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Cockram PE, Smith TK. Active Natural Product Scaffolds against Trypanosomatid Parasites: A Review. JOURNAL OF NATURAL PRODUCTS 2018; 81:2138-2154. [PMID: 30234295 DOI: 10.1021/acs.jnatprod.8b00159] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Neglected tropical diseases caused by trypanosomatid parasites are a continuing and escalating problem, which devastate the less economically developed cultures in countries in which they are endemic by impairing both human and animal health. Current drugs for these diseases are regarded as out-of-date and expensive, with unacceptable side-effects and mounting parasite resistance, meaning there is an urgent need for new therapeutics. Natural products have long been a source of potent, structurally diverse bioactive molecules. Herein are reviewed natural products with reported trypanocidal activity, which have been clustered based on core structural similarities, to aid the future discovery of new trypanocidal core motifs with potential routes to synthetically accessible natural product cores suggested.
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Affiliation(s)
- Peter E Cockram
- Biomedical Sciences Research Complex , University of St Andrews , North Haugh , St Andrews , Scotland , KY16 9ST
| | - Terry K Smith
- Biomedical Sciences Research Complex , University of St Andrews , North Haugh , St Andrews , Scotland , KY16 9ST
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2
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Castillo-Garit JA, del Toro-Cortés O, Vega MC, Rolón M, Rojas de Arias A, Casañola-Martin GM, Escario JA, Gómez-Barrio A, Marrero-Ponce Y, Torrens F, Abad C. Bond-based bilinear indices for computational discovery of novel trypanosomicidal drug-like compounds through virtual screening. Eur J Med Chem 2015; 96:238-44. [PMID: 25884114 DOI: 10.1016/j.ejmech.2015.03.063] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 02/27/2015] [Accepted: 03/27/2015] [Indexed: 11/25/2022]
Abstract
Two-dimensional bond-based bilinear indices and linear discriminant analysis are used in this report to perform a quantitative structure-activity relationship study to identify new trypanosomicidal compounds. A data set of 440 organic chemicals, 143 with antitrypanosomal activity and 297 having other clinical uses, is used to develop the theoretical models. Two discriminant models, computed using bond-based bilinear indices, are developed and both show accuracies higher than 86% for training and test sets. The stochastic model correctly indentifies nine out of eleven compounds of a set of organic chemicals obtained from our synthetic collaborators. The in vitro antitrypanosomal activity of this set against epimastigote forms of Trypanosoma cruzi is assayed. Both models show a good agreement between theoretical predictions and experimental results. Three compounds showed IC50 values for epimastigote elimination (AE) lower than 50 μM, while for the benznidazole the IC50 = 54.7 μM which was used as reference compound. The value of IC50 for cytotoxicity of these compounds is at least 5 times greater than their value of IC50 for AE. Finally, we can say that, the present algorithm constitutes a step forward in the search for efficient ways of discovering new antitrypanosomal compounds.
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Affiliation(s)
- Juan Alberto Castillo-Garit
- Centro de Estudio de Química Aplicada, Facultad de Química-Farmacia, Universidad Central "Marta Abreu" de Las Villas, Santa Clara, 54830, Villa Clara, Cuba; Unit of Computer-Aided Molecular "Biosilico" Discovery and Bioinformatic Research (CAMD-BIR Unit), Faculty of Chemistry-Pharmacy, Universidad Central "Marta Abreu" de Las Villas, Santa Clara, 54830, Villa Clara, Cuba; Departament de Bioquímica i Biologia Molecular, Universitat de València, E-46100, Burjassot, Spain; Institut Universitari de Ciència Molecular, Universitat de València, Edifici d'Instituts de Paterna, P.O. Box 22085, E-46071, València, Spain.
