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Fraser M, Curtis B, Phillips P, Yates PA, Lam KS, Netzel O, van Dooren GG, Ingmundson A, Matuschewski K, McLeod MD, Maier AG. Harnessing cholesterol uptake of malaria parasites for therapeutic applications. EMBO Mol Med 2024; 16:1515-1532. [PMID: 38862600 PMCID: PMC11251039 DOI: 10.1038/s44321-024-00087-1] [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: 10/18/2023] [Revised: 05/14/2024] [Accepted: 05/24/2024] [Indexed: 06/13/2024] Open
Abstract
Parasites, such as the malaria parasite P. falciparum, are critically dependent on host nutrients. Interference with nutrient uptake can lead to parasite death and, therefore, serve as a successful treatment strategy. P. falciparum parasites cannot synthesise cholesterol, and instead source this lipid from the host. Here, we tested whether cholesterol uptake pathways could be 'hijacked' for optimal drug delivery to the intracellular parasite. We found that fluorescent cholesterol analogues were delivered from the extracellular environment to the intracellular parasite. We investigated the uptake and inhibitory effects of conjugate compounds, where proven antimalarial drugs (primaquine and artesunate) were attached to steroids that mimic the structure of cholesterol. These conjugated antimalarial drugs improved the inhibitory effects against multiple parasite lifecycle stages, multiple parasite species, and drug-resistant parasites, whilst also lowering the toxicity to human host cells. Steroids with introduced peroxides also displayed antimalarial activity. These results provide a proof-of-concept that cholesterol mimics can be developed as a drug delivery system against apicomplexan parasites with the potential to improve drug efficacy, increase therapeutic index, and defeat drug resistance.
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Affiliation(s)
- Merryn Fraser
- Research School of Biology, The Australian National University, Canberra, 2601, Australia
- Department of Molecular Parasitology, Institute of Biology, Humboldt University, Berlin, 10115, Germany
- Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, 02115, USA
| | - Blake Curtis
- Research School of Chemistry, The Australian National University, Canberra, 2601, Australia
- Metabolism of Microbial Pathogens, Robert Koch Institute, Berlin, 13353, Germany
| | - Patrick Phillips
- Research School of Biology, The Australian National University, Canberra, 2601, Australia
| | - Patrick A Yates
- Research School of Chemistry, The Australian National University, Canberra, 2601, Australia
| | - Kwong Sum Lam
- Research School of Biology, The Australian National University, Canberra, 2601, Australia
| | - Otto Netzel
- Department of Molecular Parasitology, Institute of Biology, Humboldt University, Berlin, 10115, Germany
| | - Giel G van Dooren
- Research School of Biology, The Australian National University, Canberra, 2601, Australia
| | - Alyssa Ingmundson
- Department of Molecular Parasitology, Institute of Biology, Humboldt University, Berlin, 10115, Germany
| | - Kai Matuschewski
- Department of Molecular Parasitology, Institute of Biology, Humboldt University, Berlin, 10115, Germany
| | - Malcolm D McLeod
- Research School of Chemistry, The Australian National University, Canberra, 2601, Australia.
| | - Alexander G Maier
- Research School of Biology, The Australian National University, Canberra, 2601, Australia.
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2
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Bekić V, Kilian N. Novel secretory organelles of parasite origin - at the center of host-parasite interaction. Bioessays 2023; 45:e2200241. [PMID: 37518819 DOI: 10.1002/bies.202200241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 06/26/2023] [Accepted: 06/28/2023] [Indexed: 08/01/2023]
Abstract
Reorganization of cell organelle-deprived host red blood cells by the apicomplexan malaria parasite Plasmodium falciparum enables their cytoadherence to endothelial cells that line the microvasculature. This increases the time red blood cells infected with mature developmental stages remain within selected organs such as the brain to avoid the spleen passage, which can lead to severe complications and cumulate in patient death. The Maurer's clefts are a novel secretory organelle of parasite origin established by the parasite in the cytoplasm of the host red blood cell in order to facilitate the establishment of cytoadherence by conducting the trafficking of immunovariant adhesins to the host cell surface. Another important function of the organelle is the sorting of other proteins the parasite traffics into its host cell. Although the organelle is of high importance for the pathology of malaria, additional putative functions, structure, and genesis remain shrouded in mystery more than a century after its discovery. In this review, we highlight our current knowledge about the Maurer's clefts and other novel secretory organelles established within the host cell cytoplasm by human-pathogenic malaria parasites and other parasites that reside within human red blood cells.
