Characterization of activity and mechanism of novel fungicidal anti-cryptococcal molecules

新型杀菌抗隐球菌分子的活性和机制表征

基本信息

批准号：
9232052
负责人：
Damian J Krysan
金额：
$ 7.79万
依托单位：
UNIVERSITY OF ROCHESTER
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：
2016-03-01 至 2017-09-01
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9232052
关键词：
AIDS/HIV problem Address Affect Africa South of the Sahara Algorithms Alternative Therapies Amphotericin B Animal Model Anti-Retroviral Agents Antifungal Agents Biological Assay Blood - brain barrier anatomy Cell Wall Cells Chemistry Clinical Collection Cryptococcal Meningitis Cryptococcus neoformans Cryptococcus neoformans infection Data Death Rate Development Drug Combinations Evaluation Fluconazole Flucytosine Funding Goals Gold HIV Human Human Cell Line In Vitro Industrial fungicide Institutes Laboratories Lethal Dose 50 Libraries Medical Meningoencephalitis Molecular Bank Molecular Probes Molecular Target Nature New Agents Opportunistic Infections Oral Outcome Pathway interactions Patients Persons Pharmaceutical Chemistry Pharmaceutical Preparations Pharmacology Prevalence Process Regimen Research Infrastructure Resources Signal Transduction Squalene Synthetase Structure Structure-Activity Relationship Testing Thiourea Toxic effect Tuberculosis United States National Institutes of Health Validation adenylate kinase base benzimidazole burden of illness chemical genetics design drug candidate effective therapy epidemiology study experimental study genetic approach genomic profiles global health high throughput screening improved inhibitor/antagonist killings mutant novel novel therapeutics pathogen preclinical development programs public health relevance scaffold screening small molecule

项目摘要

DESCRIPTION (provided by applicant): Cryptococcal meningitis is one of the most important opportunistic infections affecting people living with HIV/AIDS. Recent epidemiologic studies indicate that approximately 1 million new cases occur each year and over 700,000 people die each year; in sub-Saharan Africa, more HIV patients die of cryptococcal meningitis each year than tuberculosis. The gold standard therapy for cryptococcosis is amphotericin B combined with 5-flucytosine. Although this regimen is easily administered in resource-rich regions of the world, it is not available in many resource-limited regions with the highest burden of disease. In these regions, fluconazole, a less effective, fungistatic agent, is used because it is readily available, safe, and administered orally. Unfortunately, patients treated with FLU have much higher death rates; this has been attributed to the fungistatic activity of FLU. Thus, new therapies for cryptococcosis are urgently needed and this is the long-term goal of our project. Because molecules with fungicidal activity are clinically superior to fungistatic drugs, we have developed a high throughput screening assay that directly identifies molecules with fungicidal activity toward C. neoformans. We have screened two distinct libraries with the assay: 1) a 350,000 compound library through an NIH-funded Molecular Probes and Library Screening Network project and 2) a focused set of 700 molecules from Merck Laboratories collection of anti-candidal molecules. The former screen was designed to identify a molecule with activity against cell wall related processes in C. neoformans: a novel benzimidazole thiourea scaffold with low human toxicity and good anti-cryptococcal activity emerged from this screen. We will identify its mechanism of action in Aim 1 to set the stage for subsequent optimization of its anti-cryptococcal activity. From the Merck Library, we have identified 22 molecules with fungicidal activity against C. neoformans at concentrations ≤ 2 µg/mL. We will complete the secondary screening of the set of Merck library hits in Aim 2 and identify the mechanism of action for a tota of four high priority scaffolds. Initial evaluation indicates that a set of squalene synthase inhibitors are among the hits. We will test that hypothesis and identify the target of three high priority scaffolds from the remaining hits. The mechanistic information that emerges from this exploratory project will be used as a basis for a subsequent application to optimize the anti-cryptococcal activity of the scaffolds.

描述（由适用提供）：隐球菌脑膜炎是影响艾滋病毒/艾滋病患者的最重要的机会感染之一。最近的流行病学研究表明，每年大约有100万例新病例，每年有70万人死亡；在撒哈拉以南非洲，比结核病多的HIV患者每年死于隐球菌脑膜炎。隐球菌的黄金标准疗法是两性霉素B与5-荧光蛋白酶结合。尽管该方案很容易在世界上资源丰富的地区进行，但在许多资源有限的地区没有疾病负担最高的地区。在这些区域中，使用氟康唑，一种效率较低的拟合剂，是因为它容易获得，安全和口服。不幸的是，接受流感治疗的患者死亡率更高。这归因于流感的真实活性。因此，迫切需要新的隐球菌病疗法，这是我们项目的长期目标。由于具有杀真菌活性的分子在临床上优于真菌药物，因此我们开发了一种高吞吐量筛选测定法，该测定法直接鉴定出具有杀真菌活性的分子对新生梭菌。我们已经通过NIH资助的分子探针和图书馆筛选网络项目筛选了两个不同的文库：1）350,000个化合物库，以及2）从默克实验室收集的抗狂欢分子收集的一组重点的700个分子。以前的屏幕旨在鉴定出具有对细胞壁相关过程的活性的分子：新型的苯咪唑硫脲支架具有低人类毒性和良好的抗晶体活性。我们将在目标1中确定其作用机理，以为随后优化其抗晶体活性奠定阶段。从默克文库中，我们以浓度≤2µg/ml的菌C. neoformans确定了22个具有杀真菌活性的分子。我们将完成对AIM 2中默克库命中的辅助筛选，并确定四个高优先级支架的TOTA的作用机理。初始评估表明一组尖甲烯合酶抑制剂是其中的一部分。我们将检验该假设，并确定其余命中的三个高优先级支架的目标。从这个探索项目中出现的机械信息将被用作后续应用的基础，以优化脚手架的抗晶体活性。