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Risk of hemolysis in Plasmodium vivax malaria patients receiving standard primaquine treatment in a population with high prevalence of G6PD deficiency. Infection 2023; 51:213-222. [PMID: 35976559 PMCID: PMC9892342 DOI: 10.1007/s15010-022-01905-9] [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: 02/11/2022] [Accepted: 08/07/2022] [Indexed: 02/04/2023]
Abstract
BACKGROUND Primaquine is essential for the radical cure of Plasmodium vivax malaria, but it poses a potential danger of severe hemolysis in G6PD-deficient (G6PDd) patients. This study aimed to determine whether primaquine is safe in a population with high G6PD prevalence but lacking G6PD diagnosis capacity. METHODS In Myanmar, 152 vivax patients were gender- and age-matched at 1:3 for G6PDd versus G6PD-normal (G6PDn). Their risk of acute hemolysis was followed for 28 days after treatment with the standard chloroquine and 14-day primaquine (0.25 mg/kg/day) regimen. RESULTS Patients anemic and non-anemic at enrollment showed a rising and declining trend in the mean hemoglobin level, respectively. In males, the G6PDd group showed substantially larger magnitudes of hemoglobin reduction and lower hemoglobin nadir levels than the G6PDn group, but this trend was not evident in females. Almost 1/3 of the patients experienced clinically concerning declines in hemoglobin, with five requiring blood transfusion. CONCLUSIONS The standard 14-day primaquine regimen carries a significant risk of acute hemolytic anemia (AHA) in vivax patients without G6PD testing in a population with a high prevalence of G6PD deficiency and anemia. G6PD testing would avoid most of the clinically significant Hb reductions and AHA in male patients.
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2
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Botnar A, Lawrence G, Maher SP, Vantaux A, Witkowski B, Shiau JC, Merino EF, De Vore D, Yang C, Murray C, Cassera MB, Leahy JW, Kyle DE. Alkyne modified purines for assessment of activation of Plasmodium vivax hypnozoites and growth of pre-erythrocytic and erythrocytic stages in Plasmodium spp. Int J Parasitol 2022; 52:733-744. [PMID: 35447149 PMCID: PMC9576819 DOI: 10.1016/j.ijpara.2022.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 03/28/2022] [Accepted: 03/28/2022] [Indexed: 12/26/2022]
Abstract
Malaria is a major global health problem which predominantly afflicts developing countries. Although many antimalarial therapies are currently available, the protozoan parasite causing this disease, Plasmodium spp., continues to evade eradication efforts. One biological phenomenon hampering eradication efforts is the parasite's ability to arrest development, transform into a drug-insensitive form, and then resume growth post-therapy. Currently, the mechanisms by which the parasite enters arrested development, or dormancy, and later recrudesces or reactivates to continue development, are unknown and the malaria field lacks techniques to study these elusive mechanisms. Since Plasmodium spp. salvage purines for DNA synthesis, we hypothesised that alkyne-containing purine nucleosides could be used to develop a DNA synthesis marker which could be used to investigate mechanisms behind dormancy. Using copper-catalysed click chemistry methods, we observe incorporation of alkyne modified adenosine, inosine, and hypoxanthine in actively replicating asexual blood stages of Plasmodium falciparum and incorporation of modified adenosine in actively replicating liver stage schizonts of Plasmodium vivax. Notably, these modified purines were not incorporated in dormant liver stage hypnozoites, suggesting this marker could be used as a tool to differentiate replicating and non-replicating liver forms and, more broadly, as a tool for advancing our understanding of Plasmodium dormancy mechanisms.
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Affiliation(s)
- Alona Botnar
- Department of Infectious Diseases, University of Georgia, Athens, GA, United States; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Grant Lawrence
- Department of Chemistry, University of South Florida, Tampa, FL, United States
| | - Steven P Maher
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Amélie Vantaux
- Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Benoît Witkowski
- Malaria Molecular Epidemiology Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Justine C Shiau
- Department of Infectious Diseases, University of Georgia, Athens, GA, United States; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Emilio F Merino
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States; Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - David De Vore
- Department of Chemistry, University of South Florida, Tampa, FL, United States
| | - Christian Yang
- Department of Chemistry, University of South Florida, Tampa, FL, United States
| | - Cameron Murray
- Department of Chemistry, University of South Florida, Tampa, FL, United States
| | - Maria B Cassera
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States; Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - James W Leahy
- Department of Chemistry, University of South Florida, Tampa, FL, United States; The Florida Center for Excellence for Drug Discovery and Innovation, University of South Florida, Tampa, GA, United States; Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, GA, United States
| | - Dennis E Kyle
- Department of Infectious Diseases, University of Georgia, Athens, GA, United States; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States; Department of Cellular Biology, University of Georgia, Athens, GA, United States.
