1
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Wu Y, Pernet E, Touqui L. Modulation of Airway Expression of the Host Bactericidal Enzyme, sPLA2-IIA, by Bacterial Toxins. Toxins (Basel) 2023; 15:440. [PMID: 37505708 PMCID: PMC10467128 DOI: 10.3390/toxins15070440] [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: 04/13/2023] [Revised: 06/23/2023] [Accepted: 06/29/2023] [Indexed: 07/29/2023] Open
Abstract
Host molecules with antimicrobial properties belong to a large family of mediators including type-IIA secreted phospholipase A2 (sPLA2-IIA). The latter is a potent bactericidal agent with high selectivity against Gram-positive bacteria, but it may also play a role in modulating the host inflammatory response. However, several pathogen-associated molecular patterns (PAMPs) or toxins produced by pathogenic bacteria can modulate the levels of sPLA2-IIA by either inducing or inhibiting its expression in host cells. Thus, the final sPLA2-IIA concentration during the infection process is determined by the orchestration between the levels of toxins that stimulate and those that downregulate the expression of this enzyme. The stimulation of sPLA2-IIA expression is a process that participates in the clearance of invading bacteria, while inhibition of this expression highlights a mechanism by which certain bacteria can subvert the immune response and invade the host. Here, we will review the major functions of sPLA2-IIA in the airways and the role of bacterial toxins in modulating the expression of this enzyme. We will also summarize the major mechanisms involved in this modulation and the potential consequences for the pulmonary host response to bacterial infection.
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Affiliation(s)
- Yongzheng Wu
- Unité de Biologie Cellulaire de l’Infection Microbionne, CNRS UMR3691, Institut Pasteur, Université de Paris Cité, 75015 Paris, France;
| | - Erwan Pernet
- Groupe de Recherche en Signalisation Cellulaire, Département de Biologie Médicale, Université du Québec à Trois-Rivières, Trois-Rivières, QC G8Z 4M3, Canada
| | - Lhousseine Touqui
- Sorbonne Université, Inserm U938, Centre de Recherche Saint-Antoine (CRSA), 75012 Paris, France
- Institut Pasteur, Université de Paris Cité, Mucoviscidose et Bronchopathies Chroniques, 75015 Paris, France
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2
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Doré E, Joly-Beauparlant C, Morozumi S, Mathieu A, Lévesque T, Allaeys I, Duchez AC, Cloutier N, Leclercq M, Bodein A, Payré C, Martin C, Petit-Paitel A, Gelb MH, Rangachari M, Murakami M, Davidovic L, Flamand N, Arita M, Lambeau G, Droit A, Boilard E. The interaction of secreted phospholipase A2-IIA with the microbiota alters its lipidome and promotes inflammation. JCI Insight 2022; 7:152638. [PMID: 35076027 PMCID: PMC8855825 DOI: 10.1172/jci.insight.152638] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 12/01/2021] [Indexed: 12/13/2022] Open
Abstract
Secreted phospholipase A2-IIA (sPLA2-IIA) hydrolyzes phospholipids to liberate lysophospholipids and fatty acids. Given its poor activity toward eukaryotic cell membranes, its role in the generation of proinflammatory lipid mediators is unclear. Conversely, sPLA2-IIA efficiently hydrolyzes bacterial membranes. Here, we show that sPLA2-IIA affects the immune system by acting on the intestinal microbial flora. Using mice overexpressing transgene-driven human sPLA2-IIA, we found that the intestinal microbiota was critical for both induction of an immune phenotype and promotion of inflammatory arthritis. The expression of sPLA2-IIA led to alterations of the intestinal microbiota composition, but housing in a more stringent pathogen-free facility revealed that its expression could affect the immune system in the absence of changes to the composition of this flora. In contrast, untargeted lipidomic analysis focusing on bacteria-derived lipid mediators revealed that sPLA2-IIA could profoundly alter the fecal lipidome. The data suggest that a singular protein, sPLA2-IIA, produces systemic effects on the immune system through its activity on the microbiota and its lipidome.
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Affiliation(s)
- Etienne Doré
- CHU de Québec-Université Laval Research Center, Department of Microbiology, Infectiology and Immunology, Quebec City, Quebec, Canada
- ARThrite Research Center, University Laval, Quebec City, Quebec, Canada
| | - Charles Joly-Beauparlant
- CHU de Québec-Université Laval Research Center, Endocrinology and Nephrology Axis, Quebec City, Quebec, Canada
| | - Satoshi Morozumi
- Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
- Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan
| | - Alban Mathieu
- CHU de Québec-Université Laval Research Center, Endocrinology and Nephrology Axis, Quebec City, Quebec, Canada
| | - Tania Lévesque
- CHU de Québec-Université Laval Research Center, Department of Microbiology, Infectiology and Immunology, Quebec City, Quebec, Canada
- ARThrite Research Center, University Laval, Quebec City, Quebec, Canada
| | - Isabelle Allaeys
- CHU de Québec-Université Laval Research Center, Department of Microbiology, Infectiology and Immunology, Quebec City, Quebec, Canada
- ARThrite Research Center, University Laval, Quebec City, Quebec, Canada
| | - Anne-Claire Duchez
- CHU de Québec-Université Laval Research Center, Department of Microbiology, Infectiology and Immunology, Quebec City, Quebec, Canada
| | - Nathalie Cloutier
- CHU de Québec-Université Laval Research Center, Department of Microbiology, Infectiology and Immunology, Quebec City, Quebec, Canada
| | - Mickaël Leclercq
- CHU de Québec-Université Laval Research Center, Endocrinology and Nephrology Axis, Quebec City, Quebec, Canada
| | - Antoine Bodein
- CHU de Québec-Université Laval Research Center, Endocrinology and Nephrology Axis, Quebec City, Quebec, Canada
| | - Christine Payré
- Côte d’Azur University, The French National Centre for Scientific Research, Institute of Molecular and Cellular Pharmacology, UMR7275, Valbonne Sophia Antipolis, France
