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Sheikh SY, Hassan F, Shukla D, Bala S, Faruqui T, Akhter Y, Khan AR, Nasibullah M. A review on potential therapeutic targets for the treatment of leishmaniasis. Parasitol Int 2024; 100:102863. [PMID: 38272301 DOI: 10.1016/j.parint.2024.102863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 12/22/2023] [Accepted: 01/21/2024] [Indexed: 01/27/2024]
Abstract
Leishmania, a protozoan parasite, is responsible for the occurrence of leishmaniasis, a disease that is prevalent in tropical regions. Visceral Leishmaniasis (VL), also known as kala-azar in Asian countries, is one of the most significant forms of VL, along with Cutaneous Leishmaniasis (CL) and Mucocutaneous Leishmaniasis (ML). Management of this condition typically entails the use of chemotherapy as the sole therapeutic option. The current treatments for leishmaniasis present several drawbacks, including a multitude of side effects, prolonged treatment duration, disparate efficacy across different regions, and the emergence of resistance. To address this urgent need, it is imperative to identify alternative treatments that are both safer and more effective. The identification of appropriate pharmacological targets in conjunction with biological pathways constitutes the initial stage of drug discovery. In this review, we have addressed the key metabolic pathways that represent potential pharmacological targets as well as prominent treatment options for leishmaniasis.
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Affiliation(s)
- Sabahat Yasmeen Sheikh
- Department of Chemistry, Integral University, Dasauli, Kursi road, Lucknow 226026, India
| | - Firoj Hassan
- Department of Chemistry, Integral University, Dasauli, Kursi road, Lucknow 226026, India
| | - Deepanjali Shukla
- Department of Chemistry, Integral University, Dasauli, Kursi road, Lucknow 226026, India
| | - Shashi Bala
- Department of Chemistry, Lucknow University, Lucknow 226026, India
| | - Tabrez Faruqui
- Department of Biosciences, Integral University, Lucknow 226026, India
| | - Yusuf Akhter
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Vidya Vihar, Raebareli Road, Lucknow 226025, India
| | - Abdul Rahman Khan
- Department of Chemistry, Integral University, Dasauli, Kursi road, Lucknow 226026, India
| | - Malik Nasibullah
- Department of Chemistry, Integral University, Dasauli, Kursi road, Lucknow 226026, India.
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Pérez-Pertejo Y, García-Estrada C, Martínez-Valladares M, Murugesan S, Reguera RM, Balaña-Fouce R. Polyamine Metabolism for Drug Intervention in Trypanosomatids. Pathogens 2024; 13:79. [PMID: 38251386 PMCID: PMC10820115 DOI: 10.3390/pathogens13010079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/11/2024] [Accepted: 01/12/2024] [Indexed: 01/23/2024] Open
Abstract
Neglected tropical diseases transmitted by trypanosomatids include three major human scourges that globally affect the world's poorest people: African trypanosomiasis or sleeping sickness, American trypanosomiasis or Chagas disease and different types of leishmaniasis. Different metabolic pathways have been targeted to find antitrypanosomatid drugs, including polyamine metabolism. Since their discovery, the naturally occurring polyamines, putrescine, spermidine and spermine, have been considered important metabolites involved in cell growth. With a complex metabolism involving biosynthesis, catabolism and interconversion, the synthesis of putrescine and spermidine was targeted by thousands of compounds in an effort to produce cell growth blockade in tumor and infectious processes with limited success. However, the discovery of eflornithine (DFMO) as a curative drug against sleeping sickness encouraged researchers to develop new molecules against these diseases. Polyamine synthesis inhibitors have also provided insight into the peculiarities of this pathway between the host and the parasite, and also among different trypanosomatid species, thus allowing the search for new specific chemical entities aimed to treat these diseases and leading to the investigation of target-based scaffolds. The main molecular targets include the enzymes involved in polyamine biosynthesis (ornithine decarboxylase, S-adenosylmethionine decarboxylase and spermidine synthase), enzymes participating in their uptake from the environment, and the enzymes involved in the redox balance of the parasite. In this review, we summarize the research behind polyamine-based treatments, the current trends, and the main challenges in this field.
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Affiliation(s)
- Yolanda Pérez-Pertejo
- Departamento de Ciencias Biomédicas, Campus de Vegazana s/n, Universidad de León, 24071 León, Spain; (Y.P.-P.); (C.G.-E.); (R.M.R.)
