Efeito da peçonha de Bothrops moojeni sobre formas promastigotas de Leishmania spp

by Castilhos, Patrícia de

Abstract (Summary)
In order to develop alternative tools to subdue infectious diseases, several substanceshave been tested toward treatment of parasitoses, such as Leishmaniasis. For this purpose, snakevenoms have been used as future drugs that disrupt the viability of protozoan. In this report, weevaluated the effect of Bothrops moojeni venom and its fractions on viability, protein profile,infectivity and nitric oxide production of Leishmania promastigotes ?in vitro?. Bothrops moojenivenom was fractionated into five protein fractions (E1 to E5) by ion exclusion chromatographyand used to treat on L. (L.) amazonensis and L. (V.) braziliensis promastigote forms. Theviability of Leishmania promastigotes was evaluated by MTT test and nitric oxide productionwas detected in supernatants of Leishmania culture. It was observed that E5 fraction stronglyinhibited NO production in different concentrations in L. amazonensis, while in L. brasiliensisthe NO production was enhance in ever concentration. It was also observed that crude venom ofB. moojeni inhibited the viability of the both parasites in a dose dependent manner. However theE5 fraction only inhibited the viability of L. amazonensis. Also a peptide of 64 kDa of L (L.)amazonensis was apparently degraded in other two peptides with 56 and 51 kDa respectively.Moreover, when Leishmania spp was treated with E5 fraction and amphotericin B was notobserved degradation of proteins. And after studies with the E5 fraction in DEAE (-) Sephacel, itwas realized the exclusion cromatography and was obtained six new fractions (E5G1 and E5G6)and the cellular viability Leishmania (L.) amazonensis was sensitive to E5G1 (amp;#8805; 0.156 amp;#956;g) andE5G5 (amp;#8805; 0.313amp;#956;g). Adicionaly, it was analyzed the effect of Bothrops moojeni venon and the E5fraction in the lesion progression of BALB/c mice infected with L. amazonensis and during thefollowing period of lesion evolution (six weeks) it was verified that the thickness of the footpads of all infected animals with pre treated parasites did not increase in comparison to the noninfected contralateral footpad. Thus, we demonstrated that Bothrops moojeni venom inhibitedNO production, altered the protein profile and reduced the viability and infectivity of Leishmaniapromastigotes ?in vitro?.
This document abstract is also available in Portuguese.
Bibliographical Information:

Advisor:Fábio de Oliveira; Clarice Abramo; Maria Aparecida de Souza

School:Universidade Federal de Uberlândia

School Location:Brazil

Source Type:Master's Thesis

Keywords: B. moojeni Nitric oxide Promastigote viability


Date of Publication:07/31/2008

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