Kelly Saloma ̃o,1 Eniuce M. de Souza,1 Andrea Henriques-Pons,1 Helene S. Barbosa,2 and Solange L. de Castro1
1 Laborato ́rio de Biologia Celular, Instituto Oswaldo Cruz, Funda ̧ca ̃o Oswaldo Cruz, Av. Brasil 4365, Manguinhos 21045-900, Rio de Janeiro, Brazil
2 Laborato ́rio de Biologia Estrutural, Instituto Oswaldo Cruz, FIOCRUZ, CP 926, 21045-900, Rio de Janeiro, Brazil
The composition of a Brazilian green propolis ethanolic extract (Et-Bra) and its effect on Trypanosoma cruzi trypomastigotes and other pathogenic microorganisms have already been reported. Here, we further investigated Et-Bra targets in T. cruzi and its effect on experimental infection of mice. The IC(50)/4 days for inhibition of amastigote proliferation was 8.5 ± 1.8 μg mL(-1), with no damage to the host cells. In epimastigotes Et-Bra induced alterations in reservosomes, Golgi complex and mitochondrion. These effects were confirmed by flow cytometry analysis. In trypomastigotes, Et-Bra led to the loss of plasma membrane integrity. The in vitro studies indicate that Et-Bra interferes in the functionality of the plasma membrane in trypomastigotes and of reservosomes and mitochondrion in epimastigotes. Acutely infected mice were treated orally with Et-Bra and the parasitemia, mortality and GPT, GOT, CK and urea levels were monitored. The extract (25-300 mg kg(-1) body weight/day for 10 days) reduced the parasitemia, although not at significant levels; increased the survival of the animals and did not induce any hepatic, muscular lesion or renal toxicity. Since Et-Bra was not toxic to the animals, it could be assayed in combination with other drugs. Et-Bra could be a potential metacyclogenesis blocker, considering its effect on reservosomes, which are an important energy source during parasite differentiation.
* THESE STATEMENTS HAVE NOT BEEN EVALUATED BY THE FOOD AND DRUG ADMINISTRATION. THIS IS NOT INTENDED TO DIAGNOSE, TREAT CURE OR PREVENT ANY DISEASE.