增强方面比 JJC8-088 更有效。此外，当 DAT-cre 小鼠的 VTA DA 神经元受到光学刺激时，JJC8-088 的刺激反应曲线产生显着的左移，与可卡因类似，而 JJC8-091 则使曲线向下移动，表明 DA 介导的大脑奖赏减弱。计算模型预测，虽然 JJC8-088 更喜欢或稳定 DAT 的外向构象（如可卡因），但 JJC8-091 却将 DAT 稳定为更封闭的构象。 最近，我们合作开展了一个与可卡因对体外和体内神经自噬的潜在影响相关的项目。自噬抑制剂，即羟氯喹和 SBI-0206965，可降低全身给予可卡因的运动刺激作用及其对小鼠细胞外 NAS DA 水平的相关刺激。可卡因诱导的自噬会降解 DA 转运蛋白，但不会降解 NAS 中的血清素。自噬抑制会损害小鼠的可卡因条件性位置偏好。这些发现表明 DAT 的自噬降解可调节可卡因的行为和神经化学作用。 我们的研究合作还包括研究 microRNA 系统对缺乏 translin/trax microRNA 降解酶的小鼠（Tsn KO 小鼠）神经元信号传导的作用。我们发现对精神兴奋剂的行为和神经化学反应发生了改变，并且在正常体重的情况下也出现了强烈的肥胖，这表明这种表型可能反映了所测试的精神兴奋剂的大脑水平升高。对野生型小鼠饮食引起的肥胖增加对大脑安非他明水平的影响的分析也表明，大脑安非他明水平与肥胖相关。 Tsn KO 小鼠或喂食高脂肪饮食的野生型小鼠表现出的肥胖增加与脑内安非他明水平升高相关。由于安非他明及其类似物被广泛用于治疗与肥胖相关的注意力缺陷障碍，因此有必要进行进一步的研究来评估肥胖对这些患者安非他明水平的影响。 在最近的一次合作中，我们研究了锌在可卡因寻求和滥用脆弱性中的作用。可卡因通过阻断 DA 转运蛋白 (DAT) 来增加突触多巴胺 (DA)。这个过程调节可卡因强化、寻求和滥用。 Zn2+ 是与 DAT 结合的必需元素，但其体内相关性尚不清楚。我们发现人类吸食可卡因与纹状体中的 Zn2+ 含量相关，纹状体是 DAT 密度较高的大脑区域。在小鼠中，可卡因增加了纹状体中突触 Zn2+ 的释放。纹状体 Zn2+ 增加了可卡因对 DAT 的亲和力和体内效力，并且是可卡因诱导的 DAT 上调所必需的。最后，遗传或饮食中的 Zn2+ 操作可调节不同行为模式下的可卡因功效。这些发现揭示了对可卡因药理学作用机制的新见解，并将突触 Zn2+ 确立为可卡因滥用脆弱性的关键环境衍生调节剂。 总的来说，这些数据揭示了 DAT 的潜在分子机制，可用于合理优化治疗精神兴奋剂使用障碍的线索。