About 1.5 million new cases of cutaneous leishmaniasis and 500,000 new cases of visceral leishmaniasis occur each year around the world. For over half a century, the clinical forms of the disease have been treated almost exclusively with pentavalent antimonial compounds. In this review, we describe the arsenal available for treating Leishmania infections, as well as recent advances from research on plants and synthetic compounds as source drugs for treating the disease. We also review some new drug-delivery systems for the development of novel chemotherapeutics. We observe that the pharmaceutical industry should employ its modern technologies, which could lead to better use of plants and their extracts, as well as to the development of synthetic and semi-synthetic compounds. New studies have highlighted some biopharmaceutical technologies in the design of the delivery strategy, such as nanoparticles, liposomes, cochleates, and non-specific lipid transfer proteins. These observations serve as a basis to indicate novel routes for the development and design of effective anti-Leishmania drugs.

The antimicrobial activity of copaiba oils was tested against Gram-positive and Gram-negative bacteria, yeast, and

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The essential oil (EO)

The in vitro activity of parthenolide against Leishmania amazonensis was investigated. Parthenolide is a sesquiterpene lactone purified from the hydroalcoholic extract of aerial parts of Tanacetum parthenium. This isolated compound was identified through spectral analyses by UV, infrared, 1 H and 13 C nuclear magnetic resonance imaging, DEPT (distortionless enhancement by polarization transfer), COSY (correlated spectroscopy), HMQC (heteronuclear multiple-quantum coherence), and electron spray ionization-mass spectrometry. Parthenolide showed significant activity against the promastigote form of L. amazonensis, with 50% inhibition of cell growth at a concentration of 0.37 g/ml. For the intracellular amastigote form, parthenolide reduced by 50% the survival index of parasites in macrophages when it was used at 0.81 g/ml. The purified compound showed no cytotoxic effects against J774G8 macrophages in culture and did not cause lysis in sheep blood when it was used at higher concentrations that inhibited promastigote forms. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis with gelatin as the substrate showed that the enzymatic activity of the enzyme cysteine protease increased following treatment of the promastigotes with the isolated compound. This finding was correlated with marked morphological changes induced by parthenolide, such as the appearance of structures similar to large lysosomes and intense exocytic activity in the region of the flagellar pocket, as seen by electron microscopy. These results provide new perspectives on the development of novel drugs with leishmanicidal activities obtained from natural products.

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To discover new possible therapies for Chagas' disease, we evaluated against all Trypanosoma cruzi life stages the in vitro trypanocidal and synergistic activity of terpenes isolated from Copaifera oleoresins collected in the Amazon and investigated their possible mechanism of action. Seven acid diterpenes and one sesquiterpene were tested. Terpenes promoted changes in oxidative metabolism followed by autophagic processes in the parasite cell leading to selective death. Furthermore, they were more effective against replicative forms, in particular amastigotes. A synergistic effect occurred. Cytotoxicity to erythrocytes and nucleated cells was moderate. This is the first study showing synergic activity between two terpenes against T. cruzi. Combinations of natural compounds can show high activity and may lead to new alternative treatments in the future.