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Hendrickx S, Boulet G, Mondelaers A, Dujardin JC, Rijal S, Lachaud L, Cos P, Delputte P, Maes L. Experimental selection of paromomycin and miltefosine resistance in intracellular amastigotes of Leishmania donovani and L. infantum. Parasitol Res 2014; 113:1875-81. [PMID: 24615359 DOI: 10.1007/s00436-014-3835-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 02/21/2014] [Indexed: 01/01/2023]
Abstract
Although widespread resistance of Leishmania donovani and L. infantum against miltefosine (MIL) and paromomycin (PMM) has not yet been demonstrated, both run the risk of resistance selection. Unraveling the dynamics and mechanisms of resistance development is key to preserve drug efficacy in the field. In this study, resistance against PMM and MIL was experimentally selected in vitro in intracellular amastigotes of several strains of both species with different antimony susceptibility background. To monitor amastigote susceptibility, microscopic determination of IC50-values and promastigote back-transformation assays were performed. Both techniques were also used to evaluate the susceptibility of field isolates from MIL-relapse patients. PMM-resistance could readily be selected in all species/strains, although promastigotes remained fully PMM-susceptible. Successful MIL-resistance selection was demonstrated only by promastigote back-transformation at increasing MIL-concentrations upon successive selection cycles. Important to note is that amastigotes with the MIL-resistant phenotype could not be visualized after Giemsa staining; hence, MIL-IC50-values showed no shift. The same phenomenon was observed in a set of recent clinical isolates from MIL-relapse patients. This study clearly endorses the need to use intracellular amastigotes for PMM- and MIL-susceptibility testing. When monitoring MIL-resistance, promastigote back-transformation should be used instead of the standard Giemsa staining. In-depth exploration of the mechanistic background of this finding is warranted.
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Affiliation(s)
- S Hendrickx
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
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Kulshrestha A, Sharma V, Singh R, Salotra P. Comparative transcript expression analysis of miltefosine-sensitive and miltefosine-resistant Leishmania donovani. Parasitol Res 2014; 113:1171-84. [PMID: 24449447 DOI: 10.1007/s00436-014-3755-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 01/03/2014] [Indexed: 12/21/2022]
Abstract
Leishmania donovani is the causative agent of anthroponotic visceral leishmaniasis in the Indian subcontinent. Oral miltefosine therapy has recently replaced antimonials in endemic areas. However, the drug is at risk of emergence of resistance due to unrestricted use, and, already, there are indications towards decline in treatment efficacy. Hence, understanding the mechanism of miltefosine resistance in the parasite is crucial. We employed genomic microarray analysis to compare the gene expression patterns of miltefosine-resistant and miltefosine-sensitive L. donovani. Three hundred eleven genes, representing ∼3.9% of the total Leishmania genome, belonging to various functional categories including metabolic pathways, transporters, and cellular components, were differentially expressed in miltefosine-resistant parasite. Results in the present study highlighted the probable mechanisms by which the parasite sustains miltefosine pressure including (1) compromised DNA replication/repair mechanism, (2) reduced protein synthesis and degradation, (3) altered energy utilization via increased lipid degradation, (4) increased ABC 1-mediated drug efflux, and (5) increased antioxidant defense mechanism via elevated trypanothione metabolism. The study provided the comprehensive insight into the underlying mechanism of miltefosine resistance in L. donovani that may be useful to design strategies to increase lifespan of this important oral antileishmanial drug.
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Affiliation(s)
- Arpita Kulshrestha
- National Institute of Pathology (ICMR), Safdarjung Hospital Campus, New Delhi, 110029, India
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Bottieau E, Vekemans M, Van Gompel A. Therapy of vector-borne protozoan infections in nonendemic settings. Expert Rev Anti Infect Ther 2014; 9:583-608. [DOI: 10.1586/eri.11.32] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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54
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Drug resistance in leishmaniasis: current drug-delivery systems and future perspectives. Future Med Chem 2013; 5:1877-88. [DOI: 10.4155/fmc.13.143] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Leishmaniasis is a complex of diseases with numerous clinical manifestations for instance harshness from skin lesions to severe disfigurement and chronic systemic infection in the liver and spleen. So far, the most classical leishmaniasis therapy, despite its documented toxicities, remains pentavalent antimonial compounds. The arvailable therapeutic modalities for leishmaniasis are overwhelmed with resistance to leishmaniasis therapy. Mechanisms of classical drug resistance are often related with the lower drug uptake, increased efflux, the faster drug metabolism, drug target modifications and over-expression of drug transporters. The high prevalence of leishmaniasis and the appearance of resistance to classical drugs reveal the demand to develop and explore novel, less toxic, low cost and more promising therapeutic modalities. The review describes the mechanisms of classical drug resistance and potential drug targets in Leishmania infection. Moreover, current drug-delivery systems and future perspectives towards Leishmaniasis treatment are also covered.
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Das M, Saudagar P, Sundar S, Dubey VK. Miltefosine-unresponsiveLeishmania donovanihas a greater ability than miltefosine-responsiveL. donovanito resist reactive oxygen species. FEBS J 2013; 280:4807-15. [DOI: 10.1111/febs.12449] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 06/21/2013] [Accepted: 07/19/2013] [Indexed: 01/29/2023]
Affiliation(s)
- Mousumi Das
- Department of Biotechnology; Indian Institute of Technology Guwahati; Assam India
| | - Prakash Saudagar
- Department of Biotechnology; Indian Institute of Technology Guwahati; Assam India
| | - Shyam Sundar
- Institute of Medical Sciences; Banaras Hindu University; Varanasi India
| | - Vikash K. Dubey
- Department of Biotechnology; Indian Institute of Technology Guwahati; Assam India
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Strategies for the design of orally bioavailable antileishmanial treatments. Int J Pharm 2013; 454:539-52. [PMID: 23871737 DOI: 10.1016/j.ijpharm.2013.07.035] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 07/08/2013] [Accepted: 07/10/2013] [Indexed: 12/21/2022]
Abstract
Leishmaniasis is one of the six major tropical diseases targeted by the World Health Organization. The most serious, life-threatening form is visceral leishmaniasis (VL). No vaccine is yet available for human use and chemotherapy is the main mean of dealing with this disease. This review focuses on the development of drug delivery systems (DDS) for treatment of leishmaniasis. After an overview of the significance of leishmaniasis in 2013, current chemotherapy and its limitations are considered, leading to possible strategies to improve the treatment of VL: new drugs, combinations of existing drugs and DDS, particularly for oral administration. Nanostructured biomaterials such as lipid-based or polymeric nanoparticles have unique physicochemical properties, ultra-small and controllable size, large surface area to mass ratio and the possibility of surface modification which can be used to advantage for the oral administration of antileishmanial drugs. They can improve the rate of dissolution of poorly water-soluble drugs, increase intestinal residence time by bioadhesion and, especially when lipid additives are used, influence the route and efficiency of absorption. These recent advances in this very active field should lead to better management of this serious disease.
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García-Hernández R, Manzano JI, Castanys S, Gamarro F. Leishmania donovani develops resistance to drug combinations. PLoS Negl Trop Dis 2012; 6:e1974. [PMID: 23285310 PMCID: PMC3527373 DOI: 10.1371/journal.pntd.0001974] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 11/03/2012] [Indexed: 01/31/2023] Open
Abstract
Drug combinations for the treatment of leishmaniasis represent a promising and challenging chemotherapeutic strategy that has recently been implemented in different endemic areas. However, the vast majority of studies undertaken to date have ignored the potential risk that Leishmania parasites could develop resistance to the different drugs used in such combinations. As a result, this study was designed to elucidate the ability of Leishmania donovani to develop experimental resistance to anti-leishmanial drug combinations. The induction of resistance to amphotericin B/miltefosine, amphotericin B/paromomycin, amphotericin B/SbIII, miltefosine/paromomycin, and SbIII/paromomycin was determined using a step-wise adaptation process to increasing drug concentrations. Intracellular amastigotes resistant to these drug combinations were obtained from resistant L. donovani promastigote forms, and the thiol and ATP levels and the mitochondrial membrane potential of the resistant lines were analysed. Resistance to drug combinations was obtained after 10 weeks and remained in the intracellular amastigotes. Additionally, this resistance proved to be unstable. More importantly, we observed that promastigotes/amastigotes resistant to one drug combination showed a marked cross-resistant profile to other anti-leishmanial drugs. Additionally, the thiol levels increased in resistant lines that remained protected against the drug-induced loss of ATP and mitochondrial membrane potential. We have therefore demonstrated that different resistance patterns can be obtained in L. donovani depending upon the drug combinations used. Resistance to the combinations miltefosine/paromomycin and SbIII/paromomycin is easily obtained experimentally. These results have been validated in intracellular amastigotes, and have important relevance for ensuring the long-term efficacy of drug combinations. Leishmania is a protozoan parasite that infects human macrophages to produce the neglected tropical disease known as leishmaniasis. Chemotherapy is currently the only treatment option for leishmaniasis. First-line therapies include pentavalent antimonials, except in some regions in the Indian subcontinent, the liposomal formulation of amphotericin B, miltefosine and paromomycin. The WHO has recently recommended a combined therapy in order to extend the life expectancy of these compounds. However, resistance could be induced in Leishmania if this approach is not applied in a controlled and regulated way, thus resulting in a rapid loss of efficacy of not one but two therapeutic options. In light of this, we have designed relevant experimental studies in order to determine whether Leishmania parasites are able to develop resistance to the different potential anti-leishmanial drug combinations that will be used in the near future. The results obtained could help us to predict the success of drug combination therapy. Experimental resistance of Leishmania donovani promastigotes to drug combinations was obtained after 10 weeks and remained in the intracellular amastigotes. We therefore conclude that L. donovani can easily develop resistance to drug combinations mainly miltefosine/paromomycin and SbIII/paromomycin. These results have been validated in intracellular amastigotes and are of considerable interest for future prediction of the success of drug combination therapy.