- Instituto de Biomedicina (IBIOMED), Campus de Vegazana s/n, Universidad de León, 24071 León, Spain
| | - Carlos García-Estrada
- Departamento de Ciencias Biomédicas, Campus de Vegazana s/n, Universidad de León, 24071 León, Spain; (Y.P.-P.); (C.G.-E.); (R.M.R.)
- Instituto de Biomedicina (IBIOMED), Campus de Vegazana s/n, Universidad de León, 24071 León, Spain
| | | | - Sankaranarayanan Murugesan
- Medicinal Chemistry Research Laboratory, Department of Pharmacy, Birla Institute of Technology and Science-Pilani, Pilani 333031, India;
| | - Rosa M. Reguera
- Departamento de Ciencias Biomédicas, Campus de Vegazana s/n, Universidad de León, 24071 León, Spain; (Y.P.-P.); (C.G.-E.); (R.M.R.)
- Instituto de Biomedicina (IBIOMED), Campus de Vegazana s/n, Universidad de León, 24071 León, Spain
| | - Rafael Balaña-Fouce
- Departamento de Ciencias Biomédicas, Campus de Vegazana s/n, Universidad de León, 24071 León, Spain; (Y.P.-P.); (C.G.-E.); (R.M.R.)
- Instituto de Biomedicina (IBIOMED), Campus de Vegazana s/n, Universidad de León, 24071 León, Spain
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Travi BL, Cordeiro-da-Silva A, Dantas-Torres F, Miró G. Canine visceral leishmaniasis: Diagnosis and management of the reservoir living among us. PLoS Negl Trop Dis 2018; 12:e0006082. [PMID: 29324838 PMCID: PMC5764232 DOI: 10.1371/journal.pntd.0006082] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
This article reviews essential topics of canine visceral leishmaniasis (CVL) due to Leishmania infantum infection. It focuses on the current serological and molecular diagnostic methods used in epidemiological research and veterinary clinics to diagnose CVL and includes new point-of-care (POC) tests under development. The efficacy of different treatment regimens on the clinical improvement and infectiousness of dogs is also addressed. In the last section, the review provides a critical appraisal of the effectiveness of different control measures that have been implemented to curb disease transmission. Dogs are the principal reservoir hosts of L. infantum and consequently play a critical role in the transmission cycle of urban VL, which also affects humans. This review provides updated information on important topics such as diagnostic tests and dog treatments that improve dog health and decrease their transmission efficacy to insect vectors. A critical review of control measures is also provided.
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Affiliation(s)
- Bruno L. Travi
- Department of Internal Medicine-Division of Infectious Diseases, University of Texas Medical Branch, Galveston, Texas, United States of America
- * E-mail:
| | - Anabela Cordeiro-da-Silva
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Parasite Disease Group, Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Departamento de Ciências Biológicas, Faculdade de Farmácia da Universidade do Porto, Porto, Portugal
| | - Filipe Dantas-Torres
- Department of Immunology, Aggeu Magalhães Institute, Oswaldo Cruz Foundation, Recife, Pernambuco, Brazil
| | - Guadalupe Miró
- Veterinary Faculty, Animal Health Department, Universidad Complutense de Madrid, Madrid, Spain
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Mechanism of Action of Miltefosine on Leishmania donovani Involves the Impairment of Acidocalcisome Function and the Activation of the Sphingosine-Dependent Plasma Membrane Ca 2+ Channel. Antimicrob Agents Chemother 2017; 62:AAC.01614-17. [PMID: 29061745 DOI: 10.1128/aac.01614-17] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 10/12/2017] [Indexed: 11/20/2022] Open
Abstract
Leishmania donovani is the causing agent of visceral leishmaniasis, a common infection that affects millions of people from the most underdeveloped countries. Miltefosine is the only oral drug to treat infections caused by L. donovani Nevertheless, its mechanism of action is not well understood. While miltefosine inhibits the synthesis of phosphatidylcholine and also affects the parasite mitochondrion, inhibiting the cytochrome c oxidase, it is to be expected that this potent drug also produces its effect through other targets. In this context, it has been reported that the disruption of the intracellular Ca2+ homeostasis represents an important object for the action of drugs in trypanosomatids. Recently, we have described a plasma membrane Ca2+ channel in Leishmania mexicana, which is similar to the L-type voltage-gated Ca2+ channel (VGCC) present in humans. Remarkably, the parasite Ca2+ channel is activated by sphingosine, while the L-type VGCC is not affected by this sphingolipid. In the present work we demonstrated that, similarly to sphingosine, miltefosine is able to activate the plasma membrane Ca2+ channel from L. donovani Interestingly, nifedipine, the classical antagonist of the human channel, was not able to fully block the parasite plasma membrane Ca2+ channel, indicating that the mechanism of interaction is not identical to that of sphingosine. In this work we also show that miltefosine is able to strongly affect the acidocalcisomes from L. donovani, inducing the rapid alkalinization of these important organelles. In conclusion, we demonstrate two new mechanisms of action of miltefosine in L. donovani, both related to disruption of parasite Ca2+ homeostasis.
