In Vitro and In Vivo Leishmanicidal Activity ofAstronium fraxinifolium(Schott) andPlectranthus amboinicus(Lour.) Spreng againstLeishmania (Viannia) braziliensis

Abstract

The aim of the present work was to evaluate antileishmanial activity ofAstronium fraxinifoliumandPlectranthus amboinicus. For the in vitro tests, essential oil ofP. amboinicus(OEPA) and ethanolic extracts fromA. fraxinifolium(EEAF) were incubated with 106  promastigotes ofL. (Viannia) braziliensis. The OEPA was able to reduce the parasite growth after 48 h; nonetheless, all the EEAFs could totally abolish the parasite growth. For the in vivo studies, BALB/c mice were infected subcutaneously (s.c.) with 107  L. braziliensispromastigotes. Treatment was done by administering OEPA intralesionally (i.l.) for 14 days. No difference was found in lesion thickness when those animals were compared with the untreated animals. Further, golden hamsters were infected s.c. with 106  L. braziliensispromastigotes. The first protocol of treatment consisted of ethanolic leaf extract fromA. fraxinifolium(ELEAF) administered i.l. for 4 days and a booster dose at the 7th day. The animals showed a significant reduction of lesion thickness in the 6th week, but it was not comparable to the animals treated with Glucantime. The second protocol consisted of 15 daily intralesional injections. The profiles of lesion thickness were similar to the standard treatment. In conclusion, in vivo studies showed a high efficacy when the infected animals were intralesionally treated with leaf ethanolic extract fromA. fraxinifolium.