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Affiliation(s)
- Viktor Bekić
- School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Nicole Kilian
- Centre for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
- Department of Medical Biochemistry, Faculty of Basic Medical Sciences, Delta State University, Abraka, Nigeria
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3
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Pires CV, Oberstaller J, Wang C, Casandra D, Zhang M, Chawla J, Adapa SR, Otto TD, Ferdig MT, Rayner JC, Jiang RHY, Adams JH. Chemogenomic Profiling of a Plasmodium falciparum Transposon Mutant Library Reveals Shared Effects of Dihydroartemisinin and Bortezomib on Lipid Metabolism and Exported Proteins. Microbiol Spectr 2023; 11:e0501422. [PMID: 37067430 PMCID: PMC10269874 DOI: 10.1128/spectrum.05014-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 03/21/2023] [Indexed: 04/18/2023] Open
Abstract
The antimalarial activity of the frontline drug artemisinin involves generation of reactive oxygen species (ROS) leading to oxidative damage of parasite proteins. To achieve homeostasis and maintain protein quality control in the overwhelmed parasite, the ubiquitin-proteasome system kicks in. Even though molecular markers for artemisinin resistance like pfkelch13 have been identified, the intricate network of mechanisms driving resistance remains to be elucidated. Here, we report a forward genetic screening strategy that enables a broader identification of genetic factors responsible for altering sensitivity to dihydroartemisinin (DHA) and a proteasome inhibitor, bortezomib (BTZ). Using a library of isogenic piggyBac mutants in P. falciparum, we defined phenotype-genotype associations influencing drug responses and highlighted shared mechanisms between the two processes, which mainly included proteasome-mediated degradation and the lipid metabolism genes. Additional transcriptomic analysis of a DHA/BTZ-sensitive piggyBac mutant showed it is possible to find differences between the two response mechanisms on the specific components for regulation of the exportome. Our results provide further insight into the molecular mechanisms of antimalarial drug resistance. IMPORTANCE Malaria control is seriously threatened by the emergence and spread of Plasmodium falciparum resistance to the leading antimalarial, artemisinin. The potent killing activity of artemisinin results from oxidative damage unleashed by free heme activation released by hemoglobin digestion. Although the ubiquitin-proteasome system is considered critical for parasite survival of this toxicity, the diverse genetic changes linked to artemisinin resistance are complex and, so far, have not included the ubiquitin-proteasome system. In this study, we use a systematic forward genetic approach by screening a library of P. falciparum random piggyBac mutants to decipher the genetic factors driving malaria parasite responses to the oxidative stress caused by antimalarial drugs. This study compares phenotype-genotype associations influencing dihydroartemisinin responses with the proteasome inhibitor bortezomib to delineate the role of ubiquitin-proteasome system. Our study highlights shared and unique pathways from the complex array of molecular processes critical for P. falciparum survival resulting from the oxidative damage of artemisinin.
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Affiliation(s)
- Camilla Valente Pires
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Jenna Oberstaller
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Chengqi Wang
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Debora Casandra
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Min Zhang
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Jyotsna Chawla
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
| | - Swamy Rakesh Adapa
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Thomas D. Otto
- Institute of Infection, Immunity and Inflammation, MVLS, University of Glasgow, Glasgow, United Kingdom
| | - Michael T. Ferdig
- Eck Institute for Global Health, Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Julian C. Rayner
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, University of Cambridge, Cambridge, United Kingdom
| | - Rays H. Y. Jiang
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - John H. Adams
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
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4
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Beri D, Singh M, Rodriguez M, Goyal N, Rasquinha G, Liu Y, An X, Yazdanbakhsh K, Lobo CA. Global Metabolomic Profiling of Host Red Blood Cells Infected with Babesia divergens Reveals Novel Antiparasitic Target Pathways. Microbiol Spectr 2023; 11:e0468822. [PMID: 36786651 PMCID: PMC10100774 DOI: 10.1128/spectrum.04688-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/27/2023] [Indexed: 02/15/2023] Open
Abstract
