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Vallintine T, van Ooij C. Distribution of malaria parasite-derived phosphatidylcholine in the infected erythrocyte. mSphere 2023; 8:e0013123. [PMID: 37606582 PMCID: PMC10597409 DOI: 10.1128/msphere.00131-23] [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: 03/15/2023] [Accepted: 07/05/2023] [Indexed: 08/23/2023] Open
Abstract
Malaria parasites modify their host erythrocyte in multiple ways, leading to changes in the deformability, adhesiveness, and permeability of the host erythrocyte. Most of these changes are mediated by proteins exported from the parasite to the host erythrocyte, where these proteins interact with the host cell cytoskeleton or form complexes in the plasma membrane of the infected erythrocyte. In addition, malaria parasites induce the formation of membranous compartments-the parasitophorous vacuole, the tubovesicular network (TVN), the Maurer's clefts and small vesicles-within the infected erythrocyte, a cell that is normally devoid of internal membranes. After infection, changes also occur in the composition and asymmetry of the erythrocyte plasma membrane. Although many aspects of the mechanism of export of parasite proteins have become clear, the mechanism by which these membranous compartments are formed and expanded is almost entirely unknown. To determine whether parasite-derived phospholipids play a part in these processes, we applied a metabolic labeling technique that allows phosphatidylcholine to be labeled with a fluorophore. As the host erythrocyte cannot synthesize phospholipids, within infected erythrocytes, only parasite-derived phosphatidylcholine will be labeled with this technique. The results revealed that phosphatidylcholine produced by the parasite is distributed throughout the infected erythrocyte, including the TVN and the erythrocyte plasma membrane, but not Maurer's clefts. Interestingly, labeled phospholipids were also detected in the erythrocyte plasma membrane very soon after invasion of the parasites, indicating that the parasite may add phospholipids to the host erythrocyte during invasion. IMPORTANCE Here, we describe a previously unappreciated way in which the malaria parasite interacts with the host erythrocyte, namely, by the transfer of parasite phospholipids to the erythrocyte plasma membrane. This likely has important consequences for the survival of the parasite in the host cell and the host organism. We show that parasite-derived phospholipids are transferred from the parasite to the host erythrocyte plasma membrane and that other internal membranes that are produced after the parasite has invaded the cell are produced, at least in part, using parasite-derived phospholipids. The one exception to this is the Maurer's cleft, a membranous organelle that is involved in the transport of parasite proteins to the surface of the erythrocyte. This reveals that the Maurer's cleft is produced in a different manner than the other parasite-induced membranes. Overall, these findings provide a platform for the study of a new aspect of the host-parasite interaction.
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Affiliation(s)
- Tansy Vallintine
- Department of Infection Biology, Faculty of Infectious Disease, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Christiaan van Ooij
- Department of Infection Biology, Faculty of Infectious Disease, London School of Hygiene & Tropical Medicine, London, United Kingdom
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2
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Maier AG, van Ooij C. The role of cholesterol in invasion and growth of malaria parasites. Front Cell Infect Microbiol 2022; 12:984049. [PMID: 36189362 PMCID: PMC9522969 DOI: 10.3389/fcimb.2022.984049] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 08/15/2022] [Indexed: 11/24/2022] Open
Abstract
Malaria parasites are unicellular eukaryotic pathogens that develop through a complex lifecycle involving two hosts, an anopheline mosquito and a vertebrate host. Throughout this lifecycle, the parasite encounters widely differing conditions and survives in distinct ways, from an intracellular lifestyle in the vertebrate host to exclusively extracellular stages in the mosquito. Although the parasite relies on cholesterol for its growth, the parasite has an ambiguous relationship with cholesterol: cholesterol is required for invasion of host cells by the parasite, including hepatocytes and erythrocytes, and for the development of the parasites in those cells. However, the parasite is unable to produce cholesterol itself and appears to remove cholesterol actively from its own plasma membrane, thereby setting up a cholesterol gradient inside the infected host erythrocyte. Overall a picture emerges in which the parasite relies on host cholesterol and carefully controls its transport. Here, we describe the role of cholesterol at the different lifecycle stages of the parasites.