| | - Cyril Martin
- The Research Center of the University Institute of Cardiology and Pneumology of Quebec, Quebec City, Quebec, Canada
| | - Agnes Petit-Paitel
- Côte d’Azur University, The French National Centre for Scientific Research, Institute of Molecular and Cellular Pharmacology, UMR7275, Valbonne Sophia Antipolis, France
| | - Michael H. Gelb
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| | - Manu Rangachari
- CHU de Québec-Université Laval Research Center, Neurosciences Axis, Quebec City, Quebec, Canada
| | - Makoto Murakami
- Laboratory of Microenvironmental and Metabolic Health Science, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Laetitia Davidovic
- Côte d’Azur University, The French National Centre for Scientific Research, Institute of Molecular and Cellular Pharmacology, UMR7275, Valbonne Sophia Antipolis, France
| | - Nicolas Flamand
- ARThrite Research Center, University Laval, Quebec City, Quebec, Canada
- The Research Center of the University Institute of Cardiology and Pneumology of Quebec, Quebec City, Quebec, Canada
| | - Makoto Arita
- Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
- Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan
- Cellular and Molecular Epigenetics Laboratory, Graduate School of Medical Life Science, Yokohama-City University, Yokohama, Japan
| | - Gérard Lambeau
- Côte d’Azur University, The French National Centre for Scientific Research, Institute of Molecular and Cellular Pharmacology, UMR7275, Valbonne Sophia Antipolis, France
| | - Arnaud Droit
- CHU de Québec-Université Laval Research Center, Endocrinology and Nephrology Axis, Quebec City, Quebec, Canada
| | - Eric Boilard
- CHU de Québec-Université Laval Research Center, Department of Microbiology, Infectiology and Immunology, Quebec City, Quebec, Canada
- ARThrite Research Center, University Laval, Quebec City, Quebec, Canada
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3
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Pungerčar J, Bihl F, Lambeau G, Križaj I. What do secreted phospholipases A 2 have to offer in combat against different viruses up to SARS-CoV-2? Biochimie 2021; 189:40-50. [PMID: 34097986 PMCID: PMC8449419 DOI: 10.1016/j.biochi.2021.05.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 05/24/2021] [Accepted: 05/31/2021] [Indexed: 12/09/2022]
Abstract
Secreted phospholipases A2 (sPLA2s) form a widespread group of structurally-related enzymes that catalyse the hydrolysis of the sn-2 ester bond of glycerophospholipids to produce free fatty acids and lysophospholipids. In humans, nine catalytically active and two inactive sPLA2 proteins have been identified. These enzymes play diverse biological roles, including host defence against bacteria, parasites and viruses. Several of these endogenous sPLA2s may play a defensive role in viral infections, as they display in vitro antiviral activity by both direct and indirect mechanisms. However, endogenous sPLA2s may also exert an offensive and negative role, dampening the antiviral response or promoting inflammation in animal models of viral infection. Similarly, several exogenous sPLA2s, most of them from snake venoms and other animal venoms, possess in vitro antiviral activities. Thus, both endogenous and exogenous sPLA2s may be exploited for the development of new antiviral substances or as therapeutic targets for antagonistic drugs that may promote a more robust antiviral response. In this review, the antiviral versus proviral role of both endogenous and exogenous sPLA2s against various viruses including coronaviruses is presented. Based on the highlighted developments in this area of research, possible directions of future investigation are envisaged. One of them is also a possibility of exploiting sPLA2s as biological markers of the severity of the Covid-19 pandemic caused by SARS-CoV-2 infection.
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Affiliation(s)
- Jože Pungerčar
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana, Slovenia.
| | - Franck Bihl
- Université Côte d'Azur (UCA), Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR7275, Valbonne Sophia Antipolis, France
| | - Gérard Lambeau
- Université Côte d'Azur (UCA), Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR7275, Valbonne Sophia Antipolis, France.
| | - Igor Križaj
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana, Slovenia.
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4
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Pidwill GR, Gibson JF, Cole J, Renshaw SA, Foster SJ. The Role of Macrophages in Staphylococcus aureus Infection. Front Immunol 2021; 11:620339. [PMID: 33542723 PMCID: PMC7850989 DOI: 10.3389/fimmu.2020.620339] [Citation(s) in RCA: 137] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 12/02/2020] [Indexed: 12/23/2022] Open
Abstract
Staphylococcus aureus is a member of the human commensal microflora that exists, apparently benignly, at multiple sites on the host. However, as an opportunist pathogen it can also cause a range of serious diseases. This requires an ability to circumvent the innate immune system to establish an infection. Professional phagocytes, primarily macrophages and neutrophils, are key innate immune cells which interact with S. aureus, acting as gatekeepers to contain and resolve infection. Recent studies have highlighted the important roles of macrophages during S. aureus infections, using a wide array of killing mechanisms. In defense, S. aureus has evolved multiple strategies to survive within, manipulate and escape from macrophages, allowing them to not only subvert but also exploit this key element of our immune system. Macrophage-S. aureus interactions are multifaceted and have direct roles in infection outcome. In depth understanding of these host-pathogen interactions may be useful for future therapeutic developments. This review examines macrophage interactions with S. aureus throughout all stages of infection, with special emphasis on mechanisms that determine infection outcome.
