Síntese, caracterização e estudo da atividade inibitória de novas dialquilfosforilarilidrazonas sobre o crescimento de tripanossomatídeos

A new series of dialkylphosphorylhydrazones was synthesized through the condensation of aromatic aldehydes with different phosphorylhydrazines. All synthesized compounds were characterized by IR, ¹H-NMR, 13C-NMR and 31P-NMR spectroscopies. The in vitro investigation of the activity of these compounds against Leishmania amazonensis promastigotes and epimastigotes of T. cruzi, showed an efficient inhibition of proliferation, at non toxic concentrations to mammalian cells. The results have shown some derivatives as potential antiparasitic agents against trypanosomatids

Effects of a novel β-lapachone derivative on Trypanosoma cruzi: Parasite death involving apoptosis, autophagy and necrosis

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2017-03-16T17:23:37Z No. of bitstreams: 1 Anjos, DO Effect of a novel-B.pdf: 2604687 bytes, checksum: a792de2bdfe64e9fd85f69eada3276f8 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2017-03-16T17:40:58Z (GMT) No. of bitstreams: 1 Anjos, DO Effect of a novel-B.pdf: 2604687 bytes, checksum: a792de2bdfe64e9fd85f69eada3276f8 (MD5)Made available in DSpace on 2017-03-16T17:40:58Z (GMT). No. of bitstreams: 1 Anjos, DO Effect of a novel-B.pdf: 2604687 bytes, checksum: a792de2bdfe64e9fd85f69eada3276f8 (MD5) Previous issue date: 2016-12CNPq, PROCAD/Capes PP-SUS, PROEP, INCTINPeTAm, FAPESB, PRONEX/MCT.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, Brasil / Universidade Estadual de Santa Cruz UESC. Departamento de Ciências Biológicas. Ilhéus, BA, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilUniversidade Federal Rural do Rio de Janeiro. UFRRJ. Instituto de Química. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilUniversidade Federal Rural do Rio de Janeiro. UFRRJ. Instituto de Química. Rio de Janeiro, RJ, BrasilUniversidade Federal de Mato Grosso. UFMT. Faculdade de Medicina. Cuiabá, MG, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilNatural products comprise valuable sources for new antiparasitic drugs. Here we tested the effects of a novel β-lapachone derivative on Trypanosoma cruzi parasite survival and proliferation and used microscopy and cytometry techniques to approach the mechanism(s) underlying parasite death. The selectivity index determination indicate that the compound trypanocidal activity was over ten-fold more cytotoxic to epimastigotes than to macrophages or splenocytes. Scanning electron microscopy analysis revealed that the R72 β-lapachone derivative affected the T. cruzi morphology and surface topography. General plasma membrane waving and blebbing particularly on the cytostome region were observed in the R72-treated parasites. Transmission electron microscopy observations confirmed the surface damage at the cytostome opening vicinity. We also observed ultrastructural evidence of the autophagic mechanism termed macroautophagy. Some of the autophagosomes involved large portions of the parasite cytoplasm and their fusion/confluence may lead to necrotic parasite death. The remarkably enhanced frequency of autophagy triggering was confirmed by quantitating monodansylcadaverine labeling. Some cells displayed evidence of chromatin pycnosis and nuclear fragmentation were detected. This latter phenomenon was also indicated by DAPI staining of R72-treated cells. The apoptotis induction was suggested to take place in circa one-third of the parasites assessed by annexin V labeling measured by flow cytometry. TUNEL staining corroborated the apoptosis induction. Propidium iodide labeling indicate that at least 10% of the R72-treated parasites suffered necrosis within 24 h. The present data indicate that the β-lapachone derivative R72 selectively triggers T. cruzi cell death, involving both apoptosis and autophagy-induced necrosis

Phytochemistry

Texto completo. Acesso restrito. p. 71–77The plant Cecropia pachystachya Trécul is widely used in Brazilian ethnomedicine to treat hypertension, asthma, and diabetes. Arginase is an enzyme with levels that are elevated in these disorders, and it is central to Leishmania polyamine biosynthesis. The aims of this study were to evaluate antileishmanial activity and inhibition of the arginase enzyme by C. pachystachya extracts, and to study changes in cellular organization using electron microscopy. The ethanol extract of C. pachystachya was tested on Leishmania (Leishmania) amazonensis promastigote survival/proliferation and arginase activity in vitro. Qualitative ultrastructural analysis was also used to observe changes in cell organization. The major bioactive molecules of the ethanol extract were characterized using liquid chromatography–electrospray ionizationmass spectrometry (LC–ESI-MS). The ethyl acetate fraction of the ethanol extract diminished promastigote axenic growth/survival, inhibited arginase activity, and altered a mitochondrial kinetoplast DNA (K-DNA) array. The bioactive compounds of C. pachystachya were characterized as glucoside flavonoids. Orientin (9) (luteolin-8-C-glucoside) was the main component of the methanol-soluble ethyl acetate fraction obtained from the ethanol extract and is an arginase inhibitor (IC50 15.9 lM). The ethyl acetate fraction was not cytotoxic to splenocytes at a concentration of 200 lg/mL. In conclusion, C. pachystachya contains bioactive compounds that reduce the growth of L. (L.) amazonensis promastigotes, altering mitochondrial K-DNA arrangement and inhibiting arginase.Salvado