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Affiliation(s)
- Raquel García-Hernández
- Instituto de Parasitología y Biomedicina “López-Neyra”, IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
| | - José Ignacio Manzano
- Instituto de Parasitología y Biomedicina “López-Neyra”, IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
| | - Santiago Castanys
- Instituto de Parasitología y Biomedicina “López-Neyra”, IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
| | - Francisco Gamarro
- Instituto de Parasitología y Biomedicina “López-Neyra”, IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
- * E-mail:
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Andrade-Neto VV, Matos-Guedes HLD, Gomes DCDO, Canto-Cavalheiro MMD, Rossi-Bergmann B, Torres-Santos EC. The stepwise selection for ketoconazole resistance induces upregulation of C14-demethylase (CYP51) in Leishmania amazonensis. Mem Inst Oswaldo Cruz 2012; 107:416-9. [PMID: 22510839 DOI: 10.1590/s0074-02762012000300018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 11/07/2011] [Indexed: 11/21/2022] Open
Abstract
Ketoconazole is a clinically safe antifungal agent that also inhibits the growth of Leishmania spp. A study was undertaken to determine whether Leishmania parasites are prone to becoming resistant to ketoconazole by upregulating C14-demethylase after stepwise pharmacological pressure. Leishmania amazonensis promastigotes [inhibitory concentration (IC)₅₀ = 2 µM] were subjected to stepwise selection with ketoconazole and two resistant lines were obtained, La8 (IC₅₀ = 8 µM) and La10 (IC₅₀ = 10 µM). As a result, we found that the resistance level was directly proportional to the C14-demethylase mRNA expression level; we also observed that expression levels were six and 12 times higher in La8 and La10, respectively. This is the first demonstration that L. amazonensis can up-regulate C14-demethylase in response to drug pressure and this report contributes to the understanding of the mechanisms of parasite resistance.
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Affiliation(s)
- Valter Viana Andrade-Neto
- Laboratório de Bioquímica de Tripanosomatídeos, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro, RJ, Brasil
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59
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Kulshrestha A, Bhandari V, Mukhopadhyay R, Ramesh V, Sundar S, Maes L, Dujardin JC, Roy S, Salotra P. Validation of a simple resazurin-based promastigote assay for the routine monitoring of miltefosine susceptibility in clinical isolates of Leishmania donovani. Parasitol Res 2012; 112:825-8. [DOI: 10.1007/s00436-012-3212-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 11/15/2012] [Indexed: 11/30/2022]
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Uranw S, Ostyn B, Dorlo TPC, Hasker E, Dujardin B, Dujardin JC, Rijal S, Boelaert M. Adherence to miltefosine treatment for visceral leishmaniasis under routine conditions in Nepal. Trop Med Int Health 2012. [PMID: 23199340 DOI: 10.1111/tmi.12025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To assess patient adherence to unsupervised single-drug miltefosine treatment for visceral leishmaniasis and to identify the factors influencing adherence. METHODS This is a prospective cohort study of 171 patients with Visceral leishmaniasis (VL) in three healthcare settings in Nepal. Adherence was assessed through pill count, checking of treatment cards and adherence questionnaires, as well as miltefosine concentration measurements at the end of treatment. Poor adherence was defined as less than 90% of required capsules taken. RESULTS Patient adherence to miltefosine was 83%. Predictors of adherence were being the male sex (OR = 2.60, 95% CI 1.02-6.67) and knowing the duration of treatment (OR = 3.05, 95% CI 1.16-8.04). Adherence was also better for patients who were literate and knew the side effects of treatment. Gastrointestinal side effects and negligence after the resolution of clinical symptoms of VL were the main reasons for poor adherence. Poor adherence was associated (though not statistically significant) with future relapse. CONCLUSION Effective counselling during the treatment, a short take-home message on VL and on side effects and action of miltefosine, and follow-up visits are the best way to prevent poor adherence. Single end-of-treatment measurements of miltefosine concentrations as objective assessment of adherence would only be useful in addition to the subjective assessments when substantial doses of miltefosine have been missed.
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Affiliation(s)
- Surendra Uranw
- Department of Internal Medicine, B.P. Koirala Institute of Health Sciences, Ghopa, Dharan, Nepal
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61
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Cojean S, Houzé S, Haouchine D, Huteau F, Lariven S, Hubert V, Michard F, Bories C, Pratlong F, Le Bras J, Loiseau PM, Matheron S. Leishmania resistance to miltefosine associated with genetic marker. Emerg Infect Dis 2012; 18:704-6. [PMID: 22469394 PMCID: PMC3309694 DOI: 10.3201/eid1804.110841] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Dorlo TPC, Balasegaram M, Beijnen JH, de Vries PJ. Miltefosine: a review of its pharmacology and therapeutic efficacy in the treatment of leishmaniasis. J Antimicrob Chemother 2012; 67:2576-97. [PMID: 22833634 DOI: 10.1093/jac/dks275] [Citation(s) in RCA: 501] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Miltefosine is an alkylphosphocholine drug with demonstrated activity against various parasite species and cancer cells as well as some pathogenic bacteria and fungi. For 10 years it has been licensed in India for the treatment of visceral leishmaniasis (VL), a fatal neglected parasitic disease. It is the first and still the only oral drug that can be used to treat VL and cutaneous leishmaniasis (CL). The standard 28 day miltefosine monotherapy regimen is well tolerated, except for mild gastrointestinal side effects, although its teratogenic potential severely hampers its general use in the clinic and roll-out in national elimination programmes. The pharmacokinetics of miltefosine are mainly characterized by its long residence time in the body, resulting in extensive drug accumulation during treatment and long elimination half-lives. At the moment, different combination therapy strategies encompassing miltefosine are being tested in multiple controlled clinical trials in various geographical areas of endemicity, both in South Asia and East Africa. We here review the most salient pre-clinical and clinical pharmacological aspects of miltefosine, its mechanism of action against Leishmania parasites and other pathogens, and provide a systematic overview of the efficacy and safety data from all clinical trials of miltefosine, either alone or in combination, in the treatment of VL and CL.
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Affiliation(s)
- Thomas P C Dorlo
- Center for Tropical Medicine and Travel Medicine, Division of Infectious Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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63
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Campos Vieira N, Vacus J, Fournet A, Baudouin R, Bories C, Séon-Méniel B, Figadère B, Loiseau PM. Antileishmanial activity of a formulation of 2-n-propylquinoline by oral route in mice model. Parasite 2012; 18:333-6. [PMID: 22091464 PMCID: PMC3677589 DOI: 10.1051/parasite/2011184333] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
2-n-propylquinoline is presently a drug-candidate for the treatment of visceral leishmaniosis in pre-clinical development. As this compound is in an oily state, it needs to be formulated and the objectives of this study are: to prepare a formulation; to demonstrate that the new salted formulation did not alter the activity of the active ingredient; and finally, that this activity was quite good compared to the reference oral drug, miltefosine. Therefore, a 2-n-propylquinoline formulation, as camphorsulfonic salt, was prepared and characterised. On the Leishmania donovani / Balb/c mice model, a treatment by oral route at 60 μmoles/kg/day for ten consecutive days with this formulation was compared to 2-n-propylquinoline alone and to miltefosine, the oral reference drug. The salt formulation did not alter the activity of the 2-n-propylquinoline. The formulation reduced the parasite burden of 76% compared to 89% for miltefosine (not significant). The characteristics of this formulation results in a suitable drugability of 2-n-propylquinoline for further studies.