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3
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Ketema T, Bacha K, Getahun K, Bassat Q. In vivo efficacy of anti-malarial drugs against clinical Plasmodium vivax malaria in Ethiopia: a systematic review and meta-analysis. Malar J 2021; 20:483. [PMID: 34952581 PMCID: PMC8709955 DOI: 10.1186/s12936-021-04016-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 12/08/2021] [Indexed: 11/30/2022] Open
Abstract
Background Ethiopia is one of the few countries in Africa where Plasmodium vivax commonly co-exists with Plasmodium falciparum, and which accounts for ~ 40% of the total number of malaria infections in the country. Regardless of the growing evidence over many decades of decreasing sensitivity of this parasite to different anti-malarial drugs, there has been no comprehensive attempt made to systematically review and meta-analyse the efficacy of different anti-malarial drugs against P. vivax in the country. However, outlining the efficacy of available anti-malarial drugs against this parasite is essential to guide recommendations for the optimal therapeutic strategy to use in clinical practice. The aim of this study was to synthesize evidence on the efficacy of anti-malarial drugs against clinical P. vivax malaria in Ethiopia. Methods All potentially relevant, peer-reviewed articles accessible in PubMed, Scopus, Web of Science, and Clinical Trial.gov electronic databases were retrieved using a search strategy combining keywords and related database-specific subject terms. Randomized controlled trials (RCTs) and non-randomized trials aiming to investigate the efficacy of anti-malarial drugs against P. vivax were included in the review. Data were analysed using Review Manager Software. Cochrane Q (χ2) and the I2 tests were used to assess heterogeneity. The funnel plot and Egger’s test were used to examine risk of publication bias. Results Out of 1294 identified citations, 14 articles that presented data on 29 treatment options were included in the analysis. These studies enrolled 2144 clinical vivax malaria patients. The pooled estimate of in vivo efficacy of anti-malarial drugs against vivax malaria in Ethiopia was 97.91% (95% CI: 97.29–98.52%), with significant heterogeneity (I2 = 86%, p < 0.0001) and publication bias (Egger’s test = -12.86, p < 0.001). Different anti-malarial drugs showed varied efficacies against vivax malaria. The duration of follow-up significantly affected the calculated efficacy of any given anti-malarial drug, with longer duration of the follow-up (42 days) associated with significantly lower efficacy than efficacy reported on day 28. Also, pooled PCR-corrected efficacy and efficacy estimated from altitudinally lower transmission settings were significantly higher than PCR-uncorrected efficacy that estimated for moderate transmission settings, respectively. Conclusion The overall efficacy of anti-malarial drugs evaluated for the treatment of vivax malaria in Ethiopia was generally high, although there was wide-ranging degree of efficacy, which was affected by the treatment options, duration of follow-up, transmission intensity, and the confirmation procedures for recurrent parasitaemia. Regardless of evidence of sporadic efficacy reduction reported in the country, chloroquine (CQ), the first-line regimen in Ethiopia, remained highly efficacious, supporting its continuous utilization for confirmed P. vivax mono-infections. The addition of primaquine (PQ) to CQ is recommended, as this is the only approved way to provide radical cure, and thus ensure sustained efficacy and longer protection against P. vivax. Continuous surveillance of the efficacy of anti-malarial drugs and clinical trials to allow robust conclusions remains necessary to proactively act against possible emergence and spread of drug-resistant P. vivax in Ethiopia. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-04016-2.
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Affiliation(s)
- Tsige Ketema
- Department of Biology, College of Natural Sciences, Jimma University, Jimma, Ethiopia. .,ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.
| | - Ketema Bacha
- Department of Biology, College of Natural Sciences, Jimma University, Jimma, Ethiopia
| | - Kefelegn Getahun
- Department of Geography and Environmental Studies, College of Social Sciences and Humanity, Jimma University, Jimma, Ethiopia
| | - Quique Bassat
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Catalan Institution for Research and Advanced Studies, ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain.,Centro de Investigação Em Saúde de Manhiça (CISM), Maputo, Mozambique.,Pediatrics Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Esplugues, Barcelona, Spain.,Consorcio de Investigación Biomédica en Red de Epidemiología Y Salud Pública (CIBERESP), Madrid, Spain
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4
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Commons RJ, McCarthy JS, Price RN. Tafenoquine for the radical cure and prevention of malaria: the importance of testing for G6PD deficiency. Med J Aust 2020; 212:152-153.e1. [PMID: 32036613 PMCID: PMC7064913 DOI: 10.5694/mja2.50474] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Robert J Commons
- Menzies School of Health ResearchDarwinNT
- WorldWide Antimalarial Resistance NetworkDarwinNT
- Ballarat Health ServicesBallaratVIC
| | - James S McCarthy
- QIMR Berghofer Medical Research InstituteBrisbaneQLD
- University of QueenslandBrisbaneQLD
| | - Ric N Price
- Menzies School of Health ResearchDarwinNT
- Centre for Tropical Medicine and Global HealthNuffield Department of Clinical MedicineUniversity of OxfordOxfordUK
- Mahidol UniversityBangkokThailand
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First report of glucose-6-phosphate dehydrogenase (G6PD) variants (Mahidol and Acores) from malaria-endemic regions of northeast India and their functional evaluations in-silico. Acta Trop 2020; 202:105252. [PMID: 31678235 DOI: 10.1016/j.actatropica.2019.105252] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 10/29/2019] [Accepted: 10/30/2019] [Indexed: 02/07/2023]
Abstract
G6PD deficiency results from numerous mutations in the G6PD gene and can cause alterations in enzyme function up to varying degrees. P. vivax malaria infections require G6PD deficiency screening because of the potential risk of haemolysis by the gametocytocidal drug (primaquine) during the radical treatment. The present study investigated the incidence of G6PD deficiency from northeast India and further, molecular characterization was performed. During 2014-16, a total of 1,015 patients from four north-eastern states of India (Tripura, Mizoram, Meghalaya & Arunachal Pradesh), were screened for G6PD deficiency, using Beutler's fluorescence spot test (FST) and confirmed with SPAN G6PD kit. The deficient individuals (55/1015, 5.4%) were further characterized by PCR-RFLP and DNA sequencing except one case of lost to follow up. As observed by FST, the frequency of G6PD deficient males (42/538, 7.8%) were found to be higher than females (13/477, 2.73%), (p < 0.0001). Two non-synonymous mutations; G6PD-D (Mahidol)487A (48/54, 88.9%; 36 hemizygous males, 8 homozygous and 4 heterozygous females) and G6PD-D (Acores)595T (2/54, 3.7%) were identified. Remaining (4/54, 7.4%) individuals could not be characterized. Molecular modeling and dynamic simulations were performed for the G6PD wild-type (G6PD-WT) enzyme and its variants. The in-silico results demonstrated alterations in the secondary structures & crucial loss of ligand-protein interactions, which might result in reduced enzyme function, leading to enzyme deficiency. To the best of our knowledge, this is the first report to document G6PD-Mahidol and G6PD-Acores variants from malaria-endemic regions of northeast India, and provided molecular insights on the varied genetic makeup of the studied population.