Babesia divergens is an apicomplexan parasite that infects human red blood cells (RBCs), initiating cycles of invasion, replication, and egress, resulting in extensive metabolic modification of the host cells. Babesia is an auxotroph for most of the nutrients required to sustain these cycles. There are currently limited studies on the biochemical pathways that support these critical processes, necessitating the high-resolution global metabolomics approach described here to uncover the metabolic interactions between parasite and host RBC. Our results reveal an extensive parasite-mediated modulation of RBC metabolite levels of all classes, including lipids, amino acids, carbohydrates, and nucleotides, with numerous metabolic species varying in proportion to the level of infection. Many of these molecules are scavenged from the host RBCs. This is in accord with the needs of a rapidly proliferating parasite with limited biosynthetic capabilities. Probing these pathways in depth, we used growth inhibition assays to quantitate parasite susceptibility to drugs targeting these pathways and stimulated emission depletion (STED) microscopy to obtain high-resolution images of drug-treated parasites to correlate changes in morphology with specific metabolic blocks in order to validate the data generated by the untargeted metabolomics platform. Thus, interruption of cholesterol scavenging from the host cell led to premature parasite egress, while chemical targeting of the hydrolysis of acyl glycerides led to the buildup of malformed parasites that could not successfully egress. This is the first report detailing the global metabolomic profile of the B. divergens-infected RBC. Besides deciphering diverse aspects of the host-parasite relationship, our results can be exploited by others to uncover further drug targets in the host-parasite biochemical network. IMPORTANCE Human babesiosis is caused by apicomplexan parasites of the Babesia genus and is associated with transfusion-transmitted illness and relapsing disease in immunosuppressed populations. Through its continuous cycles of invasion, proliferation, and egress, B. divergens radically changes the metabolic environment of the host red blood cell, allowing us opportunities to study potential chemical vulnerabilities that can be targeted by drugs. This is the first global metabolomic profiling of Babesia-infected human red blood cells, and our analysis revealed perturbation in all biomolecular classes at levels proportional to the level of infection. In particular, lipids and energy flux pathways in the host cell were altered by infection. We validated the changes in key metabolic pathways by performing inhibition assays accompanied by high-resolution microscopy. Overall, this global metabolomics analysis of Babesia-infected red blood cells has helped to uncover novel aspects of parasite biology and identified potential biochemical pathways that can be targeted for chemotherapeutic intervention.
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Affiliation(s)
- Divya Beri
- Department of Blood-Borne Parasites, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, USA
| | - Manpreet Singh
- Department of Blood-Borne Parasites, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, USA
| | - Marilis Rodriguez
- Department of Blood-Borne Parasites, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, USA
| | - Naman Goyal
- Department of Blood-Borne Parasites, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, USA
| | | | - Yunfeng Liu
- Department of Complement Biology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, USA
| | - Xiuli An
- Department of Membrane Biology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, USA
| | - Karina Yazdanbakhsh
- Department of Complement Biology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, USA
| | - Cheryl A. Lobo
- Department of Blood-Borne Parasites, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, USA
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5
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Nuiyen A, Rattanasri A, Wipa P, Roytrakul S, Wangteeraprasert A, Pongcharoen S, Ngoenkam J. Lack of Nck1 protein and Nck-CD3 interaction caused the increment of lipid content in Jurkat T cells. BMC Mol Cell Biol 2022; 23:36. [PMID: 35902806 PMCID: PMC9330638 DOI: 10.1186/s12860-022-00436-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 07/14/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
The non-catalytic region of tyrosine kinase (Nck) is an adaptor protein, which is ubiquitously expressed in many types of cells. In T cells, the Nck1 isoform promotes T cell receptor signalling as well as actin polymerisation. However, the role of Nck1 in the lipid metabolism in T cells is unknown. In the present study, we investigated the effect of the Nck1 protein and Nck–CD3 interaction on lipid metabolism and on the physical and biological properties of Jurkat T cells, using a newly developed holotomographic microscope.
Results
Holotomographic microscopy showed that Nck1-knocked-out cells had membrane blebs and were irregular in shape compared to the rounded control cells. The cell size and volume of Nck1-deficient cells were comparable to those of the control cells. Nck1-knocked-out Jurkat T cells had a greater lipid content, lipid mass/cell mass ratio, and lipid metabolite levels than the control cells. Interestingly, treatment with a small molecule, AX-024, which inhibited Nck–CD3 interaction, also caused an increase in the lipid content in wild-type Jurkat T cells, as found in Nck1-deficient cells.
Conclusions
Knockout of Nck1 protein and hindrance of the Nck–CD3 interaction cause the elevation of lipid content in Jurkat T cells.
