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Bhattacharya A, Sharma M, Pakkinathan C, Rosen BP, Leprohon P, Ouellette M. Genomewide Analysis of Mode of Action of the S-Adenosylmethionine Analogue Sinefungin in Leishmania infantum. mSystems 2019; 4:e00416-19. [PMID: 31615876 PMCID: PMC6794121 DOI: 10.1128/msystems.00416-19] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 09/30/2019] [Indexed: 11/20/2022] Open
Abstract
To further our understanding of one-carbon metabolism in the protozoan parasite Leishmania, we conducted genomic screens to study how the parasite responded to sinefungin (SNF) selection. SNF is a structural analogue of S-adenosylmethionine (AdoMet), a key methyl group donor to a number of biomolecules. One screen consisted of sequencing SNF-resistant mutants generated by stepwise selection with gradually increasing drug concentrations. These studies demonstrated deletion of the AdoMet transporter (AdoMetT1) by intergenic recombination as a crucial loss-of-function marker for SNF resistance. The second screen consisted of Cos-seq, a gain-of-function cosmid-based genomewide functional screen with increasing SNF concentration coupled to next-generation sequencing. Cosmids enriched in that screen and sequenced led to the identification of (i) the AdoMet synthetase (METK) as the major SNF target, (ii) an mRNA [(guanine-N7)-methyltransferase (CMT1)], (iii) a leucine carboxyl methyltransferase (LCMT), (iv) two tryparedoxin genes, and (v) two protein phosphatase regulatory genes. Further functional exploration indicated that LCMT interacts with one phosphatase catalytic subunit (PP2AC) and that mutation of the C-terminal leucine residue of PP2AC affects sinefungin susceptibility. These holistic screens led to the identification of transporters, biosynthetic genes, RNA and protein methyltransferases, as well as phosphatases linked to AdoMet-mediated functions in Leishmania IMPORTANCE The two main cellular metabolic one-carbon donors are reduced folates and S-adenosylmethionine, whose biosynthetic pathways have proven highly effective in chemotherapeutic interventions in various cell types. Sinefungin, a nucleoside analogue of S-adenosylmethionine, was shown to have potent activity against the protozoan parasite Leishmania Here, we studied resistance to sinefungin using whole-genome approaches as a way to further our understanding of the role of S-adenosylmethionine in this parasite and to reveal novel potential drug targets. These approaches allowed the characterization of novel features related to S-adenosylmethionine function in Leishmania which could further help in the development of sinefungin-like compounds against this pathogenic parasite.
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Affiliation(s)
- Arijit Bhattacharya
- Division of Infectious Disease and Immunity, CHU de Quebec Research Center, Quebec, Quebec, Canada
- Department of Microbiology, Infectious Disease and Immunology, University Laval, Quebec, Quebec, Canada
| | - Mansi Sharma
- Division of Infectious Disease and Immunity, CHU de Quebec Research Center, Quebec, Quebec, Canada
- Department of Microbiology, Infectious Disease and Immunology, University Laval, Quebec, Quebec, Canada
| | - Charles Pakkinathan
- Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida, USA
| | - Barry P Rosen
- Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida, USA
| | - Philippe Leprohon
- Division of Infectious Disease and Immunity, CHU de Quebec Research Center, Quebec, Quebec, Canada
- Department of Microbiology, Infectious Disease and Immunology, University Laval, Quebec, Quebec, Canada
| | - Marc Ouellette
- Division of Infectious Disease and Immunity, CHU de Quebec Research Center, Quebec, Quebec, Canada
- Department of Microbiology, Infectious Disease and Immunology, University Laval, Quebec, Quebec, Canada
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Sala L, Franco-Valls H, Stanisavljevic J, Curto J, Vergés J, Peña R, Duch P, Alcaraz J, García de Herreros A, Baulida J. Abrogation of myofibroblast activities in metastasis and fibrosis by methyltransferase inhibition. Int J Cancer 2019; 145:3064-3077. [PMID: 31032902 DOI: 10.1002/ijc.32376] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 03/28/2019] [Accepted: 04/15/2019] [Indexed: 12/14/2022]
Abstract
