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Najmi, A. K.

Publications and source records attributed to Najmi, A. K..

2 recordsLinked to original sources

Selective targeting of Plasmodium falciparum hexose transporter by phytochemical Ginsenoside Rg1 disrupts glucose metabolism and block development of parasite

The emergence of resistance to first-line antimalarial therapies highlights the critical need for next-generation drugs that target distinct molecular pathways and employ novel mechanisms of action. Notably, the intra-erythrocytic parasite development is highly dependent on a sustained glucose supply as their fundamental energy source. Therefore, exploiting a "selective starvation" strategy, by targeting the parasites reliance on glucose metabolism, particularly through the Plasmodium falciparum hexose transporter (PfHT1), which is critical for parasite survival can serve as a promising therapeutic approach to combat multidrug-resistant Plasmodium parasites. Through molecular docking and structure-based drug design approach, we identified a natural compound, Ginsenoside Rg1 (G-Rg1) from drug bank database library, as a potential PfHT1 inhibitor. The PfHT1 specificity of G-Rg1 was validated using yeast complementation model. Subsequently, to investigate the role of PfHT1 in drug resistant Pf parasites we investigated the stage-specific expression of PfHT1 in both artemisinin (ART)-sensitive and resistant Pf parasites and reported its elevated expression in resistant parasites, predicting its role in their survival. Notably, in vitro growth inhibition studies demonstrated that G-Rg1 effectively suppressed the growth of both ART-sensitive and resistant Pf parasites. Additionally, G-Rg1 potentiated the efficacy of dihydroartemisinin in combination and ring survival assays, indicating its potential to circumvent resistance mechanisms. G-Rg1 administration alone and in combination with ART, in P. berghei ANKA-infected mice reduced parasite multiplication and increased mean survival time. Our findings support G-Rg1 as a promising candidate for drug development against malaria, highlighting the potential of targeting PfHT1 to combat drug-resistant malaria.

pharmacology and toxicology↗

Tackling emerging artemisinin resistance by modulating the defensive oxido-reductive mechanism of human malaria parasite by repurposing nitrofurantoin

Oxidative stress mediated cell death has remained the prime parasiticidal mechanism of front line anti-malarial, artemisinin (ART). The emergence of resistant Plasmodium parasites characterized by oxidative stress management due to impaired activation of ART as well as enhanced ROS detoxification has decreased its clinical efficacy. This gap can be filled by development of alternative chemotherapeutic agents to combat resistance defense mechanism. Interestingly, repositioning of clinically approved drugs presents an emerging approach for expediting anti-malarial drug development and resistance management. Herein, we evaluated the anti-malarial potential of Nitrofurantoin (NTF), a clinically used antibacterial drug, against intra-erythrocytic stages of ART-sensitive (Pf3D7) and resistant (PfKelch13R539T) strains of Plasmodium falciparum (Pf), alone and in combination with ART. NTF exhibited growth inhibitory effect at sub micro molar concentration by arresting parasite growth at trophozoite stage. It also inhibited the survival of resistant parasites as revealed by ring survival assay. Concomitantly, in vitro combination assay revealed synergistic association of NTF with ART. NTF was found to enhance the reactive oxygen and nitrogen species as well as induced mitochondrial membrane depolarization in parasite. Furthermore, we found that exposure of parasites to NTF disrupted their redox balance by impeding Pf Glutathione Reductase activity, which manifests in enhanced oxidative stress, inducing parasite death. In vivo administration of NTF, alone and in combination with ART in P. berghei ANKA infected mice blocked parasite multiplication and enhanced mean survival time. Overall, our results indicate NTF as a promising repurposable drug with therapeutic potential against drug sensitive as well as resistant parasites.

pharmacology and toxicology↗