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Hellingman A, Sifoniou K, Buser T, Thommen BT, Walz A, Passecker A, Collins J, Hupfeld M, Wittlin S, Witmer K, Brancucci NMB. Next Generation Chemiluminescent Probes for Antimalarial Drug Discovery. ACS Infect Dis 2024; 10:1286-1297. [PMID: 38556981 PMCID: PMC11019541 DOI: 10.1021/acsinfecdis.3c00707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 03/07/2024] [Accepted: 03/13/2024] [Indexed: 04/04/2024]
Abstract
Malaria is caused by parasites of the Plasmodium genus and remains one of the most pressing human health problems. The spread of parasites resistant to or partially resistant to single or multiple drugs, including frontline antimalarial artemisinin and its derivatives, poses a serious threat to current and future malaria control efforts. In vitro drug assays are important for identifying new antimalarial compounds and monitoring drug resistance. Due to its robustness and ease of use, the [3H]-hypoxanthine incorporation assay is still considered a gold standard and is widely applied, despite limited sensitivity and the dependence on radioactive material. Here, we present a first-of-its-kind chemiluminescence-based antimalarial drug screening assay. The effect of compounds on P. falciparum is monitored by using a dioxetane-based substrate (AquaSpark β-D-galactoside) that emits high-intensity luminescence upon removal of a protective group (β-D-galactoside) by a transgenic β-galactosidase reporter enzyme. This biosensor enables highly sensitive, robust, and cost-effective detection of asexual, intraerythrocytic P. falciparum parasites without the need for parasite enrichment, washing, or purification steps. We are convinced that the ultralow detection limit of less than 100 parasites of the presented biosensor system will become instrumental in malaria research, including but not limited to drug screening.
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Affiliation(s)
- Angela Hellingman
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- University
of Basel, 4001 Basel, Switzerland
| | - Kleopatra Sifoniou
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- University
of Basel, 4001 Basel, Switzerland
| | - Tamara Buser
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- University
of Basel, 4001 Basel, Switzerland
| | - Basil T. Thommen
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- University
of Basel, 4001 Basel, Switzerland
| | - Annabelle Walz
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- University
of Basel, 4001 Basel, Switzerland
| | - Armin Passecker
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- University
of Basel, 4001 Basel, Switzerland
| | | | | | - Sergio Wittlin
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- University
of Basel, 4001 Basel, Switzerland
| | - Kathrin Witmer
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- University
of Basel, 4001 Basel, Switzerland
- NEMIS
Technologies AG, 8804 Au, ZH, Switzerland
| | - Nicolas M. B. Brancucci
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- University
of Basel, 4001 Basel, Switzerland
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2
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van Heerden A, Turon G, Duran-Frigola M, Pillay N, Birkholtz LM. Machine Learning Approaches Identify Chemical Features for Stage-Specific Antimalarial Compounds. ACS OMEGA 2023; 8:43813-43826. [PMID: 38027377 PMCID: PMC10666252 DOI: 10.1021/acsomega.3c05664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 10/18/2023] [Accepted: 10/20/2023] [Indexed: 12/01/2023]
Abstract
Efficacy data from diverse chemical libraries, screened against the various stages of the malaria parasite Plasmodium falciparum, including asexual blood stage (ABS) parasites and transmissible gametocytes, serve as a valuable reservoir of information on the chemical space of compounds that are either active (or not) against the parasite. We postulated that this data can be mined to define chemical features associated with the sole ABS activity and/or those that provide additional life cycle activity profiles like gametocytocidal activity. Additionally, this information could provide chemical features associated with inactive compounds, which could eliminate any future unnecessary screening of similar chemical analogs. Therefore, we aimed to use machine learning to identify the chemical space associated with stage-specific antimalarial activity. We collected data from various chemical libraries that were screened against the asexual (126 374 compounds) and sexual (gametocyte) stages of the parasite (93 941 compounds), calculated the compounds' molecular fingerprints, and trained machine learning models to recognize stage-specific active and inactive compounds. We were able to build several models that predict compound activity against ABS and dual activity against ABS and gametocytes, with Support Vector Machines (SVM) showing superior abilities with high recall (90 and 66%) and low false-positive predictions (15 and 1%). This allowed the identification of chemical features enriched in active and inactive populations, an important outcome that could be mined for essential chemical features to streamline hit-to-lead optimization strategies of antimalarial candidates. The predictive capabilities of the models held true in diverse chemical spaces, indicating that the ML models are therefore robust and can serve as a prioritization tool to drive and guide phenotypic screening and medicinal chemistry programs.
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Affiliation(s)
- Ashleigh van Heerden
- Department
of Biochemistry, Genetics and Microbiology, Institute for Sustainable
Malaria Control, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Gemma Turon
- Ersilia
Open Source Initiative, 28 Belgrave Road, Cambridge CB1 3DE, U.K.
| | | | - Nelishia Pillay
- Department
of Computer Science, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Lyn-Marié Birkholtz
- Department
of Biochemistry, Genetics and Microbiology, Institute for Sustainable
Malaria Control, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
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3
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Lima C, Verdaguer IB, Wunderlich G, Katzin AM, Crabb BS, Gilson PR, Azevedo MF. Conditional expression of NanoLuc luciferase through a multimodular system offers rapid detection of antimalarial drug activity. Exp Parasitol 2023; 254:108620. [PMID: 37716462 DOI: 10.1016/j.exppara.2023.108620] [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: 04/28/2023] [Revised: 09/06/2023] [Accepted: 09/12/2023] [Indexed: 09/18/2023]
Abstract
Conditional gene expression is a powerful tool to investigate putative vaccine and drug targets, especially in a haploid organism such as Plasmodium falciparum. Inducible systems based on regulation of either transcription, translation, protein or mRNA stability, among others, allow switching on an off the expression of any desired gene causing specific gain or loss of function phenotypes. However, those systems can be cumbersome involving the construction of large plasmids and generation of multiple transgenic parasite lines. In addition, the dynamic range of regulation achieved is not predictable for each individual gene and can be insufficient to generate detectable phenotypes when the genes of interest are silenced. Here, we combined up to three distinct inducible systems to regulate the expression of a single gene. Expression of the reporter NanoLuc luciferase was regulated over 40-fold, which correlates to the regulation achieved by each individual system multiplied by each other. We applied the conditionally expressed NanoLuc to evaluate the effect of fast-acting antimalarials such as chloroquine and artesunate as well as of slower-acting ones such as atovaquone. The conditionally expressed reporter allowed faster and more reliable detection of toxicity to the parasite, which correlated to the expected action of each compound. Bioluminescence achieved by the expression of this inducible highly sensitive reporter is therefore a promising tool to investigate the temporal effect of potential new antimalarials. This single plasmid combination system might also prove useful to achieve sufficient regulation of genes of interest to produce loss-of-function phenotypes.
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Affiliation(s)
- Caroline Lima
- Federal University of Sao Paulo, Santos, Sao Paulo, Brazil
| | - Ignasi B Verdaguer
- Departamento de Parasitologia, Instituto de Ciência Biomédicas, Universidade de São Paulo, Avenida Prof. Lineu Prestes, 1374, São Paulo, SP, 05508-900, Brazil
| | - Gerhard Wunderlich
- Departamento de Parasitologia, Instituto de Ciência Biomédicas, Universidade de São Paulo, Avenida Prof. Lineu Prestes, 1374, São Paulo, SP, 05508-900, Brazil
| | - Alejandro M Katzin
- Departamento de Parasitologia, Instituto de Ciência Biomédicas, Universidade de São Paulo, Avenida Prof. Lineu Prestes, 1374, São Paulo, SP, 05508-900, Brazil
| | - Brendan S Crabb
- Burnet Institute, Melbourne, VIC, 3004, Australia; University of Melbourne, VIC, 3052, Australia; Monash University, Melbourne, VIC, 3004, Australia
| | - Paul R Gilson
- Burnet Institute, Melbourne, VIC, 3004, Australia; University of Melbourne, VIC, 3052, Australia
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Rosenthal MR, Ng CL. High-content imaging as a tool to quantify and characterize malaria parasites. CELL REPORTS METHODS 2023; 3:100516. [PMID: 37533635 PMCID: PMC10391350 DOI: 10.1016/j.crmeth.2023.100516] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 01/18/2023] [Accepted: 06/02/2023] [Indexed: 08/04/2023]
Abstract
In 2021, Plasmodium falciparum was responsible for 619,000 reported malaria-related deaths. Resistance has been detected to every clinically used antimalarial, urging the development of novel antimalarials with uncompromised mechanisms of actions. High-content imaging allows researchers to collect and quantify numerous phenotypic properties at the single-cell level, and machine learning-based approaches enable automated classification and clustering of cell populations. By combining these technologies, we developed a method capable of robustly differentiating and quantifying P. falciparum asexual blood stages. These phenotypic properties also allow for the quantification of changes in parasite morphology. Here, we demonstrate that our analysis can be used to quantify schizont nuclei, a phenotype that previously had to be enumerated manually. By monitoring stage progression and quantifying parasite phenotypes, our method can discern stage specificity of new compounds, thus providing insight into the compound's mode of action.
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Affiliation(s)
- Melissa R. Rosenthal
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Caroline L. Ng
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Global Center for Health Security, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Biology, University of Omaha, Omaha, NE 68182, USA
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Miyazaki Y, Vos MW, Geurten FJA, Bigeard P, Kroeze H, Yoshioka S, Arisawa M, Inaoka DK, Soulard V, Dechering KJ, Franke-Fayard B, Miyazaki S. A versatile Plasmodium falciparum reporter line expressing NanoLuc enables highly sensitive multi-stage drug assays. Commun Biol 2023; 6:713. [PMID: 37438491 DOI: 10.1038/s42003-023-05078-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 06/27/2023] [Indexed: 07/14/2023] Open
Abstract
Transgenic luciferase-expressing Plasmodium falciparum parasites have been widely used for the evaluation of anti-malarial compounds. Here, to screen for anti-malarial drugs effective against multiple stages of the parasite, we generate a P. falciparum reporter parasite that constitutively expresses NanoLuciferase (NanoLuc) throughout its whole life cycle. The NanoLuc-expressing P. falciparum reporter parasite shows a quantitative NanoLuc signal in the asexual blood, gametocyte, mosquito, and liver stages. We also establish assay systems to evaluate the anti-malarial activity of compounds at the asexual blood, gametocyte, and liver stages, and then determine the 50% inhibitory concentration (IC50) value of several anti-malarial compounds. Through the development of this robust high-throughput screening system, we identify an anti-malarial compound that kills the asexual blood stage parasites. Our study highlights the utility of the NanoLuc reporter line, which may advance anti-malarial drug development through the improved screening of compounds targeting the human malarial parasite at multiple stages.
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Affiliation(s)
- Yukiko Miyazaki
- Department of Molecular Infection Dynamics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 852-8523, Nagasaki, Japan.
- Department of Parasitology, Leiden University Medical Center, 2333 ZA, Leiden, The Netherlands.
- Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
| | - Martijn W Vos
- TropIQ Health Sciences, Transistorweg 5, 6534 AT, Nijmegen, The Netherlands
| | - Fiona J A Geurten
- Department of Parasitology, Leiden University Medical Center, 2333 ZA, Leiden, The Netherlands
| | - Pierre Bigeard
- Sorbonne Université, Inserm, CNRS, Centre d'Immunologie et des Maladies Infectieuses, CIMI-Paris, F-75013, Paris, France
| | - Hans Kroeze
- Department of Parasitology, Leiden University Medical Center, 2333 ZA, Leiden, The Netherlands
| | - Shohei Yoshioka
- Graduate School of Pharmaceutical Sciences, Osaka University, 565-0871, Osaka, Japan
| | - Mitsuhiro Arisawa
- Graduate School of Pharmaceutical Sciences, Osaka University, 565-0871, Osaka, Japan
| | - Daniel Ken Inaoka
- Department of Molecular Infection Dynamics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 852-8523, Nagasaki, Japan
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, 852-8523, Japan
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Valerie Soulard
- Sorbonne Université, Inserm, CNRS, Centre d'Immunologie et des Maladies Infectieuses, CIMI-Paris, F-75013, Paris, France
| | - Koen J Dechering
- TropIQ Health Sciences, Transistorweg 5, 6534 AT, Nijmegen, The Netherlands
| | - Blandine Franke-Fayard
- Department of Parasitology, Leiden University Medical Center, 2333 ZA, Leiden, The Netherlands
| | - Shinya Miyazaki
- Department of Parasitology, Leiden University Medical Center, 2333 ZA, Leiden, The Netherlands.
- Department of Cellular Architecture Studies, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 852-8523, Nagasaki, Japan.
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Barnes CBG, Dans MG, Jonsdottir TK, Crabb BS, Gilson PR. PfATP4 inhibitors in the Medicines for Malaria Venture Malaria Box and Pathogen Box block the schizont-to-ring transition by inhibiting egress rather than invasion. Front Cell Infect Microbiol 2022; 12:1060202. [PMID: 36530423 PMCID: PMC9747762 DOI: 10.3389/fcimb.2022.1060202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 11/15/2022] [Indexed: 12/05/2022] Open
Abstract
The cation efflux pump Plasmodium falciparum ATPase 4 (PfATP4) maintains Na+ homeostasis in malaria parasites and has been implicated in the mechanism of action of many structurally diverse antimalarial agents, including >7% of the antimalarial compounds in the Medicines for Malaria Venture's 'Malaria Box' and 'Pathogen Box'. Recent screens of the 'Malaria Box' and 'Pathogen Box' revealed that many PfATP4 inhibitors prevent parasites from exiting their host red blood cell (egress) or entering new host cells (invasion), suggesting that these compounds may have additional molecular targets involved in egress or invasion. Here, we demonstrate that five PfATP4 inhibitors reduce egress but not invasion. These compounds appear to inhibit egress by blocking the activation of protein kinase G, an enzyme that, once stimulated, rapidly activates parasite egress. We establish a direct link between egress and PfATP4 function by showing that the inhibition of egress is attenuated in a Na+-depleted environment and in parasites with a mutation in pfatp4. Finally, we show that PfATP4 inhibitors induce host cell lysis when administered prior to the completion of parasite replication. Since host cell lysis mimics egress but is not followed by invasion, this phenomenon likely explains why several PfATP4 inhibitors were previously classified as invasion inhibitors. Collectively, our results confirm that PfATP4-mediated Na+ efflux is critical to the regulation of parasite egress.
