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Nanoassemblies from Amphiphilic Sb Complexes Target Infection Sites in Models of Visceral and Cutaneous Leishmaniases. Pharmaceutics 2022; 14:pharmaceutics14081743. [PMID: 36015369 PMCID: PMC9412331 DOI: 10.3390/pharmaceutics14081743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/11/2022] [Accepted: 08/19/2022] [Indexed: 11/27/2022] Open
Abstract
This work aims to evaluate whether nanoassemblies (NanoSb) made from antimony(V) complexes with octanoyl-N-methylglucamide (SbL8) or decanoyl-N-methylglucamide (SbL10) would effectively target the infection sites in visceral and cutaneous leishmaniases (VL and CL). NanoSb were investigated regarding stability at different pHs, accumulation of Sb in the macrophage host cell and liver, and in vitro and in vivo activities in models of leishmaniasis. The kinetic stability assay showed that NanoSb are stable at neutral pH, but release incorporated lipophilic substance after conformational change in media that mimic the gastric fluid and the parasitophorous vacuole. NanoSb promoted greater accumulation of Sb in macrophages and in the liver of mice after parenteral administration, when compared to conventional antimonial Glucantime®. SbL10 was much more active than Glucantime® against intramacrophage Leishmania amastigotes and less cytotoxic than SbL8 against macrophages. The in vitro SbL10 activity was further enhanced with co-incorporated miltefosine. NanoSb showed high antileishmanial activity in the L. donovani murine VL after parenteral administration and moderate activity in the L. amazonensis murine CL after topical treatment. This study supports the ability of NanoSb to effectively deliver a combination of Sb and co-incorporated drug to host cell and infected tissues, in a better way than Glucantime® does.
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Periferakis A, Caruntu A, Periferakis AT, Scheau AE, Badarau IA, Caruntu C, Scheau C. Availability, Toxicology and Medical Significance of Antimony. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19084669. [PMID: 35457536 PMCID: PMC9030621 DOI: 10.3390/ijerph19084669] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/04/2022] [Accepted: 04/10/2022] [Indexed: 01/01/2023]
Abstract
Antimony has been known and used since ancient times, but its applications have increased significantly during the last two centuries. Aside from its few medical applications, it also has industrial applications, acting as a flame retardant and a catalyst. Geologically, native antimony is rare, and it is mostly found in sulfide ores. The main ore minerals of antimony are antimonite and jamesonite. The extensive mining and use of antimony have led to its introduction into the biosphere, where it can be hazardous, depending on its bioavailability and absorption. Detailed studies exist both from active and abandoned mining sites, and from urban settings, which document the environmental impact of antimony pollution and its impact on human physiology. Despite its evident and pronounced toxicity, it has also been used in some drugs, initially tartar emetics and subsequently antimonials. The latter are used to treat tropical diseases and their therapeutic potential for leishmaniasis means that they will not be soon phased out, despite the fact the antimonial resistance is beginning to be documented. The mechanisms by which antimony is introduced into human cells and subsequently excreted are still the subject of research; their elucidation will enable us to better understand antimony toxicity and, hopefully, to improve the nature and delivery method of antimonial drugs.
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Affiliation(s)
- Argyrios Periferakis
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania; (A.P.); (A.-T.P.); (I.A.B.); (C.C.)
- Akadimia of Ancient Greek and Traditional Chinese Medicine, 16675 Athens, Greece
| | - Ana Caruntu
- Department of Oral and Maxillofacial Surgery, The “Carol Davila” Central Military Emergency Hospital, 010825 Bucharest, Romania
- Department of Oral and Maxillofacial Surgery, Faculty of Dental Medicine, “Titu Maiorescu” University, 031593 Bucharest, Romania
- Correspondence: (A.C.); (C.S.)
| | - Aristodemos-Theodoros Periferakis
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania; (A.P.); (A.-T.P.); (I.A.B.); (C.C.)
| | - Andreea-Elena Scheau
- Department of Radiology and Medical Imaging, Fundeni Clinical Institute, 022328 Bucharest, Romania;
| | - Ioana Anca Badarau
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania; (A.P.); (A.-T.P.); (I.A.B.); (C.C.)
| | - Constantin Caruntu
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania; (A.P.); (A.-T.P.); (I.A.B.); (C.C.)
- Department of Dermatology, Prof. N.C. Paulescu National Institute of Diabetes, Nutrition and Metabolic Diseases, 011233 Bucharest, Romania
| | - Cristian Scheau
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania; (A.P.); (A.-T.P.); (I.A.B.); (C.C.)
- Correspondence: (A.C.); (C.S.)
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Seif MA, Al-Mohammed HI. ASSESSMENT OF THE OXIDATIVE AND NITROSATIVE STRESS IN THE SERUM OF SAUDI PATIENTS WITH CUTANEOUS LEISHMANIASIS BEFORE AND AFTER TREATMENT. J Parasitol 2021; 107:810-816. [PMID: 34648629 DOI: 10.1645/20-109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Macrophages, within which Leishmania species replicate, generate large amounts of reactive oxygen species (ROS) and reactive nitrogen species (RNS) to kill these parasites. The present study assessed the oxidative and nitrosative stress, and specific immune enzymes in the serum of patients with cutaneous leishmaniasis (Cl) before and after treatment and in the control individuals. Serum activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), L-arginase, myeloperoxidase (MPO), and adenosine deaminase (ADA) and the levels of reduced glutathione, malondialdehyde (MDA), and nitric oxide (NO) were studied. The activities of L-arginase, MPO, and ADA and the levels of MDA and NO were significantly elevated (P < 0.001), while the activities of SOD, CAT, and GSH-Px, and the levels of reduced glutathione (GSH) were significantly (P < 0.001) reduced in untreated patients as compared with values of patients after treatment and of control individuals. The treatment, which included intramuscular injection of sodium stibogluconate and meglumine antimoniate, ameliorated these factors in comparison to the untreated group. These results suggest that oxidative and nitrosative stress may play an important role in the pathogenesis of untreated cutaneous leishmaniasis. Furthermore, the reduction in oxidative and nitrosative stress in the treated Cl patients may be due to the drug decreasing energy production by the parasite, which eventually leads to its death.
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Affiliation(s)
- Mossad A Seif
- Division of Biochemistry, Biomedical Sciences Department, College of Medicine, King Faisal University, P.O. Box 10950, Hufof, Al-Ahsa, 31982, Kingdom of Saudi Arabia
| | - Hamdan I Al-Mohammed
- Division of Parasitology, Biomedical Sciences Department, College of Medicine, King Faisal University, P.O. Box 10950, Hufof, Al-Ahsa, 31982, Kingdom of Saudi Arabia
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Strike a Balance: Between Metals and Non-Metals, Metalloids as a Source of Anti-Infective Agents. INORGANICS 2021. [DOI: 10.3390/inorganics9060046] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Most of the commercially available anti-infective agents are organic molecules. In fact, though, during the pioneering times of modern medicine, at the beginning of the 20th century, several inorganic compounds of transition metals were used for medicinal application, to date, only a small number of inorganic drugs are used in clinical practice. Beyond the transition metals, metalloids—or semimetals—offer a rich chemistry in between that of metallic and non-metallic elements, and accordingly, peculiar features for their exploitation in medicinal chemistry. A few important examples of metalloid-based drugs currently used for the treatment of various diseases do exist. However, the use of this group of elements could be further expanded on the basis of their current applications and the clinical trials they entered. Considering that metalloids offer the opportunity to expand the “chemical-space” for developing novel anti-infective drugs and protocols, in this paper, we briefly recapitulate and discuss the current applications of B-, Si-, As-, Sb- and Te-based anti-infective drugs.
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García-Bustos MF, Moya Álvarez A, Pérez Brandan C, Parodi C, Sosa AM, Buttazzoni Zuñiga VC, Pastrana OM, Manghera P, Peñalva PA, Marco JD, Barroso PA. Development of a Fluorescent Assay to Search New Drugs Using Stable tdTomato- Leishmania, and the Selection of Galangin as a Candidate With Anti-Leishmanial Activity. Front Cell Infect Microbiol 2021; 11:666746. [PMID: 34150675 PMCID: PMC8213385 DOI: 10.3389/fcimb.2021.666746] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 05/17/2021] [Indexed: 12/03/2022] Open
Abstract
Antimonials continue to be considered the first-line treatment for leishmaniases, but its use entails a wide range of side effects and serious reactions. The search of new drugs requires the development of methods more sensitive and faster than the conventional ones. We developed and validated a fluorescence assay based in the expression of tdTomato protein by Leishmania, and we applied this method to evaluate the activity in vitro of flavonoids and reference drugs. The pIR1SAT/tdTomato was constructed and integrated into the genome of Leishmania (Leishmania) amazonensis. Parasites were selected with nourseothricin (NTC). The relation of L. amaz/tc3 fluorescence and the number of parasites was determined; then the growth in vitro and infectivity in BALB/c mice was characterized. To validate the fluorescence assay, the efficacy of miltefosine and meglumine antimoniate was compared with the conventional methods. After that, the method was used to assess in vitro the activity of flavonoids; and the mechanism of action of the most active compound was evaluated by transmission electron microscopy and ELISA. A linear correlation was observed between the emission of fluorescence of L. amaz/tc3 and the number of parasites (r2 = 0.98), and the fluorescence was stable in the absence of NTC. No differences were observed in terms of infectivity between L. amaz/tc3 and wild strain. The efficacy of miltefosine and meglumine antimoniate determined by the fluorescence assay and the microscopic test showed no differences, however, in vivo the fluorescence assay was more sensitive than limiting dilution assay. Screening assay revealed that the flavonoid galangin (GAL) was the most active compound with IC50 values of 53.09 µM and 20.59 µM in promastigotes and intracellular amastigotes, respectively. Furthermore, GAL induced mitochondrial swelling, lipid inclusion bodies and vacuolization in promastigotes; and up-modulated the production of IL-12 p70 in infected macrophages. The fluorescence assay is a useful tool to assess the anti-leishmanial activity of new compounds. However, the assay has some limitations in the macrophage-amastigote model that might be related with an interfere of flavanol aglycones with the fluorescence readout of tdTomato. Finally, GAL is a promising candidate for the development of new treatment against the leishmaniasis.