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Abstract
The technical genesis and practice of 8-aminoquinoline therapy of latent malaria offer singular scientific, clinical, and public health insights. The 8-aminoquinolines brought revolutionary scientific discoveries, dogmatic practices, benign neglect, and, finally, enduring promise against endemic malaria. The clinical use of plasmochin-the first rationally synthesized blood schizontocide and the first gametocytocide, tissue schizontocide, and hypnozoitocide of any kind-commenced in 1926. Plasmochin became known to sometimes provoke fatal hemolytic crises. World War II delivered a newer 8-aminoquinoline, primaquine, and the discovery of glucose-6-phosphate dehydrogenase (G6PD) deficiency as the basis of its hemolytic toxicity came in 1956. Primaquine nonetheless became the sole therapeutic option against latent malaria. After 40 years of fitful development, in 2018 the U.S. Food and Drug Administration registered the 8-aminoquinoline called tafenoquine for the prevention of all malarias and the treatment of those that relapse. Tafenoquine also cannot be used in G6PD-unknown or -deficient patients. The hemolytic toxicity of the 8-aminoquinolines impedes their great potential, but this problem has not been a research priority. This review explores the complex technical dimensions of the history of 8-aminoquinolines. The therapeutic principles thus examined may be leveraged in improved practice and in understanding the bright prospect of discovery of newer drugs that cannot harm G6PD-deficient patients.
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Affiliation(s)
- J Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Eijkman Institute for Molecular Biology, Jakarta, Indonesia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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7
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Commons RJ, Simpson JA, Thriemer K, Hossain MS, Douglas NM, Humphreys GS, Sibley CH, Guerin PJ, Price RN. Risk of Plasmodium vivax parasitaemia after Plasmodium falciparum infection: a systematic review and meta-analysis. THE LANCET. INFECTIOUS DISEASES 2019; 19:91-101. [PMID: 30587297 PMCID: PMC6300482 DOI: 10.1016/s1473-3099(18)30596-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 09/11/2018] [Accepted: 09/13/2018] [Indexed: 01/12/2023]
Abstract
BACKGROUND A 14-day course of primaquine is used for radical cure of Plasmodium vivax and Plasmodium ovale malaria only. We quantified the risk of P vivax parasitaemia after treatment of Plasmodium falciparum with commonly used antimalarial drugs to assess the potential benefits of radical cure for all patients with uncomplicated malaria in co-endemic regions. METHODS In this systematic review and meta-analysis, we searched MEDLINE, Embase, Web of Science, and the Cochrane Database of Systematic Reviews for prospective clinical studies in any language, published between Jan 1, 1960, and Jan 5, 2018, assessing drug efficacy in patients with uncomplicated P falciparum malaria in countries co-endemic for P vivax. Studies were included if the presence or absence of P vivax parasitaemia was recorded after treatment. The primary outcome was the risk of P vivax parasitaemia between day 7 and day 42 after initiation of antimalarial treatment for P falciparum, with the pooled risk calculated by random-effects meta-analysis. We compared the risk of P vivax parasitaemia after treatment with different artemisinin-based combination therapies (ACTs). This study is registered with PROSPERO, number CRD42017064838. FINDINGS 153 of 891 screened studies were included in the analysis, including 31 262 patients from 323 site-specific treatment groups: 130 (85%) studies were from the Asia-Pacific region, 16 (10%) from the Americas, and seven (5%) from Africa. The risk of P vivax parasitaemia by day 42 was 5·6% (95% CI 4·0-7·4; I2=92·0%; 117 estimates). The risk of P vivax parasitaemia was 6·5% (95% CI 4·6-8·6) in regions of short relapse periodicity compared with 1·9% (0·4-4·0) in regions of long periodicity, and was greater after treatment with a more rapidly eliminated ACT: 15·3% (5·1-29·3) for artemether-lumefantrine compared with 4·5% (1·2-9·3) for dihydroartemisinin-piperaquine and 5·2% (2·9-7·9) for artesunate-mefloquine. Recurrent parasitaemia was delayed in patients treated with ACTs containing mefloquine or piperaquine compared with artemether-lumefantrine, but by day 63 the risk of vivax parasitaemia was more than 15% for all ACTs assessed. INTERPRETATION Our findings show a high risk of vivax parasitaemia after treatment of falciparum malaria, particularly in areas with short relapse periodicity and after rapidly eliminated treatment. In co-endemic regions, universal radical cure for all patients with uncomplicated malaria has the potential to substantially reduce recurrent malaria. FUNDING Australian National Health and Medical Research Council, Royal Australasian College of Physicians, Wellcome Trust, and Bill & Melinda Gates Foundation.
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Affiliation(s)
- Robert J Commons
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia; WorldWide Antimalarial Resistance Network, Oxford, UK.
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC, Australia
| | - Kamala Thriemer
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Mohammad S Hossain
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia; WorldWide Antimalarial Resistance Network, Oxford, UK; Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC, Australia; International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Nicholas M Douglas
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia; Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC, Australia
| | - Georgina S Humphreys
- WorldWide Antimalarial Resistance Network, Oxford, UK; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Carol H Sibley
- WorldWide Antimalarial Resistance Network, Oxford, UK; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK; Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Philippe J Guerin
- WorldWide Antimalarial Resistance Network, Oxford, UK; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Ric N Price
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia; WorldWide Antimalarial Resistance Network, Oxford, UK; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
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8
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Randomized, Double-Blind, Placebo-Controlled Studies to Assess Safety and Prophylactic Efficacy of Naphthoquine-Azithromycin Combination for Malaria Prophylaxis in Southeast Asia. Antimicrob Agents Chemother 2018; 62:AAC.00793-18. [PMID: 29987144 DOI: 10.1128/aac.00793-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 07/05/2018] [Indexed: 01/01/2023] Open
Abstract
New prophylactic drugs against malaria infections are urgently needed. We conducted randomized, double-blind, placebo-controlled, phase 2 trials of a new antimalarial drug combination, naphthoquine-azithromycin (NQAZ), to determine its safety and protective efficacy in a low-endemicity area of Southeast Asia. In the first trial, 127 healthy volunteers were randomized to receive two single doses of either 400 mg of NQAZ (200 mg of each drug), 800 mg of NQAZ (400 mg of each drug), or placebo on day 0 and day 30. Weekly follow-ups were performed for 2 months, and physical and clinical laboratory exams were done during the second and eighth week. Both drug regimens were well tolerated, without any serious adverse events. Four adverse events (transient and slight elevations of serum transaminase concentrations) were found only in the two drug-treated groups and thus might be drug-related. In the second trial, 353 volunteer villagers were randomized into the same three groups as in the first trial, and malaria infections were followed for a month. For the intention-to-treat analysis, both regimens offered greater than 90% prophylactic efficacies against all malaria infections. When the analysis was done according to parasite species, 400 mg and 800 mg NQAZ provided 81.63 and 90.59% prophylactic efficacies, respectively, against Plasmodium falciparum infections, whereas both offered 100% prophylactic efficacy against Plasmodium vivax and Plasmodium ovale These trials showed that NQAZ had a good safety profile, and monthly single doses of 400 mg or 800 mg for adults offered excellent prophylaxis against malaria infections, especially the two relapsing species.
