The effect of free radicals induced by paraquat and copper on the in vitro development of Plasmodium falciparum.

The role of transition metals in paraquat toxicity was studied in cultures of Plasmodium falciparum. We showed that addition of copper led to an enhancement of the plasmodium killing, whereas addition of chelating agents, such as desferrioxamine and diethylenetriamine pentaacetic acid markedly reduced the toxic effects. Parsitized G6PD deficient erythrocytes were more sensitive than parasitized normal erythrocytes to copper and to the combination of copper and paraquat.