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Affiliation(s)
- María Fernanda García-Bustos
- Escuela Universitaria en Ciencias de la Salud y Facultad de Ciencias Agrarias y Veterinarias, Universidad Católica de Salta, Salta, Argentina
- Instituto de Patología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad Nacional de Salta, Salta, Argentina
- Facultad de Ciencias de la Salud, Universidad Nacional de Salta, Salta, Argentina
| | - Agustín Moya Álvarez
- Instituto de Patología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad Nacional de Salta, Salta, Argentina
| | - Cecilia Pérez Brandan
- Instituto de Patología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad Nacional de Salta, Salta, Argentina
| | - Cecilia Parodi
- Instituto de Patología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad Nacional de Salta, Salta, Argentina
| | - Andrea Mabel Sosa
- Instituto de Patología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad Nacional de Salta, Salta, Argentina
| | - Valeria Carolina Buttazzoni Zuñiga
- Escuela Universitaria en Ciencias de la Salud y Facultad de Ciencias Agrarias y Veterinarias, Universidad Católica de Salta, Salta, Argentina
| | - Oscar Marcelo Pastrana
- Escuela Universitaria en Ciencias de la Salud y Facultad de Ciencias Agrarias y Veterinarias, Universidad Católica de Salta, Salta, Argentina
| | - Paula Manghera
- Escuela Universitaria en Ciencias de la Salud y Facultad de Ciencias Agrarias y Veterinarias, Universidad Católica de Salta, Salta, Argentina
| | - Pablo Alejandro Peñalva
- Escuela Universitaria en Ciencias de la Salud y Facultad de Ciencias Agrarias y Veterinarias, Universidad Católica de Salta, Salta, Argentina
| | - Jorge Diego Marco
- Instituto de Patología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad Nacional de Salta, Salta, Argentina
| | - Paola Andrea Barroso
- Instituto de Patología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad Nacional de Salta, Salta, Argentina
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The thiol-based reduction of Bi(V) and Sb(V) anti-leishmanial complexes. J Inorg Biochem 2021; 221:111470. [PMID: 33971522 DOI: 10.1016/j.jinorgbio.2021.111470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 04/07/2021] [Accepted: 04/24/2021] [Indexed: 01/22/2023]
Abstract
Low molecular weight thiols including trypanothione and glutathione play an important function in the cellular growth, maintenance and reduction of oxidative stress in Leishmania species. In particular, parasite specific trypanothione has been established as a prime target for new anti-leishmania drugs. Previous studies into the interaction of the front-line Sb(V) based anti-leishmanial drug meglumine antimoniate with glutathione, have demonstrated that a reduction pathway may be responsible for its effective and selective nature. The new suite of organometallic complexes, of general formula [MAr3(O2CR)2] (M = Sb or Bi) have been shown to have potential as new selective drug candidates. However, their behaviour towards the critical thiols glutathione and trypanothione is still largely unknown. Using NMR spectroscopy and mass spectrometry we have examined the interaction of the analogous Sb(V) and Bi(V) organometallic complexes, [SbPh3(O2CCH2(C6H4CH3))2] S1 and [BiPh3(O2CCH2(C6H4CH3))2] B1, with the trifluoroacetate (TFA) salt of trypanothione and L-glutathione. In the presence of trypanothione or glutathione at the clinically relevant pH of 4-5 for Leishmania amastigotes, both complexes undergo facile and rapid reduction, with no discernible difference. However, at a higher pH (6-7), the complexes behave quite differently towards glutathione. The Bi(V) complex is again reduced rapidly but the Sb(V) complex undergoes slow reduction over 8 h (t1/2 = 54 min.) These results give the first insights into why the highly oxidising Bi(V) complexes display low selectivity in their cytotoxicity towards leishmanial and mammalian cells, while the Sb(V) complexes show good selectivity.
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Dong QY, Fang YC, Tan B, Ontiveros-Valencia A, Li A, Zhao HP. Antimonate removal by diatomite modified with Fe-Mn oxides: application and mechanism study. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:13873-13885. [PMID: 33201506 DOI: 10.1007/s11356-020-11592-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 11/09/2020] [Indexed: 06/11/2023]
Abstract
In this study, diatomite coated with Fe-Mn oxides (DFMO) was synthesized through calcination. The adsorption of antimonate (Sb(V)) by DFMO was studied, and environmental factors affecting the adsorption were investigated. The components of DFMO were identified as γ-Fe2O3, γ-MnO2, and SiO2, in the presence of diatomite covered with nanoscale metal oxides. Batch experiments were carried out to evaluate the antimonate adsorption performance in aqueous solution. Results showed that maximum Sb(V) adsorption capacity of DFMO reached 10.7 mg/g at pH 4, corresponding to 22.2 mg/g per unit metal oxides. Antimonate adsorption occurred on heterogenous surface, following the Freundlich and Pseudo-second order model. Overall, antimonate adsorption was favored at acidic condition due to low point of zero charge. However, when treating electroplating wastewater, neutral pH condition exhibited a higher efficiency than acidic pH, because co-existing ions in electroplating wastewater significantly affects antimony adsorption. Further investigation showed that among different potential co-existing ions, fluoride can strongly inhibit the adsorption of antimonate at 5 mg/L under pH 4. Density functional theory (DFT) analysis confirmed that adsorption energy on DFMO follows: HF < F- < Sb(OH)6-, indicating that fluoride is easier to bind with DFMO compared to antimonate, especially under pH 3.5 at which fluoride exists as HF. Moreover, the competitive adsorption of fluoride toward antimonate indicated the necessity of pre-treatment like neutralization and precipitation before adsorption process.
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Affiliation(s)
- Qiu-Yi Dong
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Prov Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yu-Chun Fang
- Hangzhou Shangtuo Environmental Technology Co.,LTD, Hangzhou, Zhejiang, China
| | - Bin Tan
- Hangzhou Shangtuo Environmental Technology Co.,LTD, Hangzhou, Zhejiang, China
| | - Aura Ontiveros-Valencia
- Division de Ciencias Ambientales, Instituto Potosino de Investigacion Cientifica y Tecnologica, San Luis Potosi, Mexico
| | - Ang Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - He-Ping Zhao
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China.
- Zhejiang Prov Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China.
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In vitro and in vivo anti-parasitic activity of biogenic antimony sulfide nanoparticles on Leishmania major (MRHO/IR/75/ER). Parasitol Res 2019; 118:2669-2678. [DOI: 10.1007/s00436-019-06382-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 06/21/2019] [Indexed: 10/26/2022]
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Borborema SET, Osso JA, de Andrade HF, do Nascimento N. Pharmacokinetics of neutron-irradiated meglumine antimoniate in Leishmania amazonensis-infected BALB/c mice. J Venom Anim Toxins Incl Trop Dis 2019; 25:e144618. [PMID: 31130998 PMCID: PMC6521709 DOI: 10.1590/1678-9199-jvatitd-1446-18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 10/17/2018] [Indexed: 11/21/2022] Open
Abstract
Background Cutaneous leishmaniasis (CL) is a parasitic disease caused by the protozoan Leishmania spp. Pentavalent antimonial agents have been used as an effective therapy, despite their side effects and resistant cases. Their pharmacokinetics remain largely unexplored. This study aimed to investigate the pharmacokinetic profile of meglumine antimoniate in a murine model of cutaneous leishmaniasis using a radiotracer approach. Methods Meglumine antimoniate was neutron-irradiated inside a nuclear reactor and was administered once intraperitoneally to uninfected and L. amazonensis-infected BALB/c mice. Different organs and tissues were collected and the total antimony was measured. Results Higher antimony levels were found in infected than uninfected footpad (0.29% IA vs. 0.14% IA, p = 0.0057) and maintained the concentration. The animals accumulated and retained antimony in the liver, which cleared slowly. The kidney and intestinal uptake data support the hypothesis that antimony has two elimination pathways, first through renal excretion, followed by biliary excretion. Both processes demonstrated a biphasic elimination profile classified as fast and slow. In the blood, antimony followed a biexponential open model. Infected mice showed a lower maximum concentration (6.2% IA/mL vs. 11.8% IA/mL, p = 0.0001), a 2.5-fold smaller area under the curve, a 2.7-fold reduction in the mean residence time, and a 2.5-fold higher clearance rate when compared to the uninfected mice. Conclusions neutron-irradiated meglumine antimoniate concentrates in infected footpad, while the infection affects antimony pharmacokinetics.
