Ibraheem Zaid O, Abd Majid R, Noor S Mohd, Sedik H Mohd, Basir R
Pharmacology Unit, Department of Human Anatomy, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Malar Res Treat. 2014;2014:950424. doi: 10.1155/2014/950424. Epub 2014 Nov 11.
Emergence of drugs resistant strains of Plasmodium falciparum has augmented the scourge of malaria in endemic areas. Antimalaria drugs act on different intracellular targets. The majority of them interfere with digestive vacuoles (DVs) while others affect other organelles, namely, apicoplast and mitochondria. Prevention of drug accumulation or access into the target site is one of the mechanisms that plasmodium adopts to develop resistance. Plasmodia are endowed with series of transporters that shuffle drugs away from the target site, namely, pfmdr (Plasmodium falciparum multidrug resistance transporter) and pfcrt (Plasmodium falciparum chloroquine resistance transporter) which exist in DV membrane and are considered as putative markers of CQ resistance. They are homologues to human P-glycoproteins (P-gh or multidrug resistance system) and members of drug metabolite transporter (DMT) family, respectively. The former mediates drifting of xenobiotics towards the DV while the latter chucks them outside. Resistance to drugs whose target site of action is intravacuolar develops when the transporters expel them outside the DVs and vice versa for those whose target is extravacuolar. In this review, we are going to summarize the possible pfcrt and pfmdr mutation and their role in changing plasmodium sensitivity to different anti-Plasmodium drugs.
恶性疟原虫耐药菌株的出现加剧了疟疾在流行地区的肆虐。抗疟药物作用于不同的细胞内靶点。其中大多数干扰消化液泡(DVs),而其他药物则影响其他细胞器,即质体和线粒体。防止药物积累或进入靶点是疟原虫产生耐药性的机制之一。疟原虫拥有一系列转运蛋白,可将药物从靶点转运走,即存在于DV膜中的恶性疟原虫多药耐药转运蛋白(pfmdr)和恶性疟原虫氯喹耐药转运蛋白(pfcrt),它们被认为是氯喹耐药性的推定标志物。它们分别与人P-糖蛋白(P-gh或多药耐药系统)和药物代谢物转运蛋白(DMT)家族成员同源。前者介导异生物质向DV的转运,而后者将它们排出细胞外。当转运蛋白将作用靶点位于液泡内的药物排出DV之外时,就会对这些药物产生耐药性,反之,对于作用靶点位于液泡外的药物则相反。在这篇综述中,我们将总结pfcrt和pfmdr可能的突变及其在改变疟原虫对不同抗疟药物敏感性方面的作用。