Early Stage Discovery of Natural Products Targeting Anaerobic Protozoal Pathogen

 描述（由申请人提供）：阴道毛滴虫是美国最流行的性传播感染性生物，约有700万人受影响。感染T.迷走神经病增加了患宫颈癌、不孕症、盆腔炎、前列腺炎和艾滋病的风险。硝基咪唑类药物是唯一一类可用于治疗滴虫病的药物，但它们具有几种严重的副作用。此外，对硝基咪唑类药物耐药性的出现和传播正成为人们关注的问题。因此，迫切需要开发新的治疗剂来对抗T。迷走神经和建议的研究，设计响应于这种RFA，提供了一种机制，发现和发展的生物活性分子，满足这一需要。药物发现计划的成功至关重要的是获得一个优秀的化学多样性物质库，这些物质非常适合成为早期阶段的线索。天然产物满足了这一基本要求，真菌的代谢产物以前没有被筛选出抗T。流浪汉因此，这项工作是创新的，因为我们将一个新的天然产品来源与一个新的高含量筛选系统，以确定有前途的生物活性物质从一个大型真菌次级代谢产物库。在本研究的R21阶段，我们将重点关注以下目标，以确保用于治疗T的新化合物。迷走神经感染：（i）实施高含量筛选系统，用于检测抑制T. 迷走神经活力;（ii）测试纯天然产品、预分级材料和次级代谢物富集的真菌提取物的一类库中的T.迷走神经;（iii）采用以真菌细胞为基础的反筛选，以从筛选中去除非选择性毒素;以及（iv）使用真菌分类学信息和次级代谢物去复制工具，以选择提取物和级分用于进一步研究。R21研究中出现的最有希望的药物将通过以下目的进行详细的R33研究：（i）从真菌级分和提取物混合物中纯化生物活性天然产物，（ii）建立生物活性代谢物的结构并确保用于生物评价的毫克量，（iii）开发一种补充的高含量筛选测定法，以评估每个击中分子对其他厌氧原生动物靶点的作用（贾第鞭毛虫和溶组织内阿米巴），和（iv）进行最有希望的命中分子的体外代谢研究，并测试其代谢物的毒性和生物活性。这些目标的成功实现有望产生一组集中的天然产物，抑制T。对人细胞毒性最小的迷走神经活性。预计将获得3-5种有希望的抑制剂，作为后续R 01/SBIR研究中立即研究的生物活性先导化合物。在R21/R33研究期间，对确保高质量生物活性化合物的关注预计将有助于产生一流的分子，用于治疗T。迷走神经和其他厌氧原生动物。

 DESCRIPTION (provided by applicant): Trichomonas vaginalis is the most prevalent sexually-transmitted infectious organism in the United States with roughly 7 million people affected. Individuals infected with T. vaginalis face an increased risk of cervical cancer, infertility, pelvc inflammatory disease, prostatitis, and susceptibility to HIV. The nitroimidazoles are the only class of drugs available to treat trichomoniasis, but they suffer from several serious side effects Additionally, the emergence and spread of resistance to nitroimidazoles is becoming a concern. Consequently, there is a critical need for the development of new therapeutic agents to combat T. vaginalis and the proposed studies, designed in response to this RFA, provide a mechanism for the discovery and development of bioactive molecules that meet this need. Vital to the success of a drug discovery program is access to an outstanding library of chemically diverse substances that are well suited to become early stage leads. Natural products meet this essential requirement with metabolites from fungi having not been previously screened against T. vaginalis. Thus, this work is innovative since we will couple a novel natural product source with a new high-content screening system to identify promising bioactive substances from a large fungal secondary metabolite library. During the R21 phase of this investigation, we will focus on the following objectives to secure new compounds for treating T. vaginalis infections: (i) implement a high-content screening system for the detection of natural products that inhibit T. vaginalis viability; (ii) test a one-of-a-kind library of pure natural products, pre-fractionated materials, and secondary-metabolite-enriched fungal extracts for inhibitors of T. vaginalis; (iii) employ a mammalian-cell-based counter-screen to remove non-selective toxins from screening; and (iv) use fungal taxonomic information and secondary metabolite dereplication tools to select extracts and fractions for further studies. The most promising agents emerging from the R21 studies will be subjected to detailed R33 studies via the following aims: (i) purify bioactive natural products from fungal fractions and extract mixtures, (ii) establish the structures of bioactive metabolites and secure milligram quantities for biological evaluation, (iii) develop a complimentary high-content screening assay to evaluate each hit molecule against additional anaerobic protozoan targets (Giardia intestinalis and Entamoeba histolytica), and (iv) conduct in vitro metabolism studies of the most promising hit molecules and test their metabolites for toxicity and bioactivity. The successful accomplishment of these aims is expected to yield a focused set of natural products that inhibit T. vaginalis viability with minimal toxicity to human cells. It is anticipated that 3-5 promising inhibitors will be obtained that will serve as bioactiv leads for immediate investigation during subsequent R01/SBIR studies. The focus on securing high-quality bioactive compounds during the R21/R33 study is anticipated to help generate first-in-class molecules with applications for treating T. vaginalis and other anaerobic protozoans.