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Affiliation(s)
- Claudia B. G. Barnes
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,Department of Medicine, The University of Melbourne, Melbourne, VIC, Australia
| | - Madeline G. Dans
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,School of Medicine, Deakin University, Geelong, VIC, Australia
| | - Thorey K. Jonsdottir
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,Department of Immunology and Pathology, Monash University, Melbourne, VIC, Australia
| | - Brendan S. Crabb
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,Department of Microbiology and Immunology, The University of Melbourne, Parkville, VIC, Australia,Department of Immunology and Pathology, Monash University, Melbourne, VIC, Australia
| | - Paul R. Gilson
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,Department of Microbiology and Immunology, The University of Melbourne, Parkville, VIC, Australia,*Correspondence: Paul R. Gilson,
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Pomun T, Wonginta P, Kubera A. Malaria Box Compounds against Anopheles gambiae (Diptera: Culicidae) Carboxypeptidase B Activity to Block Malaria Transmission. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:1355-1362. [PMID: 35522203 DOI: 10.1093/jme/tjac043] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Indexed: 06/14/2023]
Abstract
Carboxypeptidase B (CPB) plays an important role in blood digestion in mosquitos, aiding the release of free amino acids. Anopheles CPB is a target to block malaria transmission because it facilitates Plasmodium invasion of the mosquito midgut. Our study aimed to discover inhibitors of Anopheles CPB to prevent Plasmodium development in the mosquito. The Anopheles gambiae cpb (Agcpb) gene without a signal sequence was cloned into the pET28b expression vector. The recombinant AgCPB protein was expressed in E. coli BL21(DE3) within inclusion bodies after induction with 0.5 mM isopropyl β-D-1-thiogalactopyranoside at 37°C for 4 h. The protein pellet was dissolved in 6 M urea, purified by affinity chromatography, and dialyzed in reaction buffer. The refolded recombinant AgCPB could digest the hippuryl-arginine substrate similarly to that of the commercial porcine pancreas CPB. The 20 top-scoring malaria box compounds from the virtual-screening results were then chosen for an in vitro inhibition assay against AgCPB. Four of the 20 malaria box compounds could inhibit AgCPB activity. The compound MMV007591 was the most potent inhibitor with an IC50 at 0.066 µM. The results indicate that these candidate compounds may be utilized in drug development against mosquito CPB activity to curb malaria transmission.
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Affiliation(s)
- Tippawan Pomun
- Department of Genetics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand
| | - Phattaradanai Wonginta
- Department of Genetics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand
| | - Anchanee Kubera
- Department of Genetics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand
- Centre for Advanced Studies in Tropical Natural Resources, Kasetsart University, Bangkok 10900, Thailand
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8
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Reader J, van der Watt ME, Birkholtz LM. Streamlined and Robust Stage-Specific Profiling of Gametocytocidal Compounds Against Plasmodium falciparum. Front Cell Infect Microbiol 2022; 12:926460. [PMID: 35846744 PMCID: PMC9282888 DOI: 10.3389/fcimb.2022.926460] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 05/30/2022] [Indexed: 12/29/2022] Open
Abstract
Malaria elimination is dependent on the ability to target both the pathogenic and transmissible stages of the human malaria parasite, Plasmodium falciparum. These forms of the parasite are differentiated by unique developmental stages, each with their own biological mechanisms and processes. These individual stages therefore also respond differently to inhibitory compounds, and this complicates the discovery of multistage active antimalarial agents. The search for compounds with transmission-blocking activity has focused on screening for activity on mature gametocytes, with only limited descriptions available for the activity of such compounds on immature stage gametocytes. This therefore poses a gap in the profiling of antimalarial agents for pan-reactive, multistage activity to antimalarial leads. Here, we optimized an effective and robust strategy for the simple and cost-effective description of the stage-specific action of gametocytocidal antimalarial compounds.
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Affiliation(s)
- Janette Reader
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Mariette E. van der Watt
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Institute for Sustainable Malaria Control, School of Health Systems and Public Health, University of Pretoria, Pretoria, South Africa
| | - Lyn-Marié Birkholtz
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- *Correspondence: Lyn-Marié Birkholtz,
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Carey MA, Medlock GL, Stolarczyk M, Petri WA, Guler JL, Papin JA. Comparative analyses of parasites with a comprehensive database of genome-scale metabolic models. PLoS Comput Biol 2022; 18:e1009870. [PMID: 35196325 PMCID: PMC8901074 DOI: 10.1371/journal.pcbi.1009870] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 03/07/2022] [Accepted: 01/27/2022] [Indexed: 01/01/2023] Open
Abstract
Protozoan parasites cause diverse diseases with large global impacts. Research on the pathogenesis and biology of these organisms is limited by economic and experimental constraints. Accordingly, studies of one parasite are frequently extrapolated to infer knowledge about another parasite, across and within genera. Model in vitro or in vivo systems are frequently used to enhance experimental manipulability, but these systems generally use species related to, yet distinct from, the clinically relevant causal pathogen. Characterization of functional differences among parasite species is confined to post hoc or single target studies, limiting the utility of this extrapolation approach. To address this challenge and to accelerate parasitology research broadly, we present a functional comparative analysis of 192 genomes, representing every high-quality, publicly-available protozoan parasite genome including Plasmodium, Toxoplasma, Cryptosporidium, Entamoeba, Trypanosoma, Leishmania, Giardia, and other species. We generated an automated metabolic network reconstruction pipeline optimized for eukaryotic organisms. These metabolic network reconstructions serve as biochemical knowledgebases for each parasite, enabling qualitative and quantitative comparisons of metabolic behavior across parasites. We identified putative differences in gene essentiality and pathway utilization to facilitate the comparison of experimental findings and discovered that phylogeny is not the sole predictor of metabolic similarity. This knowledgebase represents the largest collection of genome-scale metabolic models for both pathogens and eukaryotes; with this resource, we can predict species-specific functions, contextualize experimental results, and optimize selection of experimental systems for fastidious species.
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Affiliation(s)
- Maureen A. Carey
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
- * E-mail: (MAC); (JP)
| | - Gregory L. Medlock
- Department of Biomedical Engineering, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Michał Stolarczyk
- Department of Biology, University of Virginia, Charlottesville, Virginia, United States of America
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - William A. Petri
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Jennifer L. Guler
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
- Department of Biology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Jason A. Papin
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
- Department of Biomedical Engineering, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
- Department of Biochemistry & Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
- * E-mail: (MAC); (JP)
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10
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Birkholtz LM, Alano P, Leroy D. Transmission-blocking drugs for malaria elimination. Trends Parasitol 2022; 38:390-403. [DOI: 10.1016/j.pt.2022.01.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 01/19/2022] [Accepted: 01/24/2022] [Indexed: 12/24/2022]
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11
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Mourot L, Schmitt M, Mouray E, Spichty M, Florent I, Albrecht S. Structure-activity relationship and molecular modelling studies of quinazolinedione derivatives MMV665916 as potential antimalarial agent. Bioorg Med Chem 2021; 51:116513. [PMID: 34798379 DOI: 10.1016/j.bmc.2021.116513] [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: 06/23/2021] [Revised: 10/11/2021] [Accepted: 10/17/2021] [Indexed: 10/19/2022]
Abstract
A series of new quinazolinedione derivatives have been readily synthesized and evaluated for their in vitro antiplasmodial growth inhibition activity. Most of the compounds inhibited P. falciparum FcB1 strain in the low to medium micromolar concentration. The 2-ethoxy 8ag', 2-trifluoromethoxy 8ai' and 4-fluoro-2-methoxy 8ak' showed the best inhibitory activity with EC50 values around 5 µM and were non-toxic to the primary human fibroblast cell line AB943. However, these compounds were less potent than the original hit MMV665916, which showed remarkable growth inhibition with EC50 value of 0.4 µM and presented the highest selectivity index (SI > 250). In addition, a novel approach for determining the docking poses of these quinazolinedione derivatives with their potential protein target, the P. falciparum farnesyltransferase PfFT, was investigated.
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Affiliation(s)
- Laura Mourot
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA UMR 7042, F-68000 Mulhouse, France
| | - Marjorie Schmitt
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA UMR 7042, F-68000 Mulhouse, France
| | - Elisabeth Mouray
- Unité Molécules de Communication et Adaptation des Micro-organismes, UMR7245, Muséum National d'Histoire Naturelle, CNRS, Sorbonne Universités, Paris, France
| | - Martin Spichty
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA UMR 7042, F-68000 Mulhouse, France
| | - Isabelle Florent
- Unité Molécules de Communication et Adaptation des Micro-organismes, UMR7245, Muséum National d'Histoire Naturelle, CNRS, Sorbonne Universités, Paris, France
| | - Sébastien Albrecht
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA UMR 7042, F-68000 Mulhouse, France.
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12
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The Novel bis-1,2,4-Triazine MIPS-0004373 Demonstrates Rapid and Potent Activity against All Blood Stages of the Malaria Parasite. Antimicrob Agents Chemother 2021; 65:e0031121. [PMID: 34460304 DOI: 10.1128/aac.00311-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Novel bis-1,2,4-triazine compounds with potent in vitro activity against Plasmodium falciparum parasites were recently identified. The bis-1,2,4-triazines represent a unique antimalarial pharmacophore and are proposed to act by a novel but as-yet-unknown mechanism of action. This study investigated the activity of the bis-1,2,4-triazine MIPS-0004373 across the mammalian life cycle stages of the parasite and profiled the kinetics of activity against blood and transmission stage parasites in vitro and in vivo. MIPS-0004373 demonstrated rapid and potent activity against P. falciparum, with excellent in vitro activity against all asexual blood stages. Prolonged in vitro drug exposure failed to generate stable resistance de novo, suggesting a low propensity for the emergence of resistance. Excellent activity was observed against sexually committed ring stage parasites, but activity against mature gametocytes was limited to inhibiting male gametogenesis. Assessment of liver stage activity demonstrated good activity in an in vitro P. berghei model but no activity against Plasmodium cynomolgi hypnozoites or liver schizonts. The bis-1,2,4-triazine MIPS-0004373 efficiently cleared an established P. berghei infection in vivo, with efficacy similar to that of artesunate and chloroquine and a recrudescence profile comparable to that of chloroquine. This study demonstrates the suitability of bis-1,2,4-triazines for further development toward a novel treatment for acute malaria.
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Hermann T, Hochegger P, Dolensky J, Seebacher W, Saf R, Kaiser M, Mäser P, Weis R. New Acyl Derivatives of 3-Aminofurazanes and Their Antiplasmodial Activities. Pharmaceuticals (Basel) 2021; 14:ph14050412. [PMID: 33925485 PMCID: PMC8145535 DOI: 10.3390/ph14050412] [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: 03/29/2021] [Revised: 04/21/2021] [Accepted: 04/24/2021] [Indexed: 11/16/2022] Open
Abstract
An N-acylated furazan-3-amine of a Medicines for Malaria Venture (MMV) project has shown activity against different strains of Plasmodium falciparum. Seventeen new derivatives were prepared and tested in vitro for their activities against blood stages of two strains of Plasmodium falciparum. Several structure-activity relationships were revealed. The activity strongly depended on the nature of the acyl moiety. Only benzamides showed promising activity. The substitution pattern of their phenyl ring affected the activity and the cytotoxicity of compounds. In addition, physicochemical parameters were calculated (log P, log D, ligand efficiency) or determined experimentally (permeability) via a PAMPA. The N-(4-(3,4-diethoxyphenyl)-1,2,5-oxadiazol-3-yl)-3-(trifluoromethyl)benzamide possessed good physicochemical properties and showed high antiplasmodial activity against a chloroquine-sensitive strain (IC50(NF54) = 0.019 µM) and even higher antiplasmodial activity against a multiresistant strain (IC50(K1) = 0.007 µM). Compared to the MMV compound, the permeability and the activity against the multiresistant strain were improved.
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Affiliation(s)
- Theresa Hermann
- Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstraße 1, A-8010 Graz, Austria; (T.H.); (J.D.); (W.S.); (R.W.)
| | - Patrick Hochegger
- Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstraße 1, A-8010 Graz, Austria; (T.H.); (J.D.); (W.S.); (R.W.)
- Correspondence: ; Tel.: +43-316-380-5379; Fax: +43-316-380-9846
| | - Johanna Dolensky
- Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstraße 1, A-8010 Graz, Austria; (T.H.); (J.D.); (W.S.); (R.W.)
| | - Werner Seebacher
- Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstraße 1, A-8010 Graz, Austria; (T.H.); (J.D.); (W.S.); (R.W.)
| | - Robert Saf
- Institute for Chemistry and Technology of Materials (ICTM), Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria;
| | - Marcel Kaiser
- Swiss Tropical and Public Health Institute, Socinstraße 57, CH-4002 Basel, Switzerland; (M.K.); (P.M.)
| | - Pascal Mäser
- Swiss Tropical and Public Health Institute, Socinstraße 57, CH-4002 Basel, Switzerland; (M.K.); (P.M.)
| | - Robert Weis
- Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstraße 1, A-8010 Graz, Austria; (T.H.); (J.D.); (W.S.); (R.W.)