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Mugheirbi NA, O’Connell P, Serrano DR, Healy AM, Taylor LS, Tajber L. A Comparative Study on the Performance of Inert and Functionalized Spheres Coated with Solid Dispersions Made of Two Structurally Related Antifungal Drugs. Mol Pharm 2017; 14:3718-3728. [DOI: 10.1021/acs.molpharmaceut.7b00482] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Naila A. Mugheirbi
- School
of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, College Green, Dublin 2, Ireland
- Department
of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Peter O’Connell
- School
of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, College Green, Dublin 2, Ireland
| | - Dolores R. Serrano
- School
of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, College Green, Dublin 2, Ireland
| | - Anne Marie Healy
- School
of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, College Green, Dublin 2, Ireland
| | - Lynne S. Taylor
- Department
of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Lidia Tajber
- School
of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, College Green, Dublin 2, Ireland
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10
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Abstract
Malaria remains a serious clinical and public health problem, the object of an ongoing technological and humanitarian struggle to abate the very substantial harm done. The manner by which humanity approached malaria control changed abruptly and profoundly after 1945 with the advent of the insecticide DDT. Malariologists in the first half of the twentieth century conceived precise modifications to natural or man-made environments aimed at making those less hospitable to specific anopheline mosquito vector species. This practical malariology achieved very significant reductions in burdens of morbidity and mortality, but the revolutionary insecticide eliminated the need for its specialized knowledge and diverse practices. By 1970 mosquito resistance to DDT and perceived environmental concerns precipitated the collapse of what had been a vigorous global campaign to eradicate malaria. Humanity did not then revitalize practical malariology but turned to another commodity as the foundation of control strategy, the war-spurred suite of synthetic antimalarial drugs developed in the 1940s and 1950s. When those drugs became lost to parasite resistance in the latter twentieth century, malaria resurged globally. Since 2005, tens of billions of dollars mobilized new commodities to control malaria: point-of-care diagnostics, effective artemisinin-based treatments, and longer-lasting insecticide treated bed nets. The know-how of practical malariology is not part of that ongoing commodities-based strategy. This article examines contemporary malaria control in the broad strokes of a strategy mitigating the consequences of infection contrasted to that of the abandoned practical malariology strategy of prevention. The inherent risks and limitations of over-reliance upon commodities in striving to control malaria may prompt consideration of a strategic posture inclusive of the proven methods of practical malariology.
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Affiliation(s)
- J Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Jalan Diponegoro No.69, Jakarta, 10430, Indonesia. .,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
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11
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Howes RE, Chan ER, Rakotomanga TA, Schulte S, Gibson J, Zikursh M, Franchard T, Ramiranirina B, Ratsimbasoa A, Zimmerman PA. Prevalence and genetic variants of G6PD deficiency among two Malagasy populations living in Plasmodium vivax-endemic areas. Malar J 2017; 16:139. [PMID: 28376871 PMCID: PMC5381087 DOI: 10.1186/s12936-017-1771-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/08/2017] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The prevalence and variants of G6PD deficiency in the Plasmodium vivax-endemic zones of Madagascar remain unknown. The admixed African-Austronesian origins of the Malagasy population make it probable that a heterogeneous mix of genetic variants with a spectrum of clinical severity will be circulating. This would have implications for the widespread use of P. vivax radical cure therapy. Two study populations in the P. vivax-endemic western foothills region of Madagascar were selected for G6PD screening. Both the qualitative fluorescent spot test and G6PD genotyping were used to screen all participants. RESULTS A total of 365 unrelated male volunteers from the Tsiroanomandidy, Mandoto, and Miandrivazo districts of Madagascar were screened and 12.9% were found to be phenotypically G6PD deficient. Full gene sequencing of 95 samples identified 16 single nucleotide polymorphisms, which were integrated into a genotyping assay. Genotyping (n = 291) found one individual diagnosed with the severe G6PD Mediterranean C563T mutation, while the remaining G6PD deficient samples had mutations of African origin, G6PD A- and G6PD A. CONCLUSIONS Deployment of P. vivax radical cure in Madagascar must be considerate of the risks presented by the observed prevalence of G6PDd prevalence. The potential morbidity associated with cumulative episodes of P. vivax clinical relapses requires a strategy for increasing access to safe radical cure. The observed dominance of African G6PDd haplotypes is surprising given the known mixed African-Austronesian origins of the Malagasy population; more widespread surveying of G6PDd epidemiology across the island would be required to characterize the distribution of G6PD haplotypes across Madagascar.
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Affiliation(s)
- Rosalind E Howes
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA. .,Nuffield Department of Medicine, Oxford Big Data Institute, University of Oxford, Oxford, UK.
| | - Ernest R Chan
- Institute for Computational Biology, Case Western Reserve University, Cleveland, OH, USA
| | - Tovonahary Angelo Rakotomanga
- National Malaria Control Programme, Ministry of Health, Antananarivo, Madagascar.,Faculty of Science, University of Antananarivo, Antananarivo, Madagascar
| | - Seth Schulte
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
| | - John Gibson
- Institute for Computational Biology, Case Western Reserve University, Cleveland, OH, USA
| | - Melinda Zikursh
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
| | - Thierry Franchard
- National Malaria Control Programme, Ministry of Health, Antananarivo, Madagascar.,Faculty of Science, University of Antananarivo, Antananarivo, Madagascar
| | - Brune Ramiranirina
- National Malaria Control Programme, Ministry of Health, Antananarivo, Madagascar
| | - Arsène Ratsimbasoa
- National Malaria Control Programme, Ministry of Health, Antananarivo, Madagascar.,University of Antananarivo, Antananarivo, Madagascar
| | - Peter A Zimmerman
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA.
