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Makhmudiyarova NN, Ishmukhametova IR. Urea and Thiourea Derivatives in the Synthesis of Hexaoxaazadispiroalkanecarboxamides. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2022. [DOI: 10.1134/s1070428022120260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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2
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A simple quinoline salt derivative is active in vitro against plasmodium Faciparum asexual blood stages and inhibits the development of cerebral malaria in murine model. Chem Biol Interact 2022; 355:109848. [PMID: 35149084 DOI: 10.1016/j.cbi.2022.109848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 01/28/2022] [Accepted: 02/07/2022] [Indexed: 11/22/2022]
Abstract
Chloroquine (CQ) was the most effective and widely used drug for the prophylaxis and treatment of severe and non-severe malaria. Although its prophylactic use has led to resistance to P. falciparum in all endemic countries, CQ still remains the drug of choice for the treatment of vivax malaria. Otherwise, the speed in which parasite resistance to available antimalarials rises and spreads in endemic regions points to the urgent need for the development of new antimalarials. Quinoline derivatives have been used as a tool in the search for new drugs and were investigated in the present study in an attempt to produce a HIT compound to avoid the cerebral malarial (CM). Seven compounds were synthesized, including three quinoline derivate salts. The cytotoxicity and antiplasmodial activity were assayed in vitro, highlighting compound 3 as a HIT, which also showed interaction with ferriprotoporphyrin IX similarly to CQ. Physicochemical and pharmacokinetic properties of absorption were found to be favorable when analyzed in silico. The in vivo assays, using the experimental cerebral malaria (ECM) model, showed important values of parasite growth inhibition on the 7th day-post infection (Q15 15 mg/kg: 76.9%, Q30 30 mg/kg: 90,1% and Q50 50 mg/kg: 92,9%). Compound 3 also showed significant protection against the development of CM, besides hepatic and renal parameters better than CQ. In conclusion, this quinoline derivative demonstrated promising activity for the treatment of malaria and was able to avoid the development of severe malaria in mice.
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3
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Karnatak M, Hassam M, Singh AS, Yadav DK, Singh C, Puri SK, Verma VP. Novel hydrazone derivatives of N-amino-11-azaartemisinin with high order of antimalarial activity against multidrug-resistant Plasmodium yoelii nigeriensis in Swiss mice via intramuscular route. Bioorg Med Chem Lett 2021; 58:128522. [PMID: 34974111 DOI: 10.1016/j.bmcl.2021.128522] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/23/2021] [Accepted: 12/26/2021] [Indexed: 01/27/2023]
Abstract
Novel hydrazone derivatives 10a-m were prepared from N-Amino-11-azaartemisinin (9) and screened for their antimalarial activity by oral and intramuscular (i.m.) routes against multidrug-resistant Plasmodium yoelii in Swiss mice model. Several of the hydrazone derivatives showed higher order of antimalarial activity. Compounds 10b, 10g, 10m provided 100% protection to the infected mice at the dose of 24 mg/kg × 4 days via oral route. Fluorenone based hydrazone 10m the most active compound of the series, provided 100% protection at the dose of 6 mg/kg × 4 days via intramuscular route and also provided 100% protection at the dose of 12 mg/kg × 4 days via oral route. While artemisinin gave 100% protection at 48 mg/kg × 4 days and only 60% protection at 24 mg/kg × 4 days via intramuscular (i.m.) route. Compound 10m found to be four-fold more active than artemisinin via intramuscular route.
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Affiliation(s)
- Manvika Karnatak
- Department of Chemistry, Banasthali University, Banasthali Newai 304022 Rajasthan, India
| | - Mohammad Hassam
- Medicinal & Process Chemistry Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, India
| | - Ajit Shankar Singh
- Medicinal & Process Chemistry Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, India
| | - Dinesh Kumar Yadav
- Department of Chemistry, Mohanlal Sukhadia University, Udaipur 313001, India
| | - Chandan Singh
- Medicinal & Process Chemistry Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, India
| | - Sunil K Puri
- Parasitology Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, India
| | - Ved Prakash Verma
- Medicinal & Process Chemistry Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, India; Department of Chemistry, Banasthali University, Banasthali Newai 304022 Rajasthan, India.
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4
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Marinho JA, Martins Guimarães DS, Glanzmann N, de Almeida Pimentel G, Karine da Costa Nunes I, Gualberto Pereira HM, Navarro M, de Pilla Varotti F, David da Silva A, Abramo C. In vitro and in vivo antiplasmodial activity of novel quinoline derivative compounds by molecular hybridization. Eur J Med Chem 2021; 215:113271. [PMID: 33596489 DOI: 10.1016/j.ejmech.2021.113271] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 01/31/2021] [Accepted: 02/01/2021] [Indexed: 01/01/2023]
Abstract
Chloroquine (CQ) has been the main treatment for malaria in regions where there are no resistant strains. Molecular hybridization techniques have been used as a tool in the search for new drugs and was implemented in the present study in an attempt to produce compound candidates to treat malarial infections by CQ-resistant strains. Two groups of molecules were produced from the 4-aminoquinoline ring in conjugation to hydrazones (HQ) and imines (IQ). Physicochemical and pharmacokinetic properties were found to be favorable when analyzed in silico and cytotoxicity and antiplasmodial activity were assayed in vitro and in vivo showing low cytotoxicity and selectiveness to the parasites. Candidates IQ5 and IQ6 showed important values of parasite growth inhibition in vivo on the 5th day after infection (IQ5 15 mg/kg = 72.64% and IQ6 15 mg/kg = 71.15% and 25 mg/kg = 93.7%). IQ6 also showed interaction with ferriprotoporphyrin IX similarly to CQ. The process of applying condensation reactions to yield imines is promising and capable of producing molecules with antiplasmodial activity.
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Affiliation(s)
- Juliane Aparecida Marinho
- Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Campus Universitário, Juiz de Fora, Minas Gerais, CEP: 36036-900, Brazil.
| | - Daniel Silqueira Martins Guimarães
- Núcleo de Pesquisa Em Química Biológica, Universidade Federal de São João Del Rei - Campus Centro Oeste, 400 Sebastião Gonçalves Coelho Street, Divinópolis, MG, 35501-296, Brazil.
| | - Nícolas Glanzmann
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Juiz de Fora, Campus Universitário, Juiz de Fora, Minas Gerais, CEP: 36036-900, Brazil.
| | - Giovana de Almeida Pimentel
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Juiz de Fora, Campus Universitário, Juiz de Fora, Minas Gerais, CEP: 36036-900, Brazil.
| | - Izabelle Karine da Costa Nunes
- Laboratório de Apoio Ao Desenvolvimento Tecnológico, LADETEC/IQ, Universidade Federal Do Rio de Janeiro, Av. Horácio Macedo, 1281 - Polo de Química, Cidade Universitária, Ilha Do Fundão, RJ, 21941-598, Brazil.
| | - Henrique Marcelo Gualberto Pereira
- Laboratório de Apoio Ao Desenvolvimento Tecnológico, LADETEC/IQ, Universidade Federal Do Rio de Janeiro, Av. Horácio Macedo, 1281 - Polo de Química, Cidade Universitária, Ilha Do Fundão, RJ, 21941-598, Brazil.
| | - Maribel Navarro
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Juiz de Fora, Campus Universitário, Juiz de Fora, Minas Gerais, CEP: 36036-900, Brazil.
| | - Fernando de Pilla Varotti
- Núcleo de Pesquisa Em Química Biológica, Universidade Federal de São João Del Rei - Campus Centro Oeste, 400 Sebastião Gonçalves Coelho Street, Divinópolis, MG, 35501-296, Brazil.
| | - Adilson David da Silva
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Juiz de Fora, Campus Universitário, Juiz de Fora, Minas Gerais, CEP: 36036-900, Brazil.
| | - Clarice Abramo
- Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Campus Universitário, Juiz de Fora, Minas Gerais, CEP: 36036-900, Brazil.
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Driving antimalarial design through understanding of target mechanism. Biochem Soc Trans 2020; 48:2067-2078. [PMID: 32869828 PMCID: PMC7609028 DOI: 10.1042/bst20200224] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 07/23/2020] [Accepted: 07/27/2020] [Indexed: 11/17/2022]
Abstract
Malaria continues to be a global health threat, affecting approximately 219 million people in 2018 alone. The recurrent development of resistance to existing antimalarials means that the design of new drug candidates must be carefully considered. Understanding of drug target mechanism can dramatically accelerate early-stage target-based development of novel antimalarials and allows for structural modifications even during late-stage preclinical development. Here, we have provided an overview of three promising antimalarial molecular targets, PfDHFR, PfDHODH and PfA-M1, and their associated inhibitors which demonstrate how mechanism can inform drug design and be effectively utilised to generate compounds with potent inhibitory activity.
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Makhmudiyarova NN, Ishmukhametova IR, Dzhemileva LU, D’yakonov VA, Ibragimov AG, Dzhemilev UM. Hydrazines in the Synthesis of Cytotoxic N-Aryl(alkyl)-N-(hexaoxazadispiroalkyl)amines. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2020. [DOI: 10.1134/s1070428020050115] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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7
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Cui H, Chen X, Bai M, Han D, Lin L, Dong M. Multipathway Antibacterial Mechanism of a Nanoparticle-Supported Artemisinin Promoted by Nitrogen Plasma Treatment. ACS APPLIED MATERIALS & INTERFACES 2019; 11:47299-47310. [PMID: 31797661 DOI: 10.1021/acsami.9b15124] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Artemisinin has excellent antimalarial, antiparasitic, and antibacterial activities; however, the poor water solubility of artemisinin crystal limits their application in antibiosis. Herein, artemisinin crystal was first composited with silica nanoparticles (SNPs) to form an artemisinin@silica nanoparticle (A@SNP). After treating with nitrogen plasma, the aqueous solubility of plasma-treated A@SNP (A@SNP-p) approaches 42.26%, which is possibly attributed to the exposure of hydrophilic groups such as -OH groups on the SNPs during the plasma process. Compared with the pristine A@SNP, the antibacterial activity of A@SNP-p against both Gram-positive and Gram-negative strains is further enhanced, and its bactericidal rate against both strains exceeded 6 log CFU/mL (>99.9999%), which is contributed by the increased water solubility of the A@SNP-p. A possible multipathway antibacterial mechanism of A@SNP was proposed and preliminarily proved by the changes of intracellular materials of bacteria and the inhibition of bacterial metabolism processes, including the HMP pathway in Gram-negative strain and EMP pathway in Gram-positive strain, after treating with A@SNP-p. These findings from the present work will provide a new view for fabricating artemisinin-based materials as antibiotics.