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Investigation of factors affecting the production of P. falciparum gametocytes in an Indian isolate. 3 Biotech 2021; 11:55. [PMID: 33489674 DOI: 10.1007/s13205-020-02586-7] [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: 10/30/2020] [Accepted: 12/03/2020] [Indexed: 10/22/2022] Open
Abstract
The fundamental requirement of every gametocytocidal drug screening assay is the sufficient numbers of healthy and viable gametocytes. The number of in vitro gametocytes grossly depends on the genetic capacity of parasites to produce gametocytes and on various environmental factors that are not precisely elucidated. In the present study, we tested multiple environmental factors that are reported, hypothesized, or predicted to influence gametocyte numbers. We observed that hypoxanthine and the use of freshly drawn human blood significantly enhance gametocytemia (p < 0.05) in vitro. However, other tested factors did not significantly affect gametocytemia. The addition of N-acetyl glucosamine to the culture enriched the gametocytes but d-sorbitol (5% v/v) in amounts and duration of incubation tested was unable to do so without negatively affecting the maturity and health of the gametocytes. Although the in vitro gametocyte production depends on the genetic capability of the parasite strain tested, various environmental factors also control the ability of the strain to produce gametocytes up to a certain extent. This is the first study testing the role of various environmental factors that might affect the gametocyte development in a gametocyte producing strain. The results presented herein will help in the optimization of gametocyte production procedures for various gametocytocidal drug screening assays.
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Potluri V, Shandil RK, Gavara R, Sambasivam G, Campo B, Wittlin S, Narayanan S. Discovery of FNDR-20123, a histone deacetylase inhibitor for the treatment of Plasmodium falciparum malaria. Malar J 2020; 19:365. [PMID: 33046062 PMCID: PMC7549214 DOI: 10.1186/s12936-020-03421-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 09/20/2020] [Indexed: 12/14/2022] Open
Abstract
Background Emergence of anti-malarial drug resistance and perpetual increase in malaria incidence necessitates the development of novel anti-malarials. Histone deacetylases (HDAC) has been shown to be a promising target for malaria, despite this, there are no HDAC inhibitors in clinical trials for malaria treatment. This can be attributed to the poor pharmacokinetics, bioavailability and selectivity of the HDAC inhibitors. Methods A collection of HDAC inhibitors were screened for anti-malarial activity, and the best candidate was profiled in parasite-killing kinetics, growth inhibition of sensitive and multi-drug resistant (MDR) strains and against gametocytes. Absorption, distribution, metabolism and excretion pharmacokinetics (ADME-PK) parameters of FNDR-20123 were determined, and in vivo efficacy was studied in a mouse model for Plasmodium falciparum infection. Results A compound library of HDAC inhibitors (180 in number) was screened for anti-malarial activity, of which FNDR-20123 was the most potent candidate. The compound had been shown to inhibit Plasmodium HDAC with IC50 of 31 nM and human HDAC with IC50 of 3 nM. The IC50 obtained for P. falciparum in asexual blood-stage assay was 42 nM. When compared to atovaquone and pyrimethamine, the killing profiles of FNDR-20123 were better than atovaquone and comparable to pyrimethamine. The IC50 values for the growth inhibition of sensitive and MDR strains were similar, indicating that there is no cross-resistance and a low risk of resistance development. The selected compound was also active against gametocytes, indicating a potential for transmission control: IC50 values being 190 nM for male and > 5 µM for female gametocytes. FNDR-20123 is a stable candidate in human/mouse/rat liver microsomes (> 75% remaining post 2-h incubation), exhibits low plasma protein binding (57% in humans) with no human Ether-à-go–go-Related Gene (hERG) liability (> 100 µM), and does not inhibit any of the cytochrome P450 (CYP) isoforms tested (IC50 > 25 µM). It also shows negligible cytotoxicity to HepG-2 and THP-1 cell lines. The oral pharmacokinetics in rats at 100 mg/kg body weight shows good exposures (Cmax = 1.1 µM) and half-life (T1/2 = 5.5 h). Furthermore, a 14-day toxicokinetic study at 100 mg/kg daily dose did not show any abnormality in body weight or gross organ pathology. FNDR-20123 is also able to reduce parasitaemia significantly in a mouse model for P. falciparum infection when dosed orally and subcutaneously. Conclusion FNDR-20123 may be a suitable candidate for the treatment of malaria, which can be further developed.
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Affiliation(s)
- Vijay Potluri
- Foundation for Neglected Disease Research, Bengaluru, India
| | | | - R Gavara
- Anthem Biosciences Private Limited, Bengaluru, India
| | | | - Brice Campo
- Medicines for Malaria Venture, Geneva, Switzerland
| | - Sergio Wittlin
- Swiss Tropical and Public Health Institute, Basel, Switzerland
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Jennison C, Lucantoni L, O'Neill MT, McConville R, Erickson SM, Cowman AF, Sleebs BE, Avery VM, Boddey JA. Inhibition of Plasmepsin V Activity Blocks Plasmodium falciparum Gametocytogenesis and Transmission to Mosquitoes. Cell Rep 2020; 29:3796-3806.e4. [PMID: 31851913 DOI: 10.1016/j.celrep.2019.11.073] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 10/14/2019] [Accepted: 11/15/2019] [Indexed: 12/20/2022] Open
Abstract
Plasmodium falciparum gametocytes infect mosquitoes and are responsible for malaria transmission. New interventions that block transmission could accelerate malaria elimination. Gametocytes develop within erythrocytes and activate protein export pathways that remodel the host cell. Plasmepsin V (PMV) is an aspartyl protease that is required for protein export in asexual parasites, but its function and essentiality in gametocytes has not been definitively proven, nor has PMV been assessed as a transmission-blocking drug target. Here, we show that PMV is expressed and can be inhibited specifically in P. falciparum stage I-II gametocytes. PMV inhibitors block processing and export of gametocyte effector proteins and inhibit development of stage II-V gametocytes. Gametocytogenesis in the presence of sublethal inhibitor concentrations results in stage V gametocytes that fail to infect mosquitoes. Therefore, PMV primes gametocyte effectors for export, which is essential for the development and fitness of gametocytes for transmission to mosquitoes.
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Affiliation(s)
- Charlie Jennison
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville 3010, VIC, Australia
| | - Leonardo Lucantoni
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan 4111, QLD, Australia
| | - Matthew T O'Neill
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, VIC, Australia
| | - Robyn McConville
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville 3010, VIC, Australia
| | - Sara M Erickson
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville 3010, VIC, Australia
| | - Alan F Cowman
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville 3010, VIC, Australia
| | - Brad E Sleebs
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville 3010, VIC, Australia
| | - Vicky M Avery
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan 4111, QLD, Australia
| | - Justin A Boddey
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville 3010, VIC, Australia.
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Moyo P, Mugumbate G, Eloff JN, Louw AI, Maharaj VJ, Birkholtz LM. Natural Products: A Potential Source of Malaria Transmission Blocking Drugs? Pharmaceuticals (Basel) 2020; 13:E251. [PMID: 32957668 PMCID: PMC7558993 DOI: 10.3390/ph13090251] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/15/2020] [Accepted: 09/16/2020] [Indexed: 12/17/2022] Open
Abstract
The ability to block human-to-mosquito and mosquito-to-human transmission of Plasmodium parasites is fundamental to accomplish the ambitious goal of malaria elimination. The WHO currently recommends only primaquine as a transmission-blocking drug but its use is severely restricted by toxicity in some populations. New, safe and clinically effective transmission-blocking drugs therefore need to be discovered. While natural products have been extensively investigated for the development of chemotherapeutic antimalarial agents, their potential use as transmission-blocking drugs is comparatively poorly explored. Here, we provide a comprehensive summary of the activities of natural products (and their derivatives) of plant and microbial origins against sexual stages of Plasmodium parasites and the Anopheles mosquito vector. We identify the prevailing challenges and opportunities and suggest how these can be mitigated and/or exploited in an endeavor to expedite transmission-blocking drug discovery efforts from natural products.
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Affiliation(s)
- Phanankosi Moyo
- Malaria Parasite Molecular Laboratory, Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag x20, Hatfield, 0028 Pretoria, South Africa;
| | - Grace Mugumbate
- Department of Chemistry, School of Natural Sciences and Mathematics, Chinhoyi University of Technology, Private Bag, 7724 Chinhoyi, Zimbabwe;
| | - Jacobus N. Eloff
- Phytomedicine Programme, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Private Bag x04, Onderstepoort 0110 Pretoria, South Africa;
| | - Abraham I. Louw
- Malaria Parasite Molecular Laboratory, Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag x20, Hatfield, 0028 Pretoria, South Africa;
| | - Vinesh J. Maharaj
- Department of Chemistry, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag x20, Hatfield, 0028 Pretoria, South Africa;
| | - Lyn-Marié Birkholtz
- Malaria Parasite Molecular Laboratory, Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag x20, Hatfield, 0028 Pretoria, South Africa;
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Dhal AK, Pani A, Yun SI, Mahapatra RK. In-silico analysis of Calcium Dependent Protein Kinase 6 of Cr yptosporidium parvum through molecular modeling, docking, and dynamics simulation study. J Biomol Struct Dyn 2020; 39:5461-5470. [PMID: 32633680 DOI: 10.1080/07391102.2020.1790036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Calcium Dependent Protein Kinases are found in the Apicomplexan, algae, and plants; however, they are not reported in vertebrates and are regarded as excellent drug targets for pharmaceutical interventions. Calcium Dependent Protein Kinases of Cryptosporidium are probably involved in the regulation of invasion and egress process during the infection of the host cells. The previous study reported that after the Calcium Dependent Protein Kinase 1 gene, Calcium Dependent Protein Kinase 6 of Cryptosporidium parvum is expressed in all stages of the parasite (merozoites/schizonts as well as sexual stages) at a comparable level and makes it as a valid drug target. In this study, an attempt is made to address the similarity in sequences and phylogenetic study of Calcium Dependent Protein Kinase 6 (CDPK6) among Calcium Dependent Protein Kinases of Apicomplexans. Further, the three-dimensional structure determination of CDPK6 of C. parvum was performed through a molecular modeling approach followed by virtual screening of small-molecule inhibitors from different datasets. The best inhibitor from Tres Cantos Antimalarial Set with ID 11730 reported a binding affinity of -8.2 kcal/mol against CDPK6 of C. parvum. Furthermore, the reliability of the binding mode of the inhibitor is validated through a complex molecular dynamics simulation study for a time interval of 100 ns. The simulation study advocates that the inhibitor Tres Cantos Antimalarial Set_11730 formed a stable interaction with the predicted active site residues and can be considered for industrial pharmaceutical research in future.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Ajit Kumar Dhal
- School of Biotechnology, KIIT Deemed to be University, Bhubaneswar, Odisha, India
| | - Alok Pani
- Department of Food Science and Technology, Jeonbuk National University, Jeonju, South Korea
| | - Soon-Il Yun
- Department of Food Science and Technology, Jeonbuk National University, Jeonju, South Korea
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Miyazaki S, Yang ASP, Geurten FJA, Marin-Mogollon C, Miyazaki Y, Imai T, Kolli SK, Ramesar J, Chevalley-Maurel S, Salman AM, van Gemert GJA, van Waardenburg YM, Franke-Fayard B, Hill AVS, Sauerwein RW, Janse CJ, Khan SM. Generation of Novel Plasmodium falciparum NF135 and NF54 Lines Expressing Fluorescent Reporter Proteins Under the Control of Strong and Constitutive Promoters. Front Cell Infect Microbiol 2020; 10:270. [PMID: 32587831 PMCID: PMC7298075 DOI: 10.3389/fcimb.2020.00270] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 05/06/2020] [Indexed: 12/18/2022] Open
Abstract
Transgenic reporter lines of malaria parasites that express fluorescent or luminescent proteins are valuable tools for drug and vaccine screening assays as well as to interrogate parasite gene function. Different Plasmodium falciparum (Pf ) reporter lines exist, however nearly all have been created in the African NF54/3D7 laboratory strain. Here we describe the generation of novel reporter lines, using CRISPR/Cas9 gene modification, both in the standard Pf NF54 background and in a recently described Cambodian P. falciparum NF135.C10 line. Sporozoites of this line show more effective hepatocyte invasion and enhanced liver merozoite development compared to Pf NF54. We first generated Pf NF54 reporter parasites to analyze two novel promoters for constitutive and high expression of mCherry-luciferase and GFP in blood and mosquito stages. The promoter sequences were selected based on available transcriptome data and are derived from two housekeeping genes, i.e., translation initiation factor SUI1, putative (sui1, PF3D7_1243600) and 40S ribosomal protein S30 (40s, PF3D7_0219200). We then generated and characterized reporter lines in the Pf NF135.C10 line which express GFP driven by the sui1 and 40s promoters as well as by the previously used ef1α promoter (GFP@ef1α, GFP@sui1, GFP@40s). The GFP@40s reporter line showed strongest GFP expression in liver stages as compared to the other two lines. The strength of reporter expression by the 40s promoter throughout the complete life cycle, including liver stages, makes transgenic lines expressing reporters by the 40s promoter valuable novel tools for analyses of P. falciparum.
