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Orbán Á, Schumacher JJ, Mucza S, Strinic A, Molnár P, Babai R, Halbritter A, Vértessy BG, Karl S, Krohns S, Kézsmárki I. Magneto-optical assessment of Plasmodium parasite growth via hemozoin crystal size. Sci Rep 2024; 14:14318. [PMID: 38906910 PMCID: PMC11192761 DOI: 10.1038/s41598-024-60988-6] [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: 02/15/2023] [Accepted: 04/30/2024] [Indexed: 06/23/2024] Open
Abstract
Hemozoin is a natural biomarker formed during the hemoglobin metabolism of Plasmodium parasites, the causative agents of malaria. The rotating-crystal magneto-optical detection (RMOD) has been developed for its rapid and sensitive detection both in cell cultures and patient samples. In the current article we demonstrate that, besides quantifying the overall concentration of hemozoin produced by the parasites, RMOD can also track the size distribution of the hemozoin crystals. We establish the relations between the magneto-optical signal, the mean parasite age and the median crystal size throughout one erythrocytic cycle of Plasmodium falciparum parasites, where the latter two are determined by optical and scanning electron microscopy, respectively. The significant correlation between the magneto-optical signal and the stage distribution of the parasites indicates that the RMOD method can be utilized for species-specific malaria diagnosis and for the quick assessment of drug efficacy.
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Affiliation(s)
- Ágnes Orbán
- Department of Physics, BME Budapest University of Technology and Economics, Budapest, 1111, Hungary.
| | - Jan-Jonas Schumacher
- Experimental Physics 5, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86159, Augsburg, Germany
| | - Szilvia Mucza
- Department of Physics, BME Budapest University of Technology and Economics, Budapest, 1111, Hungary
| | - Ana Strinic
- Experimental Physics 5, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86159, Augsburg, Germany
| | - Petra Molnár
- Malaria Research Laboratory, Institute of Enzymology, Research Centre for Natural Sciences, Budapest, 1117, Hungary
| | - Réka Babai
- Malaria Research Laboratory, Institute of Enzymology, Research Centre for Natural Sciences, Budapest, 1117, Hungary
- Department of Applied Biotechnology and Food Sciences, BME Budapest University of Technology and Economics, Budapest, 1111, Hungary
| | - András Halbritter
- Department of Physics, BME Budapest University of Technology and Economics, Budapest, 1111, Hungary
| | - Beáta G Vértessy
- Malaria Research Laboratory, Institute of Enzymology, Research Centre for Natural Sciences, Budapest, 1117, Hungary
- Department of Applied Biotechnology and Food Sciences, BME Budapest University of Technology and Economics, Budapest, 1111, Hungary
| | - Stephan Karl
- Vector-Borne Diseases Unit, PNG Institute of Medical Research, Madang, Madang Province, 511, Papua New Guinea
- Australian Institute of Tropical Health and Medicine, James Cook University, Smithfield, QLS, Australia
| | - Stephan Krohns
- Experimental Physics 5, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86159, Augsburg, Germany
| | - István Kézsmárki
- Experimental Physics 5, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86159, Augsburg, Germany.
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2
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Edgar RCS, Counihan NA, McGowan S, de Koning-Ward TF. Methods Used to Investigate the Plasmodium falciparum Digestive Vacuole. Front Cell Infect Microbiol 2022; 11:829823. [PMID: 35096663 PMCID: PMC8794586 DOI: 10.3389/fcimb.2021.829823] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 12/22/2021] [Indexed: 11/13/2022] Open
Abstract
Plasmodium falciparum malaria remains a global health problem as parasites continue to develop resistance to all antimalarials in use. Infection causes clinical symptoms during the intra-erythrocytic stage of the lifecycle where the parasite infects and replicates within red blood cells (RBC). During this stage, P. falciparum digests the main constituent of the RBC, hemoglobin, in a specialized acidic compartment termed the digestive vacuole (DV), a process essential for survival. Many therapeutics in use target one or multiple aspects of the DV, with chloroquine and its derivatives, as well as artemisinin, having mechanisms of action within this organelle. In order to better understand how current therapeutics and those under development target DV processes, techniques used to investigate the DV are paramount. This review outlines the involvement of the DV in therapeutics currently in use and focuses on the range of techniques that are currently utilized to study this organelle including microscopy, biochemical analysis, genetic approaches and metabolomic studies. Importantly, continued development and application of these techniques will aid in our understanding of the DV and in the development of new therapeutics or therapeutic partners for the future.
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Affiliation(s)
- Rebecca C. S. Edgar
- School of Medicine, Deakin University, Geelong, VIC, Australia
- The Institute for Mental and Physical Health and Clinical Translation, Deakin University, Geelong, VIC, Australia
| | - Natalie A. Counihan
- School of Medicine, Deakin University, Geelong, VIC, Australia
- The Institute for Mental and Physical Health and Clinical Translation, Deakin University, Geelong, VIC, Australia
| | - Sheena McGowan
- Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, VIC, Australia
- Centre to Impact AMR, Monash University, Monash University, Clayton, VIC, Australia
| | - Tania F. de Koning-Ward
- School of Medicine, Deakin University, Geelong, VIC, Australia
- The Institute for Mental and Physical Health and Clinical Translation, Deakin University, Geelong, VIC, Australia
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3
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Artemisinin-Based Drugs Target the Plasmodium falciparum Heme Detoxification Pathway. Antimicrob Agents Chemother 2021; 65:AAC.02137-20. [PMID: 33495226 DOI: 10.1128/aac.02137-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 01/16/2021] [Indexed: 12/18/2022] Open
Abstract
Artemisinin (ART)-based antimalarial drugs are believed to exert lethal effects on malarial parasites by alkylating a variety of intracellular molecular targets. Recent work with live parasites has shown that one of the alkylated targets is free heme within the parasite digestive vacuole, which is liberated upon hemoglobin catabolism by the intraerythrocytic parasite, and that reduced levels of heme alkylation occur in artemisinin-resistant parasites. One implication of heme alkylation is that these drugs may inhibit parasite detoxification of free heme via inhibition of heme-to-hemozoin crystallization; however, previous reports that have investigated this hypothesis present conflicting data. By controlling reducing conditions and, hence, the availability of ferrous versus ferric forms of free heme, we modify a previously reported hemozoin inhibition assay to quantify the ability of ART-based drugs to target the heme detoxification pathway under reduced versus oxidizing conditions. Contrary to some previous reports, we find that artemisinins are potent inhibitors of hemozoin crystallization, with effective half-maximal concentrations approximately an order of magnitude lower than those for most quinoline-based antimalarial drugs. We also examine hemozoin and in vitro parasite growth inhibition for drug pairs found in the most commonly used ART-based combination therapies (ACTs). All ACTs examined inhibit hemozoin crystallization in an additive fashion, and all but one inhibit parasite growth in an additive fashion.