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Affiliation(s)
- Alexander G. Maier
- Research School of Biology, The Australian National University, Canberra ACT, Australia
- *Correspondence: Alexander G. Maier, ; Christiaan van Ooij,
| | - Christiaan van Ooij
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, United Kingdom
- *Correspondence: Alexander G. Maier, ; Christiaan van Ooij,
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3
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Iso-O N, Komatsuya K, Tokumasu F, Isoo N, Ishigaki T, Yasui H, Yotsuyanagi H, Hara M, Kita K. Malaria Parasites Hijack Host Receptors From Exosomes to Capture Lipoproteins. Front Cell Dev Biol 2021; 9:749153. [PMID: 34858976 PMCID: PMC8631964 DOI: 10.3389/fcell.2021.749153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/27/2021] [Indexed: 12/17/2022] Open
Abstract
Malaria parasites cannot multiply in host erythrocytes without cholesterol because they lack complete sterol biosynthesis systems. This suggests parasitized red blood cells (pRBCs) need to capture host sterols, but its mechanism remains unknown. Here we identified a novel high-density lipoprotein (HDL)-delivery pathway operating in blood-stage Plasmodium. In parasitized mouse plasma, exosomes positive for scavenger receptor CD36 and platelet-specific CD41 increased. These CDs were detected in pRBCs and internal parasites. A low molecular antagonist for scavenger receptors, BLT-1, blocked HDL uptake to pRBCs and suppressed Plasmodium growth in vitro. Furthermore, platelet-derived exosomes were internalized in pRBCs. Thus, we presume CD36 is delivered to malaria parasites from platelets by exosomes, which enables parasites to steal HDL for cholesterol supply. Cholesterol needs to cross three membranes (RBC, parasitophorous vacuole and parasite’s plasma membranes) to reach parasite, but our findings can explain the first step of sterol uptake by intracellular parasites.
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Affiliation(s)
- Naoyuki Iso-O
- The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.,Department of 4th Internal Medicine, Teikyo University Mizonokuchi Hospital, Kawasaki, Japan
| | - Keisuke Komatsuya
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.,Laboratory of Biomembrane, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Fuyuki Tokumasu
- Department of Lipidomics, The University of Tokyo, Tokyo, Japan.,Department of Cellular Architecture Studies, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Noriko Isoo
- Department of Physiology, Teikyo University School of Medicine, Tokyo, Japan
| | - Tomohiro Ishigaki
- The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Yasui
- The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | | | - Masumi Hara
- Department of 4th Internal Medicine, Teikyo University Mizonokuchi Hospital, Kawasaki, Japan
| | - Kiyoshi Kita
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.,School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan.,Department of Host-Defense Biochemistry, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
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4
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Alsultan M, Morriss J, Contaifer D, Kumar NG, Wijesinghe DS. Host Lipid Response in Tropical Diseases. CURRENT TREATMENT OPTIONS IN INFECTIOUS DISEASES 2020. [DOI: 10.1007/s40506-020-00222-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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5
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Lu C, Zheng X, Zhang W, Zhao H, MacRaild CA, Norton RS, Zhuang Y, Wang J, Zhang X. Interaction of merozoite surface protein 2 with lipid membranes. FEBS Lett 2019; 593:288-295. [PMID: 30588612 DOI: 10.1002/1873-3468.13320] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 11/26/2018] [Accepted: 12/16/2018] [Indexed: 11/07/2022]
Abstract
Merozoite surface protein 2 (MSP2) is a potential vaccine candidate against malaria, although its functional role is yet to be elucidated. Previous studies showed that MSP2 can interact with membranes, which may facilitate merozoite invasion into the host cell. The N-terminal 25 residues of MSP2 (MSP21-25 ), which may be aggregated on the merozoite surface, play a key role in the interaction with membranes. Here, we investigated the effects of MSP21-25 -membrane interactions on the conformation and aggregation of MSP21-25 and on membrane integrity, using nanodiscs and small unilamellar vesicles as mimetics of cell membranes. MSP21-25 -membrane interactions induced the peptide to form β-structure and to aggregate, depending on the lipid composition of the membrane. Nonfibrillar aggregates in turn disrupted the membrane.
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Affiliation(s)
- Chenghui Lu
- School of Life Sciences, Anhui University, Hefei, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, China
| | - Xue Zheng
- School of Life Sciences, Anhui University, Hefei, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, China
| | - Wei Zhang
- School of Life Sciences, Anhui University, Hefei, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, China
| | - Hongxin Zhao
- High Magnetic Field Laboratory, Key Laboratory of Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China
| | - Christopher A MacRaild
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Yonglong Zhuang
- Modern Experimental Technology Center, Anhui University, Hefei, China
| | - Junfeng Wang
- High Magnetic Field Laboratory, Key Laboratory of Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China
- Institute of Physical Science and Information Technology, Anhui University, Hefei, China
| | - Xuecheng Zhang
- School of Life Sciences, Anhui University, Hefei, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, China
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6
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Rivera-Correa J, Guthmiller JJ, Vijay R, Fernandez-Arias C, Pardo-Ruge MA, Gonzalez S, Butler NS, Rodriguez A. Plasmodium DNA-mediated TLR9 activation of T-bet + B cells contributes to autoimmune anaemia during malaria. Nat Commun 2017; 8:1282. [PMID: 29101363 PMCID: PMC5670202 DOI: 10.1038/s41467-017-01476-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 09/20/2017] [Indexed: 01/05/2023] Open
Abstract
Infectious pathogens contribute to the development of autoimmune disorders, but the mechanisms connecting these processes are incompletely understood. Here we show that Plasmodium DNA induces autoreactive responses against erythrocytes by activating a population of B cells expressing CD11c and the transcription factor T-bet, which become major producers of autoantibodies that promote malarial anaemia. Additionally, we identify parasite DNA-sensing through Toll-like receptor 9 (TLR9) along with inflammatory cytokine receptor IFN-γ receptor (IFN-γR) as essential signals that synergize to promote the development and appearance of these autoreactive T-bet+ B cells. The lack of any of these signals ameliorates malarial anaemia during infection in a mouse model. We also identify both expansion of T-bet+ B cells and production of anti-erythrocyte antibodies in ex vivo cultures of naive human peripheral blood mononuclear cells (PBMC) exposed to P. falciprum infected erythrocyte lysates. We propose that synergistic TLR9/IFN-γR activation of T-bet+ B cells is a mechanism underlying infection-induced autoimmune-like responses.
