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Almeida-Souza F.,Instituto Oswaldo Cruz | Almeida-Souza F.,State University of Maranhao | Taniwaki N.N.,Instituto Adolf Lutz | Amaral A.C.F.,Laboratorio Of Plantas Medicinais E Derivados | And 3 more authors.
Evidence-based Complementary and Alternative Medicine | Year: 2016

The search for new treatments against leishmaniasis has increased due to high frequency of drug resistance registered in endemics areas, side effects, and complications caused by coinfection with HIV. Morinda citrifolia Linn., commonly known as Noni, has a rich chemical composition and various therapeutic effects have been described in the literature. Studies have shown the leishmanicidal activity of M. citrifolia; however, its action on the parasite has not yet been elucidated. In this work, we analyzed leishmanicidal activity and ultrastructural changes in Leishmania infantum promastigotes caused by M. citrifolia fruit juice treatment. M. citrifolia fruit extract showed a yield of 6.31% and high performance liquid chromatography identified phenolic and aromatic compounds as the major constituents. IC50 values were 260.5 μg/mL for promastigotes and 201.3 μg/mL for intracellular amastigotes of L. infantum treated with M. citrifolia. Cytotoxicity assay with J774.G8 macrophages showed that M. citrifolia fruit juice was not toxic up to 2 mg/mL. Transmission electron microscopy showed cytoplasmic vacuolization, lipid inclusion, increased exocytosis activity, and autophagosome-like vesicles in L. infantum promastigotes treated with M. citrifolia fruit juice. M. citrifolia fruit juice was active against L. infantum in the in vitro model used here causing ultrastructural changes and has a future potential for treatment against leishmaniasis. © 2016 Fernando Almeida-Souza et al.

Silva J.R.A.,Federal University of Amazonas | Rezende C.M.,Federal University of Rio de Janeiro | Pinto A.C.,Federal University of Rio de Janeiro | Amaral A.C.F.,Laboratorio Of Plantas Medicinais E Derivados
African Journal of Biotechnology | Year: 2010

The latex of Himatanthus sucuuba (Spruce) Woodson, used popularly in the Amazon for the treatment of tumors, gastritis, inflammations and infections, was evaluated for cytotoxicity and antibacterial activities. The iridoid lactones, plumericin and isoplumericin were isolated from latex by bioassay fractionation and were found to be associated with DNA damage. Gallic acid exhibited the highest antimicrobial activity among the phenolic compounds isolated from the aqueous fraction. The compounds associated to cytotoxicity and antimicrobial activities could be responsible to the effects of this species used in traditional medicine. © 2010 Academic Journals.

Oliveira E.S.C.,Federal University of Amazonas | Amaral A.C.F.,Laboratorio Of Plantas Medicinais E Derivados | Lima E.S.,Federal University of Amazonas | De A. Silva J.R.,Federal University of Amazonas
Journal of Essential Oil Research | Year: 2014

This article describes, for the first time, the chemical constituents of the essential oils from fresh leaves of Bocageopsis multiflora, collected in two seasons, and some of its biological activities. The oils were analyzed by gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (MS) and showed a high proportion of sesquiterpenes. The main constituent of the oil collected in the rainy season was bisabolene (13.2%), while the main constituent in the dry season was spathulenol (16.2%). The highest yield (0.3%) was obtained for the oil collected in the rainy season, which was assayed against Leishmania amazonensis promastigote forms, exhibiting significant activity (IC50 of 14.6 ìg/mL). Comparison between the oil and the reference drug (pentamidine isethionate) showed non-toxic effects for mice peritoneal macrophages treated at IC50 of each sample. The results obtained in the prothrombin time and activated partial thromboplastin time tests indicated that the oil acted as a procoagulant, causing activation of coagulation in both pathways. © 2014 Taylor & Francis.