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6
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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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7
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Hayakawa ESH, Wayama M, Tokumasu F, Ohno N, Matsumoto M, Usukura J. Budding pouches and associated bubbles: 3D visualization of exo-membrane structures in plasmodium falciparum gametocytes. Front Cell Infect Microbiol 2022; 12:962495. [PMID: 36072224 PMCID: PMC9441640 DOI: 10.3389/fcimb.2022.962495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 08/02/2022] [Indexed: 11/16/2022] Open
Abstract
Plasmodium falciparum gametocytes have unique morphology, metabolism, and protein expression profiles in their asexual stages of development. In addition to the striking changes in their appearance, a wide variety of “exo-membrane structures” are newly formed in the gametocyte stage. Little is known about their function, localization, or three-dimensional structural information, and only some structural data, typically two-dimensional, have been reported using conventional electron microscopy or fluorescence microscopy. For better visualization of intracellular organelle and exo-membrane structures, we previously established an unroofing technique to directly observe Maurer’s clefts (MCs) in asexual parasitized erythrocytes by removing the top part of the cell’s membrane followed by transmission electron microscopy. We found that MCs have numerous tethers connecting themselves to the host erythrocyte membrane skeletons. In this study, we investigated the intracellular structures of gametocytes using unroofing-TEM, Serial Block Face scanning electron microscopy, and fluorescence microscopy to unveil the exo-membrane structures in gametocytes. Our data showed “balloon/pouch”-like objects budding from the parasitophorous vacuole membrane (PVM) in gametocytes, and some balloons included multiple layers of other balloons. Furthermore, numerous bubbles appeared on the inner surface of the erythrocyte membrane or PVM; these were similar to MC-like membranes but were smaller than asexual MCs. Our study demonstrated P. falciparum reforms exo-membranes in erythrocytes to meet stage-specific biological activities during their sexual development.
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Affiliation(s)
- Eri Saki H. Hayakawa
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
- *Correspondence: Eri Saki H. Hayakawa, ; Fuyuki Tokumasu,
| | - Marina Wayama
- Nanostructure Characterization Group, Solution Development Department, Hitachi High-Tech Corporation, Tokyo, Japan
| | - Fuyuki Tokumasu
- Department of Cellular Architecture Studies, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan
- *Correspondence: Eri Saki H. Hayakawa, ; Fuyuki Tokumasu,
| | - Nobuhiko Ohno
- Division of Histology and Cell Biology, Department of Anatomy, Jichi Medical University, Tochigi, Japan
- Division of Ultrastructural Research, National Institute for Physiological Sciences, Okazaki, Japan
| | - Mami Matsumoto
- Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological Sciences, Okazaki, Japan
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Jiro Usukura
- Institute of Material and Systems for Sustainability, Nagoya University, Nagoya, Japan
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8
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Shunmugam S, Arnold CS, Dass S, Katris NJ, Botté CY. The flexibility of Apicomplexa parasites in lipid metabolism. PLoS Pathog 2022; 18:e1010313. [PMID: 35298557 PMCID: PMC8929637 DOI: 10.1371/journal.ppat.1010313] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Apicomplexa are obligate intracellular parasites responsible for major human infectious diseases such as toxoplasmosis and malaria, which pose social and economic burdens around the world. To survive and propagate, these parasites need to acquire a significant number of essential biomolecules from their hosts. Among these biomolecules, lipids are a key metabolite required for parasite membrane biogenesis, signaling events, and energy storage. Parasites can either scavenge lipids from their host or synthesize them de novo in a relict plastid, the apicoplast. During their complex life cycle (sexual/asexual/dormant), Apicomplexa infect a large variety of cells and their metabolic flexibility allows them to adapt to different host environments such as low/high fat content or low/high sugar levels. In this review, we discuss the role of lipids in Apicomplexa parasites and summarize recent findings on the metabolic mechanisms in host nutrient adaptation.
