Abstract
1- Introduction
2- Drug resistance in parasites
3- ATP-binding cassette (ABC) transporters in parasites
4- Conclusion
References
Abstract
Nowadays, drug resistance in parasites is considered to be one of the foremost concerns in health and disease management. It is interconnected worldwide and undermines the health of millions of people, threatening to grow worse. Unfortunately, it does not receive serious attention from every corner of society. Consequently, drug resistance in parasites is gradually complicating and challenging the treatment of parasitic diseases. In this context, we have dedicated ourselves to review the incidence of drug resistance in the protozoan parasites Plasmodium, Leishmania, Trypanosoma, Entamoeba and Toxoplasma gondii. Moreover, understanding the role of ATP-binding cassette (ABC) transporters in drug resistance is essential in the control of parasitic diseases. Therefore, we also focused on the involvement of ABC transporters in drug resistance, which will be a superior approach to find ways for better regulation of diseases caused by parasitic infections.
Drug resistance in parasites
Due to lack of effective vaccines, chemotherapy remains the mainstay of defence against parasites responsible for a wide spectrum of diseases in humans. Unfortunately, resistance has developed in the respective parasites for the majority of clinically used drugs against these diseases. Drug resistance mechanisms in parasites are very inconsistent in terms of the nature and life cycle of parasites [7]. In general, mechanisms of drug resistance in pathogenic parasites depend on a variety of mechanisms consisting of augmented drug efflux, reduced drug uptake, mutation events in targeted enzymes, metabolic upregulation, and deficiency of the target sites for antiparasitic drugs, etc. Apart from these issues, various genetic mechanisms including gene deletions, gene mutations and, most importantly, chimerisation of genes also play a crucial role in drug resistance mechanisms [8]. Incidentally, the formation of chimeric genes in drug resistance is not yet well established in all pathogenic parasites; to the best of our knowledge from a literature search, it is greatly studied in Trypanosoma compared with other parasites. However, in some parasites resistance appears through many other unknown mechanisms and resistance to most antiparasitic drugs in the majority of parasites is now widespread. The following sections of this review article discuss the drug resistance of the protozoan parasites Plasmodium, Leishmania, Trypanosoma, Entamoeba and T. gondii.