Inhibitory Mechanisms of DHA/CQ on pH and Iron Homeostasis of Erythrocytic Stage Growth of Plasmodium falciparum
Inhibitory Mechanisms of DHA/CQ on pH and Iron Homeostasis of Erythrocytic Stage Growth of Plasmodium falciparum
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DOI：
10.3390/molecules24101941
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发表时间：
2019-05-02
期刊：
影响因子：
4.6
通讯作者：
Li, Canghai
中科院分区：
文献类型：
--
作者：
Tang, Tian;Xu, Wenhui;Li, Canghai
疟疾是由疟原虫群引起的传染病。抗疟药物 DHA/CQ 的作用机制至今仍不清楚。研究了DHA/CQ或V-ATPase抑制剂Baf-A1单独处理或DHA/CQ与Baf-A1联合处理对恶性疟原虫菌株3D7生长的抑制作用(IC50)。用pH探针BCECF，AM和铁探针钙黄绿素，AM标记细胞内的细胞质pH和不稳定铁库（LIP），通过FCM测量探针的荧光。通过 RT-qPCR 测试低剂量 DHA（0.2 nM、0.4 nM、0.8 nM）对位于 DV 膜上的 V-ATP 酶（vapE、vapA、vapG）基因表达的影响。 DHA与Baf-A1联合在IC50浓度下对寄生虫生长表现出协同作用(CI = 0.524)。不同剂量的DHA/Baf-A1对细胞内pH和铁有显着影响。 CQ与Baf-A1联用以IC50浓度降低细胞内pH。 DHA与Baf-A1联合以20 IC50的浓度增加细胞内LIP。所有低剂量 DHA (0.2/0.4/0.8 nM) 均显着下调 vapA 基因表达 (p < 0.001)，0.8 nM DHA 显着上调 vapG/vapE 表达 (p < 0.001)。与亚铁相互作用，影响 DV 膜质子泵和酸性 pH 或细胞质铁稳态可能是 DHA 的抗疟机制，而 CQ 在体外显示出对寄生虫细胞质 pH 的影响。最后，本文为我们提供了抗疟药物组合和新的潜在抗疟联合疗法的初步结果和新思路。
Malaria is an infectious disease caused by Plasmodium group. The mechanisms of antimalarial drugs DHA/CQ are still unclear today. The inhibitory effects (IC50) of single treatments with DHA/CQ or V-ATPase inhibitor Baf-A1 or combination treatments by DHA/CQ combined with Baf-A1 on the growth of Plasmodium falciparum strain 3D7 was investigated. Intracellular cytoplasmic pH and labile iron pool (LIP) were labeled by pH probe BCECF, AM and iron probe calcein, AM, the fluorescence of the probes was measured by FCM. The effects of low doses of DHA (0.2 nM, 0.4 nM, 0.8 nM) on gene expression of V-ATPases (vapE, vapA, vapG) located in the membrane of DV were tested by RT-qPCR. DHA combined with Baf-A1 showed a synergism effect (CI = 0.524) on the parasite growth in the concentration of IC50. Intracellular pH and irons were effected significantly by different doses of DHA/Baf-A1. Intracellular pH was decreased by CQ combined with Baf-A1 in the concentration of IC50. Intracellular LIP was increased by DHA combined with Baf-A1 in the concentration of 20 IC50. The expression of gene vapA was down-regulated by all low doses of DHA (0.2/0.4/0.8 nM) significantly (p < 0.001) and the expression of vapG/vapE were up-regulated by 0.8 nM DHA significantly (p < 0.001). Interacting with ferrous irons, affecting the DV membrane proton pumping and acidic pH or cytoplasmic irons homeostasis may be the antimalarial mechanism of DHA while CQ showed an effect on cytoplasmic pH of parasite in vitro. Lastly, this article provides us preliminary results and a new idea for antimalarial drugs combination and new potential antimalarial combination therapies.