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Affiliation(s)
- Shinya Miyazaki
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Annie S P Yang
- Department of Medical Microbiology, Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
| | - Fiona J A Geurten
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | | | - Yukiko Miyazaki
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Takashi Imai
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands.,Department of Infectious Diseases and Host Defense, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Surendra Kumar Kolli
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Jai Ramesar
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | | | - Ahmed M Salman
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Geert-Jan A van Gemert
- Department of Medical Microbiology, Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
| | - Youri M van Waardenburg
- Department of Medical Microbiology, Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
| | | | - Adrian V S Hill
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Robert W Sauerwein
- Department of Medical Microbiology, Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands.,TropIQ Health Sciences, Nijmegen, Netherlands
| | - Chris J Janse
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Shahid M Khan
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
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Abstract
As the world gets closer to eliminating malaria, the scientific community worldwide has begun to realize the importance of malaria transmission-blocking interventions. The onus of breaking the life cycle of the human malaria parasite Plasmodium falciparum predominantly rests upon transmission-blocking drugs because of emerging resistance to commonly used schizonticides and insecticides. This third part of our review series on malaria transmission-blocking entails transmission-blocking potential of preclinical transmission-blocking antimalarials and other non-malaria drugs/experimental compounds that are not in clinical or preclinical development for malaria but possess transmission-blocking potential. Collective analysis of the structure and the activity of these experimental compounds might pave the way toward generation of novel prototypes of next-generation transmission-blocking drugs.
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Ebstie YA, Guedoung ART, Habluetzel A. A murine malaria protocol for characterizing transmission blocking benefits of antimalarial drug combinations. MALARIAWORLD JOURNAL 2020; 11:1. [PMID: 34532220 PMCID: PMC8415060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
BACKGROUND Current efforts towards malaria elimination include the discovery of new transmission blocking (TB) drugs and identification of compounds suitable to replace primaquine, recommended as transmission blocking post treatment after artemisinin combination therapy (ACT). High through put screening of compound libraries has allowed to identify numerous compounds active in vitro against gametocytes and insect early sporogonic stages, but few studies have been performed to characterize TB compounds in vivo. Here we propose a double TB drug Direct Feeding Assay (2TB-DFA), suitable to assess the combined effects of TB compounds. MATERIALS AND METHODS Plasmodium berghei GFPcon (PbGFPcon), BALB/c mice and Anopheles stephensi mosquitoes were used. Artemisinin (ART) and artesunate (AS) served as examples of artemisinins, NeemAzal® (NA), as a known TB-product with sporontocidal activity. DFA experiments were performed to assess the appropriate time point of administration before mosquito feeding and estimate suitable sub-optimal doses of the three compounds that allow combination effects to be appreciated. RESULTS Suboptimal dosages, that reduce about 50% of oocyst development, were recorded with ART in the range of 16-30 mg/ kg, AS 14-28 mg/kg and NA 31-38mg/kg. Ten hours before mosquito feeding (corresponding to 3.5 days after mouse infection) was determined as a suitable time point for mouse treatment with ART and AS and 1 hour for post-treatment with NA. ART given at 35 mg/kg in combination with NA at 40 mg/kg reduced oocyst density by 94% and prevalence of infection by 59%. Similarly, the combination of ART at 25 mg/kg plus NA at 35 mg/kg decreased oocyst density by 95% and prevalence of infection by 34%. In the 2TB-DFA, conducted with AS (20 mg/kg) and NA (35 mg/kg) the combination treatment reduced oocyst density by 71% and did not affect prevalence of infection. Applying 'Highest Single Agent' analysis and considering as readout oocyst density and prevalence of infection, cooperative effects of the combination treatments, compared with the single compound treatments emerged. CONCLUSION This study suggests the 2TB-DFA to be suitable for the profiling of new TB candidates that could substitute primaquine as a post-treatment to ACT courses.
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Affiliation(s)
| | | | - Annette Habluetzel
- School of Pharmacy, University of Camerino, Camerino, Italy
- Centro Interuniversitario di Ricerca sulla Malaria/Italian Malaria Network, University of Milan, Milan, Italy
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Álvarez-Bardón M, Pérez-Pertejo Y, Ordóñez C, Sepúlveda-Crespo D, Carballeira NM, Tekwani BL, Murugesan S, Martinez-Valladares M, García-Estrada C, Reguera RM, Balaña-Fouce R. Screening Marine Natural Products for New Drug Leads against Trypanosomatids and Malaria. Mar Drugs 2020; 18:E187. [PMID: 32244488 PMCID: PMC7230869 DOI: 10.3390/md18040187] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 03/24/2020] [Accepted: 03/25/2020] [Indexed: 02/06/2023] Open
Abstract
Neglected Tropical Diseases (NTD) represent a serious threat to humans, especially for those living in poor or developing countries. Almost one-sixth of the world population is at risk of suffering from these diseases and many thousands die because of NTDs, to which we should add the sanitary, labor and social issues that hinder the economic development of these countries. Protozoan-borne diseases are responsible for more than one million deaths every year. Visceral leishmaniasis, Chagas disease or sleeping sickness are among the most lethal NTDs. Despite not being considered an NTD by the World Health Organization (WHO), malaria must be added to this sinister group. Malaria, caused by the apicomplexan parasite Plasmodium falciparum, is responsible for thousands of deaths each year. The treatment of this disease has been losing effectiveness year after year. Many of the medicines currently in use are obsolete due to their gradual loss of efficacy, their intrinsic toxicity and the emergence of drug resistance or a lack of adherence to treatment. Therefore, there is an urgent and global need for new drugs. Despite this, the scant interest shown by most of the stakeholders involved in the pharmaceutical industry makes our present therapeutic arsenal scarce, and until recently, the search for new drugs has not been seriously addressed. The sources of new drugs for these and other pathologies include natural products, synthetic molecules or repurposing drugs. The most frequent sources of natural products are microorganisms, e.g., bacteria, fungi, yeasts, algae and plants, which are able to synthesize many drugs that are currently in use (e.g. antimicrobials, antitumor, immunosuppressants, etc.). The marine environment is another well-established source of bioactive natural products, with recent applications against parasites, bacteria and other pathogens which affect humans and animals. Drug discovery techniques have rapidly advanced since the beginning of the millennium. The combination of novel techniques that include the genetic modification of pathogens, bioimaging and robotics has given rise to the standardization of High-Performance Screening platforms in the discovery of drugs. These advancements have accelerated the discovery of new chemical entities with antiparasitic effects. This review presents critical updates regarding the use of High-Throughput Screening (HTS) in the discovery of drugs for NTDs transmitted by protozoa, including malaria, and its application in the discovery of new drugs of marine origin.
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Affiliation(s)
- María Álvarez-Bardón
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - Yolanda Pérez-Pertejo
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - César Ordóñez
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - Daniel Sepúlveda-Crespo
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - Nestor M. Carballeira
- Department of Chemistry, University of Puerto Rico, Río Piedras 00925-2537, San Juan, Puerto Rico;
| | - Babu L. Tekwani
- Department of Infectious Diseases, Division of Drug Discovery, Southern Research, Birmingham, AL 35205, USA;
| | - Sankaranarayanan Murugesan
- Department of Pharmacy, Birla Institute of Technology and Science, Pilani Campus, Vidya Vihar, Pilani 333031, India;
| | - Maria Martinez-Valladares
- Department of Animal Health, Instituto de Ganadería de Montaña (CSIC-Universidad de León), Grulleros, 24346 León, Spain;
| | - Carlos García-Estrada
- INBIOTEC (Instituto de Biotecnología de León), Avda. Real 1-Parque Científico de León, 24006 León, Spain;
| | - Rosa M. Reguera
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - Rafael Balaña-Fouce
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
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Tibon NS, Ng CH, Cheong SL. Current progress in antimalarial pharmacotherapy and multi-target drug discovery. Eur J Med Chem 2019; 188:111983. [PMID: 31911292 DOI: 10.1016/j.ejmech.2019.111983] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 12/09/2019] [Accepted: 12/16/2019] [Indexed: 12/13/2022]
Abstract
Discovery and development of antimalarial drugs have long been dominated by single-target therapy. Continuous effort has been made to explore and identify different targets in malaria parasite crucial for the malaria treatment. The single-target drug therapy was initially successful, but it was later supplanted by combination therapy with multiple drugs to overcome drug resistance. Emergence of resistant strains even against the combination therapy has warranted a review of current antimalarial pharmacotherapy. This has led to the development of the new concept of covalent biotherapy, in which two or more pharmacophores are chemically bound to produce hybrid antimalarial drugs with multi-target functionalities. Herein, the review initially details the current pharmacotherapy for malaria as well as the conventional and novel targets of importance identified in the malaria parasite. Then, the rationale of multi-targeted therapy for malaria, approaches taken to develop the multi-target antimalarial hybrids, and the examples of hybrid molecules are comprehensively enumerated and discussed.
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Affiliation(s)
- Natasha Stella Tibon
- Department of Pharmaceutical Chemistry, School of Pharmacy, International Medical University, No. 126, Jalan Jalil Perkasa 19, Bukit Jalil, 57000, Kuala Lumpur, Malaysia
| | - Chew Hee Ng
- Department of Pharmaceutical Chemistry, School of Pharmacy, International Medical University, No. 126, Jalan Jalil Perkasa 19, Bukit Jalil, 57000, Kuala Lumpur, Malaysia.
| | - Siew Lee Cheong
- Department of Pharmaceutical Chemistry, School of Pharmacy, International Medical University, No. 126, Jalan Jalil Perkasa 19, Bukit Jalil, 57000, Kuala Lumpur, Malaysia.
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Abstract
The scientific community worldwide has realized that malaria elimination will not be possible without development of safe and effective transmission-blocking interventions. Primaquine, the only WHO recommended transmission-blocking drug, is not extensively utilized because of the toxicity issues in G6PD deficient individuals. Therefore, there is an urgent need to develop novel therapeutic interventions that can target malaria parasites and effectively block transmission. But at first, it is imperative to unravel the existing portfolio of transmission-blocking drugs. This review highlights transmission-blocking potential of current antimalarial drugs and drugs that are in various stages of clinical development. The collective analysis of the relationships between the structure and the activity of transmission-blocking drugs is expected to help in the design of new transmission-blocking antimalarials.
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25
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van der Watt ME, Reader J, Churchyard A, Nondaba SH, Lauterbach SB, Niemand J, Abayomi S, van Biljon RA, Connacher JI, van Wyk RDJ, Le Manach C, Paquet T, González Cabrera D, Brunschwig C, Theron A, Lozano-Arias S, Rodrigues JFI, Herreros E, Leroy D, Duffy J, Street LJ, Chibale K, Mancama D, Coetzer TL, Birkholtz LM. Potent Plasmodium falciparum gametocytocidal compounds identified by exploring the kinase inhibitor chemical space for dual active antimalarials. J Antimicrob Chemother 2019; 73:1279-1290. [PMID: 29420756 DOI: 10.1093/jac/dky008] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 01/02/2018] [Indexed: 01/06/2023] Open
Abstract
Objectives Novel chemical tools to eliminate malaria should ideally target both the asexual parasites and transmissible gametocytes. Several imidazopyridazines (IMPs) and 2-aminopyridines (2-APs) have been described as potent antimalarial candidates targeting lipid kinases. However, these have not been extensively explored for stage-specific inhibition of gametocytes in Plasmodium falciparum parasites. Here we provide an in-depth evaluation of the gametocytocidal activity of compounds from these chemotypes and identify novel starting points for dual-acting antimalarials. Methods We evaluated compounds against P. falciparum gametocytes using several assay platforms for cross-validation and stringently identified hits that were further profiled for stage specificity, speed of action and ex vivo efficacy. Physicochemical feature extraction and chemogenomic fingerprinting were applied to explore the kinase inhibition susceptibility profile. Results We identified 34 compounds with submicromolar activity against late stage gametocytes, validated across several assay platforms. Of these, 12 were potent at <100 nM (8 were IMPs and 4 were 2-APs) and were also active against early stage gametocytes and asexual parasites, with >1000-fold selectivity towards the parasite over mammalian cells. Front-runner compounds targeted mature gametocytes within 48 h and blocked transmission to mosquitoes. The resultant chemogenomic fingerprint of parasites treated with the lead compounds revealed the importance of targeting kinases in asexual parasites and gametocytes. Conclusions This study encompasses an in-depth evaluation of the kinase inhibitor space for gametocytocidal activity. Potent lead compounds have enticing dual activities and highlight the importance of targeting the kinase superfamily in malaria elimination strategies.