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Heller LE, Roepe PD. Artemisinin-Based Antimalarial Drug Therapy: Molecular Pharmacology and Evolving Resistance. Trop Med Infect Dis 2019; 4:tropicalmed4020089. [PMID: 31167396 PMCID: PMC6631165 DOI: 10.3390/tropicalmed4020089] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 05/21/2019] [Accepted: 05/24/2019] [Indexed: 12/27/2022] Open
Abstract
The molecular pharmacology of artemisinin (ART)-based antimalarial drugs is incompletely understood. Clinically, these drugs are used in combination with longer lasting partner drugs in several different artemisinin combination therapies (ACTs). ACTs are currently the standard of care against Plasmodium falciparum malaria across much of the world. A harbinger of emerging artemisinin resistance (ARTR), known as the delayed clearance phenotype (DCP), has been well documented in South East Asia (SEA) and is beginning to affect the efficacy of some ACTs. Though several genetic mutations have been associated with ARTR/DCP, a molecular mechanism remains elusive. This paper summarizes our current understanding of ART molecular pharmacology and hypotheses for ARTR/DCP.
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Affiliation(s)
- Laura E Heller
- Departments of Chemistry and of Biochemistry and Cellular and Molecular Biology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, USA.
| | - Paul D Roepe
- Departments of Chemistry and of Biochemistry and Cellular and Molecular Biology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, USA.
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5
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Heller LE, Roepe PD. Quantification of Free Ferriprotoporphyrin IX Heme and Hemozoin for Artemisinin Sensitive versus Delayed Clearance Phenotype Plasmodium falciparum Malarial Parasites. Biochemistry 2018; 57:6927-6934. [PMID: 30513202 DOI: 10.1021/acs.biochem.8b00959] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We use Plasmodium falciparum culture synchronization, optimized heme and hemozoin extraction protocols, and mass spectrometry to quantify the abundance of free ferriprotoporphyrin IX (FPIX) heme and crystallized FPIX (hemozoin; Hz) for various growth stages of intraerythrocytic P. falciparum malarial parasites. Because of altered cell cycle kinetics for delayed clearance phenotype (DCP) parasites relative to that of the control, we test whether FPIX and Hz abundances differ for DCP and control parasites.
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Affiliation(s)
- Laura E Heller
- Department of Chemistry and Department of Biochemistry and Cellular and Molecular Biology , Georgetown University , 37th and O Streets Northwest , Washington, D.C. 20057 , United States
| | - Paul D Roepe
- Department of Chemistry and Department of Biochemistry and Cellular and Molecular Biology , Georgetown University , 37th and O Streets Northwest , Washington, D.C. 20057 , United States
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6
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Heller LE, Goggins E, Roepe PD. Dihydroartemisinin-Ferriprotoporphyrin IX Adduct Abundance in Plasmodium falciparum Malarial Parasites and the Relationship to Emerging Artemisinin Resistance. Biochemistry 2018; 57:6935-6945. [PMID: 30512926 DOI: 10.1021/acs.biochem.8b00960] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Previously (Heller, L. E., and Roepe, P. D. Quantification of Free Ferriprotoporphyrin IX Heme and Hemozoin for Artemisinin Sensitive versus Delayed Clearance Phenotype Plasmodium falciparum Malarial Parasites. Biochemistry, DOI: 10.1021/acs.biochem.8b00959, preceding paper in this issue), we quantified free ferriprotoporphyrin IX (FPIX) heme abundance for control versus delayed clearance phenotype (DCP) intraerythrocytic Plasmodium falciparum malarial parasites. Because artemisinin drugs are activated by free FPIX, these data predict that the abundance of long-hypothesized toxic artemisinin drug-FPIX covalent adducts might differ for control versus DCP parasites. If so, this would have important repercussions for understanding the mechanism of the DCP, also known as emerging artemisinin resistance. To test these predictions, we studied in vitro formation of FPIX-dihydroartemisinin (DHA) adducts and then for the first time quantified the abundance of FPIX-DHA adducts formed within live P. falciparum versus the stage of intraerythrocytic development. Using matched isogenic parasite strains, we quantified the adduct for DCP versus control parasite strains and found that mutant PfK13 mediates lower adduct abundance for DCP parasites. The results suggest improved models for the molecular pharmacology of artemisinin-based antimalarial drugs and the molecular mechanism of the DCP.
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Affiliation(s)
- Laura E Heller
- Department of Chemistry and Department of Biochemistry and Cellular and Molecular Biology , Georgetown University , 37th and O Streets Northwest , Washington, D.C. 20057 , United States
| | - Eibhlin Goggins
- Department of Chemistry and Department of Biochemistry and Cellular and Molecular Biology , Georgetown University , 37th and O Streets Northwest , Washington, D.C. 20057 , United States
| | - Paul D Roepe
- Department of Chemistry and Department of Biochemistry and Cellular and Molecular Biology , Georgetown University , 37th and O Streets Northwest , Washington, D.C. 20057 , United States
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7
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Ullah I, Sharma R, Biagini GA, Horrocks P. A validated bioluminescence-based assay for the rapid determination of the initial rate of kill for discovery antimalarials. J Antimicrob Chemother 2017; 72:717-726. [PMID: 27999014 DOI: 10.1093/jac/dkw449] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 09/22/2016] [Indexed: 11/13/2022] Open
Abstract
Objectives A future treatment for uncomplicated malaria will contain at least one component that exerts a rapid rate of kill. We describe here the validation and application of a simple, robust and rapid bioluminescence-based assay for the determination of the initial rate of kill in intra-erythrocytic asexual stages of Plasmodium falciparum . Methods A modification to the concentration-response bioluminescence [here termed bioluminescence relative rate of kill (BRRoK)] assay, utilizing exposure to fold-IC 50 concentrations (0.33× to 9×), was used to monitor the immediate cytocidal effect of 372 open-source compounds for antimalarial drug discovery available through the Medicines for Malaria Venture Malaria Box. Results Antimalarial drugs that exert a rapid cytocidal effect produce a concentration-dependent loss of bioluminescence signal that correlates with available in vitro and in vivo estimates of parasite clearance time and parasite reduction ratio. Following the measurement of IC 50 for the Malaria Box compounds in Dd2 luc , the BRRoK assay was used to identify and rank 372 compounds for their initial cytocidal activity. Fifty-three compounds in the Malaria Box show an initial relative rate of kill greater than that of chloroquine, with 17 of these having an initial relative rate of kill greater than that of dihydroartemisinin. Conclusions The BRRoK assay provides a rapid assay format for the estimation of a key pharmacodynamic property of antimalarial drug action. The simplicity and robustness of the assay suggests it would be readily scalable for high-throughput screening and a critical decision-making tool for antimalarial drug development.