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Affiliation(s)
- Haiying Cui
- School of Food & Biological Engineering , Jiangsu University , Zhenjiang 212013 , China
| | - Xiaochen Chen
- Interdisciplinary Nanoscience Center, Sino-Danish Center for Education and Research , Aarhus University , Aarhus 8000 , Denmark
| | - Mei Bai
- School of Food & Biological Engineering , Jiangsu University , Zhenjiang 212013 , China
| | - Dong Han
- National Center for Nanoscience and Technology , Beijing , China 100190
| | - Lin Lin
- School of Food & Biological Engineering , Jiangsu University , Zhenjiang 212013 , China
| | - Mingdong Dong
- Interdisciplinary Nanoscience Center, Sino-Danish Center for Education and Research , Aarhus University , Aarhus 8000 , Denmark
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8
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Tirrell AR, Vendrely KM, Checkley LA, Davis SZ, McDew-White M, Cheeseman IH, Vaughan AM, Nosten FH, Anderson TJC, Ferdig MT. Pairwise growth competitions identify relative fitness relationships among artemisinin resistant Plasmodium falciparum field isolates. Malar J 2019; 18:295. [PMID: 31462253 PMCID: PMC6714446 DOI: 10.1186/s12936-019-2934-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 08/23/2019] [Indexed: 02/08/2023] Open
Abstract
Background Competitive outcomes between co-infecting malaria parasite lines can reveal fitness disparities in blood stage growth. Blood stage fitness costs often accompany the evolution of drug resistance, with the expectation that relatively fitter parasites will be more likely to spread in populations. With the recent emergence of artemisinin resistance, it is important to understand the relative competitive fitness of the metabolically active asexual blood stage parasites. Genetically distinct drug resistant parasite clones with independently evolved sets of mutations are likely to vary in asexual proliferation rate, contributing to their chance of transmission to the mosquito vector. Methods An optimized in vitro 96-well plate-based protocol was used to quantitatively measure-head-to-head competitive fitness during blood stage development between seven genetically distinct field isolates from a hotspot of emerging artemisinin resistance and the laboratory strain, NF54. These field isolates were isolated from patients in Southeast Asia carrying different alleles of kelch13 and included both artemisinin-sensitive and artemisinin-resistant isolates. Fluorescent labeled microsatellite markers were used to track the relative densities of each parasite throughout the co-growth period of 14–60 days. All-on-all competitions were conducted for the panel of eight parasite lines (28 pairwise competitions) to determine their quantitative competitive fitness relationships. Results Twenty-eight pairwise competitive growth outcomes allowed for an unambiguous ranking among a set of seven genetically distinct parasite lines isolated from patients in Southeast Asia displaying a range of both kelch13 alleles and clinical clearance times and a laboratory strain, NF54. This comprehensive series of assays established the growth relationships among the eight parasite lines. Interestingly, a clinically artemisinin resistant parasite line that carries the wild-type form of kelch13 outcompeted all other parasites in this study. Furthermore, a kelch13 mutant line (E252Q) was competitively more fit without drug than lines with other resistance-associated kelch13 alleles, including the C580Y allele that has expanded to high frequencies under drug pressure in Southeast Asian resistant populations. Conclusions This optimized competitive growth assay can be employed for assessment of relative growth as an index of fitness during the asexual blood stage growth between natural lines carrying different genetic variants associated with artemisinin resistance. Improved understanding of the fitness costs of different parasites proliferating in human blood and the role different resistance mutations play in the context of specific genetic backgrounds will contribute to an understanding of the potential for specific mutations to spread in populations, with the potential to inform targeted strategies for malaria therapy.
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Affiliation(s)
- Abigail R Tirrell
- Eck Institute for Global Health, Dept. of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Katelyn M Vendrely
- Eck Institute for Global Health, Dept. of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Lisa A Checkley
- Eck Institute for Global Health, Dept. of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Sage Z Davis
- Eck Institute for Global Health, Dept. of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | | | | | | | - François H Nosten
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Mae Sot, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine Research Building, University of Oxford Old Road Campus, Oxford, UK
| | | | - Michael T Ferdig
- Eck Institute for Global Health, Dept. of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA.
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9
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Modugu NR, Mehta G. Synthesis of the Polyoxygenated Cyclohexanoid Core of Bioactive Glycosides Xylosmin and Flacourtosides E and F. J Org Chem 2018; 83:10573-10579. [DOI: 10.1021/acs.joc.8b01389] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nagi Reddy Modugu
- Department of Organic Synthesis and Process Chemistry (CSIR), Indian Institute of Chemical Technology, Hyderabad 500007, India
| | - Goverdhan Mehta
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India
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10
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Boyce MR, Menya D, Turner EL, Laktabai J, Prudhomme-O'Meara W. Evaluation of malaria rapid diagnostic test (RDT) use by community health workers: a longitudinal study in western Kenya. Malar J 2018; 17:206. [PMID: 29776359 PMCID: PMC5960182 DOI: 10.1186/s12936-018-2358-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 05/15/2018] [Indexed: 12/26/2022] Open
Abstract
Background Malaria rapid diagnostic tests (RDTs) are a simple, point-of-care technology that can improve the diagnosis and subsequent treatment of malaria. They are an increasingly common diagnostic tool, but concerns remain about their use by community health workers (CHWs). These concerns regard the long-term trends relating to infection prevention measures, the interpretation of test results and adherence to treatment protocols. This study assessed whether CHWs maintained their competency at conducting RDTs over a 12-month timeframe, and if this competency varied with specific CHW characteristics. Methods From June to September, 2015, CHWs (n = 271) were trained to conduct RDTs using a 3-day validated curriculum and a baseline assessment was completed. Between June and August, 2016, CHWs (n = 105) were randomly selected and recruited for follow-up assessments using a 20-step checklist that classified steps as relating to safety, accuracy, and treatment; 103 CHWs participated in follow-up assessments. Poisson regressions were used to test for associations between error count data at follow-up and Poisson regression models fit using generalized estimating equations were used to compare data across time-points. Results At both baseline and follow-up observations, at least 80% of CHWs correctly completed 17 of the 20 steps. CHWs being 50 years of age or older was associated with increased total errors and safety errors at baseline and follow-up. At follow-up, prior experience conducting RDTs was associated with fewer errors. Performance, as it related to the correct completion of all checklist steps and safety steps, did not decline over the 12 months and performance of accuracy steps improved (mean error ratio: 0.51; 95% CI 0.40–0.63). Visual interpretation of RDT results yielded a CHW sensitivity of 92.0% and a specificity of 97.3% when compared to interpretation by the research team. None of the characteristics investigated was found to be significantly associated with RDT interpretation. Conclusions With training, most CHWs performing RDTs maintain diagnostic testing competency over at least 12 months. CHWs generally perform RDTs safely and accurately interpret results. Younger age and prior experiences with RDTs were associated with better testing performance. Future research should investigate the mode by which CHW characteristics impact RDT procedures. Electronic supplementary material The online version of this article (10.1186/s12936-018-2358-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Matthew R Boyce
- Duke Global Health Institute, Duke University, Durham, NC, USA.
| | - Diana Menya
- Department of Epidemiology and Biostatistics, Moi University School of Public Health, College of Health Sciences, Eldoret, Kenya
| | - Elizabeth L Turner
- Duke Global Health Institute, Duke University, Durham, NC, USA.,Department of Biostatistics and Bioinformatics, Duke University, Durham, NC, USA
| | - Jeremiah Laktabai
- Department of Family Medicine, Moi University School of Medicine, Eldoret, Kenya
| | - Wendy Prudhomme-O'Meara
- Duke Global Health Institute, Duke University, Durham, NC, USA.,Department of Epidemiology and Biostatistics, Moi University School of Public Health, College of Health Sciences, Eldoret, Kenya.,Duke University Medical Center, Durham, NC, USA
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Novel Immunoinformatics Approaches to Design Multi-epitope Subunit Vaccine for Malaria by Investigating Anopheles Salivary Protein. Sci Rep 2018; 8:1125. [PMID: 29348555 PMCID: PMC5773588 DOI: 10.1038/s41598-018-19456-1] [Citation(s) in RCA: 152] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 01/02/2018] [Indexed: 12/19/2022] Open
Abstract
Malaria fever has been pervasive for quite a while in tropical developing regions causing high morbidity and mortality. The causal organism is a protozoan parasite of genus Plasmodium which spreads to the human host by the bite of hitherto infected female Anopheles mosquito. In the course of biting, a salivary protein of Anopheles helps in blood feeding behavior and having the ability to elicit the host immune response. This study represents a series of immunoinformatics approaches to design multi-epitope subunit vaccine using Anopheles mosquito salivary proteins. Designed subunit vaccine was evaluated for its immunogenicity, allergenicity and physiochemical parameters. To enhance the stability of vaccine protein, disulfide engineering was performed in a region of high mobility. Codon adaptation and in silico cloning was also performed to ensure the higher expression of designed subunit vaccine in E. coli K12 expression system. Finally, molecular docking and simulation study was performed for the vaccine protein and TLR-4 receptor, to determine the binding free energy and complex stability. Moreover, the designed subunit vaccine was found to induce anti-salivary immunity which may have the ability to prevent the entry of Plasmodium sporozoites into the human host.
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12
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Patankar S, Sharma S, Rathod PK, Duraisingh MT. Malaria in India: The Need for New Targets for Diagnosis and Detection of Plasmodium vivax. Proteomics Clin Appl 2018; 12:e1700024. [PMID: 29193853 DOI: 10.1002/prca.201700024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 08/28/2017] [Indexed: 11/08/2022]
Abstract
Plasmodium vivax is a protozoan parasite that is one of the causative agents of human malaria. Due to several occult features of its life cycle, P. vivax threatens to be a problem for the recent efforts toward elimination of malaria globally. With an emphasis on malaria elimination goals, the authors summarize the major gaps in P. vivax diagnosis and describe how proteomics technologies have begun to contribute toward the discovery of antigens that could be used for various technology platforms and applications. The authors suggest areas where, in the future, proteomics technologies could fill in gaps in P. vivax diagnosis that have proved difficult. The discovery of new parasite antigens, host responses, and immune signatures using proteomics technologies will be a key part of the global malaria elimination efforts.
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Affiliation(s)
- Swati Patankar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India.,Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Shobhona Sharma
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | | | - Manoj T Duraisingh
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
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Zhang M, Gallego-Delgado J, Fernandez-Arias C, Waters NC, Rodriguez A, Tsuji M, Wek RC, Nussenzweig V, Sullivan WJ. Inhibiting the Plasmodium eIF2α Kinase PK4 Prevents Artemisinin-Induced Latency. Cell Host Microbe 2017; 22:766-776.e4. [DOI: 10.1016/j.chom.2017.11.005] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Revised: 09/26/2017] [Accepted: 11/10/2017] [Indexed: 01/09/2023]
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Varela JN, Lammoglia Cobo MF, Pawar SV, Yadav VG. Cheminformatic Analysis of Antimalarial Chemical Space Illuminates Therapeutic Mechanisms and Offers Strategies for Therapy Development. J Chem Inf Model 2017; 57:2119-2131. [PMID: 28810125 DOI: 10.1021/acs.jcim.7b00072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The clear and present danger of malaria, which has been amplified in recent years by climate change, and the progressive thinning of our drug arsenal over the past two decades raise uncomfortable questions about the current state and future of antimalarial drug development. Besides suffering from many of the same technical challenges that affect drug development in other disease areas, the quest for new antimalarial therapies is also hindered by the complex, dynamic life cycle of the malaria parasite, P. falciparum, in its mosquito and human hosts, and its role thereof in the elicitation of drug resistance. New strategies are needed in order to ensure economical and expeditious development of new, more efficacious treatments. In the present study, we employ open-source cheminformatics tools to analyze the chemical space traversed by approved antimalarial drugs and promising candidates at various stages of development to uncover insights that could shape future endeavors in the field. Our scaffold-centric analysis reveals that the antimalarial chemical space is disjointed and segregated into a few dominant structural groups. In fact, the structures of antimalarial drugs and drug candidates are distributed according to Pareto's principle. This structural convergence can potentially be exploited for future drug discovery by incorporating it into bioinformatics workflows that are typically employed for solving problems in structural biology. Significantly, we demonstrate how molecular scaffold hunting can be applied to unearth putative mechanisms of action of drugs whose activities remain a mystery, and how scaffold-centric analysis of drug space can also provide a recipe for combination therapies that minimize the likelihood of emergence of drug resistance, as well as identify areas on which to focus efforts. Finally, we also observe that over half of the molecules in the antimalarial space bear no resemblance to other molecules in the collection, which suggests that the pharmacobiology of antimalarial drugs has not been entirely surveyed.
