Improved Therapeutics for the Resurrection of the Aged Form of Acetylcholinesterase

老化乙酰胆碱酯酶复活的改进疗法

• 批准号: 9977281
• 负责人: Christopher M. Hadad
• 金额: $ 40.58万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-15 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9977281
• 关键词: Acetylcholine; Acetylcholinesterase; Active Sites; Aging; Ammonium; Back; Binding; Binding Sites; Biochemical; Chemical Agents; Chemical Warfare Agents; Chemicals; Cleaved cell; Complement; Computing Methodologies; Country; Crystallization; Docking; Enzymes; Event; Exposure to; Family; Human; In Vitro; Kinetics; Lead; Libraries; Ligands; Mechanics; Methods; Military Personnel; Molecular; Neuromuscular Junction; Organic Synthesis; Organophosphorus Compounds; Oximes; Peripheral; Pesticides; Pharmaceutical Preparations; Process; Property; Proteomics; Reporting; Serine; Societies; Soman; Structure; Testing; Therapeutic; Variant; adduct; age effect; aged; cholinergic; design; humanized mouse; improved; in silico; in vivo; mass casualty; medical countermeasure; methylphosphonate; molecular dynamics; mouse model; nerve agent; novel; quantum; quinone methide; receptor; scaffold; screening; small molecule libraries; success; toxicant

One of the major deficiencies of current medical countermeasures is that current oximes cannot reactivate nerve agent-inhibited acetylcholinesterase (AChE) that has aged after exposure to organophosphorus G- and V-type chemical nerve agents. Our team has demonstrated the first, and only, compounds that have the capability to “resurrect” in vitro the methylphosphonate-aged form of AChE to an active, native state. We posit that this resurrection accomplishes two distinct steps – first, to realkylate the anionic aged form back to a neutral, phosphylated (inhibited) serine residue and then to reactivate the inhibited form back to the native AChE. This proposal focuses on expanding on these successful chemical frameworks in order to identify even more efficacious drug-like molecules that will enable the aged form of AChE to be resurrected in vivo. Using various quinone methide precursor (QMP) frameworks, we will use computational and experimental approaches to prepare a chemical library and then to screen these compounds for efficacy in resurrecting the aged form of AChE back to native activity. There are no approved countermeasures that can resurrect the aged form of AChE to its active form; however, resurrection of aged AChE is the holy grail against OP exposure. If realkylation of aged AChE can occur, then AChE can be fully rejuvenated as oximes (and other reactivators) exist that are potent nucleophiles for cleaving the O–P bond of the phosphylated serine, thereby reforming active AChE. Thus, the objective of this proposal is to expand on our successful chemical frameworks to react selectively with aged AChE to form stable alkylphosphonate-AChE adducts that can then be reactivated to the native state, thereby reversing the effects of aging by chemical nerve agents. The design of alkylating compounds will be guided by state-of-the-art computational methods (molecular dynamics, molecular docking, and quantum mechanical methods) that predict the ligand-receptor interactions of alkylating compounds with aged AChE. Using in silico guidance, libraries of alkylating quinone methide precursor (QMP) compounds will be synthesized, and then tested in a kinetic screening process, and complemented by mass spectrometric and proteomic studies. The best lead compounds will be evaluated for their in vitro drug-like properties and tested in vivo in a humanized mouse model for AChE.

当前医学对策的主要缺陷之一是当前肟不能 重新激活神经毒剂抑制的乙酰胆碱酯酶（AChE）， 有机磷G型和V型化学神经毒剂。我们的团队已经展示了第一个， 只有那些能够在体外“复活”甲基膦酸酯老化的化合物， AChE的形式到一个积极的，自然的状态。我们认为这次复活完成了两个不同的步骤 - 首先，将阴离子老化形式再烷基化回到中性磷酸化（抑制）丝氨酸残基， 然后将被抑制的形式重新激活为天然AChE。该提案的重点是扩大 这些成功的化学框架，以确定更有效的药物样分子， 将使老化的乙酰胆碱酯酶在体内复活。使用各种醌甲基化物前体 (QMP)框架，我们将使用计算和实验方法来制备一种化学物质 库，然后筛选这些化合物的功效，使AChE的老化形式恢复到 本土活动。 目前还没有得到批准的对策可以使老化的乙酰胆碱酯酶恢复到其活性形式; 然而，老化AChE的复活是对抗OP暴露的圣杯。如果老化AChE的再烷基化 可以发生，那么AChE可以完全恢复活力，因为肟（和其他再活化剂）存在， 亲核试剂用于切割磷酸化丝氨酸的O-P键，从而重整活性AChE。 因此，本提案的目的是扩大我们成功的化学框架， 选择性地与老化的AChE形成稳定的烷基膦酸酯-AChE加合物， 重新激活到自然状态，从而逆转化学神经毒剂的衰老效应。 烷基化化合物的设计将由最先进的计算方法（分子 动力学、分子对接和量子力学方法）来预测配体-受体 烷基化化合物与老化AChE的相互作用。使用计算机指导，烷基化库 醌甲基化物前体（QMP）化合物将被合成，然后在动力学筛选中进行测试 过程，并辅以质谱和蛋白质组学研究。最好的铅化合物 将评估它们的体外药物样性质，并在人源化小鼠模型中进行体内测试， 疼.