Myofibroblasts are a population of highly contractile fibroblasts that express and require the activity of the transcription factor Snail1. Cancer-associated fibroblasts (CAFs) correlate with low survival of cancer patients when present in the stroma of primary tumors. Remarkably, the presence of myofibroblastic CAFs (which express Snail1) creates mechanical properties in the tumor microenvironment that support metastasis. However, therapeutic blockage of fibroblast activity in patients with cancer is a double-edged sword, as normal fibroblast activities often restrict tumor cell invasion. We used fibroblasts depleted of Snail1 or protein arginine methyltransferases 1 and 4 (PRMT1/-4) to identify specific epigenetic modifications induced by TGFβ/Snail1. Furthermore, we analyzed the in vivo efficiency of methyltransferase inhibitors using mouse models of wound healing and metastasis, as well as fibroblasts isolated from patients with idiopathic pulmonary fibrosis (IPF). Mechanistically, TGFβ-induced Snail1 promotes the epigenetic mark of asymmetrically dimethylated arginine. Critically, we found that inhibitors of methyltransferases prevent myofibroblast activity (but not regular fibroblast activity) in the extracellular matrix, both in cell culture and in vivo. In a mouse breast cancer model, the inhibitor sinefungin reduces both the myofibroblast activity in the tumor stroma and the metastatic burden in the lung. Two distinct inhibitors effectively blocked the exacerbated myofibroblast activity of patient-derived IPF fibroblasts. Our data reveal epigenetic regulation of myofibroblast transdifferentiation in both wound healing and in disease (fibrosis and breast cancer). Thus, methyltransferase inhibitors are good candidates as therapeutic reagents for these diseases.
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Affiliation(s)
- Laura Sala
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - Héctor Franco-Valls
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - Jelena Stanisavljevic
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain.,Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Josue Curto
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain.,Department of Cancer Biology, MD Anderson Cancer Center, Houston, Texas
| | - Jordi Vergés
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - Raúl Peña
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - Paula Duch
- Unitat de Biofísica i Bioenginyeria, Departament de Biomedicina, Facultat de Medicina i Ciències de la Salut - Universitat de Barcelona (UB), Barcelona, Spain
| | - Jordi Alcaraz
- Unitat de Biofísica i Bioenginyeria, Departament de Biomedicina, Facultat de Medicina i Ciències de la Salut - Universitat de Barcelona (UB), Barcelona, Spain.,CIBER de Enfermedades Respiratorias, Madrid, Spain
| | - Antonio García de Herreros
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain.,Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain
| | - Josep Baulida
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
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Zhao Z, Martin C, Fan R, Bourne PE, Xie L. Drug repurposing to target Ebola virus replication and virulence using structural systems pharmacology. BMC Bioinformatics 2016; 17:90. [PMID: 26887654 PMCID: PMC4757998 DOI: 10.1186/s12859-016-0941-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Accepted: 02/10/2016] [Indexed: 01/09/2023] Open
Abstract
Background The recent outbreak of Ebola has been cited as the largest in history. Despite this global health crisis, few drugs are available to efficiently treat Ebola infections. Drug repurposing provides a potentially efficient solution to accelerating the development of therapeutic approaches in response to Ebola outbreak. To identify such candidates, we use an integrated structural systems pharmacology pipeline which combines proteome-scale ligand binding site comparison, protein-ligand docking, and Molecular Dynamics (MD) simulation. Results One thousand seven hundred and sixty-six FDA-approved drugs and 259 experimental drugs were screened to identify those with the potential to inhibit the replication and virulence of Ebola, and to determine the binding modes with their respective targets. Initial screening has identified a number of promising hits. Notably, Indinavir; an HIV protease inhibitor, may be effective in reducing the virulence of Ebola. Additionally, an antifungal (Sinefungin) and several anti-viral drugs (e.g. Maraviroc, Abacavir, Telbivudine, and Cidofovir) may inhibit Ebola RNA-directed RNA polymerase through targeting the MTase domain. Conclusions Identification of safe drug candidates is a crucial first step toward the determination of timely and effective therapeutic approaches to address and mitigate the impact of the Ebola global crisis and future outbreaks of pathogenic diseases. Further in vitro and in vivo testing to evaluate the anti-Ebola activity of these drugs is warranted. Electronic supplementary material The online version of this article (doi:10.1186/s12859-016-0941-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zheng Zhao
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, P. R. China.,National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Che Martin
- The Graduate Center, The City University of New York, New York, USA
| | - Raymond Fan
- Department of Chemistry, Hunter College, The City University of New York, New York, USA
| | - Philip E Bourne
- Office of the Director, National Institutes of Health, Bethesda, MD, USA
| | - Lei Xie
- The Graduate Center, The City University of New York, New York, USA. .,Department of Computer Science, Hunter College, The City University of New York, New York, USA.