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Affiliation(s)
- Julia Nogueira Varela
- Department of Chemical & Biological Engineering, The University of British Columbia , Vancouver, BC, Canada , V6T 1Z3
| | - María Fernanda Lammoglia Cobo
- Department of Chemical & Biological Engineering, The University of British Columbia , Vancouver, BC, Canada , V6T 1Z3.,Life Sciences Department, Monterrey Institute of Technology and Higher Education , Mexico City Campus, Mexico City, Mexico , 14380
| | - Sandip V Pawar
- Department of Chemical & Biological Engineering, The University of British Columbia , Vancouver, BC, Canada , V6T 1Z3
| | - Vikramaditya G Yadav
- Department of Chemical & Biological Engineering, The University of British Columbia , Vancouver, BC, Canada , V6T 1Z3.,Neglected Global Diseases Initiative, The University of British Columbia , Vancouver, BC, Canada , V6T 1Z3
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15
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Sweileh WM, Al-Jabi SW, Sawalha AF, AbuTaha AS, Zyoud SH. Bibliometric Analysis of Worldwide Publications on Antimalarial Drug Resistance (2006-2015). Malar Res Treat 2017; 2017:6429410. [PMID: 28856028 PMCID: PMC5569636 DOI: 10.1155/2017/6429410] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 04/28/2017] [Accepted: 07/10/2017] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND In response to international efforts to control and eradicate malaria, we designed this study to give a bibliometric overview of research productivity in antimalarial drug resistance (AMDR). METHODS Keywords related to AMDR were used to retrieve relevant literature using Scopus database. RESULTS A total of 976 publications with an h-index of 63 were retrieved. The number of publications showed a noticeable increase starting in the early 1990s. The USA was the most productive country with 337 publications equivalent to one-third of worldwide publications in this field. More than two-thirds of publications by the USA (236, 70.03%) were made by international collaboration. Of the top ten productive countries, two countries were from Mekong subregion, particularly Thailand and Cambodia. The Malaria Journal was the most productive journal (136, 13.93%) in this field. Mahidol University (80, 8.20%) in Thailand was the most productive institution. Seven articles in the top-ten list were about artemisinin resistance in Plasmodium falciparum, one was about chloroquine resistance, one was about sulfadoxine-pyrimethamine resistance, and the remaining one was about general multidrug resistance. CONCLUSION Eradication and control of AMDR require continuing research activity to help international health organizations identify spots that require an immediate action to implement appropriate measures.
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Affiliation(s)
- Waleed M. Sweileh
- Department of Physiology, Pharmacology and Toxicology, College of Medicine and Health Sciences, An-Najah National University, Nablus, State of Palestine
| | - Samah W. Al-Jabi
- Department of Clinical and Community Pharmacy, College of Medicine and Health Sciences, An-Najah National University, Nablus, State of Palestine
| | - Ansam F. Sawalha
- Department of Physiology, Pharmacology and Toxicology, College of Medicine and Health Sciences, An-Najah National University, Nablus, State of Palestine
| | - Adham S. AbuTaha
- Department of Physiology, Pharmacology and Toxicology, College of Medicine and Health Sciences, An-Najah National University, Nablus, State of Palestine
| | - Sa'ed H. Zyoud
- Department of Clinical and Community Pharmacy, College of Medicine and Health Sciences, An-Najah National University, Nablus, State of Palestine
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16
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Cinnamoylated chloroquine analogues: A new structural class of antimalarial agents. Eur J Med Chem 2017; 135:382-391. [DOI: 10.1016/j.ejmech.2017.04.063] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 04/21/2017] [Accepted: 04/22/2017] [Indexed: 11/22/2022]
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17
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Boyce MR, O'Meara WP. Use of malaria RDTs in various health contexts across sub-Saharan Africa: a systematic review. BMC Public Health 2017; 17:470. [PMID: 28521798 PMCID: PMC5437623 DOI: 10.1186/s12889-017-4398-1] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 05/08/2017] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND The World Health Organization recommends parasitological confirmation of malaria prior to treatment. Malaria rapid diagnostic tests (RDTs) represent one diagnostic method that is used in a variety of contexts to overcome limitations of other diagnostic techniques. Malaria RDTs increase the availability and feasibility of accurate diagnosis and may result in improved quality of care. Though RDTs are used in a variety of contexts, no studies have compared how well or effectively RDTs are used across these contexts. This review assesses the diagnostic use of RDTs in four different contexts: health facilities, the community, drug shops and schools. METHODS A comprehensive search of the Pubmed database was conducted to evaluate RDT execution, test accuracy, or adherence to test results in sub-Saharan Africa. Original RDT and Plasmodium falciparum focused studies conducted in formal health care facilities, drug shops, schools, or by CHWs between the year 2000 and December 2016 were included. Studies were excluded if they were conducted exclusively in a research laboratory setting, where staff from the study team conducted RDTs, or in settings outside of sub-Saharan Africa. RESULTS The literature search identified 757 reports. A total of 52 studies were included in the analysis. Overall, RDTs were performed safely and effectively by community health workers provided they receive proper training. Analogous information was largely absent for formal health care workers. Tests were generally accurate across contexts, except for in drug shops where lower specificities were observed. Adherence to RDT results was higher among drug shop vendors and community health workers, while adherence was more variable among formal health care workers, most notably with negative test results. CONCLUSIONS Malaria RDTs are generally used well, though compliance with test results is variable - especially in the formal health care sector. If low adherence rates are extrapolated, thousands of patients may be incorrectly diagnosed and receive inappropriate treatment resulting in a low quality of care and unnecessary drug use. Multidisciplinary research should continue to explore determinants of good RDT use, and seek to better understand how to support and sustain the correct use of this diagnostic tool.
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Affiliation(s)
| | - Wendy P O'Meara
- Duke Global Health Institute, Durham, NC, USA.,School of Public Health, Moi University College of Health Sciences, Eldoret, Kenya
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18
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Maetani M, Kato N, Jabor VAP, Calil FA, Nonato MC, Scherer CA, Schreiber SL. Discovery of Antimalarial Azetidine-2-carbonitriles That Inhibit P. falciparum Dihydroorotate Dehydrogenase. ACS Med Chem Lett 2017; 8:438-442. [PMID: 28435533 PMCID: PMC5392761 DOI: 10.1021/acsmedchemlett.7b00030] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 02/27/2017] [Indexed: 12/15/2022] Open
Abstract
Dihydroorotate dehydrogenase (DHODH) is an enzyme necessary for pyrimidine biosynthesis in protozoan parasites of the genus Plasmodium, the causative agents of malaria. We recently reported the identification of novel compounds derived from diversity-oriented synthesis with activity in multiple stages of the malaria parasite life cycle. Here, we report the optimization of a potent series of antimalarial inhibitors consisting of azetidine-2-carbonitriles, which we had previously shown to target P. falciparum DHODH in a biochemical assay. Optimized compound BRD9185 (27) has in vitro activity against multidrug-resistant blood-stage parasites (EC50 = 0.016 μM) and is curative after just three doses in a P. berghei mouse model. BRD9185 has a long half-life (15 h) and low clearance in mice and represents a new structural class of DHODH inhibitors with potential as antimalarial drugs.
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Affiliation(s)
- Micah Maetani
- Department of Chemistry
and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
- Broad Institute, Cambridge, Massachusetts 02142, United States
| | - Nobutaka Kato
- Broad Institute, Cambridge, Massachusetts 02142, United States
| | - Valquiria A. P. Jabor
- School of Pharmaceutical Sciences of Ribeirão
Preto, University of São Paulo, Ribeirão Preto, São Paulo 14040-903, Brazil
| | - Felipe A. Calil
- School of Pharmaceutical Sciences of Ribeirão
Preto, University of São Paulo, Ribeirão Preto, São Paulo 14040-903, Brazil
| | - Maria Cristina Nonato
- School of Pharmaceutical Sciences of Ribeirão
Preto, University of São Paulo, Ribeirão Preto, São Paulo 14040-903, Brazil
| | | | - Stuart L. Schreiber
- Department of Chemistry
and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
- Broad Institute, Cambridge, Massachusetts 02142, United States
- Howard Hughes Medical Institute, Cambridge, Massachusetts 02138, United States
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19
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Bergquist R, Utzinger J, Keiser J. Controlling schistosomiasis with praziquantel: How much longer without a viable alternative? Infect Dis Poverty 2017; 6:74. [PMID: 28351414 PMCID: PMC5371198 DOI: 10.1186/s40249-017-0286-2] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/14/2017] [Indexed: 12/11/2022] Open
Abstract
The current approach of morbidity control of schistosomiasis, a helminth disease of poverty with considerable public health and socioeconomic impact, is based on preventive chemotherapy with praziquantel. There is a pressing need for new drugs against this disease whose control entirely depends on this single drug that has been widely used over the past 40 years. We argue that a broader anthelminthic approach supplementing praziquantel with new antischistosomals targeting different parasite development stages would not only increase efficacy but also reduce the risk for drug resistance. Repositioning drugs already approved for other diseases provides a shortcut to clinical trials, as it is expected that such drugs rapidly pass the regulatory authorities. The antischistosomal properties of antimalarial drugs (e.g., semisynthetic artemisinins, synthetic trioxolanes, trioxaquines and mefloquine) and of drugs being developed or registered for other purposes (e.g., moxidectin and miltefosin), administered alone or in combination with praziquantel, have been tested in the laboratory and clinical trials. Another avenue to follow is the continued search for new antischistosomal properties in plants. Here, we summarise recent progress made in schistosomiasis chemotherapy, placing particular emphasis on repositioning of existing drugs against schistosomiasis.
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Affiliation(s)
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, P.O. Box, CH-4002, Basel, Switzerland.,University of Basel, P.O. Box, CH-4003, Basel, Switzerland
| | - Jennifer Keiser
- Swiss Tropical and Public Health Institute, P.O. Box, CH-4002, Basel, Switzerland. .,University of Basel, P.O. Box, CH-4003, Basel, Switzerland.
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20
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Hewitt SN, Dranow DM, Horst BG, Abendroth JA, Forte B, Hallyburton I, Jansen C, Baragaña B, Choi R, Rivas KL, Hulverson MA, Dumais M, Edwards TE, Lorimer DD, Fairlamb AH, Gray DW, Read KD, Lehane AM, Kirk K, Myler PJ, Wernimont A, Walpole C, Stacy R, Barrett LK, Gilbert IH, Van Voorhis WC. Biochemical and Structural Characterization of Selective Allosteric Inhibitors of the Plasmodium falciparum Drug Target, Prolyl-tRNA-synthetase. ACS Infect Dis 2017; 3:34-44. [PMID: 27798837 PMCID: PMC5241706 DOI: 10.1021/acsinfecdis.6b00078] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Plasmodium falciparum (Pf) prolyl-tRNA synthetase (ProRS) is one of the few chemical-genetically validated drug targets for malaria, yet highly selective inhibitors have not been described. In this paper, approximately 40,000 compounds were screened to identify compounds that selectively inhibit PfProRS enzyme activity versus Homo sapiens (Hs) ProRS. X-ray crystallography structures were solved for apo, as well as substrate- and inhibitor-bound forms of PfProRS. We identified two new inhibitors of PfProRS that bind outside the active site. These two allosteric inhibitors showed >100 times specificity for PfProRS compared to HsProRS, demonstrating this class of compounds could overcome the toxicity related to HsProRS inhibition by halofuginone and its analogues. Initial medicinal chemistry was performed on one of the two compounds, guided by the cocrystallography of the compound with PfProRS, and the results can instruct future medicinal chemistry work to optimize these promising new leads for drug development against malaria.
