Larval excretion/secretion of dipters of Lucilia cuprina species induces death in promastigote and amastigote forms of Leishmania amazonensis

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.

Temporal and spatial distribution of American tegumentary leishmaniasis in north Paraná: 2010-2015

Abstract INTRODUCTION: Describing the general aspects of American tegumentary leishmaniasis enables the identification of the epidemiological scenario of the disease and the development of preventive actions. METHODS: We analyzed the records of patients with American tegumentary leishmaniasis in north Paraná between 2010 and 2015. RESULTS: We identified 108 cases (mostly in 2014) with the following characteristics: male individuals, rural workers, and ages averaging 56.8 years. Isolated ulcerated lesions were predominant, and Glucantime® was the most frequently used drug. CONCLUSIONS: American tegumentary leishmaniasis remains endemic and affects mostly men found in areas surrounded by woods; its treatment is partially efficient considering its side effects and incidence of recurrences.