Targeting trypanosomatid deoxyhypusine synthase

靶向锥虫脱氧马匹氨酸合酶

基本信息

批准号：
9813821
负责人：
Margaret A. Phillips
金额：
$ 47.45万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-12-15 至 2021-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9813821
关键词：
Active Sites African Trypanosomiasis Amino Acids Basic Amino Acids Biochemical Biological Assay Biological Process Brain Cells Cellular Assay Chagas Disease Chemicals Disease Drug Kinetics Drug Targeting Entamoeba Enzymes Eukaryota Eukaryotic Cell Eukaryotic Initiation Factors Evaluation Genetic Translation Goals Growth Human Human Cell Line Impairment In Vitro Infection Lead Leishmania Leishmaniasis Libraries Link Lysine Mass Spectrum Analysis Metabolism Modeling Modification Mus Parasites Pathogenicity Penetration Permeability Pharmaceutical Chemistry Pharmaceutical Preparations Pharmacotherapy Phase Polyamines Property Series Solubility Spermidine Structure Testing Toxic effect Trypanosoma brucei brucei Trypanosoma cruzi Validation base cell growth cell killing combat cytotoxicity deoxyhypusine synthase gene product high throughput screening hypusine in vitro Assay in vivo in vivo evaluation inhibitor/antagonist lead optimization meetings mouse model neglected tropical diseases novel novel strategies paralogous gene pre-clinical programs resistance mechanism screening program small molecule small molecule inhibitor translation factor treatment program

项目摘要

Project Description. Trypanosomatid parasites are the causative agents of human African trypanosomiasis (HAT), Leishmaniasis and Chagas disease, all of which are listed by the WHO as Neglected tropical diseases (NTDs). Collectively 18-20 million people are infected with one of these parasites, yet drug therapies remain inadequate for all three diseases. Discovery of a drug-target that could be exploited against all three parasites, while not showing toxicity against the host, would provide a robust new approach to combat these diseases. Eukaryotes universally require a translation factor called eIF5A for cell growth. To be active eIF5A must be post-translationally modified on a conserved lysine reside to generate a novel amino acid called hypusine. The hypusine modification of eIF5A is catalyzed by deoxyhypusine synthase (DHS) using spermidine as a substrate. DHS is an essential enzyme in all eukaryotes including the trypanosomatids. We previously demonstrated that DHS from trypanosomatids and Entamoeba have uniquely evolved to require heterotetramer formation between two paralogous gene products to generate the active enzyme. This unusual configuration of these parasite DHSs suggests that it may be feasible to identify selective inhibitors of the parasite enzymes that don't inhibit human DHS. The goal of this proposal is to determine if drug-like inhibitors of DHS that are selective for the trypanosomatid enzymes can be identified and if so to advance them during a lead optimization program for the treatment of HAT. In the R21 phase of this proposal we plan to develop a high throughput screen (HTS) compatible assay for T. brucei DHS and to use this assay to screen the UT Southwestern 200,000 compound library for T. brucei DHS inhibitors. We will perform hit validation on identified inhibitors and determine if the identified inhibitors show good selectivity versus human DHS. If trypanosomatid specific DHS inhibitors with good drug like properties can be identified than in the R33 phase of the proposal we plan a hit to lead optimization of at least one series with appropriate properties to be advanced for the treatment of HAT. Identified DHS inhibitors will also be tested at various stages during hit validation and lead optimization against T. cruzi and Leishmania to determine if they have the potential to be developed as a broad-spectrum treatment for all three trypanosomatid-based diseases.

项目描述。锥虫寄生虫是人类非洲锥虫病 (HAT) 的病原体，利什曼病和查加斯病，均被世界卫生组织列为被忽视的热带病（被忽视的热带病）。总共有 18-2000 万人感染了其中一种寄生虫，但尚无药物治疗仍然不足以治疗所有三种疾病。发现可用于对抗所有疾病的药物靶点三种寄生虫虽然没有表现出对宿主的毒性，但将提供一种强有力的新方法对抗这些疾病。真核生物普遍需要一种称为 eIF5A 的翻译因子来促进细胞生长。要激活 eIF5A，必须对保守的赖氨酸残基进行翻译后修饰，以生成一种新的氨基酸，称为马尿苷。 eIF5A 的前尿嘧啶修饰由脱氧前尿嘧啶催化使用亚精胺作为底物的合成酶（DHS）。 DHS 是所有真核生物的必需酶，包括锥虫纲。我们之前证明来自锥虫和内阿米巴的 DHS 独特地进化到需要两个旁系同源基因产物之间形成异四聚体才能产生活性酶。这些寄生虫 DHS 的这种不寻常的配置表明，鉴定出不会抑制人类 DHS 的寄生虫酶的选择性抑制剂。此举的目标建议确定 DHS 药物样抑制剂是否对锥虫酶具有选择性可以被识别，如果是的话，可以在治疗 HAT 的先导优化计划中推进它们。在该提案的 R21 阶段，我们计划开发一种高通量筛选 (HTS) 兼容的检测方法 T. brucei DHS 并使用此测定法筛选 UT Southwestern 200,000 化合物库中的 T. brucei。布氏 DHS 抑制剂。我们将对已识别的抑制剂进行命中验证，并确定是否与人类 DHS 相比，已鉴定的抑制剂表现出良好的选择性。如果锥虫特定 DHS 与我们计划的提案的 R33 阶段相比，可以识别出具有良好药物特性的抑制剂成功引导至少一个系列的优化，并为该系列提供适当的属性 HAT 的治疗。已确定的 DHS 抑制剂也将在命中验证期间的各个阶段进行测试并针对克氏锥虫和利什曼原虫进行优化，以确定它们是否有潜力开发为针对所有三种锥虫疾病的广谱治疗方法。