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Affiliation(s)
- Imran Ullah
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
| | - Raman Sharma
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Giancarlo A Biagini
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Paul Horrocks
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
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8
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Pisciotta JM, Scholl PF, Shuman JL, Shualev V, Sullivan DJ. Quantitative characterization of hemozoin in Plasmodium berghei and vivax. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2017; 7:110-119. [PMID: 28279945 PMCID: PMC5342986 DOI: 10.1016/j.ijpddr.2017.02.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 02/01/2017] [Accepted: 02/03/2017] [Indexed: 12/21/2022]
Abstract
The incidence and global distribution of chloroquine resistant (CR) Plasmodium vivax infection has increased since emerging in 1989. The mechanism of resistance in CR P. vivax has not been defined. The resistance likely relates to the formation and disposition of hemozoin as chloroquine's primary mechanism of action involves disruption of hemozoin formation. CR P. berghei strains, like CR P. vivax strains, are confined to reticulocyte host cells and reportedly they do not accumulate appreciable intraerythrocytic hemozoin. Reports comparing hemozoin production between P. vivax strains and CR to chloroquine sensitive (CS) P. berghei are absent. Here we compare in vivo patterns of hemozoin formation and distribution in blood, spleen and liver tissue of male Swiss mice infected with CS or CR P. berghei not treated with chloroquine and CR P. berghei also treated with chloroquine. Light microscopy, laser desorption mass spectrometry and a colorimetric hemozoin assay detect trace hemozoin in the blood of CR P. berghei infected mice but significant hemozoin accumulation in liver and spleen tissue. Field emission in lens scanning electron microscopy reveals CR P. berghei hemozoin crystals are morphologically smaller but similar to those formed by CS parasites. CR P. berghei produces approximately five-fold less total hemozoin than CS strain. Lipid analysis of CS and CR P. berghei sucrose gradient purified bloodstage hemozoin indicates a similar lipid environment around the isolated hemozoin, predominately monopalmitic glycerol and monostearic glycerol. In contrast to CR and CS P. berghei, colorimetric hemozoin analysis of P. vivax strains indicates similar amounts of hemozoin are produced despite differing chloroquine sensitivities. These results suggest CR P. berghei forms significant hemozoin which accumulates in liver and spleen tissues and that the P. vivax chloroquine resistance mechanism differs from P. berghei. Chloroquine resistant Plasmodium berghei release measurable hemozoin into tissues with blood hemozoin 100 times less per parasite while total in all tissues is only 5 times less than chloroquine sensitive. Chloroquine resistant P. bergheihemozoin crystals are morphologically smaller but similar to those formed by chloroquine sensitive parasites. Chloroquine resistance in P. vivax is distinct from P. berghei even though both infect reticulocytes.
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Affiliation(s)
- John M Pisciotta
- Department of Molecular Microbiology and Immunology, Johns Hopkins University, Bloomberg School of Public Health, 615 N. Wolfe St., Baltimore, MD 21205-2179, USA
| | - Peter F Scholl
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205-2103, USA
| | - Joel L Shuman
- Virginia Bioinformatics Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| | - Vladimir Shualev
- Virginia Bioinformatics Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| | - David J Sullivan
- Department of Molecular Microbiology and Immunology, Johns Hopkins University, Bloomberg School of Public Health, 615 N. Wolfe St., Baltimore, MD 21205-2179, USA.
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Endoperoxide Drug Cross-Resistance Patterns for Plasmodium falciparum Exhibiting an Artemisinin Delayed-Clearance Phenotype. Antimicrob Agents Chemother 2016; 60:6952-6956. [PMID: 27600038 DOI: 10.1128/aac.00857-16] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 08/28/2016] [Indexed: 11/20/2022] Open
Abstract
The ring-stage susceptibility assay was modified to quantify the susceptibilities of multiple strains of control and delayed-clearance phenotype (DCP) Plasmodium falciparum strains to seven endoperoxide antimalarial drugs. The susceptibility of all of the DCP lines to six of the drugs was lower than that of the controls. In contrast, DCP parasites did not show reduced susceptibility to the synthetic endoperoxide drug OZ439. These data show that it is possible to circumvent emerging artemisinin resistance with a modified endoperoxide drug.
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10
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Towards ultrasensitive malaria diagnosis using surface enhanced Raman spectroscopy. Sci Rep 2016; 6:20177. [PMID: 26858127 PMCID: PMC4746575 DOI: 10.1038/srep20177] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 12/23/2015] [Indexed: 01/03/2023] Open
Abstract
We report two methods of surface enhanced Raman spectroscopy (SERS) for hemozoin detection in malaria infected human blood. In the first method, silver nanoparticles were synthesized separately and then mixed with lysed blood; while in the second method, silver nanoparticles were synthesized directly inside the parasites of Plasmodium falciparum. It was observed that the first method yields a smaller variation in SERS measurements and stronger correlation between the estimated contribution of hemozoin and the parasitemia level, which is preferred for the quantification of the parasitemia level. In contrast, the second method yields a higher sensitivity to a low parasitemia level thus could be more effective in the early malaria diagnosis to determine whether a given blood sample is positive.
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Eom J, Gong J, Kwon S, Jeon A, Jeong R, Driver RW, Lee H. A Hollow Foldecture with Truncated Trigonal Bipyramid Shape from the Self‐Assembly of an 11‐Helical Foldamer. Angew Chem Int Ed Engl 2015; 54:13204-7. [DOI: 10.1002/anie.201504248] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 07/13/2015] [Indexed: 01/20/2023]
Affiliation(s)
- Jae‐Hoon Eom
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Jintaek Gong
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Sunbum Kwon
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Aram Jeon
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Rokam Jeong
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Russell W. Driver
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Hee‐Seung Lee
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
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12
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Eom J, Gong J, Kwon S, Jeon A, Jeong R, Driver RW, Lee H. A Hollow Foldecture with Truncated Trigonal Bipyramid Shape from the Self‐Assembly of an 11‐Helical Foldamer. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201504248] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jae‐Hoon Eom
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Jintaek Gong
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Sunbum Kwon
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Aram Jeon
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Rokam Jeong
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Russell W. Driver
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
| | - Hee‐Seung Lee
- Department of Chemistry, KAIST, Molecular‐Level Interface Research Center, 291 Daehak‐ro, Yuseong‐gu, Daejeon 305‐701 (Korea) http://hslee.kaist.ac.kr
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13
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Azouzi S, El Kirat K, Morandat S. Hematin loses its membranotropic activity upon oligomerization into malaria pigment. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:2952-9. [PMID: 26296297 DOI: 10.1016/j.bbamem.2015.08.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 08/05/2015] [Accepted: 08/16/2015] [Indexed: 11/24/2022]
Abstract
Malaria is an infectious disease caused by Plasmodium type parasites transmitted by the bites of infected female anopheles mosquitoes. The malaria parasite multiplies in red blood cells where it degrades hemoglobin. This degradation of hemoglobin proteins releases hematin, an iron-containing porphyrin, which provokes membrane disruption and lysis. The malaria parasite blocks hematin-induced lysis by biocrystallization, a process that converts hematin into insoluble and chemically inert crystals. Hematin molecules are especially prone to self-assembly as dimers, oligomers and aggregates depending on environmental conditions (pH, solvent, temperature, concentration, ionic strength). Considering the different forms of hematin-based assemblies, it is still unclear which are the ones able to interact with membranes. We have prepared hematin under different conditions to form hematin-based assemblies and to measure their ability to interact and to disorganize membranes. Our results show that different forms of hematin molecules are able to penetrate lipid membranes. Interestingly, this membrane activity is spontaneously inhibited at acidic pH and it can be restored under neutral pH. By contrast, the oligomers of β-hematin were found to be completely harmless toward lipid membranes. Finally, the AFM visualization of hematin interaction with supported lipid bilayers showed for the first time its preferential interaction with defaults in membranes, at the boundaries between two distinct lipid phases. The superficial adsorption of aggregates on membranes and the absence of effect due to oligomers were also confirmed with AFM.
