Optimization of small molecule probes

小分子探针的优化

• 批准号: 8440355
• 负责人: Stephen F Traynelis
• 金额: $ 22.46万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-03-08 至 2015-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8440355
• 关键词: Acids; Address; Animal Behavior; Animal Disease Models; Animal Model; Binding; Biological Assay; Brain; Chemicals; Chemosensitization; Cognition; Communication; Data; Development; Disease; Drug Kinetics; Electrodes; Family member; Funding; Gated Ion Channel; Glutamate Receptor; Glutamates; Glycine; Goals; Grant; Half-Life; In Vitro; Lead; Learning; Ligands; Mediating; Memory; Mental Depression; Mental Health; Metabolic; Modeling; Modification; Molecular Probes; Moods; N-Methyl-D-Aspartate Receptors; N-Methylaspartate; NR1 gene; National Institute of Mental Health; Nervous system structure; Neuraxis; Neurons; Oocytes; Pharmaceutical Chemistry; Plasma; Play; Property; Pump; Recombinants; Regulation; Role; Schizophrenia; Site; Solubility; Spinal Cord; Synaptic Transmission; System; Testing; Tetrahydroisoquinolines; Therapeutic Agents; Work; analog; experience; ifenprodil; inhibitor/antagonist; nervous system disorder; neuropsychiatry; neurotoxicity; next generation; novel; postsynaptic; receptor; receptor function; research study; response; scaffold; screening; small molecule; tool; voltage clamp

DESCRIPTION (provided by applicant): N-methyl-D-aspartate (NMDA) receptors are postsynaptic ligand-gated ion channels that mediate excitatory synaptic transmission in the CNS. NMDA receptors are heteromultimers comprised of 2 glycine-binding NR1 subunits and 2 glutamate-binding NR2 subunits, of which there are four types (NR2A,B,C,D). NMDA receptors are involved in normal brain functions such as development, learning, and memory. In addition, NMDA receptor hypo-function may contribute to neuropsychiatric disorders such as schizophrenia, which has lead to the hypothesis that potentiation of NMDA receptor function could be therapeutically useful. However, no small molecule NMDA receptor potentiators exist with which to obtain proof-of-concept data. Given the lack of subunit- selective tool compounds, our objective in this proposal (in response to PAR-09-251 "Optimization of small molecule probes for the nervous system", a reissue of RFA-NS-09-003) is to identify potent, subunit-selective potentiators of NMDA receptors that can be used to test specific hypotheses about NMDA receptor function in neurological diseases. To accomplish this, we developed an assay for non-competitive allosteric modulators of NMDA receptors and screened ~100,000 compounds. We identified 6 distinct but related molecules that act at a similar site to potentiate NR2C/D-containing NMDA receptor function; one scaffold appears to favor NR2C potentiation. Our working hypothesis is that these multiple scaffolds can serve as a starting point for the development of potent subunit- selective NMDA receptor potentiators. We propose to use medicinal chemistry to develop a compound with an EC50 value below 300 nM, maximal potentiation of > 2.5-fold, selectivity against other glutamate receptors > 200-fold, solubility > 10-fold EC50, lack of neurotoxicity and selectivity against 72 other CNS receptors, channels, and pumps of between 30-1000 fold. Experiments will address two questions: 1. What structural features control potency and efficacy of NR2C/D-selective NMDA receptor potentiators ? We will use parallel medicinal chemistry approaches to synthesize and test 200 analogues per year, a number supported by our preliminary data. The EC50 value for each compound will be determined at recombinant NR1/NR2A, NR1/NR2B, NR1/NR2C, NR1/NR2D, GluR1 receptors using 14 automated two-electrode voltage-clamp recording systems that can record/analyze concentration-effect curves for > 500 compounds/yr. Preliminary studies have identified several regions of the scaffold that control potency and subunit-selectivity with available chemical space. 2. What are the off-target liabilities and pharmacokinetic properties of NR2C/D potentiators? We will determine solubility and metabolic stability for all active compounds, and screen the best compounds at key decision points and again at the completion of the study against 72 receptors, channels, and transporters using a combination of automated multi-well assays both in the lab and at an NIMH-funded off-target screening center. This information will help to identify the best scaffold to pursue (year-1) as well as characterize the two best compounds to emerge from this study (year-2). We will evaluate plasma half-life, brain:plasma ratio, and neurotoxicity in vitro.

描述（由申请人提供）：N-甲基-D-天冬氨酸（NMDA）受体是突触后配体门控离子通道，介导中枢神经系统中的兴奋性突触传递。 NMDA受体是由2个甘氨酸结合NR1亚基和2个谷氨酸结合NR2亚基组成的异多聚体，有四种类型（NR2A、B、C、D）。 NMDA 受体参与正常的大脑功能，如发育、学习和记忆。此外，NMDA 受体功能低下可能会导致精神分裂症等神经精神疾病，这导致了这样的假设：NMDA 受体功能的增强可能具有治疗作用。然而，尚不存在可用于获得概念验证数据的小分子 NMDA 受体增强剂。鉴于缺乏亚基选择性工具化合物，我们在本提案中的目标（响应 PAR-09-251“神经系统小分子探针的优化”，RFA-NS-09-003 的重新发布）是确定NMDA 受体的有效亚基选择性增强剂，可用于测试有关神经系统疾病中 NMDA 受体功能的特定假设。为了实现这一目标，我们开发了一种 NMDA 受体非竞争性变构调节剂检测方法，并筛选了约 100,000 种化合物。我们鉴定了 6 种不同但相关的分子，它们作用于相似的位点以增强包含 NR2C/D 的 NMDA 受体功能；一种支架似乎有利于 NR2C 增强。我们的工作假设是，这些多重支架可以作为开发有效的亚基选择性 NMDA 受体增强剂的起点。我们建议使用药物化学来开发一种化合物，其EC50值低于300 nM，最大增效> 2.5倍，对其他谷氨酸受体的选择性> 200倍，溶解度> 10倍EC50，缺乏神经毒性和对72的选择性其他 CNS 受体、通道和泵的 30-1000 倍。实验将解决两个问题： 1. 哪些结构特征控制 NR2C/D 选择性 NMDA 受体增强剂的效力和功效？我们将使用并行药物化学方法每年合成和测试 200 种类似物，这一数字得到了我们初步数据的支持。每种化合物的 EC50 值将使用 14 个自动两电极电压钳记录系统在重组 NR1/NR2A、NR1/NR2B、NR1/NR2C、NR1/NR2D、GluR1 受体上测定，该系统可以记录/分析浓度效应曲线> 500 种化合物/年。初步研究已经确定了支架的几个区域，这些区域通过可用的化学空间控制效力和亚基选择性。 2. 脱靶负债和药代动力学特性是什么 NR2C/D 增效剂？我们将确定所有活性化合物的溶解度和代谢稳定性，并在关键决策点筛选最佳化合物，并在完成针对 72 种受体、通道和转运蛋白的研究后再次使用实验室中的自动化多孔测定组合筛选最佳化合物以及 NIMH 资助的脱靶筛查中心。这些信息将有助于确定要追求的最佳支架（第一年）以及表征本研究中出现的两种最佳化合物（第二年）。我们将评估血浆半衰期、脑：血浆比率和体外神经毒性。