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MESH Headings
- Anemia, Hemolytic, Autoimmune/etiology
- Anemia, Hemolytic, Autoimmune/immunology
- Anemia, Hemolytic, Autoimmune/parasitology
- Animals
- Autoantibodies/biosynthesis
- B-Lymphocyte Subsets/immunology
- B-Lymphocyte Subsets/parasitology
- DNA, Protozoan/immunology
- Erythrocytes/immunology
- Erythrocytes/parasitology
- Female
- Humans
- Lymphocyte Activation
- Malaria, Falciparum/complications
- Malaria, Falciparum/immunology
- Malaria, Falciparum/parasitology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Plasmodium falciparum/immunology
- Plasmodium falciparum/pathogenicity
- Receptors, Interferon/deficiency
- Receptors, Interferon/genetics
- Receptors, Interferon/metabolism
- T-Box Domain Proteins/deficiency
- T-Box Domain Proteins/genetics
- T-Box Domain Proteins/metabolism
- Toll-Like Receptor 9/deficiency
- Toll-Like Receptor 9/genetics
- Toll-Like Receptor 9/metabolism
- Interferon gamma Receptor
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Affiliation(s)
- J Rivera-Correa
- Department of Microbiology, New York University School of Medicine, New York, NY, 10010, USA
| | - J J Guthmiller
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA
| | - R Vijay
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA, 52242, USA
| | - C Fernandez-Arias
- Department of Microbiology, New York University School of Medicine, New York, NY, 10010, USA
| | - M A Pardo-Ruge
- Department of Microbiology, New York University School of Medicine, New York, NY, 10010, USA
| | - S Gonzalez
- Department of Microbiology, New York University School of Medicine, New York, NY, 10010, USA
| | - N S Butler
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA, 52242, USA
| | - A Rodriguez
- Department of Microbiology, New York University School of Medicine, New York, NY, 10010, USA.
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7
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Chen F, Flaherty BR, Cohen CE, Peterson DS, Zhao Y. Direct detection of malaria infected red blood cells by surface enhanced Raman spectroscopy. NANOMEDICINE : NANOTECHNOLOGY, BIOLOGY, AND MEDICINE 2016; 12:1445-51. [PMID: 27015769 PMCID: PMC4955673 DOI: 10.1016/j.nano.2016.03.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 02/04/2016] [Accepted: 03/02/2016] [Indexed: 02/05/2023]
Abstract
Surface enhanced Raman spectra (SERS) of normal red blood cells (RBCs) and Plasmodium falciparum infected RBCs (iRBCs) at different post invasion time were obtained based on silver nanorod array substrates. Distinct spectral differences were observed due to the cell membrane modification of RBCs during malaria infection. The SERS spectra of ring stage iRBCs had a characteristic Raman peak at Δv=1599cm(-1) as compared to those of normal RBCs, while the trophozoite and schizoid stages had identical SERS spectra with a characteristic peak at Δv=723cm(-1), which is significantly different from ring stage iRBCs, consistent with ongoing modification of the iRBC membrane. Since ring stage iRBCs of P. falciparum are found circulating in blood, such a difference provides a new strategy for rapid malaria detection. The limit of detection as well as the ability to detect a mixed iRBC and RBC solution was also investigated.
