Plasmodium falciparum
- Mechanisms of ResistanceAtypical Molecular Basis for Drug Resistance to Mitochondrial Function Inhibitors in Plasmodium falciparum
The continued emergence of drug-resistant Plasmodium falciparum parasites hinders global attempts to eradicate malaria, emphasizing the need to identify new antimalarial drugs. Attractive targets for chemotherapeutic intervention are the cytochrome (cyt) bc1 complex, which is an essential component of the mitochondrial electron transport chain (...
- Mechanisms of ResistanceSelection of Cytochrome b Mutants Is Rare among Plasmodium falciparum Patients Failing Treatment with Atovaquone-Proguanil in Cambodia
Atovaquone-proguanil remains effective against multidrug-resistant Plasmodium falciparum in Southeast Asia, but resistance is mediated by a single point mutation in cytochrome b (cytb) that can arise during treatment. Among 14 atovaquone-proguanil treatment failures in a clinical trial in Cambodia, only one recrudescence harbored the cytb...
- Clinical TherapeuticsDefining the Antimalarial Activity of Cipargamin in Healthy Volunteers Experimentally Infected with Blood-Stage Plasmodium falciparum
The spiroindolone cipargamin, a new antimalarial compound that inhibits Plasmodium ATP4, is currently in clinical development. This study aimed to characterize the antimalarial activity of cipargamin in healthy volunteers experimentally infected with blood-stage Plasmodium falciparum.
- PharmacologyIn Vivo Efficacy and Metabolism of the Antimalarial Cycleanine and Improved In Vitro Antiplasmodial Activity of Semisynthetic Analogues
Bisbenzylisoquinoline (BBIQ) alkaloids are a diverse group of natural products that demonstrate a range of biological activities. In this study, the in vitro antiplasmodial activity of three BBIQ alkaloids (cycleanine [compound 1], isochondodendrine [compound 2], and 2′-norcocsuline [compound 3]) isolated from the Triclisia subcordata Oliv. medicinal plant...
- Mechanisms of ResistanceTransmission of Artemisinin-Resistant Malaria Parasites to Mosquitoes under Antimalarial Drug Pressure
Resistance to artemisinin-based combination therapy (ACT) in the Plasmodium falciparum parasite is threatening to reverse recent gains in reducing global deaths from malaria. While resistance manifests as delayed parasite clearance in patients, the phenotype can only spread geographically via the sexual stages and mosquito transmission. In addition to their asexual...
- Chemistry; BiosynthesisRegioisomerization of Antimalarial Drug WR99210 Explains the Inactivity of a Commercial Stock
WR99210, a former antimalarial drug candidate now widely used for the selection of Plasmodium transfectants, selectively targets the parasite’s dihydrofolate reductase thymidine synthase bifunctional enzyme (DHFR-TS) but not human DHFR, which is not fused with TS. Accordingly, WR99210 and plasmids expressing the human dhfr gene have become valued tools for the genetic modification of parasites in the laboratory....
- Mechanisms of Action: Physiological EffectsInhibition of PfMYST Histone Acetyltransferase Activity Blocks Plasmodium falciparum Growth and Survival
One of the major barriers in the prevention and control of malaria programs worldwide is the growing emergence of multidrug resistance in Plasmodium parasites, and this necessitates continued efforts to discover and develop effective drug molecules targeting novel proteins essential for parasite survival. In recent years, epigenetic regulators have evolved as an attractive drug target option owing to their crucial role in...
- SusceptibilityTolerance of Gambian Plasmodium falciparum to Dihydroartemisinin and Lumefantrine Detected by Ex Vivo Parasite Survival Rate Assay
Monitoring of Plasmodium falciparum sensitivity to antimalarial drugs in Africa is vital for malaria elimination. However, the commonly used ex vivo/in vitro 50% inhibitory concentration (IC50) test gives inconsistent results for several antimalarials, while the alternative ring-stage survival assay (RSA) for artemisinin derivatives has...
- Mechanisms of ResistanceAssociations between Malaria-Preventive Regimens and Plasmodium falciparum Drug Resistance-Mediating Polymorphisms in Ugandan Pregnant Women
Intermittent preventive treatment in pregnancy (IPTp) with monthly sulfadoxine-pyrimethamine (SP) is recommended for malaria-endemic parts of Africa, but efficacy is compromised by resistance, and, in recent trials, dihydroartemisinin-piperaquine (DP) has shown better antimalarial protective efficacy. We utilized blood samples from a recent trial to evaluate selection by IPTp with DP or SP of...
- Epidemiology and SurveillancePrevalence of Plasmodium falciparum Kelch 13 (PfK13) and Ubiquitin-Specific Protease 1 (pfubp1) Gene Polymorphisms in Returning Travelers from Africa Reported in Eastern China
Delayed clearance of Plasmodium falciparum by artemisinin-based combination therapies (ACTs) has already been observed for African isolates. Here, we aimed to investigate the prevalence, among travelers returning from African countries, of polymorphisms in two genes correlated with delayed parasite clearance (encoding...