Leishmanicidal activity of Cecropia pachystachya flavonoids: arginase inhibition and altered mitochondrial DNA arrangement

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2013-10-23T17:55:30Z No. of bitstreams: 1 Cruz, ED Leishmanicidal activity....pdf: 753862 bytes, checksum: c99ee95789e442d656e72a0f4b9edb0c (MD5)Made available in DSpace on 2013-10-23T17:55:30Z (GMT). No. of bitstreams: 1 Cruz, ED Leishmanicidal activity....pdf: 753862 bytes, checksum: c99ee95789e442d656e72a0f4b9edb0c (MD5) Previous issue date: 2013Fundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilUniversidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária. São Paulo, SP, BRasilUniversidade de São Paulo. Faculdade de Medicina de Ribeirão Preto. Departamento de Fisiologia. Ribeirão Preto, SP, BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilUniversidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Pirassununga, SP, BrazilUniversidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos. Departamento de Medicina Veterinária. São Paulo, SP, BRasilCurso de Farmácia. Unidade de Ensino Superior Ingá. Maringa, SP, BrazilUniversidade Federal da Bahia. Instituto de Química. Departamento de Química Orgânica. Salvador, BA, BrazilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilThe plant Cecropia pachystachya Trécul is widely used in Brazilian ethnomedicine to treat hypertension, asthma, and diabetes. Arginase is an enzyme with levels that are elevated in these disorders, and it is central to Leishmania polyamine biosynthesis. The aims of this study were to evaluate antileishmanial activity and inhibition of the arginase enzyme by C. pachystachya extracts, and to study changes in cellular organization using electron microscopy. The ethanol extract of C. pachystachya was tested on Leishmania (Leishmania) amazonensis promastigote survival/proliferation and arginase activity in vitro. Qualitative ultrastructural analysis was also used to observe changes in cell organization. The major bioactive molecules of the ethanol extract were characterized using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). The ethyl acetate fraction of the ethanol extract diminished promastigote axenic growth/survival, inhibited arginase activity, and altered a mitochondrial kinetoplast DNA (K-DNA) array. The bioactive compounds of C. pachystachya were characterized as glucoside flavonoids. Orientin (9) (luteolin-8-C-glucoside) was the main component of the methanol-soluble ethyl acetate fraction obtained from the ethanol extract and is an arginase inhibitor (IC50 15.9 µM). The ethyl acetate fraction was not cytotoxic to splenocytes at a concentration of 200 µg/mL. In conclusion, C. pachystachya contains bioactive compounds that reduce the growth of L. (L.) amazonensis promastigotes, altering mitochondrial K-DNA arrangement and inhibiting arginase

Efficacy of the Photodynamic Antimicrobial Therapy (PACT) with the use of Methylene Blue Associated with the λ660nm laser in Leishmania (Leishmania) amazonensis: In Vitro Study

Santos, Marcos André Vannier dos “Documento produzido em parceria ou por autor vinculado à Fiocruz, mas não consta à informação no documento”.Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2017-06-01T16:35:58Z No. of bitstreams: 1 Santos GMP Efficacy of the photodynamic....pdf: 574870 bytes, checksum: 91e7074fb8baab6d372c0d1352381788 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2017-06-01T16:50:13Z (GMT) No. of bitstreams: 1 Santos GMP Efficacy of the photodynamic....pdf: 574870 bytes, checksum: 91e7074fb8baab6d372c0d1352381788 (MD5)Made available in DSpace on 2017-06-01T16:50:13Z (GMT). No. of bitstreams: 1 Santos GMP Efficacy of the photodynamic....pdf: 574870 bytes, checksum: 91e7074fb8baab6d372c0d1352381788 (MD5) Previous issue date: 2012Federal University of Bahia. School of Dentistry. Center of Biophotonics. Salvador, BA, BrazilFederal University of Bahia. School of Dentistry. Center of Biophotonics. Salvador, BA, BrazilFederal University of Bahia. School of Dentistry. Center of Biophotonics. Salvador, BA, BrazilFederal University of Bahia. School of Dentistry. Center of Biophotonics. Salvador, BA, BrazilFederal University of Bahia. School of Dentistry. Center of Biophotonics. Salvador, BA, BrazilFederal University of Bahia. School of Dentistry. Center of Biophotonics. Salvador, BA, BrazilFederal University of Bahia. School of Dentistry. Center of Biophotonics. Salvador, BA, BrazilFederal University of Bahia. School of Dentistry. Center of Biophotonics. Salvador, BA, BrazilFederal University of Bahia. School of Dentistry. Center of Biophotonics. Salvador, BA, BrazilThe present studied evaluated the in vitro effects of PDT on Leishmania (Leishmania) amazonensis promastigotes. For this examination L. amazonensis promastigotes, stain Josefa, were used and maintained in Warren media supplement with fetal bovine serum at 26°C for 96 hours. A viability curve was accomplished using different concentrations of methylene blue photosensitizer associated to red laser light in order to obtain the most effective interaction to inhibit the parasite’s growth. Two pre-irradiation periods, 5 and 30 minutes, were evaluated and the promastigotes were counted by colorimetry. On fluorescence microscopy the autophagic processes and reactive oxygen species were detected. Promastigotes treated with Photodynamic Therapy (PDT) by concentrations of 5 and 0,315ug/mL, presented cellular proliferation inhibition when compared to the control. In the first condition, the cells had structural alterations such as truncated cells, cells with two flagella, bleb formation and cells body deformation, while none of these modifications could be visualized in the control group. When analyzed through fluorescence microscopy, the promastigotes treated were positives for free radicals immediately after light application and also 1 hour after treatment presenting signs of autophagia. PDT on L. (L.) amazonensis is effective causing alterations that can help elucidate the mechanisms of the parasite’s death when treated with methilene blue associated to laser light. Therefore, new studies of PDT intra-parasite’s proceedings are still being accomplished