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Affiliation(s)
- Serena Shunmugam
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
| | - Christophe-Sébastien Arnold
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
| | - Sheena Dass
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
| | - Nicholas J. Katris
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
| | - Cyrille Y. Botté
- Apicolipid Team, Institute for Advanced Biosciences, CNRS UMR5309, Université Grenoble Alpes, INSERM U1209, Grenoble, France
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9
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Ahiya AI, Bhatnagar S, Morrisey JM, Beck JR, Vaidya AB. Dramatic Consequences of Reducing Erythrocyte Membrane Cholesterol on Plasmodium falciparum. Microbiol Spectr 2022; 10:e0015822. [PMID: 35196803 PMCID: PMC8865471 DOI: 10.1128/spectrum.00158-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 02/01/2022] [Indexed: 01/11/2023] Open
Abstract
Cholesterol is the most abundant lipid in the erythrocyte. During its blood-stage development, the malaria parasite establishes an active cholesterol gradient across the various membrane systems within the infected erythrocyte. Interestingly, some antimalarial compounds have recently been shown to disrupt cholesterol homeostasis in the intraerythrocytic stages of Plasmodium falciparum. These studies point to the importance of cholesterol for parasite growth. Previously, reduction of cholesterol from the erythrocyte membrane by treatment with methyl-β-cyclodextrin (MβCD) was shown to inhibit parasite invasion and growth. In addition, MβCD treatment of trophozoite-stage P. falciparum was shown to result in parasite expulsion from the host cell. We have revisited these phenomena by using live video microscopy, ultrastructural analysis, and response to antimalarial compounds. By using time-lapse video microscopy of fluorescently tagged parasites, we show that MβCD treatment for just 30 min causes dramatic expulsion of the trophozoite-stage parasites. This forceful expulsion occurs within 10 s. Remarkably, the plasma membrane of the host cell from which the parasite has been expelled does not appear to be compromised. The parasitophorous vacuolar membrane (PVM) continued to surround the extruded parasite, but the PVM appeared damaged. Treatment with antimalarial compounds targeting PfATP4 or PfNCR1 prevented MβCD-mediated extrusion of the parasites, pointing to a potential role of cholesterol dynamics underlying the expulsion phenomena. We also confirmed the essential role of erythrocyte plasma membrane cholesterol for invasion and growth of P. falciparum. This defect can be partially complemented by cholesterol and desmosterol but not with epicholesterol, revealing stereospecificity underlying cholesterol function. Overall, our studies advance previous observations and reveal unusual cell biological features underlying cholesterol depletion of the infected erythrocyte plasma membrane. IMPORTANCE Malaria remains a major challenge in much of the world. Symptoms of malaria are caused by the growth of parasites belonging to Plasmodium spp. inside the red blood cells (RBCs), leading to their destruction. The parasite depends upon its host for much of its nutritional needs. Cholesterol is a major lipid in the RBC plasma membrane, which is the only source of this lipid for malaria parasites. We have previously shown that certain new antimalarial compounds disrupt cholesterol homeostasis in P. falciparum. Here, we use live time-lapse video microscopy to show dramatic expulsion of the parasite from the host RBC when the cholesterol content of the RBC is reduced. Remarkably, this expulsion is inhibited by the antimalarials that disrupt lipid homeostasis. We also show stereospecificity of cholesterol in supporting parasite growth inside RBC. Overall, these results point to a critical role of cholesterol in the physiology of malaria parasites.
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Affiliation(s)
- Avantika I. Ahiya
- Center for Molecular Parasitology, Institute for Molecular Medicine and Infectious Disease, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Suyash Bhatnagar
- Center for Molecular Parasitology, Institute for Molecular Medicine and Infectious Disease, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Joanne M. Morrisey
- Center for Molecular Parasitology, Institute for Molecular Medicine and Infectious Disease, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Josh R. Beck
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, USA
| | - Akhil B. Vaidya
- Center for Molecular Parasitology, Institute for Molecular Medicine and Infectious Disease, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
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10
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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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11
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Malwal SR, Oldfield E. Mycobacterial membrane protein Large 3-like-family proteins in bacteria, protozoa, fungi, plants, and animals: A bioinformatics and structural investigation. Proteins 2021; 90:776-790. [PMID: 34739144 DOI: 10.1002/prot.26273] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/25/2021] [Indexed: 01/20/2023]
Abstract
Lipid transporters play an important role in most if not all organisms, ranging from bacteria to humans. For example, in Mycobacterium tuberculosis, the trehalose monomycolate transporter MmpL3 is involved in cell wall biosynthesis, while in humans, cholesterol transporters are involved in normal cell function as well as in disease. Here, using structural and bioinformatics information, we propose that there are proteins that also contain "MmpL3-like" (MMPL) transmembrane (TM) domains in many protozoa, including Trypanosoma cruzi, as well as in the bacterium Staphylococcus aureus, where the fatty acid transporter FarE has the same set of "active-site" residues as those found in the mycobacterial MmpL3s, and in T. cruzi. We also show that there are strong sequence and predicted structural similarities between the TM proton-translocation domain seen in the X-ray structures of mycobacterial MmpL3s and several human as well as fungal lipid transporters, leading to the proposal that there are similar proteins in apicomplexan parasites, and in plants. The animal, fungal, apicomplexan, and plant proteins have larger extra-membrane domains than are found in the bacterial MmpL3, but they have a similar TM domain architecture, with the introduction of a (catalytically essential) Phe > His residue change, and a Ser/Thr H-bond network, involved in H+ -transport. Overall, the results are of interest since they show that MMPL-family proteins are present in essentially all life forms: archaea, bacteria, protozoa, fungi, plants and animals and, where known, they are involved in "lipid" (glycolipid, phospholipid, sphingolipid, fatty acid, cholesterol, ergosterol) transport, powered by transmembrane molecular pumps having similar structures.