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Affiliation(s)
- Stephen Nakazawa Hewitt
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
| | - David M. Dranow
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Beryllium Discovery Corporation, 7869 N.E. Day Road West, Bainbridge Island, Washington 98110, United States
| | - Benjamin G. Horst
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
| | - Jan A. Abendroth
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Beryllium Discovery Corporation, 7869 N.E. Day Road West, Bainbridge Island, Washington 98110, United States
| | - Barbara Forte
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Irene Hallyburton
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Chimed Jansen
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Beatriz Baragaña
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Ryan Choi
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
| | - Kasey L. Rivas
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
| | - Matthew A. Hulverson
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
| | - Mitchell Dumais
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
| | - Thomas E. Edwards
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Beryllium Discovery Corporation, 7869 N.E. Day Road West, Bainbridge Island, Washington 98110, United States
| | - Donald D. Lorimer
- Beryllium Discovery Corporation, 7869 N.E. Day Road West, Bainbridge Island, Washington 98110, United States
| | - Alan H. Fairlamb
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - David W. Gray
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Kevin D. Read
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Adele M. Lehane
- Research School of Biology, The Australian National University, Acton, Australian Capital Territory 2601, Australia
| | - Kiaran Kirk
- Research School of Biology, The Australian National University, Acton, Australian Capital Territory 2601, Australia
| | - Peter J. Myler
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, Washington 98109, United States
- Departments of Global Health and Biomedical
Informatics and Medical Education, University of Washington, Seattle, Washington 98195, United States
| | - Amy Wernimont
- Structure-guided Drug Discovery Coalition (SDDC), Structural Genomic Consortium, 101 College Street, MaRS South Tower, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Chris Walpole
- Structure-guided Drug Discovery Coalition (SDDC), Structural Genomic Consortium, 101 College Street, MaRS South Tower, Suite 700, Toronto, Ontario M5G 1L7, Canada
| | - Robin Stacy
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, Washington 98109, United States
| | - Lynn K. Barrett
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
| | - Ian H. Gilbert
- Drug Discovery Unit (DDU), Division of Biological Chemistry and Drug
Discovery, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Wesley C. Van Voorhis
- Center for Emerging
and Reemerging Infectious Disease (CERID), University of Washington, 750 Republican Street, Seattle, Washington 98109, United States
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
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21
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Noukpo MH, Damien GB, Elanga-N'Dille E, Sagna AB, Drame PM, Chaffa E, Boussari O, Corbel V, Akogbéto M, Remoue F. Operational Assessment of Long-Lasting Insecticidal Nets by Using an Anopheles Salivary Biomarker of Human-Vector Contact. Am J Trop Med Hyg 2016; 95:1376-1382. [PMID: 27928087 DOI: 10.4269/ajtmh.15-0541] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 08/19/2016] [Indexed: 01/10/2023] Open
Abstract
The widespread implementation of long-lasting insecticidal nets (LLINs) is a major intervention method for malaria control. Although the LLINs coverage increases, information available on the physical integrity (PI) of implemented LLINs is incomplete. This study aimed to validate human IgG antibody (Ab) response to Anopheles gSG6-P1 salivary peptide antigen, previously demonstrated as a pertinent biomarker of human exposure to Anopheles bites, for evaluating the PI of LLINs in field conditions. We analyzed data from 262 randomly selected children (< 5 years of age) in health districts of Benin. Anti-gSG6-P1 IgG responses were assessed and compared with the PI of LLINs that these same children slept under, and evaluated by the hole index (HI). Specific IgG levels were positively correlated to LLINs HI (r = 0.342; P < 0.0001). According to antipeptide IgG level (i.e., intensity of vector exposure), two categories of LLINs PI were defined: 1) group "HI: [0, 100]" corresponding to LLINs with "good" PI and 2) "HI > 100" corresponding to LLINs with "bad" PI. These results suggest that human Ab response to salivary peptide could be a complementary tool to help defining a standardized threshold of efficacy for LLINs under field use.
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Affiliation(s)
- Mahoutin H Noukpo
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.,UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - Georgia B Damien
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.,UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - Emmanuel Elanga-N'Dille
- UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - André B Sagna
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Papa M Drame
- UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - Evelyne Chaffa
- Programme National de Lutte Contre le Paludisme (PNLP), Ministère de la Santé, Cotonou, Bénin
| | - Olayidé Boussari
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.,UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - Vincent Corbel
- UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin.,Department of Entomology, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Nakhon Pathom, Thailand
| | - Martin Akogbéto
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.,Faculté des Sciences et Techniques (FAST), Université d'Abomey Calavi (UAC), Abomey, Bénin
| | - Franck Remoue
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin. .,UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin.,Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
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22
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Anusha S, Sinha A, Babu Rajeev CP, Chu TTT, Mathai J, Ximei H, Fuchs JE, Shivananju N, Bender A, Preiser PR, Rangappa KS, Basappa, Chandramohanadas R. Synthesis, characterization and in vitro evaluation of novel enantiomerically-pure sulphonamide antimalarials. Org Biomol Chem 2016; 13:10681-90. [PMID: 26347024 DOI: 10.1039/c5ob01479d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Malaria parasites are currently gaining drug-resistance rapidly, across countries and continents. Hence, the discovery and development of novel chemical scaffolds, with superior antimalarial activity remain an important priority, for the developing world. Our report describes the development, characterization and evaluation of novel bepotastine-based sulphonamide antimalarials inhibiting asexual stage development of Plasmodium falciparum parasites in vitro. The screening results showed potent inhibitory activity of a number of novel sulphonamides against P. falciparum at low micromolar concentrations, in particular in late-stage parasite development. Based on computational studies we hypothesize N-myristoyltransferase as the target of the compounds developed here. Our results demonstrate the value of novel bepotastine-based sulphonamide compounds for targeting the asexual developmental stages of P. falciparum.
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Affiliation(s)
- Sebastian Anusha
- Laboratory of Chemical Biology, Department of Chemistry, Bangalore University, Bangalore, India.
| | - Ameya Sinha
- Pillar of Engineering Product Development, Singapore University of Technology & Design, Singapore.
| | - C P Babu Rajeev
- Laboratory of Chemical Biology, Department of Chemistry, Bangalore University, Bangalore, India.
| | - Trang T T Chu
- Pillar of Engineering Product Development, Singapore University of Technology & Design, Singapore.
| | - Jessin Mathai
- Gulf Medical University, Ajman, United Arab Emirates
| | - Huang Ximei
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Julian E Fuchs
- Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK and Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innrain 82, 6020 Innsbruck, Austria
| | | | - Andreas Bender
- Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK
| | | | | | - Basappa
- Laboratory of Chemical Biology, Department of Chemistry, Bangalore University, Bangalore, India.
| | - Rajesh Chandramohanadas
- Pillar of Engineering Product Development, Singapore University of Technology & Design, Singapore.
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23
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Caljon G, De Muylder G, Durnez L, Jennes W, Vanaerschot M, Dujardin JC. Alice in microbes' land: adaptations and counter-adaptations of vector-borne parasitic protozoa and their hosts. FEMS Microbiol Rev 2016; 40:664-85. [PMID: 27400870 DOI: 10.1093/femsre/fuw018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2016] [Indexed: 12/24/2022] Open
Abstract
In the present review, we aim to provide a general introduction to different facets of the arms race between pathogens and their hosts/environment, emphasizing its evolutionary aspects. We focus on vector-borne parasitic protozoa, which have to adapt to both invertebrate and vertebrate hosts. Using Leishmania, Trypanosoma and Plasmodium as main models, we review successively (i) the adaptations and counter-adaptations of parasites and their invertebrate host, (ii) the adaptations and counter-adaptations of parasites and their vertebrate host and (iii) the impact of human interventions (chemotherapy, vaccination, vector control and environmental changes) on these adaptations. We conclude by discussing the practical impact this knowledge can have on translational research and public health.
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Affiliation(s)
- Guy Caljon
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium University of Antwerp, Department of Biomedical Sciences, Laboratory of Microbiology, Parasitology and Health, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - Géraldine De Muylder
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Lies Durnez
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Wim Jennes
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Manu Vanaerschot
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium Columbia University, College of Physicians and Surgeons, Department of Microbiology and Immunology, Fidock Lab, New York, NY 10032, USA
| | - Jean-Claude Dujardin
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium University of Antwerp, Department of Biomedical Sciences, Laboratory of Microbiology, Parasitology and Health, Universiteitsplein 1, B-2610 Wilrijk, Belgium
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24
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Globally prevalent PfMDR1 mutations modulate Plasmodium falciparum susceptibility to artemisinin-based combination therapies. Nat Commun 2016; 7:11553. [PMID: 27189525 PMCID: PMC4873939 DOI: 10.1038/ncomms11553] [Citation(s) in RCA: 186] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 04/07/2016] [Indexed: 02/07/2023] Open
Abstract
Antimalarial chemotherapy, globally reliant on artemisinin-based combination therapies (ACTs), is threatened by the spread of drug resistance in Plasmodium falciparum parasites. Here we use zinc-finger nucleases to genetically modify the multidrug resistance-1 transporter PfMDR1 at amino acids 86 and 184, and demonstrate that the widely prevalent N86Y mutation augments resistance to the ACT partner drug amodiaquine and the former first-line agent chloroquine. In contrast, N86Y increases parasite susceptibility to the partner drugs lumefantrine and mefloquine, and the active artemisinin metabolite dihydroartemisinin. The PfMDR1 N86 plus Y184F isoform moderately reduces piperaquine potency in strains expressing an Asian/African variant of the chloroquine resistance transporter PfCRT. Mutations in both digestive vacuole-resident transporters are thought to differentially regulate ACT drug interactions with host haem, a product of parasite-mediated haemoglobin degradation. Global mapping of these mutations illustrates where the different ACTs could be selectively deployed to optimize treatment based on regional differences in PfMDR1 haplotypes. Antimalarial chemotherapy relies on combination therapies (ACTs) consisting of an artemisinin derivative and a partner drug. Here, the authors study the effects of globally prevalent mutations in a multidrug resistance transporter (PfMDR1) on the parasite's susceptibility to ACT drugs.
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25
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Gonçalves D, Hunziker P. Transmission-blocking strategies: the roadmap from laboratory bench to the community. Malar J 2016; 15:95. [PMID: 26888537 PMCID: PMC4758146 DOI: 10.1186/s12936-016-1163-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Accepted: 02/11/2016] [Indexed: 11/10/2022] Open
Abstract
Malaria remains one of the most prevalent tropical and infectious diseases in the world, with an estimated more than 200 million clinical cases every year. In recent years, the mosquito stages of the parasite life cycle have received renewed attention with some progress being made in the development of transmission-blocking strategies. From gametocytes to late ookinetes, some attractive antigenic targets have been found and tested in order to develop a transmission blocking vaccine, and drugs are being currently screened for gametocytocidal activity, and also some new and less conventional approaches are drawing increased attention, such as genetically modified and fungus-infected mosquitoes that become refractory to Plasmodium infection. In this review some of those strategies focusing on the progress made so far will be summarized, but also, the challenges that come from the translation of early promising benchwork resulting in successful applications in the field. To do this, the available literature will be screened and all the pieces of the puzzle must be combined: from molecular biology to epidemiologic and clinical data.
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Affiliation(s)
- Daniel Gonçalves
- CLINAM Foundation for Nanomedicine, University of Basel, Basel, Switzerland.
| | - Patrick Hunziker
- CLINAM Foundation for Nanomedicine, University of Basel, Basel, Switzerland.