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Affiliation(s)
- Samanta Etel Treiger Borborema
- Center for Biotechnology, Nuclear and Energy Research Institute, São Paulo, SP, Brazil.,Center for Parasitology and Mycology, Adolfo Lutz Institute, São Paulo, SP, Brazil
| | - João Alberto Osso
- Center for Radiopharmacy, Nuclear and Energy Research Institute, São Paulo, SP, Brazil
| | - Heitor Franco de Andrade
- Laboratory of Protozoology, São Paulo Tropical Medicine Institute, University of São Paulo (IMTSP/USP) São Paulo, SP, Brazil
| | - Nanci do Nascimento
- Center for Biotechnology, Nuclear and Energy Research Institute, São Paulo, SP, Brazil
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Transport and detoxification of metalloids in plants in relation to plant-metalloid tolerance. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.plgene.2019.100171] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Borborema SET, Osso Junior JA, Tempone AG, de Andrade Junior HF, do Nascimento N. Pharmacokinetic of meglumine antimoniate encapsulated in phosphatidylserine-liposomes in mice model: A candidate formulation for visceral leishmaniasis. Biomed Pharmacother 2018; 103:1609-1616. [DOI: 10.1016/j.biopha.2018.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 04/12/2018] [Accepted: 05/02/2018] [Indexed: 01/15/2023] Open
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Synthesis of heteroleptic pentavalent antimonials bearing heterocyclic cinnamate moieties and their biological studies. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.02.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Saheki MN, Lyra MR, Bedoya-Pacheco SJ, Antônio LDF, Pimentel MIF, Salgueiro MDM, Vasconcellos ÉDCFE, Passos SRL, dos Santos GPL, Ribeiro MN, Fagundes A, Madeira MDF, Mouta-Confort E, Marzochi MCDA, Valete-Rosalino CM, Schubach ADO. Low versus high dose of antimony for American cutaneous leishmaniasis: A randomized controlled blind non-inferiority trial in Rio de Janeiro, Brazil. PLoS One 2017; 12:e0178592. [PMID: 28558061 PMCID: PMC5448803 DOI: 10.1371/journal.pone.0178592] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 05/12/2017] [Indexed: 11/18/2022] Open
Abstract
Background Although high dose of antimony is the mainstay for treatment of American cutaneous leishmaniasis (ACL), ongoing major concerns remain over its toxicity. Whether or not low dose antimony regimens provide non-inferior effectiveness and lower toxicity has long been a question of dispute. Methods A single-blind, non-inferiority, randomized controlled trial was conducted comparing high dose with low dose of antimony in subjects with ACL treated at a referral center in Rio de Janeiro, an endemic area of Leishmania (Viannia) braziliensis transmission. The primary outcome was clinical cure at 360 days of follow-up in the modified-intention-to-treat (mITT) and per-protocol (PP) populations. Non-inferiority margin was 15%. Secondary objectives included occurrence of epithelialization, adverse events and drug discontinuations. This study was registered in ClinicalTrials.gov: NCT01301924. Results Overall, 72 patients were randomly assigned to one of the two treatment arms during October 2008 to July 2014. In mITT, clinical cure was observed in 77.8% of subjects in the low dose antimony group and 94.4% in the high dose antimony group after one series of treatment (risk difference 16.7%; 90% CI, 3.7–29.7). The results were confirmed in PP analysis, with 77.8% of subjects with clinical cure in the low dose antimony group and 97.1% in the high dose antimony group (risk difference 19.4%; 90% CI, 7.1–31.7). The upper limit of the confidence interval exceeded the 15% threshold and was also above zero supporting the hypothesis that low dose is inferior to high dose of antimony after one series of treatment. Nevertheless, more major adverse events, a greater number of adverse events and major adverse events per subject, and more drug discontinuations were observed in the high dose antimony group (all p<0.05). Interestingly, of all the subjects who were originally allocated to the low dose antimony group and were followed up after clinical failure, 85.7% achieved cure after a further treatment with local therapy or low dose of antimony. Conclusions Compared with high dose, low dose of antimony was inferior at the pre-specified margin after one series of treatment of ACL, but was associated with a significantly lower toxicity. While high dose of antimony should remain the standard treatment for ACL, low dose antimony treatment might be preferred when toxicity is a primary concern.
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Affiliation(s)
- Mauricio Naoto Saheki
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
- * E-mail:
| | - Marcelo Rosandiski Lyra
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Sandro Javier Bedoya-Pacheco
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
- Department of Epidemiology and Quantitative Methods in Health, Sergio Arouca National School of Public Health, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Liliane de Fátima Antônio
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Maria Inês Fernandes Pimentel
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Mariza de Matos Salgueiro
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Érica de Camargo Ferreira e Vasconcellos
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Sonia Regina Lambert Passos
- Clinical Epidemiology Laboratory, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Ginelza Peres Lima dos Santos
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Madelon Novato Ribeiro
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Aline Fagundes
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Maria de Fátima Madeira
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Eliame Mouta-Confort
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Mauro Célio de Almeida Marzochi
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
| | - Cláudia Maria Valete-Rosalino
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
- Department of Otorhinolaryngology and Ophthalmology, Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Armando de Oliveira Schubach
- Laboratory for Leishmaniasis Surveillance, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro State, Brazil
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Ravinder R, Goyal N. Cloning, characterization and subcellular localization of Nuclear LIM interactor interacting factor gene from Leishmania donovani. Gene 2017; 611:1-8. [DOI: 10.1016/j.gene.2017.02.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 02/04/2017] [Accepted: 02/06/2017] [Indexed: 12/30/2022]
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15
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Singh N, Sundar S. Integrating genomics and proteomics permits identification of immunodominant antigens associated with drug resistance in human visceral leishmaniasis in India. Exp Parasitol 2017; 176:30-45. [PMID: 28263760 DOI: 10.1016/j.exppara.2017.02.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/04/2017] [Accepted: 02/25/2017] [Indexed: 12/24/2022]
Abstract
Resistance of human pathogens like Leishmania to drugs is a growing concern where the multidrug-resistant phenotype renders chemotherapy ineffective. The acquired resistance of Leishmania to antimony has promoted intense research on the mechanisms involved but the question has not been resolved yet. In this study we have explored host-pathogen- drug interactions leading to identification of pharmacological determinants of host macrophages that resist the sodium antimony gluconate (SAG) mediated intracellular parasite killing. mRNA profiling of mammalian host stage amastigotes of sodium antimony gluconate (SAG) 'sensitive' and 'resistant' parasite lines was carried out using Affymetrix GeneChip® Human Genome U133 Plus 2.0 Array. Patient sera was used to identify immunogenic proteins by two-dimensional gel analysis (2DE) and mass spectrometric analysis (LC-MS/MS). Immunofluorescence microscopy confirmed the identities on 'sensitive' and 'resistant' parasite lines. A total of nine immunogenic proteins whose intensities changed significantly and consistently in multiple experiments were detected, suggesting that a cohort of proteins are altered in expression levels in the 'resistant' parasites. Global expression profiling using microarrays revealed this regulation was not reflected by changes in the levels of the cognate mRNAs. Following identification of proteins by mass spectrometry, one such regulated protein, enolase, was chosen for more detailed analysis. Immunofluorescence microscopy employing antisera against this enzyme confirmed that its level was differentially regulated in the 'resistant' isolate. We show that high serum level of immunoreactive protein is associated with 'resistant' phenotype. Differentially expressed proteins with immunomodulatory activities were found to be associated with the 'resistant phenotype'.
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Affiliation(s)
- Neeloo Singh
- Biochemistry Division, CSIR-Central Drug Research Institute, B 10/1, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, India.
| | - Shyam Sundar
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221 005, India.
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16
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Borborema SET, Osso Junior JA, Andrade Junior HFD, Nascimento ND. Antimonial drugs entrapped into phosphatidylserine liposomes: physicochemical evaluation and antileishmanial activity. Rev Soc Bras Med Trop 2016; 49:196-203. [DOI: 10.1590/0037-8682-0041-2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 04/13/2016] [Indexed: 01/09/2023] Open
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17
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Murray HW, Mitchell-Flack M, Taylor GA, Ma X. IFN-γ-induced macrophage antileishmanial mechanisms in mice: A role for immunity-related GTPases, Irgm1 and Irgm3, in Leishmania donovani infection in the liver. Exp Parasitol 2015; 157:103-9. [PMID: 26208780 PMCID: PMC4640457 DOI: 10.1016/j.exppara.2015.07.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 07/14/2015] [Accepted: 07/19/2015] [Indexed: 12/14/2022]
Abstract
In C57BL/6 mice, Leishmania donovani infection in the liver provoked IFN-γ-induced expression of the immunity-related GTPases (IRG), Irgm1 and Irgm3. To gauge the antileishmanial effects of these macrophage factors in the liver, intracellular infection was analyzed in IRG-deficient mice. In early- (but not late-) stage infection, Irgm3(-/-) mice failed to properly control parasite replication, generated little tissue inflammation and were hyporesponsive to pentavalent antimony (Sb) chemotherapy. Observations limited to early-stage infection in Irgm1(-/-) mice demonstrated increased susceptibility and virtually no inflammatory cell recruitment to heavily-parasitized parenchymal foci but an intact response to chemotherapy. In L. donovani infection in the liver, the absence of either Irgm1 or Irgm3 impairs early inflammation and initial resistance; the absence of Irgm3, but not Irgm1, also appears to impair the intracellular efficacy of Sb chemotherapy.
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Affiliation(s)
- Henry W Murray
- Department of Medicine, Weill Cornell Medical College, New York, NY, USA.
| | | | - Gregory A Taylor
- Departments of Medicine, Molecular Genetics and Microbiology and Immunology, Division of Geriatrics and Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, NC, USA; Geriatric Research, Education and Clinical Center, VA Medical Center, Durham, NC, USA
| | - Xiaojing Ma
- Shanghai Jiaotong University, School of Life Science and Biotechnology, Shanghai, China; Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, USA
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18
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Alvarenga BM, Melo MN, Frézard F, Demicheli C, Gomes JMM, Borba da Silva JB, Speziali NL, Corrêa Junior JD. Nanoparticle phosphate-based composites as vehicles for antimony delivery to macrophages: possible use in leishmaniasis. J Mater Chem B 2015; 3:9250-9259. [DOI: 10.1039/c5tb00376h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nontoxic NPC containing Sb(v) boosts the infected macrophage recovery.
