Mohan K, Dubey M L, Ganguly N K, Nain C K, Mahajan R C
Department of Parasitology, Postgraduate Institute of Medical Education & Research, Chandigarh, India.
Indian J Biochem Biophys. 1994 Dec;31(6):476-9.
In an attempt to understand the pathogenesis of anaemia in Plasmodium falciparum infection, the status of erythrocyte glutathione and vitamin E content in relation to the susceptibility of infected red cells to peroxide haemolysis was examined. Synchronized cultures of the parasite with either ring-, trophozoite or schizont-infected red cells showed a gradual increase in the reduced glutathione content which was significantly higher (p < 0.05) in schizont-infected cells. Trophozoite-infected cells revealed significant increase in oxidized glutathione (p < 0.01) suggesting an increase in glutathione utilization during active erythrocytic schizogony of the parasites. The membrane antioxidant vitamin E also showed an increased accumulation in trophozoite- and schizont-infected red cells (p < 0.05) but not in the uninfected or ring-infected erythrocytes. Despite a favourable change in these antioxidants, the infected as well as uninfected red cells from parasite cultures showed enhanced peroxide haemolysis (uninfected, p < 0.05; ring-rich, p < 0.05, trophozoite- and schizont-rich, p < 0.001). The study provided direct evidence for enhanced susceptibility of red cells to lysis, including those of uninfected cells exposed to parasite products. This might explain the cause for much higher red cell loss and anaemia during P. falciparum infection than all the infected cells put together.
为了了解恶性疟原虫感染中贫血的发病机制，研究了红细胞谷胱甘肽和维生素E含量与感染红细胞对过氧化物溶血易感性之间的关系。用环状体、滋养体或裂殖体感染红细胞的疟原虫同步培养物显示，还原型谷胱甘肽含量逐渐增加，在裂殖体感染的细胞中显著更高（p<0.05）。滋养体感染的细胞显示氧化型谷胱甘肽显著增加（p<0.01），这表明在疟原虫活跃的红细胞内裂体增殖过程中谷胱甘肽利用率增加。膜抗氧化剂维生素E在滋养体和裂殖体感染的红细胞中也显示出积累增加（p<0.05），但在未感染或环状体感染的红细胞中没有增加。尽管这些抗氧化剂有有利变化，但来自疟原虫培养物的感染和未感染红细胞均显示出过氧化物溶血增强（未感染的，p<0.05；富含环状体的，p<0.05，富含滋养体和裂殖体的，p<0.001）。该研究为红细胞对裂解的易感性增强提供了直接证据，包括暴露于疟原虫产物的未感染细胞。这可能解释了恶性疟原虫感染期间红细胞损失和贫血比所有感染细胞总和高得多的原因。