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Reguera RM, Redondo CM, Pérez-Pertejo Y, Balaña-Fouce R. S-Adenosylmethionine in protozoan parasites: Functions, synthesis and regulation. Mol Biochem Parasitol 2007; 152:1-10. [PMID: 17196271 DOI: 10.1016/j.molbiopara.2006.11.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Revised: 11/28/2006] [Accepted: 11/30/2006] [Indexed: 10/23/2022]
Abstract
S-adenosylmethionine is one of the most frequently used enzymatic substrates in all living organisms. It plays a role in all biological methyl transfer reactions in as much as it is a donor of propylamine groups in the synthesis of the polyamines spermidine and spermine, it participates in the trans-sulphuration pathway to cysteine one of the three amino acids involved in glutathione and trypanothione synthesis in trypanosomatids and finally it is a source of the 5-deoxyadenosyl radicals, which are involved in many reductive metabolic processes, biodegradative pathways, tRNA modification and DNA repair. This mini-review is an update of the progress on the S-adenosylmethionine synthesis in different representative protozoan parasites responsible for many of the most devastating so-called tropical diseases that have an enormous impact on global health.
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Affiliation(s)
- Rosa M Reguera
- Department of Pharmacology and Toxicology, University of León, Campus de Vegazana s/n, 24071 León, Spain
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Rocha LG, Almeida JRGS, Macêdo RO, Barbosa-Filho JM. A review of natural products with antileishmanial activity. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2005; 12:514-35. [PMID: 16008131 DOI: 10.1016/j.phymed.2003.10.006] [Citation(s) in RCA: 192] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Infections caused by protozoa of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The incidence of the disease has increased since the emergence of AIDS. In the absence of a vaccine, there is an urgent need for effective drugs to replace/supplement those in current use. The plant kingdom is undoubtedly valuable as a source of new medicinal agents. The present work constitutes a review of the literature on plant extracts and chemically defined molecules of natural origin showing antileishmanial activity. The review refers to 101 plants, their families, and geographical distribution, the parts utilized, the type of extract and the organism tested. It also includes 288 compounds isolated from higher plants and microorganisms, classified into appropriate chemical groups. Some aspects of recent antileishmanial-activity-directed research on natural products are discussed.
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Affiliation(s)
- L G Rocha
- Departamento de Microbiologia e Parasitologia, Universidade Federal do Rio Grande do Norte, 59000-000 Natal, RN, Brazil
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Lawrence F, Derbécourt T, Robert-Gero M. Proton-ATPase activities involved in the uptake of an S-adenosylmethionine analogue. Mol Biochem Parasitol 1998; 92:99-109. [PMID: 9574914 DOI: 10.1016/s0166-6851(97)00235-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Characteristics of the transport of sinefungin (SF) were studied in Leishmania donovani promastigotes grown in vitro in a semi-defined medium. The uptake is time and pH dependent, temperature sensitive, saturable and independent of the growth phase. Metabolic inhibitors decrease the influx, indicating that sinefungin uptake is an energy requiring process. The presence of Na+ is unnecessary for activity. The uptake is sensitive to valinomycin and nigericin and to the H+-ATPases inhibitors such as N'N'-dicyclohexylcarbodiimide, bafilomycin A and oligomycin. Sulfhydryl group(s) are involved in carrier activity. Use of SF analogues shows, stereospecificity of the transporter, recognition of the 6'-amino group and to a lesser degree of the 9'-amino group of the lateral chain, whereas the 9'-carboxyl group of the lateral chain is not implicated in the recognition. Adenosine and ornithine do not interfere with the uptake. No significant amount of SF is tightly bound to macromolecules. In a SF-resistant clone, though the uptake of SF is reduced (the apparent Vmax is 276 pmoles mg protein(-1) 30 min(-1) compared with 2061 pmoles mg protein(-1) 30 min(-1) for the wild-type clone), the apparent affinity for SF is similar to that of wild-type cells (Km 0.7 and 0.6 microM respectively). This lower uptake activity is not the reflection of an increased efflux of the drug. In these resistant cells, the susceptibility of SF uptake to variation of the external pH, as well as to azide, NaF, and valinomycin are decreased, that to nigericin is lost.