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Affiliation(s)
- Funing Chen
- Department of Physics and Astronomy, the University of Georgia, Athens, GA, USA; Nanoscale Science & Engineering Center, the University of Georgia, Athens, GA, USA.
| | - Briana R Flaherty
- Department of Infectious Diseases, the University of Georgia, Athens, GA, USA; Center for Tropical and Emerging Global Diseases, the University of Georgia, Athens, GA, USA
| | - Charli E Cohen
- Department of Infectious Diseases, the University of Georgia, Athens, GA, USA
| | - David S Peterson
- Department of Infectious Diseases, the University of Georgia, Athens, GA, USA; Center for Tropical and Emerging Global Diseases, the University of Georgia, Athens, GA, USA
| | - Yiping Zhao
- Department of Physics and Astronomy, the University of Georgia, Athens, GA, USA; Nanoscale Science & Engineering Center, the University of Georgia, Athens, GA, USA
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8
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Tran PN, Brown SHJ, Rug M, Ridgway MC, Mitchell TW, Maier AG. Changes in lipid composition during sexual development of the malaria parasite Plasmodium falciparum. Malar J 2016; 15:73. [PMID: 26852399 PMCID: PMC4744411 DOI: 10.1186/s12936-016-1130-z] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/23/2016] [Indexed: 01/13/2023] Open
Abstract
Background The development of differentiated sexual stages (gametocytes) within human red blood cells is essential for the propagation of the malaria parasite, since only mature gametocytes will survive in the mosquito’s midgut. Hence gametocytogenesis is a pre-requisite for transmission of the disease. Physiological changes involved in sexual differentiation are still enigmatic. In particular the lipid metabolism—despite being central to cellular regulation and development—is not well explored. Methods Here the lipid profiles of red blood cells infected with the five different sexual stages of Plasmodium falciparum were analysed by mass spectrometry and compared to those from uninfected and asexual trophozoite infected erythrocytes. Results Fundamental differences between erythrocytes infected with the different parasite stages were revealed. In mature gametocytes many lipids that decrease in the trophozoite and early gametocyte infected red blood cells are regained. In particular, regulators of membrane fluidity, cholesterol and sphingomyelin, increased significantly during gametocyte maturation. Neutral lipids (serving mainly as caloriometric reserves) increased from 3 % of total lipids in uninfected to 27 % in stage V gametocyte infected red blood cells. The major membrane lipid class (phospholipids) decreased during gametocyte development. Conclusions The lipid profiles of infected erythrocytes are characteristic for the particular parasite life cycle and maturity stages of gametocytes. The obtained lipid profiles are crucial in revealing the lipid metabolism of malaria parasites and identifying targets to interfere with this deadly disease. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1130-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Phuong N Tran
- Research School of Biology, The Australian National University, Canberra, ACT, Australia. .,La Trobe Institute of Molecular Science, La Trobe University, Melbourne, VIC, Australia.
| | - Simon H J Brown
- School of Medicine and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia.
| | - Melanie Rug
- Research School of Biology, The Australian National University, Canberra, ACT, Australia. .,Centre for Advanced Microscopy, The Australian National University, Canberra, ACT, Australia.
| | - Melanie C Ridgway
- Research School of Biology, The Australian National University, Canberra, ACT, Australia.
| | - Todd W Mitchell
- School of Medicine and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia.
| | - Alexander G Maier
- Research School of Biology, The Australian National University, Canberra, ACT, Australia.
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9
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Statins as potential antimalarial drugs: low relative potency and lack of synergy with conventional antimalarial drugs. Antimicrob Agents Chemother 2009; 53:2212-4. [PMID: 19258270 DOI: 10.1128/aac.01469-08] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The in vitro sensitivity of Plasmodium falciparum to atorvastatin and rosuvastatin was assessed using chloroquine-sensitive and chloroquine-resistant strains. Although atorvastatin was more potent, it had weak activity (mean 50% inhibitory concentration of > or = 17 microM) and an indifferent interaction with chloroquine and dihydroartemisinin. Bioassay of plasma from an atorvastatin-treated subject showed similar results.
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10
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Atella GC, Bittencourt-Cunha PR, Nunes RD, Shahabuddin M, Silva-Neto MAC. The major insect lipoprotein is a lipid source to mosquito stages of malaria parasite. Acta Trop 2009; 109:159-62. [PMID: 19013123 DOI: 10.1016/j.actatropica.2008.10.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Revised: 09/30/2008] [Accepted: 10/01/2008] [Indexed: 11/30/2022]
Abstract
Once mosquito midgut barrier was crossed malaria parasite faces a extensive metabolic developmental program in order to ensure its transmission. In the hemolymph of the mosquito the dynamics of lipid metabolism is conducted by a major lipoprotein, lipophorin (Lp). It was recently shown that Lp is engaged in the mosquito immune response to parasite infection. However, it is not clear if Lp is uptaken by the parasite. Here, we show that oocysts are able to uptake mosquito Lp. The uptake of FITC-labeled Lp was demonstrated in midgut-associated oocysts. Alternatively, to confirm Lp incorporation by oocysts we have conducted another set of experiments with iodinated Lp ((125)I-Lp). Oocysts were able to incorporate (125)I-Lp and the process is both time and temperature dependent. This set of results indicated that no matter oocysts are attached to mosquito midgut wall they bear a lipid sequestering machinery from its surroundings. Phospholipid transfer to sporozoites was also demonstrated. In conclusion, these results demonstrate for the first time that malaria parasite undergoes lipid uptake while in the invertebrate host.