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Shamriz S, Ofoghi H. Design, structure prediction and molecular dynamics simulation of a fusion construct containing malaria pre-erythrocytic vaccine candidate, PfCelTOS, and human interleukin 2 as adjuvant. BMC Bioinformatics 2016; 17:71. [PMID: 26851942 PMCID: PMC4744421 DOI: 10.1186/s12859-016-0918-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 01/29/2016] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Malaria infection is still widespread in some parts of the world and threatens the lives of millions of people every year. Vaccines, especially oral vaccines are considered to be effective in reducing the burden of malaria morbidity and mortality. By using recombinant technology, suitable oral hosts could serve as antigen delivering vehicles in developing oral vaccines. This study was aimed towards designing and computational analysis of a fusion protein consisting of Plasmodium falciparum cell-traversal protein for ookinetes and sporozoites (PfCelTOS) fused to human interleukin-2 (IL-2) and M cell-specific peptide ligand (Co1), as a step toward developing a vaccine candidate. RESULTS To our best knowledge, the three dimensional (3D) structure of CelTOS is not reported in protein database. Therefore, we carried out computational modeling and simulation in the hope of understanding the properties and structure of PfCelTOS. Then we fused IL-2 to PfCelTOS by a flexible linker and did in silico analysis to confirm the proper folding of each domain in the designed fusion protein. In the last step, Co1 ligand was added to the confirmed fusion structure using a rigid linker and computational analysis was performed to evaluate the final fusion construct. One structure out of five predicted by I-TASSER for PfCelTOS and fusion constructs was selected based on the highest value for C-score. Molecular dynamics (MD) simulation analysis indicated that predicted structures are stable during the simulation. Ramchandran Plot analysis of PfCelTOS and fusion constructs before and after MD simulation also represented that most residues were fallen in favorable regions. CONCLUSION In silico study showed that Co1-(AEEEK)3- IL-2-(GGGGS)3-PfCelTOS construct has a constant structure and the selected linkers are effectively able to separate the domains. Therefore, data reported in this paper represents the first step toward developing of an oral vaccine candidate against malaria infection.
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Affiliation(s)
- Shabnam Shamriz
- Department of Biotechnology, Iranian Research Organization for Science and Technology, Tehran, Iran.
| | - Hamideh Ofoghi
- Department of Biotechnology, Iranian Research Organization for Science and Technology, Tehran, Iran.
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Kondaparla S, Soni A, Manhas A, Srivastava K, Puri SK, Katti SB. Synthesis and antimalarial activity of new 4-aminoquinolines active against drug resistant strains. RSC Adv 2016. [DOI: 10.1039/c6ra14016e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In the present study we have synthesized a new class of 4-aminoquinoline derivatives and bioevaluated them for antimalarial activity against theP. falciparum in vitro(3D7 & K1) andP. yoelii in vivo(N-67 strain).
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Affiliation(s)
- Srinivasarao Kondaparla
- Medicinal & Process Chemistry Division
- CSIR-Central Drug Research Institute
- Lucknow-226031
- India
| | - Awakash Soni
- Parasitology Division
- CSIR-Central Drug Research Institute
- Lucknow-226031
- India
| | - Ashan Manhas
- Parasitology Division
- CSIR-Central Drug Research Institute
- Lucknow-226031
- India
| | - Kumkum Srivastava
- Parasitology Division
- CSIR-Central Drug Research Institute
- Lucknow-226031
- India
| | - Sunil K. Puri
- Parasitology Division
- CSIR-Central Drug Research Institute
- Lucknow-226031
- India
| | - S. B. Katti
- Medicinal & Process Chemistry Division
- CSIR-Central Drug Research Institute
- Lucknow-226031
- India
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Yadav L, Tiwari MK, Kumar Shyamlal BR, Mathur M, Swami AK, Puri SK, Naikade NK, Chaudhary S. Synthesis and antimalarial activity of novel bicyclic and tricyclic aza-peroxides. RSC Adv 2016. [DOI: 10.1039/c5ra16781g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Bicyclic and tricyclic aza-peroxides were synthesized and assessed for theirin vitroandin vivoantimalarial activities againstPlasmodium falciparum(3D7 strain) andPlasmodium yoelii nigeriensisin Swiss mice by an oral route, respectively.
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Affiliation(s)
- Lalit Yadav
- Department of Chemistry
- Malaviya National Institute of Technology
- Jawaharlal Nehru Marg
- Jaipur-302017
- India
| | - Mohit K. Tiwari
- Department of Chemistry
- Malaviya National Institute of Technology
- Jawaharlal Nehru Marg
- Jaipur-302017
- India
| | | | - Manas Mathur
- Department of Advance Molecular Microbiology
- Seminal Applied Sciences Pvt. Ltd
- Jaipur-302015
- India
| | - Ajit K. Swami
- Department of Advance Molecular Microbiology
- Seminal Applied Sciences Pvt. Ltd
- Jaipur-302015
- India
| | - Sunil K. Puri
- Division of Parasitology
- CSIR-Central Drug Research Institute
- Lucknow-226031
- India
| | - Niraj K. Naikade
- Division of Medicinal and Process Chemistry
- CSIR-Central Drug Research Institute
- Lucknow-226031
- India
- Sandoz India Pvt. Ltd
| | - Sandeep Chaudhary
- Department of Chemistry
- Malaviya National Institute of Technology
- Jawaharlal Nehru Marg
- Jaipur-302017
- India
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Haem-activated promiscuous targeting of artemisinin in Plasmodium falciparum. Nat Commun 2015; 6:10111. [PMID: 26694030 PMCID: PMC4703832 DOI: 10.1038/ncomms10111] [Citation(s) in RCA: 400] [Impact Index Per Article: 44.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 11/04/2015] [Indexed: 12/17/2022] Open
Abstract
The mechanism of action of artemisinin and its derivatives, the most potent of the anti-malarial drugs, is not completely understood. Here we present an unbiased chemical proteomics analysis to directly explore this mechanism in Plasmodium falciparum. We use an alkyne-tagged artemisinin analogue coupled with biotin to identify 124 artemisinin covalent binding protein targets, many of which are involved in the essential biological processes of the parasite. Such a broad targeting spectrum disrupts the biochemical landscape of the parasite and causes its death. Furthermore, using alkyne-tagged artemisinin coupled with a fluorescent dye to monitor protein binding, we show that haem, rather than free ferrous iron, is predominantly responsible for artemisinin activation. The haem derives primarily from the parasite's haem biosynthesis pathway at the early ring stage and from haemoglobin digestion at the latter stages. Our results support a unifying model to explain the action and specificity of artemisinin in parasite killing. The mechanism of action of artemisinin, an antimalarial drug, is not well understood. Here, the authors use a labelled artemisinin analogue to show that the drug is mainly activated by haem and then binds covalently to over 120 proteins in the malaria parasite, affecting many of its cellular processes.
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Chaudhary S, Sharma V, Jaiswal PK, Gaikwad AN, Sinha SK, Puri SK, Sharon A, Maulik PR, Chaturvedi V. Stable Tricyclic Antitubercular Ozonides Derived from Artemisinin. Org Lett 2015; 17:4948-51. [DOI: 10.1021/acs.orglett.5b02296] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sandeep Chaudhary
- Department of Chemistry & Materials Research Centre, Malaviya National Institute of Technology, Jawaharlal Nehru Marg, Jaipur 302017, India
| | - Vashundhra Sharma
- Department of Chemistry & Materials Research Centre, Malaviya National Institute of Technology, Jawaharlal Nehru Marg, Jaipur 302017, India
| | - Pradeep K. Jaiswal
- Department of Chemistry & Materials Research Centre, Malaviya National Institute of Technology, Jawaharlal Nehru Marg, Jaipur 302017, India
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Shibi I, Aswathy L, Jisha R, Masand V, Divyachandran A, Gajbhiye J. Molecular docking and QSAR analyses for understanding the antimalarial activity of some 7-substituted-4-aminoquinoline derivatives. Eur J Pharm Sci 2015; 77:9-23. [DOI: 10.1016/j.ejps.2015.05.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/02/2015] [Accepted: 05/21/2015] [Indexed: 12/28/2022]
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Abstract
The development of resistance to existing antimicrobials has created a threat to human health that is not being addressed through our current drug pipeline. Limitations with the use of commercial vendor libraries and natural products have created a need for new types of small molecules to be screened in antimicrobial assays. Diversity oriented synthesis (DOS) is a strategy for the efficient generation of compound collections with a high degree of structural diversity. Diversity-oriented synthesis molecules occupy the middle ground of both complexity and efficiency of synthesis between natural products and commercial libraries. In this review we focus upon the use of diversity-oriented synthesis compound collections for the discovery of new antimicrobial agents.
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Mongui A, Pérez-Llanos FJ, Yamamoto MM, Lozano M, Zambrano MM, Del Portillo P, Fernández-Becerra C, Restrepo S, Del Portillo HA, Junca H. Development of a genetic tool for functional screening of anti-malarial bioactive extracts in metagenomic libraries. Malar J 2015; 14:233. [PMID: 26040274 PMCID: PMC4464701 DOI: 10.1186/s12936-015-0748-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 05/26/2015] [Indexed: 12/25/2022] Open
Abstract
Background The chemical treatment of Plasmodium falciparum for human infections is losing efficacy each year due to the rise of resistance. One possible strategy to find novel anti-malarial drugs is to access the largest reservoir of genomic biodiversity source on earth present in metagenomes of environmental microbial communities. Methods A bioluminescent P. falciparum parasite was used to quickly detect shifts in viability of microcultures grown in 96-well plates. A synthetic gene encoding the Dermaseptin 4 peptide was designed and cloned under tight transcriptional control in a large metagenomic insert context (30 kb) to serve as proof-of-principle for the screening platform. Results Decrease in parasite viability consistently correlated with bioluminescence emitted from parasite microcultures, after their exposure to bacterial extracts containing a plasmid or fosmid engineered to encode the Dermaseptin 4 anti-malarial peptide. Conclusions Here, a new technical platform to access the anti-malarial potential in microbial environmental metagenomes has been developed.
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Affiliation(s)
- Alvaro Mongui
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia. .,Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia.
| | - Francy J Pérez-Llanos
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia. .,Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia.
| | - Marcio M Yamamoto
- Departamento de Parasitologia, Universidade de São Paulo, São Paulo, Brazil.
| | - Marcela Lozano
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia.
| | - Maria M Zambrano
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia.
| | - Patricia Del Portillo
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia.
| | - Carmen Fernández-Becerra
- ICREA at ISGlobal, Barcelona Ctr Int Health Res (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.
| | - Silvia Restrepo
- Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia.
| | - Hernando A Del Portillo
- ICREA at ISGlobal, Barcelona Ctr Int Health Res (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain. .,Institució Catalana de Recerca I Estudis Avançats (ICREA), Barcelona, Spain.
| | - Howard Junca
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia. .,Present Address: Applied Biology Program, Faculty of Basic & Applied Sciences, Universidad Militar Nueva Granada-UMNG, Campus Cajicá, Bogotá, DC, Colombia.
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Raj R, Saini A, Gut J, Rosenthal PJ, Kumar V. Synthesis and in vitro antiplasmodial evaluation of 7-chloroquinoline–chalcone and 7-chloroquinoline–ferrocenylchalcone conjugates. Eur J Med Chem 2015; 95:230-9. [DOI: 10.1016/j.ejmech.2015.03.045] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 03/18/2015] [Accepted: 03/19/2015] [Indexed: 11/28/2022]
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From hybrid compounds to targeted drug delivery in antimalarial therapy. Bioorg Med Chem 2015; 23:5120-30. [PMID: 25913864 DOI: 10.1016/j.bmc.2015.04.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 04/01/2015] [Accepted: 04/07/2015] [Indexed: 11/21/2022]
Abstract
The discovery of new drugs to treat malaria is a continuous effort for medicinal chemists due to the emergence and spread of resistant strains of Plasmodium falciparum to nearly all used antimalarials. The rapid adaptation of the malaria parasite remains a major limitation to disease control. Development of hybrid antimalarial agents has been actively pursued as a promising strategy to overcome the emergence of resistant parasite strains. This review presents the journey that started with simple combinations of two active moieties into one chemical entity and progressed into a delivery/targeted system based on major antimalarial classes of drugs. The rationale for providing different mechanisms of action against a single or additional targets involved in the multiple stages of the parasite's life-cycle is highlighted. Finally, a perspective for this polypharmacologic approach is presented.