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Affiliation(s)
- N Campos Vieira
- Groupe Chimiothérapie Antiparasitaire, UMR 8076 CNRS, Faculté de Pharmacie, Université Paris-Sud, Rue Jean-Baptiste, 92296 Châtenay-Malabry Cedex, France
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Palladium(II) imine ligands cyclometallated complexes with a potential leishmanicidal activity on Leishmania (L.) amazonensis. Med Chem Res 2012. [DOI: 10.1007/s00044-012-0095-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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65
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Bhandari V, Kulshrestha A, Deep DK, Stark O, Prajapati VK, Ramesh V, Sundar S, Schonian G, Dujardin JC, Salotra P. Drug susceptibility in Leishmania isolates following miltefosine treatment in cases of visceral leishmaniasis and post kala-azar dermal leishmaniasis. PLoS Negl Trop Dis 2012; 6:e1657. [PMID: 22629478 PMCID: PMC3358331 DOI: 10.1371/journal.pntd.0001657] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 04/11/2012] [Indexed: 11/10/2022] Open
Abstract
Background With widespread resistance to antimonials in Visceral Leishmaniasis (VL) in the Indian subcontinent, Miltefosine (MIL) has been introduced as the first line therapy. Surveillance of MIL susceptibility in natural populations of Leishmania donovani is vital to preserve it and support the VL elimination program. Methodology and Principal Findings We measured in vitro susceptibility towards MIL and paromomycin (PMM) in L. donovani isolated from VL and PKDL, pre- and post-treatment cases, using an amastigote-macrophage model. MIL susceptibility of post-treatment isolates from cured VL cases (n = 13, mean IC50±SD = 2.43±1.44 µM), was comparable (p>0.05) whereas that from relapses (n = 3, mean IC50 = 4.72±1.99 µM) was significantly higher (p = 0.04) to that of the pre-treatment group (n = 6, mean IC50 = 1.86±0.75 µM). In PKDL, post-treatment isolates (n = 3, mean IC50 = 16.13±2.64 µM) exhibited significantly lower susceptibility (p = 0.03) than pre-treatment isolates (n = 5, mean IC50 = 8.63±0.94 µM). Overall, PKDL isolates (n = 8, mean IC50 = 11.45±4.19 µM) exhibited significantly higher tolerance (p<0.0001) to MIL than VL isolates (n = 22, mean IC50 = 2.58±1.58 µM). Point mutations in the miltefosine transporter (LdMT) and its beta subunit (LdRos3) genes previously reported in parasites with experimentally induced MIL resistance were not present in the clinical isolates. Further, the mRNA expression profile of these genes was comparable in the pre- and post-treatment isolates. Parasite isolates from VL and PKDL cases were uniformly susceptible to PMM with respective mean IC50 = 7.05±2.24 µM and 6.18±1.51 µM. Conclusion The in vitro susceptibility of VL isolates remained unchanged at the end of MIL treatment; however, isolates from relapsed VL and PKDL cases had lower susceptibility than the pre-treatment isolates. PKDL isolates were more tolerant towards MIL in comparison with VL isolates. All parasite isolates were uniformly susceptible to PMM. Mutations in the LdMT and LdRos3 genes as well as changes in the expression of these genes previously correlated with experimental resistance to MIL could not be verified for the field isolates. Resistance to antimonials has emerged as a major hurdle to the treatment and control of VL and led to the introduction of Miltefosine as first line treatment in the Indian subcontinent. MIL is an oral drug with a long half-life, and it is feared that resistance may emerge rapidly, threatening control efforts under the VL elimination program. There is an urgent need for monitoring treatment efficacy and emergence of drug resistance in the field. In a set of VL/PKDL cases recruited for MIL treatment, we observed comparable drug susceptibility in pre- and post-treatment isolates from cured VL patients while MIL susceptibility was significantly reduced in isolates from VL relapse and PKDL cases. The PKDL isolates showed higher tolerance to MIL as compared to VL isolates. Both VL and PKDL isolates were uniformly susceptible to PMM. MIL transporter genes LdMT/LdRos3 were previously reported as potential resistance markers in strains in which MIL resistance was experimentally induced. The point mutations and the down-regulated expression of these transporters observed in vitro could, however, not be verified in natural populations of parasites. LdMT/LdRos3 genes therefore, do not appear to be suitable markers so far for monitoring drug susceptibility in clinical leishmanial isolates.
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Affiliation(s)
- Vasundhra Bhandari
- National Institute of Pathology, Indian Council of Medical Research, Safdarjung Hospital Campus, New Delhi, India
| | - Arpita Kulshrestha
- National Institute of Pathology, Indian Council of Medical Research, Safdarjung Hospital Campus, New Delhi, India
| | - Deepak Kumar Deep
- National Institute of Pathology, Indian Council of Medical Research, Safdarjung Hospital Campus, New Delhi, India
| | - Olivia Stark
- Institute of Microbiology and Hygiene, Charite University Medicine Berlin, Berlin, Germany
| | | | - V. Ramesh
- Department of Dermatology, Safdarjung Hospital, New Delhi, India
| | - Shyam Sundar
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Gabriele Schonian
- Institute of Microbiology and Hygiene, Charite University Medicine Berlin, Berlin, Germany
| | - Jean Claude Dujardin
- Unit of Molecular Parasitology, Department of Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
| | - Poonam Salotra
- National Institute of Pathology, Indian Council of Medical Research, Safdarjung Hospital Campus, New Delhi, India
- * E-mail:
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Varela-M RE, Villa-Pulgarin JA, Yepes E, Müller I, Modolell M, Muñoz DL, Robledo SM, Muskus CE, López-Abán J, Muro A, Vélez ID, Mollinedo F. In vitro and in vivo efficacy of ether lipid edelfosine against Leishmania spp. and SbV-resistant parasites. PLoS Negl Trop Dis 2012; 6:e1612. [PMID: 22506086 PMCID: PMC3323514 DOI: 10.1371/journal.pntd.0001612] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 02/27/2012] [Indexed: 01/05/2023] Open
Abstract
Background The leishmaniases are a complex of neglected tropical diseases caused by more than 20 Leishmania parasite species, for which available therapeutic arsenal is scarce and unsatisfactory. Pentavalent antimonials (SbV) are currently the first-line pharmacologic therapy for leishmaniasis worldwide, but resistance to these compounds is increasingly reported. Alkyl-lysophospoholipid analogs (ALPs) constitute a family of compounds with antileishmanial activity, and one of its members, miltefosine, has been approved as the first oral treatment for visceral and cutaneous leishmaniasis. However, its clinical use can be challenged by less impressive efficiency in patients infected with some Leishmania species, including L. braziliensis and L. mexicana, and by proneness to develop drug resistance in vitro. Methodology/Principal Findings We found that ALPs ranked edelfosine>perifosine>miltefosine>erucylphosphocholine for their antileishmanial activity and capacity to promote apoptosis-like parasitic cell death in promastigote and amastigote forms of distinct Leishmania spp., as assessed by proliferation and flow cytometry assays. Effective antileishmanial ALP concentrations were dependent on both the parasite species and their development stage. Edelfosine accumulated in and killed intracellular Leishmania parasites within macrophages. In vivo antileishmanial activity was demonstrated following oral treatment with edelfosine of mice and hamsters infected with L. major, L. panamensis or L. braziliensis, without any significant side-effect. Edelfosine also killed SbV-resistant Leishmania parasites in in vitro and in vivo assays, and required longer incubation times than miltefosine to generate drug resistance. Conclusions/Significance Our data reveal that edelfosine is the most potent ALP in killing different Leishmania spp., and it is less prone to lead to drug resistance development than miltefosine. Edelfosine is effective in killing Leishmania in culture and within macrophages, as well as in animal models infected with different Leishmania spp. and SbV-resistant parasites. Our results indicate that edelfosine is a promising orally administered antileishmanial drug for clinical evaluation. Leishmaniasis represents a major international health problem, has a high morbidity and mortality rate, and is classified as an emerging and uncontrolled disease by the World Health Organization. The migration of population from endemic to nonendemic areas, and tourist activities in endemic regions are spreading the disease to new areas. Unfortunately, treatment of leishmaniasis is far from satisfactory, with only a few drugs available that show significant side-effects. Here, we show in vitro and in vivo evidence for the antileishmanial activity of the ether phospholipid edelfosine, being effective against a wide number of Leishmania spp. causing cutaneous, mucocutaneous and visceral leishmaniasis. Our experimental mouse and hamster models demonstrated not only a significant antileishmanial activity of edelfosine oral administration against different wild-type Leishmania spp., but also against parasites resistant to pentavalent antimonials, which constitute the first line of treatment worldwide. In addition, edelfosine exerted a higher antileishmanial activity and a lower proneness to generate drug resistance than miltefosine, the first drug against leishmaniasis that can be administered orally. These data, together with our previous findings, showing an anti-inflammatory action and a very low toxicity profile, suggest that edelfosine is a promising orally administered drug for leishmaniasis, thus warranting clinical evaluation.