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Affiliation(s)
- F Lawrence
- Institut de Chimie des Substances Naturelles, CNRS, Gif-sur Yvette, France
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Phelouzat MA, Basselin M, Lawrence F, Robert-Gero M. Sinefungin shares AdoMet-uptake system to enter Leishmania donovani promastigotes. Biochem J 1995; 305 ( Pt 1):133-7. [PMID: 7826320 PMCID: PMC1136440 DOI: 10.1042/bj3050133] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The involvement of a carrier for sinefungin (SF) uptake in Leishmania donovani promastigotes is indicated by saturation kinetics, competition studies and SF accumulation against a 270-fold concentration gradient across the cell membrane. Whether SF uptake occurs via nucleoside- or AdoMet-carrier systems was investigated by competition experiments and comparison of the uptake of various molecules in wild-type and SF-resistant cells. Results show that SF did not inhibit purine or pyrimidine uptake whereas it competitively inhibited AdoMet uptake. Furthermore, the uptake of nucleosides in SF-resistant cells is similar to that in wild-type cells, whereas uptake of SF and AdoMet is lower.
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Affiliation(s)
- M A Phelouzat
- Institut de Chimie des Substances Naturelles, C.N.R.S., Gif-sur Yvette, France
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8
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Soteriadou KP, Tzinia AK, Mamalaki A, Phelouzat MA, Lawrence F, Robert-Gero M. Expression of the major surface glycoprotein of Leishmania, gp63, in wild-type and sinefungin-resistant promastigotes. EUROPEAN JOURNAL OF BIOCHEMISTRY 1994; 223:61-8. [PMID: 8033909 DOI: 10.1111/j.1432-1033.1994.tb18966.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In this study, we have surveyed gp63 expression in sinefungin-(SF)-resistant and wild-type Leishmania promastigotes. Documentation of gp63 expression in Leishmania promastigotes was carried out by Western blotting, purification of the protein and assessment of gp63 protease activity. We demonstrated a 3-4-fold and 1.5-2-fold increase of gp63 protein in SF-resistant Leishmania donovani and Leishmania tropica promastigotes compared to wild-type, respectively. Northern blot analysis showed that the increase in the amount of gp63 protein in SF-resistant compared to wild-type parasites was concomitant with an increase in gp63 mRNA. No extrachromosomal DNA was identified by alkaline lysis of isolated DNA samples and Southern blot analysis. Treatment of SF-resistant and wild-type L. donovani promastigotes with cycloheximide resulted in an increase of the steady state levels of gp63 mRNA in the SF-resistant parasites to approximately fivefold that of the wild type. After treating parasites with actinomycin D, estimated gp63 mRNA t1/2 in the wild type was 40 min and increased to 83 min in SF-resistant promastigotes. Therefore, the overexpression of gp63 may be mediated, at least in part, by post-transcriptional stabilization of a gp63 transcript by a protein factor. Down regulation of the latter factor may account for the observed increase in gp63 expression in SF-resistant promastigotes. Attempts to correlate gp63 expression with promastigote virulence suggested that the observed increase in gp63 expression did not result in a significant change in the virulence of SF-resistant compared to wild-type L. donovani promastigotes.