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Liu H, Yang HL, Tang LH, Li XL, Huang F, Wang JZ, Li CF, Wang HY, Nie RH, Guo XR, Lin YX, Li M, Wang J, Xu JW. In vivo monitoring of dihydroartemisinin-piperaquine sensitivity in Plasmodium falciparum along the China-Myanmar border of Yunnan Province, China from 2007 to 2013. Malar J 2015; 14:47. [PMID: 25652213 PMCID: PMC4333884 DOI: 10.1186/s12936-015-0584-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 01/25/2015] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Artemisinin-based combination therapy (ACT) is the recommended first-line treatment of falciparum malaria in all endemic countries. Artemisinin resistance in Plasmodium falciparum has been confirmed in the Greater Mekong subregion (GMS). Dihydroartemisinin-piperaquine (DAPQ) is the most commonly used ACT in China. To understand the DAPQ sensitivity of P. falciparum, DAPQ resistance was monitored in vivo along the China-Myanmar border from 2007 to 2013. METHODS Eligible patients with mono-infections of P. falciparum were recruited to this study after obtaining full informed consent. DAPQ tablets for different categories of kg body weight ranges were given once a day for three days. Patients were followed up for 42 days. Polymerase chain reaction (PCR) was conducted to distinguish between re-infection and recrudescence, to confirm the Plasmodium species. The data were entered and analysed by the Kaplan-Meier method. Treatment outcome was assessed according to the WHO recommended standards. RESULTS 243 patients were completed valid follow-up. The fever clearance time (FCT) and asexual parasite clearance times (APCT) were, respectively, 36.5 ± 10.9 and 43.5 ± 11.8 hours, and there was an increasing trend of both FCT (F = 268.41, P < 0.0001) and APCT (F = 88.6, P < 0.0001) from 2007 to 2013. Eight (3.3%, 95% confidence interval, 1.4-6.4%) patients present parasitaemia on day three after medication; however they were spontaneous cure on day four. 241 (99.2%; 95% CI, 97.1-99.9%) of the patients were adequate clinical and parasitological response (ACPR) and the proportions of ACPR had not changed significantly from 2007 to 2013 (X(2) = 2.81, P = 0.7288). CONCLUSION In terms of efficacy, DAPQ is still an effective treatment for falciparum malaria. DAPQ sensitivity in P. falciparum had not significantly changed along the China-Myanmar border of Yunnan Province, China. However more attentions should be given to becoming slower fever and parasite clearance.
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Affiliation(s)
- Hui Liu
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Heng-lin Yang
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Lin-hua Tang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, PR China.
| | - Xing-liang Li
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Fang Huang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, PR China.
| | - Jia-zhi Wang
- Tengchong County Center for Disease Control and Prevention, Tengchong, 679100, China.
| | - Chun-fu Li
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Heng-ye Wang
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Ren-hua Nie
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Xiang-rui Guo
- Yangjiang County Center for Disease Control and Prevention, Yingjiang, 679300, China.
| | - Ying-xue Lin
- Yangjiang County Center for Disease Control and Prevention, Yingjiang, 679300, China.
| | - Mei Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, PR China.
| | - Jian Wang
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Jian-wei Xu
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
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Marie A, Ronca R, Poinsignon A, Lombardo F, Drame PM, Cornelie S, Besnard P, Le Mire J, Fiorentino G, Fortes F, Carnevale P, Remoue F, Arcà B. The Anopheles gambiae cE5 salivary protein: a sensitive biomarker to evaluate the efficacy of insecticide-treated nets in malaria vector control. Microbes Infect 2015; 17:409-16. [PMID: 25637950 DOI: 10.1016/j.micinf.2015.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 01/21/2015] [Accepted: 01/22/2015] [Indexed: 11/26/2022]
Abstract
Evaluation of vector control is crucial for improving malaria containment and, according to World Health Organization, new complementary indicators would be very valuable. In this study the IgG response to the Anopheles-specific cE5 salivary protein was tested as a tool to evaluate the efficacy of insecticide-treated nets in reducing human exposure to malaria vectors. Sera collected during a longitudinal study carried out in Angola, and including entomological and parasitological data, were used to assess the IgG response to the Anopheles gambiae cE5 in both children and adults, before and after the application of insecticide-treated nets. Seasonal fluctuation of specific IgG antibody levels according to exposure was only found in children (up to ≈ 14 years old) whose anti-cE5 IgG response dropped after bed nets installation. These results were fully consistent with previous findings obtained with the same set of sera and indicating a substantial reduction of human-vector contact shortly after nets implementation. Overall, children IgG response to the cE5 protein appeared a very sensitive biomarker, which allowed for the detection of even weak exposure to Anopheles bites, indicating it may represent a reliable additional tool to evaluate the efficacy of vector control interventions.
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Affiliation(s)
- Alexandra Marie
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France.
| | - Raffaele Ronca
- Department of Biology, "Federico II" University, Via Cinthia, 80126 Naples, Italy
| | - Anne Poinsignon
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France
| | - Fabrizio Lombardo
- Department of Public Health and Infectious Diseases, Parasitology Section, Sapienza University, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Papa M Drame
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France
| | - Sylvie Cornelie
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France; MIVEGEC-IRD-CREC, 01 BP44 RP Cotonou, Benin
| | | | | | - Gabriella Fiorentino
- Department of Biology, "Federico II" University, Via Cinthia, 80126 Naples, Italy
| | - Filomeno Fortes
- Malaria Control Program, Ministry of Public Health, Luanda, Angola
| | | | - Franck Remoue
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France
| | - Bruno Arcà
- Department of Public Health and Infectious Diseases, Parasitology Section, Sapienza University, Piazzale Aldo Moro 5, 00185 Rome, Italy.
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Arteether nanoemulsion for enhanced efficacy against Plasmodium yoelii nigeriensis malaria: an approach by enhanced bioavailability. Colloids Surf B Biointerfaces 2015; 126:467-75. [PMID: 25616971 DOI: 10.1016/j.colsurfb.2014.12.052] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 12/05/2014] [Accepted: 12/30/2014] [Indexed: 11/21/2022]
Abstract
The present work is focused on the preparation of nanoemulsions (NEs) loaded with arteether (ART) for its enhanced efficacy against malaria parasites. ART-NEs have been prepared using high pressure homogenization (HPH) technique with the aim of improving its solubility and thus its bioavailability. ART-NEs were optimized in terms of pressure and number of cycles. Globule size and size distributions were chosen as quality parameters. The maximum drug loading was achieved up to 93 ± 7.4% with globule size 156 ± 10.2 nm and zeta potential of -23.3 ± 3.4 mV. The developed ART-NEs were found to be stable in terms of globule size and size distribution at different pH. The in vitro release profile of the ART-NEs showed 62% drug release within 12h. The percentage cell viability of blank NEs were within acceptable limits. A sensitive assay method for the determination of ART in rat plasma by liquid chromatography-mass spectrometry (LC-MS) was employed after oral administration of ART-NEs. The pharmacokinetic study showed significantly enhanced bioavailability of ART in ART-NE-V. The area under curve (AUC) of ART-NE-V was AUC0-t 1988.411 ± 119.66 h ng/ml which was significantly higher (p<0.05) than ART in ground nut oil (GNO) AUC0-t 671.852 ± 187.05 h ng/ml. The Cmax of ART-NE-V (1506 ± 161.22 ng/ml) was also significantly higher (p<0.05) than ART in GNO (175.2 ± 16.54 ng/ml) and ART given intramuscularly (IM) (278.05 ± 38.59 ng/ml). The ART-NE-V was having significantly high antimalarial efficacy and survival rate of mice giving 80% cure rate at 12.5 mg/kg for 5 days in comparison to 30% cure rate of ART in GNO at the same daily dose and it was also comparable to the 100% cure rate at 12.5 mg/kg for 5 days for ART given intramuscularly. In conclusion ART-NE can be a promising oral delivery system for ART.
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Marie A, Holzmuller P, Tchioffo MT, Rossignol M, Demettre E, Seveno M, Corbel V, Awono-Ambéné P, Morlais I, Remoue F, Cornelie S. Anopheles gambiae salivary protein expression modulated by wild Plasmodium falciparum infection: highlighting of new antigenic peptides as candidates of An. gambiae bites. Parasit Vectors 2014; 7:599. [PMID: 25526764 PMCID: PMC4287575 DOI: 10.1186/s13071-014-0599-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 12/10/2014] [Indexed: 12/24/2022] Open
Abstract
Background Malaria is the major parasitic disease worldwide caused by Plasmodium infection. The objective of integrated malaria control programs is to decrease malaria transmission, which needs specific tools to be accurately assessed. In areas where the transmission is low or has been substantially reduced, new complementary tools have to be developed to improve surveillance. A recent approach, based on the human antibody response to Anopheles salivary proteins, has been shown to be efficient in evaluating human exposure to Anopheles bites. The aim of the present study was to identify new An. gambiae salivary proteins as potential candidate biomarkers of human exposure to P. falciparum-infective bites. Methods Experimental infections of An. gambiae by wild P. falciparum were carried out in semi-field conditions. Then a proteomic approach, combining 2D-DIGE and mass spectrometry, was used to identify the overexpressed salivary proteins in infected salivary glands compared to uninfected An. gambiae controls. Subsequently, a peptide design of each potential candidate was performed in silico and their antigenicity was tested by an epitope-mapping technique using blood from individuals exposed to Anopheles bites. Results Five salivary proteins (gSG6, gSG1b, TRIO, SG5 and long form D7) were overexpressed in the infected salivary glands. Eighteen peptides were designed from these proteins and were found antigenic in children exposed to the Anopheles bites. Moreover, the results showed that the presence of wild P. falciparum in salivary glands modulates the expression of several salivary proteins and also appeared to induce post-translational modifications. Conclusions This study is, to our knowledge, the first that compares the sialome of An. gambiae both infected and not infected by wild P. falciparum, making it possible to mimic the natural conditions of infection. This is a first step toward a better understanding of the close interactions between the parasite and the salivary gland of mosquitoes. In addition, these results open the way to define biomarkers of infective bites of Anopheles, which could, in the future, improve the estimation of malaria transmission and the evaluation of malaria vector control tools. Electronic supplementary material The online version of this article (doi:10.1186/s13071-014-0599-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alexandra Marie
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France.
| | - Philippe Holzmuller
- CIRAD Département Systèmes Biologiques BIOS UMR 15 CMAEE "Contrôle des Maladies Exotiques et Emergentes", Campus International de Baillarguet, TA A-15/G, Montpellier cedex 5, 34398, France.
| | - Majoline T Tchioffo
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France.
| | - Marie Rossignol
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France.
| | - Edith Demettre
- Institut de Génomique Fonctionnelle, CNRS UMR 5203, INSERM U661, UM1, UM2, Plate-forme de Protéomique Fonctionnelle CNRS UMS BioCampus 3426, Montpellier, 34094, France.
| | - Martial Seveno
- Institut de Génomique Fonctionnelle, CNRS UMR 5203, INSERM U661, UM1, UM2, Plate-forme de Protéomique Fonctionnelle CNRS UMS BioCampus 3426, Montpellier, 34094, France.
| | - Vincent Corbel
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France. .,Department of Entomology, Faculty of Agriculture, Kasetsart University, 50 Ngam Wong Wan Rd, Ladyaow Chatuchak, Bangkok, 10900, Thailand.
| | - Parfait Awono-Ambéné
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, BP 288, Cameroun.
| | - Isabelle Morlais
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France. .,Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, BP 288, Cameroun.
| | - Franck Remoue
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France.
| | - Sylvie Cornelie
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France. .,MIVEGEC- IRD- CREC, Cotonou, 01 BP4414 RP, Bénin.
