Multi-targeted Countermeasures against Acute and Delayed Effects of OP Exposure

针对 OP 暴露的急性和迟发效应的多目标对策

• 批准号: 8589969
• 负责人: John A Butera
• 金额: $ 37.45万
• 依托单位: HAGER BIOSCIENCES, LLC
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-20 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8589969
• 关键词: Acetylcholine; Acetylcholinesterase; Acetylcholinesterase Inhibitors; Acute; Address; Anti-Cholinergics; Anticonvulsants; Anxiety; Attenuated; Axon; Benzamides; Benzodiazepines; Binding; Blood; Blood - brain barrier anatomy; Brain Injuries; Cardiac; Cessation of life; Charge; Chemicals; Cleaved cell; Clinical; Cognitive deficits; Demyelinations; Diabetes Mellitus; Disease; Distress; Dose; Drug Interactions; Drug Kinetics; Emotional Disturbance; Equilibrium; Exposure to; Eye; Floods; Free Radical Formation; Freedom; Generations; Goals; Grant; Health Personnel; Hemorrhagic Shock; Hydrolysis; In Vitro; Inflammation; Intellectual Property; Intoxication; Ischemia; Kinetics; Late-Onset Disorder; Lead; Learning Disabilities; Libraries; Ligands; Link; Malignant Neoplasms; Measures; Mental Depression; Metabolism; Metric; Military Personnel; Mind; Mitochondria; Modality; Molecular Target; Mucous body substance; Muscarinic Acetylcholine Receptor; Muscle; National Institute of Neurological Disorders and Stroke; Nature; Nerve; Nerve Degeneration; Neuraxis; Neurons; Neuropathy; Neuroprotective Agents; Niacinamide; Nicotinic Receptors; Organophosphates; Oxidative Stress; Oximes; Paralysed; Parents; Pathway interactions; Penetration; Permeability; Pesticides; Pharmaceutical Chemistry; Pharmaceutical Preparations; Pharmacologic Substance; Phase; Play; Poly(ADP-ribose) Polymerases; Post-Traumatic Stress Disorders; Process; Property; Rattus; Reporting; Risk; Rodent Model; Safety; Sarin; Seizures; Series; Serine; Site; Small Business Innovation Research Grant; Small Business Technology Transfer Research; Soman; Staging; Status Epilepticus; Stroke; Synapses; Syndrome; Terrorism; Therapeutic; Toxic effect; Toxin; Treatment outcome; Unconscious State; United States National Institutes of Health; Vision; Work; base; central nervous system injury; cholinergic; design; drug development; drug discovery; drug market; emergency service responder; excitotoxicity; experience; improved; in vivo; inhibitor/antagonist; innovation; irritation; knowledge base; large scale production; late disease onset; nerve agent; nervous system disorder; neuroprotection; neuropsychiatry; novel; organophosphate poisoning; pharmacophore; pill; pre-clinical; progressive neurodegeneration; prototype; public health relevance; receptor; response; scaffold; screening; small molecule; tabun; tool; toxic organophosphate insecticide exposure; weapons of mass destruction

DESCRIPTION (provided by applicant): Organophosphate (OP) nerve agents have been deployed as weapons of mass destruction in warfare arenas and in recent terrorist attacks; posing significant risks to military personnel, civilians, first responders and healthcare provider. The classic OP nerve agents such as sarin, soman, tabun, and VX, along with related OP pesticides represent some of the most toxic materials known to humankind. Their toxicity is principally due to their ability to irreversibly bind to acetylcholinesterase (AChE) in the CNS and blood. This process deactivates AChE and renders it unable to process acetylcholine in the synapse; resulting in excitotoxic levels of acetylcholine and hypersensitization of muscarinic and nicotinic receptors. This overload of excitotoxic chemicals incapacitates the victim via cholinergic toxidrome, resulting in seizures, paralysis, mucous secretions, eye irritation, cardiorespiratory depression, GI distress, and eventually, death. Additionally, OP exposure initiates a sequelae of mechanisms leading to delayed neurodegeneration in the CNS; including heightened excitotoxicity at other receptors and transporters and progressive demyelination and degradation of nerve axons. Cases of exposure to OP agents, whether intentional (warfare or terrorism) or accidental (pesticide mishandling), number in excess of 2 million per year; resulting in the deaths of several hundred thousand