The Effectiveness of Natural Diarylheptanoids against <i>Trypanosoma cruzi</i>: Cytotoxicity, Ultrastructural Alterations and Molecular Modeling Studies

<div><p>Curcumin (CUR) is the major constituent of the rhizomes of <i>Curcuma longa</i> and has been widely investigated for its chemotherapeutic properties. The well-known activity of CUR against <i>Leishmania sp</i>., <i>Trypanosoma brucei</i> and <i>Plasmodium falciparum</i> led us to investigate its activity against <i>Trypanosoma cruzi</i>. In this work, we tested the cytotoxic effects of CUR and other natural curcuminoids on different forms of <i>T</i>. <i>cruzi</i>, as well as the ultrastructural changes induced in epimastigote form of the parasite. CUR was verified as the curcuminoid with more significant trypanocidal properties (IC₅₀ 10.13 μM on epimastigotes). Demethoxycurcumin (DMC) was equipotent to CUR (IC₅₀ 11.07 μM), but bisdemethoxycurcumin (BDMC) was less active (IC₅₀ 45.33 μM) and cyclocurcumin (CC) was inactive. In the experiment with infected murine peritoneal macrophages all diarylheptanoids were more active than the control in the inhibition of the trypomastigotes release<b>.</b> The electron microscopy images showed ultrastructural changes associated with the cytoskeleton of the parasite, indicating tubulin as possible target of CUR in <i>T</i>. <i>cruzi</i>. The results obtained by flow cytometry analysis of DNA content of the parasites treated with natural curcuminoids suggested a mechanism of action on microtubules related to the paclitaxel`s mode of action. To better understand the mechanism of action highlighted by electron microscopy and flow cytometry experiments we performed the molecular docking of natural curcuminoids on tubulin of <i>T</i>. <i>cruzi</i> in a homology model and the results obtained showed that the observed interactions are in accordance with the IC₅₀ values found, since there CUR and DMC perform similar interactions at the binding site on tubulin while BDMC do not realize a hydrogen bond with Lys163 residue due to the absence of methoxyl groups. These results indicate that trypanocidal properties of CUR may be related to the cytoskeletal alterations.</p></div

ChemPLP scores and hydrogen bond distances for curcumin derivatives from docking into <i>T</i>. <i>cruzi</i> tubulin.

<p>ChemPLP scores and hydrogen bond distances for curcumin derivatives from docking into <i>T</i>. <i>cruzi</i> tubulin.</p

Scanning electron microscopy of <i>T</i>. <i>cruzi</i> epimastigotes.

<p>Untreated control cells (A) displayed the usual elongated morphology with smooth cell surface. Parasites incubated with 10.13 μM curcumin for 24 h (B-D) presented reduced cell volume (B) as well as cell body rounding with multiple longitudinal invaginations involving the anterior portion of the parasite (C,D). Some cells displayed multiple shortened flagella (C, arrows). The protrusion of flagellar membrane was detected (D, arrows).</p

Murine peritoneal macrophages were infected with 10⁵ <i>T</i>. <i>cruzi</i> trypomastigotes (Dm28c strain).

<p>Parasite cultures were treated with 100 μM of benznidazole, CUR, DMC, BDMC and CC. After 7 days, the number of released trypomastigotes in the culture medium were determined. The data shown were obtained from three independent experiments. Cultures were compared using unpaired T-Student test (Graph Pad Prism). *P<0.05.</p

Structures of the main chemical constituents from <i>Curcuma longa</i>.

<p>Structures of the main chemical constituents from <i>Curcuma longa</i>.</p