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Mohon AN, Alam MS, Bayih AG, Folefoc A, Shahinas D, Haque R, Pillai DR. Mutations in Plasmodium falciparum K13 propeller gene from Bangladesh (2009-2013). Malar J 2014; 13:431. [PMID: 25404021 PMCID: PMC4240861 DOI: 10.1186/1475-2875-13-431] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 11/03/2014] [Indexed: 12/22/2022] Open
Abstract
Background Bangladesh is a malaria hypo-endemic country sharing borders with India and Myanmar. Artemisinin combination therapy (ACT) remains successful in Bangladesh. An increase of artemisinin-resistant malaria parasites on the Thai-Cambodia and Thai-Myanmar borders is worrisome. K13 propeller gene (PF3D7_1343700 or PF13_0238) mutations have been linked to both in vitro artemisinin resistance and in vivo slow parasite clearance rates. This group undertook to evaluate if mutations seen in Cambodia have emerged in Bangladesh where ACT use is now standard for a decade. Methods Samples were obtained from Plasmodium falciparum-infected malaria patients from Upazila health complexes (UHC) between 2009 and 2013 in seven endemic districts of Bangladesh. These districts included Khagrachari (Matiranga UHC), Rangamati (Rajasthali UHC), Cox’s Bazar (Ramu and Ukhia UHC), Bandarban (Lama UHC), Mymensingh (Haluaghat UHC), Netrokona (Durgapur and Kalmakanda UHC), and Moulvibazar (Sreemangal and Kamalganj UHC). Results Out of 296 microscopically positive P. falciparum samples, 271 (91.6%) were confirmed as mono-infections by both real-time PCR and nested PCR. The K13 propeller gene from 253 (93.4%) samples was sequenced bi-directionally. One non-synonymous mutation (A578S) was found in Bangladeshi clinical isolates. The A578S mutation was confirmed and lies adjacent to the C580Y mutation, the major mutation causing delayed parasite clearance in Cambodia. Based on computational modeling A578S should have a significant effect on tertiary structure of the protein. Conclusion The data suggest that P. falciparum in Bangladesh remains free of the C580Y mutation linked to delayed parasite clearance. However, the mutation A578S is present and based on structural analysis could affect K13 gene function. Further in vivo clinical studies are required to validate the effect of this mutation.
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Affiliation(s)
| | | | | | | | | | | | - Dylan R Pillai
- Department of Microbiology, Immunology and Infectious Diseases, Faculty of Medicine, University of Calgary, Diagnostic and Scientific Centre, Room 1 W-416, 9-3535 Research Road NW, Calgary, AB T2L 2 K8, Canada.
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In silico screening for Plasmodium falciparum enoyl-ACP reductase inhibitors. J Comput Aided Mol Des 2014; 29:79-87. [PMID: 25344312 DOI: 10.1007/s10822-014-9806-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 10/17/2014] [Indexed: 10/24/2022]
Abstract
The need for novel therapeutics against Plasmodium falciparum is urgent due to recent emergence of multi-drug resistant malaria parasites. Since fatty acids are essential for both the liver and blood stages of the malarial parasite, targeting fatty acid biosynthesis is a promising strategy for combatting P. falciparum. We present a combined computational and experimental study to identify novel inhibitors of enoyl-acyl carrier protein reductase (PfENR) in the fatty acid biosynthesis pathway. A small-molecule database from ChemBridge was docked into three distinct PfENR crystal structures that provide multiple receptor conformations. Two different docking algorithms were used to generate a consensus score in order to rank possible small molecule hits. Our studies led to the identification of five low-micromolar pyrimidine dione inhibitors of PfENR.
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Comer E, Beaudoin JA, Kato N, Fitzgerald ME, Heidebrecht RW, Lee MD, Masi D, Mercier M, Mulrooney C, Muncipinto G, Rowley A, Crespo-Llado K, Serrano AE, Lukens AK, Wiegand RC, Wirth DF, Palmer MA, Foley MA, Munoz B, Scherer CA, Duvall JR, Schreiber SL. Diversity-oriented synthesis-facilitated medicinal chemistry: toward the development of novel antimalarial agents. J Med Chem 2014; 57:8496-502. [PMID: 25211597 PMCID: PMC4207553 DOI: 10.1021/jm500994n] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
![]()
Here, we describe medicinal chemistry
that was accelerated by a
diversity-oriented synthesis (DOS) pathway, and in vivo studies of our previously reported macrocyclic antimalarial agent
that derived from the synthetic pathway. Structure–activity
relationships that focused on both appendage and skeletal features
yielded a nanomolar inhibitor of P. falciparum asexual
blood-stage growth with improved solubility and microsomal stability
and reduced hERG binding. The build/couple/pair (B/C/P) synthetic
strategy, used in the preparation of the original screening library,
facilitated medicinal chemistry optimization of the antimalarial lead.
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Affiliation(s)
- Eamon Comer
- Center for the Science of Therapeutics, Broad Institute , 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
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Mohapatra PK, Sarma DK, Prakash A, Bora K, Ahmed MA, Sarma B, Goswami BK, Bhattacharyya DR, Mahanta J. Molecular evidence of increased resistance to anti-folate drugs in Plasmodium falciparum in North-East India: a signal for potential failure of artemisinin plus sulphadoxine-pyrimethamine combination therapy. PLoS One 2014; 9:e105562. [PMID: 25184337 PMCID: PMC4153584 DOI: 10.1371/journal.pone.0105562] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 07/24/2014] [Indexed: 01/16/2023] Open
Abstract
North-east India, being a corridor to South-east Asia, is believed to play an important role in transmitting drug resistant Plasmodium falciparum malaria to India and South Asia. North-east India was the first place in India to record the emergence of drug resistance to chloroquine as well as sulphadoxine/pyrimethamine. Presently chloroquine resistance is widespread all over the North-east India and resistance to other anti-malarials is increasing. In this study both in vivo therapeutic efficacy and molecular assays were used to screen the spectrum of drug resistance to chloroquine and sulphadoxine/pyrimethamine in the circulating P. falciparum strains. A total of 220 P. falciparum positives subjects were enrolled in the study for therapeutic assessment of chloroquine and sulphadoxine/pyrimethamine and assessment of point mutations conferring resistances to these drugs were carried out by genotyping the isolates following standard methods. Overall clinical failures in sulphadoxine/pyrimethamine and chloroquine were found 12.6 and 69.5% respectively, while overall treatment failures recorded were 13.7 and 81.5% in the two arms. Nearly all (99.0%) the isolates had mutant pfcrt genotype (76 T), while 68% had mutant pfmdr-1 genotype (86 Y). Mutation in dhps 437 codon was the most prevalent one while dhfr codon 108 showed 100% mutation. A total of 23 unique haplotypes at the dhps locus and 7 at dhfr locus were found while dhps-dhfr combined loci revealed 49 unique haplotypes. Prevalence of double, triple and quadruple mutations were common while 1 haplotype was found with all five mutated codons (F/AGEGS/T) at dhps locus. Detection of quadruple mutants (51 I/59 R/108 N/164 L) in the present study, earlier recorded from Car Nicobar Island, India only, indicates the presence of high levels of resistance to sulphadoxine/pyrimethamine in north-east India. Associations between resistant haplotypes and the clinical outcomes and emerging resistance in sulphadoxine/pyrimethamine in relation to the efficacy of the currently used artemisinin combination therapy are discussed.
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Affiliation(s)
| | | | - Anil Prakash
- Regional Medical Research Centre, NE Region (ICMR), Dibrugarh, Assam, India; National Institute for Research in Environmental Health (ICMR), Kamla Nehru Hospital Building, Gandhi Medical College Campus, Bhopal, Madhya Pradesh, India
| | - Khukumoni Bora
- Regional Medical Research Centre, NE Region (ICMR), Dibrugarh, Assam, India
| | - Md Atique Ahmed
- Regional Medical Research Centre, NE Region (ICMR), Dibrugarh, Assam, India
| | - Bibhas Sarma
- Regional Medical Research Centre, NE Region (ICMR), Dibrugarh, Assam, India
| | | | | | - Jagadish Mahanta
- Regional Medical Research Centre, NE Region (ICMR), Dibrugarh, Assam, India
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Ex vivo activity of endoperoxide antimalarials, including artemisone and arterolane, against multidrug-resistant Plasmodium falciparum isolates from Cambodia. Antimicrob Agents Chemother 2014; 58:5831-40. [PMID: 25049252 DOI: 10.1128/aac.02462-14] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Novel synthetic endoperoxides are being evaluated as new components of artemisinin combination therapies (ACTs) to treat artemisinin-resistant Plasmodium falciparum malaria. We conducted blinded ex vivo activity testing of fully synthetic (OZ78 and OZ277) and semisynthetic (artemisone, artemiside, artesunate, and dihydroartemisinin) endoperoxides in the histidine-rich protein 2 enzyme-linked immunosorbent assay against 200 P. falciparum isolates from areas of artemisinin-resistant malaria in western and northern Cambodia in 2009 and 2010. The order of potency and geometric mean (GM) 50% inhibitory concentrations (IC50s) were as follows: artemisone (2.40 nM) > artesunate (8.49 nM) > dihydroartemisinin (11.26 nM) > artemiside (15.28 nM) > OZ277 (31.25 nM) > OZ78 (755.27 nM). Ex vivo activities of test endoperoxides positively correlated with dihydroartemisinin and artesunate. The isolates were over 2-fold less susceptible to dihydroartemisinin than the artemisinin-sensitive P. falciparum W2 clone and showed sensitivity comparable to those with test endoperoxides and artesunate, with isolate/W2 IC50 susceptibility ratios of <2.0. All isolates had P. falciparum chloroquine resistance transporter mutations, with negative correlations in sensitivity to endoperoxides and chloroquine. The activities of endoperoxides (artesunate, dihydroartemisinin, OZ277, and artemisone) significantly correlated with that of the ACT partner drug, mefloquine. Isolates had mutations associated with clinical resistance to mefloquine, with 35% prevalence of P. falciparum multidrug resistance gene 1 (pfmdr1) amplification and 84.5% occurrence of the pfmdr1 Y184F mutation. GM IC50s for mefloquine, lumefantrine, and endoperoxides (artesunate, dihydroartemisinin, OZ277, OZ78, and artemisone) correlated with pfmdr1 copy number. Given that current ACTs are failing potentially from reduced sensitivity to artemisinins and partner drugs, newly identified mutations associated with artemisinin resistance reported in the literature and pfmdr1 mutations should be examined for their combined contributions to emerging ACT resistance.