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Affiliation(s)
- Grace R. Pidwill
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
| | - Josie F. Gibson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Joby Cole
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
| | - Stephen A. Renshaw
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, University of Sheffield, Sheffield, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
| | - Simon J. Foster
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
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5
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Souza BBP, Cardozo Fh JL, Murad AM, Prates MV, Coura MM, Brand GD, Barbosa EA, Bloch C. Identification and characterization of phospholipases A2 from the skin secretion of Pithecopus azureus anuran. Toxicon 2019; 167:10-19. [DOI: 10.1016/j.toxicon.2019.06.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/17/2019] [Accepted: 06/03/2019] [Indexed: 11/26/2022]
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6
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van Hensbergen VP, Movert E, de Maat V, Lüchtenborg C, Le Breton Y, Lambeau G, Payré C, Henningham A, Nizet V, van Strijp JAG, Brügger B, Carlsson F, McIver KS, van Sorge NM. Streptococcal Lancefield polysaccharides are critical cell wall determinants for human Group IIA secreted phospholipase A2 to exert its bactericidal effects. PLoS Pathog 2018; 14:e1007348. [PMID: 30321240 PMCID: PMC6201954 DOI: 10.1371/journal.ppat.1007348] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 10/25/2018] [Accepted: 09/20/2018] [Indexed: 12/21/2022] Open
Abstract
Human Group IIA secreted phospholipase A2 (hGIIA) is an acute phase protein with bactericidal activity against Gram-positive bacteria. Infection models in hGIIA transgenic mice have suggested the importance of hGIIA as an innate defense mechanism against the human pathogens Group A Streptococcus (GAS) and Group B Streptococcus (GBS). Compared to other Gram-positive bacteria, GAS is remarkably resistant to hGIIA activity. To identify GAS resistance mechanisms, we exposed a highly saturated GAS M1 transposon library to recombinant hGIIA and compared relative mutant abundance with library input through transposon-sequencing (Tn-seq). Based on transposon prevalence in the output library, we identified nine genes, including dltA and lytR, conferring increased hGIIA susceptibility. In addition, seven genes conferred increased hGIIA resistance, which included two genes, gacH and gacI that are located within the Group A Carbohydrate (GAC) gene cluster. Using GAS 5448 wild-type and the isogenic gacI mutant and gacI-complemented strains, we demonstrate that loss of the GAC N-acetylglucosamine (GlcNAc) side chain in the ΔgacI mutant increases hGIIA resistance approximately 10-fold, a phenotype that is conserved across different GAS serotypes. Increased resistance is associated with delayed penetration of hGIIA through the cell wall. Correspondingly, loss of the Lancefield Group B Carbohydrate (GBC) rendered GBS significantly more resistant to hGIIA-mediated killing. This suggests that the streptococcal Lancefield antigens, which are critical determinants for streptococcal physiology and virulence, are required for the bactericidal enzyme hGIIA to exert its bactericidal function.
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Affiliation(s)
- Vincent P. van Hensbergen
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Elin Movert
- Department of Experimental Medical Science, Section for Immunology, Lund University, Lund, Sweden
| | - Vincent de Maat
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | | | - Yoann Le Breton
- Department of Cell Biology & Molecular Genetics and Maryland Pathogen Research Institute, University of Maryland, College Park, MD, United States of America
| | - Gérard Lambeau
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Department of Biochemistry, Valbonne, France
| | - Christine Payré
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Department of Biochemistry, Valbonne, France
| | - Anna Henningham
- Department of Pediatrics and Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Victor Nizet
- Department of Pediatrics and Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
- Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Jos A. G. van Strijp
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Britta Brügger
- Heidelberg University, Biochemistry Center (BZH), Heidelberg, Germany
| | - Fredric Carlsson
- Department of Experimental Medical Science, Section for Immunology, Lund University, Lund, Sweden
- Department of Biology, Section for Molecular Cell Biology, Lund University, Lund, Sweden
| | - Kevin S. McIver
- Department of Cell Biology & Molecular Genetics and Maryland Pathogen Research Institute, University of Maryland, College Park, MD, United States of America
| | - Nina M. van Sorge
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
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7
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Dore E, Boilard E. Roles of secreted phospholipase A 2 group IIA in inflammation and host defense. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:789-802. [PMID: 30905346 DOI: 10.1016/j.bbalip.2018.08.017] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 08/29/2018] [Accepted: 08/30/2018] [Indexed: 01/08/2023]
Abstract
Among all members of the secreted phospholipase A2 (sPLA2) family, group IIA sPLA2 (sPLA2-IIA) is possibly the most studied enzyme. Since its discovery, many names have been associated with sPLA2-IIA, such as "non-pancreatic", "synovial", "platelet-type", "inflammatory", and "bactericidal" sPLA2. Whereas the different designations indicate comprehensive functions or sources proposed for this enzyme, the identification of the precise roles of sPLA2-IIA has remained a challenge. This can be attributed to: the expression of the enzyme by various cells of different lineages, its limited activity towards the membranes of immune cells despite its expression following common inflammatory stimuli, its ability to interact with certain proteins independently of its catalytic activity, and its absence from multiple commonly used mouse models. Nevertheless, elevated levels of the enzyme during inflammatory processes and associated consistent release of arachidonic acid from the membrane of extracellular vesicles suggest that sPLA2-IIA may contribute to inflammation by using endogenous substrates in the extracellular milieu. Moreover, the remarkable potency of sPLA2-IIA towards bacterial membranes and its induced expression during the course of infections point to a role for this enzyme in the defense of the host against invading pathogens. In this review, we present current knowledge related to mammalian sPLA2-IIA and its roles in sterile inflammation and host defense.
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Affiliation(s)
- Etienne Dore
- Centre de Recherche du CHU de Québec, Université Laval, Department of Infectious Diseases and Immunity, Québec City, QC, Canada
| | - Eric Boilard
- Centre de Recherche du CHU de Québec, Université Laval, Department of Infectious Diseases and Immunity, Québec City, QC, Canada; Canadian National Transplantation Research Program, Edmonton, AB, Canada.