| | - Oremia del Toro-Cortés
- Centro de Estudio de Química Aplicada, Facultad de Química-Farmacia, Universidad Central "Marta Abreu" de Las Villas, Santa Clara, 54830, Villa Clara, Cuba
| | - Maria C Vega
- Centro para el Desarrollo de la Investigacion Cientifica (CEDIC) and Fundación Moisés Bertoni/Laboratorios Díaz Gill, Pai Perez 265 casi Mariscal Estigarribia, Asuncion, Paraguay
| | - Miriam Rolón
- Centro para el Desarrollo de la Investigacion Cientifica (CEDIC) and Fundación Moisés Bertoni/Laboratorios Díaz Gill, Pai Perez 265 casi Mariscal Estigarribia, Asuncion, Paraguay
| | - Antonieta Rojas de Arias
- Centro para el Desarrollo de la Investigacion Cientifica (CEDIC) and Fundación Moisés Bertoni/Laboratorios Díaz Gill, Pai Perez 265 casi Mariscal Estigarribia, Asuncion, Paraguay
| | - Gerardo M Casañola-Martin
- Unit of Computer-Aided Molecular "Biosilico" Discovery and Bioinformatic Research (CAMD-BIR Unit), Faculty of Chemistry-Pharmacy, Universidad Central "Marta Abreu" de Las Villas, Santa Clara, 54830, Villa Clara, Cuba; Departament de Bioquímica i Biologia Molecular, Universitat de València, E-46100, Burjassot, Spain; Centro de Información y Gestión Tecnológica, Ministerio de Ciencia Tecnología y Medio Ambiente (CITMA), 65100, Ciego de Ávila, Cuba
| | - José A Escario
- Departamento de Parasitología, Facultad de Farmacia, UCM, Pza. Ramón y Cajal s/n, 28040, Madrid, Spain
| | - Alicia Gómez-Barrio
- Departamento de Parasitología, Facultad de Farmacia, UCM, Pza. Ramón y Cajal s/n, 28040, Madrid, Spain
| | - Yovani Marrero-Ponce
- Enviromental and Computational Chemistry Group, Facultad de Química Farmacéutica, Universidad de Cartagena,Cartagena de Indias, Bolivar, Colombia
| | - Francisco Torrens
- Institut Universitari de Ciència Molecular, Universitat de València, Edifici d'Instituts de Paterna, P.O. Box 22085, E-46071, València, Spain
| | - Concepción Abad
- Departament de Bioquímica i Biologia Molecular, Universitat de València, E-46100, Burjassot, Spain
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Zahari Z, Jani NA, Amanah A, Latif MNA, Majid MIA, Adenan MI. Bioassay-guided isolation of a sesquiterpene lactone of deoxyelephantopin from Elephantopus scaber Linn. active on Trypanosome brucei rhodesience. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2014; 21:282-285. [PMID: 24269185 DOI: 10.1016/j.phymed.2013.09.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 08/08/2013] [Accepted: 09/19/2013] [Indexed: 06/02/2023]
Abstract
Methanolic extracts of 70 Malaysia plants were screened for their in vitro antitrypanosomal activity using Trypanosome brucei rhodesience, strain STIB 900 and mouse skeletal cell (L-6) in cytotoxicity activity assay. Results indicated that methanol extract from Elephantopus scaber Linn. (E. scaber) possessed the highest value of antitrypanosomal activity with good selectivity index (antitrypanosomal IC50 of 0.22±0.02 μg/ml, SI value of 204.55). Based on these results, E. scaber was chosen for further study by applying bioassay guided fractionation to isolate its antiprotozoal principle. The antiprotozoal principle was isolated from the ethyl acetate partition through solvent fractionation and crystallization process. The isolated active compound 1 was identified as deoxyelephantopin on the basis of its spectral analysis (FTIR, MS, 1D and 2D NMR).
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Affiliation(s)
- Zuriati Zahari
- Malaysian Institute of Pharmaceuticals and Nutraceuticals, Ministry of Science, Technology and Innovation, Malaysia
| | - Nor Akmalazura Jani
- Universiti Teknologi MARA Negeri Sembilan, Kampus Kuala Pilah, Beting, 72000 Kuala Pilah, Negeri Sembilan, Malaysia
| | - Azimah Amanah
- Malaysian Institute of Pharmaceuticals and Nutraceuticals, Ministry of Science, Technology and Innovation, Malaysia
| | - Mohd Naffidi Abdul Latif
- Malaysian Institute of Pharmaceuticals and Nutraceuticals, Ministry of Science, Technology and Innovation, Malaysia
| | | | - Mohd Ilham Adenan
- Malaysian Institute of Pharmaceuticals and Nutraceuticals, Ministry of Science, Technology and Innovation, Malaysia; Forest Research Institute Malaysia, 52109 Kepong, Selangor, Malaysia.
