Thioridazine treatment modifies the evolution of Trypanosoma cruzi infection in mice

Thioridazine, a tricyclic drug, is known to have a direct effect on Trypano soma cruzi, disrupting the parasites' mitochondria and kinetoplasts. In the present study, the drug was used orally, at 80 mg/kg.day for 3 days, to tr eat mice inoculated with low numbers of T. cruzi. The drug caused no appare nt toxicity in the host. It cleared trypomastigotes from the bloodstream, p revented the histological and functional alterations of the heart normally observed in the chronic phase of the experimental disease, and greatly redu ced the mortality rate compared with that in untreated, infected controls. When checked 135 days post-infection, the density of cardiac beta receptors and the cardiac histology of the treated mice were indistinguishable from those of uninfected, untreated controls. The drug is already used to treat humans, as a neuroleptic drug. It appears to be able to prevent acute infec tion with T. cruzi evolving into chronic disease, at least in mice, and may be a useful base from which to design new agents for the treatment of Chag as disease.