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8
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Duffney PF, Falsetta ML, Rackow AR, Thatcher TH, Phipps RP, Sime PJ. Key roles for lipid mediators in the adaptive immune response. J Clin Invest 2018; 128:2724-2731. [PMID: 30108196 DOI: 10.1172/jci97951] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Chronic inflammation is an underlying feature of many diseases, including chronic obstructive pulmonary disease, rheumatoid arthritis, asthma, and multiple sclerosis. There is an increasing appreciation of the dysregulation of adaptive immunity in chronic inflammatory and allergic diseases. The discovery of specialized pro-resolving lipid mediators (SPMs) that actively promote the resolution of inflammation has opened new avenues for the treatment of chronic inflammatory diseases. Much work has been done focusing on the impact of SPMs on innate immune cells. However, much less is known about the influence of SPMs on the development of antigen-specific adaptive immune responses. This Review highlights the important breakthroughs concerning the effects of SPMs on the key cell types involved in the development of adaptive immunity, namely dendritic cells, T cells, and B cells.
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Affiliation(s)
- Parker F Duffney
- Department of Environmental Medicine.,Lung Biology and Disease Program, and
| | - Megan L Falsetta
- Department of Environmental Medicine.,Lung Biology and Disease Program, and
| | - Ashley R Rackow
- Department of Environmental Medicine.,Lung Biology and Disease Program, and
| | - Thomas H Thatcher
- Lung Biology and Disease Program, and.,Division of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Richard P Phipps
- Department of Environmental Medicine.,Lung Biology and Disease Program, and.,Division of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Patricia J Sime
- Department of Environmental Medicine.,Lung Biology and Disease Program, and.,Division of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
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9
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Kuwata H, Yuzurihara C, Kinoshita N, Taki Y, Ikegami Y, Washio S, Hirakawa Y, Yoda E, Aiuchi T, Itabe H, Nakatani Y, Hara S. The group VIA calcium‐independent phospholipase A
2
and NFATc4 pathway mediates IL‐1β‐induced expression of chemokines CCL2 and CXCL10 in rat fibroblasts. FEBS J 2018; 285:2056-2070. [DOI: 10.1111/febs.14462] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 03/15/2018] [Accepted: 04/03/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Hiroshi Kuwata
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
| | - Chihiro Yuzurihara
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
| | - Natsumi Kinoshita
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
| | - Yuki Taki
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
| | - Yuki Ikegami
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
| | - Sana Washio
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
| | - Yushi Hirakawa
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
| | - Emiko Yoda
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
| | - Toshihiro Aiuchi
- Division of Biological Chemistry Department of Molecular Biology School of Pharmacy Showa University Tokyo Japan
| | - Hiroyuki Itabe
- Division of Biological Chemistry Department of Molecular Biology School of Pharmacy Showa University Tokyo Japan
| | - Yoshihito Nakatani
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
| | - Shuntaro Hara
- Division of Health Chemistry Department of Healthcare and Regulatory Sciences School of Pharmacy Showa University Tokyo Japan
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10
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Lin Y, Bogdanov M, Lu S, Guan Z, Margolin W, Weiss J, Zheng L. The phospholipid-repair system LplT/Aas in Gram-negative bacteria protects the bacterial membrane envelope from host phospholipase A 2 attack. J Biol Chem 2018; 293:3386-3398. [PMID: 29348168 PMCID: PMC5836115 DOI: 10.1074/jbc.ra117.001231] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 01/15/2018] [Indexed: 11/06/2022] Open
Abstract
Secretory phospholipases A2 (sPLA2s) are potent components of mammalian innate-immunity antibacterial mechanisms. sPLA2 enzymes attack bacteria by hydrolyzing bacterial membrane phospholipids, causing membrane disorganization and cell lysis. However, most Gram-negative bacteria are naturally resistant to sPLA2 Here we report a novel resistance mechanism to mammalian sPLA2 in Escherichia coli, mediated by a phospholipid repair system consisting of the lysophospholipid transporter LplT and the acyltransferase Aas in the cytoplasmic membrane. Mutation of the lplT or aas gene abolished bacterial lysophospholipid acylation activity and drastically increased bacterial susceptibility to the combined actions of inflammatory fluid components and sPLA2, resulting in bulk phospholipid degradation and loss of colony-forming ability. sPLA2-mediated hydrolysis of the three major bacterial phospholipids exhibited distinctive kinetics and deacylation of cardiolipin to its monoacyl-derivative closely paralleled bacterial death. Characterization of the membrane envelope in lplT- or aas-knockout mutant bacteria revealed reduced membrane packing and disruption of lipid asymmetry with more phosphatidylethanolamine present in the outer leaflet of the outer membrane. Moreover, modest accumulation of lysophospholipids in these mutant bacteria destabilized the inner membrane and rendered outer membrane-depleted spheroplasts much more sensitive to sPLA2 These findings indicated that LplT/Aas inactivation perturbs both the outer and inner membranes by bypassing bacterial membrane maintenance mechanisms to trigger specific interfacial activation of sPLA2 We conclude that the LplT/Aas system is important for maintaining the integrity of the membrane envelope in Gram-negative bacteria. Our insights may help inform new therapeutic strategies to enhance host sPLA2 antimicrobial activity.