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Affiliation(s)
- Betânia Mara Alvarenga
- Departamento de Morfologia
- Instituto de Ciências Biológicas
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - Maria Norma Melo
- Departamento de Parasitologia
- Instituto de Ciências Biológicas
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - Fréderic Frézard
- Departamento de Fisiologia e Biofísica
- Instituto de Ciências Biológicas
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - Cynthia Demicheli
- Departamento de Química
- Instituto de Ciências Exatas
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - Juliana Moreira Mendonça Gomes
- Departamento de Morfologia
- Instituto de Ciências Biológicas
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - José Bento Borba da Silva
- Departamento de Química
- Instituto de Ciências Exatas
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - Nivaldo Lucio Speziali
- Departamento de Física
- Instituto de Ciências Exatas
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - José Dias Corrêa Junior
- Departamento de Morfologia
- Instituto de Ciências Biológicas
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
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Design, structural and spectroscopic elucidation of new nitroaromatic carboxylic acids and semicarbazones for the in vitro screening of anti-leishmanial activity. J Mol Struct 2015. [DOI: 10.1016/j.molstruc.2014.08.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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20
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Borborema SET, Osso JA, Andrade HFD, Nascimento ND. Biodistribution of meglumine antimoniate in healthy and Leishmania (Leishmania) infantum chagasi-infected BALB/c mice. Mem Inst Oswaldo Cruz 2014; 108:623-30. [PMID: 23903979 PMCID: PMC3970594 DOI: 10.1590/0074-0276108052013014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 05/28/2013] [Indexed: 11/29/2022] Open
Abstract
Pentavalent antimonials such as meglumine antimoniate (MA) are the
primary treatments for leishmaniasis, a complex disease caused by protozoan
parasites of the genus Leishmania . Despite over 70 years of
clinical use, their mechanisms of action, toxicity and pharmacokinetics have not
been fully elucidated. Radiotracer studies performed on animals have the
potential to play a major role in pharmaceutical development. The aims of this
study were to prepare an antimony radiotracer by neutron irradiation of MA and
to determine the biodistribution of MA in healthy and Leishmania
(Leishmania) infantum chagasi-infected mice. MA
(Glucantime(r)) was neutron irradiated inside the IEA-R1 nuclear
reactor, producing two radioisotopes, 122Sb and 124Sb, with high radionuclidic
purity and good specific activity. This irradiated compound presented
anti-leishmanial activity similar to that of non-irradiated MA in both in vitro
and in vivo evaluations. In the biodistribution studies, healthy mice showed
higher uptake of antimony in the liver than infected mice and elimination
occurred primarily through biliary excretion, with a small proportion of the
drug excreted by the kidneys. The serum kinetic curve was bi-exponential, with
two compartments: the central compartment and another compartment associated
with drug excretion. Radiotracers, which can be easily produced by neutron
irradiation, were demonstrated to be an interesting tool for answering several
questions regarding antimonial pharmacokinetics and chemotherapy.
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Affiliation(s)
- Samanta Etel Treiger Borborema
- Centro de Biotecnologia, Instituto de Pesquisas Energéticas e Nucleares, Comissão Nacional de Energia Nuclear, São Paulo, SP, Brasil.
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Ribeiro MN, Pimentel MIF, Schubach ADO, Oliveira RDVCD, Teixeira JL, Leite MPDS, Fonseca M, Santos GPLD, Salgueiro MM, Ferreira e Vasconcellos EDC, Lyra MR, Saheki MN, Valete-Rosalino CM. Factors associated to adherence to different treatment schemes with meglumine antimoniate in a clinical trial for cutaneous leishmaniasis. Rev Inst Med Trop Sao Paulo 2014; 56:291-6. [PMID: 25076428 PMCID: PMC4131813 DOI: 10.1590/s0036-46652014000400004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 01/10/2014] [Indexed: 11/22/2022] Open
Abstract
The favorable outcome of the treatment of a disease is influenced by the adherence to therapy. Our objective was to assess factors associated with adherence to treatment of patients included in a clinical trial of equivalence between the standard and alternative treatment schemes with meglumine antimoniate (MA) in the treatment of cutaneous leishmaniasis (CL), in the state of Rio de Janeiro. Between 2008 and 2011, 57 patients with CL were interviewed using a questionnaire to collect socioeconomic data. The following methods were used for adherence monitoring: counting of vial surplus, monitoring card, Morisky test and modified Morisky test (without the question regarding the schedule); we observed 82.1% (vial return), 86.0% (monitoring card), 66.7% (Morisky test) and 86.0% (modified Morisky test) adherence. There was a strong correlation between the method of vial counting and the monitoring card and modified Morisky test. A significant association was observed between greater adherence to treatment and low dose of MA, as well as with a lower number of people sleeping in the same room. We recommend the use of the modified Morisky test to assess adherence to treatment of CL with MA, because it is a simple method and with a good performance, when compared to other methods.
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Affiliation(s)
| | | | | | | | | | | | - Monique Fonseca
- Instituto de Pesquisas Evandro Chagas, IPEC/FIOCRUZ, Rio de Janeiro, RJ, Brazil
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22
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Nühs A, Schäfer C, Zander D, Trübe L, Tejera Nevado P, Schmidt S, Arevalo J, Adaui V, Maes L, Dujardin JC, Clos J. A novel marker, ARM58, confers antimony resistance to Leishmania spp. Int J Parasitol Drugs Drug Resist 2014; 4:37-47. [PMID: 24596667 PMCID: PMC3940081 DOI: 10.1016/j.ijpddr.2013.11.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Revised: 11/22/2013] [Accepted: 11/25/2013] [Indexed: 12/22/2022]
Abstract
Protozoa of the Leishmania genus cause a variety of disease forms that rank at the top of the list of neglected tropical diseases. Anti-leishmanial drugs based on pentavalent antimony have been the mainstay of therapy for over 60 years and resistance against them is increasingly encountered in the field. The biochemical basis for this is poorly understood and likely diverse. No stringent correlation between genetic markers and antimony resistance has so far been shown, prompting us to use a functional cloning approach to identify markers of resistance. Using gene libraries derived from drug-resistant and drug-sensitive Leishmania braziliensis clinical isolates in a functional cloning strategy, we repeatedly selected one gene locus located on chromosome 20 whose amplification confers increased antimony (III) resistance in vitro to an otherwise sensitive L. braziliensis clone. The gene responsible for the effect encodes a previously hypothetical protein that we dubbed LbrARM58. It comprises four repeats of a domain of unknown function, DUF1935, one of them harbouring a potential trans-membrane domain. The gene is so far unique to the Leishmania genus, while a structurally related gene without antimony resistance functionality is also found in Trypanosoma spp. Overexpression of LbrARM58 also confers antimony resistance to promastigotes and intracellular amastigotes of the related species Leishmania infantum, indicating a conserved function in Old World and New World Leishmania species. Our results also show that in spite of their RNAi system, L. braziliensis promastigotes can serve as acceptor cells for episomally propagated cosmid libraries, at least for the initial stages of functional cloning efforts.
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Affiliation(s)
- Andrea Nühs
- Bernhard Nocht Institute for Tropical Medicine, D20359 Hamburg, Germany
| | - Carola Schäfer
- Bernhard Nocht Institute for Tropical Medicine, D20359 Hamburg, Germany
| | - Dorothea Zander
- Bernhard Nocht Institute for Tropical Medicine, D20359 Hamburg, Germany
| | - Leona Trübe
- Bernhard Nocht Institute for Tropical Medicine, D20359 Hamburg, Germany
| | | | - Sonja Schmidt
- Bernhard Nocht Institute for Tropical Medicine, D20359 Hamburg, Germany
| | - Jorge Arevalo
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Vanessa Adaui
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Louis Maes
- Department of Biomedical Sciences, Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, University of Antwerp, Antwerp, Belgium
| | - Jean-Claude Dujardin
- Instituut voor Tropische Geneeskunde, Antwerp, Belgium
- Department of Biomedical Sciences, Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, University of Antwerp, Antwerp, Belgium
| | - Joachim Clos
- Bernhard Nocht Institute for Tropical Medicine, D20359 Hamburg, Germany
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23
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Pharmacokinetics of experimental pentavalent antimony after intramuscular administration in adult volunteers. Curr Ther Res Clin Exp 2014; 67:193-203. [PMID: 24678095 DOI: 10.1016/j.curtheres.2006.06.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/04/2006] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Pentavalent antimony (SbV) has demonstrated therapeuticeffectiveness against clinical manifestations of leishmaniasis, an infection caused by Leishmania, a genus of flagellate protozoa comprising parasites of worldwide distribution. Approximately 1.8 million new cases are reported annually. OBJECTIVE The aim of this study was to assess the pharmacokinetics of the investigational generic SbV, Ulamina (pentachloride of antimony + N-methylglucamine), in healthy adult volunteers. METHODS In this study, SbV was administered IM as a single 5-mg/kg dose.Blood samples were collected at 0.25, 0.75, 1, 2, 4, 8, 12, and 24 hours after administration; urine samples were collected at 6-hour intervals during the 24-hour postadministration period. Determination of trivalent antimony, SbV, and total antimony concentrations in blood and urine samples was carried out using atomic absorption spectrometry. Clinical history was reviewed and the subjects were monitored before and after administration of SbV using physical examination, weight, and hepatic- and renal-function studies. The pharmacokinetic parameters calculated were Cmax, Tmax, absorption constant (Ka), elimination constant (Kel), AUC2-24h, AUC0-∞, elimination phase (t½β), volume of distribution (Vd), and urinary excretion rate. RESULTS Five subjects (3 men, 2 women; mean age, 28 years [range, 18-34 years]) were included in the study. One hour after drug administration the following values were obtained: Cmax, 1.1 μg/mL; Tmax, 1.3 hours; Ka, 1.87 hours; Kel, 0.043 hours; AUC0-24h, 12.26 μg/mL · h; AUC0-∞, 19.84 μg/mL · h; t½β, 17.45 hours; Vd, 6.6 L/kg; and urinary excretion rate, 2.8 μg/h; these were mean values for the entire study group. The single dose was well tolerated by all subjects. CONCLUSIONS The investigational generic SbV, Ulamina, was associated with linearelimination after IM administration of a single 5-mg/kg dose. A 2-compartment pharmacokinetic model was observed in these volunteers; the mean t½β, was 17.45 hours and the mean Vd was 6.6 L/kg.
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24
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Mukherjee A, Boisvert S, Monte-Neto RLD, Coelho AC, Raymond F, Mukhopadhyay R, Corbeil J, Ouellette M. Telomeric gene deletion and intrachromosomal amplification in antimony-resistant Leishmania. Mol Microbiol 2013; 88:189-202. [PMID: 23421749 DOI: 10.1111/mmi.12178] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/06/2013] [Indexed: 11/29/2022]
Abstract
Antimonials are still the mainstay of treatment against leishmaniasis but drug resistance is increasing. We carried out short read next-generation sequencing (NGS) and comparative genomic hybridization (CGH) of three independent Leishmania major antimony-resistant mutants. Copy number variations were consistently detected with both NGS and CGH. A major attribute of antimony resistance was a novel terminal deletion of variable length (67 kb to 204 kb) of the polyploid chromosome 31 in the three mutants. Terminal deletions in two mutants occurred at the level of inverted repeated sequences. The AQP1 gene coding for an aquaglyceroporin was part of the deleted region and its transfection into resistant mutants reverted resistance to SbIII. We also highlighted an intrachromosomal amplification of a subtelomeric locus on chromosome 34 in one mutant. This region encoded for ascorbate-dependent peroxidase (APX) and glucose-6-phosphate dehydrogenase (G6PDH). Overexpression of these genes in revertant backgrounds demonstrated resistance to SbIII and protection from reactive oxygen species (ROS). Generation of a G6PDH null mutant in one revertant exhibited SbIII sensitivity and a decreased protection of ROS. Our genomic analyses and functional validation highlighted novel genomic rearrangements, functionally important resistant loci and the implication of new genes in antimony resistance in Leishmania.