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4
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Baiocco P, Poce G, Alfonso S, Cocozza M, Porretta GC, Colotti G, Biava M, Moraca F, Botta M, Yardley V, Fiorillo A, Lantella A, Malatesta F, Ilari A. Inhibition of Leishmania infantum trypanothione reductase by azole-based compounds: a comparative analysis with its physiological substrate by X-ray crystallography. ChemMedChem 2013; 8:1175-83. [PMID: 23733388 DOI: 10.1002/cmdc.201300176] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Indexed: 11/11/2022]
Abstract
Herein we report a study aimed at discovering a new class of compounds that are able to inhibit Leishmania donovani cell growth. Evaluation of an in-house library of compounds in a whole-cell screening assay highlighted 4-((1-(4-ethylphenyl)-2-methyl-5-(4-(methylthio)phenyl)-1H-pyrrol-3-yl)methyl)thiomorpholine (compound 1) as the most active. Enzymatic assays on Leishmania infantum trypanothione reductase (LiTR, belonging to the Leishmania donovani complex) shed light on both the interaction with, and the nature of inhibition by, compound 1. A molecular modeling approach based on docking studies and on the estimation of the binding free energy aided our rationalization of the biological data. Moreover, X-ray crystal structure determination of LiTR in complex with compound 1 confirmed all our results: compound 1 binds to the T(SH)2 binding site, lined by hydrophobic residues such as Trp21 and Met113, as well as residues Glu18 and Tyr110. Analysis of the structure of LiTR in complex with trypanothione shows that Glu18 and Tyr110 are also involved in substrate binding, according to a competitive inhibition mechanism.
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Affiliation(s)
- Paola Baiocco
- Dipartimento di Scienze Biochimiche, Sapienza Università di Roma, Piazzale A. Moro 5, 00185 Roma, Italy
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5
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Jorge SD, Palace-Berl F, Mesquita Pasqualoto KF, Ishii M, Ferreira AK, Berra CM, Bosch RV, Maria DA, Tavares LC. Ligand-based design, synthesis, and experimental evaluation of novel benzofuroxan derivatives as anti-Trypanosoma cruzi agents. Eur J Med Chem 2013; 64:200-14. [PMID: 23644203 DOI: 10.1016/j.ejmech.2013.03.053] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 03/19/2013] [Accepted: 03/24/2013] [Indexed: 01/09/2023]
Abstract
A set of substituted-[N'-(benzofuroxan-5-yl)methylene]benzohydrazides (4a-t), previously designed and synthesized, was experimentally assayed against Trypanosoma cruzi, the etiological agent of Chagas' disease, one of the most neglected tropical diseases. Exploratory data analysis, Hansch approach and VolSurf formalism were applied to aid the ligand-based design of novel anti-T. cruzi agents. The best 2D-QSAR model showed suitable statistical measures [n = 18; s = 0.11; F = 42.19; R(2) = 0.90 and Q(2) = 0.77 (SDEP = 0.15)], and according to the optimum 3D-QSAR model [R(2) = 0.98, Q(2) = 0.93 (SDEP = 0.08)], three latent variables explained 62% of the total variance from original data. Steric and hydrophobic properties were pointed out as the key for biological activity. Based upon the findings, six novel benzofuroxan derivatives (4u-z) were designed, synthesized, and in vitro assayed to perform the QSAR external prediction. Then, the predictability for the both models, 2D-QSAR (Rpred(2) = 0.91) and 3D-QSAR (Rpred(2) = 0.77), was experimentally validated, and compound 4u was identified as the most active anti-T. cruzi hit (IC50 = 3.04 μM).