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Affiliation(s)
- Slim Azouzi
- Laboratoire d'excellence GR-Ex, Inserm S1134, Université Paris-Diderot, Institut National de la Transfusion Sanguine, 6, rue Alexandre Cabanel, 75739 Paris cedex 15, France
| | - Karim El Kirat
- Sorbonne universités, Université de technologie de Compiègne, CNRS, Laboratoire de BioMécanique et BioIngénierie UMR 7338, Centre de recherche Royallieu, CS 60 319, 60 203 Compiègne cedex, France
| | - Sandrine Morandat
- Sorbonne universités, Université de technologie de Compiègne, CNRS, Laboratoire de Génie Enzymatique et Cellulaire FRE 3580, Centre de recherche Royallieu, CS 60 319, 60 203 Compiègne cedex, France.
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14
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Schnermann MJ, Shenvi RA. Syntheses and biological studies of marine terpenoids derived from inorganic cyanide. Nat Prod Rep 2015; 32:543-77. [PMID: 25514696 DOI: 10.1039/c4np00109e] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Isocyanoterpenes (ICTs) are marine natural products biosynthesized through an unusual pathway that adorns terpene scaffolds with nitrogenous functionality derived from cyanide. The appendage of nitrogen functional groups - isonitriles in particular - onto stereochemically-rich carbocyclic ring systems provides enigmatic, bioactive molecules that have required innovative chemical syntheses. This review discusses the challenges inherent to the synthesis of this diverse family and details the development of the field. We also present recent progress in isolation and discuss key aspects of the remarkable biological activity of these compounds.
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Affiliation(s)
- Martin J Schnermann
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21701, USA.
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15
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Paulo A, Figueiras M, Machado M, Charneira C, Lavrado J, Santos SA, Lopes D, Gut J, Rosenthal PJ, Nogueira F, Moreira R. Bis-alkylamine Indolo[3,2-b]quinolines as Hemozoin Ligands: Implications for Antimalarial Cytostatic and Cytocidal Activities. J Med Chem 2014; 57:3295-313. [DOI: 10.1021/jm500075d] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Alexandra Paulo
- Instituto
de Investigação do Medicamento (iMed.ULisboa), Faculdade
de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Marta Figueiras
- Instituto
de Investigação do Medicamento (iMed.ULisboa), Faculdade
de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Marta Machado
- UEI
Malaria, Centro da Malária e Doenças Tropicais, IHMT, Universidade Nova de Lisboa, Rua da Junqueira, 100, P-1349-008 Lisboa, Portugal
| | - Catarina Charneira
- Instituto
de Investigação do Medicamento (iMed.ULisboa), Faculdade
de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - João Lavrado
- Instituto
de Investigação do Medicamento (iMed.ULisboa), Faculdade
de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Sofia A. Santos
- Instituto
de Investigação do Medicamento (iMed.ULisboa), Faculdade
de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Dinora Lopes
- UEI
Malaria, Centro da Malária e Doenças Tropicais, IHMT, Universidade Nova de Lisboa, Rua da Junqueira, 100, P-1349-008 Lisboa, Portugal
| | - Jiri Gut
- Department
of Medicine, San Francisco General Hospital, University of California, San Francisco, Box 0811, San Francisco, California 94143, United States
| | - Philip J. Rosenthal
- Department
of Medicine, San Francisco General Hospital, University of California, San Francisco, Box 0811, San Francisco, California 94143, United States
| | - Fátima Nogueira
- UEI
Malaria, Centro da Malária e Doenças Tropicais, IHMT, Universidade Nova de Lisboa, Rua da Junqueira, 100, P-1349-008 Lisboa, Portugal
| | - Rui Moreira
- Instituto
de Investigação do Medicamento (iMed.ULisboa), Faculdade
de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
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16
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Kim K, Yoon H, Diez-Silva M, Dao M, Dasari RR, Park Y. High-resolution three-dimensional imaging of red blood cells parasitized by Plasmodium falciparum and in situ hemozoin crystals using optical diffraction tomography. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:011005. [PMID: 23797986 PMCID: PMC4019420 DOI: 10.1117/1.jbo.19.1.011005] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2013] [Revised: 05/06/2013] [Accepted: 05/29/2013] [Indexed: 05/18/2023]
Abstract
We present high-resolution optical tomographic images of human red blood cells (RBC) parasitized by malaria-inducing Plasmodium falciparum (Pf)-RBCs. Three-dimensional (3-D) refractive index (RI) tomograms are reconstructed by recourse to a diffraction algorithm from multiple two-dimensional holograms with various angles of illumination. These 3-D RI tomograms of Pf-RBCs show cellular and subcellular structures of host RBCs and invaded parasites in fine detail. Full asexual intraerythrocytic stages of parasite maturation (ring to trophozoite to schizont stages) are then systematically investigated using optical diffraction tomography algorithms. These analyses provide quantitative information on the structural and chemical characteristics of individual host Pf-RBCs, parasitophorous vacuole, and cytoplasm. The in situ structural evolution and chemical characteristics of subcellular hemozoin crystals are also elucidated.
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Affiliation(s)
- Kyoohyun Kim
- Korea Advanced Institute of Science and Technology, Department of Physics, Daejeon 305-701, Republic of Korea
| | - HyeOk Yoon
- Korea Advanced Institute of Science and Technology, Department of Physics, Daejeon 305-701, Republic of Korea
| | - Monica Diez-Silva
- Massachusetts Institute of Technology, Department of Material Science and Engineering, Cambridge, Massachusetts 02142
| | - Ming Dao
- Massachusetts Institute of Technology, Department of Material Science and Engineering, Cambridge, Massachusetts 02142
| | - Ramachandra R. Dasari
- Massachusetts Institute of Technology, George R. Harrison Spectroscopy Laboratory, Cambridge, Massachusetts 02194
| | - YongKeun Park
- Korea Advanced Institute of Science and Technology, Department of Physics, Daejeon 305-701, Republic of Korea
- Address all correspondence to: YongKeun Park, Korea Advanced Institute of Science and Technology, Department of Physics, 291 Daehak-Ro Yusung-Gu, Daejeon 305-701, Republic of Korea. Tel: (82) 42-350-2514; Fax: (82) 42-350-7160; E-mail:
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17
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Tyberghein A, Deroost K, Schwarzer E, Arese P, Van den Steen PE. Immunopathological effects of malaria pigment or hemozoin and other crystals. Biofactors 2014; 40:59-78. [PMID: 23907956 DOI: 10.1002/biof.1119] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 05/01/2013] [Accepted: 05/07/2013] [Indexed: 01/26/2023]
Abstract
Blood-stage malaria parasites produce insoluble hemozoin (Hz) crystals that are released in the blood circulation upon schizont rupture. In general, endogenous crystal formation or inhalation of crystalline materials is often associated with pathology. As the immune system responds differently to crystalline particles than to soluble molecules, in this review, the properties, immunological recognition, and pathogenic responses of Hz are discussed, and compared with two other major pathogenic crystals, monosodium urate (MSU) and asbestos. Because of the size and shape of MSU crystals and asbestos fibers, phagolysosomal formation is inefficient and often results in leakage of lysosomal content in the cell cytoplasm and/or in the extracellular environment with subsequent cell damage and cell death. Phagolysosomal formation after Hz ingestion is normal, but Hz remains stored inside these cells for months or even longer without any detectable degradation. Nonetheless, the different types of crystals are recognized by similar immune receptors, involving Toll-like receptors, the inflammasome, antibodies, and/or complement factors, and through similar signaling cascades, they activate both proinflammatory and anti-inflammatory immune responses that contribute to inflammation-associated pathology.