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Affiliation(s)
- Rubén E. Varela-M
- Instituto de Biología Molecular y Celular del Cáncer, Centro de Investigación del Cáncer, CSIC-Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
- APOINTECH, Centro Hispano-Luso de Investigaciones Agrarias, Parque Científico de la Universidad de Salamanca, Villamayor, Salamanca, Spain
| | - Janny A. Villa-Pulgarin
- Instituto de Biología Molecular y Celular del Cáncer, Centro de Investigación del Cáncer, CSIC-Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
- APOINTECH, Centro Hispano-Luso de Investigaciones Agrarias, Parque Científico de la Universidad de Salamanca, Villamayor, Salamanca, Spain
| | - Edward Yepes
- APOINTECH, Centro Hispano-Luso de Investigaciones Agrarias, Parque Científico de la Universidad de Salamanca, Villamayor, Salamanca, Spain
- Laboratorio de Inmunología Parasitaria y Molecular, CIETUS, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Ingrid Müller
- Department of Medicine, Section of Immunology, St. Mary's Campus, Imperial College London, London, United Kingdom
| | - Manuel Modolell
- Department of Cellular Immunology, Max-Planck-Institut für Immunbiologie, Freiburg, Germany
| | - Diana L. Muñoz
- Programa de Estudio y Control de Enfermedades Tropicales, Universidad de Antioquia, Medellín, Colombia
| | - Sara M. Robledo
- Programa de Estudio y Control de Enfermedades Tropicales, Universidad de Antioquia, Medellín, Colombia
| | - Carlos E. Muskus
- Programa de Estudio y Control de Enfermedades Tropicales, Universidad de Antioquia, Medellín, Colombia
| | - Julio López-Abán
- Laboratorio de Inmunología Parasitaria y Molecular, CIETUS, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Antonio Muro
- Laboratorio de Inmunología Parasitaria y Molecular, CIETUS, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Iván D. Vélez
- Programa de Estudio y Control de Enfermedades Tropicales, Universidad de Antioquia, Medellín, Colombia
| | - Faustino Mollinedo
- Instituto de Biología Molecular y Celular del Cáncer, Centro de Investigación del Cáncer, CSIC-Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
- * E-mail:
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Coelho AC, Boisvert S, Mukherjee A, Leprohon P, Corbeil J, Ouellette M. Multiple mutations in heterogeneous miltefosine-resistant Leishmania major population as determined by whole genome sequencing. PLoS Negl Trop Dis 2012; 6:e1512. [PMID: 22348164 PMCID: PMC3279362 DOI: 10.1371/journal.pntd.0001512] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 12/20/2011] [Indexed: 01/11/2023] Open
Abstract
Background Miltefosine (MF) is the first oral compound used in the chemotherapy against leishmaniasis. Since the mechanism of action of this drug and the targets of MF in Leishmania are unclear, we generated in a step-by-step manner Leishmania major promastigote mutants highly resistant to MF. Two of the mutants were submitted to a short-read whole genome sequencing for identifying potential genes associated with MF resistance. Methods/Principal Findings Analysis of the genome assemblies revealed several independent point mutations in a P-type ATPase involved in phospholipid translocation. Mutations in two other proteins—pyridoxal kinase and α-adaptin like protein—were also observed in independent mutants. The role of these proteins in the MF resistance was evaluated by gene transfection and gene disruption and both the P-type ATPase and pyridoxal kinase were implicated in MF susceptibility. The study also highlighted that resistance can be highly heterogeneous at the population level with individual clones derived from this population differing both in terms of genotypes but also susceptibility phenotypes. Conclusions/Significance Whole genome sequencing was used to pinpoint known and new resistance markers associated with MF resistance in the protozoan parasite Leishmania. The study also demonstrated the polyclonal nature of a resistant population with individual cells with varying susceptibilities and genotypes. Leishmania spp. are parasitic protozoa responsible for a spectrum of diseases known as leishmaniasis. There are few drugs available for the treatment of these diseases, and miltefosine is the first oral drug used in treatment of visceral leishmaniasis, a form of the disease that can be lethal if not treated. In this study, we seek to understand the mechanism of action and identify targets of the drug by generating promastigote mutants highly resistant to miltefosine. Two independent mutants were submitted to short read whole genome sequencing. Genome analysis of these mutants has permitted us to identify point mutations in three genes (P-type ATPase, pyridoxal kinase and α-adaptin like protein) that were also present in other independent miltefosine resistant mutants. Some of the new genes identified here could be useful as potential markers for miltefosine resistance in Leishmania. Moreover, our approach has permitted us to highlight that resistance can be highly heterogeneous at the population level with individual clones derived from this population differing both in terms of genotypes but also susceptibility phenotypes. This may have practical applications while studying resistance.
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Affiliation(s)
- Adriano C. Coelho
- Centre de Recherche en Infectiologie, Université Laval, Québec, Canada
| | | | - Angana Mukherjee
- Centre de Recherche en Infectiologie, Université Laval, Québec, Canada
| | - Philippe Leprohon
- Centre de Recherche en Infectiologie, Université Laval, Québec, Canada
| | - Jacques Corbeil
- Centre de Recherche en Infectiologie, Université Laval, Québec, Canada
| | - Marc Ouellette
- Centre de Recherche en Infectiologie, Université Laval, Québec, Canada
- * E-mail:
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Vanaerschot M, De Doncker S, Rijal S, Maes L, Dujardin JC, Decuypere S. Antimonial resistance in Leishmania donovani is associated with increased in vivo parasite burden. PLoS One 2011; 6:e23120. [PMID: 21829701 PMCID: PMC3148249 DOI: 10.1371/journal.pone.0023120] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 07/08/2011] [Indexed: 11/18/2022] Open
Abstract
Leishmania donovani is an intracellular protozoan parasite that causes visceral leishmaniasis (VL). Antimonials (SSG) have long been the first-line treatment against VL, but have now been replaced by miltefosine (MIL) in the Indian subcontinent due to the emergence of SSG-resistance. Our previous study hypothesised that SSG-resistant L. donovani might have increased in vivo survival skills which could affect the efficacy of other treatments such as MIL. The present study attempts to validate these hypotheses. Fourteen strains derived from Nepalese clinical isolates with documented SSG-susceptibility were infected in BALB/c mice to study their survival capacity in drug free conditions (non-treated mice) and in MIL-treated mice. SSG-resistant parasites caused a significant higher in vivo parasite load compared to SSG-sensitive parasites. However, this did not seem to affect the strains' response to MIL-treatment since parasites from both phenotypes responded equally well to in vivo MIL exposure. We conclude that there is a positive association between SSG-resistance and in vivo survival skills in our sample of L. donovani strains which could suggest a higher virulence of SSG-R strains compared to SSG-S strains. These greater in vivo survival skills of SSG-R parasites do not seem to directly affect their susceptibility to MIL. However, it cannot be excluded that repeated MIL exposure will elicit different adaptations in these SSG-R parasites with superior survival skills compared to the SSG-S parasites. Our results therefore highlight the need to closely monitor drug efficacy in the field, especially in the context of the Kala-azar elimination programme ongoing in the Indian subcontinent.
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Affiliation(s)
- Manu Vanaerschot
- Unit of Molecular Parasitology, Department of Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
- Laboratory for Microbiology, Parasitology and Hygiene, Department of Biomedical Sciences, Antwerp University, Antwerp, Belgium
| | - Simonne De Doncker
- Unit of Molecular Parasitology, Department of Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
| | - Suman Rijal
- Department of Internal Medicine, B.P. Koirala Institute of Health Sciences, Dharan, Nepal
| | - Louis Maes
- Laboratory for Microbiology, Parasitology and Hygiene, Department of Biomedical Sciences, Antwerp University, Antwerp, Belgium
| | - Jean-Claude Dujardin
- Unit of Molecular Parasitology, Department of Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
- Laboratory for Microbiology, Parasitology and Hygiene, Department of Biomedical Sciences, Antwerp University, Antwerp, Belgium
- * E-mail:
| | - Saskia Decuypere
- Unit of Molecular Parasitology, Department of Parasitology, Institute of Tropical Medicine, Antwerp, Belgium
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69
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Antiprotozoal compounds: state of the art and new developments. Int J Antimicrob Agents 2011; 38:118-24. [DOI: 10.1016/j.ijantimicag.2011.03.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2011] [Accepted: 03/08/2011] [Indexed: 11/20/2022]
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Abstract
The treatment options of leishmaniasis are limited and far from satisfactory. For more than 60 years, treatment of leishmaniasis has centered around pentavalent antimonials (Sbv). Widespread misuse has led to the emergence of Sbv resistance in the hyperendemic areas of North Bihar. Other antileishmanials could also face the same fate, especially in the anthroponotic cycle. The HIV/ visceral leishmaniasis (VL) coinfected patients are another potential source for the emergence of drug resistance. At present no molecular markers of resistance are available and the only reliable method for monitoring resistance of isolates is the technically demanding in vitro amastigote-macrophage model. As the armametrium of drugs for leishmaniasis is limited, it is important that effective monitoring of drug use and response should be done to prevent the spread of resistance. Regimens of simultaneous or sequential combinations should be seriously considered to limit the emergence of resistance.
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Affiliation(s)
- Jaya Chakravarty
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi-221 005, India
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71
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Mrva M, Garajová M, Lukáč M, Ondriska F. Weak Cytotoxic Activity of Miltefosine Against Clinical Isolates of Acanthamoeba spp. J Parasitol 2011; 97:538-40. [DOI: 10.1645/ge-2669.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Astelbauer F, Obwaller A, Raninger A, Brem B, Greger H, Duchêne M, Wernsdorfer W, Walochnik J. Anti-leishmanial activity of plant-derived acridones, flavaglines, and sulfur-containing amides. Vector Borne Zoonotic Dis 2011; 11:793-8. [PMID: 21417924 DOI: 10.1089/vbz.2010.0087] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Visceral and cutaneous leishmaniases are an important public health problem in endemic geographic regions in 88 countries worldwide, with around 12 million infected people. Treatment options are limited due to toxicity and teratogenicity of the available drugs, response problems in HIV/Leishmania co-infections, and upcoming resistances. In this study, we investigated the anti-leishmanial activity of 13 plant-derived compounds in vitro aiming to find new drug candidates. Toxicity of the compounds was evaluated in human primary hepatocytes, and hemolytic activity was examined in freshly isolated erythrocytes. Two acridones, 5-hydroxynoracronycine and yukocitrine, two flavaglines, aglafoline and rocaglamide, and the sulfur-containing amide methyldambullin showed promising anti-leishmanial activities with 50% effective concentrations (EC50s) of 34.84, 29.76, 7.45, 16.45, and 6.29 μM, respectively. Hepatotoxic activities of 5-hydroxynoracronycine, yukocitrine, and methyldambullin were significantly lower compared to miltefosine and lower or equal compared to artesunate, whereas the ones of rocaglamide and aglafoline were slightly higher compared to miltefosine and significantly higher compared to artesunate. None of the compounds showed hemolytic activity.