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Affiliation(s)
- Salomão Dória Jorge
- Laboratório de Planejamento e Desenvolvimento de Fármacos, Departamento de Tecnologia Bioquímico Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Av. Prof Lineu Prestes, 580, São Paulo, SP 05508-900, Brazil.
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6
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Ligand-based discovery of novel trypanosomicidal drug-like compounds: In silico identification and experimental support. Eur J Med Chem 2011; 46:3324-30. [DOI: 10.1016/j.ejmech.2011.04.057] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 04/26/2011] [Accepted: 04/26/2011] [Indexed: 01/08/2023]
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7
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Castillo-Garit JA, Vega MC, Rolon M, Marrero-Ponce Y, Kouznetsov VV, Torres DFA, Gómez-Barrio A, Bello AA, Montero A, Torrens F, Pérez-Giménez F. Computational discovery of novel trypanosomicidal drug-like chemicals by using bond-based non-stochastic and stochastic quadratic maps and linear discriminant analysis. Eur J Pharm Sci 2009; 39:30-6. [PMID: 19854271 DOI: 10.1016/j.ejps.2009.10.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 10/01/2009] [Accepted: 10/13/2009] [Indexed: 11/28/2022]
Abstract
Herein we present results of a quantitative structure-activity relationship (QSAR) studies to classify and design, in a rational way, new antitrypanosomal compounds by using non-stochastic and stochastic bond-based quadratic indices. A data set of 440 organic chemicals, 143 with antitrypanosomal activity and 297 having other clinical uses, is used to develop QSAR models based on linear discriminant analysis (LDA). Non-stochastic model correctly classifies more than 93% and 95% of chemicals in both training and external prediction groups, respectively. On the other hand, the stochastic model shows an accuracy of about the 87% for both series. As an experiment of virtual lead generation, the present approach is finally satisfactorily applied to the virtual evaluation of 9 already synthesized in house compounds. The in vitro antitrypanosomal activity of this series against epimastigote forms of Trypanosoma cruzi is assayed. The model is able to predict correctly the behaviour for the majority of these compounds. Four compounds (FER16, FER32, FER33 and FER 132) showed more than 70% of epimastigote inhibition at a concentration of 100 microg/mL (86.74%, 78.12%, 88.85% and 72.10%, respectively) and two of these chemicals, FER16 (78.22% of AE) and FER33 (81.31% of AE), also showed good activity at a concentration of 10 microg/mL. At the same concentration, compound FER16 showed lower value of cytotoxicity (15.44%), and compound FER33 showed very low value of 1.37%. Taking into account all these results, we can say that these three compounds can be optimized in forthcoming works, but we consider that compound FER33 is the best candidate. Even though none of them resulted more active than Nifurtimox, the current results constitute a step forward in the search for efficient ways to discover new lead antitrypanosomals.
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Affiliation(s)
- Juan Alberto Castillo-Garit
- Applied Chemistry Research Center, Faculty of Chemistry-Pharmacy, Central University of Las Villas, Santa Clara, 54830, Villa Clara, Cuba.
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8
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Jones DC, Ariza A, Chow WHA, Oza SL, Fairlamb AH. Comparative structural, kinetic and inhibitor studies of Trypanosoma brucei trypanothione reductase with T. cruzi. Mol Biochem Parasitol 2009; 169:12-9. [PMID: 19747949 PMCID: PMC2789240 DOI: 10.1016/j.molbiopara.2009.09.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 08/27/2009] [Accepted: 09/03/2009] [Indexed: 11/26/2022]
Abstract
As part of a drug discovery programme to discover new treatments for human African trypanosomiasis, recombinant trypanothione reductase from Trypanosoma brucei has been expressed, purified and characterized. The crystal structure was solved by molecular replacement to a resolution of 2.3A and found to be nearly identical to the T. cruzi enzyme (root mean square deviation 0.6A over 482 Calpha atoms). Kinetically, the K(m) for trypanothione disulphide for the T. brucei enzyme was 4.4-fold lower than for T. cruzi measured by either direct (NADPH oxidation) or DTNB-coupled assay. The K(m) for NADPH for the T. brucei enzyme was found to be 0.77microM using an NADPH-regenerating system coupled to reduction of DTNB. Both enzymes were assayed for inhibition at their respective S=K(m) values for trypanothione disulphide using a range of chemotypes, including CNS-active drugs such as clomipramine, trifluoperazine, thioridazine and citalopram. The relative IC(50) values for the two enzymes were found to vary by no more than 3-fold. Thus trypanothione reductases from these species are highly similar in all aspects, indicating that they may be used interchangeably for structure-based inhibitor design and high-throughput screening.