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Affiliation(s)
- Georgia C Atella
- Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
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11
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Coppens I, Vielemeyer O. Insights into unique physiological features of neutral lipids in Apicomplexa: from storage to potential mediation in parasite metabolic activities. Int J Parasitol 2005; 35:597-615. [PMID: 15862574 DOI: 10.1016/j.ijpara.2005.01.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2004] [Revised: 01/05/2005] [Accepted: 01/13/2005] [Indexed: 01/18/2023]
Abstract
The fast intracellular multiplication of apicomplexan parasites including Toxoplasma and Plasmodium, requires large amounts of lipids necessary for the membrane biogenesis of new progenies. Hence, the study of lipids is fundamental in order to understand the biology and pathogenesis of these deadly organisms. Much has been reported on the importance of polar lipids, e.g. phospholipids in Plasmodium. Comparatively, little attention has been paid to the metabolism of neutral lipids, including sterols, steryl esters and acylglycerols. In eukaryotic cells, free sterols are membrane components whereas steryl esters and acylglycerols are stored in cytosolic lipid inclusions. The first part of this review describes the recent advances in neutral lipid synthesis and storage in Toxoplasma and Plasmodium. New potential pharmacological targets in the pathways producing neutral lipids are outlined. In addition to lipid bodies, Apicomplexa contain unique secretory organelles involved in parasite invasion named rhoptries. These compartments appear to sequester most of the cholesterol found in the exocytic pathway. The second part of the review focuses on rhoptry cholesterol and its potential roles in the biogenesis, structural organisation and function of these unique organelles among eukaryotes.
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Affiliation(s)
- Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205-2223, USA.
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12
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Simões AP, Roelofsen B, Op den Kamp JA. Lipid compartmentalization in erythrocytes parasitized by Plasmodium spp. ACTA ACUST UNITED AC 2005; 8:18-21. [PMID: 15463520 DOI: 10.1016/0169-4758(92)90305-l] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Although reasonably well protected from the host immune system by the erythrocyte membrane, the intraerythrocytic malaria parasite has to make that membrane compatible with its own requirements for development and multiplication. The development of Plasmodium spp brings about major changes in the lipid composition of the host cell membrane, as well as in its physical properties. The parasite itself has a lipid composition that differs from that of the host cell and an intense lipid trafficking seems to occur between intracellular parasite and host cell membrane. Here, Ana Paula Simões, Ben Roelofsen and Jos Op den Kamp discuss how, despite serious methodological limitations and the existence of some conflicting results, an overall picture of lipid compartmentalization within the parasitized erythrocyte is perceived.
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Affiliation(s)
- A P Simões
- Centre for Biomembranes and Lipid Enzymology, University of Utrecht, PO Box 80054, 3508 TB, Utrecht, The Netherlands
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13
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Vielemeyer O, McIntosh MT, Joiner KA, Coppens I. Neutral lipid synthesis and storage in the intraerythrocytic stages of Plasmodium falciparum. Mol Biochem Parasitol 2004; 135:197-209. [PMID: 15110461 DOI: 10.1016/j.molbiopara.2003.08.017] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2003] [Revised: 06/23/2003] [Accepted: 08/18/2003] [Indexed: 11/20/2022]
Abstract
In eukaryotic cells the neutral lipids, steryl esters and triacylglycerol, are synthesized by membrane-bound O-acyltransferases and stored in cytosolic lipid bodies. We show here that the intraerythrocytic stages of Plasmodium falciparum produce triacylglycerol using oleate and diacylglycerol as substrates. Parasite membrane preparations reveal a synthesis rate of 4.5 +/- 0.8 pmol x min(-1)mg(-1) of protein with maximal production occurring in the mid- and late-trophozoite stages in both, membrane preparations and live parasites. In contrast to other eukaryotic cells, no discernable amounts of steryl esters are produced, and the parasite is insensitive to cholesterol esterification inhibitors. Synthesized neutral lipids are stored as lipid bodies in the parasite cytosol in a stage specific manner. Their biogenesis is not modified upon incubation with excess fatty acids or lipoproteins or after lipoprotein depletion of the culture medium. We investigated on the enzymes involved in neutral lipid synthesis and found that only one gene with significant homology to known members of the membrane-bound O-acyltransferase family is present in the P. falciparum genome. It encodes a microsomal transmembrane protein with a predicted size of 78.1 kDa, which we named PfDGAT because of its close identity with various known acyl-CoA:diacylglycerol acyltransferases. PfDGAT is expressed in a stage specific manner as documented by Western blotting and immunoprecipitation assays using antibodies against Toxoplasma DGAT, suggesting that PfDGAT is the most likely candidate for plasmodial triacylglycerol synthesis.