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Affiliation(s)
- Angana Mukherjee
- Centre de Recherche en Infectiologie, Université Laval, Québec, Canada, G1V 4G2
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25
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Discovery of factors linked to antimony resistance in Leishmania panamensis through differential proteome analysis. Mol Biochem Parasitol 2012; 183:166-76. [PMID: 22449941 DOI: 10.1016/j.molbiopara.2012.03.002] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 03/05/2012] [Accepted: 03/06/2012] [Indexed: 12/19/2022]
Abstract
The rate of treatment failure to antileishmanial chemotherapy in Latin America is up to 64%. Parasite drug resistance contributes to an unknown proportion of treatment failures. Identification of clinically relevant molecular mechanisms responsible for parasite drug resistance is critical to the conservation of available drugs and to the discovery of novel targets to reverse the resistant phenotype. We conducted comparative proteomic-based analysis of Leishmania (Viannia) panamensis lines selected in vitro for resistance to trivalent antimony (Sb(III)) to identify factors associated with antimony resistance. Using 2-dimensional gel electrophoresis, two distinct sub-proteomes (soluble in NP-40/urea and Triton X-114, respectively) of promastigotes of WT and Sb(III)-resistant lines were generated. Overall, 9 differentially expressed putative Sb-resistance factors were detected and identified by mass spectrometry. These constituted two major groups: (a) proteins involved in general stress responses and (b) proteins with highly specific metabolic and transport functions, potentially directly contributing to the Sb-resistance mechanism. Notably, the sulfur amino acid-metabolizing enzymes S-adenosylmethionine synthetase (SAMS) and S-adenosylhomocysteine hydrolase (SAHH) were over-expressed in Sb(III)-resistant lines and Sb(III)-resistant clinical isolates. These enzymes play a central role in the upstream synthesis of precursors of trypanothione, a key molecule involved in Sb-resistance in Leishmania parasites, and suggest involvement of epigenetic regulation in response to drug exposure. These data re-enforce the importance of thiol metabolism in Leishmania Sb resistance, reveal previously unrecognized steps in the mechanism(s) of Sb tolerance, and suggest a cross-talk between drug resistance, metabolism and virulence.
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26
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Hansen C, Hansen EW, Hansen HR, Gammelgaard B, Stürup S. Reduction of Sb(V) in a human macrophage cell line measured by HPLC-ICP-MS. Biol Trace Elem Res 2011; 144:234-43. [PMID: 21618006 DOI: 10.1007/s12011-011-9079-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 05/10/2011] [Indexed: 11/28/2022]
Abstract
Drugs based on pentavalent antimony are first-line treatment of the parasite disease leishmaniasis. It is generally believed that Sb(V) acts as a prodrug, which is activated by reduction to Sb(III); however, the site of reduction is not known. It has been hypothesised that the reduction takes place in the parasites' host cells, the macrophages. In this study, the human macrophage cell line Mono Mac 6 was exposed to Sb(V) in form of the drug sodium stibogluconate (Pentostam™). Cell extracts were analysed for Sb species by high-performance liquid chromatography with inductively coupled plasma-mass spectrometry detection. We found that Sb(V) is actually reduced to Sb(III) in the macrophages; up to 23% of the intracellular Sb was found as Sb(III). Transfer of the cells to Sb-free medium rapidly decreased their Sb(V) and Sb(III) content. Induction of the cell's production of reactive oxygen species did not have any marked effect on the intracellular amounts of Sb(III).
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Affiliation(s)
- Claus Hansen
- Department of Pharmaceutics and Analytical Chemistry, University of Copenhagen, Universitetsparken 2, DK, 2100, Copenhagen Ø, Denmark.
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27
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Antimony resistance in leishmania, focusing on experimental research. J Trop Med 2011; 2011:695382. [PMID: 22174724 PMCID: PMC3235892 DOI: 10.1155/2011/695382] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 08/24/2011] [Accepted: 09/05/2011] [Indexed: 12/02/2022] Open
Abstract
Leishmaniases are parasitic diseases that spread in many countries with a prevalence of 12 million cases. There are few available treatments and antimonials are still of major importance in the therapeutic strategies used in most endemic regions. However, resistance toward these compounds has recently emerged in areas where the replacement of these drugs is mainly limited by the cost of alternative molecules. In this paper, we reviewed the studies carried out on antimonial resistance in Leishmania. Several common limitations of these works are presented before prevalent approaches to evidence antimonial resistance are related. Afterwards, phenotypic determination of resistance is described, then confronted to clinical outcome. Finally, we detail molecular mechanisms and targets involved in resistance and already identified in vitro within selected mutant strains or in clinical isolates.
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28
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Treiger Borborema SE, Schwendener RA, Osso Junior JA, de Andrade Junior HF, do Nascimento N. Uptake and antileishmanial activity of meglumine antimoniate-containing liposomes in Leishmania (Leishmania) major-infected macrophages. Int J Antimicrob Agents 2011; 38:341-7. [DOI: 10.1016/j.ijantimicag.2011.05.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 05/05/2011] [Accepted: 05/11/2011] [Indexed: 11/30/2022]
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Haldar AK, Sen P, Roy S. Use of antimony in the treatment of leishmaniasis: current status and future directions. Mol Biol Int 2011; 2011:571242. [PMID: 22091408 PMCID: PMC3196053 DOI: 10.4061/2011/571242] [Citation(s) in RCA: 215] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Accepted: 03/05/2011] [Indexed: 01/05/2023] Open
Abstract
In the recent past the standard treatment of kala-azar involved the use of pentavalent antimonials Sb(V). Because of progressive rise in treatment failure to Sb(V) was limited its use in the treatment program in the Indian subcontinent. Until now the mechanism of action of Sb(V) is not very clear. Recent studies indicated that both parasite and hosts contribute to the antimony efflux mechanism. Interestingly, antimonials show strong immunostimulatory abilities as evident from the upregulation of transplantation antigens and enhanced T cell stimulating ability of normal antigen presenting cells when treated with Sb(V) in vitro. Recently, it has been shown that some of the peroxovanadium compounds have Sb(V)-resistance modifying ability in experimental infection with Sb(V) resistant Leishmania donovani isolates in murine model. Thus, vanadium compounds may be used in combination with Sb(V) in the treatment of Sb(V) resistance cases of kala-azar.
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Affiliation(s)
- Arun Kumar Haldar
- Division of Infectious Diseases and Immunology, Indian Institute of Chemical Biology, Council of Scientific and Industrial Research, 4 Raja S. C. Mullick Road, Kolkata West Bengal 700032, India
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Metalloid transport by aquaglyceroporins: consequences in the treatment of human diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 679:57-69. [PMID: 20666224 DOI: 10.1007/978-1-4419-6315-4_5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Metalloids can severely harm human physiology in a toxicological sense if taken up from the environment in acute high doses or chronically. However, arsenic or antimony containing drugs are still being used as treatment and are often the sole regime for certain forms of cancer, mainly types of leukemia and diseases caused by parasites, such as sleeping sickness or leishmaniasis. In this chapter, we give an outline of the positive effects of arsenicals and antimonials against such diseases, we summarize data on uptake pathways through human and parasite aquaglyceroporins and we discuss the progress and options in the development of therapeutic aquaporin and aquaglyceroporin inhibitor compounds.
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Frézard F, Demicheli C, Ribeiro RR. Pentavalent antimonials: new perspectives for old drugs. Molecules 2009; 14:2317-36. [PMID: 19633606 PMCID: PMC6254722 DOI: 10.3390/molecules14072317] [Citation(s) in RCA: 277] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Revised: 06/15/2009] [Accepted: 06/22/2009] [Indexed: 12/26/2022] Open
Abstract
Pentavalent antimonials, including meglumine antimoniate and sodium stibogluconate, have been used for more than half a century in the therapy of the parasitic disease leishmaniasis. Even though antimonials are still the first-line drugs, they exhibit several limitations, including severe side effects, the need for daily parenteral administration and drug resistance. The molecular structure of antimonials, their metabolism and mechanism of action are still being investigated. Some recent studies suggest that pentavalent antimony acts as a prodrug that is converted to active and more toxic trivalent antimony. Other works support the direct involvement of pentavalent antimony. Recent data suggest that the biomolecules, thiols and ribonucleosides, may mediate the actions of these drugs. This review will summarize the progress to date on the chemistry and biochemistry of pentavalent antimony. It will also present the most recent works being done to improve antimonial chemotherapy. These works include the development of simple synthetic methods for pentavalent antimonials, liposome-based formulations for targeting the Leishmania parasites responsible for visceral leishmaniasis and cyclodextrin-based formulations to promote the oral delivery of antimony.
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Affiliation(s)
- Frédéric Frézard
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Pampulha, 31270-901 Belo Horizonte, MG, Brazil; E-mail: (R.R.)
- Author to whom correspondence should be addressed; E-Mail:
| | - Cynthia Demicheli
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Pampulha, 31270-901 Belo Horizonte, MG, Brazil; E-mail: (C.D.)
| | - Raul R. Ribeiro
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Pampulha, 31270-901 Belo Horizonte, MG, Brazil; E-mail: (R.R.)
