Non-Tropane Irreversible Dopamine Transporter Ligands

非托烷不可逆多巴胺转运蛋白配体

• 批准号: 7707519
• 负责人: David John Lapinsky
• 金额: $ 16.63万
• 依托单位: DUQUESNE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7707519
• 关键词: 3-Dimensional; Address; Affinity; Alzheimer' s Disease; Amino Acids; Amphetamines; Attention deficit hyperactivity disorder; Azides; Behavioral; Benztropine; Binding; Binding Sites; Brain; Bupropion; Cell membrane; Chemicals; Classification; Cocaine; Commit; Complement; Crystallization; Data; Disease; Drug Design; Drug abuse; Elements; Gilles de la Tourette syndrome; Goals; Iodine; Isothiocyanates; Knowledge; Label; Lesch-Nyhan Syndrome; Leucine; Ligands; Link; Literature; Maps; Methylphenidate; Molecular Conformation; Neurons; Obesity; Parkinson Disease; Pharmaceutical Preparations; Photoaffinity Labels; Process; Property; Relative (related person); Research; Resolution; Rewards; Schizophrenia; Structure; Syndrome; Testing; Therapeutic; Tracer; Tropanes; Work; addiction; analog; base; combat; depression; design; dopamine transporter; drug discovery; functional group; inhibitor/antagonist; neurotoxic; preference; psychostimulant; public health relevance; pyrovalerone; receptor; research study; scaffold; stimulant abuse; three dimensional structure

DESCRIPTION (provided by applicant): Despite decades of committed research, no agents are clinically available to combat psychostimulant abuse and addiction. This prodigious void can be linked to sparse information on the 3-D structure and function of the dopamine transporter (DAT), which pharmacological and behavioral studies indicate is the brain receptor chiefly responsible for the reinforcing / reward properties associated with amphetamines and cocaine. There is a fundamental gap in understanding the mechanism of inhibitors and the structural elements and conformational states associated with the DAT. The long-term goal of our research is to develop chemical entities towards understanding how abused and therapeutic compounds interact with the DAT at the amino acid level. The objective of this particular application is to develop non-tropane irreversible ligands for mapping drug-binding pockets within the DAT. The central hypothesis is that non-tropane irreversible ligands can serve as complimentary probes to existing tropane-based (e.g., cocaine, benztropine) irreversible ligands for high- resolution elucidation of DAT 3-D structure. Guided by the literature and strong preliminary data, this central hypothesis will be tested by pursuing two specific aims: 1) Identify the structural elements of pyrovalerone- based irreversible ligands essential for labeling the DAT; and 2) Identify the structural elements of methylphenidate-based irreversible ligands for labeling the DAT. The specific hypotheses for these aims will test whether these non-tropane-based inhibitor scaffolds can be structurally modified to covalently label the DAT via an affinity or photoaffinity labeling experiment. Specifically, pyrovalerone and methylphenidate will be modified to contain an iodine as a tracer tag and either an aryl azide or aryl isothiocyanate as a reactive labeling functional group. The synthesized analogs will then be pharmacologically evaluated at the DAT in order to identify candidate probes for irreversible DAT labeling experiments. Additionally, a systematic design approach towards DAT irreversible ligands will be explored to address noted shortcomings associated with established tropane-based DAT irreversible ligands. The proposed research is significant because the binding sites and conformational preferences for pyrovalerone and methylphenidate as non-tropane therapeutically relevant compounds are unknown relative to tropane-based DAT ligands. A battery of developed probes based on these chemical scaffolds will advance the field towards rational structure-based drug design for a myriad of DAT-implicated disorders. PUBLIC HEALTH RELEVANCE: The proposed studies seek to provide chemical probes for 3-D mapping of drug-binding pockets within the dopamine transporter (DAT). The elucidation of details associated with DAT structure and function in turn will contribute to an understanding of how DAT protein components discriminate between therapeutic (e.g., benztropine, methylphenidate, bupropion) and abused (e.g., cocaine, amphetamine) compounds. Such findings will promote the rational design of safe and effective therapeutics for DAT-implicated conditions such as Parkinson's disease, Alzheimer's disease, schizophrenia, Tourette's syndrome, Lesch-Nyhan disease, attention deficit hyperactivity disorder, depression, obesity, and psychostimulant abuse.

描述（由申请人提供）：尽管进行了数十年的研究，但临床上尚无药物可用于对抗精神兴奋剂滥用和成瘾。这种巨大的空白可能与多巴胺转运蛋白 (DAT) 3D 结构和功能的稀疏信息有关，药理学和行为研究表明，多巴胺转运蛋白是大脑受体，主要负责与安非他明和可卡因相关的强化/奖励特性。在理解抑制剂的机制以及与 DAT 相关的结构元件和构象状态方面存在根本性的差距。我们研究的长期目标是开发化学实体，以了解滥用和治疗化合物如何在氨基酸水平上与 DAT 相互作用。这一特定应用的目的是开发非托烷不可逆配体，用于绘制 DAT 内的药物结合袋。中心假设是非托烷不可逆配体可以作为现有托烷类（例如可卡因、苯托品）不可逆配体的互补探针，用于高分辨率阐明 DAT 3-D 结构。在文献和强有力的初步数据的指导下，这一中心假设将通过追求两个具体目标进行检验：1）确定标记 DAT 所必需的基于吡咯戊酮的不可逆配体的结构元件； 2) 确定用于标记 DAT 的基于哌醋甲酯的不可逆配体的结构元件。针对这些目标的具体假设将测试这些非托烷类抑制剂支架是否可以进行结构修饰，以通过亲和或光亲和标记实验共价标记 DAT。具体来说，吡咯戊酮和哌醋甲酯将被修饰以含有碘作为示踪标签以及芳基叠氮化物或芳基异硫氰酸酯作为反应性标记官能团。然后，合成的类似物将在 DAT 上进行药理学评估，以确定用于不可逆 DAT 标记实验的候选探针。此外，还将探索 DAT 不可逆配体的系统设计方法，以解决与已建立的基于托烷的 DAT 不可逆配体相关的明显缺点。这项研究具有重要意义，因为相对于基于托烷的 DAT 配体，吡咯戊酮和哌醋甲酯作为非托烷治疗相关化合物的结合位点和构象偏好是未知的。一系列基于这些化学支架开发的探针将推动该领域朝着基于合理结构的药物设计的方向发展，以治疗多种 DAT 相关疾病。公共健康相关性：拟议的研究旨在为多巴胺转运蛋白 (DAT) 内药物结合袋的 3D 绘图提供化学探针。阐明与 DAT 结构和功能相关的细节反过来将有助于理解 DAT 蛋白成分如何区分治疗化合物（例如苯托品、哌醋甲酯、安非他酮）和滥用化合物（例如可卡因、安非他明）。这些发现将促进针对 DAT 相关疾病（如帕金森病、阿尔茨海默病、精神分裂症、抽动秽语综合征、Lesch-Nyhan 病、注意力缺陷多动障碍、抑郁症、肥胖和精神兴奋剂滥用）合理设计安全有效的疗法。