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Affiliation(s)
- Satish R Malwal
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Eric Oldfield
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
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12
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Ressurreição M, van Ooij C. Lipid transport proteins in malaria, from Plasmodium parasites to their hosts. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:159047. [PMID: 34461309 DOI: 10.1016/j.bbalip.2021.159047] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 08/08/2021] [Accepted: 08/10/2021] [Indexed: 11/25/2022]
Abstract
Eukaryotic unicellular pathogens from the genus Plasmodium are the etiological agents of malaria, a disease that persists over a wide range of vertebrate species, including humans. During its dynamic lifecycle, survival in the different hosts depends on the parasite's ability to establish a suitable environmental milieu. To achieve this, specific host processes are exploited to support optimal growth, including extensive modifications to the infected host cell. These modifications include the formation of novel membranous structures, which are induced by the parasite. Consequently, to maintain a finely tuned and dynamic lipid environment, the organisation and distribution of lipids to different cell sites likely requires specialised lipid transfer proteins (LTPs). Indeed, several parasite and host-derived LTPs have been identified and shown to be essential at specific stages. Here we describe the roles of LTPs in parasite development and adaptation to its host including how the latest studies are profiting from the improved genetic, lipidomic and imaging toolkits available to study Plasmodium parasites. Lastly, a list of predicted Plasmodium LTPs is provided to encourage research in this field.
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Affiliation(s)
- Margarida Ressurreição
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom.
| | - Christiaan van Ooij
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom.
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13
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Ezetimibe blocks Toxoplasma gondii-, Neospora caninum- and Besnoitia besnoiti-tachyzoite infectivity and replication in primary bovine endothelial host cells. Parasitology 2021; 148:1107-1115. [PMID: 34024307 PMCID: PMC8273898 DOI: 10.1017/s0031182021000822] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Coccidia are obligate apicomplexan parasites that affect humans and animals. In fast replicating species, in vitro merogony takes only 24–48 h. In this context, successful parasite proliferation requires nutrients and other building blocks. Coccidian parasites are auxotrophic for cholesterol, so they need to obtain this molecule from host cells. In humans, ezetimibe has been applied successfully as hypolipidaemic compound, since it reduces intestinal cholesterol absorption via blockage of Niemann−Pick C-1 like-1 protein (NPC1L1), a transmembrane protein expressed in enterocytes. To date, few data are available on its potential anti-parasitic effects in primary host cells infected with apicomplexan parasites of human and veterinary importance, such as Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti. Current inhibition experiments show that ezetimibe effectively blocks T. gondii, B. besnoiti and N. caninum tachyzoite infectivity and replication in primary bovine endothelial host cells. Thus, 20 μm ezetimibe blocked parasite proliferation by 73.1−99.2%, via marked reduction of the number of tachyzoites per meront, confirmed by 3D-holotomographic analyses. The effects were parasitostatic since withdrawal of the compound led to parasite recovery with resumed proliferation. Ezetimibe-glucuronide, the in vivo most effective metabolite, failed to affect parasite proliferation in vitro, thereby suggesting that ezetimibe effects might be NPC1L1-independent.
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14
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Jonsdottir TK, Gabriela M, Crabb BS, F de Koning-Ward T, Gilson PR. Defining the Essential Exportome of the Malaria Parasite. Trends Parasitol 2021; 37:664-675. [PMID: 33985912 DOI: 10.1016/j.pt.2021.04.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/15/2021] [Accepted: 04/15/2021] [Indexed: 02/06/2023]
Abstract
To survive inside red blood cells (RBCs), malaria parasites export many proteins to alter their host cell's physiological properties. Although most proteins of this exportome are involved in immune avoidance or in the trafficking of exported proteins to the host membrane, about 20% are essential for parasite survival in culture but little is known about their biological functions. Here, we have combined information from large-scale genetic screens and targeted gene-disruption studies to tabulate all currently known Plasmodium falciparum exported proteins according to their likelihood of being essential. We also discuss the essential functional pathways that exported proteins might be involved in to help direct research efforts towards a more comprehensive understanding of host-cell remodelling.