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In vitro susceptibilities of Leishmania donovani promastigote and amastigote stages to antileishmanial reference drugs: practical relevance of stage-specific differences. Antimicrob Agents Chemother 2009; 53:3855-9. [PMID: 19546361 DOI: 10.1128/aac.00548-09] [Citation(s) in RCA: 185] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The in vitro susceptibilities of the reference strain Leishmania donovani MHOM/ET/67/L82 to sodium stibogluconate, amphotericin B, miltefosine, and the experimental compound PX-6518 were determined for extracellular log-phase promastigotes, established axenic amastigotes, fresh spleen-derived amastigotes, and intracellular amastigotes in primary mouse peritoneal macrophages. Susceptibility to amphotericin B did not differ across the various axenic models (50% inhibitory concentrations [IC50], 0.6 to 0.7 microM), and amphotericin B showed slightly higher potency against intracellular amastigotes (IC50, 0.1 to 0.4 microM). A similar trend was observed for miltefosine, with comparable efficacies against the extracellular (IC50, 0.4 to 3.8 microM) and intracellular (IC50, 0.9 to 4.3 microM) stages. Sodium stibogluconate, used either as Pentostam or as a crystalline substance, was inactive against all axenic stages (IC50, >64 microg SbV/ml) but showed good efficacy against intracellular amastigotes (IC50, 22 to 28 microg SbV/ml); the crystalline substance was about two to three times more potent (IC50, 9 to 11 microg SbV/ml). The activity profile of PX-6518 was comparable to that of sodium stibogluconate, but at a much higher potency (IC50, 0.1 microg/ml). In conclusion, the differential susceptibility determines which in vitro models are appropriate for either drug screening or resistance monitoring of clinical field isolates. Despite the more complex and labor-intensive protocol, the current results support the intracellular amastigote model as the gold standard for in vitro Leishmania drug discovery research and for evaluation of the resistance of field strains, since it also includes host cell-mediated effects. Axenic systems can be recommended only for compounds for which no cellular mechanisms are involved, for example, amphotericin B and miltefosine.
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Abstract
Aquaglyceroporin (AQP) channels facilitate the diffusion of a wide range of neutral solutes, including water, glycerol, and other small uncharged solutes. More recently, AQPs have been shown to allow the passage of trivalent arsenic and antimony compounds. Arsenic and antimony are metalloid elements. At physiological pH, the trivalent metalloids behave as molecular mimics of glycerol, and are conducted through AQP channels. Arsenicals and antimonials are extremely toxic to cells. Despite their toxicity, both metalloids are used as chemotherapeutic agents for the treatment of cancer and protozoan parasitic diseases. The metalloid homeostasis property of AQPs can be a mixed blessing. In some cases, AQPs form part of the detoxification pathway, and extrude metalloids from cells. In other instances, AQPs allow the transport of metalloids into cells, thereby conferring sensitivity. Understanding the factors that modulate AQP expression will aid in a better understanding of metalloid toxicity and also provide newer approaches to metalloid based chemotherapy.
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Antimony resistance and trypanothione in experimentally selected and clinical strains of Leishmania panamensis. Antimicrob Agents Chemother 2008; 52:4503-6. [PMID: 18824610 DOI: 10.1128/aac.01075-08] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The participation of trypanothione in clinical and experimental antimony (Sb) resistance in Leishmania panamensis was examined by using specific inhibitors. Buthionine sulfoximine (BSO) significantly reversed the resistance to trivalent Sb (Sb(III)) of promastigotes of experimentally derived Sb-resistant lines, supporting the participation of a trypanothione-mediated mechanism of resistance. In contrast, promastigotes of strains isolated at the time of clinical treatment failure and resistant to pentavalent Sb (Sb(V)) as intracellular amastigotes were not cross resistant to Sb(III), and BSO had little or no effect on susceptibility. Difluoromethylornithine did not alter the Sb(III) susceptibilities of experimentally selected lines or clinical strains. The mechanisms of acquired resistance emerging in clinical settings may differ from those selected by in vitro exposure to Sb.
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Abstract
Two new physalins, 16,24-cyclo-13,14-secoergosta-2-ene-18,26-dioic acid-14 : 17,14 : 27-diepoxy-11beta,13,20,22-tetrahydroxy-5alpha-methoxy-1,15-dioxo-gamma-lactone delta-lactone (1), and 16,24-cyclo-13,14-secoergosta-2-ene-18,26-dioic acid-14 : 17,14 : 27-diepoxy-5alpha,11beta,13,20,22-pentahydroxy-1,6,15-trioxo-gamma-lactone delta-lactone (2), have been isolated from the whole plant of Physalis minima Linn. (var. indica). Their structures were deduced on the basis of spectroscopic analysis. Both of these compounds have shown potent leishmanicidal activity against the promastigotes of Leishmania major.
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Affiliation(s)
- M Iqbal Choudhary
- H.E.J. Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi 75270, Pakistan.
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Papadopoulou B, Kündig C, Singh A, Ouellette M. Drug resistance in Leishmania: similarities and differences to other organisms. Drug Resist Updat 2007; 1:266-78. [PMID: 16904409 DOI: 10.1016/s1368-7646(98)80007-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/1998] [Revised: 06/19/1998] [Accepted: 06/19/1998] [Indexed: 11/28/2022]
Abstract
The main line of defense available against parasitic protozoa is chemotherapy. Drug resistance has emerged however, as a primary obstacle to the successful treatment and control of parasitic diseases. Leishmania spp., the causative agents of leishmaniasis, have served as a useful model for studying mechanisms of drug resistance in vitro. Antimonials and amphotericin B are the first line drugs to treat Leishmania followed by pentamidine and a number of other drugs. Parasites resistant against all these classes of drugs have been selected under laboratory conditions. A multiplicity of resistance mechanisms has been detected, the most prevalent being gene amplification and transport mutations. With the tools now available, it should be possible to elucidate the mechanisms that govern drug resistance in field isolates and develop more effective chemotherapeutic agents.
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Affiliation(s)
- B Papadopoulou
- Centre de Recherche en Infectiologie du Centre de Recherche du CHUL et Départment de Biologie Médicale, Division de Microbiologie, Faculté de Médecine, Université Laval, Québec, Canada GIV 4G2.
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dos Santos Ferreira C, de Castro Pimenta AM, Demicheli C, Frézard F. Characterization of reactions of antimoniate and meglumine antimoniate with a guanine ribonucleoside at different pH. Biometals 2007; 19:573-81. [PMID: 16937264 DOI: 10.1007/s10534-006-0001-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2005] [Accepted: 01/03/2006] [Indexed: 11/28/2022]
Abstract
It has been shown previously that Sb(V) forms mono- and bis-adducts with adenine and guanine ribonucleosides, suggesting that ribonucleosides may be a target for pentavalent antimonial drugs in the treatment of leishmaniasis. In the present work, the reactions of antimoniate (KSb(OH)(6)) and meglumine antimoniate (MA) with guanosine 5'-monophosphate (GMP) have been characterized at 37 degrees C in aqueous solution and two different pH (5 and 6.5), using ESI(-)-MS and (1)H NMR. Acid and base species for both 1:1 and 1:2 Sb(V)-GMP complexes were identified by ESI(-)-MS. The (1)H NMR anomeric region was explored for determining the concentrations of mono- and bis-adducts. This allows for the determination of stability constants for these complexes (5,900 L mol(-1) for 1:1 complex and 370 L mol(-1) for 1:2 complex, at pD 5 and 37 degrees C). Kinetic studies at different pH indicated that formation and dissociation of both 1:1 and 1:2 Sb-GMP complexes are slow processes and favored at acidic pH (2,150 L mol(-1) h(-1) for the rate constant of 1:1 complex formation and 0.25 h(-1) for the rate constant of 1:1 complex dissociation, at pD 5 and 37 degrees C). When MA was used, instead of antimoniate, formation of 1:1 Sb-GMP complex occurred, but with a slower rate constant. Assuming that MA consists essentially of a 1:1 Sb-meglumine complex, a stability constant for MA could also be estimated (8,600 L mol(-1) at pD 5 and 37 degrees C). Thermodynamic and kinetic data are consistent with the formation of 1:1 Sb-ribonucleoside complexes in vertebrate hosts, following treatment with pentavalent antimonial drugs.
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Affiliation(s)
- Cláudio dos Santos Ferreira
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Pampulha, 31270-901, Belo Horizonte, MG, Brazil
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Abstract
Leishmaniasis causes significant morbidity and mortality worldwide. The disease is endemic in developing countries of tropical regions, and in recent years economic globalization and increased travel have extended its reach to people in developed countries. In the absence of effective vaccines and vector-control measures, the main line of defence against the disease is chemotherapy. Organic pentavalent antimonials [Sb(V)] have been the first-line drugs for the treatment of leishmaniasis for the last six decades, and clinical resistance to these drugs has emerged as a primary obstacle to successful treatment and control. A multiplicity of resistance mechanisms have been described in resistantLeishmaniamutants developedin vitroby stepwise increases of the concentration of either antimony [Sb(III)] or the related metal arsenic [As(III)], the most prevalent mechanism being upregulated Sb(III) detoxification and sequestration. With the availability of resistant field isolates, it has now become possible to elucidate mechanisms of clinical resistance. The present review describes the mechanisms of antimony resistance inLeishmaniaand highlights the links between previous hypotheses and current developments in field studies. Unravelling the molecular mechanisms of clinical resistance could allow the prevention and circumvention of resistance, as well as rational drug design for the treatment of drug-resistantLeishmania.
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de Souza ROMA, Pereira VLP, Muzitano MF, Falcão CAB, Rossi-Bergmann B, Filho EBA, Vasconcellos MLAA. High selective leishmanicidal activity of 3-hydroxy-2-methylene-3-(4-bromophenyl)propanenitrile and analogous compounds. Eur J Med Chem 2006; 42:99-102. [PMID: 17010481 DOI: 10.1016/j.ejmech.2006.07.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2006] [Revised: 07/06/2006] [Accepted: 07/21/2006] [Indexed: 11/20/2022]
Abstract
Sixteen not new aromatic compounds were prepared by one-pot reaction i.e. through Baylis-Hillman reaction and were the first time evaluated against promastigote Leishmania amazonensis and infected mammalian cells. Most of the compounds were selectively more active against amastigotes than the reference drug sodium stibogluconate (Pentostam, IC(50)=44.7 microM). We found that 3-hydroxy-2-methylene-3-(4-bromophenyl) propanenitrile (13) was the most active (IC(50)=12.5 microM) and safer compound (0.0 (0.9); % macrophage LDH release), being the lead compound.