Do Carmo D.F.M.,Federal University of Amazonas | Amaral A.C.F.,Laboratorio Of Plantas Medicinais E Derivados | MacHado G.M.C.,Laboratorio Of Bioquimica Of Tripanosomatideos | Leon L.L.,Laboratorio Of Bioquimica Of Tripanosomatideos | De Andrade Silva J.R.,Federal University of Amazonas
Molecules | Year: 2012

The essential oils obtained from leaves of Piper duckei and Piper demeraranum by hydrodistillation were analyzed by gas chromatography-mass spectrometry. The main constituents found in P. demeraranum oil were limonene (19.3%) and β-elemene (33.1%) and in P. duckei oil the major components found were germacrene D (14.7%) and trans-caryophyllene (27.1%). P. demeraranum and P. duckei oils exhibited biological activity, with IC 50 values between 15 to 76 μg mL -1 against two Leishmania species, P. duckei oil being the most active. The cytotoxicity of the essential oils on mice peritoneal macrophage cells was insignificant, compared with the toxicity of pentamidine. The main mono- and sesquiterpene, limonene (IC 50 = 278 μM) and caryophyllene (IC 50 = 96 μM), were tested against the strains of Leishmania amazonensis, and the IC 50 values of these compounds were lower than those found for the essential oils of the Piper species. The HET-CAM test was used to evaluate the irritation potential of these oils as topical products, showing that these oils can be used as auxiliary medication in cases of cutaneous leishmaniasis, with less side effects and lower costs.

Rottini M.M.,Instituto Oswaldo Cruz | Amaral A.C.F.,Laboratorio Of Plantas Medicinais E Derivados | Ferreira J.L.P.,Laboratorio Of Plantas Medicinais E Derivados | Silva J.R.D.A.,Laboratory Of Cromatografia | And 7 more authors.
Experimental Parasitology | Year: 2015

Current treatments for leishmaniasis present some difficulties due to their toxicity, the use of the intravenous route for administration and therapy duration, which may lead to treatment discontinuation. The aim of this study is to investigate new treatment alternatives to improve patients well being. Therefore, we evaluated the inhibitory effect of (-)α-bisabolol, a sesquiterpene alcohol found in various essential oils of different plant species, against the promastigotes and intracellular amastigotes forms of Leishmania amazonensis, as well as the cytotoxic, morphological and ultrastructural alterations of treated cells. Promastigotes forms of L.amazonensis were incubated with (-)α-bisabolol to determine the antileishmanial activity of this compound. The cytotoxicity effect was evaluated by testing against J774.G8 cells. After these tests, the infected and uninfected cells with L.amazonensis were used to determine if the (-)α-bisabolol was able to kill intracellular parasites and to cause some morphological changes in the cells. The (-)α-bisabolol compound showed significant antileishmanial activity against promastigotes with a 50% effective concentration of 8.07μg/ml (24h) and 4.26μg/ml (48 h). Against intracellular amastigotes the IC50 (inhibitory concentration) of (-)α-bisabolol (24h) was 4.15μg/ml. The (-)α-bisabolol also showed a cytotoxic effect against the macrophage strain J774.G8. The value of 50% cytotoxic concentration was 14.82μg/ml showing that (-)α-bisabolol is less toxic to macrophages than to the parasite. Ultrastructural studies of treated promastigotes and amastigotes showed several alterations, such as loss of cytoplasmic organelles, including the nucleus, and the presence of lipid inclusions. This study showed that (-)α-bisabolol has promising antileishmanial properties, as it can act against the promastigote forms and is able to penetrate the cell, and is also active against the amastigote forms. About 69% of the promastigotes forms suffered mitochondrial membrane damage after treatment with IC50 of (-)α-bisabolol, suggesting inhibition of the metabolic activity of parasites. These results open new prospects for research that can contribute to the development of products based on essential oils or isolated compounds from plants for the treatment of cutaneous leishmaniasis. © 2014 Elsevier Inc.

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