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Affiliation(s)
- Ole Vielemeyer
- Department of Internal Medicine, Yale University School of Medicine, 333 Cedar Street, PO Box 20822, New Haven, CT 06520-8022, USA
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14
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Tomas AM, Margos G, Dimopoulos G, van Lin LH, de Koning-Ward TF, Sinha R, Lupetti P, Beetsma AL, Rodriguez MC, Karras M, Hager A, Mendoza J, Butcher GA, Kafatos F, Janse CJ, Waters AP, Sinden RE. P25 and P28 proteins of the malaria ookinete surface have multiple and partially redundant functions. EMBO J 2001; 20:3975-83. [PMID: 11483501 PMCID: PMC149139 DOI: 10.1093/emboj/20.15.3975] [Citation(s) in RCA: 162] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The ookinete surface proteins (P25 and P28) are proven antimalarial transmission-blocking vaccine targets, yet their biological functions are unknown. By using single (Sko) and double gene knock-out (Dko) Plasmodium berghei parasites, we show that P25 and P28 share multiple functions during ookinete/oocyst development. In the midgut of mosquitoes, the formation of ookinetes lacking both proteins (Dko parasites) is significantly inhibited due to decreased protection against lethal factors, including protease attack. In addition, Dko ookinetes have a much reduced capacity to traverse the midgut epithelium and to transform into the oocyst stage. P25 and P28 are partially redundant in these functions, since the efficiency of ookinete/oocyst development is only mildly compromised in parasites lacking either P25 or P28 (Sko parasites) compared with that of Dko parasites. The fact that Sko parasites are efficiently transmitted by the mosquito is a compelling reason for including both target antigens in transmission-blocking vaccines.
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Affiliation(s)
| | - Gabriele Margos
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | - George Dimopoulos
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | | | | | - Ria Sinha
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | - Pietro Lupetti
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | - Annette L. Beetsma
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | - Maria C. Rodriguez
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | - Marianna Karras
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | - Ariadne Hager
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | - Jacqui Mendoza
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | - Geoffrey A. Butcher
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | - Fotis Kafatos
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
| | | | | | - Robert E. Sinden
- Leiden University Medical Centre, Laboratory of Parasitology, PO Box 9605, 2300 RC Leiden, The Netherlands,
Imperial College of Science, Technology and Medicine, Biology Department, Sir Alexander Fleming Building, Imperial College Road, London SW7 2AZ, UK, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany and Unit of Electron Microscopy and Cryotechniques, Dipartimento Biologia Evolutiva, Università di Siena, Via P.A. Mattioli 4, 53100 Siena, Italy Corresponding author e-mail:
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15
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El Alaoui H, Bata J, Bauchart D, Doré JC, Vivarès CP. Lipids of three microsporidian species and multivariate analysis of the host-parasite relationship. J Parasitol 2001; 87:554-9. [PMID: 11426718 DOI: 10.1645/0022-3395(2001)087[0554:lotmsa]2.0.co;2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Sporal lipids of 3 microsporidia, Encephalitozoon cuniculi from mammals and Glugea atherinae and Spraguea lophii from fishes, were investigated. High phospholipid levels were found (54.8-64.5% of total lipids), which is in agreement with the presence of highly developed internal membranes in microsporidian spores. Sphingomyelin was not detected in G. atherinae. Triglycerides (less than 10% of total lipids), cholesterol, and free fatty acids were identified in all species. Analysis of fatty acids from the phospholipid fraction revealed the predominance of docosahexaenoic acid (30-40% of total phospholipid fatty acids) in G. atherinae and S. lophii and oleic acid (25.8% of total phospholipid fatty acids) in E. cuniculi. The 3 microsporidia possessed a significant amount of branched-chain fatty acids (iso and anteiso forms) not found in the hosts, supporting the existence of some parasite-specific metabolic steps for these fatty acids. On the basis of phospholipid fatty acid profiles, host-parasite relationships were investigated through correspondence factorial analysis. It shows 3 distinct clusters with the first corresponding to fishes, the second to fish parasites, and the third to E. cuniculi and its host cell. These data suggest that the mammal microsporidia developing within parasitophorous vacuoles are more dependent on host cells than the fish microsporidia that induce cystlike structures.
