Evaluation of the toxicity of 3-allyl-beta-lapachone against Trypanosoma cruzi bloodstream forms.

In vitro incubation of Trypanosoma cruzi (Y strain) with 3-allyl-beta-lapachone was followed by: (1) growth inhibition of epimastigotes, (2) damage to cellular membranes, especially of the mitochondria, alterations in the chromatin structure and swelling of mitochondria, (3) increase in the respiratory rate, (4) increase in the rate of H2O2 generation by the epimastigotes, (5) increase of the rate of lipid peroxidation as detected by malonyldialdehyde formation, (6) decrease or total disappearance of trypomastigotes from mouse-infected blood. This drug might therefore be useful in preventing transmission of Chagas' disease during blood transfusion. It is not, however, active against infections in mice.