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Affiliation(s)
- Mariëtte E van der Watt
- Department of Biochemistry, Institute for Sustainable Malaria Control and South African Medical Research Council Collaborating Centre for Malaria Research, University of Pretoria, Private Bag x20, Hatfield, Pretoria 0028, South Africa
| | - Janette Reader
- Department of Biochemistry, Institute for Sustainable Malaria Control and South African Medical Research Council Collaborating Centre for Malaria Research, University of Pretoria, Private Bag x20, Hatfield, Pretoria 0028, South Africa
| | - Alisje Churchyard
- Plasmodium Molecular Research Unit, Wits Research Institute for Malaria, Department of Molecular Medicine and Haematology, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and National Health Laboratory Service, Johannesburg 2193, South Africa
| | - Sindisiwe H Nondaba
- Department of Biochemistry, Institute for Sustainable Malaria Control and South African Medical Research Council Collaborating Centre for Malaria Research, University of Pretoria, Private Bag x20, Hatfield, Pretoria 0028, South Africa
| | - Sonja B Lauterbach
- Plasmodium Molecular Research Unit, Wits Research Institute for Malaria, Department of Molecular Medicine and Haematology, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and National Health Laboratory Service, Johannesburg 2193, South Africa
| | - Jandeli Niemand
- Department of Biochemistry, Institute for Sustainable Malaria Control and South African Medical Research Council Collaborating Centre for Malaria Research, University of Pretoria, Private Bag x20, Hatfield, Pretoria 0028, South Africa
| | - Sijuade Abayomi
- Department of Biochemistry, Institute for Sustainable Malaria Control and South African Medical Research Council Collaborating Centre for Malaria Research, University of Pretoria, Private Bag x20, Hatfield, Pretoria 0028, South Africa
| | - Riëtte A van Biljon
- Department of Biochemistry, Institute for Sustainable Malaria Control and South African Medical Research Council Collaborating Centre for Malaria Research, University of Pretoria, Private Bag x20, Hatfield, Pretoria 0028, South Africa
| | - Jessica I Connacher
- Department of Biochemistry, Institute for Sustainable Malaria Control and South African Medical Research Council Collaborating Centre for Malaria Research, University of Pretoria, Private Bag x20, Hatfield, Pretoria 0028, South Africa
| | - Roelof D J van Wyk
- Department of Biochemistry, Institute for Sustainable Malaria Control and South African Medical Research Council Collaborating Centre for Malaria Research, University of Pretoria, Private Bag x20, Hatfield, Pretoria 0028, South Africa
| | - Claire Le Manach
- Drug Discovery and Development Centre (H3D), Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Tanya Paquet
- Drug Discovery and Development Centre (H3D), Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Diego González Cabrera
- Drug Discovery and Development Centre (H3D), Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Christel Brunschwig
- Drug Discovery and Development Centre (H3D), Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Anjo Theron
- Biosciences, Council for Scientific and Industrial Research, PO Box 395, Pretoria 0001, South Africa
| | - Sonia Lozano-Arias
- GlaxoSmithKline, Tres Cantos Medicines Development Campus, Severo Ochoa, 2, 28760 Tres Cantos, Madrid, Spain
| | - Janneth F I Rodrigues
- GlaxoSmithKline, Tres Cantos Medicines Development Campus, Severo Ochoa, 2, 28760 Tres Cantos, Madrid, Spain
| | - Esperanza Herreros
- GlaxoSmithKline, Tres Cantos Medicines Development Campus, Severo Ochoa, 2, 28760 Tres Cantos, Madrid, Spain
| | - Didier Leroy
- Medicines for Malaria Venture, International Center Cointrin, Route de Pré-Bois 20, 1215, Geneva, Switzerland
| | - James Duffy
- Medicines for Malaria Venture, International Center Cointrin, Route de Pré-Bois 20, 1215, Geneva, Switzerland
| | - Leslie J Street
- Drug Discovery and Development Centre (H3D), Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Kelly Chibale
- Drug Discovery and Development Centre (H3D), Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa.,South African Medical Research Council, Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 7701, South Africa
| | - Dalu Mancama
- Biosciences, Council for Scientific and Industrial Research, PO Box 395, Pretoria 0001, South Africa
| | - Theresa L Coetzer
- Plasmodium Molecular Research Unit, Wits Research Institute for Malaria, Department of Molecular Medicine and Haematology, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and National Health Laboratory Service, Johannesburg 2193, South Africa
| | - Lyn-Marie Birkholtz
- Department of Biochemistry, Institute for Sustainable Malaria Control and South African Medical Research Council Collaborating Centre for Malaria Research, University of Pretoria, Private Bag x20, Hatfield, Pretoria 0028, South Africa
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26
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Rout S, Mahapatra RK. In silico study of M18 aspartyl amino peptidase (M18AAP) of Plasmodium vivax as an antimalarial drug target. Bioorg Med Chem 2019; 27:2553-2571. [DOI: 10.1016/j.bmc.2019.03.039] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/16/2019] [Accepted: 03/19/2019] [Indexed: 12/20/2022]
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Abstract
In the progression of the life cycle of Plasmodium falciparum, a small proportion of asexual parasites differentiate into male or female sexual forms called gametocytes. Just like their asexual counterparts, gametocytes are contained within the infected host's erythrocytes (RBCs). However, unlike their asexual partners, they do not exit the RBC until they are taken up in a blood meal by a mosquito. In the mosquito midgut, they are stimulated to emerge from the RBC, undergo fertilization, and ultimately produce tens of thousands of sporozoites that are infectious to humans. This transmission cycle can be blocked by antibodies targeting proteins exposed on the parasite surface in the mosquito midgut, a process that has led to the development of candidate transmission-blocking vaccines (TBV), including some that are in clinical trials. Here we review the leading TBV antigens and highlight the ongoing search for additional gametocyte/gamete surface antigens, as well as antigens on the surfaces of gametocyte-infected erythrocytes, which can potentially become a new group of TBV candidates.
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Seneviratne AK, Xu M, Henao JJA, Fajardo VA, Hao Z, Voisin V, Xu GW, Hurren R, Kim S, MacLean N, Wang X, Gronda M, Jeyaraju D, Jitkova Y, Ketela T, Mullokandov M, Sharon D, Thomas G, Chouinard-Watkins R, Hawley JR, Schafer C, Yau HL, Khuchua Z, Aman A, Al-Awar R, Gross A, Claypool SM, Bazinet RP, Lupien M, Chan S, De Carvalho DD, Minden MD, Bader GD, Stark KD, LeBlanc P, Schimmer AD. The Mitochondrial Transacylase, Tafazzin, Regulates for AML Stemness by Modulating Intracellular Levels of Phospholipids. Cell Stem Cell 2019; 24:621-636.e16. [PMID: 30930145 DOI: 10.1016/j.stem.2019.02.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 12/19/2018] [Accepted: 02/27/2019] [Indexed: 12/17/2022]
Abstract
Tafazzin (TAZ) is a mitochondrial transacylase that remodels the mitochondrial cardiolipin into its mature form. Through a CRISPR screen, we identified TAZ as necessary for the growth and viability of acute myeloid leukemia (AML) cells. Genetic inhibition of TAZ reduced stemness and increased differentiation of AML cells both in vitro and in vivo. In contrast, knockdown of TAZ did not impair normal hematopoiesis under basal conditions. Mechanistically, inhibition of TAZ decreased levels of cardiolipin but also altered global levels of intracellular phospholipids, including phosphatidylserine, which controlled AML stemness and differentiation by modulating toll-like receptor (TLR) signaling.
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Affiliation(s)
- Ayesh K Seneviratne
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada; Institute of Medical Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Mingjing Xu
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Juan J Aristizabal Henao
- Laboratory of Nutritional Lipidomics, Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada
| | - Val A Fajardo
- Department of Health Sciences, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON, Canada
| | - Zhenyue Hao
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Veronique Voisin
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - G Wei Xu
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Rose Hurren
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - S Kim
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Neil MacLean
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Xiaoming Wang
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Marcela Gronda
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Danny Jeyaraju
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Yulia Jitkova
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Troy Ketela
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | | | - David Sharon
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Geethu Thomas
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | | | - James R Hawley
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Caitlin Schafer
- Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
| | - Helen Loo Yau
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Zaza Khuchua
- Department of Biochemistry, Sechenov Medical University, Moscow, Russian Federation; Institute of Medical Research Ilia State University, Tbilisi, Georgia
| | - Ahmed Aman
- Drug Discovery Program, Ontario Institute for Cancer Research, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, ON, Canada
| | - Rima Al-Awar
- Drug Discovery Program, Ontario Institute for Cancer Research, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, ON, Canada
| | - Atan Gross
- Department of Biological Regulation, Weizmann Institute, Rehovot, Israel
| | - Steven M Claypool
- Department of Physiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Mathieu Lupien
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Steven Chan
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Daniel D De Carvalho
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Mark D Minden
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Gary D Bader
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Ken D Stark
- Laboratory of Nutritional Lipidomics, Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada
| | - Paul LeBlanc
- Department of Health Sciences, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON, Canada
| | - Aaron D Schimmer
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada; Institute of Medical Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada.
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Moyo P, Kunyane P, Selepe MA, Eloff JN, Niemand J, Louw AI, Maharaj VJ, Birkholtz LM. Bioassay-guided isolation and identification of gametocytocidal compounds from Artemisia afra (Asteraceae). Malar J 2019; 18:65. [PMID: 30849984 PMCID: PMC6408838 DOI: 10.1186/s12936-019-2694-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 03/01/2019] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Optimal adoption of the malaria transmission-blocking strategy is currently limited by lack of safe and efficacious drugs. This has sparked the exploration of different sources of drugs in search of transmission-blocking agents. While plant species have been extensively investigated in search of malaria chemotherapeutic agents, comparatively less effort has been channelled towards exploring them in search of transmission-blocking drugs. Artemisia afra (Asteraceae), a prominent feature of South African folk medicine, is used for the treatment of a number of diseases, including malaria. In search of transmission-blocking compounds aimed against Plasmodium parasites, the current study endeavoured to isolate and identify gametocytocidal compounds from A. afra. METHODS A bioassay-guided isolation approach was adopted wherein a combination of solvent-solvent partitioning and gravity column chromatography was used. Collected fractions were continuously screened in vitro for their ability to inhibit the viability of primarily late-stage gametocytes of Plasmodium falciparum (NF54 strain), using a parasite lactate dehydrogenase assay. Chemical structures of isolated compounds were elucidated using UPLC-MS/MS and NMR data analysis. RESULTS Two guaianolide sesquiterpene lactones, 1α,4α-dihydroxybishopsolicepolide and yomogiartemin, were isolated and shown to be active (IC50 < 10 μg/ml; ~ 10 μM) against both gametocytes and intra-erythrocytic asexual P. falciparum parasites. Interestingly, 1α,4α-dihydroxybishopsolicepolide was significantly more potent against late-stage gametocytes than to early-stage gametocytes and intra-erythrocytic asexual P. falciparum parasites. Additionally, both isolated compounds were not overly cytotoxic against HepG2 cells in vitro. CONCLUSION This study provides the first instance of isolated compounds from A. afra against P. falciparum gametocytes as a starting point for further investigations on more plant species in search of transmission-blocking compounds.
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Affiliation(s)
- Phanankosi Moyo
- Malaria Parasite Molecular Laboratory, Department of Biochemistry, Genetics and Microbiology, Faculty of Natural and Agricultural Sciences, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Phaladi Kunyane
- Department of Chemistry, Faculty of Natural and Agricultural Sciences, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Mamoalosi A Selepe
- Department of Chemistry, Faculty of Natural and Agricultural Sciences, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Jacobus N Eloff
- Phytomedicine Programme, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Private Bag x04, Onderstepoort, Pretoria, 0110, South Africa
| | - Jandeli Niemand
- Malaria Parasite Molecular Laboratory, Department of Biochemistry, Genetics and Microbiology, Faculty of Natural and Agricultural Sciences, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Abraham I Louw
- Malaria Parasite Molecular Laboratory, Department of Biochemistry, Genetics and Microbiology, Faculty of Natural and Agricultural Sciences, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Vinesh J Maharaj
- Department of Chemistry, Faculty of Natural and Agricultural Sciences, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Lyn-Marie Birkholtz
- Malaria Parasite Molecular Laboratory, Department of Biochemistry, Genetics and Microbiology, Faculty of Natural and Agricultural Sciences, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa.
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30
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Rout S, Mahapatra RK. In silico analysis of plasmodium falciparum CDPK5 protein through molecular modeling, docking and dynamics. J Theor Biol 2019; 461:254-267. [DOI: 10.1016/j.jtbi.2018.10.045] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 10/15/2018] [Accepted: 10/22/2018] [Indexed: 10/28/2022]
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31
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Spicer TP, Gardiner DL, Schoenen FJ, Roy S, Griffin PR, Chase P, Scampavia L, Hodder P, Trenholme KR. Identification of Antimalarial Inhibitors Using Late-Stage Gametocytes in a Phenotypic Live/Dead Assay. SLAS DISCOVERY 2018; 24:38-46. [PMID: 30142014 DOI: 10.1177/2472555218796410] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Malaria remains a major cause of morbidity and mortality worldwide with ~3.3 billion people at risk of contracting malaria and an estimated 450,000 deaths each year. While tools to reduce the infection prevalence to low levels are currently under development, additional efforts will be required to interrupt transmission. Transmission between human host and vector by the malaria parasite involves gametogenesis in the host and uptake of gametocytes by the mosquito vector. This stage is a bottleneck for reproduction of the parasite, making it a target for small-molecule drug discovery. Targeting this stage, we used whole Plasmodium falciparum gametocytes from in vitro culture and implemented them into 1536-well plates to create a live/dead phenotypic antigametocyte assay. Using specialized equipment and upon further validation, we screened ~150,000 compounds from the NIH repository currently housed at Scripps Florida. We identified 100 primary screening hits that were tested for concentration response. Additional follow-up studies to determine specificity, potency, and increased efficacy of the antigametocyte candidate compounds resulted in a starting point for initial medicinal chemistry intervention. From this, 13 chemical analogs were subsequently tested as de novo powders, which confirmed original activity from the initial analysis and now provide a point of future engagement.