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Affiliation(s)
- Florian Astelbauer
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
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Seifert K. Structures, targets and recent approaches in anti-leishmanial drug discovery and development. THE OPEN MEDICINAL CHEMISTRY JOURNAL 2011; 5:31-9. [PMID: 21629509 PMCID: PMC3103891 DOI: 10.2174/1874104501105010031] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 05/12/2010] [Accepted: 06/20/2010] [Indexed: 11/22/2022]
Abstract
Recent years have seen a significant improvement in available treatment options for leishmaniasis. Two new drugs, miltefosine and paromomycin, have been registered for the treatment of visceral leishmaniasis (VL) in India since 2002. Combination therapy is now explored in clinical trials as a new treatment approach for VL to reduce the length of treatment and potentially prevent selection of resistant parasites. However there is still a need for new drugs due to safety, resistance, stability and cost issues with existing therapies. The search for topical treatments for cutaneous leishmaniasis (CL) is ongoing. This review gives a brief overview of recent developments and approaches in anti-leishmanial drug discovery and development.
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Affiliation(s)
- Karin Seifert
- London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK
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74
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Boelaert M, Meheus F, Robays J, Lutumba P. Socio-economic aspects of neglected diseases: sleeping sickness and visceral leishmaniasis. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2011; 104:535-42. [PMID: 21092391 DOI: 10.1179/136485910x12786389891641] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Several tropical diseases that are essentially poverty-related have recently gained more attention under the label of 'neglected tropical diseases' or NTD. It is estimated that over 1000 million people currently suffer from one or more NTD. Here, the socio-economic aspects of two NTD - human African trypanosomiasis and human visceral leishmaniasis - are reviewed. Both of these diseases affect the poorest of the poor in endemic countries, cause considerable direct and indirect costs (even though the national control programmes tend to provide free care) and push affected households deeper into poverty.
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Affiliation(s)
- M Boelaert
- Epidemiology and Disease Control Unit, Department of Public Health, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium.
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Increased glycolytic ATP synthesis is associated with tafenoquine resistance in Leishmania major. Antimicrob Agents Chemother 2011; 55:1045-52. [PMID: 21199921 DOI: 10.1128/aac.01545-10] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tafenoquine (TFQ), an 8-aminoquinoline used to treat and prevent Plasmodium infections, could represent an alternative therapy for leishmaniasis. Indeed, TFQ has shown significant leishmanicidal activity both in vitro and in vivo, where it targets Leishmania mitochondria and activates a final apoptosis-like process. In order not to jeopardize the life span of this potential antileishmania drug, it is important to determine the likelihood that Leishmania will develop resistance to TFQ and the mechanisms of resistance induced. To address this issue, a TFQ-resistant Leishmania major promastigote line (R4) was selected. This resistance, which is unstable in a drug-free medium (revertant line), was maintained in intramacrophage amastigote forms, and R4 promastigotes were found to be cross-resistant to other 8-aminoquinolines. A decreased TFQ uptake, which is probably associated with an alkalinization of the intracellular pH rather than drug efflux, was observed for both the R4 and revertant lines. TFQ induces a decrease in ATP synthesis in all Leishmania lines, although total ATP levels were maintained at higher values in R4 parasites. In contrast, ATP synthesis by glycolysis was significantly increased in R4 parasites, whereas mitochondrial ATP synthesis was similar to that in wild-type parasites. We therefore conclude that increased glycolytic ATP synthesis is the main mechanism underlying TFQ resistance in Leishmania.
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Meheus F, Balasegaram M, Olliaro P, Sundar S, Rijal S, Faiz MA, Boelaert M. Cost-effectiveness analysis of combination therapies for visceral leishmaniasis in the Indian subcontinent. PLoS Negl Trop Dis 2010; 4. [PMID: 20838649 PMCID: PMC2935395 DOI: 10.1371/journal.pntd.0000818] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 08/12/2010] [Indexed: 11/20/2022] Open
Abstract
Background Visceral leishmaniasis is a systemic parasitic disease that is fatal unless treated. We assessed the cost and cost-effectiveness of alternative strategies for the treatment of visceral leishmaniasis in the Indian subcontinent. In particular we examined whether combination therapies are a cost-effective alternative compared to monotherapies. Methods and Findings We assessed the cost-effectiveness of all possible mono- and combination therapies for the treatment of visceral leishmaniasis in the Indian subcontinent (India, Nepal and Bangladesh) from a societal perspective using a decision analytical model based on a decision tree. Primary data collected in each country was combined with data from the literature and an expert poll (Delphi method). The cost per patient treated and average and incremental cost-effectiveness ratios expressed as cost per death averted were calculated. Extensive sensitivity analysis was done to evaluate the robustness of our estimations and conclusions. With a cost of US$92 per death averted, the combination miltefosine-paromomycin was the most cost-effective treatment strategy. The next best alternative was a combination of liposomal amphotericin B with paromomycin with an incremental cost-effectiveness of $652 per death averted. All other strategies were dominated with the exception of a single dose of 10mg per kg of liposomal amphotericin B. While strategies based on liposomal amphotericin B (AmBisome) were found to be the most effective, its current drug cost of US$20 per vial resulted in a higher average cost-effectiveness. Sensitivity analysis showed the conclusion to be robust to variations in the input parameters over their plausible range. Conclusions Combination treatments are a cost-effective alternative to current monotherapy for VL. Given their expected impact on the emergence of drug resistance, a switch to combination therapy should be considered once final results from clinical trials are available. Visceral leishmaniasis (VL) is a serious health problem in the Indian subcontinent affecting the rural poor. It has a significant economic impact on concerned households. The development of drug resistance is a major problem and threatens control efforts under the VL elimination initiative. With an unprecedented choice of antileishmanial drugs (but no newer compound in clinical development), policies that protect these drugs against the emergence of resistance are required. A possible strategy that has been successfully used for malaria and tuberculosis is the use of combination therapies. This study is the first comprehensive assessment of the cost-effectiveness of all possible mono- and combination therapies for the treatment of visceral leishmaniasis in the Indian subcontinent. The analysis was done from the societal perspective, including both health provider and household costs. The present work shows that combination treatments are a cost-effective alternative to current monotherapy for VL. Given their expected impact on emergence of drug resistance, the use of combination therapy should be considered in the context of the VL elimination programme in the Indian subcontinent.
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Affiliation(s)
- Filip Meheus
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.
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Collaborative actions in anti-trypanosomatid chemotherapy with partners from disease endemic areas. Trends Parasitol 2010; 26:395-403. [DOI: 10.1016/j.pt.2010.04.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Revised: 04/28/2010] [Accepted: 04/29/2010] [Indexed: 11/22/2022]
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Chandra S, Ruhela D, Deb A, Vishwakarma RA. Glycobiology of theLeishmaniaparasite and emerging targets for antileishmanial drug discovery. Expert Opin Ther Targets 2010; 14:739-57. [DOI: 10.1517/14728222.2010.495125] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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79
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Liarte DB, Murta SMF. Selection and phenotype characterization of potassium antimony tartrate-resistant populations of four New World Leishmania species. Parasitol Res 2010; 107:205-12. [PMID: 20372925 DOI: 10.1007/s00436-010-1852-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Accepted: 03/18/2010] [Indexed: 10/19/2022]
Abstract
In the present study, we selected in vitro populations of Leishmania Viannia guyanensis, L.V. braziliensis, L. Leishmania amazonensis and L.L. infantum chagasi that were resistant to potassium antimony tartrate (SbIII). The resistance index of these populations varied from 4- to 20-fold higher than that of their wild-type counterparts. To evaluate the stability of the resistance phenotype, these four resistant populations were passaged 37 to 47 times in a culture medium without SbIII. No change was observed in the resistance indexes of L.V. guyanensis (19-fold) and L.L. infantum chagasi (4-fold). In contrast, a decrease in the resistance index was observed for L.V. braziliensis (from 20- to 10-fold) and L.L. amazonensis (from 6- to 3-fold). None of the antimony-resistant populations exhibited cross-resistance to amphotericin B and miltefosine. However, the resistant populations of L.V. braziliensis, L.L. amazonensis and L.L. infantum chagasi were also resistant to paromomycin. A drastic reduction was observed in the infectivity in mice for the resistant L.V. guyanensis, L.L. amazonensis and L.V. braziliensis populations. The SbIII-resistant phenotype of L.V. braziliensis was stable after one passage in mice. Although the protocol of induction was the same, the SbIII-resistant populations showed different degrees of tolerance, stability, infectivity in mice and cross-resistance to antileishmanial drugs, depending on the Leishmania species.