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Affiliation(s)
- H El Alaoui
- Laboratoire de Parasitologie Moléculaire et Cellulaire, LBP, UMR CNRS 6023, Université Blaise Pascal, Aubière, France
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16
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Soudant P, Chu FL. Lipid class and fatty acid composition of the protozoan parasite of oysters, Perkinsus marinus cultivated in two different media. J Eukaryot Microbiol 2001; 48:309-19. [PMID: 11411839 DOI: 10.1111/j.1550-7408.2001.tb00319.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The meront stage of the oyster protozoan parasite, Perkinsus marinus, cultivated in two media with different fatty acid profiles was analyzed for its fatty acid and lipid class composition. The composition of fatty acids in the prezoosporangium stage of the parasite as well as that of the host oyster were investigated. Although the lipid class composition of meronts was dominated by phospholipids and triacylglycerol, there was no triaclgycerol detected in either culture medium. Despite the difference in fatty acid composition of the two media, the fatty acid composition of meronts in each medium was dominated by 14:0, 16:0, 18:0, 18:1(n-9), 20: (n-9), 18:2(n-6) and 20:4(n-6), a profile that differed from its host. The quantities of total lipids and fatty acids in meronts increased as the number of meronts increased and far exceeded the initial amounts in the media and in the initial cell inoculum. The meronts harvested 25 d post-inoculation, had about 3 to 6 times higher total lipids and 4 to 13 times higher fatty acids than the amounts contained in the media. The fatty acid profiles of both prezoosporangia and oysters resembled each other and consisted primarily of 16:0, 20:4(n-6), 20:5(n-3), 22:2delta7,15, and 22:6(n-3). These results indicate that during meront proliferation, the parasite synthesizes certain fatty acids and lipid classes. For development from meront to prezoosporangium, the parasite may rely on its host for lipid resources.
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Affiliation(s)
- P Soudant
- Virginia Institute of Marine Science, College of William and Mary, Virginia 23062, USA
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17
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Abstract
The malaria parasite is a unicellular eukaryotic organism which, during the course of its complex life cycle, invades the red blood cells of its vertebrate host. As it grows and multiplies within its host blood cell, the parasite modifies the membrane permeability and cytosolic composition of the host cell. The intracellular parasite is enclosed within a so-called parasitophorous vacuolar membrane, tubular extensions of which radiate out into the host cell compartment. Like all eukaryote cells, the parasite has at its surface a plasma membrane, as well as having a variety of internal membrane-bound organelles that perform a range of functions. This review focuses on the transport properties of the different membranes of the malaria-infected erythrocyte, as well as on the role played by the various membrane transport systems in the uptake of solutes from the extracellular medium, the disposal of metabolic wastes, and the origin and maintenance of electrochemical ion gradients. Such systems are of considerable interest from the point of view of antimalarial chemotherapy, both as drug targets in their own right and as routes for targeting cytotoxic agents into the intracellular parasite.
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Affiliation(s)
- K Kirk
- Division of Biochemistry and Molecular Biology, Faculty of Science, Australian National University, Canberra, Australian Capital Territory, Australia.
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18
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Mitschler RR, Welti R, Upton SJ. A comparative study of lipid compositions of Cryptosporidium parvum (Apicomplexa) and Madin-Darby bovine kidney cells. J Eukaryot Microbiol 1994; 41:8-12. [PMID: 8124271 DOI: 10.1111/j.1550-7408.1994.tb05927.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Membrane lipid compositions of Cryptosporidium parvum and Madin-Darby bovine kidney cells, an epithelial-like cell line commonly used to study coccidia in vitro, were analyzed using both thin-layer chromatography and gas-liquid chromatography. Phosphatidylcholine was the predominant lipid in both C. parvum and Madin-Darby bovine kidney cells, comprising 65% and 41% of the total phospholipids, respectively. Phospholipids of C. parvum contained twice the level of 16:0 and twenty-fold more 18:2 than the Madin-Darby bovine kidney cell line. We suggest that the parasite may be capable of sequestering specific complex membrane lipids at concentrations greater than those in the host cells. This study constitutes the first report of the lipid composition of C. parvum.
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Affiliation(s)
- R R Mitschler
- Division of Biology, Kansas State University, Manhattan 66506
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19
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Fiebig S, Simões AP, Wunderlich F, op den Kamp JA. Testosterone-induced changes in phosphatidylcholine molecular species composition of Plasmodium chabaudi-infected erythrocytes. Parasitology 1993; 107 ( Pt 5):465-9. [PMID: 8295785 DOI: 10.1017/s0031182000068037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This study is concerned with the influence of testosterone on the phospholipid class and the phosphatidylcholine molecular species composition of various fractions obtained from the blood of Plasmodium chabaudi-infected mice. Blood plasma, infected erythrocytes, isolated parasites and erythrocyte membranes isolated from both non-infected and infected erythrocytes in the form of ghosts were analysed. In general, the phospholipid classes remained unaffected, while the phosphatidylcholine (PC) molecular species composition showed differences after testosterone treatment. In infected erythrocytes, there was a decrease in 16:0/20:4-PC and 18:0/20:4-PC and an increase in 16:0/18:2(16:0/20:3)-PC. The decrease of 16:0/20:4-PC was exclusively confined to parasites. The rise in 16:0/18:2(16:0/20:3)-PC and the diminution of 18:0/20:4-PC occurred in the erythrocyte membrane of both infected ghosts and non-infected ghosts as well as in the blood plasma. It is suggested that these changes occur primarily in the plasma thereby influencing the erythrocyte membranes. The decrease in 16:0/20:4-PC supports the view of the independence of the parasite from the biosynthetic lipid pathways of its host cell.
