The pathogenic free-living amoeba, Acanthamoeba castellanii, is responsible for a rare but deadly central nervous system infection, granulomatous amoebic encephalitis and a blinding eye disease called Acanthamoeba keratitis. Currently, a combination of biguanides, amidine, azoles and antibiotics are used to manage these infections; however, the host cell cytotoxicity of these drugs remains a challenge. Furthermore, Acanthamoeba species are capable of transforming to the cyst form to resist chemotherapy. Herein, we have developed a nano drug delivery system based on iron oxide nanoparticles conjugated with isoniazid, which were further loaded with amphotericin B (ISO-NPs-AMP) to cause potent antiamoebic effects against Acanthamoeba castellanii. The IC₅₀ of isoniazid conjugated with magnetic nanoparticles and loaded with amphotericin B was found to be 45 μg/mL against Acanthamoeba castellanii trophozoites and 50 μg/mL against cysts. The results obtained in this study have promising implications in drug discovery as these nanomaterials exhibited high trophicidal and cysticidal effects, as well as limited cytotoxicity against rat and human cells.

中文翻译：

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载有两性霉素B的异烟肼共轭磁性纳米颗粒，可有效对抗卡氏棘阿米巴虫。

致病性的自由生存变形虫阿米巴虫（Acanthamoeba castellanii）是罕见但致命的中枢神经系统感染，肉芽肿性阿米巴脑炎和致盲性眼病，称为阿米巴虫角膜炎。目前，使用双胍、,、唑和抗生素的组合来控制这些感染。然而，这些药物对宿主细胞的细胞毒性仍然是一个挑战。此外，棘阿米巴菌种能够转化为囊肿形式以抵抗化学疗法。本文中，我们开发了一种基于与异烟肼共轭的氧化铁纳米粒子的纳米药物递送系统，该纳米粒子进一步负载了两性霉素B（ISO-NPs-AMP），从而对卡氏棘阿米巴产生了有效的抗贫血作用。异烟肼与磁性纳米颗粒偶联并负载了两性霉素B的IC ₅₀被发现对棘孢棘孢营养体为45μg/ mL，对囊肿为50μg/ mL。这项研究中获得的结果在药物开发中具有可喜的意义，因为这些纳米材料显示出高杀菌和杀囊作用，并且对大鼠和人类细胞的细胞毒性有限。