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12
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Lin CH, Chen CH, Lin ZC, Fang JY. Recent advances in oral delivery of drugs and bioactive natural products using solid lipid nanoparticles as the carriers. J Food Drug Anal 2017; 25:219-234. [PMID: 28911663 PMCID: PMC9332520 DOI: 10.1016/j.jfda.2017.02.001] [Citation(s) in RCA: 147] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 02/21/2017] [Indexed: 11/30/2022] Open
Abstract
Chemical and enzymatic barriers in the gastrointestinal (GI) tract hamper the oral delivery of many labile drugs. The GI epithelium also contributes to poor permeability for numerous drugs. Drugs with poor aqueous solubility have difficulty dissolving in the GI tract, resulting in low bioavailability. Nanomedicine provides an opportunity to improve the delivery efficiency of orally administered drugs. Solid lipid nanoparticles (SLNs) are categorized as a new generation of lipid nanoparticles consisting of a complete solid lipid matrix. SLNs used for oral administration offer several benefits over conventional formulations, including increased solubility, enhanced stability, improved epithelium permeability and bioavailability, prolonged half-life, tissue targeting, and minimal side effects. The nontoxic excipients and sophisticated material engineering of SLNs tailor the controllable physicochemical properties of the nanoparticles for GI penetration via mucosal or lymphatic transport. In this review, we highlight the recent progress in the development of SLNs for disease treatment. Recent application of oral SLNs includes therapies for cancers, central nervous system-related disorders, cardiovascular-related diseases, infection, diabetes, and osteoporosis. In addition to drugs that may be active cargos in SLNs, some natural compounds with pharmacological activity are also suitable for SLN encapsulation to enhance oral bioavailability. In this article, we systematically introduce the concepts and amelioration mechanisms of the nanomedical techniques for drug- and natural compound-loaded SLNs.
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Milner EE, Berman J, Caridha D, Dickson SP, Hickman M, Lee PJ, Marcsisin SR, Read LT, Roncal N, Vesely BA, Xie LH, Zhang J, Zhang P, Li Q. Cytochrome P450 2D-mediated metabolism is not necessary for tafenoquine and primaquine to eradicate the erythrocytic stages of Plasmodium berghei. Malar J 2016; 15:588. [PMID: 27923405 PMCID: PMC5142148 DOI: 10.1186/s12936-016-1632-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 11/22/2016] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Due to the ability of the 8-aminoquinolines (8AQs) to kill different stages of the malaria parasite, primaquine (PQ) and tafenoquine (TQ) are vital for causal prophylaxis and the eradication of erythrocytic Plasmodium sp. parasites. Recognizing the potential role of cytochrome (CYP) 450 2D6 in the metabolism and subsequent hepatic efficacy of 8-aminoquinolines, studies were designed to explore whether CYP2D-mediated metabolism was related to the ability of single-dose PQ and TQ to eliminate the asexual and sexual erythrocytic stages of Plasmodium berghei. METHODS An IV P. berghei sporozoite murine challenge model was utilized to directly compare causal prophylactic and erythrocytic activity (asexual and sexual parasite stages) dose-response relationships in C57BL/6 wild-type (WT) mice and subsequently compare the erythrocytic activity of PQ and TQ in WT and CYP2D knock-out (KO) mice. RESULTS Single-dose administration of either 25 mg/kg TQ or 40 mg/kg PQ eradicated the erythrocytic stages (asexual and sexual) of P. berghei in C57BL WT and CYP2D KO mice. In WT animals, the apparent elimination of hepatic infections occurs at lower doses of PQ than are required to eliminate erythrocytic infections. In contrast, the minimally effective dose of TQ needed to achieve causal prophylaxis and to eradicate erythrocytic parasites was analogous. CONCLUSION The genetic deletion of the CYP2D cluster does not affect the ability of PQ or TQ to eradicate the blood stages (asexual and sexual) of P. berghei after single-dose administration.
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Affiliation(s)
- Erin E Milner
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA.
| | - Jonathan Berman
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Diana Caridha
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Samuel P Dickson
- United States Army Medical Materiel Development Authority (USAMMDA), Ft Detrick, Frederick, MD, USA
| | - Mark Hickman
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Patricia J Lee
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Sean R Marcsisin
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Lisa T Read
- United States Army Medical Materiel Development Authority (USAMMDA), Ft Detrick, Frederick, MD, USA
| | - Norma Roncal
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Brian A Vesely
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Lisa H Xie
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Jing Zhang
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Ping Zhang
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Qigui Li
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
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Vizzi E, Bastidas G, Hidalgo M, Colman L, Pérez HA. Prevalence and molecular characterization of G6PD deficiency in two Plasmodium vivax endemic areas in Venezuela: predominance of the African A-(202A/376G) variant. Malar J 2016; 15:19. [PMID: 26753754 PMCID: PMC4710037 DOI: 10.1186/s12936-015-1069-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 12/22/2015] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Glucose-6-phosphate dehydrogenase (G6PD) deficiency causes acute haemolytic anaemia triggered by oxidative drugs such as primaquine (PQ), used for Plasmodium vivax malaria radical cure. However, in many endemic areas of vivax malaria, patients are treated with PQ without any evaluation of their G6PD status. METHODS G6PD deficiency and its genetic heterogeneity were evaluated in northeastern and southeastern areas from Venezuela, Cajigal (Sucre state) and Sifontes (Bolívar state) municipalities, respectively. Blood samples from 664 randomly recruited unrelated individuals were screened for G6PD activity by a quantitative method. Mutation analysis for exons 4-8 of G6PD gen was performed on DNA isolated from G6PD-deficient (G6PDd) subjects through PCR-RFLP and direct DNA sequencing. RESULTS Quantitative biochemical characterization revealed that overall 24 (3.6%) subjects were G6PDd (average G6PD enzyme activity 4.5 ± 1.2 U/g Hb, moderately deficient, class III), while DNA analysis showed one or two mutated alleles in 19 of them (79.2%). The G6PD A-(202A/376G) variant was the only detected in 17 (70.8%) individuals, 13 of them hemizygous males and four heterozygous females. Two males carried only the 376A → G mutation. No other mutation was found in the analysed exons. CONCLUSIONS The G6PDd prevalence was as low as that one shown by nearby countries. This study contributes to the knowledge of the genetic background of Venezuelan population, especially of those living in malaria-endemic areas. Despite the high degree of genetic mixing described for Venezuelan population, a net predominance of the mild African G6PD A-(202A/376G) variant was observed among G6PDd subjects, suggesting a significant flow of G6PD genes from Africa to Americas, almost certainly introduced through African and/or Spanish immigrants during and after the colonization. The data suggest that 1:27 individuals of the studied population could be G6PDd and therefore at risk of haemolysis under precipitating factors. Information about PQ effect on G6PDd individuals carrying mild variant is limited, but since the regimen of 45 mg weekly dose for prevention of malaria relapse does not seem to be causing clinically significant haemolysis in people having the G6PD A-variant, a reasoned weighing of risk-benefit for its use in Venezuela should be done, when implementing public health strategies of control and elimination.