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Affiliation(s)
- Timothy P Spicer
- 1 Department of Molecular Medicine, The Scripps Research Institute, Scripps Florida, Jupiter, FL, USA.,2 School of Medicine, University of Queensland, Herston, Queensland, Australia
| | - Donald L Gardiner
- 2 School of Medicine, University of Queensland, Herston, Queensland, Australia
| | - Frank J Schoenen
- 3 The University of Kansas Specialized Chemistry Center, Lawrence, KS,USA
| | - Sudeshna Roy
- 3 The University of Kansas Specialized Chemistry Center, Lawrence, KS,USA.,4 The University of Mississippi, Oxford, MS
| | - Patrick R Griffin
- 1 Department of Molecular Medicine, The Scripps Research Institute, Scripps Florida, Jupiter, FL, USA
| | - Peter Chase
- 1 Department of Molecular Medicine, The Scripps Research Institute, Scripps Florida, Jupiter, FL, USA.,5 BMS, Hopewell, NJ
| | - Louis Scampavia
- 1 Department of Molecular Medicine, The Scripps Research Institute, Scripps Florida, Jupiter, FL, USA
| | - Peter Hodder
- 1 Department of Molecular Medicine, The Scripps Research Institute, Scripps Florida, Jupiter, FL, USA.,6 Amgen, Inc., Thousand Oaks, CA, USA
| | - Katharine R Trenholme
- 2 School of Medicine, University of Queensland, Herston, Queensland, Australia.,7 Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
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Antimalarial Transmission-Blocking Interventions: Past, Present, and Future. Trends Parasitol 2018; 34:735-746. [PMID: 30082147 DOI: 10.1016/j.pt.2018.07.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/14/2018] [Accepted: 07/02/2018] [Indexed: 12/17/2022]
Abstract
Malaria remains a major global health challenge. Appropriate use of current antimalarial tools has reduced the disease burden, but morbidity and mortality remain unacceptably high. It is widely accepted that, to achieve long-term control/eradication, it will be necessary to use interventions that inhibit the transmission of parasites to mosquitoes - these tools are termed transmission-blocking interventions (TBIs). This article aims to outline the rationale for the development of TBIs, with a focus on transmission-blocking drugs and (parasite-derived) transmission-blocking vaccines. We describe and summarise the current status of each of these intervention classes and attempt to identify future requirements in development, with a focus on the challenges of establishing each method within an integrated malarial control programme in the future.
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Artemisone and Artemiside Are Potent Panreactive Antimalarial Agents That Also Synergize Redox Imbalance in Plasmodium falciparum Transmissible Gametocyte Stages. Antimicrob Agents Chemother 2018; 62:AAC.02214-17. [PMID: 29866868 DOI: 10.1128/aac.02214-17] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 05/18/2018] [Indexed: 11/20/2022] Open
Abstract
The emergence of resistance toward artemisinin combination therapies (ACTs) by the malaria parasite Plasmodium falciparum has the potential to severely compromise malaria control. Therefore, the development of new artemisinins in combination with new drugs that impart activities toward both intraerythrocytic proliferative asexual and transmissible gametocyte stages, in particular, those of resistant parasites, is urgently required. We define artemisinins as oxidant drugs through their ability to oxidize reduced flavin cofactors of flavin disulfide reductases critical for maintaining redox homeostasis in the malaria parasite. Here we compare the activities of 10-amino artemisinin derivatives toward the asexual and gametocyte stages of P. falciparum parasites. Of these, artemisone and artemiside inhibited asexual and gametocyte stages, particularly stage V gametocytes, in the low-nanomolar range. Further, treatment of both early and late gametocyte stages with artemisone or artemiside combined with the pro-oxidant redox partner methylene blue displayed notable synergism. These data suggest that modulation of redox homeostasis is likely an important druggable process, particularly in gametocytes, and this finding thereby enhances the prospect of using combinations of oxidant and redox drugs for malaria control.
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34
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Ippolito MM, Johnson J, Mullin C, Mallow C, Morgan N, Wallender E, Li T, Rosenthal PJ. The Relative Effects of Artemether-lumefantrine and Non-artemisinin Antimalarials on Gametocyte Carriage and Transmission of Plasmodium falciparum: A Systematic Review and Meta-analysis. Clin Infect Dis 2018; 65:486-494. [PMID: 28402391 DOI: 10.1093/cid/cix336] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 04/07/2017] [Indexed: 11/14/2022] Open
Abstract
Background Artemisinin-based combination therapies (ACTs) have been widely adopted as first-line agents to treat uncomplicated falciparum malaria due to their activity against multidrug resistant parasites. ACTs may also disrupt transmission through a direct antigametocyte effect, but the extent of this effect is uncertain. We assessed the evidence for and estimated the effects of the most widely-deployed ACT, artemether-lumefantrine (AL), relative to non-ACTs on gametocyte clearance and transmission interruption. Methods We searched electronic databases for randomized controlled trials comparing AL to non-ACTs that reported gametocyte counts or results of mosquito-feeding assays. Two authors working independently assessed eligibility, extracted data, and evaluated the risk of bias. We conducted meta-analyses using a random-effects model. Results We identified 22 eligible trials. The pooled odds of gametocytemia at 1 week were lower in AL- compared to non-ACT-treated participants (odds ratio [OR] 0.09; 95% confidence interval [CI], 0.06-0.15; I2 = 0.60, P < .01; 15 trials). The odds of transmission to mosquitoes were also lower in AL treatment groups (OR 0.06; 95% CI, 0.00-0.47, P < .01 at 7 days post-treatment; 1 trial; OR 0.56; 95% CI, 0.36-0.88, P = .01 at 14 days post-treatment; 1 trial). Conclusion AL is superior to non-ACTs in reducing gametocytemia, and, based on limited evidence, abating transmission to mosquitoes. The transmission-limiting benefit of AL has relevance for policymakers planning optimal utilization of control strategies, including use of ACTs for malaria treatment and chemoprevention.
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Affiliation(s)
- Matthew M Ippolito
- Department of Medicine, Johns Hopkins University School of Medicine.,Graduate Training Program in Clinical Investigation, Johns Hopkins University Bloomberg School of Public Health
| | - Julia Johnson
- Graduate Training Program in Clinical Investigation, Johns Hopkins University Bloomberg School of Public Health.,Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Christopher Mullin
- Department of Medicine, Johns Hopkins University School of Medicine.,Graduate Training Program in Clinical Investigation, Johns Hopkins University Bloomberg School of Public Health
| | - Christopher Mallow
- Department of Medicine, Johns Hopkins University School of Medicine.,Graduate Training Program in Clinical Investigation, Johns Hopkins University Bloomberg School of Public Health
| | - Nadia Morgan
- Department of Medicine, Johns Hopkins University School of Medicine.,Graduate Training Program in Clinical Investigation, Johns Hopkins University Bloomberg School of Public Health
| | - Erika Wallender
- Department of Medicine, University of California San Francisco
| | - Tianjing Li
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
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Vu H, Pedro L, Mak T, McCormick B, Rowley J, Liu M, Di Capua A, Williams-Noonan B, Pham NB, Pouwer R, Nguyen B, Andrews KT, Skinner-Adams T, Kim J, Hol WGJ, Hui R, Crowther GJ, Van Voorhis WC, Quinn RJ. Fragment-Based Screening of a Natural Product Library against 62 Potential Malaria Drug Targets Employing Native Mass Spectrometry. ACS Infect Dis 2018; 4:431-444. [PMID: 29436819 PMCID: PMC5902791 DOI: 10.1021/acsinfecdis.7b00197] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
![]()
Natural
products are well known for their biological relevance, high degree
of three-dimensionality, and access to areas of largely unexplored
chemical space. To shape our understanding of the interaction between
natural products and protein targets in the postgenomic era, we have
used native mass spectrometry to investigate 62 potential protein
targets for malaria using a natural-product-based fragment library.
We reveal here 96 low-molecular-weight natural products identified
as binding partners of 32 of the putative malarial targets. Seventy-nine
(79) fragments have direct growth inhibition on Plasmodium
falciparum at concentrations that are promising for the development
of fragment hits against these protein targets. This adds a fragment
library to the published HTS active libraries in the public domain.
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Affiliation(s)
- Hoan Vu
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Liliana Pedro
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Tin Mak
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Brendan McCormick
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Jessica Rowley
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Miaomiao Liu
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Angela Di Capua
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Billy Williams-Noonan
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Ngoc B. Pham
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Rebecca Pouwer
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Bao Nguyen
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Katherine T. Andrews
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | - Tina Skinner-Adams
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
| | | | | | - Raymond Hui
- Structural Genomics Consortium, University of Toronto, MaRS South Tower, seventh floor 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | | | | | - Ronald J. Quinn
- Griffith Institute for Drug Discovery, Griffith University, 170 Kessels Road, Nathan, Queensland 4111, Australia
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Antimalarial agents against both sexual and asexual parasites stages: structure-activity relationships and biological studies of the Malaria Box compound 1-[5-(4-bromo-2-chlorophenyl)furan-2-yl]-N-[(piperidin-4-yl)methyl]methanamine (MMV019918) and analogues. Eur J Med Chem 2018; 150:698-718. [PMID: 29571157 DOI: 10.1016/j.ejmech.2018.03.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 03/06/2018] [Accepted: 03/08/2018] [Indexed: 01/31/2023]
Abstract
Therapies addressing multiple stages of Plasmodium falciparum life cycle are highly desirable for implementing malaria elimination strategies. MMV019918 (1, 1-[5-(4-bromo-2-chlorophenyl)furan-2-yl]-N-[(piperidin-4-yl)methyl]methanamine) was selected from the MMV Malaria Box for its dual activity against both asexual stages and gametocytes. In-depth structure-activity relationship studies and cytotoxicity evaluation led to the selection of 25 for further biological investigation. The potential transmission blocking activity of 25 versus P. falciparum was confirmed through the standard membrane-feeding assay. Both 1 and 25 significantly prolonged atrioventricular conduction time in Langendorff-isolated rat hearts, and showed inhibitory activity of Ba2+ current through Cav1.2 channels. An in silico target-fishing study suggested the enzyme phosphoethanolamine methyltransferase (PfPMT) as a potential target. However, compound activity against PfPMT did not track with the antiplasmodial activity, suggesting the latter activity relies on a different molecular target. Nevertheless, 25 showed interesting activity against PfPMT, which could be an important starting point for the identification of more potent inhibitors active against both sexual and asexual stages of the parasite.
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Targeted Phenotypic Screening in Plasmodium falciparum and Toxoplasma gondii Reveals Novel Modes of Action of Medicines for Malaria Venture Malaria Box Molecules. mSphere 2018; 3:mSphere00534-17. [PMID: 29359192 PMCID: PMC5770543 DOI: 10.1128/msphere.00534-17] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 12/20/2017] [Indexed: 01/23/2023] Open
Abstract
The Malaria Box collection includes 400 chemically diverse small molecules with documented potency against malaria parasite growth, but the underlying modes of action are largely unknown. Using complementary phenotypic screens against Plasmodium falciparum and Toxoplasma gondii, we report phenotype-specific hits based on inhibition of overall parasite growth, apicoplast segregation, and egress or host invasion, providing hitherto unavailable insights into the possible mechanisms affected. First, the Malaria Box library was screened against tachyzoite stage T. gondii and the half-maximal effective concentrations (EC50s) of molecules showing ≥80% growth inhibition at 10 µM were determined. Comparison of the EC50s for T. gondii and P. falciparum identified a subset of 24 molecules with nanomolar potency against both parasites. Thirty molecules that failed to induce acute growth inhibition in T. gondii tachyzoites in a 2-day assay caused delayed parasite death upon extended exposure, with at least three molecules interfering with apicoplast segregation during daughter cell formation. Using flow cytometry and microscopy-based examinations, we prioritized 26 molecules with the potential to inhibit host cell egress/invasion during asexual developmental stages of P. falciparum. None of the inhibitors affected digestive vacuole integrity, ruling out a mechanism mediated by broadly specific protease inhibitor activity. Interestingly, five of the plasmodial egress inhibitors inhibited ionophore-induced egress of T. gondii tachyzoites. These findings highlight the advantage of comparative and targeted phenotypic screens in related species as a means to identify lead molecules with a conserved mode of action. Further work on target identification and mechanism analysis will facilitate the development of antiparasitic compounds with cross-species efficacy. IMPORTANCE The phylum Apicomplexa includes many human and animal pathogens, such as Plasmodium falciparum (human malaria) and Toxoplasma gondii (human and animal toxoplasmosis). Widespread resistance to current antimalarials and the lack of a commercial vaccine necessitate novel pharmacological interventions with distinct modes of action against malaria. For toxoplasmosis, new drugs to effectively eliminate tissue-dwelling latent cysts of the parasite are needed. The Malaria Box antimalarial collection, managed and distributed by the Medicines for Malaria Venture, includes molecules of novel chemical classes with proven antimalarial efficacy. Using targeted phenotypic assays of P. falciparum and T. gondii, we have identified a subset of the Malaria Box molecules as potent inhibitors of plastid segregation and parasite invasion and egress, thereby providing early insights into their probable mode of action. Five molecules that inhibit the egress of both parasites have been identified for further mechanistic studies. Thus, the approach we have used to identify novel molecules with defined modes of action in multiple parasites can expedite the development of pan-active antiparasitic agents.