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Affiliation(s)
- Thorey K Jonsdottir
- Burnet Institute, Melbourne, Victoria 3004, Australia; Department of Microbiology and Immunology, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Mikha Gabriela
- Burnet Institute, Melbourne, Victoria 3004, Australia; School of Medicine, Deakin University, Waurn Ponds, Victoria 3216, Australia
| | - Brendan S Crabb
- Burnet Institute, Melbourne, Victoria 3004, Australia; Department of Microbiology and Immunology, University of Melbourne, Melbourne, Victoria 3010, Australia
| | | | - Paul R Gilson
- Burnet Institute, Melbourne, Victoria 3004, Australia.
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15
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Creative interior design by Plasmodium falciparum: Lipid metabolism and the parasite's secret chamber. Parasitol Int 2021; 83:102369. [PMID: 33905815 DOI: 10.1016/j.parint.2021.102369] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/06/2021] [Accepted: 04/20/2021] [Indexed: 11/21/2022]
Abstract
Malaria parasites conceal themselves within host erythrocytes and establish a necessary logistics system through the three-membrane layered structures of these cells. To establish this system, lipid metabolism is needed for the de novo synthesis of lipids and the recycling of extracellular lipids and erythrocyte lipid components. Cholesterol supply depends on its uptake from the extracellular environment and erythrocyte cytoplasm, but phospholipids can be synthesized on their own. This differential production of lipid species creates unique modifications in the lipid profile of parasitized erythrocytes, which in turn may influence the biophysical and/or mechanical properties of organelles and vesicles and communication among them. Variations in local membrane properties possibly influence the transportation of various molecules such as parasite-derived proteins, because efficiencies in secretion, vesicle fusion and budding are partly determined by the lipid profiles. Comprehensive understanding of the parasite's lipid metabolism and the biophysics of lipid membranes provides fundamental knowledge about these pathogenic organisms and could lead to new anti-malarials.
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16
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Fraser M, Jing W, Bröer S, Kurth F, Sander LE, Matuschewski K, Maier AG. Breakdown in membrane asymmetry regulation leads to monocyte recognition of P. falciparum-infected red blood cells. PLoS Pathog 2021; 17:e1009259. [PMID: 33600495 PMCID: PMC7891792 DOI: 10.1371/journal.ppat.1009259] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/28/2020] [Indexed: 02/06/2023] Open
Abstract
The human malaria parasite Plasmodium falciparum relies on lipids to survive; this makes its lipid metabolism an attractive drug target. The lipid phosphatidylserine (PS) is usually confined to the inner leaflet of the red blood cell membrane (RBC) bilayer; however, some studies suggest that infection with the intracellular parasite results in the presence of this lipid in the RBC membrane outer leaflet, where it could act as a recognition signal to phagocytes. Here, we used fluorescent lipid analogues and probes to investigate the enzymatic reactions responsible for maintaining asymmetry between membrane leaflets, and found that in parasitised RBCs the maintenance of membrane asymmetry was partly disrupted, and PS was increased in the outer leaflet. We examined the underlying causes for the differences between uninfected and infected RBCs using fluorescent dyes and probes, and found that calcium levels increased in the infected RBC cytoplasm, whereas membrane cholesterol was depleted from the erythrocyte plasma membrane. We explored the resulting effect of PS exposure on enhanced phagocytosis by monocytes, and show that infected RBCs must expend energy to limit phagocyte recognition, and provide experimental evidence that PS exposure contributes to phagocytic recognition of P. falciparum-infected RBCs. Together, these findings underscore the pivotal role for PS exposure on the surface of Plasmodium falciparum-infected erythrocytes for in vivo interactions with the host immune system, and provide a rationale for targeted antimalarial drug design.
