Inhibition of the in vitro growth of Plasmodium falciparum by D vitamins and vitamin D-3 derivatives.
D vitamins are effective inhibitors of the in vitro intraerythrocytic growth of Plasmodium falciparum. Disappearance of the parasitemia was observed after 48 h contact between infected cells and 5 x 10(-6) M 1 alpha-hydroxycholecalciferol, 5 x 10(-5) M 25-hydroxycholecalciferol (25-OH-D-3), 1 alpha, 25-dihydroxycholecalciferol or 2.5 x 10(-4) vitamin D-2 and D-3. A 48 h pretreatment of healthy erythrocytes with 5 x 10(-5) M 25-OH-D-3 did not change their susceptibility to invasion by the parasite and their ability to support the growth of P. falciparum. Ionomycin, a calcium ionophore, and EGTA prevented parasite development at concentrations greater than 2 x 10(-7) M and 4 x 10(-4) M, respectively, but did not antagonize the inhibitory activity of 25-OH-D-3. Addition of 25-OH-D-3 for 12 or 24 h duration to synchronized cultures, showed that the drug had a schizonticidal action, but was without effect when parasites were in the ring form.
D000818:Animals; D002112:Calcifediol; D002117:Calcitriol / Q000494:pharmacology; D002762:Cholecalciferol / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004533:Egtazic Acid / Q000494:pharmacology; D004872:Ergocalciferols / Q000494:pharmacology*; D004912:Erythrocytes / Q000187:drug effects / Q000469:parasitology*; D004987:Ethers / Q000494:pharmacology; D006801:Humans; D006887:Hydroxycholecalciferols / Q000494:pharmacology*; D015759:Ionomycin; D010963:Plasmodium falciparum / Q000187:drug effects / Q000254:growth & development*
D004872:Ergocalciferols; D004987:Ethers; D006887:Hydroxycholecalciferols; D002762:Cholecalciferol; D004533:Egtazic Acid; D015759:Ionomycin; D002117:Calcitriol; D002112:Calcifediol; C008088:alfacalcidol