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Affiliation(s)
- Esmeralda Vizzi
- Laboratorio de Biología de Virus, Centro de Microbiología y Biología Celular, Instituto Venezolano de Investigaciones Científicas, Apdo 21827, Caracas, 1020-A, Venezuela.
| | - Gilberto Bastidas
- Laboratorio de Biología de Virus, Centro de Microbiología y Biología Celular, Instituto Venezolano de Investigaciones Científicas, Apdo 21827, Caracas, 1020-A, Venezuela.
- Laboratorio de Inmunoparasitología, Centro de Microbiología y Biología Celular, Instituto Venezolano de Investigaciones Científicas, Apdo 21827, Caracas, 1020-A, Venezuela.
- Departamento de Salud Pública, Facultad de Ciencias de la Salud, Universidad de Carabobo, Valencia, Edo. Carabobo, Venezuela.
| | - Mariana Hidalgo
- Laboratorio de Inmunoparasitología, Centro de Microbiología y Biología Celular, Instituto Venezolano de Investigaciones Científicas, Apdo 21827, Caracas, 1020-A, Venezuela.
| | - Laura Colman
- Laboratorio de Inmunoparasitología, Centro de Microbiología y Biología Celular, Instituto Venezolano de Investigaciones Científicas, Apdo 21827, Caracas, 1020-A, Venezuela.
| | - Hilda A Pérez
- Laboratorio de Inmunoparasitología, Centro de Microbiología y Biología Celular, Instituto Venezolano de Investigaciones Científicas, Apdo 21827, Caracas, 1020-A, Venezuela.
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Tanner M, Greenwood B, Whitty CJM, Ansah EK, Price RN, Dondorp AM, von Seidlein L, Baird JK, Beeson JG, Fowkes FJI, Hemingway J, Marsh K, Osier F. Malaria eradication and elimination: views on how to translate a vision into reality. BMC Med 2015; 13:167. [PMID: 26208740 PMCID: PMC4514994 DOI: 10.1186/s12916-015-0384-6] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Although global efforts in the past decade have halved the number of deaths due to malaria, there are still an estimated 219 million cases of malaria a year, causing more than half a million deaths. In this forum article, we asked experts working in malaria research and control to discuss the ways in which malaria might eventually be eradicated. Their collective views highlight the challenges and opportunities, and explain how multi-factorial and integrated processes could eventually make malaria eradication a reality.
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Affiliation(s)
- Marcel Tanner
- Swiss Tropical & Public Health Institute, 4002, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Brian Greenwood
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
| | - Christopher J M Whitty
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
| | - Evelyn K Ansah
- Research and Development Division, Ghana Health Service, Accra, Ghana.
| | - Ric N Price
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia. .,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| | - Arjen M Dondorp
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK. .,Mahidol Oxford Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Lorenz von Seidlein
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK. .,Mahidol Oxford Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - J Kevin Baird
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK. .,Eijkman-Oxford Clinical Research Unit, Jalan Diponegoro No.69, Jakarta, 10430, Indonesia.
| | - James G Beeson
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Department of Microbiology, Monash University, 19 Innovation Walk, Victoria, 3800, Australia.
| | - Freya J I Fowkes
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia. .,Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia. .,Department of Infectious Diseases, Monash University, Melbourne, Australia.
| | - Janet Hemingway
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Kevin Marsh
- African Academy of Sciences, Miotoni Road, Miotoni Lane, House No. 8 Karen, P.O. Box 24916-00502, Nairobi, Kenya.
| | - Faith Osier
- KEMRI Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.
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16
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Zhang L, Yang Y, Liu R, Li Q, Yang F, Ma L, Liu H, Chen X, Yang Z, Cui L, He Y. A multiplex method for detection of glucose-6-phosphate dehydrogenase (G6PD) gene mutations. Int J Lab Hematol 2015; 37:739-45. [PMID: 26190099 DOI: 10.1111/ijlh.12405] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 06/05/2015] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect caused by G6PD gene mutations. This study aimed to develop a cost-effective, multiplex, genotyping method for detecting common mutations in the G6PD gene. METHODS We used a SNaPshot approach to genotype multiple G6PD mutations that are common to human populations in South-East Asia. This assay is based on multiplex PCR coupled with primer extension reactions. Different G6PD gene mutations were determined by peak retention time and colors of the primer extension products. RESULTS We designed PCR primers for multiplex amplification of the G6PD gene fragments and for primer extension reactions to genotype 11 G6PD mutations. DNA samples from a total of 120 unrelated G6PD-deficient individuals from the China-Myanmar border area were used to establish and validate this method. Direct sequencing of the PCR products demonstrated 100% concordance between the SNaPshot and the sequencing results. CONCLUSION The SNaPshot method offers a specific and sensitive alternative for simultaneously interrogating multiple G6PD mutations.