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Affiliation(s)
- Merryn Fraser
- Research School of Biology, The Australian National University, Canberra, Australia
- Department of Molecular Parasitology, Institute of Biology, Humboldt University, Berlin, Germany
| | - Weidong Jing
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Stefan Bröer
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Florian Kurth
- Department of Infectious Diseases and Pulmonary Medicine, Charité-Universitätsmedizin Berlin, Germany
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- Department of Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Leif-Erik Sander
- Department of Infectious Diseases and Pulmonary Medicine, Charité-Universitätsmedizin Berlin, Germany
| | - Kai Matuschewski
- Department of Molecular Parasitology, Institute of Biology, Humboldt University, Berlin, Germany
| | - Alexander G. Maier
- Research School of Biology, The Australian National University, Canberra, Australia
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Usman MA, Ibrahim MA, Salman AA, Sallau AB. Depletion of cholesterol could be associated with modulation of progesterone but not other sex hormone levels during Plasmodium falciparum infection in humans: a cross-sectional study from Zaria, Nigeria. Parasitol Res 2020; 119:4143-4150. [PMID: 32951142 DOI: 10.1007/s00436-020-06826-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 07/21/2020] [Indexed: 10/23/2022]
Abstract
In order for Plasmodium falciparum to grow and survive in its host, membrane biogenesis, fueled by host cholesterol, is essential for these processes. Consistent with this essential role, more insights into the cholesterol pathway would enhance the current understanding of the pathophysiology of malaria infection. To explore its broader potential, we conducted a cross-sectional study and assayed for the serum levels of cholesterol, vitamin D, progesterone, testosterone, estradiol and bile acid in both P. falciparum-infected patients and apparently healthy sex-matched participants. Our results revealed that the levels of cholesterol, vitamin D, progesterone, testosterone and estradiol in P. falciparum-infected patients were significantly (p < 0.05) lower compared to those in control groups whereas the level of bile acid in P. falciparum-infected patients was significantly (p < 0.05) higher compared to that in control groups. Additionally, cholesterol and the metabolic products with the exception of bile acid had a significant (p < 0.05) association with the parasite density in P. falciparum-infected patients with moderate and high P. falciparum infections. Furthermore, all the metabolic products of cholesterol had an insignificant (p > 0.05) association with the cholesterol in P. falciparum-infected patients with the exception of progesterone which showed a significant (p < 0.05) association with cholesterol in the malaria-infected female patients. Data from the present study demonstrated that progesterone depletion in P. falciparum-infected female patients could be a consequence of P. falciparum-induced decrease in cholesterol.
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18
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Hayakawa EH, Kato H, Nardone GA, Usukura J. A prospective mechanism and source of cholesterol uptake by Plasmodium falciparum-infected erythrocytes co-cultured with HepG2 cells. Parasitol Int 2020; 80:102179. [PMID: 32853776 DOI: 10.1016/j.parint.2020.102179] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 06/23/2020] [Accepted: 07/20/2020] [Indexed: 12/17/2022]
Abstract
Plasmodium falciparum (P. falciparum) parasites still cause lethal infections worldwide, especially in Africa (https://www.who.int/publications/i/item/world-malaria-report-2019). During P. falciparum blood-stage infections in humans, low-density lipoprotein, high-density lipoprotein and cholesterol levels in the blood become low. Because P. falciparum lacks a de novo cholesterol synthesis pathway, it must import cholesterol from the surrounding environment. However, the origin of the cholesterol and how it is taken up by the parasite across the multiple membranes that surround it is not fully understood. To answer this, we used a cholesterol synthesis inhibiter (simvastatin), a cholesterol transport inhibitor (ezetimibe), and an activating ligand of the peroxisome proliferator-activated receptor α, called ciprofibrate, to investigate the effects of these agents on the intraerythrocytic growth of P. falciparum, both with and without HepG2 cells as the lipoprotein feeders. P. falciparum growth was inhibited in the presence of ezetimibe, but ezetimibe was not very effective at inhibiting P. falciparum growth when used in the co-culture system, unlike simvastatin, which strongly promoted parasite growth in this system. Ezetimibe is known to inhibit cholesterol absorption by blocking the activity of Niemann-Pick C1 like 1 (NPC1L1) protein, and simvastatin is known to enhance NPC1L1 expression in the human body's small intestine. Collectively, our results support the possibility that cholesterol import by P. falciparum involves hepatocytes, and cholesterol uptake into the parasite occurs via NPC1L1 protein or an NPC1L1 homolog during the erythrocytic stages of the P. falciparum lifecycle.
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Affiliation(s)
- Eri H Hayakawa
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke, Tochigi 329-0498, Japan.
| | - Hirotomo Kato
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke, Tochigi 329-0498, Japan
| | - Glenn A Nardone
- Research Technology Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-5766, USA
| | - Jiro Usukura
- Institute of Material and Systems for Sustainability, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
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