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38
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Wadi I, Pillai CR, Anvikar AR, Sinha A, Nath M, Valecha N. Methylene blue induced morphological deformations in Plasmodium falciparum gametocytes: implications for transmission-blocking. Malar J 2018; 17:11. [PMID: 29310655 PMCID: PMC5759873 DOI: 10.1186/s12936-017-2153-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 12/23/2017] [Indexed: 12/24/2022] Open
Abstract
Background Malaria remains a global health problem despite availability of effective tools. For malaria elimination, drugs targeting sexual stages of Plasmodium falciparum need to be incorporated in treatment regimen along with schizonticidal drugs to interrupt transmission. Primaquine is recommended as a transmission blocking drug for its effect on mature gametocytes but is not extensively utilized because of associated safety concerns among glucose-6-phosphate dehydrogenase (G6PD) deficient patients. In present work, methylene blue, which is proposed as an alternative to primaquine is investigated for its gametocytocidal activity amongst Indian field isolates. An effort has been made to establish Indian field isolates of P. falciparum as in vitro model for gametocytocidal drugs screening. Methods Plasmodium falciparum isolates were adapted to in vitro culture and induced to gametocyte production by hypoxanthine and culture was enriched for gametocyte stages using N-acetyl-glucosamine. Gametocytes were incubated with methylene blue for 48 h and stage specific gametocytocidal activity was evaluated by microscopic examination. Results Plasmodium falciparum field isolates RKL-9 and JDP-8 were able to reproducibly produce gametocytes in high yield and were used to screen gametocytocidal drugs. Methylene blue was found to target gametocytes in a concentration dependent manner by either completely eliminating gametocytes or rendering them morphologically deformed with mean IC50 (early stages) as 424.1 nM and mean IC50 (late stages) as 106.4 nM. These morphologically altered gametocytes appeared highly degenerated having shrinkage, distortions and membrane deformations. Conclusions Field isolates that produce gametocytes in high yield in vitro can be identified and used to screen gametocytocidal drugs. These isolates should be used for validation of gametocytocidal hits obtained previously by using lab adapted reference strains. Methylene blue was found to target gametocytes produced from Indian field isolates and is proposed to be used as a gametocytocidal adjunct with artemisinin-based combination therapy. Further exploration of methylene blue in clinical studies amongst Indian population, including G6PD deficient patients, is recommended.
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Affiliation(s)
- Ishan Wadi
- Indian Council of Medical Research-National Institute of Malaria Research, Sector 8, Dwarka, New Delhi, 110077, India. .,Department of Chemistry, University of Delhi, Delhi, 110007, India.
| | - C Radhakrishna Pillai
- Indian Council of Medical Research-National Institute of Malaria Research, Sector 8, Dwarka, New Delhi, 110077, India
| | - Anupkumar R Anvikar
- Indian Council of Medical Research-National Institute of Malaria Research, Sector 8, Dwarka, New Delhi, 110077, India
| | - Abhinav Sinha
- Indian Council of Medical Research-National Institute of Malaria Research, Sector 8, Dwarka, New Delhi, 110077, India
| | - Mahendra Nath
- Department of Chemistry, University of Delhi, Delhi, 110007, India
| | - Neena Valecha
- Indian Council of Medical Research-National Institute of Malaria Research, Sector 8, Dwarka, New Delhi, 110077, India
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39
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Sinha S, Sarma P, Sehgal R, Medhi B. Development in Assay Methods for in Vitro Antimalarial Drug Efficacy Testing: A Systematic Review. Front Pharmacol 2017; 8:754. [PMID: 29123481 PMCID: PMC5662882 DOI: 10.3389/fphar.2017.00754] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 10/04/2017] [Indexed: 11/13/2022] Open
Abstract
The emergence and spread of drug resistance are the major challenges in malaria eradication mission. Besides various strategies laid down by World Health Organization, such as vector management, source reduction, early case detection, prompt treatment, and development of new diagnostics and vaccines, nevertheless the need for new and efficacious drugs against malaria has become a critical priority on the global malaria research agenda. At several screening stages, millions of compounds are screened (1,000–2,000,000 compounds per screening campaign), before pre-clinical trials to select optimum lead. Carrying out in vitro screening of antimalarials is very difficult as different assay methods are subject to numerous sources of variability across different laboratories around the globe. Despite this, in vitro screening is an essential part of antimalarial drug development as it enables to resource various confounding factors such as host immune response and drug–drug interaction. Therefore, in this article, we try to illustrate the basic necessity behind in vitro study and how new methods are developed and subsequently adopted for high-throughput antimalarial drug screening and its application in achieving the next level of in vitro screening based on the current approaches (such as stem cells).
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Affiliation(s)
- Shweta Sinha
- Department of Medical Parasitology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Phulen Sarma
- Department of Pharmacology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Rakesh Sehgal
- Department of Medical Parasitology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Bikash Medhi
- Department of Pharmacology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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40
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Chirawurah JD, Ansah F, Nyarko PB, Duodu S, Aniweh Y, Awandare GA. Antimalarial activity of Malaria Box Compounds against Plasmodium falciparum clinical isolates. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2017; 7:399-406. [PMID: 29128848 PMCID: PMC5683671 DOI: 10.1016/j.ijpddr.2017.10.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 10/06/2017] [Accepted: 10/12/2017] [Indexed: 12/18/2022]
Abstract
Malaria remains a major cause of childhood deaths in resource-limited settings. In the absence of an effective vaccine, drugs and other interventions have played very significant roles in combating the scourge of malaria. The recent reports of resistance to artemisinin necessitate the need for new antimalarial drugs with novel mechanisms of action. Towards the development of new, affordable and easily accessible antimalarial drugs for endemic regions, the Medicines for Malaria Venture (MMV) assembled a total of 400 active antimalarial compounds called the Malaria Box. The potency and the efficacy of the Malaria Box Compounds have been determined mainly using laboratory strains of P. falciparum. This study investigated the potency of twenty compounds from the Malaria Box against four clinical isolates from Ghana, using optimized in vitro growth inhibitory assays. Seven out of the 20 compounds screened had 50% inhibitory concentration (IC50) below 500 nM. The most active among the selected compounds was MMV006087 (average IC50 of 30.79 nM). Variations in the potency of the Malaria Box Compounds were observed between P. falciparum clinical isolates and Dd2 strain. We also investigated the sensitivity of the clinical isolates to chloroquine and artesunate. The N093 clinical isolate was found to be resistant to chloroquine but showed high sensitivity to artesunate. The results underscore the importance of including clinical isolates with different drug-resistant backgrounds, in addition to laboratory strains, in validating potential compounds during antimalarial compound screening programs.
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Affiliation(s)
- Jersley D Chirawurah
- West African Center for Cell Biology of Infectious Pathogens and Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P. O. Box LG 54, Volta Road Legon, Accra, Ghana
| | - Felix Ansah
- West African Center for Cell Biology of Infectious Pathogens and Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P. O. Box LG 54, Volta Road Legon, Accra, Ghana
| | - Prince B Nyarko
- West African Center for Cell Biology of Infectious Pathogens and Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P. O. Box LG 54, Volta Road Legon, Accra, Ghana
| | - Samuel Duodu
- West African Center for Cell Biology of Infectious Pathogens and Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P. O. Box LG 54, Volta Road Legon, Accra, Ghana
| | - Yaw Aniweh
- West African Center for Cell Biology of Infectious Pathogens and Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P. O. Box LG 54, Volta Road Legon, Accra, Ghana.
| | - Gordon A Awandare
- West African Center for Cell Biology of Infectious Pathogens and Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P. O. Box LG 54, Volta Road Legon, Accra, Ghana.
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41
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Screening the Medicines for Malaria Venture Pathogen Box across Multiple Pathogens Reclassifies Starting Points for Open-Source Drug Discovery. Antimicrob Agents Chemother 2017; 61:AAC.00379-17. [PMID: 28674055 PMCID: PMC5571359 DOI: 10.1128/aac.00379-17] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 06/19/2017] [Indexed: 01/19/2023] Open
Abstract
Open-access drug discovery provides a substantial resource for diseases primarily affecting the poor and disadvantaged. The open-access Pathogen Box collection is comprised of compounds with demonstrated biological activity against specific pathogenic organisms. The supply of this resource by the Medicines for Malaria Venture has the potential to provide new chemical starting points for a number of tropical and neglected diseases, through repurposing of these compounds for use in drug discovery campaigns for these additional pathogens. We tested the Pathogen Box against kinetoplastid parasites and malaria life cycle stages in vitro Consequently, chemical starting points for malaria, human African trypanosomiasis, Chagas disease, and leishmaniasis drug discovery efforts have been identified. Inclusive of this in vitro biological evaluation, outcomes from extensive literature reviews and database searches are provided. This information encompasses commercial availability, literature reference citations, other aliases and ChEMBL number with associated biological activity, where available. The release of this new data for the Pathogen Box collection into the public domain will aid the open-source model of drug discovery. Importantly, this will provide novel chemical starting points for drug discovery and target identification in tropical disease research.
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42
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Vanaerschot M, Lucantoni L, Li T, Combrinck JM, Ruecker A, Kumar TRS, Rubiano K, Ferreira PE, Siciliano G, Gulati S, Henrich PP, Ng CL, Murithi JM, Corey VC, Duffy S, Lieberman OJ, Veiga MI, Sinden RE, Alano P, Delves MJ, Lee Sim K, Winzeler EA, Egan TJ, Hoffman SL, Avery VM, Fidock DA. Hexahydroquinolines are antimalarial candidates with potent blood-stage and transmission-blocking activity. Nat Microbiol 2017. [PMID: 28808258 DOI: 10.1038/s41564-017-0007–4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Antimalarial compounds with dual therapeutic and transmission-blocking activity are desired as high-value partners for combination therapies. Here, we report the identification and characterization of hexahydroquinolines (HHQs) that show low nanomolar potency against both pathogenic and transmissible intra-erythrocytic forms of the malaria parasite Plasmodium falciparum. This activity translates into potent transmission-blocking potential, as shown by in vitro male gamete formation assays and reduced oocyst infection and prevalence in Anopheles mosquitoes. In vivo studies illustrated the ability of lead HHQs to suppress Plasmodium berghei blood-stage parasite proliferation. Resistance selection studies, confirmed by CRISPR-Cas9-based gene editing, identified the digestive vacuole membrane-spanning transporter PfMDR1 (P. falciparum multidrug resistance gene-1) as a determinant of parasite resistance to HHQs. Haemoglobin and haem fractionation assays suggest a mode of action that results in reduced haemozoin levels and might involve inhibition of host haemoglobin uptake into intra-erythrocytic parasites. Furthermore, parasites resistant to HHQs displayed increased susceptibility to several first-line antimalarial drugs, including lumefantrine, confirming that HHQs have a different mode of action to other antimalarials drugs for which PfMDR1 is known to confer resistance. This work evokes therapeutic strategies that combine opposing selective pressures on this parasite transporter as an approach to countering the emergence and transmission of multidrug-resistant P. falciparum malaria.
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Affiliation(s)
- Manu Vanaerschot
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Leonardo Lucantoni
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan, 4111, Queensland, Australia
| | - Tao Li
- Sanaria Inc., Rockville, MD, 20852, USA
| | - Jill M Combrinck
- Division of Pharmacology, Department of Medicine, University of Cape Town, Cape Town, 7925, South Africa
| | - Andrea Ruecker
- Department of Life Sciences, Imperial College, London, SW7 2AZ, UK.,Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7FZ, UK
| | - T R Santha Kumar
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Kelly Rubiano
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Pedro E Ferreira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057, Braga, Portugal
| | - Giulia Siciliano
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, 00161, Rome, Italy
| | - Sonia Gulati
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Philipp P Henrich
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Caroline L Ng
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - James M Murithi
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Victoria C Corey
- University of California, San Diego, School of Medicine, La Jolla, CA, 92093, USA
| | - Sandra Duffy
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan, 4111, Queensland, Australia
| | - Ori J Lieberman
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - M Isabel Veiga
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057, Braga, Portugal
| | - Robert E Sinden
- Department of Life Sciences, Imperial College, London, SW7 2AZ, UK
| | - Pietro Alano
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, 00161, Rome, Italy
| | - Michael J Delves
- Department of Life Sciences, Imperial College, London, SW7 2AZ, UK
| | | | - Elizabeth A Winzeler
- University of California, San Diego, School of Medicine, La Jolla, CA, 92093, USA
| | - Timothy J Egan
- Department of Chemistry, University of Cape Town, Cape Town, 7700, South Africa
| | | | - Vicky M Avery
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan, 4111, Queensland, Australia
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA. .,Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, NY, 10032, USA.
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43
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Vanaerschot M, Lucantoni L, Li T, Combrinck JM, Ruecker A, Kumar TRS, Rubiano K, Ferreira PE, Siciliano G, Gulati S, Henrich PP, Ng CL, Murithi JM, Corey VC, Duffy S, Lieberman OJ, Veiga MI, Sinden RE, Alano P, Delves MJ, Lee Sim K, Winzeler EA, Egan TJ, Hoffman SL, Avery VM, Fidock DA. Hexahydroquinolines are antimalarial candidates with potent blood-stage and transmission-blocking activity. Nat Microbiol 2017; 2:1403-1414. [PMID: 28808258 DOI: 10.1038/s41564-017-0007-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 07/11/2017] [Indexed: 12/21/2022]
Abstract
Antimalarial compounds with dual therapeutic and transmission-blocking activity are desired as high-value partners for combination therapies. Here, we report the identification and characterization of hexahydroquinolines (HHQs) that show low nanomolar potency against both pathogenic and transmissible intra-erythrocytic forms of the malaria parasite Plasmodium falciparum. This activity translates into potent transmission-blocking potential, as shown by in vitro male gamete formation assays and reduced oocyst infection and prevalence in Anopheles mosquitoes. In vivo studies illustrated the ability of lead HHQs to suppress Plasmodium berghei blood-stage parasite proliferation. Resistance selection studies, confirmed by CRISPR-Cas9-based gene editing, identified the digestive vacuole membrane-spanning transporter PfMDR1 (P. falciparum multidrug resistance gene-1) as a determinant of parasite resistance to HHQs. Haemoglobin and haem fractionation assays suggest a mode of action that results in reduced haemozoin levels and might involve inhibition of host haemoglobin uptake into intra-erythrocytic parasites. Furthermore, parasites resistant to HHQs displayed increased susceptibility to several first-line antimalarial drugs, including lumefantrine, confirming that HHQs have a different mode of action to other antimalarials drugs for which PfMDR1 is known to confer resistance. This work evokes therapeutic strategies that combine opposing selective pressures on this parasite transporter as an approach to countering the emergence and transmission of multidrug-resistant P. falciparum malaria.