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Affiliation(s)
- S Fiebig
- Division of Parasitology, Heinrich-Heine-University, Düsseldorf, Germany
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20
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Simões AP, Fiebig S, Wunderlich F, Vial H, Roelofsen B, Op den Kamp JA. Plasmodium chabaudi-parasitized erythrocytes: phosphatidylcholine species of parasites and host cell membranes. Mol Biochem Parasitol 1993; 57:345-8. [PMID: 8433723 DOI: 10.1016/0166-6851(93)90211-f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- A P Simões
- C.B.L.E., University of Utrecht, The Netherlands
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21
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Zidovetzki R, Sherman IW, Cardenas M, Borchardt DB. Chloroquine stabilization of phospholipid membranes against diacylglycerol-induced perturbation. Biochem Pharmacol 1993; 45:183-9. [PMID: 8424811 DOI: 10.1016/0006-2952(93)90391-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The effects of 1-stearoyl,2-sn-arachidonoylglycerol (SAG) and the antimalarial drug chloroquine on lipid bilayer structure were studied by 2H-NMR spectroscopy. Model lipid systems were established with compositions similar to those of normal human erythrocytes, malaria-infected erythrocytes, or malaria parasite membranes. The 2H-NMR spectra of the membranes formed from the lipids extracted from normal human erythrocytes were similar to those obtained using the corresponding lipid mixtures. The order parameters of the model "infected" and model "parasite" membranes were reduced markedly relative to that of normal erythrocytes. Addition of SAG induced formation of non-bilayer lipid phases in all lipid systems. Only a small decrease in the order parameters of the acyl side chains of the phosphatidylserine, but not of the phosphatidylcholine component of the lipid membranes, was observed upon the addition of chloroquine. A dramatic effect was observed upon the addition of chloroquine to the SAG-containing membranes: this antimalarial almost totally abolished the formation of SAG-induced non-bilayer lipid phases. Since SAG, endogenously formed in erythrocyte membranes, is a potent activator of phospholipase A2, this membrane-stabilizing action of chloroquine may partially account for the phospholipase A2-inhibiting properties of this drug, and, consequently, for both its therapeutic and toxic modes of action.
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Affiliation(s)
- R Zidovetzki
- Department of Biology, University of California, Riverside 92521
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22
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Abstract
Susceptibility to oxidative stress is a well-established feature of the malarial parasite. Pharmacologists have taken advantage of this property to design highly effective pro-oxidant antimalarial drugs. Less well appreciated is the fact that nutritional manipulation of host oxidative stress status by dietary means can have a profound effect on the growth of the parasite. In particular, rapid induction of vitamin E deficiency in mice by feeding highly unsaturated fatty acids (fish oil) strongly suppresses plasmodial growth. Likewise, the status of other antioxidant nutrients (e.g., riboflavin or vitamin C) may also influence the course of malarial infection under certain conditions. A combined nutritional pharmacology approach may offer some promise in controlling malaria.
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Affiliation(s)
- O A Levander
- Vitamin and Mineral Nutrition Laboratory, Beltsville Human Nutrition Research Center, U.S. Department of Agriculture, Maryland 20705-2350
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23
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Naumann KM, Jones GL, Saul A, Smith R. Parasite-induced changes to localized erythrocyte membrane deformability in Plasmodium falciparum cultures. Immunol Cell Biol 1992; 70 ( Pt 4):267-75. [PMID: 1427985 DOI: 10.1038/icb.1992.34] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effect of intra-erythrocyte development of the Plasmodium falciparum parasite on local deformability of human erythrocyte membranes was studied by aspiration of cells into 0.56 micron diameter pores in polycarbonate filters and examination, after fixing, with a scanning electron microscope. As the aspiration pressure increased, the erythrocyte membrane was extruded into the filter pores. The pressure dependence of the protrusion length and the minimum pressure required to produce any deformation provided measures of the membrane shear and the bending moduli, respectively. At the trophozoite and, to a greater extent, schizont stage of development, host cell membrane deformability was significantly decreased. There was no appreciable difference between uninfected and ring-infected erythrocytes.
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Affiliation(s)
- K M Naumann
- Department of Biochemistry, University of Queensland, Australia
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