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.
ABSTRACT
ObjectiveTo investigate the protective effect of Geju Hugan tablets on the liver of mice with alcohol-induced liver injury， and explore the underlying mechanism based on nuclear factor-κB p65 （NF-κB p65） and B-cell lymphoma-2 （Bcl-2）/Bcl-2-associated X protein （Bax） signaling pathways. MethodAccording to the body weight， 60 SPF-grade male ICR mice were randomized into normal， model， Compound Yiganling tablets （0.16 g·kg-1）， and low-， medium-， and high-dose （0.2， 0.4， 0.8 g·kg-1， respectively） Geju Hugan tablets groups. The drugs were administrated at the corresponding doses by gavage， and the normal and model groups with equal volume of pure water once a day for 28 consecutive days. On day 29， the mice in other groups except the normal group were administrated with liquor （53% Vol） by gavage twice a day at the doses of 20， 10 mL·kg-1 and with the interval of 6 h. Samples were harvested on day 30. The histopathological changes in the liver were observed by hematoxylin-eosin （HE） staining， and the ultrastructural changes in hepatocytes were observed by transmission electron microscopy. The enzyme-linked immunosorbent assay was employed to measure the levels of malonaldehyde （MDA）， reduced glutathione （GSH）， and triglycerides （TG） in the liver tissue and the levels of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） in the serum. Western blotting was employed to determine the protein levels of NF-κB p65， phosphorylated p-inhibitor kappa B alpha （p-IκBα）， Bcl-2， and Bax in the liver tissue. ResultCompared with the normal group， the model group showed increases in the ALT， AST， MDA， and TG levels， a decrease in the GSH level， and increases in the liver injury scores evaluated based on the HE， oil red O， and transmission electron microscopy （P<0.01）. Moreover， the model group showed up-regulated expression of NF-κB， p-IκBα， and Bax （P<0.05， P<0.01） and down-regulated expression of Bcl-2 （P<0.05） in the liver tissue. Compared with the model group， Geju Hugan tablets of all the doses lowered the ALT， AST， MDA， and TG levels and elevated the GSH level （P<0.01）. The liver injury scores assessed based on HE staining and transmission electron microscopy in the medium- and high-dose Geju Hugan tablets groups were lower than those in the model group （P<0.01）. Compared with the model group， medium- and high-dose Geju Hugan tablets down-regulated the protein levels of NF-κB， p-IκBα， and Bax （P<0.01） and all doses of Geju Hugan tablets up-regulated the protein level of Bcl-2 （P<0.01）. ConclusionGeju Hugan tablets protect mice from alcohol-induced liver injury by down-regulating NF-κB signaling pathway to alleviate inflammation in the liver tissue and down-regulating the expression of Bax and up-regulating the expression of Bcl-2 to inhibit hepatocyte apoptosis.