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Affiliation(s)
- Manu Vanaerschot
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Leonardo Lucantoni
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan, 4111, Queensland, Australia
| | - Tao Li
- Sanaria Inc., Rockville, MD, 20852, USA
| | - Jill M Combrinck
- Division of Pharmacology, Department of Medicine, University of Cape Town, Cape Town, 7925, South Africa
| | - Andrea Ruecker
- Department of Life Sciences, Imperial College, London, SW7 2AZ, UK.,Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7FZ, UK
| | - T R Santha Kumar
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Kelly Rubiano
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Pedro E Ferreira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057, Braga, Portugal
| | - Giulia Siciliano
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, 00161, Rome, Italy
| | - Sonia Gulati
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Philipp P Henrich
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Caroline L Ng
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - James M Murithi
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Victoria C Corey
- University of California, San Diego, School of Medicine, La Jolla, CA, 92093, USA
| | - Sandra Duffy
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan, 4111, Queensland, Australia
| | - Ori J Lieberman
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - M Isabel Veiga
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057, Braga, Portugal
| | - Robert E Sinden
- Department of Life Sciences, Imperial College, London, SW7 2AZ, UK
| | - Pietro Alano
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, 00161, Rome, Italy
| | - Michael J Delves
- Department of Life Sciences, Imperial College, London, SW7 2AZ, UK
| | | | - Elizabeth A Winzeler
- University of California, San Diego, School of Medicine, La Jolla, CA, 92093, USA
| | - Timothy J Egan
- Department of Chemistry, University of Cape Town, Cape Town, 7700, South Africa
| | | | - Vicky M Avery
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan, 4111, Queensland, Australia
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA. .,Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, NY, 10032, USA.
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44
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Affiliation(s)
- Robert E. Sinden
- Department of Life Sciences, Imperial College London, London, United Kingdom
- * E-mail:
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45
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The need to compare: assessing the level of agreement of three high-throughput assays against Plasmodium falciparum mature gametocytes. Sci Rep 2017; 7:45992. [PMID: 28378767 PMCID: PMC5380998 DOI: 10.1038/srep45992] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 03/07/2017] [Indexed: 12/22/2022] Open
Abstract
Whole-cell High-Throughput Screening (HTS) is a key tool for the discovery of much needed malaria transmission blocking drugs. Discrepancies in the reported outcomes from various HTS Plasmodium falciparum gametocytocidal assays hinder the direct comparison of data and ultimately the interpretation of the transmission blocking potential of hits. To dissect the underlying determinants of such discrepancies and assess the impact that assay-specific factors have on transmission-blocking predictivity, a 39-compound subset from the Medicines for Malaria Venture Malaria Box was tested in parallel against three distinct mature stage gametocytocidal assays, under strictly controlled parasitological, chemical, temporal and analytical conditions resembling the standard membrane feeding assay (SMFA). Apart from a few assay-specific outliers, which highlighted the value of utilizing multiple complementary approaches, good agreement was observed (average ΔpIC50 of 0.12 ± 0.01). Longer compound incubation times improved the ability of the least sensitive assay to detect actives by 2-fold. Finally, combining the number of actives identified by any single assay with those obtained at longer incubation times yielded greatly improved outcomes and agreement with SMFA. Screening compounds using extended incubation times and using multiple in vitro assay technologies are valid approaches for the efficient identification of biologically relevant malaria transmission blocking hits.
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46
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Pegoraro S, Duffey M, Otto TD, Wang Y, Rösemann R, Baumgartner R, Fehler SK, Lucantoni L, Avery VM, Moreno-Sabater A, Mazier D, Vial HJ, Strobl S, Sanchez CP, Lanzer M. SC83288 is a clinical development candidate for the treatment of severe malaria. Nat Commun 2017; 8:14193. [PMID: 28139658 PMCID: PMC5290327 DOI: 10.1038/ncomms14193] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 12/07/2016] [Indexed: 01/11/2023] Open
Abstract
Severe malaria is a life-threatening complication of an infection with the protozoan parasite Plasmodium falciparum, which requires immediate treatment. Safety and efficacy concerns with currently used drugs accentuate the need for new chemotherapeutic options against severe malaria. Here we describe a medicinal chemistry program starting from amicarbalide that led to two compounds with optimized pharmacological and antiparasitic properties. SC81458 and the clinical development candidate, SC83288, are fast-acting compounds that can cure a P. falciparum infection in a humanized NOD/SCID mouse model system. Detailed preclinical pharmacokinetic and toxicological studies reveal no observable drawbacks. Ultra-deep sequencing of resistant parasites identifies the sarco/endoplasmic reticulum Ca2+ transporting PfATP6 as a putative determinant of resistance to SC81458 and SC83288. Features, such as fast parasite killing, good safety margin, a potentially novel mode of action and a distinct chemotype support the clinical development of SC83288, as an intravenous application for the treatment of severe malaria.
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Affiliation(s)
| | - Maëlle Duffey
- Department of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
- German Center for Infection Research (DZIF), partner site Heidelberg, 69120 Heidelberg, Germany
| | - Thomas D Otto
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton CB10 1SA, UK
| | - Yulin Wang
- Department of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
- German Center for Infection Research (DZIF), partner site Heidelberg, 69120 Heidelberg, Germany
| | - Roman Rösemann
- 4SC Discovery GmbH, Am Klopferspitz 19a, 82152 Martinsried, Germany
| | | | - Stefanie K Fehler
- 4SC AG, Am Klopferspitz 19a, 82152 Martinsried, Germany
- Department of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
- German Center for Infection Research (DZIF), partner site Heidelberg, 69120 Heidelberg, Germany
| | - Leonardo Lucantoni
- Eskitis Institute for Drug Discovery, Griffith University, Don Young, Nathan Queensland 4111, Australia
| | - Vicky M Avery
- Eskitis Institute for Drug Discovery, Griffith University, Don Young, Nathan Queensland 4111, Australia
| | - Alicia Moreno-Sabater
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U1135, CNRS ERL 8255, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France
- AP-HP, Hôpital St Antoine, Service de Parasitologie-Mycologie, F-75012 Paris, France
| | - Dominique Mazier
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U1135, CNRS ERL 8255, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France
- AP-HP, Groupe hospitalier La Pitié-Salpêtrière, Service de Parasitologie-Mycologie, F-75013 Paris, France
| | - Henri J Vial
- Dynamique des Interactions Membranaires Normales et Pathologiques, CNRS UMR 5235, Université Montpellier II, cc107, Place Eugène Bataillon, 34095 Montpellier, France
| | - Stefan Strobl
- 4SC Discovery GmbH, Am Klopferspitz 19a, 82152 Martinsried, Germany
| | - Cecilia P Sanchez
- Department of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
- German Center for Infection Research (DZIF), partner site Heidelberg, 69120 Heidelberg, Germany
| | - Michael Lanzer
- Department of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
- German Center for Infection Research (DZIF), partner site Heidelberg, 69120 Heidelberg, Germany
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Fletcher S, Lucantoni L, Sykes ML, Jones AJ, Holleran JP, Saliba KJ, Avery VM. Biological characterization of chemically diverse compounds targeting the Plasmodium falciparum coenzyme A synthesis pathway. Parasit Vectors 2016; 9:589. [PMID: 27855724 PMCID: PMC5114727 DOI: 10.1186/s13071-016-1860-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 10/27/2016] [Indexed: 01/10/2023] Open
Abstract
Background In the fight against malaria, the discovery of chemical compounds with a novel mode of action and/or chemistry distinct from currently used drugs is vital to counteract the parasite’s known ability to develop drug resistance. Another desirable aspect is efficacy against gametocytes, the sexual developmental stage of the parasite which enables the transmission through Anopheles vectors. Using a chemical rescue approach, we previously identified compounds targeting Plasmodium falciparum coenzyme A (CoA) synthesis or utilization, a promising target that has not yet been exploited in anti-malarial drug development. Results We report on the outcomes of a series of biological tests that help to define the species- and stage-specificity, as well as the potential targets of these chemically diverse compounds. Compound activity against P. falciparum gametocytes was determined to assess stage-specificity and transmission-reducing potential. Against early stage gametocytes IC50 values ranging between 60 nM and 7.5 μM were obtained. With the exception of two compounds with sub-micromolar potencies across all intra-erythrocytic stages, activity against late stage gametocytes was lower. None of the compounds were specific pantothenate kinase inhibitors. Chemical rescue profiling with CoA pathway intermediates demonstrated that most compounds acted on either of the two final P. falciparum CoA synthesis enzymes, phosphopantetheine adenylyltransferase (PPAT) or dephospho CoA kinase (DPCK). The most active compound targeted either phosphopantothenoylcysteine synthetase (PPCS) or phosphopantothenoylcysteine decarboxylase (PPCDC). Species-specificity was evaluated against Trypanosoma cruzi and Trypanosoma brucei brucei. No specific activity against T. cruzi amastigotes was observed; however three compounds inhibited the viability of trypomastigotes with sub-micromolar potencies and were confirmed to act on T. b. brucei CoA synthesis. Conclusions Utilizing the compounds we previously identified as effective against asexual P. falciparum, we demonstrate for the first time that gametocytes, like the asexual stages, depend on CoA, with two compounds exhibiting sub-micromolar potencies across asexual forms and all gametocytes stages tested. Furthermore, three compounds inhibited the viability of T. cruzi and T. b. brucei trypomastigotes with sub-micromolar potencies and were confirmed to act on T. b. brucei CoA synthesis, indicating that the CoA synthesis pathway might represent a valuable new drug target in these parasite species. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1860-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sabine Fletcher
- Discovery Biology, Eskitis Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Leonardo Lucantoni
- Discovery Biology, Eskitis Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Melissa L Sykes
- Discovery Biology, Eskitis Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Amy J Jones
- Discovery Biology, Eskitis Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - John P Holleran
- Discovery Biology, Eskitis Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Kevin J Saliba
- Medical School and Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Vicky M Avery
- Discovery Biology, Eskitis Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia.
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Abstract
This article attempts to draw together current knowledge on the biology of Plasmodium and experience gained from past control campaigns to interpret and guide current efforts to discover and develop exciting new strategies targeting the parasite with the objective of interrupting transmission. Particular note is made of the advantages of targeting often unappreciated small, yet vital, bottleneck populations to enhance both the impact and the useful lifetime of hard-won interventions. A case is made for the standardization of methods to measure transmission blockade to permit the rational comparison of how diverse interventions (drugs, vaccines, insecticides, Genetically Modified technologies) targeting disparate aspects of parasite biology may impact upon the commonly used parameter of parasite prevalence in the human population.
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Affiliation(s)
- R E Sinden
- The Jenner Institute, Oxford, United Kingdom.
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49
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Metabolomic Profiling of the Malaria Box Reveals Antimalarial Target Pathways. Antimicrob Agents Chemother 2016; 60:6635-6649. [PMID: 27572391 DOI: 10.1128/aac.01224-16] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 08/16/2016] [Indexed: 12/11/2022] Open
Abstract
The threat of widespread drug resistance to frontline antimalarials has renewed the urgency for identifying inexpensive chemotherapeutic compounds that are effective against Plasmodium falciparum, the parasite species responsible for the greatest number of malaria-related deaths worldwide. To aid in the fight against malaria, a recent extensive screening campaign has generated thousands of lead compounds with low micromolar activity against blood stage parasites. A subset of these leads has been compiled by the Medicines for Malaria Venture (MMV) into a collection of structurally diverse compounds known as the MMV Malaria Box. Currently, little is known regarding the activity of these Malaria Box compounds on parasite metabolism during intraerythrocytic development, and a majority of the targets for these drugs have yet to be defined. Here we interrogated the in vitro metabolic effects of 189 drugs (including 169 of the drug-like compounds from the Malaria Box) using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS). The resulting metabolic fingerprints provide information on the parasite biochemical pathways affected by pharmacologic intervention and offer a critical blueprint for selecting and advancing lead compounds as next-generation antimalarial drugs. Our results reveal several major classes of metabolic disruption, which allow us to predict the mode of action (MoA) for many of the Malaria Box compounds. We anticipate that future combination therapies will be greatly informed by these results, allowing for the selection of appropriate drug combinations that simultaneously target multiple metabolic pathways, with the aim of eliminating malaria and forestalling the expansion of drug-resistant parasites in the field.
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50
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Edwards RL, Odom John AR. Muddled mechanisms: recent progress towards antimalarial target identification. F1000Res 2016; 5:2514. [PMID: 27803804 PMCID: PMC5070598 DOI: 10.12688/f1000research.9477.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/06/2016] [Indexed: 01/06/2023] Open
Abstract
In the past decade, malaria rates have plummeted as a result of aggressive infection control measures and the adoption of artemisinin-based combination therapies (ACTs). However, a potential crisis looms ahead. Treatment failures to standard antimalarial regimens have been reported in Southeast Asia, and devastating consequences are expected if resistance spreads to the African continent. To prevent a potential public health emergency, the antimalarial arsenal must contain therapeutics with novel mechanisms of action (MOA). An impressive number of high-throughput screening (HTS) campaigns have since been launched, identifying thousands of compounds with activity against one of the causative agents of malaria,
Plasmodium falciparum. Now begins the difficult task of target identification, for which studies are often tedious, labor intensive, and difficult to interpret. In this review, we highlight approaches that have been instrumental in tackling the challenges of target assignment and elucidation of the MOA for hit compounds. Studies that apply these innovative techniques to antimalarial target identification are described, as well as the impact of the data in the field.
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Affiliation(s)
- Rachel L Edwards
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - Audrey R Odom John
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA; Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, USA
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