Second Generation Small Molecule Inhibitors of Botulinum Neurotoxins

描述(申请人提供)：肉毒杆菌神经毒素(BoNTs)是对我国国家安全最严重的生物恐怖威胁之一。BoNTs由芽胞形成细菌肉毒杆菌、巴拉提菌和丁酸杆菌分泌，可引起肉毒杆菌中毒引起的迟缓性麻痹。BoNTs被美国疾病控制与预防中心列为A类生物制剂，是毒性最大的生物毒素，很容易产生，并可通过各种途径传递，包括食物添加(固体和液体)和气溶胶扩散。一旦这种酶进入神经细胞液，就没有治疗方法来对抗BONT引起的瘫痪--目前，唯一的治疗选择是在重症监护环境中进行不切实际的机械通气。该项目的长期目标是通过开发有效的BoNTs小分子非肽类抑制剂(SMNPI)来解决这一公共卫生威胁，作为治疗药物，既可用作救援剂，也可用作预防药物。该提案的具体目标1-3侧重于将我们的A型BONT血清型铅范围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试验中有效的B型BONT的SMNPI，而特异性目标5包括鉴定E型BONT的SMNPI。最后，在特异性目标6下，我们建议检查所有已鉴定和开发的SMNPI对不止一种BONT血清型的广谱抑制活性。为了实现项目目标，我们结合了基于三维药效团的方法和合成有机化学策略。具体地说，这些方法结合了X射线结晶学、体外和体内生物测试、分子建模和3-D数据库挖掘以及有机化学来指导SMNPI的发现和优化(即在动物模型中具有良好的体外效力、良好的适配性、降低毒性和增强体内疗效)。相关性(见说明)：肉毒杆菌神经毒素(BoNTs)是地球上最有效的毒素，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中毒导致的瘫痪所导致的不可避免的窒息和一定的死亡。我们建议使用治疗上可行的化学物质作为药物。我们的建议包括已经对两种血清型的BONT中毒过程的关键成分具有活性的分子。

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.