Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America.
Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America.
PLoS Negl Trop Dis. 2020 Sep 24;14(9):e0008353. doi: 10.1371/journal.pntd.0008353. eCollection 2020 Sep.
Diseases caused by pathogenic free-living amoebae include primary amoebic meningoencephalitis (Naegleria fowleri), granulomatous amoebic encephalitis (Acanthamoeba spp.), Acanthamoeba keratitis, and Balamuthia amoebic encephalitis (Balamuthia mandrillaris). Each of these are difficult to treat and have high morbidity and mortality rates due to lack of effective therapeutics. Since repurposing drugs is an ideal strategy for orphan diseases, we conducted a high throughput phenotypic screen of 12,000 compounds from the Calibr ReFRAME library. We discovered a total of 58 potent inhibitors (IC50 <1 μM) against N. fowleri (n = 19), A. castellanii (n = 12), and B. mandrillaris (n = 27) plus an additional 90 micromolar inhibitors. Of these, 113 inhibitors have never been reported to have activity against Naegleria, Acanthamoeba or Balamuthia. Rapid onset of action is important for new anti-amoeba drugs and we identified 19 compounds that inhibit N. fowleri in vitro within 24 hours (halofuginone, NVP-HSP990, fumagillin, bardoxolone, belaronib, and BPH-942, solithromycin, nitracrine, quisinostat, pabinostat, pracinostat, dacinostat, fimepinostat, sanguinarium, radicicol, acriflavine, REP3132, BC-3205 and PF-4287881). These compounds inhibit N. fowleri in vitro faster than any of the drugs currently used for chemotherapy. The results of these studies demonstrate the utility of phenotypic screens for discovery of new drugs for pathogenic free-living amoebae, including Acanthamoeba for the first time. Given that many of the repurposed drugs have known mechanisms of action, these compounds can be used to validate new targets for structure-based drug design.
由致病自由生活阿米巴引起的疾病包括原发性阿米巴脑膜脑炎（福氏耐格里阿米巴）、肉芽肿性阿米巴脑炎（棘阿米巴属）、棘阿米巴角膜炎和巴尔通体阿米巴脑炎（巴尔通体曼氏亚种）。由于缺乏有效的治疗方法，这些疾病都难以治疗，且发病率和死亡率都很高。由于重新利用药物是治疗孤儿病的理想策略，我们对 Calibr ReFRAME 文库中的 12000 种化合物进行了高通量表型筛选。我们总共发现了 58 种对福氏耐格里阿米巴（n = 19）、棘阿米巴属（n = 12）和巴尔通体曼氏亚种（n = 27）具有抑制活性的有效化合物（IC50 <1 μM），另外还有 90 种化合物的抑制率在微摩尔级别。其中，有 113 种抑制剂从未被报道过对纳格里虫、棘阿米巴属或巴尔通体具有活性。对于新的抗阿米巴药物，快速起效非常重要，我们鉴定了 19 种能够在 24 小时内抑制福氏耐格里阿米巴的化合物（卤夫酮、NVP-HSP990、灭滴灵、巴多昔芬、贝拉龙尼、BPH-942、索利霉素、硝卡腙、奎那司他、帕比司他、普拉西诺肽、达西诺肽、菲米诺肽、血根碱、雷地昔醇、吖啶黄、REP3132、BC-3205 和 PF-4287881）。这些化合物在体外抑制福氏耐格里阿米巴的速度比目前用于化疗的任何药物都要快。这些研究结果表明，表型筛选对于发现新的致病性自由生活阿米巴药物是有用的，这是首次针对棘阿米巴属的筛选。鉴于许多重新利用的药物具有已知的作用机制，这些化合物可用于验证基于结构的药物设计的新靶点。