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Affiliation(s)
- L Zhang
- Department of Cell Biology and Medical Genetics, Kunming Medical University, Kunming, Yunnan Province, China
| | - Y Yang
- Department of Cell Biology and Medical Genetics, Kunming Medical University, Kunming, Yunnan Province, China
| | - R Liu
- The First Affiliated Hospital, Kunming Medical University, Kunming, Yunnan Province, China
| | - Q Li
- Department of Cell Biology and Medical Genetics, Kunming Medical University, Kunming, Yunnan Province, China
| | - F Yang
- Department of Cell Biology and Medical Genetics, Kunming Medical University, Kunming, Yunnan Province, China
| | - L Ma
- Department of Histology and Embryology, Kunming Medical University, Kunming, Yunnan Province, China
| | - H Liu
- The First Affiliated Hospital, Kunming Medical University, Kunming, Yunnan Province, China
| | - X Chen
- Kunming City Maternal and Child Health Hospital, Kunming, Yunnan Province, China
| | - Z Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province, China
| | - L Cui
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Y He
- Department of Cell Biology and Medical Genetics, Kunming Medical University, Kunming, Yunnan Province, China
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Tekwani BL, Avula B, Sahu R, Chaurasiya ND, Khan SI, Jain S, Fasinu PS, Herath HMTB, Stanford D, Nanayakkara NPD, McChesney JD, Yates TW, ElSohly MA, Khan IA, Walker LA. Enantioselective pharmacokinetics of primaquine in healthy human volunteers. Drug Metab Dispos 2015; 43:571-7. [PMID: 25637634 DOI: 10.1124/dmd.114.061127] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Primaquine (PQ), a racemic drug, is the only treatment available for radical cure of relapsing Plasmodium vivax malaria and blocking transmission of P. falciparum malaria. Recent studies have shown differential pharmacologic and toxicologic profiles of individual PQ enantiomers in rodent, dog, and primate animal models. This study was conducted in six healthy adult human volunteers to determine the plasma pharmacokinetic profile of enantiomers of PQ and carboxyprimaquine (cPQ), the major plasma metabolite. The individuals were orally administered PQ diphosphate, equivalent to 45-mg base, 30 minutes after a normal breakfast. Blood samples were collected at different time intervals, and plasma samples were analyzed for enantiomers of PQ and cPQ. Plasma PQ concentrations were low and variable for both parent enantiomers and peaked around 2-4 hours. Peak (-)-(R)-PQ concentrations ranged from 121 ng/ml to 221 ng/ml, and peak (+)-(S)-PQ concentrations ranged from 168 ng/ml to 299 ng/ml. The cPQ concentrations were much higher and were surprisingly consistent from subject to subject. Essentially all the cPQ detected in plasma was (-)-cPQ. The peak concentrations of (-)-cPQ were observed at 8 hours (range: 1104-1756 ng/ml); however, very high concentrations were sustained through 24 hours. (+)-cPQ was two orders of magnitude lower than (-)-cPQ, and in a few subjects it was detected but only under the limit of quantification. In vitro studies with primary human hepatocytes also suggested more rapid metabolism of (-)-PQ compared with (+)-PQ. The results suggest more rapid metabolism of (-)-PQ to (-) cPQ compared with (+)-PQ. Alternatively, (+)-PQ or (+)-cPQ could be rapidly converted to another metabolite(s) or distributed to tissues. This is the first clinical report on enantioselective pharmacokinetic profiles of PQ and cPQ and supports further clinical evaluation of individual PQ enantiomers.
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Affiliation(s)
- Babu L Tekwani
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Bharathi Avula
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Rajnish Sahu
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Narayan D Chaurasiya
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Shabana I Khan
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Surendra Jain
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Pius S Fasinu
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - H M T Bandara Herath
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Donald Stanford
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - N P Dhammika Nanayakkara
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - James D McChesney
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Travis W Yates
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Mahmoud A ElSohly
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Ikhlas A Khan
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
| | - Larry A Walker
- National Center for Natural Products Research (B.L.T., B.A., R.S., N.D.C., S.I.K., S.J., P.S.F., H.M.T.B.H., D.S., N.P.D.N., M.A.E., I.A.K., L.A.W.), Departments of BioMolecular Sciences (B.L.T., S.I.K., S.J., I.A.K., L.A.W.) and Pharmaceutics (M.A.E.), School of Pharmacy, and Department of Student Health Services (T.W.Y.), University of Mississippi, University; Ironstone Separations, Inc., Etta (J.D.M.); ElSohly Laboratories, Inc., Oxford (M.A.E.), Mississippi
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Lauinger IL, Vivas L, Perozzo R, Stairiker C, Tarun A, Zloh M, Zhang X, Xu H, Tonge PJ, Franzblau SG, Pham DH, Esguerra CV, Crawford AD, Maes L, Tasdemir D. Potential of lichen secondary metabolites against Plasmodium liver stage parasites with FAS-II as the potential target. JOURNAL OF NATURAL PRODUCTS 2013; 76:1064-70. [PMID: 23806111 PMCID: PMC4119598 DOI: 10.1021/np400083k] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Chemicals targeting the liver stage (LS) of the malaria parasite are useful for causal prophylaxis of malaria. In this study, four lichen metabolites, evernic acid (1), vulpic acid (2), psoromic acid (3), and (+)-usnic acid (4), were evaluated against LS parasites of Plasmodium berghei. Inhibition of P. falciparum blood stage (BS) parasites was also assessed to determine stage specificity. Compound 4 displayed the highest LS activity and stage specificity (LS IC50 value 2.3 μM, BS IC50 value 47.3 μM). The compounds 1-3 inhibited one or more enzymes (PfFabI, PfFabG, and PfFabZ) from the plasmodial fatty acid biosynthesis (FAS-II) pathway, a potential drug target for LS activity. To determine species specificity and to clarify the mechanism of reported antibacterial effects, 1-4 were also evaluated against FabI homologues and whole cells of various pathogens (S. aureus, E. coli, M. tuberculosis). Molecular modeling studies suggest that lichen acids act indirectly via binding to allosteric sites on the protein surface of the FAS-II enzymes. Potential toxicity of compounds was assessed in human hepatocyte and cancer cells (in vitro) as well as in a zebrafish model (in vivo). This study indicates the therapeutic and prophylactic potential of lichen metabolites as antibacterial and antiplasmodial agents.