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Affiliation(s)
- Daniel B Liarte
- Laboratório de Parasitologia Celular e Molecular, Centro de Pesquisas René Rachou-CPqRR/Fiocruz, Av. Augusto de Lima 1715, Caixa Postal 1743, CEP 30190-002, Belo Horizonte, MG, Brazil
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Kumar P, Lodge R, Trudel N, Ouellet M, Ouellette M, Tremblay MJ. Nelfinavir, an HIV-1 protease inhibitor, induces oxidative stress-mediated, caspase-independent apoptosis in Leishmania amastigotes. PLoS Negl Trop Dis 2010; 4:e642. [PMID: 20361030 PMCID: PMC2846936 DOI: 10.1371/journal.pntd.0000642] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Accepted: 02/09/2010] [Indexed: 01/23/2023] Open
Abstract
Background Visceral leishmaniasis has now emerged as an important opportunistic disease in patients coinfected with human immunodeficiency virus type-1 (HIV-1). Although the effectiveness of HIV-1 protease inhibitors, such as nelfinavir, in antiretroviral therapies is well documented, little is known of the impact of these drugs on Leishmania in coinfected individuals. Methodology and Principal Findings Here, we show that nelfinavir generates oxidative stress in the parasite, leading to altered physiological parameters such as an increase in the sub-G1 DNA content, nuclear DNA fragmentation and loss of mitochondrial potential, which are all characteristics of apoptosis. Pretreatment of axenic amastigotes with the caspase inhibitor z-VAD-fmk did not inhibit the increase in sub-G1 DNA content in nelfinavir-treated parasites, suggesting therefore that this antiviral agent does not kill Leishmania amastigotes in a caspase-dependent manner. Furthermore, we observed that the mitochondrial resident protein endonuclease G is involved. We also demonstrate that parasites overexpressing GSH1 (the rate limiting enzyme of glutathione biosynthesis) were more resistant to nelfinavir when compared to untransfected controls. Conclusions and Significance These data suggest that nelfinavir induces oxidative stress in Leishmania amastigotes, culminating in caspase-independent apoptosis, in which DNA is degraded by endonuclease G. This study provides a rationale for future, long-term design of new therapeutic strategies to test nelfinavir as a potential antileishmanial agent as well as for possible future use in Leishmania/HIV-1 coinfections. Visceral leishmaniasis is the most severe form of disease caused by the parasite Leishmania. It is a major concern in South America, Africa, India and the Middle East. Additionally, it has now emerged as an important opportunistic disease in patients coinfected with HIV-1. This is due, in part, to the increasing overlap between urban centers and rural areas endemic for Leishmania. Although more efficient combinatorial antiviral drug regimens for treating HIV-1 infection have been developed, the impact of such therapies on HIV-1/Leishmania coinfection is yet to be explored. In this study, we investigated the effect of nelfinavir, a well-characterized anti-HIV-1 drug, on Leishmania. Treating the parasite with nelfinavir activates events that are hallmarks of programmed cell death (also called apoptosis). Among these are oxidative stress, changes in DNA replication and fragmentation, and release of mitochondrial enzymes. Furthermore, these events occur without the participation of caspases, which are classically linked to apoptosis; however, this atypical apoptosis requires the translocation of endonuclease G from mitochondria to the cytoplasm. These findings provide insights for the design of new anti-parasitic therapies, particularly in the case of Leishmania/HIV-1 coinfections.
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Affiliation(s)
- Pranav Kumar
- Centre de Recherche en Infectiologie, Centre Hospitalier de l'Université Laval, and Département de Microbiologie et Immunologie, Université Laval, Québec, Canada
| | - Robert Lodge
- Centre de Recherche en Infectiologie, Centre Hospitalier de l'Université Laval, and Département de Microbiologie et Immunologie, Université Laval, Québec, Canada
| | - Nathalie Trudel
- Centre de Recherche en Infectiologie, Centre Hospitalier de l'Université Laval, and Département de Microbiologie et Immunologie, Université Laval, Québec, Canada
| | - Michel Ouellet
- Centre de Recherche en Infectiologie, Centre Hospitalier de l'Université Laval, and Département de Microbiologie et Immunologie, Université Laval, Québec, Canada
| | - Marc Ouellette
- Centre de Recherche en Infectiologie, Centre Hospitalier de l'Université Laval, and Département de Microbiologie et Immunologie, Université Laval, Québec, Canada
| | - Michel J. Tremblay
- Centre de Recherche en Infectiologie, Centre Hospitalier de l'Université Laval, and Département de Microbiologie et Immunologie, Université Laval, Québec, Canada
- * E-mail:
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81
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Drug resistance in visceral leishmaniasis. J Biomed Biotechnol 2009; 2010:617521. [PMID: 19888437 PMCID: PMC2771279 DOI: 10.1155/2010/617521] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Revised: 08/10/2009] [Accepted: 08/30/2009] [Indexed: 11/17/2022] Open
Abstract
Visceral leishmaniasis remains a public health problem worldwide. This illness was included by the World Health Organization in the list of neglected tropical diseases targeted for elimination by 2015. The widespread emergence of resistance to pentavalent antimonials in India where half cases occur globally and the unavailability of a vaccine in clinical use constitute major obstacles in achieving of this goal. The last decade new antileishmanials became available, including the oral agent miltefosine. However, in poor endemic countries their wide use was curtailed because of the high costs, and also due to concerns of toxicity and emergence of resistance. Various mechanisms of antileishmanial resistance were identified recently in field isolates. Their elucidation will boost the design of new drugs and the molecular surveillance of resistance. Combination regimens should be evaluated in large trials. Overall, the development of antileishmanials has been generally slow; new drugs are needed. In order to control visceral leishmaniasis worldwide, treatment advances should become affordable in the poorest countries, where they are needed most.
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82
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Ha̧c-Wydro K, Dynarowicz-Ła̧tka P, Żuk R. Langmuir Monolayer Study toward Combined Antileishmanian Therapy Involving Amphotericin B and Edelfosine. J Phys Chem B 2009; 113:14239-46. [DOI: 10.1021/jp9032996] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Katarzyna Ha̧c-Wydro
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland, and M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Kraków, Poland
| | - Patrycja Dynarowicz-Ła̧tka
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland, and M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Kraków, Poland
| | - Radosław Żuk
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland, and M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Kraków, Poland
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83
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Saint-Pierre-Chazalet M, Ben Brahim M, Le Moyec L, Bories C, Rakotomanga M, Loiseau PM. Membrane sterol depletion impairs miltefosine action in wild-type and miltefosine-resistant Leishmania donovani promastigotes. J Antimicrob Chemother 2009; 64:993-1001. [PMID: 19749205 DOI: 10.1093/jac/dkp321] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES This study focuses on the importance of sterols in the action of miltefosine (hexadecylphosphocholine, HePC) against Leishmania donovani. METHODS Plasma membranes of L. donovani promastigotes were depleted of sterol using methyl-beta-cyclodextrin (MCD) and cholesterol oxidase (CH-OX). Sterols were quantified and HePC susceptibility was assessed using the MTT test. A biomimetic model of the outer leaflet of a Leishmania plasma membrane was used to decipher the HePC-lipid interactions. RESULTS CH-OX, which is known to act more specifically on condensed membranes, therefore at the level of lipid rafts, gave a better extraction yield in HePC-resistant parasites, confirming the more rigid structure of their membranes than those of wild-type parasites. Sterol depletion was responsible for a 40% decrease in HePC susceptibility in both wild-type and HePC-resistant parasites. Sterol repletion of the sterol-depleted parasites restored HePC susceptibility. The biomimetic model of the outer leaflet of a Leishmania plasma membrane confirmed that condensed microdomains were able to incorporate higher quantities of HePC than fluid ones and this result was amplified when the sterol concentration was increased. CONCLUSIONS Sterol and lipid rafts probably play a significant role as an HePC reservoir providing a constant supply to the previously described transporter. In addition, (1)H NMR experiments suggested that HePC stimulated lipid trafficking in parasites.
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Affiliation(s)
- M Saint-Pierre-Chazalet
- Université Paris-Sud, UMR 8076, Chimiothérapie Antiparasitaire, Faculté de Pharmacie, 5 rue Jean-Baptiste Clément, Chatenay-Malabry, France
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84
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Singh N, Gupta R, Jaiswal AK, Sundar S, Dube A. Transgenic Leishmania donovani clinical isolates expressing green fluorescent protein constitutively for rapid and reliable ex vivo drug screening. J Antimicrob Chemother 2009; 64:370-4. [PMID: 19525291 DOI: 10.1093/jac/dkp206] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES Several Leishmania strains with episomal expression of green fluorescent protein (GFP) require constant drug pressure for its continuous expression and hence limit its use in ex vivo or in vivo systems. The aim of this study was to alleviate this problem by stably integrating the GFP gene into the parasite genome, so as to use these transfectants for ex vivo and in vivo drug screening. METHODS The GFP gene was integrated downstream of the 18S ribosomal promoter region of Leishmania donovani. After initial selection, GFP-expressing parasites-both sodium stibogluconate (SAG)-susceptible (2001) and -resistant (2039) isolates-were grown without adding G418. The infectivity of these transfectants to macrophages (J774.1) as well as to hamsters was checked. The ex vivo screening assay was standardized using standard antileishmanial drugs. RESULTS A constitutive and enhanced expression of GFP in promastigote and amastigote stages was achieved for approximately 12 months without any need for drug pressure. These transfectants were highly infective to macrophage cell lines as well as to hamsters, as observed by fluorescence microscopy and flow cytometry (FACS). GFP-tagged promastigotes as well as intracellular amastigotes were found to be highly susceptible to miltefosine, amphotericin B and pentamidine, in a concentration-dependent manner. SAG was inactive against the GFP-promastigotes, as well as SAG-resistant intracellular amastigotes, correlating well with earlier reports. CONCLUSIONS The GFP-transfectants were found to be suitable for FACS-based ex vivo screening assays. They were also infective to hamsters up to day 60 post-infection.