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Affiliation(s)
- R O M A de Souza
- Núcleo de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro, Bloco H, CCS, Ilha do Fundão, Rio de Janeiro, RJ 21941-590, Brazil
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40
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Dopp E, Hartmann LM, Florea AM, von Recklinghausen U, Rabieh S, Shokouhi B, Hirner AV, Rettenmeier AW. Trimethylantimony dichloride causes genotoxic effects in Chinese hamster ovary cells after forced uptake. Toxicol In Vitro 2006; 20:1060-5. [PMID: 16527445 DOI: 10.1016/j.tiv.2006.01.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2005] [Revised: 01/11/2006] [Accepted: 01/25/2006] [Indexed: 10/24/2022]
Abstract
In our study, we demonstrate that trimethylantimony dichloride (TMSb) does not induce micronucleus (MN) formation, chromosome aberrations (CA) or sister chromatid exchanges (SCE) under normal conditions in Chinese hamster ovary (CHO-9) cells in vitro up to an applied concentration of 1 mM, nor is it significantly cytotoxic. TMSb is taken up by the cells in a dose-dependent manner, but the percentage uptake of incubation substrate is low (max 0.05%). Intracellular TMSb concentration is two-fold increased after electroporation and under these forced uptake conditions MN formation is also significantly elevated. These data indicate that resistance to TMSb in CHO-9 cells occurs at the uptake and not at the intracellular level.
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Affiliation(s)
- E Dopp
- Institute of Hygiene and Occupational Medicine, University Hospital Essen, Hufelandstrasse 55, 45122 Essen, Germany.
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Mookerjee Basu J, Mookerjee A, Sen P, Bhaumik S, Sen P, Banerjee S, Naskar K, Choudhuri SK, Saha B, Raha S, Roy S. Sodium antimony gluconate induces generation of reactive oxygen species and nitric oxide via phosphoinositide 3-kinase and mitogen-activated protein kinase activation in Leishmania donovani-infected macrophages. Antimicrob Agents Chemother 2006; 50:1788-97. [PMID: 16641451 PMCID: PMC1472228 DOI: 10.1128/aac.50.5.1788-1797.2006] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Pentavalent antimony complexes, such as sodium stibogluconate and sodium antimony gluconate (SAG), are still the first choice for chemotherapy against various forms of leishmaniasis, including visceral leishmaniasis, or kala-azar. Although the requirement of a somewhat functional immune system for the antileishmanial action of antimony was reported previously, the cellular and molecular mechanism of action of SAG was not clear. Herein, we show that SAG induces extracellular signal-regulated kinase 1 (ERK-1) and ERK-2 phosphorylation through phosphoinositide 3-kinase (PI3K), protein kinase C, and Ras activation and p38 mitogen-activated protein kinase (MAPK) phosphorylation through PI3K and Akt activation. ERK-1 and ERK-2 activation results in an increase in the production of reactive oxygen species (ROS) 3 to 6 h after SAG treatment, while p38 MAPK activation and subsequent tumor necrosis factor alpha release result in the production of nitric oxide (NO) 24 h after SAG treatment. Thus, this study has provided the first evidence that SAG treatment induces activation of some important components of the intracellular signaling pathway, which results in an early wave of ROS-dependent parasite killing and a stronger late wave of NO-dependent parasite killing. This opens up the possibility of this metalloid chelate being used in the treatment of various diseases either alone or in combination with other drugs and vaccines.
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Affiliation(s)
- Jayati Mookerjee Basu
- Department of Immunology, Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, India.
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Mehta A, Shaha C. Mechanism of metalloid-induced death in Leishmania spp.: role of iron, reactive oxygen species, Ca2+, and glutathione. Free Radic Biol Med 2006; 40:1857-68. [PMID: 16678023 DOI: 10.1016/j.freeradbiomed.2006.01.024] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Accepted: 01/20/2006] [Indexed: 01/24/2023]
Abstract
There is growing evidence that metalloid-induced cell death in protozoan parasites is due to oxidative injury; however, the biochemical changes related to this event are not fully understood. Leishmania spp. demonstrated cross-resistance to two related metalloids, arsenic and antimony, and both metalloids induced cell death accompanied by cell shrinkage and DNA fragmentation that was preceded by an increase in reactive oxygen species. Both drugs caused mitochondrial dysfunction in terms of loss of membrane potential and a drop in ATP levels. Arsenic treatment resulted in an elevation of intracellular Ca2+ levels that did not occur with antimony exposure. Cellular glutathione level was reduced after antimony treatment but arsenic did not affect glutathione. Inhibition of Ca2+ influx during arsenic treatment reduced cell death, whereas supplementation of glutathione during antimony treatment rescued cell loss. Under iron-depleted conditions, the cytotoxic effects of arsenic and antimony did not occur and cell survival increased; in contrast, the presence of excess iron resulted in higher cell death. Therefore, this study provides a new possibility that iron can potentiate parasite death induced by metalloids like arsenic and antimony. In addition, an important observation is that the two similar metalloids produce toxicity by very different mechanisms.
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Affiliation(s)
- Ashish Mehta
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
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Dzamitika SA, Falcão CAB, de Oliveira FB, Marbeuf C, Garnier-Suillerot A, Demicheli C, Rossi-Bergmann B, Frézard F. Role of residual Sb(III) in meglumine antimoniate cytotoxicity and MRP1-mediated resistance. Chem Biol Interact 2006; 160:217-24. [PMID: 16524568 DOI: 10.1016/j.cbi.2006.01.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 01/25/2006] [Accepted: 01/26/2006] [Indexed: 11/19/2022]
Abstract
Despite the clinical use of pentavalent antimonials for more than half a century, their metabolism in mammals and mechanisms of action and toxicity remain poorly understood. It has been proposed that the more active and toxic trivalent antimony form Sb(III) plays a critical role in their antileishmanial activity and toxicity. The aim of this work was to investigate the role of residual Sb(III) both in the antileishmanial/antitumoral activities of the pentavalent meglumine antimoniate and in the MRP1 (multidrug resistance-associated protein 1)-mediated resistance to this drug. Samples of meglumine antimoniate differing in their amount of residual Sb(III) (meglumine antimoniate synthesized either from SbCl(5) or from KSb(OH)(6) as well as commercially-available meglumine antimoniate) were evaluated in vitro and in vivo on Leishmania amazonensis infections, as well as for their cytotoxicity to normal and MRP1-overexpressing GLC4 cell lines. Although in vitro the two most effective drugs contained the highest levels of Sb(III), no correlation was found in vivo between the antileishmanial activity of meglumine antimoniate and its residual Sb(III) content, suggesting that residual Sb(III) contributes only marginally to the drug antileishmanial activity. On the other hand, the GLC4 cells growth inhibition data strongly suggests a marked contribution of residual Sb(III). Additionally, the potassium salt of antimoniate (non-complexed form of Sb(V)) was found to be more cytotoxic than meglumine antimoniate. Although MRP1-overexpressing GLC4 cells showed a marked resistance to trivalent antimonials, cross-resistance to meglumine antimoniate was observed only for the products that contained relatively high levels of Sb(III) (at least 0.03% by weight), suggesting that MRP1 mediates resistance to Sb(III) but not to Sb(V). In conclusion, our data strongly suggest that residual Sb(III) in pentavalent antimonial drugs does not contribute significantly to their antileishmanial activity, but is responsible for their cytotoxic activity against mammalian cells and the MRP1-mediated resistance to these drugs.
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Affiliation(s)
- Simplice A Dzamitika
- Laboratoire BioMoCeTi, UMR 7033, Université Paris Nord, 74 Rue Marcel Cachin, 93017 Bobigny, France
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Decuypere S, Rijal S, Yardley V, De Doncker S, Laurent T, Khanal B, Chappuis F, Dujardin JC. Gene expression analysis of the mechanism of natural Sb(V) resistance in Leishmania donovani isolates from Nepal. Antimicrob Agents Chemother 2006; 49:4616-21. [PMID: 16251303 PMCID: PMC1280167 DOI: 10.1128/aac.49.11.4616-4621.2005] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Control of visceral leishmaniasis (VL) is being challenged by the emergence of natural resistance against the first line of treatment, pentavalent antimonials [Sb(V)]. An insight into the mechanism of natural Sb(V) resistance is required for the development of efficient strategies to monitor the emergence and spreading of Sb(V) resistance in countries where VL is endemic. In this work, we have focused on the mechanism of natural Sb(V) resistance emerging in Nepal, a site where anthroponotic VL is endemic. Based on the current knowledge of Sb(V) metabolism and of the in vitro trivalent antimonial [Sb(III)] models of resistance to Leishmania spp., we selected nine genes for a comparative transcriptomic study on natural Sb(V)-resistant and -sensitive Leishmania donovani isolates. Differential gene expression patterns were observed for the genes coding for 2-thiol biosynthetic enzymes, gamma-glutamylcysteine synthetase (GCS) and ornithine decarboxylase (ODC), and for the Sb(III) transport protein aquaglyceroporin 1 (AQP1). The results indicate that the mechanism for natural Sb(V) resistance partially differs from the mechanism reported for in vitro Sb(III) resistance. More specifically, we hypothesize that natural Sb(V) resistance results from (i) a changed thiol metabolism, possibly resulting in inhibition of Sb(V) activation in amastigotes, and (ii) decreased uptake of the active drug Sb(III) by amastigotes.