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Affiliation(s)
- Yibin Lin
- From the Center for Membrane Biology, Department of Biochemistry and Molecular Biology and
| | | | - Shuo Lu
- From the Center for Membrane Biology, Department of Biochemistry and Molecular Biology and
| | - Ziqiang Guan
- the Department of Biochemistry, Duke University School of Medicine, Durham, North Carolina 27710, and
| | - William Margolin
- Microbiology and Molecular Genetics, University of Texas McGovern Medical School, Houston, Texas 77030
| | - Jerrold Weiss
- the Inflammation Program and Departments of Internal Medicine and Microbiology, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242
| | - Lei Zheng
- From the Center for Membrane Biology, Department of Biochemistry and Molecular Biology and
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11
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Kordon AO, Abdelhamed H, Ahmed H, Park JY, Karsi A, Pinchuk LM. Phagocytic and Bactericidal Properties of Channel Catfish Peritoneal Macrophages Exposed to Edwardsiella ictaluri Live Attenuated Vaccine and Wild-Type Strains. Front Microbiol 2018; 8:2638. [PMID: 29375507 PMCID: PMC5767262 DOI: 10.3389/fmicb.2017.02638] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 12/18/2017] [Indexed: 12/13/2022] Open
Abstract
Edwardsiella ictaluri (E. ictaluri), a Gram-negative, intracellular, facultative bacterium, is the causative agent of enteric septicemia of catfish (ESC), which is one of the most significant diseases of farmed channel catfish. Macrophages have a critical role in major defense mechanisms against bacterial infections by migrating to the site of infection, engulfing and killing pathogens, and priming adaptive immune responses. Vaccination of catfish with E. ictaluri live attenuated vaccine (LAV) strains increased the efficiency of phagocytosis and bacterial killing in catfish peritoneal macrophages compared in vitro with macrophages from non-vaccinated fish. Recently, our group developed several protective LAV strains from E. ictaluri. However, their effects on the antigen uptake and bacterial killing in catfish macrophages have not been evaluated. In this study, we assessed the phagocytic and bactericidal activity of peritoneal macrophages in the uptake of E. ictaluri wild-type (WT) and two LAV strains. We found that phagocytosis of LAV strains was significantly higher compared to their WT counterpart in peritoneal macrophages. Moreover, the uptake of E. ictaluri opsonized with sera from vaccinated catfish was more efficient than when opsonized with sera from sham-vaccinated fish. Notably, catfish macrophages did not lose their phagocytic properties at 4°C, as described previously in mammalian and zebrafish models. Also, opsonization of E. ictaluri with inactivated sera from vaccinated and sham-vaccinated catfish decreased significantly phagocytic uptake of bacteria at 32°C, and virtually suppressed endocytosis at 4°C, suggesting the important role of complement-dependent mechanisms in catfish macrophage phagocytosis. In conclusion, our data on enhanced phagocytic capacity and effective killing ability in macrophages of vaccine strains suggested the LAVs’ advantage if processed and presented in the form of peptides to specific lymphocytes of an adaptive immune system and emphasize the importance of macrophage-mediated immunity against ESC. Furthermore, we showed the role of complement-dependent mechanisms in the phagocytic uptakes of E. ictaluri in catfish peritoneal macrophages at 4 and 32°C. Finally, LAV vaccine-induced bacterial phagocytosis and killing properties of peritoneal macrophages emphasized the importance of the innate immune responses in ESC.
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Affiliation(s)
- Adef O Kordon
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States
| | - Hossam Abdelhamed
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States
| | - Hamada Ahmed
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States.,Department of Nutrition and Veterinary Clinical Nutrition, Faculty of Veterinary Medicine, Damanhour University, Damanhour, Egypt
| | - Joo Y Park
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States
| | - Attila Karsi
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States
| | - Lesya M Pinchuk
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States
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12
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Masuda N, Mantani Y, Yoshitomi C, Yuasa H, Nishida M, Arai M, Kawano J, Yokoyama T, Hoshi N, Kitagawa H. Immunohistochemical study on the secretory host defense system with lysozyme and secretory phospholipase A2 throughout rat respiratory tract. J Vet Med Sci 2017; 80:323-332. [PMID: 29225322 PMCID: PMC5836772 DOI: 10.1292/jvms.17-0503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The host defense system with lysozyme and secretory phospholipase A2 (sPLA2) was immunohistochemically investigated in rat respiratory tract under healthy conditions. In the nasal epithelium, a large number of non-ciliated and non-microvillous cells (NC) and a small number of goblet cells (GC) were immunopositive for lysozyme and sPLA2. A few acinar cells and almost all epithelial cells of intercalated ducts were immunopositive for both bactericidal substances in the nasal glands. In the laryngeal and tracheal epithelia, few NC and GC were immunopositive for both bactericidal substances. In the laryngeal and tracheal glands, a few acinar cells and most ductal epithelial cells were immunopositive for both bactericidal substances. In extra-pulmonary bronchus, small numbers of NC and GC were immunopositive for lysozyme and sPLA2, whereas few NC and no GC were immunopositive in the intra-pulmonary bronchus. No secretory source of either bactericidal substance was located in the bronchioles. In the alveolus, many glandular epithelial cells and alveolar macrophages were immunopositive for lysozyme but immunonegative for sPLA2. Moreover, lysozyme and sPLA2 were detected in the mucus layer and in the periciliary layer from the nose to the extra-pulmonary bronchus. These findings suggest that secretory sources of lysozyme and sPLA2 are distributed in almost all the respiratory tract. Their secretory products are probably transported to the pharynx and contribute to form the first line of defense against inhaled bacteria throughout the respiratory tract.
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Affiliation(s)
- Natsumi Masuda
- Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Youhei Mantani
- Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Chiaki Yoshitomi
- Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Hideto Yuasa
- Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Miho Nishida
- Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Masaya Arai
- Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Junichi Kawano
- Laboratory of Microbiology and Immunology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Toshifumi Yokoyama
- Laboratory of Molecular Morphology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Nobuhiko Hoshi
- Laboratory of Molecular Morphology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Hiroshi Kitagawa
- Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
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13
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Marth CD, Firestone SM, Glenton LY, Browning GF, Young ND, Krekeler N. Oestrous cycle-dependent equine uterine immune response to induced infectious endometritis. Vet Res 2016; 47:110. [PMID: 27825391 PMCID: PMC5101692 DOI: 10.1186/s13567-016-0398-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 07/26/2016] [Indexed: 12/18/2022] Open
Abstract
Infectious endometritis is a major cause of reduced pregnancy rates in horses. The objectives of this study were to establish a timeline of the innate immune response in the uterus of healthy horses and to investigate the oestrous cycle effect on this. Endometrial biopsies were collected from five horses before and at 3, 12, 24, 48 and 72 h after inoculation of Escherichia coli, once in oestrus and once in dioestrus. They were analysed by quantitative real-time PCR, microbiology and histology. Neutrophil numbers increased from very low levels in the absence of inflammation to severe neutrophilia 3 h after inoculation. The concentrations of mRNAs for Toll-like receptor (TLR)2, TLR4, NOD-like receptor NLRC5, tissue inhibitor of metallopeptidases 1 (TIMP1) and chemokines CCL2, CXCL9, CXCL10 and CXCL11 were all increased 3 h after inoculation of E. coli compared to levels detected prior to inoculation. Chemokine mRNA levels remained elevated for 48 h. Concentrations of mRNAs for the antimicrobial peptides equine β-defensin 1 (EBD1), lysozyme, secretory leukoprotease inhibitor (SLPI), lipocalin 2 (LCN2), lactoferrin and uteroferrin were increased between 3 and 12 h post inoculation. The gene for secreted phospholipase A2 (sPLA2) was expressed constitutively. P19 uterocalin mRNA levels were higher in dioestrus than in oestrus over the first 24 h of inflammation. Neutrophils and many innate immune genes responded rapidly to the introduction of E. coli into the uterus, while the oestrous cycle stage had only a relatively minor effect on the response to E. coli. This study has delineated a useful model of innate immunity in infectious endometritis of healthy animals.