victims per year worldwide. Currently available countermeasures for OP poisoning involve the simultaneous administration (via autoinjectors) of three different agents: (1) an anticholinergic agent, (2) an anticonvulsant agent, and (3) a pyridinium oxime-bearing AChE reactivator. While the anticholinergic and anticonvulsant agents work to block the effects of excess acetylcholine, the oxime-based reactivator plays the key role of cleaving the phosphorylated serine esteratic site to release the active AChE molecule. However, currently used agents possess poor ADME properties due to their charged nature. Thus, significant deficiencies in current OP countermeasures include: (1) the requirement for simultaneous multi-therapeutic modality treatments with complicated dosing regiments, (2) poor CNS-permeability of currently used pyridinium oximes, and (3) the complete lack of efficacy in any of the current treatments to counteract the long-term neurodegenerative sequelae that manifests after prolonged exposure to nerve agents. It has been established that inhibitors of poly(ADP-ribose)polymerase-1 (PARP-1) are useful neuroprotective agents especially when the neurodegeneration is caused by excitotoxic insult. Inhibitors of PARP-1 have been investigated pre-clinically and clinically for cardiac ischemia, hemorrhagic shock syndrome, stroke, traumatic CNS injury, diabetes, inflammation, and cancer. The prototype PARP-1 inhibitor, benzamide, has been shown to be neuroprotective against soman-induced seizure-related brain damage in the rat. It has been recently suggested that the inherent multiple-pathway complexity of OP-induced long-term neuropathy disorders should be countered with a similarly multi-faceted treatment approach. Hence, the design of small molecules possessing dual- pharmacophores to simultaneously modulate two discreet molecular targets is an important strategy in drug discovery. There is a clear and proven advantage to having a single agent that can modulate multiple targets simultaneously as compared to either a cocktail or a single pill formulated with multi-component agents. A dual acting single agent designed by overlapping pharmacophores would have better ligand efficiency (e.g. reduced MW, LogP) and would provide one dimensional metabolism, pharmacokinetics, and safety profiles as opposed to co-administering two drugs where development metrics are complicated due to possible drug-drug interactions and differential kinetic profiles. It is the aim of this project to discover novel and mechanisticaly unique dual- acting agents which would represent a breakthrough innovative countermeasure against OP chemical threats. Thus, the first innovative aspect of this application is to discover a novel PARP-1 inhibitor that also possesses dual activity as an AChE-reactivator; via merging two known pharmacophores in the same molecule, to provide multiple pharmacological effects and a superior overall pharmacological profile to treat OP-poisoning. A single agent with dual PARP-1 inhibition and AChE-reactivating activity would represent an innovative and novel treatment for OP poisoning because: (1) the PARP-1 inhibition activity would attenuate the excitotoxic cascade of free-radical formation by preserving mitochondrial function and reducing oxidative stress and energetic crisis, and (2) the oxime-bearing fragment would salvage the OP-bound inactivated AChE and thereby reduce excitotoxic acetylcholine levels. The second innovative aspect of our approach is the design and synthesis of dual agents with suitable pharmaceutical profiles, such that they will be able to cross the blood brain barrier, a desired feature that is lacking from current AChE reactivators. The successful identification of two in vitro optimized series of novel, dual-active PARP-1 inhibitor/AChE reactivators in this Phase 1 campaign would provide critical tool compounds for in vivo PK assessment and POC studies in rodent models of OP-intoxication and neurodegeneration. This would set the stage for a final lead optimization campaign focused on identifying pre- clinical leads with well-balanced in vivo PK parameters during an SBIR Phase 2 continuing grant.

