Differential Analysis of Erythrocyte Flexibility of PbK173 Artemisinin-sensitive Strains / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo detect the flexibility differences of Plasmodium berghei K173 （PbK173）-infected red blood cells with varying degrees of sensitivity to artemisinin-based drugs and to preliminarily explore the underlying mechanisms of the differences. MethodA total of 102 specific-pathogen-free （SPF） male C57BL/6 mice were randomly divided into three groups， with 30 mice each in the control group and PbK173-resistant （PbK173-R） group， and 42 mice in the PbK173-sensitive （PbK173-S） group. Except for the control group， the rest groups were vaccinated with 1×107 PbK173-S/PbK173-R infected red blood cells to establish a mouse malaria model. During the administration and recovery periods （control group， PbK173-R/PbK173-S）， dihydroartemisinin （DHA， 40 mg·kg-1） and malaridine （MD， 6 mg·kg-1） were administered continuously for four days. Peripheral blood was taken from the PbK173-S/PbK173-R groups with an infection rate equal to or greater than 20%. Peripheral blood and each organ were taken on the first day at the end of administration （dosing period） and on the fifth day at the end of administration （recovery period）， and blood parameters and organ indices of each group were examined. The osmotic fragility of peripheral blood red blood cells in each group was detected using the red blood cell osmotic fragility test. Western blot was applied to determine the levels of Piezo1 and Band3 proteins in the red blood cell membrane. ResultDuring the administration and recovery periods， there were no significant differences between the PbK173-S MD group and the DHA group. During the administration period， there were no significant differences in hematological parameters between PbK173-S and PbK173-R in the MD group. However， during the recovery period， the red blood cell count， hemoglobin concentration and hematocrit of the PbK173-R group were significantly higher than those of the PbK173-S group （P<0.05） in the MD group. Compared with that of the control group， the osmotic fragility of the PbK173-S/PbK173-R groups was significantly enhanced （P<0.01）， and the osmotic fragility of the PbK173-S group was significantly stronger than that of the PbK173-R group （P<0.01）. The osmotic fragility of red blood cells in the PbK173-S group during the administration period was significantly stronger than that in the control group and PbK173-R group during the administration period （P<0.01）. The osmotic fragility of red blood cells in the PbK173-R group during the recovery period was significantly higher than that in the control group during the administration period and the PbK173-S group during the recovery period （P<0.05）. Compared with those in the control group， the Piezo1 protein and Band3 protein in the red blood cell membrane of the PbK173-S group were significantly reduced （P<0.01）. Compared with those in the PbK173-R group， the Piezo1 protein and Band 3 protein in the red blood cell membrane of the PbK173-S group were significantly reduced. ConclusionThe flexibility of PbK173-infected red blood cells with different sensitivities to artemisinins differed. Plasmodium-infected red blood cells significantly reduced the levels of Piezo1 and Band3 proteins in the red blood cell membrane， and the erythrocyte flexibility exhibited a decreasing trend in the following order： normal group， PbK173-R group， and PbK173-S group.