RESUMO
Leishmaniasis is a neglected tropical disease that affects millions of people around the world. Larval excretion/secretion (ES) of the larvae of flies of the Calliphoridae family has microbicidal activity against Gram-positive and Gram-negative bacteria, in addition to some species of Leishmania. Our study aimed at assessing the in vitro efficacy of Lucilia cuprina larval ES against the promastigote and amastigote forms of Leishmania amazonensis, elucidating possible microbicidal mechanisms and routes of death involved. Larval ES was able to inhibit the viability of L. amazonensis at all concentrations, induce morphological and ultrastructural changes in the parasite, retraction of the cell body, roughness of the cytoplasmic membrane, leakage of intracellular content, ROS production increase, induction of membrane depolarization and mitochondrial swelling, the formation of cytoplasmic lipid droplets and phosphatidylserine exposure, thus indicating the possibility of apoptosis-like death. To verify the efficacy of larval ES on amastigote forms, we performed a phagocytic assay, measurement of total ROS and NO. Treatment using larval ES reduced the percentage of infection and the number of amastigotes per macrophage of lineage J774A.1 at all concentrations, increasing the production of ROS and TNF-α, thus indicating possible pro-inflammatory immunomodulation and oxidative damage. Therefore, treatment using larval ES is effective at inducing the death of promastigotes and amastigotes of L. amazonensis even at low concentrations.
Assuntos
Antiprotozoários/farmacologia , Calliphoridae/química , Larva/química , Leishmania/efeitos dos fármacos , Leishmaniose/terapia , Animais , Terapia Biológica/métodos , Secreções Corporais/química , Morte Celular/efeitos dos fármacos , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Humanos , Leishmania/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Células VeroRESUMO
Two new species of Dolichothele Mello-Leitão, 1923 are described from Brazil and Bolivia, D. mottaisp. n. from Distrito Federal and the state of Goiás, Brazil, and D. camargorumsp. n. from the state of Rondônia, Brazil, and the La Paz region, Bolivia. Males of the two new species resemble Dolichothele bolivianum (Vol, 2001) in having a small subapical keel on the distal embolus and females in particular by the short spermatheca. Dolichothele bolivianum is redescribed, and its geographical distribution is herein restricted to Bolivia and the state of Mato Grosso in Brazil.