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Affiliation(s)
- Nasib Singh
- Division of Parasitology, Central Drug Research Institute, Lucknow, India
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85
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Thornton SJ, Wasan KM. The reformulation of amphotericin B for oral administration to treat systemic fungal infections and visceral leishmaniasis. Expert Opin Drug Deliv 2009; 6:271-84. [PMID: 19327044 DOI: 10.1517/17425240902802861] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Amphotericin B (AmB) is a parenterally administered broad-spectrum antifungal and leishmanicidal drug that has been on the market for over sixty years. Unfortunately, significant infusion-related side effects and renal toxicity often accompany treatment, limiting its clinical applications. Lipid-based formulations have somewhat ameliorated the associated toxicity, but the increased cost of formulations restricts widespread use. AmB is amphipathic and exhibits low solubility and permeability, resulting in negligible absorption when administered orally. Advances in drug delivery systems have overcome some of the solubility issues that prevent oral bioavailability and new formulations are currently in development. The existence of an effective, safe and inexpensive oral formulation of amphotericin B would have significant applications for the treatment of disseminated fungal infections and would dramatically expand access to treatment of visceral leishmaniasis by introducing a readily available highly tolerated oral formulation of a drug with known efficacy.
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Affiliation(s)
- Sheila J Thornton
- Division of Pharmaceutics and Biopharmaceutics, The University of British Columbia, 2146 East Mall, Vancouver, BC, V6T 1Z3, Canada
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86
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Riekhof WR, Voelker DR. The yeast plasma membrane P4-ATPases are major transporters for lysophospholipids. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:620-7. [PMID: 19268715 DOI: 10.1016/j.bbalip.2009.02.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Revised: 02/23/2009] [Accepted: 02/24/2009] [Indexed: 11/25/2022]
Abstract
The transbilayer movement of phospholipids plays an essential role in establishing and maintaining the asymmetric distribution of lipids in biological membranes. The P4-ATPase family has been implicated as the major transporters of the aminoglycerophospholipids in both surface and endomembrane systems. Historically, fluorescent lipid analogs have been used to monitor the lipid transport activity of the P4-ATPases. Recent evidence now demonstrates that lyso-phosphatidylethanolamine (lyso-PtdEtn) and lyso-phosphatidylcholine (lyso-PtdCho) are bona fide biological substrates transported by the yeast plasma membrane ATPases, Dnf1p and Dnf2p, in consort with a second protein Lem3p. Subsequent to transport, the lysophospholipids are acylated by the enzyme Ale1p to produce PtdEtn and PtdCho. The transport of the lysophospholipids occurs at rates sufficient to support all the PtdEtn and PtdCho synthesis required for rapid cell growth. The lysophospholipid transporters also utilize the anti-neoplastic and anti-parasitic ether lipid substrates related to edelfosine. The identification of biological substrates for the plasma membrane ATPases coupled with the power of yeast genetics now provides new tools to dissect the structure and function of the aminoglycerophospholipid transporters.
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Affiliation(s)
- Wayne R Riekhof
- Department of Medicine, National Jewish Health, 1400 Jackson St., Denver, CO 80206, USA
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87
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Ryczak J, Kunick C. [Agents for the treatment of leishmaniasis. Antimony, and more]. PHARMAZIE IN UNSERER ZEIT 2009; 38:538-544. [PMID: 19862714 DOI: 10.1002/pauz.200900342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Affiliation(s)
- Jasmin Ryczak
- Institut für Pharmazeutische Chemie Technische Universität Carolo-Wilhelmina zu Braunschweig, Beethovenstrasse 55, 38106 Braunschweig
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Abstract
BACKGROUND Miltefosine is the first recognized oral treatment for leishmaniasis. It was first registered, in 2002, for Indian visceral leishmaniasis, and was reviewed by the present author in 2005. QUESTION Miltefosine is now being used for the full range of clinical leishmaniasis. The present review addresses non-clinical and clinical advances since 2005. METHODS PubMed was accessed for all articles on miltefosine from 2005 to 2008. RESULTS/CONCLUSIONS Miltefosine is effective and can be recommended for visceral disease in India and in Ethiopia, and for cutaneous disease in Colombia and Bolivia. For unusual forms of disease that require long periods of treatment such as diffuse cutaneous leishmaniasis and post-kala-azar dermal leishmaniasis, oral miltefosine is probably the treatment of choice.
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89
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Choudhury K, Zander D, Kube M, Reinhardt R, Clos J. Identification of a Leishmania infantum gene mediating resistance to ‘ and SbIII. Int J Parasitol 2008; 38:1411-23. [DOI: 10.1016/j.ijpara.2008.03.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Revised: 03/16/2008] [Accepted: 03/17/2008] [Indexed: 11/26/2022]
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90
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Sitamaquine sensitivity in Leishmania species is not mediated by drug accumulation in acidocalcisomes. Antimicrob Agents Chemother 2008; 52:4030-6. [PMID: 18794384 DOI: 10.1128/aac.00964-08] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sitamaquine (WR6026), an 8-aminoquinoline derivative, is a new antileishmanial oral drug. As a lipophilic weak base, it rapidly accumulates in acidic compartments, represented mainly by acidocalcisomes. In this work, we show that the antileishmanial action of sitamaquine is unrelated to its level of accumulation in these acidic vesicles. We have observed significant differences in sitamaquine sensitivity and accumulation between Leishmania species and strains, and interestingly, there is no correlation between them. However, there is a relationship between the levels of accumulation of sitamaquine and acidotropic probes, acidocalcisomes size, and polyphosphate levels. The Leishmania major AP3delta-null mutant line, in which acidocalcisomes are devoid of their usual polyphosphate and proton content, is unable to accumulate sitamaquine; however, both the parental strain and the AP3delta-null mutants showed similar sensitivities to sitamaquine. Our findings provide clear evidence that the antileishmanial action of sitamaquine is unrelated to its accumulation in acidocalcisomes.
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91
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The relationship between leishmaniasis and AIDS: the second 10 years. Clin Microbiol Rev 2008; 21:334-59, table of contents. [PMID: 18400800 DOI: 10.1128/cmr.00061-07] [Citation(s) in RCA: 574] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
To date, most Leishmania and human immunodeficiency virus (HIV) coinfection cases reported to WHO come from Southern Europe. Up to the year 2001, nearly 2,000 cases of coinfection were identified, of which 90% were from Spain, Italy, France, and Portugal. However, these figures are misleading because they do not account for the large proportion of cases in many African and Asian countries that are missed due to a lack of diagnostic facilities and poor reporting systems. Most cases of coinfection in the Americas are reported in Brazil, where the incidence of leishmaniasis has spread in recent years due to overlap with major areas of HIV transmission. In some areas of Africa, the number of coinfection cases has increased dramatically due to social phenomena such as mass migration and wars. In northwest Ethiopia, up to 30% of all visceral leishmaniasis patients are also infected with HIV. In Asia, coinfections are increasingly being reported in India, which also has the highest global burden of leishmaniasis and a high rate of resistance to antimonial drugs. Based on the previous experience of 20 years of coinfection in Europe, this review focuses on the management of Leishmania-HIV-coinfected patients in low-income countries where leishmaniasis is endemic.
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92
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Pharmacokinetics of miltefosine in Old World cutaneous leishmaniasis patients. Antimicrob Agents Chemother 2008; 52:2855-60. [PMID: 18519729 DOI: 10.1128/aac.00014-08] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
The pharmacokinetics of miltefosine in leishmaniasis patients are, to a great extent, unknown. We examined and characterized the pharmacokinetics of miltefosine in a group of patients with Old World (Leishmania major) cutaneous leishmaniasis. Miltefosine plasma concentrations were determined in samples taken during and up to 5 months after the end of treatment from 31 Dutch military personnel who contracted cutaneous leishmaniasis in Afghanistan and were treated with 150 mg miltefosine/day for 28 days. Samples were analyzed with a validated liquid chromatography-tandem mass spectrometry assay with a lower limit of quantification (LLOQ) of 4 ng/ml. Population pharmacokinetic modeling was performed with nonlinear mixed-effect modeling, using NONMEM. The pharmacokinetics of miltefosine could best be described by an open two-compartment disposition model, with a first elimination half-life of 7.05 days and a terminal elimination half-life of 30.9 days. The median concentration in the last week of treatment (days 22 to 28) was 30,800 ng/ml. The maximum duration of follow-up was 202 days after the start of treatment. All analyzed samples contained a concentration above the LLOQ. Miltefosine is eliminated from the body much slower than previously thought and is therefore still detectable in human plasma samples taken 5 to 6 months after the end of treatment. The presence of subtherapeutic miltefosine concentrations in the blood beyond 5 months after treatment might contribute to the selection of resistant parasites, and moreover, the measures for preventing the teratogenic risks of miltefosine treatment should be reconsidered.