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Azzouz S, Lawton P. In vitro effects of purine and pyrimidine analogues on Leishmania donovani and Leishmania infantum promastigotes and intracellular amastigotes. Acta Parasitol 2017; 62:582-588. [PMID: 28682767 DOI: 10.1515/ap-2017-0070] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/26/2017] [Indexed: 01/19/2023]
Abstract
Inhibition of parasite metabolic pathways is a rationale for new chemotherapeutic strategies. The pyrimidine and purine salvage pathways are thus targets against Leishmania donovani and L. infantum, causative agents of visceral human leishmaniasis and canine leishmaniosis. The antiproliferative effect of the pyrimidine analogues Cytarabine and 5-fluorouracil and of the purine analogues Azathioprine and 6-mercaptopurine was evaluated in vitro on the promastigote and the intracellular amastigote stages of the parasite. Cytarabine and 5-fluorouracil were the best inhibitors against promastigotes, whereas 5- fluorouracil and azathioprine displayed the best efficacy against the amastigote stage. The ultrastructural study showed an important cytoplasmic vacuolization and with azathioprine and 5-fluorouracyl, a mitochondrial swelling and appearance of autophagosome-like structures. Alterations of the kinetoplast were also observed with 5-fluorouracil, all these damages eventually resulting in an autolysis process that triggered the subsequent death of the intracellular parasites.
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Uzcanga G, Lara E, Gutiérrez F, Beaty D, Beske T, Teran R, Navarro JC, Pasero P, Benítez W, Poveda A. Nuclear DNA replication and repair in parasites of the genus Leishmania: Exploiting differences to develop innovative therapeutic approaches. Crit Rev Microbiol 2016; 43:156-177. [PMID: 27960617 DOI: 10.1080/1040841x.2016.1188758] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Leishmaniasis is a common tropical disease that affects mainly poor people in underdeveloped and developing countries. This largely neglected infection is caused by Leishmania spp, a parasite from the Trypanosomatidae family. This parasitic disease has different clinical manifestations, ranging from localized cutaneous to more harmful visceral forms. The main limitations of the current treatments are their high cost, toxicity, lack of specificity, and long duration. Efforts to improve treatments are necessary to deal with this infectious disease. Many approved drugs to combat diseases as diverse as cancer, bacterial, or viral infections take advantage of specific features of the causing agent or of the disease. Recent evidence indicates that the specific characteristics of the Trypanosomatidae replication and repair machineries could be used as possible targets for the development of new treatments. Here, we review in detail the molecular mechanisms of DNA replication and repair regulation in trypanosomatids of the genus Leishmania and the drugs that could be useful against this disease.