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Affiliation(s)
- Saskia Decuypere
- Unit of Molecular Parasitology, Department of Parasitology, Prince Leopold Institute of Tropical Medicine, Antwerp, Belgium
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Kuryshev YA, Wang L, Wible BA, Wan X, Ficker E. Antimony-based antileishmanial compounds prolong the cardiac action potential by an increase in cardiac calcium currents. Mol Pharmacol 2006; 69:1216-25. [PMID: 16418337 DOI: 10.1124/mol.105.019281] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Antimonial agents are a mainstay for the treatment of leishmaniasis, a group of protozoal diseases that includes visceral leishmaniasis, or Kala Azar. Chemotherapy with trivalent potassium antimony tartrate (PAT) and, more importantly, pentavalent antimony-carbohydrate complexes, such as sodium stibogluconate (SSG), has been reported to prolong the QT interval and produce life-threatening arrhythmias. PAT is chemically related to As2O3, which alters cardiac excitability by inhibition of human ether a-go-go related gene (hERG) trafficking and an increase of cardiac calcium currents. In this study, we report that PAT does not block hERG currents on short-term exposure but reduces current density on long-term exposure (IC50, 11.8 microM) and inhibits hERG maturation on Western blots (IC50, 62 microM). Therapeutic concentrations of 0.3 microM PAT increase cardiac calcium currents from -4.8 +/- 0.7 to -7.3 +/- 0.5 pA/pF at 10 mV. In marked contrast, pentavalent SSG, the drug of choice for the treatment of leishmaniasis, did not affect hERG/IKr or any other cardiac potassium current at therapeutic concentrations. However, both cardiac sodium and calcium currents were significantly increased on long-term exposure to 30 microM SSG in isolated guinea pig ventricular myocytes. We propose that the increase in calcium currents from -3.2 +/- 0.3 to -5.1 +/- 0.3 pA/pF at 10 mV prolongs APD90 from 464 +/- 35 to 892 +/- 64 ms. Our data suggest that conversion of Sb(V) into active Sb(III) in patients produces a common mode of action for antimonial drugs, which define a novel compound class that increases cardiac risk not by a reduction of hERG/IKr currents but-for the first time-by an increase in cardiac calcium currents.
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Affiliation(s)
- Yuri A Kuryshev
- Rammelkamp Center, MetroHealth Medical Center, 2500 MetroHealth Drive, Cleveland, OH 44109, USA
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Ashutosh, Gupta S, Ramesh, Sundar S, Goyal N. Use of Leishmania donovani field isolates expressing the luciferase reporter gene in in vitro drug screening. Antimicrob Agents Chemother 2005; 49:3776-83. [PMID: 16131481 PMCID: PMC1195392 DOI: 10.1128/aac.49.9.3776-3783.2005] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2005] [Revised: 03/03/2005] [Accepted: 05/28/2005] [Indexed: 11/20/2022] Open
Abstract
Currently available primary screens for the selection of candidate antileishmanial compounds are not ideal. These techniques are time-consuming, laborious, and difficult to scale and require macrophages, which limit their use for high-throughput screening. We have developed Leishmania donovani field isolates that constitutively express the firefly luciferase reporter gene (luc) as a part of an episomal vector. An excellent correlation between parasite number and luciferase activity was observed. luc expression was stable, even in the absence of drug selection, for 4 weeks. The transfectants were infective to macrophages, and intracellular amastigotes exhibited luciferase activity. The suitability of these recombinant field isolates for in vitro screening of antileishmanial drugs was established. The luciferase-expressing sodium stibogluconate-resistant cell lines offer a model for the screening of compounds for resistance. The system is in routine use at the Central Drug Research Institute, Lucknow, India, for high-throughput screening of newly synthesized compounds.
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Affiliation(s)
- Ashutosh
- Division of Biochemistry, Central Drug Research Institute, Chatter Manzil Palace, M. G. Road, Lucknow 226 001 (UP), India
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47
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Hadjikakou SK, Antoniadis CD, Hadjiliadis N, Kubicki M, Binolis J, Karkabounas S, Charalabopoulos K. Synthesis and characterization of new water stable antimony(III) complex with pyrimidine-2-thione and in vitro biological study. Inorganica Chim Acta 2005. [DOI: 10.1016/j.ica.2004.06.028] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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48
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Schubach ADO, Marzochi KBF, Moreira JS, Schubach TMP, Araújo ML, Vale ACFD, Passos SRL, Marzochi MCDA. Retrospective study of 151 patients with cutaneous leishmaniasis treated with meglumine antimoniate. Rev Soc Bras Med Trop 2005; 38:213-7. [PMID: 15895170 DOI: 10.1590/s0037-86822005000300001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We retrospectively analyzed a series of 151 cases of cutaneous leishmaniasis treated between 1967 and 1982. One-hundred-and-thirty-nine (92%) patients presented with active lesions and were treated with daily doses of meglumine antimoniate: 81 adults received a 5-ml vial IM and 58 children received 1 to 5ml. Forty-five (32.4%) patients underwent continuous treatment with meglumine antimoniate for 25 to 116 days without rest intervals, and 94 (67.6%) intermittent treatment with 2 to 5 series of meglumine antimoniate. Intermittent series could include schedules of daily IM applications for 10 to 25 days each and intervals varying from 10 to 60 days. Antimony dose was calculated for 66 (47.5%) patients and ranged from 3.9 to 28.7 Sb5+/kg/day. Of these, 35 patients received >10mg and 31 patients <10mg Sb5+/kg/day. Median time of healing was longer for lesions on the legs and feet - 67.5 days versus 48.7 days (p < 0.001) for other sites. However, there were no significant differences in the median time of healing between adults and children, intermittent and continuous regimens or high and low antimony doses. Fifty-one patients were reassessed 5 to 14 years after treatment and showed no evidence of disease. These results support further investigation (clinical trials) on treatment using low doses of antimony.
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Affiliation(s)
- Armando de Oliveira Schubach
- Centro de Referências em Leishmanioses, Instituto de Pesquisa Clínica Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
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49
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Alvarez M, Malécot CO, Gannier F, Lignon JM. Antimony-induced cardiomyopathy in guinea-pig and protection by L-carnitine. Br J Pharmacol 2005; 144:17-27. [PMID: 15644865 PMCID: PMC1575978 DOI: 10.1038/sj.bjp.0706030] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Revised: 09/16/2004] [Accepted: 09/20/2004] [Indexed: 11/09/2022] Open
Abstract
Antimony (Sb) is the mainstay for the treatment of Leishmaniasis. It has serious, often lethal, cardiovascular side effects. The objective of this study was to examine the effects of Sb treatment upon the electrocardiogram (ECG), myocyte contractility (assessed by monitoring sarcomere length during field stimulation), whole-cell action potential (AP) and calcium current (I(Ca)) of the guinea-pig and to evaluate L-carnitine as a cardioprotective agent. Guinea-pigs received daily injections of either saline, Sb(V), Sb(III), L-carnitine or L-carnitine with Sb(III). Eight lead ECGs were recorded under halothane anaesthesia every 4 days. At the end of each treatment regime, animals were killed and ventricular myocytes were enzymatically isolated. Treatment with Sb(V) for 26 days prolonged the QT interval of the ECG. Treatment with Sb(III) was lethal within 2 days for approximately 50% of the animals. The survivors showed ECG alterations similar to those described in man: T wave flattening and/or inversion, depression of the ST segment, and elongation of RR and QT intervals. Their ventricular myocytes showed impaired contraction responses to changes in stimulus frequency, elongated AP and reduced I(Ca). Combined treatment with L-carnitine and Sb(III) delayed mortality. Prior treatment with L-carnitine followed by combined treatment with L-carnitine and Sb(III) reduced mortality to <10% over 12 days and these animals showed normal ECG. Their myocytes showed normal contractility and AP. It is concluded that L-carnitine has a preventive cardioprotective role against antimony-induced cardiomyopathy. The mechanism of action of L-carnitine may be to counter oxidative stress caused by Sb(III).
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Affiliation(s)
- Marco Alvarez
- CNRS UMR 6542, Physiologie des Cellules Cardiaques et Vasculaires, Faculté des Sciences, Parc de Grandmont, 37200 Tours, France
| | - Claire O Malécot
- CNRS UMR 6542, Physiologie des Cellules Cardiaques et Vasculaires, Faculté des Sciences, Parc de Grandmont, 37200 Tours, France
| | - François Gannier
- CNRS UMR 6542, Physiologie des Cellules Cardiaques et Vasculaires, Faculté des Sciences, Parc de Grandmont, 37200 Tours, France
| | - Jacques M Lignon
- CNRS UMR 6542, Physiologie des Cellules Cardiaques et Vasculaires, Faculté des Sciences, Parc de Grandmont, 37200 Tours, France
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Walker J, Saravia NG. INHIBITION OF LEISHMANIA DONOVANI PROMASTIGOTE DNA TOPOISOMERASE I AND HUMAN MONOCYTE DNA TOPOISOMERASES I AND II BY ANTIMONIAL DRUGS AND CLASSICAL ANTITOPOISOMERASE AGENTS. J Parasitol 2004; 90:1155-62. [PMID: 15562618 DOI: 10.1645/ge-3347] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
We have compared the inhibitor sensitivities of DNA topoisomerase I (TOPI) from Leishmania donovani promastigotes and TOPs I and II of human monocytes using pentavalent and trivalent antimonials (SbV, SbIII) and classical TOP inhibitors. Bis-benzimidazoles (Hoechst-33258 and -33342) were potent inhibitors of both parasite and human TOPI, but Hoechst-33342 was markedly less cytotoxic to promastigotes than to monocytes in vitro. Leishmania donovani was also considerably less sensitive than monocytes to camptothecin, both at enzyme and cellular levels. Sodium stibogluconate (SSG) was the only antimonial to inhibit TOPI, exhibiting a significant (P < 0.05) 3-fold greater potency against the L. donovani enzyme but showed low cytotoxicities against intact promastigotes. The SbV meglumine antimoniate failed to inhibit TOPI and showed negligible cytotoxicities, whereas SbIII drugs were lethal to parasites and monocytes yet poor inhibitors of TOPI. Monocyte TOPII was inhibited by bis-benzimidazoles and insensitive to antimonials and camptothecin. The disparity between the high leishmanicidal activity and low anti-TOPI potency of SbIII indicates that in vivo targeting of L. donovani TOPI by the reductive pathway of antimonial activation is improbable. Nevertheless, the potent direct inhibition of TOPI by SSG and the differential interactions of camptothecin with L. donovani and human TOPI support the possibility of developing parasite-specific derivatives.
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Affiliation(s)
- John Walker
- Centro Internacional de Entrenamiento e Investigaciones Medicas Avenida 1 Norte No. 3-03, AA 5390, Cali, Colombia.
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