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Affiliation(s)
- Ariane Tyberghein
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, Leuven, Belgium
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18
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A process similar to autophagy is associated with cytocidal chloroquine resistance in Plasmodium falciparum. PLoS One 2013; 8:e79059. [PMID: 24278114 PMCID: PMC3835802 DOI: 10.1371/journal.pone.0079059] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 09/24/2013] [Indexed: 12/31/2022] Open
Abstract
Resistance to the cytostatic activity of the antimalarial drug chloroquine (CQ) is becoming well understood, however, resistance to cytocidal effects of CQ is largely unexplored. We find that PfCRT mutations that almost fully recapitulate P. falciparum cytostatic CQ resistance (CQRCS) as quantified by CQ IC50 shift, account for only 10–20% of cytocidal CQR (CQRCC) as quantified by CQ LD50 shift. Quantitative trait loci (QTL) analysis of the progeny of a chloroquine sensitive (CQS; strain HB3)×chloroquine resistant (CQR; strain Dd2) genetic cross identifies distinct genetic architectures for CQRCS vs CQRCC phenotypes, including identification of novel interacting chromosomal loci that influence CQ LD50. Candidate genes in these loci are consistent with a role for autophagy in CQRCC, leading us to directly examine the autophagy pathway in intraerythrocytic CQR parasites. Indirect immunofluorescence of RBC infected with synchronized CQS vs CQR trophozoite stage parasites reveals differences in the distribution of the autophagy marker protein PfATG8 coinciding with CQRCC. Taken together, the data show that an unusual autophagy – like process is either activated or inhibited for intraerythrocytic trophozoite parasites at LD50 doses (but not IC50 doses) of CQ, that the pathway is altered in CQR P. falciparum, and that it may contribute along with mutations in PfCRT to confer the CQRCC phenotype.
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19
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Egan TJ, Kuter D. Dual-functioning antimalarials that inhibit the chloroquine-resistance transporter. Future Microbiol 2013; 8:475-89. [PMID: 23534360 PMCID: PMC7099626 DOI: 10.2217/fmb.13.18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Malaria remains a major international health challenge. Resistance to a number of existing drugs and evidence of the emergence of artemisinin resistance has emphasized the need for new antimalarials. A new approach has been the preparation of dual-function compounds that include a chloroquine-like antimalarial group and a group that resembles a chloroquine chemosensitizer. This article reviews the recent discovery of such dual-function antimalarials that are proposed to target both hemozoin formation and the chloroquine resistance transporter, PfCRT. These are discussed in relation to the mechanism of action of 4-aminoquinolines, chloroquine resistance and resistance reversal.
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Affiliation(s)
- Timothy J Egan
- Department of Chemistry, University of Cape Town, Private Bag, Rondebosch 7701, South Africa.
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20
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Gorka AP, de Dios A, Roepe PD. Quinoline drug-heme interactions and implications for antimalarial cytostatic versus cytocidal activities. J Med Chem 2013; 56:5231-46. [PMID: 23586757 DOI: 10.1021/jm400282d] [Citation(s) in RCA: 132] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Historically, the most successful molecular target for antimalarial drugs has been heme biomineralization within the malarial parasite digestive vacuole. Heme released from catabolized host red blood cell hemoglobin is toxic, so malarial parasites crystallize heme to nontoxic hemozoin. For years it has been accepted that a number of effective quinoline antimalarial drugs (e.g., chloroquine, quinine, amodiaquine) function by preventing hemozoin crystallization. However, recent studies over the past decade have revealed a surprising molecular diversity in quinoline-heme molecular interactions. This diversity shows that even closely related quinoline drugs may have quite different molecular pharmacology. This paper reviews the molecular diversity and highlights important implications for understanding quinoline antimalarial drug resistance and for future drug design.
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Affiliation(s)
- Alexander P Gorka
- Department of Chemistry, Department of Biochemistry, Cellular, and Molecular Biology, and Center for Infectious Diseases, Georgetown University , 37th and O Streets, NW, Washington, D.C. 20057, United States
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21
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Affiliation(s)
- Paloma F. Salas
- Medicinal Inorganic Chemistry
Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia
V6T 1Z1, Canada
| | - Christoph Herrmann
- Medicinal Inorganic Chemistry
Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia
V6T 1Z1, Canada
- Advanced
Applied Physics Solutions, TRIUMF, 4004
Wesbrook Mall, Vancouver, British Columbia
V6T 2A3, Canada
| | - Chris Orvig
- Medicinal Inorganic Chemistry
Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia
V6T 1Z1, Canada
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22
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Lehane AM, McDevitt CA, Kirk K, Fidock DA. Degrees of chloroquine resistance in Plasmodium - is the redox system involved? INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2012; 2:47-57. [PMID: 22773965 DOI: 10.1016/j.ijpddr.2011.11.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Chloroquine (CQ) was once a very effective antimalarial drug that, at its peak, was consumed in the hundreds of millions of doses per year. The drug acts against the Plasmodium parasite during the asexual intraerythrocytic phase of its lifecycle. Unfortunately, clinical resistance to this drug is now widespread. Questions remain about precisely how CQ kills malaria parasites, and by what means some CQ-resistant (CQR) parasites can withstand much higher concentrations of the drug than others that also fall in the CQR category. In this review we investigate the evidence for and against the proposal that CQ kills parasites by generating oxidative stress. Further, we examine a long-held idea that the glutathione system of malaria parasites plays a role in CQ resistance. We conclude that there is strong evidence that glutathione levels modulate CQ response in the rodent malaria species P. berghei, but that a role for redox in contributing to the degree of CQ resistance in species infectious to humans has not been firmly established.