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Affiliation(s)
- Graciela Uzcanga
- a Centro Internacional de Zoonosis, Facultad de Ciencias Químicas, Facultad de Medicina Veterinaria , Universidad Central del Ecuador , Quito , Ecuador.,b Programa Prometeo , SENESCYT, Whymper E7-37 y Alpallana, Quito , Ecuador.,c Facultad de Ciencias Naturales y Ambientales, Universidad Internacional SEK Calle Alberto Einstein sn y 5ta transversal , Quito , Ecuador.,d Fundación Instituto de Estudios Avanzados-IDEA , Caracas , Venezuela
| | - Eliana Lara
- a Centro Internacional de Zoonosis, Facultad de Ciencias Químicas, Facultad de Medicina Veterinaria , Universidad Central del Ecuador , Quito , Ecuador.,e Institute of Human Genetics , CNRS UPR 1142, 141 rue de la Cardonille, Equipe Labellisée Ligue Contre le Cancer , Montpellier cedex 5 , France
| | - Fernanda Gutiérrez
- a Centro Internacional de Zoonosis, Facultad de Ciencias Químicas, Facultad de Medicina Veterinaria , Universidad Central del Ecuador , Quito , Ecuador
| | - Doyle Beaty
- a Centro Internacional de Zoonosis, Facultad de Ciencias Químicas, Facultad de Medicina Veterinaria , Universidad Central del Ecuador , Quito , Ecuador
| | - Timo Beske
- a Centro Internacional de Zoonosis, Facultad de Ciencias Químicas, Facultad de Medicina Veterinaria , Universidad Central del Ecuador , Quito , Ecuador
| | - Rommy Teran
- a Centro Internacional de Zoonosis, Facultad de Ciencias Químicas, Facultad de Medicina Veterinaria , Universidad Central del Ecuador , Quito , Ecuador
| | - Juan-Carlos Navarro
- a Centro Internacional de Zoonosis, Facultad de Ciencias Químicas, Facultad de Medicina Veterinaria , Universidad Central del Ecuador , Quito , Ecuador.,f Universidad Central de Venezuela, Instituto de Zoología y Ecología Tropical , Caracas , Venezuela.,g Facultad de Ciencias Naturales y Ambientales, Universidad Internacional SEK, Calle Alberto Einstein sn y 5ta transversal , Quito , Ecuador
| | - Philippe Pasero
- e Institute of Human Genetics , CNRS UPR 1142, 141 rue de la Cardonille, Equipe Labellisée Ligue Contre le Cancer , Montpellier cedex 5 , France
| | - Washington Benítez
- a Centro Internacional de Zoonosis, Facultad de Ciencias Químicas, Facultad de Medicina Veterinaria , Universidad Central del Ecuador , Quito , Ecuador
| | - Ana Poveda
- a Centro Internacional de Zoonosis, Facultad de Ciencias Químicas, Facultad de Medicina Veterinaria , Universidad Central del Ecuador , Quito , Ecuador
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An update on the diagnosis and treatment of canine leishmaniosis caused by Leishmania infantum (syn. L. chagasi). Vet J 2014; 202:425-35. [PMID: 25266647 DOI: 10.1016/j.tvjl.2014.09.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 09/01/2014] [Accepted: 09/03/2014] [Indexed: 11/22/2022]
Abstract
Canine leishmaniosis caused by Leishmania infantum is still a common disease in endemic areas, such as the Mediterranean countries, and has progressively expanded into non-endemic areas like Central and Northern Europe. The aim of this article is to critically review current knowledge on the diagnosis and treatment of this disease. In dogs with typical clinical signs and clinicopathological abnormalities, diagnosis is relatively easy based on the exclusion of major differentials, the demonstration of the parasite (e.g., with lymph node and/or skin cytology) and the presence of Leishmania-specific immunoglobulin G antibodies (quantitative serology). In less typical cases, these criteria together with the exclusion of possible differentials and the demonstration of compatible histological lesions in affected organs and tissues form the basis for a sound diagnosis. In clinically healthy dogs, molecular techniques are the most sensitive means for detecting L. infantum infection. Treatment of canine leishmaniosis should follow clinical staging and is usually based on meglumine antimonate or miltefosine administration for a few weeks in combination with allopurinol for several months. However, allopurinol monotherapy may be used in very mild cases as well as in dogs with end stage kidney disease. Aminosidine administered once daily at a revised dosage shows some promise but additional controlled studies are needed. Close attention to published guidelines regarding treatment and follow-up is necessary to achieve the best possible therapeutic outcome.
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Roatt BM, Aguiar-Soares RDDO, Coura-Vital W, Ker HG, Moreira NDD, Vitoriano-Souza J, Giunchetti RC, Carneiro CM, Reis AB. Immunotherapy and Immunochemotherapy in Visceral Leishmaniasis: Promising Treatments for this Neglected Disease. Front Immunol 2014; 5:272. [PMID: 24982655 PMCID: PMC4055865 DOI: 10.3389/fimmu.2014.00272] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 05/27/2014] [Indexed: 11/25/2022] Open
Abstract
Leishmaniasis has several clinical forms: self-healing or chronic cutaneous leishmaniasis or post-kala-azar dermal leishmaniasis; mucosal leishmaniasis; visceral leishmaniasis (VL), which is fatal if left untreated. The epidemiology and clinical features of VL vary greatly due to the interaction of multiple factors including parasite strains, vectors, host genetics, and the environment. Human immunodeficiency virus infection augments the severity of VL increasing the risk of developing active disease by 100–2320 times. An effective vaccine for humans is not yet available. Resistance to chemotherapy is a growing problem in many regions, and the costs associated with drug identification and development, make commercial production for leishmaniasis, unattractive. The toxicity of currently drugs, their long treatment course, and limited efficacy are significant concerns. For cutaneous disease, many studies have shown promising results with immunotherapy/immunochemotherapy, aimed to modulate and activate the immune response to obtain a therapeutic cure. Nowadays, the focus of many groups centers on treating canine VL by using vaccines and immunomodulators with or without chemotherapy. In human disease, the use of cytokines like interferon-γ associated with pentavalent antimonials demonstrated promising results in patients that did not respond to conventional treatment. In mice, immunomodulation based on monoclonal antibodies to remove endogenous immunosuppressive cytokines (interleukin-10) or block their receptors, antigen-pulsed syngeneic dendritic cells, or biological products like Pam3Cys (TLR ligand) has already been shown as a prospective treatment of the disease. This review addresses VL treatment, particularly immunotherapy and/or immunochemotherapy as an alternative to conventional drug treatment in experimental models, canine VL, and human disease.