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93
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Chollet C, Crousse B, Bories C, Bonnet-Delpon D, Loiseau PM. In vitro antileishmanial activity of fluoro-artemisinin derivatives against Leishmania donovani. Biomed Pharmacother 2008; 62:462-5. [PMID: 18538529 DOI: 10.1016/j.biopha.2008.04.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Accepted: 04/10/2008] [Indexed: 11/16/2022] Open
Abstract
The antileishmanial activity of 19 fluoro-artemisinin derivatives was evaluated in vitro against the promastigote forms of Leishmania donovani. The most active compound BB 201, an amino derivative, exhibited an IC50 at about 1microM and no cross-resistance was found on miltefosine-resistant and sitamaquine-resistant lines. Despite these promising data, no activity was observed on intramacrophage amastigote stage. Although the membranes that have to be crossed by the compounds and pH conditions between intraerythrocyte Plasmodium and intramacrophage Leishmania have similarities, the targets affected by artemisinin derivatives in promastigotes could be differentially expressed in amastigotes.
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Affiliation(s)
- Constance Chollet
- Molécules Fluorées et Chimie Médicinale, UMR 8076 CNRS, IFR 141, Faculté de Pharmacie, Univ Paris-Sud, Rue Jean-Baptiste Clément, F-92290 Châtenay-Malabry, France
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94
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Bories C, Cojean S, Huteau F, Loiseau PM. Selection and phenotype characterisation of sitamaquine-resistant promastigotes of Leishmania donovani. Biomed Pharmacother 2008; 62:164-7. [PMID: 18249083 DOI: 10.1016/j.biopha.2007.12.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2007] [Accepted: 12/12/2007] [Indexed: 11/26/2022] Open
Abstract
A Leishmania donovani promastigote line resistant to 160microM sitamaquine, named SITA-160R, was selected in vitro by continuous stepwise drug pressure. SITA-160R line was able to infect murine peritoneal macrophages in vitro in the same manner as the wild-type line (WT) but was less infective for Balb/c mice than its parent WT clone. This line was about five and three times more resistant to sitamaquine than the WT line on promastigote and intramacrophage amastigote forms, respectively. No cross-resistance with other antileishmanial agents was observed and this resistance was stable when parasites were subcultured in drug-free medium for a long time or after in vivo passage.
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Affiliation(s)
- Christian Bories
- Groupe Chimiothérapie Antiparasitaire, UMR 8076 CNRS, Faculté de Pharmacie, Univ Paris-Sud 11, 92290-Châtenay-Malabry, France
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95
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BoseDasgupta S, Ganguly A, Roy A, Mukherjee T, Majumder HK. A novel ATP-binding cassette transporter, ABCG6 is involved in chemoresistance of Leishmania. Mol Biochem Parasitol 2007; 158:176-88. [PMID: 18243364 DOI: 10.1016/j.molbiopara.2007.12.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2007] [Revised: 12/10/2007] [Accepted: 12/13/2007] [Indexed: 10/22/2022]
Abstract
ATP-binding cassette (ABC) transporters constitute the biggest family of membrane proteins involved in drug resistance and other biological activities. Resistance of leishmanial parasites to therapeutic drugs continues to escalate in developing countries and in many instances it is due to overexpressed ABC efflux pumps. Progressively adapted camptothecin (CPT)-resistant parasites show overexpression of a novel ABC transporter, which was classified as ABCG6. Transfection and overexpression of LdABCG6 in wild type parasites, shows its localization primarily in the plasma membrane and flagellar pocket region. Overexpressed LdABCG6 confers substantial CPT resistance to the parasites by rapid drug efflux. Various inhibitors have been tested for their ability to revert the CPT-resistant phenotype to specifically understand the inhibition of LdABCG6 transporter. Transport experiments using everted membrane vesicles were carried out to gain an insight into the kinetics of drug transport. This study provides further knowledge of specific membrane traffic ATPase and its involvement in the chemoresistance of Leishmania.
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Affiliation(s)
- Somdeb BoseDasgupta
- Department of Molecular Parasitology, Infectious Disease Group, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Kolkata 700032, India
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96
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Saugar JM, Delgado J, Hornillos V, Luque-Ortega JR, Amat-Guerri F, Acuña AU, Rivas L. Synthesis and Biological Evaluation of Fluorescent Leishmanicidal Analogues of Hexadecylphosphocholine (Miltefosine) as Probes of Antiparasite Mechanisms. J Med Chem 2007; 50:5994-6003. [DOI: 10.1021/jm070595+] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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97
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Ameen M. Cutaneous leishmaniasis: therapeutic strategies and future directions. Expert Opin Pharmacother 2007; 8:2689-99. [DOI: 10.1517/14656566.8.16.2689] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Mahreen Ameen
- Consultant Dermatologist, Royal Free Hospital, Department of Dermatology, London NW3 2QG, UK ;
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98
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Seifert K, Lemke A, Croft SL, Kayser O. Antileishmanial structure-activity relationships of synthetic phospholipids: in vitro and in vivo activities of selected derivatives. Antimicrob Agents Chemother 2007; 51:4525-8. [PMID: 17908944 PMCID: PMC2167978 DOI: 10.1128/aac.00465-07] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Antileishmanial activities of 91 synthetic phospholipids against Leishmania donovani were evaluated in vitro and cytotoxicity assessed against two mammalian cell lines. Promising compounds were tested further in vivo. In vitro structure-activity relationships showed a positive contribution of head groups bearing ring systems (N-methylpiperidino and N-methylmorpholino) to antileishmanial activity.
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Affiliation(s)
- Karin Seifert
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.
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99
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Seifert K, Pérez-Victoria FJ, Stettler M, Sánchez-Cañete MP, Castanys S, Gamarro F, Croft SL. Inactivation of the miltefosine transporter, LdMT, causes miltefosine resistance that is conferred to the amastigote stage of Leishmania donovani and persists in vivo. Int J Antimicrob Agents 2007; 30:229-35. [PMID: 17628445 DOI: 10.1016/j.ijantimicag.2007.05.007] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 04/30/2007] [Accepted: 05/01/2007] [Indexed: 11/21/2022]
Abstract
Miltefosine (hexadecylphosphocholine) is the first oral antileishmanial drug. In this study, we addressed the question whether miltefosine-resistant Leishmania donovani promastigotes transform to miltefosine-resistant amastigotes. A promastigote line, M-mutR, showed defective internalisation of miltefosine owing to mutations in LdMT, similar to previously described resistant lines. M-mutR parasites were infective to macrophages in vitro as well as in BALB/c mice in vivo. There was good correlation of in vitro resistance indices between promastigotes and intracellular amastigotes. Most importantly, M-mutR parasites retained the resistant phenotype in vivo, with no decrease of hepatic burden in BALB/c mice following miltefosine treatment up to 30 mg/kg (ca. 90% inhibition in wild-type infections). No cross-resistance to other antileishmanial drugs was observed in M-mutR amastigotes.
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Affiliation(s)
- Karin Seifert
- Department of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
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Soares DC, Pereira CG, Meireles MAA, Saraiva EM. Leishmanicidal activity of a supercritical fluid fraction obtained from Tabernaemontana catharinensis. Parasitol Int 2007; 56:135-9. [PMID: 17306614 DOI: 10.1016/j.parint.2007.01.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2006] [Revised: 01/11/2007] [Accepted: 01/15/2007] [Indexed: 10/23/2022]
Abstract
The branches and leaves of Tabernaemontana catharinensis were extracted with supercritical fluid using a mixture of CO(2) plus ethanol (SFE), and the indole alkaloid enriched fraction (AF3) was selected for anti-Leishmania activity studies. We found that AF3 exhibits a potent effect against intracellular amastigotes of Leishmania amazonensis, a causative agent of New World cutaneous leishmaniasis. AF3 inhibits Leishmania survival in a dose-dependent manner, and reached 88% inhibition of amastigote growth at 100 microg/mL. The anti-parasite effect was independent of nitric oxide (NO), since AF3 was able to inhibit NO production induced by IFN-gamma plus LPS. In addition, AF3 inhibited TGF-beta production, which could have facilitated AF3-mediated parasite killing. The AF3 fraction obtained from SFE was nontoxic for host macrophages, as assessed by plasma membrane integrity and mitochondrial activity. We conclude that SFE is an efficient method for obtaining bioactive indole alkaloids from plant extracts. Importantly, this method preserved the alkaloid properties associated with inhibition of Leishmania growth in macrophages without toxicity to host cells.
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Affiliation(s)
- Deivid Costa Soares
- Departamento de Imunologia, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, 21941-590, Brazil
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