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Affiliation(s)
- Deuan C Jones
- The Wellcome Trust Biocentre, University of Dundee, Scotland, UK
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9
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Cavalli A, Lizzi F, Bongarzone S, Brun R, Luise Krauth-Siegel R, Bolognesi ML. Privileged structure-guided synthesis of quinazoline derivatives as inhibitors of trypanothione reductase. Bioorg Med Chem Lett 2009; 19:3031-5. [DOI: 10.1016/j.bmcl.2009.04.060] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Revised: 04/06/2009] [Accepted: 04/06/2009] [Indexed: 12/13/2022]
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10
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Uchiyama N. Antichagasic Activities of Natural Products against Trypanosoma cruzi. ACTA ACUST UNITED AC 2009. [DOI: 10.1248/jhs.55.31] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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11
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Castro-Pinto DB, Lima ELS, Cunha AS, Genestra M, De Léo RM, Monteiro F, Leon LL. Leishmania amazonensis trypanothione reductase: Evaluation of the effect of glutathione analogs on parasite growth, infectivity and enzyme activity. J Enzyme Inhib Med Chem 2008; 22:71-5. [PMID: 17373550 DOI: 10.1080/14756360600920180] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Trypanothione reductase (TR) is a major enzyme in trypanosomatids. Its substrate, trypanothione is a molecule containing a tripeptide (L-glutamic acid-cysteine-glycine) coupled to a polyamine, spermidine. This redox system (TR/Trypanothione) is vital for parasite survival within the host cell and has been described as a good target for chemotherapy anti-Leishmania. The use of tripeptides analogs of glutathione would result in a decrease in trypanothione synthesis and as a consequence in TR activity. In this work, besides the enzyme potential inhibition, it also evaluated the influence of those analogs on parasite growth and on its infective capacity. The results showed a significant effect on parasite growth and infectivity and in addition TR activity was highly inhibited. These results are very promising, suggesting a potential use of those analogs as therapeutic drugs against experimental diseases caused by trypanosomatids.
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12
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Castro-Pinto DB, Echevarria A, Genestra MS, Cysne-Finkelstein L, Leon LL. Trypanothione Reductase Activity is Prominent in Metacyclic Promastigotes and Axenic Amastigotes of Leishmania amazonesis. Evaluation of its Potential as a Therapeutic Target. J Enzyme Inhib Med Chem 2008; 19:57-63. [PMID: 15202494 DOI: 10.1080/14756360310001624966] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
The activity of trypanothione reductase in Leishmania amazonensis was evaluated and it was demonstrated that TR is expressed in the soluble fractions of infective promastigotes and amastigotes, while non-infective promastigotes expressed the enzyme at basal levels. This data allows an association of enzyme activity and the infective capacity of the parasite. We have also previously demonstrated that amidine compounds (N, N'-diphenyl-4-methoxy-benzamidine and pentamidine) were active against this parasite. Here, experiments concerning the effect of these compounds on TR activity, showed that both compounds significantly inhibited the enzyme. However, against glutathione reductase, only pentamidine showed a significant inhibitory action, suggesting an association with the toxic effects of this drug used in the clinic for the treatment of leishmaniasis.
