Article

Activity of physalins purified from Physalis angulata in in vitro and in vivo models of cutaneous leishmaniasis.

Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, BA, Brazil.
Journal of Antimicrobial Chemotherapy (Impact Factor: 5.34). 06/2009; 64(1):84-7. DOI: 10.1093/jac/dkp170
Source: PubMed

ABSTRACT We have previously demonstrated the immunomodulatory effects of physalins, secosteroids purified from Physalis angulata. Here we investigate the antileishmanial activity of physalins in vitro and in vivo in a model of cutaneous leishmaniasis.
The antileishmanial activity of physalins B, D and F was tested in Leishmania-infected macrophage cultures. For the in vivo studies, BALB/c mice were infected with Leishmania amazonensis subcutaneously in the ear pinna and treated with physalin F by topical administration.
Physalins B and F were able to reduce the percentage of Leishmania-infected macrophages and the intracellular parasite number in vitro at concentrations non-cytotoxic to macrophages. More importantly, topical treatment with physalin F significantly reduced the lesion size, the parasite load and histopathological alterations in BALB/c mice infected with L. amazonensis.
Our results demonstrate the potent antileishmanial activity of physalins, especially physalin F, and suggest these molecules as the basis for the development of new therapeutic options for cutaneous leishmaniasis.

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