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Affiliation(s)
- Adele M Lehane
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY 10032, USA
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23
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Herrmann C, Salas PF, Cawthray JF, de Kock C, Patrick BO, Smith PJ, Adam MJ, Orvig C. 1,1′-Disubstituted Ferrocenyl Carbohydrate Chloroquine Conjugates as Potential Antimalarials. Organometallics 2012. [DOI: 10.1021/om300354x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Christoph Herrmann
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British
Columbia V6T 1Z1, Canada
- Advanced Applied Physics Solutions, 4004
Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - Paloma F. Salas
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British
Columbia V6T 1Z1, Canada
| | - Jacqueline F. Cawthray
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British
Columbia V6T 1Z1, Canada
- TRIUMF,
4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - Carmen de Kock
- Department of Medicine, University of Cape Town Medical School, Observatory 7925, South Africa
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Brian O. Patrick
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British
Columbia V6T 1Z1, Canada
| | - Peter J. Smith
- Department of Medicine, University of Cape Town Medical School, Observatory 7925, South Africa
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Michael J. Adam
- TRIUMF,
4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - Chris Orvig
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British
Columbia V6T 1Z1, Canada
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24
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Kim J, Massoudi M, Antaki JF, Gandini A. Removal of malaria-infected red blood cells using magnetic cell separators: A computational study. APPLIED MATHEMATICS AND COMPUTATION 2012; 218:6841-6850. [PMID: 22345827 PMCID: PMC3278042 DOI: 10.1016/j.amc.2011.12.057] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
High gradient magnetic field separators have been widely used in a variety of biological applications. Recently, the use of magnetic separators to remove malaria-infected red blood cells (pRBCs) from blood circulation in patients with severe malaria has been proposed in a dialysis-like treatment. The capture efficiency of this process depends on many interrelated design variables and constraints such as magnetic pole array pitch, chamber height, and flow rate. In this paper, we model the malaria-infected RBCs (pRBCs) as paramagnetic particles suspended in a Newtonian fluid. Trajectories of the infected cells are numerically calculated inside a micro-channel exposed to a periodic magnetic field gradient. First-order stiff ordinary differential equations (ODEs) governing the trajectory of particles under periodic magnetic fields due to an array of wires are solved numerically using the 1(st) -5(th) order adaptive step Runge-Kutta solver. The numerical experiments show that in order to achieve a capture efficiency of 99% for the pRBCs it is required to have a longer length than 80 mm; this implies that in principle, using optimization techniques the length could be adjusted, i.e., shortened to achieve 99% capture efficiency of the pRBCs.
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Affiliation(s)
- Jeongho Kim
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213 USA
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25
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O'Cualain RDM, Hyde JE, Sims PFG. A protein-centric approach for the identification of folate enzymes from the malarial parasite, Plasmodium falciparum, using OFFGEL™ solution-based isoelectric focussing and mass spectrometry. Malar J 2010; 9:286. [PMID: 20955557 PMCID: PMC2967559 DOI: 10.1186/1475-2875-9-286] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Accepted: 10/18/2010] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Plasmodium species are difficult to study using proteomic technology because they contain large amounts of haemoglobin-derived products (HDP), generated by parasite breakdown of host haemoglobin. HDP are known to interfere with isoelectric focussing, a cornerstone of fractionation strategies for the identification of proteins by mass spectrometry. In addition to the challenge presented by this material, as in most proteomes, there exists in this parasite a considerable dynamic range between proteins of high and low abundance. The enzymes of the folate pathway, a proven and widely used drug target, are included in the latter class. METHODS This report describes a work-flow utilizing a parasite-specific extraction protocol that minimizes release of HDP into the lysate, followed by in-solution based OFFGEL™ electrophoresis at the protein level, trypsin digestion and mass spectrometric analysis. RESULTS It is demonstrated that, by removing HDP from parasite lysates, OFFGEL™-mediated protein separation is able to deliver reduced complexity protein fractions. Importantly, proteins with similar and predictable physical properties are sharply focussed within such fractions. CONCLUSIONS By following this novel workflow, data have been obtained which allow the unequivocal experimental identification by mass spectrometry of four of the six proteins involved in folate biosynthesis and recycling.
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Affiliation(s)
- Ronan DM O'Cualain
- Manchester Interdisciplinary Biocentre, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - John E Hyde
- Manchester Interdisciplinary Biocentre, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - Paul FG Sims
- Manchester Interdisciplinary Biocentre, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
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26
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Pleeter P, Lekostaj JK, Roepe PD. Purified Plasmodium falciparum multi-drug resistance protein (PfMDR 1) binds a high affinity chloroquine analogue. Mol Biochem Parasitol 2010; 173:158-61. [PMID: 20546803 DOI: 10.1016/j.molbiopara.2010.05.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Revised: 05/13/2010] [Accepted: 05/14/2010] [Indexed: 11/16/2022]
Abstract
We utilize the recent successful overexpression of recombinant Plasmodium falciparum multi-drug resistance transporter, purification and reconstitution of the protein, and a novel high affinity chloroquine analogue to probe hypothesized interaction between the transporter and quinoline drugs. Results suggest that PfMDR1 binding sites for chloroquine, mefloquine, and quinine overlap, that P. falciparum chloroquine resistance transporter has intrinsically higher affinity for chloroquine relative to P. falciparum multi-drug resistance transporter, and that there is an isoform specific competition between the two transporters for binding of quinoline antimalarial drugs.
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Affiliation(s)
- Perri Pleeter
- Department of Chemistry, Georgetown University, 37th and O Streets, Washington, DC 20057, USA
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27
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Coppens I, Sullivan DJ, Prigge ST. An update on the rapid advances in malaria parasite cell biology. Trends Parasitol 2010; 26:305-10. [PMID: 20382563 DOI: 10.1016/j.pt.2010.03.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Revised: 03/10/2010] [Accepted: 03/12/2010] [Indexed: 01/05/2023]
Abstract
Recent years have seen rapid advances in our understanding of malaria parasite cell biology. Some of this progress has been the result of developments in genetic techniques, advances in imaging technology, and new molecular tools. We focus on three aspects of parasite cell biology: (i) plastid metabolism, (ii) sporozoite biology, and (iii) protein transport to and from the host erythrocyte. In each case recent work has led to a deeper understanding of parasite biology, often at the expense of previously accepted paradigms. These studies also highlight the impediments, technical and otherwise, that will have to be overcome for continued rapid progress in these fields.
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Affiliation(s)
- Isabelle Coppens
- Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
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28
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Cabrera M, Natarajan J, Paguio MF, Wolf C, Urbach JS, Roepe PD. Chloroquine transport in Plasmodium falciparum. 1. Influx and efflux kinetics for live trophozoite parasites using a novel fluorescent chloroquine probe. Biochemistry 2009; 48:9471-81. [PMID: 19728740 DOI: 10.1021/bi901034r] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Several models for how amino acid substitutions in the Plasmodium falciparum chloroquine resistance transporter (PfCRT) confer resistance to chloroquine (CQ) and other antimalarial drugs have been proposed. Distinguishing between these models requires detailed analysis of high-resolution CQ transport data that is unfortunately impossible to obtain with traditional radio-tracer methods. Thus, we have designed and synthesized fluorescent CQ analogues for drug transport studies. One probe places a NBD (6-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)hexanoic acid) group at the tertiary aliphatic N of CQ, via a flexible 6 C amide linker. This probe localizes to the malarial parasite digestive vacuole (DV) during initial perfusion under physiologic conditions and exhibits similar pharmacology relative to CQ, vs both CQ-sensitive (CQS) and CQ-resistant (CQR) parasites. Using live, synchronized intraerythrocytic parasites under continuous perfusion, we define NBD-CQ influx and efflux kinetics for CQS vs CQR parasites. Since this fluorescence approach provides data at much higher kinetic resolution relative to fast-filtration methods using (3)H-CQ, rate constants vs linear initial rates for CQ probe flux can be analyzed in detail. Importantly, we find that CQR parasites have a decreased rate constant for CQ influx into the DV and that this is due to mutation of PfCRT. Analysis of zero trans efflux for CQS and CQR parasites suggests that distinguishing between bound vs free pools of intra-DV drug probe is essential for proper kinetic analysis of efflux. The accompanying paper (DOI 10.1021/bi901035j ) further probes efflux kinetics for proteoliposomes containing purified, reconstituted PfCRT.