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Affiliation(s)
- Christina D Marth
- Asia-Pacific Centre for Animal Health, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia. .,Translational Research and Animal Clinical Trial Study Group, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, VIC, Australia.
| | - Simon M Firestone
- Asia-Pacific Centre for Animal Health, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Lisa Y Glenton
- Asia-Pacific Centre for Animal Health, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia.,Translational Research and Animal Clinical Trial Study Group, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, VIC, Australia
| | - Glenn F Browning
- Asia-Pacific Centre for Animal Health, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Neil D Young
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Natali Krekeler
- Asia-Pacific Centre for Animal Health, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia.,Translational Research and Animal Clinical Trial Study Group, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, VIC, Australia
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14
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Flannagan RS, Heit B, Heinrichs DE. Antimicrobial Mechanisms of Macrophages and the Immune Evasion Strategies of Staphylococcus aureus. Pathogens 2015; 4:826-68. [PMID: 26633519 PMCID: PMC4693167 DOI: 10.3390/pathogens4040826] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 11/17/2015] [Accepted: 11/24/2015] [Indexed: 12/21/2022] Open
Abstract
Habitually professional phagocytes, including macrophages, eradicate microbial invaders from the human body without overt signs of infection. Despite this, there exist select bacteria that are professional pathogens, causing significant morbidity and mortality across the globe and Staphylococcus aureus is no exception. S. aureus is a highly successful pathogen that can infect virtually every tissue that comprises the human body causing a broad spectrum of diseases. The profound pathogenic capacity of S. aureus can be attributed, in part, to its ability to elaborate a profusion of bacterial effectors that circumvent host immunity. Macrophages are important professional phagocytes that contribute to both the innate and adaptive immune response, however from in vitro and in vivo studies, it is evident that they fail to eradicate S. aureus. This review provides an overview of the antimicrobial mechanisms employed by macrophages to combat bacteria and describes the immune evasion strategies and some representative effectors that enable S. aureus to evade macrophage-mediated killing.
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Affiliation(s)
- Ronald S Flannagan
- Department of Microbiology and Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
| | - Bryan Heit
- Department of Microbiology and Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
- Centre for Human Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
| | - David E Heinrichs
- Department of Microbiology and Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
- Centre for Human Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
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15
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Abstract
PURPOSE OF REVIEW Methicillin-resistant strains of the important human pathogen Staphylococcus aureus pose a significant public health threat in the community, as they are easily transmitted, especially prone to cause invasive disease, and infect otherwise healthy individuals. The mechanistic basis for the ability of these organisms to evade the innate immune responses remains incompletely defined. RECENT FINDINGS The success of pathogens such as S. aureus rests, in part, on their capacity to overcome neutrophil-mediated host defense to establish infection and cause human disease. S. aureus has the potential to thwart effective neutrophil chemotaxis, and phagocytosis, and succeeds in evading killing by neutrophils. Furthermore, S. aureus surviving within neutrophils promotes neutrophil cytolysis, with release of host-derived molecules that promote local inflammation. Here, we provide a brief overview of our understanding of the mechanisms by which S. aureus - including methicillin-resistant S. aureus - avoids neutrophil-mediated host defense and causes disease. SUMMARY Understanding the molecular mechanisms by which S. aureus avoids neutrophil-mediated responses and initiates signaling cascades that culminate in neutrophil lysis will provide insights prerequisite to the development of novel targets for treating staphylococcal infections.
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Weiss JP. Molecular determinants of bacterial sensitivity and resistance to mammalian Group IIA phospholipase A2. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:3072-7. [PMID: 26079797 DOI: 10.1016/j.bbamem.2015.05.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 05/18/2015] [Accepted: 05/20/2015] [Indexed: 11/25/2022]
Abstract
Group IIA secretory phospholipase A2 (sPLA(2)-IIA) of mammalian species is unique among the many structurally and functionally related mammalian sPLA(2) in their high net positive charge and potent (nM) antibacterial activity. Toward the Gram-positive bacteria tested thus far, the global cationic properties of sPLA(2)-IIA are necessary for optimal binding to intact bacteria and penetration of the multi-layered thick cell wall, but not for the degradation of membrane phospholipids that is essential for bacterial killing. Various Gram-positive bacterial species can differ as much as 1000-fold in sPLA(2)-IIA sensitivity despite similar intrinsic enzymatic activity of sPLA(2)-IIA toward the membrane phospholipids of various bacteria. d-alanylation of wall- and lipo-teichoic acids in Staphylococcus aureus and sortase function in Streptococcus pyogenes increase bacterial resistance to sPLA(2)-IIA by up to 100-fold apparently by affecting translocation of bound sPLA(2)-IIA to the cell membrane. Action of the sPLA(2)-IIA and other related sPLA(2) against Gram-negative bacteria is more dependent on cationic properties of the enzyme near the amino-terminus of the protein and collaboration with other host defense proteins that produce alterations of the unique Gram-negative bacterial outer membrane that normally represents a barrier to sPLA(2)-IIA action. This article is part of a Special Issue entitled: Bacterial Resistance to Antimicrobial Peptides.
