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The emergence of drug resistance in Plasmodium falciparum tremendously affected the chemotherapy worldwide while the intense distribution of chloroquine-resistant strains in most of the endemic areas added more complications in the treatment of malaria. The situation has even worsened by the lack of molecular mechanism to understand the resistance conferred by Plasmodia species. Recent studies have suggested the association of antimalarial resistance with P. falciparum multidrug resistance protein 1 (PfMDR1), an ATP-binding cassette (ABC) transporter and a homologue of human P-glycoprotein 1 (P-gp1). The present study deals about the development of PfMDR1 computational model and the model of substrate transport across PfMDR1 with insights derived from conformations relative to inward- and outward-facing topologies that switch on/off the transportation system. Comparison of ATP docked positions and its structural motif binding properties were found to be similar among other ATPases, and thereby contributes to NBD domains dimerization, a unique structural agreement noticed in Mus musculus Pgp and Escherichia coli MDR transporter homolog (MsbA). The interaction of leading antimalarials and phytochemicals within the active pocket of both wild-type and mutant-type PfMDR1 demonstrated the mode of binding and provided insights of less binding affinity thereby contributing to parasite's resistance mechanism.

India is one of the endemic areas where control of malaria has become a formidable task. Artesunate is the current antimalarial drug used to treat malaria, especially chloroquine resistant. The objective of the present study was to investigate the dose-dependent effect of oral administration of artesunate on the oxidative parameters in testes of adult male Swiss albino mice and ameliorative efficacy of curcumin, a widely used antioxidant. An oral dose of 150 mg/kg body weight (bwt; low dose) and 300 mg/kg bwt (high dose) of artesunate was administered for a period of 45 days to male mice, and ameliorative efficacy of curcumin was also assessed. The results revealed that artesunate caused significant alteration in oxidative parameters in dose-dependent manner. Administration of artesunate brought about significant decrease in activities of superoxide dismutase, glutathione, glutathione peroxidase, and glutathione reductase, whereas lipid peroxidation and glutathione-S-transferase activity were found to be significantly increased. The results obtained show that oxidative insult is incurred upon the intracellular antioxidant system of testis tissue by artesunate treatment. Further, administration of curcumin at the dose level of 80 mg/kg bwt along with both doses of artesunate attenuated adverse effects in male mice.

The present study was conducted to screen the efficacy of curcumin against chloroquine phosphate (CQ)-induced reproductive toxicity in adult male Swiss albino mice. Animals were given oral doses of 100, 200, 300 mg/kg body weight (b.w.), and high dose of CQ (300 mg/kg b.w.) + curcumin (80 mg/kg b.w.) for 45 days. Animals of the withdrawal group were given high dose of CQ (300 mg/kg b.w.) for 45 days and, at day 46, were kept for another 45 days. Effects were observed on some key enzymes, such as alkaline phosphatase, which was found to be decreased, whereas acid phosphatase was increased and succinate dehydrogenase and adenosine triphosphatase were decreased. Oxidative parameters, such as superoxide dismutase declined, whereas thiobarbituric acid-reactive substances were found to be elevated. Protein level was also decreased. Gravimetric indices were also recorded. Results obtained indicated adverse effects of CQ in a dose-dependent manner. The presence of curcumin with CQ alleviated its toxic effects. Hence, it can be concluded that curcumin has beneficial influences and appears able to ameliorate CQ toxicity.