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Chandramohanadas R, Basappa, Russell B, Liew K, Yau YH, Chong A, Liu M, Gunalan K, Raman R, Renia L, Nosten F, Shochat SG, Dao M, Sasisekharan R, Suresh S, Preiser P. Small molecule targeting malaria merozoite surface protein-1 (MSP-1) prevents host invasion of divergent plasmodial species. J Infect Dis 2014; 210:1616-26. [PMID: 24864124 DOI: 10.1093/infdis/jiu296] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Malaria causes nearly 1 million deaths annually. Recent emergence of multidrug resistance highlights the need to develop novel therapeutic interventions against human malaria. Given the involvement of sugar binding plasmodial proteins in host invasion, we set out to identify such proteins as targets of small glycans. Combining multidisciplinary approaches, we report the discovery of a small molecule inhibitor, NIC, capable of inhibiting host invasion through interacting with a major invasion-related protein, merozoite surface protein-1 (MSP-1). This interaction was validated through computational, biochemical, and biophysical tools. Importantly, treatment with NIC prevented host invasion by Plasmodium falciparum and Plasmodium vivax--major causative organisms of human malaria. MSP-1, an indispensable antigen critical for invasion and suitably localized in abundance on the merozoite surface represents an ideal target for antimalarial development. The ability to target merozoite invasion proteins with specific small inhibitors opens up a new avenue to target this important pathogen.
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Affiliation(s)
- Rajesh Chandramohanadas
- Interdisciplinary Research Group of Infectious Diseases, Singapore MIT Alliance for Research and Technology Centre (SMART) Singapore University of Technology and Design, 20 Dover Drive
| | - Basappa
- Interdisciplinary Research Group of Infectious Diseases, Singapore MIT Alliance for Research and Technology Centre (SMART)
| | - Bruce Russell
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore and
| | - Kingsley Liew
- Interdisciplinary Research Group of Infectious Diseases, Singapore MIT Alliance for Research and Technology Centre (SMART)
| | - Yin Hoe Yau
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Alvin Chong
- Interdisciplinary Research Group of Infectious Diseases, Singapore MIT Alliance for Research and Technology Centre (SMART)
| | - Min Liu
- Interdisciplinary Research Group of Infectious Diseases, Singapore MIT Alliance for Research and Technology Centre (SMART)
| | | | - Rahul Raman
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Laurent Renia
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR)
| | - Francois Nosten
- Shoklo Malaria Research Unit, Mae Sot, Thailand Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, United Kingdom
| | | | - Ming Dao
- Interdisciplinary Research Group of Infectious Diseases, Singapore MIT Alliance for Research and Technology Centre (SMART) Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge
| | - Ram Sasisekharan
- Interdisciplinary Research Group of Infectious Diseases, Singapore MIT Alliance for Research and Technology Centre (SMART) Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Subra Suresh
- Department of Biomedical Engineering and Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh
| | - Peter Preiser
- Interdisciplinary Research Group of Infectious Diseases, Singapore MIT Alliance for Research and Technology Centre (SMART) School of Biological Sciences, Nanyang Technological University, Singapore
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Pollitt LC, Huijben S, Sim DG, Salathé RM, Jones MJ, Read AF. Rapid response to selection, competitive release and increased transmission potential of artesunate-selected Plasmodium chabaudi malaria parasites. PLoS Pathog 2014; 10:e1004019. [PMID: 24763470 PMCID: PMC3999151 DOI: 10.1371/journal.ppat.1004019] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 02/06/2014] [Indexed: 11/19/2022] Open
Abstract
The evolution of drug resistance, a key challenge for our ability to treat and control infections, depends on two processes: de-novo resistance mutations, and the selection for and spread of resistant mutants within a population. Understanding the factors influencing the rates of these two processes is essential for maximizing the useful lifespan of drugs and, therefore, effective disease control. For malaria parasites, artemisinin-based drugs are the frontline weapons in the fight against disease, but reports from the field of slower parasite clearance rates during drug treatment are generating concern that the useful lifespan of these drugs may be limited. Whether slower clearance rates represent true resistance, and how this provides a selective advantage for parasites is uncertain. Here, we show that Plasmodium chabaudi malaria parasites selected for resistance to artesunate (an artemisinin derivative) through a step-wise increase in drug dose evolved slower clearance rates extremely rapidly. In single infections, these slower clearance rates, similar to those seen in the field, provided fitness advantages to the parasite through increased overall density, recrudescence after treatment and increased transmission potential. In mixed infections, removal of susceptible parasites by drug treatment led to substantial increases in the densities and transmission potential of resistant parasites (competitive release). Our results demonstrate the double-edged sword for resistance management: in our initial selection experiments, no parasites survived aggressive chemotherapy, but after selection, the fitness advantage for resistant parasites was greatest at high drug doses. Aggressive treatment of mixed infections resulted in resistant parasites dominating the pool of gametocytes, without providing additional health benefits to hosts. Slower clearance rates can evolve rapidly and can provide a strong fitness advantage during drug treatment in both single and mixed strain infections.
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Affiliation(s)
- Laura C. Pollitt
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
- Centre for Immunology, Infection and Evolution, The University of Edinburgh, Edinburgh, United Kingdom
- * E-mail:
| | - Silvie Huijben
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Derek G. Sim
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Rahel M. Salathé
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Matthew J. Jones
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Andrew F. Read
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
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Paracheck® rapid diagnostic test for detecting malaria infection in under five children: a population-based survey in Burkina Faso. Malar J 2014; 13:101. [PMID: 24636636 PMCID: PMC3995324 DOI: 10.1186/1475-2875-13-101] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 02/17/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Over the past ten years, Rapid Diagnostic Tests (RDT) played a major role in improving the use of biological malaria diagnosis, in particular in poor-resources settings. In Burkina Faso, a recent Demography and Health Survey (DHS) gave the opportunity to assess the performance of the Paracheck® test in under five children nationwide at community level. METHODS A national representative sample of 14,947 households was selected using a stratified two-stage cluster sampling. In one out of two households, all under five children were eligible to be tested for malaria using both RDT and microscopy diagnosis. Paracheck® performance was assessed using miscroscopy as the gold standard. Sensitivity and specificity were calculated as well as the diagnosis accuracy (DA) and the Youden index. RESULTS The malaria infection prevalence was estimated at 66% (95% CI: 64.8-67.2) according to microscopy and at 76.2% (95% CI: 75.1-77.3) according to Paracheck®. The sensitivity and specificity were estimated at 89.9% (95% CI: 89.0-90.8) and 50.4% (95% CI: 48.3-52.6) respectively with a Diagnosis Accuracy of 77% and a Youden index of 40%. The positive predictive value for malaria infection was 77.9% (95% CI: 76.7-79.1) and the negative predictive value was 72.1% (95% CI: 69.7-74.3). Variations were found by age group, period of the year and urban and rural areas, as well as across the 13 regions of the country. CONCLUSION While the sensitivity of the Paracheck® test was high, its specificity was poor in the general under five population of Burkina Faso. These results suggest that Paracheck® is not suitable to assess malaria infection prevalence at community level in areas with high malaria transmission. In such settings, malaria prevalence in the general population could be estimated using microscopy.
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Singh C, Verma VP, Hassam M, Singh AS, Naikade NK, Puri SK. New Orally Active Amino- and Hydroxy-Functionalized 11-Azaartemisinins and Their Derivatives with High Order of Antimalarial Activity against Multidrug-Resistant Plasmodium yoelii in Swiss Mice1. J Med Chem 2014; 57:2489-97. [DOI: 10.1021/jm401774f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chandan Singh
- Division of Medicinal and Process Chemistry and ‡Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226001, India
| | - Ved Prakash Verma
- Division of Medicinal and Process Chemistry and ‡Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226001, India
| | - Mohammad Hassam
- Division of Medicinal and Process Chemistry and ‡Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226001, India
| | - Ajit Shankar Singh
- Division of Medicinal and Process Chemistry and ‡Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226001, India
| | - Niraj K. Naikade
- Division of Medicinal and Process Chemistry and ‡Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226001, India
| | - Sunil K. Puri
- Division of Medicinal and Process Chemistry and ‡Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226001, India
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Nyasembe VO, Tchouassi DP, Kirwa HK, Foster WA, Teal PEA, Borgemeister C, Torto B. Development and assessment of plant-based synthetic odor baits for surveillance and control of malaria vectors. PLoS One 2014; 9:e89818. [PMID: 24587059 PMCID: PMC3933673 DOI: 10.1371/journal.pone.0089818] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 01/26/2014] [Indexed: 11/22/2022] Open
Abstract
Background Recent malaria vector control measures have considerably reduced indoor biting mosquito populations. However, reducing the outdoor biting populations remains a challenge because of the unavailability of appropriate lures to achieve this. This study sought to test the efficacy of plant-based synthetic odor baits in trapping outdoor populations of malaria vectors. Methodology and Principal Finding Three plant-based lures ((E)-linalool oxide [LO], (E)-linalool oxide and (E)-β-ocimene [LO + OC], and a six-component blend comprising (E)-linalool oxide, (E)-β-ocimene, hexanal, β-pinene, limonene, and (E)-β-farnesene [Blend C]), were tested alongside an animal/human-based synthetic lure (comprising heptanal, octanal, nonanal, and decanal [Blend F]) and worn socks in a malaria endemic zone in the western part of Kenya. Mosquito Magnet-X (MM-X) and lightless Centre for Disease Control (CDC) light traps were used. Odor-baited traps were compared with traps baited with either solvent alone or solvent + carbon dioxide (controls) for 18 days in a series of randomized incomplete-block designs of days × sites × treatments. The interactive effect of plant and animal/human odor was also tested by combining LO with either Blend F or worn socks. Our results show that irrespective of trap type, traps baited with synthetic plant odors compared favorably to the same traps baited with synthetic animal odors and worn socks in trapping malaria vectors, relative to the controls. Combining LO and worn socks enhanced trap captures of Anopheles species while LO + Blend F recorded reduced trap capture. Carbon dioxide enhanced total trap capture of both plant- and animal/human-derived odors. However, significantly higher proportions of male and engorged female Anopheles gambiae s.l. were caught when the odor treatments did not include carbon dioxide. Conclusion and Significance The results highlight the potential of plant-based odors and specifically linalool oxide, with or without carbon dioxide, for surveillance and mass trapping of malaria vectors.
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Affiliation(s)
- Vincent O. Nyasembe
- Behavioral and Chemical Ecology Department, International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - David P. Tchouassi
- Behavioral and Chemical Ecology Department, International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Hillary K. Kirwa
- Behavioral and Chemical Ecology Department, International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Woodbridge A. Foster
- Department of Ecology and Organismal Biology, The Ohio State University, Columbus, Ohio, United States of America
| | - Peter E. A. Teal
- Center for Medical, Agricultural, and Veterinary Entomology, U.S. Department of Agriculture, Agricultural Research Service, Gainesville, Florida, United States of America
| | - Christian Borgemeister
- Behavioral and Chemical Ecology Department, International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Center for Development Research, University of Bonn, Bonn, Germany
| | - Baldwyn Torto
- Behavioral and Chemical Ecology Department, International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- * E-mail:
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50
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Modeling malaria infection and immunity against variant surface antigens in Príncipe Island, West Africa. PLoS One 2014; 9:e88110. [PMID: 24520349 PMCID: PMC3919732 DOI: 10.1371/journal.pone.0088110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 01/07/2014] [Indexed: 11/21/2022] Open
Abstract
After remarkable success of vector control campaigns worldwide, concerns about loss of immunity against Plasmodium falciparum due to lack of exposure to the parasite are relevant since an increase of severe cases in less immune individuals is expected. We present a mathematical model to investigate the impact of reducing exposure to the parasite on the immune repertoire against P. falciparum erythrocyte membrane protein 1 (PfEMP1) variants. The model was parameterized with data from Príncipe Island, West Africa, and applied to simulate two alternative transmission scenarios: one where control measures are continued to eventually drive the system to elimination; and another where the effort is interrupted after 6 years of its initiation and the system returns to the initial transmission potential. Population dynamics of parasite prevalence predict that in a few years infection levels return to the pre-control values, while the re-acquisition of the immune repertoire against PfEMP1 is slower, creating a window for increased severity. The model illustrates the consequences of loss of immune repertoire against PfEMP1 in a given setting and can be applied to other regions where similar data may be available.
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