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Affiliation(s)
- Jerrold P Weiss
- The Inflammation Program, University of Iowa, Iowa City, IA 52242, USA; Department of Internal Medicine, University of Iowa, Iowa City, IA 52242, USA; Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA; Veterans Administration Medical Center, Iowa City, IA 52246, USA.
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17
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Yang X, Sheng W, Ridgley DM, Haidekker MA, Sun GY, Lee JC. Astrocytes regulate α-secretase-cleaved soluble amyloid precursor protein secretion in neuronal cells: Involvement of group IIA secretory phospholipase A2. Neuroscience 2015; 300:508-17. [PMID: 26037803 DOI: 10.1016/j.neuroscience.2015.05.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 12/19/2022]
Abstract
Astrocytes are major supportive cells in brains with important functions including providing nutrients and regulating neuronal activities. In this study, we demonstrated that astrocytes regulate amyloid precursor protein (APP) processing in neuronal cells through secretion of group IIA secretory phospholipase A2 (sPLA2-IIA). When astrocytic cells (DITNC) were mildly stimulated with the pro-inflammatory cytokines, such as TNF α and IL-1β, sPLA2-IIA was secreted into the medium. When conditioned medium containing sPLA2-IIA was applied to human neuroblastoma (SH-SY5Y) cells, there was an increase in both cell membrane fluidity and secretion of α-secretase-cleaved soluble amyloid precursor protein (sAPPα). These changes were abrogated by KH064, a selective inhibitor of sPLA2-IIA. In addition, exposing SH-SY5Y cells to recombinant human sPLA2-IIA also increased membrane fluidity, accumulation of APP at the cell surface, and secretion of sAPPα, but without altering total expressions of APP, α-secretases and β-site APP cleaving enzyme (BACE1). Taken together, our results provide novel information regarding a functional role of sPLA2-IIA in astrocytes for regulating APP processing in neuronal cells.
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Affiliation(s)
- X Yang
- Hope Center for Neurological Disorders and Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, United States
| | - W Sheng
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, United States
| | - D M Ridgley
- Department of Bioengineering, University of Missouri, Columbia, MO 65211, United States
| | - M A Haidekker
- College of Engineering, Driftmier Engineering Center, University of Georgia, Athens, GA 30602, United States
| | - G Y Sun
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, United States
| | - J C Lee
- Department of Bioengineering, University of Missouri, Columbia, MO 65211, United States; Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, United States.
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18
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Mantani Y, Ito E, Nishida M, Yuasa H, Masuda N, Qi WM, Kawano J, Yokoyama T, Hoshi N, Kitagawa H. Ultrastructural study on the morphological changes in indigenous bacteria of mucous layer and chyme throughout the rat intestine. J Vet Med Sci 2015; 77:1121-8. [PMID: 25890991 PMCID: PMC4591154 DOI: 10.1292/jvms.15-0139] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Indigenous bacteria in the alimentary tract are exposed to various bactericidal
peptides and digestive enzymes, but the viability status and morphological changes of
indigenous bacteria are unclear. Therefore, the present study aimed to ultrastructurally
clarify the degeneration and viability status of indigenous bacteria in the rat intestine.
The majority of indigenous bacteria in the ileal mucous layer possessed intact cytoplasm,
but the cytoplasm of a few bacteria contained vacuoles. The vacuoles were more frequently
found in bacteria of ileal chyme than in those of ileal mucous layer and were found in a
large majority of bacteria in both the mucous layer and chyme throughout the large
intestine. In the dividing bacteria of the mucous layer and chyme throughout the
intestine, the ratio of area occupied by vacuoles was almost always less than 10%. Lysis
or detachment of the cell wall in the indigenous bacteria was more frequently found in the
large intestine than in the ileum, whereas bacterial remnants, such as cell walls, were
distributed almost evenly throughout the intestine. In an experimental control of
long-time-cultured Staphylococcus epidermidis on agar, similar vacuoles
were also found, but cell-wall degeneration was never observed. From these findings,
indigenous bacteria in the mucous layer were ultrastructurally confirmed to be the source
of indigenous bacteria in the chyme. Furthermore, the results suggested that indigenous
bacteria were more severely degenerated toward the large intestine and were probably
degraded in the intestine.
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Affiliation(s)
- Youhei Mantani
- Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
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The enteric nervous system neuropeptide, bombesin, reverses innate immune impairments during parenteral nutrition. Ann Surg 2015; 260:432-43; discussion 443-4. [PMID: 25115419 DOI: 10.1097/sla.0000000000000871] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Lack of enteral stimulation during parenteral nutrition (PN) impairs mucosal immunity. Bombesin (BBS), a gastrin-releasing peptide analogue, reverses PN-induced defects in acquired immunity. Paneth cells produce antimicrobial peptides (AMPs) of innate immunity for release after cholinergic stimulation. OBJECTIVE Determine if BBS restores AMPs and bactericidal function during PN. METHODS Intravenously cannulated male ICR mice were randomized to Chow, PN, or PN+BBS (15 μg 3 times daily, n = 7 per group) for 5 days. Ileum was analyzed for AMPs (Protein: sPLA2 by fluorescence, lysozyme and RegIII-γ by western andcryptdin-4 by ELISA; mRNA: all by RT-PCR). Cholinergic stimulated (100 μM bethanechol) ileal specimens assessed Pseudomonas bactericidal activity. Ileum (Chow: n = 7; PN: n = 9; PN+BBS: n = 8) was assessed for Escherichia coli invasion in ex-vivo culture. RESULTS PN significantly decreased most AMPs versus Chow while BBS maintained Chow levels (sPLA2: Chow: 107 + 14*, PN: 44.6 + 7.2, PN+BBS: 78.7 + 13.4* Fl/min/μL/total protein; Lysozyme: Chow: 63.9 + 11.9*, PN: 26.8 + 6.2; PN+BBS: 64.9 + 13.8* lysozyme/total protein; RegIII-γ: Chow: 51.5 + 10.0*, PN: 20.4 + 4.3, PN+BBS: 31.0 + 8.4 RegIII-γ/total protein; Cryptdin-4: Chow: 18.4 + 1.5*, PN: 12.7 + 1.6, PN+BBS: 26.1 + 2.4*† pg/mg [all *P < 0.05 vs PN and †P < 0.05 vs Chow]). Functionally, BBS prevented PN loss of bactericidal activity after cholinergic stimulation (Chow: 25.3 + 3.6*, PN: 13.0 + 3.2; PN+BBS: 27.0 + 4.7* percent bacterial killing, *P < 0.05 vs PN). BBS reduced bacterial invasion in unstimulated tissue barely missing significance (P = 0.06). CONCLUSIONS The enteric nervous system (ENS) controls AMP levels in Paneth cells during PN but mucosal protection by innate immunity requires both ENS and parasympathetic stimulation.
