Moon Eun-Kyung, Choi Hyun-Seo, Kong Hyun-Hee, Quan Fu-Shi
Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul, 02447, Republic of Korea.
Department of Parasitology, Dong-A University College of Medicine, Busan, 49201, Republic of Korea.
Exp Parasitol. 2018 Aug;191:31-35. doi: 10.1016/j.exppara.2018.06.002. Epub 2018 Jun 6.
Several chemotherapeutic drugs have been described as amoebicidal agents acting against Acanthamoeba trophozoites and cysts. However, the underlying mechanism of action is poorly characterized. Here, we describe programmed cell death (PCD) in A. castellanii induced by polyhexamethylene biguanide (PHMB) and chloroquine. We used four types of amoebicidal agents including 0.02% PHMB, 0.02% chlorhexidine digluconate, 100 μM chloroquine, and 100 μM 2,6-dichlorobenzonitrile to kill Acanthamoeba trophozoites and cysts. Exposure to PHMB and chloroquine induced cell shrinkage and membrane blebbing in Acanthamoeba, observed microscopically. Externalization of phosphatidyl serine on the membranes of Acanthamoeba was detected by annexin V staining. Apoptotic cell death of Acanthamoeba by PHMB and chloroquine was confirmed by FACS analysis. Nuclear fragmentation of Acanthamoeba was demonstrated by DAPI staining. PHMB induced PCD in trophozoites and cysts, and chloroquine induced PCD in cysts. These findings are discussed to establish the most effective treatment for Acanthamoeba-induced keratitis.
几种化疗药物已被描述为对棘阿米巴滋养体和包囊具有杀阿米巴作用的药物。然而，其潜在的作用机制仍不清楚。在此，我们描述了聚六亚甲基双胍（PHMB）和氯喹诱导的卡氏棘阿米巴程序性细胞死亡（PCD）。我们使用了四种杀阿米巴药物，包括0.02%的PHMB、0.02%的葡萄糖酸氯己定、100μM的氯喹和100μM的2,6-二氯苯腈来杀死棘阿米巴滋养体和包囊。显微镜观察发现，暴露于PHMB和氯喹会导致棘阿米巴细胞收缩和膜泡形成。通过膜联蛋白V染色检测到棘阿米巴细胞膜上磷脂酰丝氨酸的外化。通过流式细胞术分析证实了PHMB和氯喹诱导的棘阿米巴细胞凋亡性死亡。通过DAPI染色证明了棘阿米巴的核碎裂。PHMB诱导滋养体和包囊发生PCD，氯喹诱导包囊发生PCD。讨论了这些发现，以确定治疗棘阿米巴性角膜炎的最有效方法。
