In vitro antiparasitic activity and chemical composition of the essential oil obtained from the fruits of Piper cubeba.

Protozoans of the trypanosomatid family cause the neglected tropical diseases leishmaniasis and trypanosomiasis, for which few drugs are available. In this context our group has recently reported that the essential oil obtained by steam distillation of the fruits of Piper cubeba is active against Schistosoma mansoni. Therefore, we have investigated the in vitro effects of the essential oil against the trypomastigote and amastigote forms of Trypanosoma cruzi isolated from an LLCMK₂ cell line culture and the promastigote forms of Leishmania amazonensis.

In vivo activity of ursolic and oleanolic acids during the acute phase of Trypanosoma cruzi infection.

Reduction in the parasitemic levels of the Y strain of Trypanosoma cruzi in mice treated with oral or intraperitoneal ursolic (UA) and oleanolic (OA) acids was evaluated during the acute phase of Chagas' disease. Oral administration of UA and OA (50mg/kg/day) provided the most significant reduction in the parasitemic peak, while intraperitoneal administration of UA and OA did not significantly affect the biological activity of the Y strain of T. cruzi.

Evaluation of the in vivo therapeutic properties of (-)-cubebin and (-)-hinokinin against Trypanosoma cruzi.

Even though the Chagas' disease, caused by the protozoan Trypanosoma cruzi, was described 100years ago by Carlos Chagas, it still represents a major public health concern and is found in 18 developing countries in South and Central America. In Brazil, Benznidazole (Rochagan) is the only drug with trypanocidal activity available in the market, despite its several side effects and limited efficacy in the chronic phase of the infection. In view of the need for new substances displaying biological activity against T.

In vivo infection by Trypanosoma cruzi: a morphometric study of tissue changes in mice.

Nifurtimox and benznidazole, medications currently used for the treatment of the Chagas disease, are not always successful. We determine whether (-)-cubebin and (-)-hinokinin could be used as alternative drugs for the treatment of parasitic infections by Trypanosoma cruzi. To this end, male BALB/c mice were treated with both drugs, and the nuclear parameters (largest diameter, smallest diameter, and perimeter) were determined from slides prepared from the spleen, liver, and heart.

Reduction of parasitism tissue by treatment of mice chronically infected with Trypanosoma cruzi with lignano lactones.

The reduction of parasitism tissue upon treatment with two lignano lactones, namely (-)- cubebin (CUB) and (-)-hinokinin (HNK), was evaluated in the chronic phase of Chagas' disease by quantifying the enzyme beta-galactosidase expressed by the CL B5 clone strain of Trypanosoma cruzi. Tissue karyometry was also performed. Treatment with the assessed lignans led to a larger reduction in parasitism tissue in all evaluated organs, compared with benznidazole (BZN).

New method for quantification of Trypanosoma cruzi in animal's tissue in the chronic phase of experimental Chagas' disease.

We developed a new method for the quantification of parasites in tissue. Trypanosoma cruzi strain CL parasites were genetically engineered to express the Escherichia coli beta-galactosidase gene, lacZ and this enzyme is able to catalyze a colorimetric reaction with chlorophenol red beta-D: galactopyranoside (CPRG) as the substrate. The animals were infected with clone CL Brener strain B5 of T.

(-)-Hinokinin-loaded poly(D,-lactide-co-glycolide) microparticles for Chagas disease.

The (-)-hinokinin display high activity against Trypanosoma cruzi in vitro and in vivo. (-)-Hinokinin-loaded poly(D,L-lactide-co-glycolide) microparticles were prepared and characterized in order to protect (-)-hinokinin of biological interactions and promote its sustained release for treatment of Chagas disease. The microparticles contain (-)-hinokinin were prepared by the classical method of the emulsion/solvent evaporation.

Melatonin and dehydroepiandrosterone combination: does this treatment exert a synergistic effect during experimental Trypanosoma cruzi infection?

Previous studies showed that melatonin or dehydroepiandrosterone (DHEA) enhances the immune response against parasitic pathogens. The present study investigated the in vitro activity of melatonin combined with DHEA in a period of 24 hr during the course of in vivo T. cruzi infection.

In vitro trypanocidal activity of triterpenes from miconia species.

The bioassay-guided fractionation of methylene chloride extracts of Miconia fallax DC. and Miconia stenostachya DC. led to the isolation of five triterpene acids.