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Affiliation(s)
- Denise B Castro-Pinto
- Department of Immunology, Oswaldo Cruz Institute, FIOCRUZ, Av. Brasil, 4365-Manguinhos CEP 21042-900, Rio de Janeiro, RJ, Brazil
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13
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Stump B, Kaiser M, Brun R, Krauth-Siegel RL, Diederich F. Betraying the parasite's redox system: diaryl sulfide-based inhibitors of trypanothione reductase: subversive substrates and antitrypanosomal properties. ChemMedChem 2008; 2:1708-12. [PMID: 17918760 DOI: 10.1002/cmdc.200700172] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Bernhard Stump
- Laboratorium für Organische Chemie, ETH Zürich, Hönggerberg, HCI, 8093 Zürich, Switzerland
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14
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Krauth-Siegel RL, Bauer H, Schirmer RH. Dithiol Proteins as Guardians of the Intracellular Redox Milieu in Parasites: Old and New Drug Targets in Trypanosomes and Malaria-Causing Plasmodia. Angew Chem Int Ed Engl 2005; 44:690-715. [PMID: 15657967 DOI: 10.1002/anie.200300639] [Citation(s) in RCA: 245] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Parasitic diseases such as sleeping sickness, Chagas' heart disease, and malaria are major health problems in poverty-stricken areas. Antiparasitic drugs that are not only active but also affordable and readily available are urgently required. One approach to finding new drugs and rediscovering old ones is based on enzyme inhibitors that paralyze antioxidant systems in the pathogens. These antioxidant ensembles are essential to the parasites as they are attacked in the human host by strong oxidants such as peroxynitrite, hypochlorite, and H2O2. The pathogen-protecting system consists of some 20 thiol and dithiol proteins, which buffer the intraparasitic redox milieu at a potential of -250 mV. In trypanosomes and leishmania the network is centered around the unique dithiol trypanothione (N1,N8-bis(glutathionyl)spermidine). In contrast, malaria parasites have a more conservative dual antioxidative system based on glutathione and thioredoxin. Inhibitors of antioxidant enzymes such as trypanothione reductase are, indeed, parasiticidal but they can also delay or prevent resistance against a number of other antiparasitic drugs.
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Affiliation(s)
- R Luise Krauth-Siegel
- Universität Heidelberg, Biochemie-Zentrum, Im Neuenheimer Feld 504, D-69120 Heidelberg, Germany.
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15
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Krauth-Siegel RL, Bauer H, Schirmer RH. Dithiolproteine als Hüter des intrazellulären Redoxmilieus bei Parasiten: alte und neue Wirkstoff-Targets bei Trypanosomiasis und Malaria. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200300639] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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16
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Castro H, Sousa C, Novais M, Santos M, Budde H, Cordeiro-da-Silva A, Flohé L, Tomás AM. Two linked genes of Leishmania infantum encode tryparedoxins localised to cytosol and mitochondrion. Mol Biochem Parasitol 2004; 136:137-47. [PMID: 15478793 DOI: 10.1016/j.molbiopara.2004.02.015] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tryparedoxins are components of the hydroperoxide detoxification cascades of Kinetoplastida, where they mediate electron transfer between trypanothione and a peroxiredoxin, which reduces hydroperoxides and possibly peroxynitrite. Tryparedoxins may also be involved in DNA synthesis, by their capacity to reduce ribonucleotide reductase. Here we report on the isolation of two tryparedoxin genes from Leishmania infantum, Li7XN1 and LiTXN2, which share the same genetic locus. These genes are both single copy and code for two active tryparedoxin enzymes, LiTXN1 and LiTXN2, with different biochemical and biological features. LiTXN1 is located to the cytosol and is upregulated in the infectious forms of the parasite, strongly suggesting that it might play an important role during infection. LiTXN2 is the first mitochondrial tryparedoxin described in Kinetoplastida. Biochemical assays performed on the purified recombinant proteins have shown that LiTXN1 preferentially reduces the cytosolic L. infantum peroxiredoxins, LicTXNPx1 and LicTXNPx2, whereas LiTXN2 has a higher specific activity for a mitochondrial peroxiredoxin, LimTXNPx. Kinetically, the two tryparedoxins follow a ping-pong mechanism and show no saturation. We suggest that LiTXN1 and LiTXN2 are part of two distinct antioxidant machineries, one cytosolic, the other mitochondrial, that complement each other to ensure effective defence from several sources of oxidants throughout the development of L. infantum.