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Affiliation(s)
- Ina L. Lauinger
- Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University of London, London WC1N 1AX, UK
| | - Livia Vivas
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Remo Perozzo
- School of Pharmaceutical Sciences, University of Geneva, CH-1211 Geneva 4, Switzerland
| | - Christopher Stairiker
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 152614, USA
| | - Alice Tarun
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 152614, USA
| | - Mire Zloh
- Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University of London, London WC1N 1AX, UK
| | - Xujie Zhang
- Institute for Chemical Biology and Drug Discovery, Department of Chemistry, Stony Brook University, NY 11794, USA
| | - Hua Xu
- Institute for Chemical Biology and Drug Discovery, Department of Chemistry, Stony Brook University, NY 11794, USA
| | - Peter J. Tonge
- Institute for Chemical Biology and Drug Discovery, Department of Chemistry, Stony Brook University, NY 11794, USA
| | - Scott G. Franzblau
- Institute for Tuberculosis Research, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Duc-Hung Pham
- Laboratory for Molecular Biodiscovery, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, 3000 Leuven, Belgium
| | - Camila V. Esguerra
- Laboratory for Molecular Biodiscovery, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, 3000 Leuven, Belgium
| | - Alexander D. Crawford
- Laboratory for Molecular Biodiscovery, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, 3000 Leuven, Belgium
| | - Louis Maes
- Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, University of Antwerp, 2610 Antwerp, Belgium
| | - Deniz Tasdemir
- Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University of London, London WC1N 1AX, UK
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Kaisar MMM, Supali T, Wiria AE, Hamid F, Wammes LJ, Sartono E, Luty AJF, Brienen EAT, Yazdanbakhsh M, van Lieshout L, Verweij JJ. Epidemiology of Plasmodium infections in Flores Island, Indonesia using real-time PCR. Malar J 2013; 12:169. [PMID: 23706132 PMCID: PMC3679745 DOI: 10.1186/1475-2875-12-169] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 05/16/2013] [Indexed: 02/06/2023] Open
Abstract
Background DNA-based diagnostic methods have been shown to be highly sensitive and specific for the detection of malaria. An 18S-rRNA-based, real-time polymerase chain reaction (PCR) was used to determine the prevalence and intensity of Plasmodium infections on Flores Island, Indonesia. Methods Microscopy and real-time multiplex PCR for the detection of Plasmodium species was performed on blood samples collected in a population-based study in Nangapanda Flores Island, Indonesia. Results A total 1,509 blood samples were analysed. Real-time PCR revealed prevalence for Plasmodium falciparum, Plasmodium vivax, and Plasmodium malariae to be 14.5%, 13.2%, and 1.9% respectively. Sub-microscopic parasitaemia were found in more than 80% of all positive cases. The prevalence of P. falciparum and P. vivax was significantly higher in subjects younger than 20 years (p ≤ 0.01). In the present study, among non-symptomatic healthy individuals, anaemia was strongly correlated with the prevalence and load of P. falciparum infections (p ≤ 0.01; p = 0.02) and with the load of P. vivax infections (p = 0.01) as detected with real-time PCR. Subjects with AB blood group tend to have a higher risk of being infected with P. falciparum and P. vivax when compared to other blood groups. Conclusion The present study has shown that real-time PCR provides more insight in the epidemiology of Plasmodium infections and can be used as a monitoring tool in the battle against malaria. The unsurpassed sensitivity of real-time PCR reveals that sub microscopic infections are common in this area, which are likely to play an important role in transmission and control. Trial registration Trials number ISRCTN83830814.
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von Seidlein L, Auburn S, Espino F, Shanks D, Cheng Q, McCarthy J, Baird K, Moyes C, Howes R, Ménard D, Bancone G, Winasti-Satyahraha A, Vestergaard LS, Green J, Domingo G, Yeung S, Price R. Review of key knowledge gaps in glucose-6-phosphate dehydrogenase deficiency detection with regard to the safe clinical deployment of 8-aminoquinoline treatment regimens: a workshop report. Malar J 2013; 12:112. [PMID: 23537118 PMCID: PMC3616837 DOI: 10.1186/1475-2875-12-112] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 03/14/2013] [Indexed: 01/24/2023] Open
Abstract
The diagnosis and management of glucose-6-phosphate dehydrogenase (G6PD) deficiency is a crucial aspect in the current phases of malaria control and elimination, which will require the wider use of 8-aminoquinolines for both reducing Plasmodium falciparum transmission and achieving the radical cure of Plasmodium vivax. 8-aminoquinolines, such as primaquine, can induce severe haemolysis in G6PD-deficient individuals, potentially creating significant morbidity and undermining confidence in 8-aminoquinoline prescription. On the other hand, erring on the side of safety and excluding large numbers of people with unconfirmed G6PD deficiency from treatment with 8-aminoquinolines will diminish the impact of these drugs. Estimating the remaining G6PD enzyme activity is the most direct, accessible, and reliable assessment of the phenotype and remains the gold standard for the diagnosis of patients who could be harmed by the administration of primaquine. Genotyping seems an unambiguous technique, but its use is limited by cost and the large range of recognized G6PD genotypes. A number of enzyme activity assays diagnose G6PD deficiency, but they require a cold chain, specialized equipment, and laboratory skills. These assays are impractical for care delivery where most patients with malaria live. Improvements to the diagnosis of G6PD deficiency are required for the broader and safer use of 8-aminoquinolines to kill hypnozoites, while lower doses of primaquine may be safely used to kill gametocytes without testing. The discussions and conclusions of a workshop conducted in Incheon, Korea in May 2012 to review key knowledge gaps in G6PD deficiency are reported here.
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Affiliation(s)
- Lorenz von Seidlein
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia.
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Preiser P, Renia L, Cooke BM. Editorial--Singapore Malaria Network Meeting (SingMalNet) 2012. Int J Parasitol 2012; 42:1047. [PMID: 23164544 DOI: 10.1016/j.ijpara.2012.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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