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Affiliation(s)
- Mynthia Cabrera
- Department of Chemistry, Georgetown University, NW, Washington, DC 20057, USA
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29
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Roepe PD. Molecular and physiologic basis of quinoline drug resistance in Plasmodium falciparum malaria. Future Microbiol 2009; 4:441-55. [PMID: 19416013 PMCID: PMC2724744 DOI: 10.2217/fmb.09.15] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
30 years before the discovery of the pfcrt gene, altered cellular drug accumulation in drug-resistant malarial parasites had been well documented. Heme released from catabolized hemoglobin was thought to be a key target for quinoline drugs, and additional modifications to quinoline drug structure in order to improve activity against chloroquine-resistant malaria were performed in a few laboratories. However, parasite cell culture methods were still in their infancy, assays for drug susceptibility were not well standardized, and the power of malarial genetics was decades away. The last 10 years have witnessed explosive progress in elucidation of the biochemistry of chloroquine resistance. This review briefly summarizes that progress, and discusses where additional work is needed.
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Affiliation(s)
- Paul D Roepe
- Department of Chemistry and Department of Biochemistry, Cellular & Molecular Biology, and Center for Infectious Disease, Georgetown University, Washington, DC 20057, USA.
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30
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Witola WH, El Bissati K, Pessi G, Xie C, Roepe PD, Mamoun CB. Disruption of the Plasmodium falciparum PfPMT gene results in a complete loss of phosphatidylcholine biosynthesis via the serine-decarboxylase-phosphoethanolamine-methyltransferase pathway and severe growth and survival defects. J Biol Chem 2008; 283:27636-27643. [PMID: 18694927 PMCID: PMC2562060 DOI: 10.1074/jbc.m804360200] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2008] [Revised: 07/24/2008] [Indexed: 11/06/2022] Open
Abstract
Biochemical studies in the human malaria parasite, Plasmodium falciparum, indicated that in addition to the pathway for synthesis of phosphatidylcholine from choline (CDP-choline pathway), the parasite synthesizes this major membrane phospholipid via an alternative pathway named the serine-decarboxylase-phosphoethanolamine-methyltransferase (SDPM) pathway using host serine and ethanolamine as precursors. However, the role the transmethylation of phosphatidylethanolamine plays in the biosynthesis of phosphatidylcholine and the importance of the SDPM pathway in the parasite's growth and survival remain unknown. Here, we provide genetic evidence that knock-out of the PfPMT gene encoding the phosphoethanolamine methyltransferase enzyme completely abrogates the biosynthesis of phosphatidylcholine via the SDPM pathway. Lipid analysis in knock-out parasites revealed that unlike in mammalian and yeast cells, methylation of phosphatidylethanolamine to phosphatidylcholine does not occur in P. falciparum, thus making the SDPM and CDP-choline pathways the only routes for phosphatidylcholine biosynthesis in this organism. Interestingly, loss of PfPMT resulted in significant defects in parasite growth, multiplication, and viability, suggesting that this gene plays an important role in the pathogenesis of intraerythrocytic Plasmodium parasites.
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Affiliation(s)
- William Harold Witola
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, Connecticut 06030
| | - Kamal El Bissati
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, Connecticut 06030
| | - Gabriella Pessi
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, Connecticut 06030
| | - Changan Xie
- Department of Chemistry and Department of Biochemistry, Cellular and Molecular Biology, Georgetown University, Washington, D. C. 20057
| | - Paul D Roepe
- Department of Chemistry and Department of Biochemistry, Cellular and Molecular Biology, Georgetown University, Washington, D. C. 20057
| | - Choukri Ben Mamoun
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, Connecticut 06030.
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31
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McAllister RG, Sisan DR, Urbach JS. Design and optimization of a high-speed, high-sensitivity, spinning disk confocal microscopy system. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:054058. [PMID: 19021437 DOI: 10.1117/1.2992141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We describe the principles, design, and systems integration of a flexible, high-speed, high-sensitivity, high-resolution confocal spinning disk microscopy (SDCM) system. We present several artifacts unique to high-speed SDCM along with techniques to minimize them. We show example experimental results from a specific implementation capable of generating 3-D image stacks containing 30 2-D slices at 30 stacks per second. This implementation also includes optics for differential interference contrast (DIC), phase, and bright-field imaging, as well as an optical trap with sensitive force and position measurement.
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Affiliation(s)
- Ryan G McAllister
- Georgetown University, Department of Physics, Washington, DC 20057, USA.
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Lazarus MD, Schneider TG, Taraschi TF. A new model for hemoglobin ingestion and transport by the human malaria parasite Plasmodium falciparum. J Cell Sci 2008; 121:1937-49. [PMID: 18477610 PMCID: PMC5105679 DOI: 10.1242/jcs.023150] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The current model for hemoglobin ingestion and transport by intraerythrocytic Plasmodium falciparum malaria parasites shares similarities with endocytosis. However, the model is largely hypothetical, and the mechanisms responsible for the ingestion and transport of host cell hemoglobin to the lysosome-like food vacuole (FV) of the parasite are poorly understood. Because actin dynamics play key roles in vesicle formation and transport in endocytosis, we used the actin-perturbing agents jasplakinolide and cytochalasin D to investigate the role of parasite actin in hemoglobin ingestion and transport to the FV. In addition, we tested the current hemoglobin trafficking model through extensive analysis of serial thin sections of parasitized erythrocytes (PE) by electron microscopy. We find that actin dynamics play multiple, important roles in the hemoglobin transport pathway, and that hemoglobin delivery to the FV via the cytostomes might be required for parasite survival. Evidence is provided for a new model, in which hemoglobin transport to the FV occurs by a vesicle-independent process.
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Affiliation(s)
- Michelle D. Lazarus
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Timothy G. Schneider
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Theodore F. Taraschi
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Egan TJ. Recent advances in understanding the mechanism of hemozoin (malaria pigment) formation. J Inorg Biochem 2008; 102:1288-99. [DOI: 10.1016/j.jinorgbio.2007.12.004] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 10/19/2007] [Accepted: 10/31/2007] [Indexed: 11/15/2022]
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Haemozoin formation. Mol Biochem Parasitol 2008; 157:127-36. [DOI: 10.1016/j.molbiopara.2007.11.005] [Citation(s) in RCA: 151] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 11/05/2007] [Accepted: 11/06/2007] [Indexed: 11/18/2022]
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Sanchez CP, Stein WD, Lanzer M. Dissecting the components of quinine accumulation in Plasmodium falciparum. Mol Microbiol 2008; 67:1081-93. [PMID: 18194156 DOI: 10.1111/j.1365-2958.2008.06108.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Although quinine, the active ingredient of chinchona bark, has been used in the treatment of malaria for several centuries, there is little information regarding the interactions of this drug with the human malaria parasite Plasmodium falciparum. To better understand quinine's mode of action and the mechanism underpinning reduced responsiveness, we have investigated the factors that contribute to quinine accumulation by parasites that differ in their susceptibility to quinine. Interestingly, passive distribution, in accordance with the intracellular pH gradients, and intracellular binding could account for only a small fraction of the high amount of quinine accumulated by the parasites investigated. The results of trans-stimulation kinetics suggest that high accumulation of quinine is brought about by a carrier-mediated import system. This import system seems to be weakened in parasites with reduced quinine susceptibility. Other data show that polymorphisms within PfCRT are causatively linked with an increased verapamil-sensitive quinine efflux that, depending on the genetic background, resulted in reduced quinine accumulation. The polymorphisms within PfMDR1 investigated did not affect quinine accumulation. Our data are consistent with the model that several factors, including acidotropic trapping, binding to intracellular sites and carrier-mediated import and export transport systems, contribute to steady-state intracellular quinine accumulation.