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Affiliation(s)
- Bruno Mendes Roatt
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto , Ouro Preto , Brazil ; Laboratório de Pesquisas Clínicas, Ciências Farmacêuticas, Escola de Farmácia, Universidade Federal de Ouro Preto , Ouro Preto , Brazil ; Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais , Belo Horizonte , Brazil
| | | | - Wendel Coura-Vital
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto , Ouro Preto , Brazil ; Laboratório de Pesquisas Clínicas, Ciências Farmacêuticas, Escola de Farmácia, Universidade Federal de Ouro Preto , Ouro Preto , Brazil
| | - Henrique Gama Ker
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto , Ouro Preto , Brazil ; Laboratório de Pesquisas Clínicas, Ciências Farmacêuticas, Escola de Farmácia, Universidade Federal de Ouro Preto , Ouro Preto , Brazil
| | - Nádia das Dores Moreira
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto , Ouro Preto , Brazil
| | - Juliana Vitoriano-Souza
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto , Ouro Preto , Brazil
| | - Rodolfo Cordeiro Giunchetti
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto , Ouro Preto , Brazil ; Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Cláudia Martins Carneiro
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto , Ouro Preto , Brazil ; Laboratório de Pesquisas Clínicas, Ciências Farmacêuticas, Escola de Farmácia, Universidade Federal de Ouro Preto , Ouro Preto , Brazil
| | - Alexandre Barbosa Reis
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto , Ouro Preto , Brazil ; Laboratório de Pesquisas Clínicas, Ciências Farmacêuticas, Escola de Farmácia, Universidade Federal de Ouro Preto , Ouro Preto , Brazil ; Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais , Belo Horizonte , Brazil
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In vitro drug susceptibility of Leishmania infantum isolated from humans and dogs. Exp Parasitol 2013; 135:36-41. [PMID: 23747751 DOI: 10.1016/j.exppara.2013.05.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 05/25/2013] [Accepted: 05/28/2013] [Indexed: 11/24/2022]
Abstract
Visceral leishmaniasis (VL) caused by parasites of Leishmania donovani complex is a severe human disease which often leads to death if left untreated. Domestic dogs are the main reservoir hosts for zoonotic human visceral infection caused by Leishmania infantum. In the absence of effective human and dog vaccines, the only feasible way to treat and control leishmaniasis is through the use of suitable medications. To know the drug susceptibility of human and canine Leishmania strains from Lisbon-Portugal, a study on a panel of strains was conducted by testing the susceptibility of promastigotes and intracellular amastigotes to the common drugs used in canine leishmaniasis (CanL) and human VL (meglumine antimoniate, amphotericin B, miltefosine and allopurinol). Although a high heterogeneity of susceptibilities was obtained to each drug on both axenic promastigote and intracellular amastigote assays, intracellular amastigotes system correlated better with treatment outcome. Parasites isolated from the refractory human case were the least susceptible to the drugs used highlighting that the emergence of cross-resistance to the drugs available for human therapy should not be neglected. Furthermore, parasites isolated from dogs showed low susceptibility to the main drugs used in CanL treatment. Our results focus the importance of reducing/avoiding the emergence and spread of resistant parasites in the canine and human populations, a factor that requires special consideration when dogs are treated using the same available anti-Leishmania drugs for human VL. In addition, efforts should be made in order to standardize the conditions used to test drug susceptibility (methodologies, drug formulations and media) in order to compare results between laboratories.
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