Department of Physiology, University of Tübingen, Gmelinstrasse 5, D-72076 Tübingen, Germany.
Acta Trop. 2010 Oct;116(1):39-44. doi: 10.1016/j.actatropica.2010.05.005. Epub 2010 May 27.
According to previous observations, amiodarone triggers suicidal erythrocyte death or eryptosis, which is characterized by cell shrinkage and exposure of phosphatidylserine at the erythrocyte surface. Eryptosis may in turn accelerate the clearance of Plasmodium-infected erythrocytes. The present study tested whether amiodarone augments phosphatidylserine exposure of Plasmodium-infected erythrocytes, interferes with the development of parasitemia and thus influences the course of malaria. The in vitro infection of human erythrocytes with Plasmodium falciparum (strain BinH) increased annexin V-binding, an effect significantly augmented by amiodarone (10 microM). Amiodarone further significantly decreased intraerythrocytic DNA/RNA content (> or =5 microM) and in vitro parasitemia (> or =1 microM). Following infection of mice with Plasmodiumberghei ANKA by intraperitoneal injection of parasitized murine erythrocytes (1x10(6)) amiodarone (intraperitoneal 50mg/kg b.w.) significantly decreased the parasitemia and increased the survival of P. berghei-infected mice (from 0% to 70% 26 days after infection). Moreover, treatment with amiodarone significantly increased the percentage of PS-exposing infected erythrocytes. In conclusion, amiodarone inhibits intraerythrocytic growth of P. falciparum, enhances suicidal death of infected erythrocytes, decreases parasitemia following P. berghei infection and supports host survival during malaria.
根据以往的观察,胺碘酮会引发自杀性红细胞死亡或红细胞溶血,其特征是细胞收缩和红细胞表面磷脂酰丝氨酸的暴露。红细胞溶血反过来可能加速疟原虫感染的红细胞清除。本研究检测了胺碘酮是否增强了疟原虫感染的红细胞中磷脂酰丝氨酸的暴露,是否干扰了寄生虫血症的发展,从而影响疟疾的病程。用疟原虫恶性疟(BinH 株)体外感染人红细胞,增加了 annexin V 结合,胺碘酮(10 μM)显著增强了这种作用。胺碘酮还显著降低了红细胞内 DNA/RNA 含量(≥5 μM)和体外寄生虫血症(≥1 μM)。用感染疟原虫伯氏疟原虫 ANKA 的小鼠通过腹腔内注射寄生的鼠红细胞(1x10(6))进行感染,胺碘酮(腹腔内 50mg/kg b.w.)显著降低了寄生虫血症并增加了感染疟原虫伯氏疟原虫的小鼠的存活率(从感染后 26 天的 0%增加到 70%)。此外,用胺碘酮治疗显著增加了 PS 暴露的感染红细胞的百分比。总之,胺碘酮抑制恶性疟原虫在红细胞内的生长,增强感染红细胞的自杀性死亡,降低伯氏疟原虫感染后的寄生虫血症,并支持疟疾期间宿主的存活。