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Affiliation(s)
- K P Soteriadou
- Department of Biochemistry, Hellenic Pasteur Institute, Athens, Greece
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Fournet A, Barrios AA, Muñoz V, Hocquemiller R, Roblot F, Cavé A, Richomme P, Bruneton J. Antiprotozoal activity of quinoline alkaloids isolated fromGalipea longiflora, a Bolivian plant used as a treatment for cutaneous leishmaniasis. Phytother Res 1994. [DOI: 10.1002/ptr.2650080312] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Lawrence F, Robert-Gero M. Distribution of macromolecular methylations in promastigotes of Leishmania donovani and impact of sinefungin. J Eukaryot Microbiol 1993; 40:581-9. [PMID: 8401471 DOI: 10.1111/j.1550-7408.1993.tb06111.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Sinefungin, an antifungal and antiparasitic nucleoside antibiotic, is a very potent antileishmanial agent both in vitro and in vivo. This molecule, structurally related to S-adenosylmethionine, is a good competitive inhibitor of methyltransferases in vitro. The aim of this report is to analyze the impact of sinefungin on methylation pattern and the subcellular localisation of methyl groups and various methylases in promastigotes of Leishmania donovani. We have shown the presence of various methylated macromolecules in different subcellular fractions, with somewhat higher concentration in membrane fraction. In vitro, sinefungin inhibits the three main protein methylases, but in cells cultured in its presence the protein carboxylmethylations are specifically inhibited.
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Affiliation(s)
- F Lawrence
- Centre National de la Recherche Scientifique, Institut de Chimie des Substances Naturelles, Gif-sur Yvette, France
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Fournet A, Barrios AA, Muñoz V, Hocquemiller R, Cavé A. Effect of some bisbenzylisoquinoline alkaloids on AmericanLeishmania sp. in BALB/c mice. Phytother Res 1993. [DOI: 10.1002/ptr.2650070404] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Fournet A, Barrios AA, Muñoz V, Hocquemiller R, Cavé A, Bruneton J. 2-substituted quinoline alkaloids as potential antileishmanial drugs. Antimicrob Agents Chemother 1993; 37:859-63. [PMID: 8494383 PMCID: PMC187784 DOI: 10.1128/aac.37.4.859] [Citation(s) in RCA: 116] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Ten 2-substituted quinoline alkaloids isolated from a plant used for treatment of New World cutaneous leishmaniasis have antileishmanial in vitro activities against the extracellular forms of Leishmania spp. BALB/c mice infected with Leishmania amazonensis PH8 or H-142 or Leishmania venezuelensis were treated 1 day after the parasitic infection with a quinoline alkaloid (100 mg/kg of body weight per day) or with reference drug N-methylglucamine antimonate (Glucantime) (56 mg of pentavalent antimony [Sbv] per kg per day) for 14 days. Lesion development was the criterium used to assess disease severity. Two three-carbon chain quinolines [2-n-propylquinoline and 2-(1',2'-trans-epoxypropyl)quinoline (chimanine D)] were more potent than N-methylglucamine antimonate against L. amazonensis PH8, and five quinoline alkaloids [2-(3,4-methylenedioxyphenylethyl)quinoline, cusparine, 2-(3,4-dimethoxyphenylethyl)quinoline, 2-(E)-prop-1'-enylquinoline (chimanine B), and skimmianine] were as effective as the reference drug. Single treatment near the site of infection, 14 days after infection with L. amazonensis, with 2-n-propylquinoline or chimanine B reduced the severity of lesions but less notably than N-methylglucamine antimonate. 2-n-Propylquinoline exhibited significant activity against the virulent strain L. venezuelensis. The active products did not show any apparent toxicities during the experiment. This study is, to our knowledge, the first to show the activity of 2-substituted quinoline alkaloids for experimental treatment of New World cutaneous leishmaniasis. Further investigations of these compounds might yet prove helpful for the development of new antileishmanial drugs.
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Affiliation(s)
- A Fournet
- Département Santé, ORSTOM (Institut Français de Recherche Scientifique pour le Développement en Coopération), Paris, France
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