Second Generation Small Molecule Inhibitors of Botulinum Neurotoxins

描述（由申请人提供）：肉毒神经毒素（BoNT）是对我们国家安全最严重的生物恐怖威胁之一。由芽孢形成细菌肉毒梭菌、巴氏梭菌和丁酸梭菌分泌的BoNT是与肉毒中毒相关的弛缓性麻痹的原因。BoNT被CDC列为A类生物威胁，是生物毒素中毒性最大的，易于生产，可通过各种途径递送，包括食物掺入（固体和液体）和气溶胶分散。一旦酶已经进入神经元胞质溶胶，就没有治疗剂来对抗BoNT诱导的麻痹-此时唯一的治疗选择是在重症监护环境中不切实际的机械通气。该项目的长期目标是通过开发BoNT的有效小分子非肽抑制剂（SMNPI）作为治疗剂来解决这一公共卫生威胁，所述治疗剂将用作救援剂和药物。该提案的具体目标1 - 3集中于将我们的BoNT血清型A的前导uM范围SMNPI转化为在动物模型中有效的低nM范围SMNPI。具体目标4集中于鉴定和开发在神经元测定中有效的BoNT血清型B的SMNPI，具体目标5涵盖BoNT血清型E的SMNPI的鉴定。最后，在具体目标6下，我们建议检查所有鉴定和开发的SMNPI对一种以上BoNT血清型的广谱抑制活性。为了实现项目目标，我们结合联合收割机三维药效团为基础的方法和合成有机化学策略。具体地，这样的方法结合联合收割机X射线晶体学、体外和体内生物学测试、分子建模和3-D数据库挖掘以及有机化学来指导SMNPI发现和优化（即，良好的体外效力、良好的ADMET特征、降低的毒性和在动物模型中增强的体内效力）。相关性（参见说明）：植物神经毒素（Botanical neurotoxins，BoNTs）是地球上最强的毒素，能够被用作生物恐怖装置。目前还没有治疗方法来对抗由BoNT中毒引起的麻痹引起的不可避免的窒息和某些死亡。我们建议使用治疗上可行的化学物质作为药物。我们的提案包括已经具有针对两种血清型的BoNT中毒过程的关键组分的活性的分子。

DESCRIPTION (provided by applicant): Botulinum neurotoxins (BoNTs) represent one of the most serious bioterror threats to our national security. Secreted by spore forming bacteria Clostridium botulinum, baratii, and butyricium, BoNTs are responsible for the flaccid paralysis associated with botulism. Listed as category A biothreats by the CDC, BoNTs are the most toxic of biological toxins, are easily produced, and may be delivered by various routes including food spiking (solid and liquid) and aerosol dispersion. There are no therapeutics to counter BoNT induced paralysis once the enzyme has entered the neuronal cytosol - at this time the only treatment option is impractical mechanical ventilation in a critical care setting. The long-term objective of this project is to address this public health threat by developing potent small molecule, non-peptidic, inhibitors (SMNPIs) of BoNTs as therapeutics that will serve as both rescue agents and prophylactics. Specific aims 1 - 3 of the proposal focus on translating our lead uM range SMNPIs of BoNT serotype A into low nM range SMNPIs that are effective in an animal model. Specific aim 4 concentrates on identifying and developing SMNPIs of BoNT serotype B that are effective in a neuronal assay, and specific aim 5 covers the identification of SMNPIs of BoNT serotype E. Finally, under specific aim 6, we propose examining all identified and developed SMNPIs for broad spectrum inhibitory activity against more than one BoNT serotype. To achieve the project goals we combine three-dimensional pharmacophore-based methods and synthetic organic chemistry strategies. Specifically, such methods combine X-ray crystallography, in vitro and in vivo biological testing, molecular modeling and 3-D database mining, and organic chemistry to guide SMNPI discovery and optimization (i.e., good in vitro potencies, good ADMET profiles, reduced toxicities, and enhanced in vivo efficacies in an animal model). RELEVANCE (See instructions): Botulinum neurotoxins (BoNTs) are the most potent toxins on the planet and are capable of being used as bioterror devises. There is currently no therapeutic to counter the inevitable suffocation and certain death resulting from the paralysis induced by BoNT poisoning. We propose the use of therapeutically viable chemicals as drugs. Our proposal includes molecules that already possess activity against critical components of the BoNT intoxication process for two serotypes.