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Affiliation(s)
- Helena Castro
- Institute for Molecular and Cell Biology, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
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17
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Krauth-Siegel RL, Meiering SK, Schmidt H. The parasite-specific trypanothione metabolism of trypanosoma and leishmania. Biol Chem 2003; 384:539-49. [PMID: 12751784 DOI: 10.1515/bc.2003.062] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The bis(glutathionyl)spermidine trypanothione exclusively occurs in parasitic protozoa of the order Kinetoplastida, such as trypanosomes and leishmania, some of which are the causative agents of several tropical diseases. The dithiol is kept reduced by the flavoenzyme trypanothione reductase and the trypanothione system replaces in these parasites the nearly ubiquitous glutathione/glutathione reductase couple. Trypanothione is a reductant of thioredoxin and tryparedoxin, small dithiol proteins, which in turn deliver reducing equivalents for the synthesis of deoxyribonucleotides as well as for the detoxification of hydroperoxides by different peroxidases. Depending on the individual organism and the developmental state, the parasites also contain significant amounts of glutathione, mono-glutathionylspermidine and ovothiol, whereby all four low molecular mass thiols are directly (trypanothione and mono-glutathionylspermidine) or indirectly (glutathione and ovothiol) maintained in the reduced state by trypanothione reductase. Thus the trypanothione system is central for any thiol regeneration and trypanothione reductase has been shown to be an essential enzyme in these parasites. The absence of this pathway from the mammalian host and the sensitivity of trypanosomatids toward oxidative stress render the enzymes of the trypanothione metabolism attractive target molecules for the rational development of new drugs against African sleeping sickness, Chagas' disease and the different forms of leishmaniasis.
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Affiliation(s)
- R Luise Krauth-Siegel
- Center of Biochemistry, University of Heidelberg, Im Neuenheimer Feld 504, D-69120 Heidelberg, Germany
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Uchiyama N, Matsunaga K, Kiuchi F, Honda G, Tsubouchi A, Nakajima-Shimada J, Aoki T. Trypanocidal terpenoids from Laurus nobilis L. Chem Pharm Bull (Tokyo) 2002; 50:1514-6. [PMID: 12419922 DOI: 10.1248/cpb.50.1514] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Trypanocidal constituents of dried leaves of Laurus nobilis L. (Lauraceae) were examined. Activity-guided fractionation of the methanol extract resulted in the isolation of two guaianolides, dehydrocostus lactone (1) and zaluzanin D (2), and a new p-menthane hydroperoxide, (1R,4S)-1-hydroperoxy-p-menth-2-en-8-ol acetate (3). The minimum lethal concentrations of these compounds against epimastigotes of Trypanosoma cruzi were 6.3, 2.5, and 1.4 microM, respectively.
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Affiliation(s)
- Nahoko Uchiyama
- Graduate School of Pharmaceutical Sciences, Kyoto University, Japan
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Abstract
Current treatments for the parasitic disease leishmaniasis are unsatisfactory due to their route of administration, toxicity and expense. Resistance is also developing to first-line antimonial drugs. Fortunately, a handful of antileishmanial agents, such as the orally available compound miltefosine, are currently in clinical trials. In addition, several promising drug targets and lead molecules are being studied with the goal of developing new antileishmanial agents. Drug candidates have been identified through the continued investigation of parasite sterol metabolism and parasite proteases. New antileishmanial molecules have also been discovered through the study of novel targets and pathways, such as the bisphosphonate inhibitors of isoprenoid biosynthesis. This review presents a synopsis of the drug targets and lead compounds that have been investigated over the last few years against leishmaniasis, gives a perspective on the chemotherapeutic potential of each and discusses some of the obstacles to antileishmanial drug development.
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Affiliation(s)
- Karl A Werbovetz
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, Ohio State University, 500 West 12th Avenue, Columbus, OH 43210, USA.
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