描述（由申请人提供）：有机磷（OP）神经毒剂已被用作战争领域和最近的恐怖袭击中的大规模杀伤性武器；对军事人员、平民、急救人员和医疗保健提供者构成重大风险。经典的 OP 神经毒剂，如沙林、索曼、塔崩和 VX，以及相关的 OP 农药代表了人类已知的一些毒性最强的物质。它们的毒性主要是由于它们能够不可逆地与中枢神经系统中的乙酰胆碱酯酶 (AChE) 结合， 血。这个过程使 AChE 失活，使其无法在突触中处理乙酰胆碱；导致乙酰胆碱的兴奋性毒性水平和毒蕈碱和烟碱受体的超敏化。这种过量的兴奋性毒性化学物质会通过胆碱能中毒反应使受害者丧失行为能力，导致癫痫、瘫痪、粘液分泌、眼睛刺激、心肺抑制、胃肠道不适，最终导致死亡。此外，OP暴露会引发导致中枢神经系统迟发性神经变性的机制后遗症。包括其他受体和转运蛋白的兴奋性毒性增强以及神经轴突的进行性脱髓鞘和降解。接触有机磷农药的案例，无论是故意（战争或恐怖主义）还是意外（农药处理不当），每年数量超过 200 万起；结果 全世界每年有数十万受害者死亡。目前针对 OP 中毒的可用对策包括同时施用（通过自动注射器）三种不同的药物：(1) 抗胆碱能药物，(2) 抗惊厥药物，以及 (3) 含有吡啶鎓肟的乙酰胆碱酯酶再激活剂。虽然抗胆碱能药物和抗惊厥药物可以阻断过量乙酰胆碱的作用，但基于肟的再激活​​剂在裂解磷酸化丝氨酸酯位点以释放活性 AChE 分子方面发挥着关键作用。然而，目前使用的试剂由于其带电性质而具有较差的 ADME 性能。因此，当前OP对策的显着缺陷包括：（1）需要同时采用复杂的给药方案进行多种治疗方式治疗，（2）目前使用的吡啶鎓肟的中枢神经系统渗透性差，以及（3）目前的任何治疗方法都完全缺乏对抗长期暴露于神经后出现的长期神经退行性后遗症的功效。 代理。已经确定，聚（ADP-核糖）聚合酶-1（PARP-1）抑制剂是有用的神经保护剂，尤其是当神经变性是由兴奋性毒性损伤引起时。 PARP-1 抑制剂已针对心脏缺血、失血性休克综合征、中风、创伤性中枢神经系统损伤、糖尿病、炎症和癌症进行了临床前和临床研究。 PARP-1 抑制剂原型苯甲酰胺已被证明对大鼠中梭曼诱发的癫痫相关脑损伤具有神经保护作用。最近有人建议，OP 引起的长期神经病变疾病固有的多途径复杂性应该用类似的多方面治疗方法来应对。因此，设计具有双药效团以同时调节两个离散分子靶标的小分子是药物发现的重要策略。与由多组分药物配制的鸡尾酒或单一药丸相比，可以同时调节多个靶标的单一药物具有明显且经过证明的优势。由重叠药效团设计的双重作用单药将具有更好的配体效率（例如降低的MW、LogP），并且将提供一维代谢、药代动力学和安全性特征，而不是同时施用两种药物，在两种药物中，由于可能的药物相互作用和不同的动力学特征，开发指标变得复杂。该项目的目的是发现新颖且机制独特的双重作用剂，这将代表针对OP化学威胁的突破性创新对策。因此，该应用的第一个创新方面是发现 新型 PARP-1 抑制剂，还具有乙酰胆碱酯酶 (AChE) 重激活剂的双重活性；通过将两个已知的药效团合并在同一分子中，提供多种药理作用和优越的整体药理特征来治疗 OP 中毒。具有双重 PARP-1 抑制和 AChE 重激活活性的单一药物将代表一种创新且新颖的 OP 中毒治疗方法，因为：（1）PARP-1 抑制活性将通过保留线粒体功能并减少氧化应激和能量危机来减弱自由基形成的兴奋性毒性级联，以及（2）带有肟的片段将挽救 OP 结合的失活 AChE 从而降低兴奋毒性乙酰胆碱水平。我们方法的第二个创新方面是设计和合成具有合适药物特性的双重药物，使它们能够穿过血脑屏障，这是当前乙酰胆碱酯酶再激活剂所缺乏的所需功能。在这一阶段的 1 期研究中成功鉴定了两个体外优化系列的新型双活性 PARP-1 抑制剂/AChE 重激活剂，将为 OP 中毒和神经变性啮齿动物模型的体内 PK 评估和 POC 研究提供关键的工具化合物。这将为最终的先导化合物优化活动奠定基础，该活动的重点是在 SBIR 第 2 期持续资助期间确定具有良好平衡的体内 PK 参数的临床前先导化合物。