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Affiliation(s)
- Cecilia P Sanchez
- Hygiene Institut, Abteilung Parasitologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
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Gligorijevic B, Purdy K, Elliott DA, Cooper RA, Roepe PD. Stage independent chloroquine resistance and chloroquine toxicity revealed via spinning disk confocal microscopy. Mol Biochem Parasitol 2008; 159:7-23. [PMID: 18281110 DOI: 10.1016/j.molbiopara.2007.12.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Revised: 12/14/2007] [Accepted: 12/19/2007] [Indexed: 10/22/2022]
Abstract
We previously customized a Nipkow spinning disk confocal microscope (SDCM) to acquire 4D data for live, intraerythrocytic malarial parasites [Gligorijevic B, McAllister R, Urbach JS, Roepe, PD. Spinning disk confocal microscopy of live, intraerythrocytic malarial parasites. 1. Quantification of hemozoin development for drug sensitive versus resistant malaria. Biochemistry 2006;45:12400-10]. We reported that chloroquine (CQ) treatment did not appear to affect progress through the cell cycle, and suggested that toxicity may be manifested post-schizogony. We now use SDCM, synchronized cell culture and continuous vs. bolus drug dosing to investigate stage specific CQ effects in detail. We develop a novel, extremely rapid method for counting schizont nuclei in 3D. We then quantify schizont nuclei and hemozoin (Hz) production for live parasite cultures pulsed with CQ at different stages in the cell cycle and find that bolus treatment of rings affects the multiplicity of nuclear division. We quantify parasitemia and merozoite development in subsequent cycles following bolus CQ exposure and find that a portion of CQ toxicity is manifested post-schizogony as "delayed death". Using these methods and others we compare CQ sensitive (CQS) vs. resistant (CQR) strains as well as transfectants that are CQR via introduction of mutant PfCRT. Surprisingly, we find that PfCRT confers resistance to CQ administered at the very early ring stage of development, wherein a digestive vacuole is not yet formed, as well as at the schizont stage, wherein Hz production is thought to plateau. Taken together, these data force a rethinking of CQ pharmacology and the mechanism of CQR.
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Affiliation(s)
- Bojana Gligorijevic
- Department of Chemistry and Center for Infectious Diseases, Georgetown University, 37th and O Streets, Washington, DC 20057, USA
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Uyen DT, Huy NT, Trang DTX, Nhien NTT, Oida T, Hirayama K, Harada S, Kamei K. Effects of Amino Acids on Malarial Heme Crystallization. Biol Pharm Bull 2008; 31:1483-8. [DOI: 10.1248/bpb.31.1483] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Dinh Thanh Uyen
- Department of Applied Biology, Kyoto Institute of Technology
| | - Nguyen Tien Huy
- Department of Applied Biology, Kyoto Institute of Technology
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Nagasaki University
| | | | | | - Tatsuo Oida
- Department of Materials and Science, Kyoto Institute of Technology
| | - Kenji Hirayama
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Nagasaki University
| | | | - Kaeko Kamei
- Department of Applied Biology, Kyoto Institute of Technology
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Hemozoin: oil versus water. Parasitol Int 2007; 57:89-96. [PMID: 18373972 DOI: 10.1016/j.parint.2007.09.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Revised: 09/26/2007] [Accepted: 09/28/2007] [Indexed: 11/23/2022]
Abstract
Because the quinolines inhibit heme crystallization within the malaria parasite much work has focused on mechanism of formation and inhibition of hemozoin. Here we review the recent evidence for heme crystallization within lipids in diverse parasites and the new implications of a lipid site of crystallization for drug targeting. Within leukocytes hemozoin can generate toxic radical lipid metabolites, which may alter immune function or reduce deformability of uninfected erythrocytes.
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Schlitzer M. Malaria Chemotherapeutics Part I: History of Antimalarial Drug Development, Currently Used Therapeutics, and Drugs in Clinical Development. ChemMedChem 2007; 2:944-86. [PMID: 17530725 DOI: 10.1002/cmdc.200600240] [Citation(s) in RCA: 179] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Since ancient times, humankind has had to struggle against the persistent onslaught of pathogenic microorganisms. Nowadays, malaria is still the most important infectious disease worldwide. Considerable success in gaining control over malaria was achieved in the 1950s and 60s through landscaping measures, vector control with the insecticide DDT, and the widespread administration of chloroquine, the most important antimalarial agent ever. In the late 1960s, the final victory over malaria was believed to be within reach. However, the parasites could not be eradicated because they developed resistance against the most widely used and affordable drugs of that time. Today, cases of malaria infections are on the rise and have reached record numbers. This review gives a short description of the malaria disease, briefly addresses the history of antimalarial drug development, and focuses on drugs currently available for malaria therapy. The present knowledge regarding their mode of action and the mechanisms of resistance are explained, as are the attempts made by numerous research groups to overcome the resistance problem within classes of existing drugs and in some novel classes. Finally, this review covers all classes of antimalarials for which at least one drug candidate is in clinical development. Antimalarial agents that are solely in early development stages will be addressed in a separate review.
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Affiliation(s)
- Martin Schlitzer
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032 Marburg, Germany.
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Lu PJ, Sims PA, Oki H, Macarthur JB, Weitz DA. Target-locking acquisition with real-time confocal (TARC) microscopy. OPTICS EXPRESS 2007; 15:8702-12. [PMID: 19547205 DOI: 10.1364/oe.15.008702] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We present a real-time target-locking confocal microscope that follows an object moving along an arbitrary path, even as it simultaneously changes its shape, size and orientation. This Target-locking Acquisition with Realtime Confocal (TARC) microscopy system integrates fast image processing and rapid image acquisition using a Nipkow spinning-disk confocal microscope. The system acquires a 3D stack of images, performs a full structural analysis to locate a feature of interest, moves the sample in response, and then collects the next 3D image stack. In this way, data collection is dynamically adjusted to keep a moving object centered in the field of view. We demonstrate the system's capabilities by target-locking freely-diffusing clusters of attractive colloidal particles, and activelytransported quantum dots (QDs) endocytosed into live cells free to move in three dimensions, for several hours. During this time, both the colloidal clusters and live cells move distances several times the length of the imaging volume.
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