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Abstract
BACKGROUND Parenteral nutrition (PN) increases risks of infections in critically injured patients. Recently, PN was shown to reduce intestine luminal levels of the Paneth cell antimicrobial molecule secretory phospholipase A2 (sPLA2) and the goblet cell glycoprotein mucin2 (MUC2). These molecules are critical factors for innate mucosal immunity and provide barrier protection. Interleukin-4 (IL-4) and IL-13 regulate sPLA2 and MUC2 production through the IL-13 receptor. Because IL-25 stimulates IL-4 and IL-13 release and PN reduces luminal sPLA2 and MUC2, we hypothesized that adding IL-25 to PN would restore these innate immune factors and maintain barrier function. METHODS Two days after venous cannulation, male ICR (Institute of Cancer Research) mice were randomized to receive chow (n = 12), PN (n = 9), or PN + 0.7 μg of exogenous IL-25 (n = 11) daily for 5 days. Small-intestine wash fluid (SIWF) was collected for analysis of sPLA2 activity, MUC2 density, and luminal levels of IL-4 and IL-13. Small-intestinal tissue was harvested for analysis of tissue sPLA2 activity or immediate use in an ex-vivo intestinal segment culture (EVISC) to assess susceptibility of the tissue segments to enteroinvasive Escherichia coli. RESULTS PN reduced luminal sPLA2 (P < 0.0001) and MUC2 (P <0.002) compared with chow, whereas the addition of IL-25 to PN increased luminal sPLA2 (P < 0.0001) and MUC2 (P < 0.02) compared with PN. Tissue IL-4 and IL-13 decreased with PN compared with chow (IL-4: P < 0.0001, IL-13: P < 0.002), whereas IL-25 increased both cytokines compared with PN (IL-4: P < 0.03, IL-13: P < 0.02). Tissue levels of sPLA2 were significantly decreased with PN compared with chow, whereas IL-25 significantly increased tissue sPLA2 levels compared with PN alone. Functionally, more bacteria invaded the PN-treated tissue compared with chow (P < 0.01), and the addition of IL-25 to PN decreased enteroinvasion to chow levels (P < 0.01). CONCLUSIONS PN impairs innate mucosal immunity by suppressing luminal sPLA2 activity and MUC2 density compared with chow. PN also increases bacterial invasion in ex-vivo tissue. Administration of exogenous IL-25 reverses this dysfunction and increases luminal sPLA2 and MUC2. PN tissue treated with IL-25 was significantly more resistant to bacterial invasion than with PN alone, suggesting that IL-25-induced effects augment the barrier defense mechanisms.
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Romero R, Yoon BH, Chaemsaithong P, Cortez J, Park CW, Gonzalez R, Behnke E, Hassan SS, Gotsch F, Yeo L, Chaiworapongsa T. Secreted phospholipase A2 is increased in meconium-stained amniotic fluid of term gestations: potential implications for the genesis of meconium aspiration syndrome. J Matern Fetal Neonatal Med 2014; 27:975-83. [PMID: 24063538 DOI: 10.3109/14767058.2013.847918] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Meconium-stained amniotic fluid (MSAF) represents the passage of fetal colonic content into the amniotic cavity. Meconium aspiration syndrome (MAS) is a complication that occurs in a subset of infants with MSAF. Secreted phospholipase A2 (sPLA2) is detected in meconium and is implicated in the development of MAS. The purpose of this study was to determine if sPLA2 concentrations are increased in the amniotic fluid of women in spontaneous labor at term with MSAF. MATERIALS AND METHODS This was a cross-sectional study of patients in spontaneous term labor who underwent amniocentesis (n = 101). The patients were divided into two study groups: (1) MSAF (n = 61) and (2) clear fluid (n = 40). The presence of bacteria and endotoxin as well as interleukin-6 (IL-6) and sPLA2 concentrations in the amniotic fluid were determined. Statistical analyses were performed to test for normality and bivariate analysis. The Spearman correlation coefficient was used to study the relationship between sPLA2 and IL-6 concentrations in the amniotic fluid. RESULTS Patients with MSAF have a higher median sPLA2 concentration (ng/mL) in amniotic fluid than those with clear fluid [1.7 (0.98-2.89) versus 0.3 (0-0.6), p < 0.001]. Among patients with MSAF, those with either microbial invasion of the amniotic cavity (MIAC, defined as presence of bacteria in the amniotic cavity), or bacterial endotoxin had a significantly higher median sPLA2 concentration (ng/mL) in amniotic fluid than those without MIAC or endotoxin [2.4 (1.7-6.0) versus 1.7 (1.3-2.5), p < 0.05]. There was a positive correlation between sPLA2 and IL-6 concentrations in the amniotic fluid (Spearman Rho = 0.3, p < 0.05). CONCLUSION MSAF that contains bacteria or endotoxin has a higher concentration of sPLA2, and this may contribute to induce lung inflammation when meconium is aspirated before birth.
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Affiliation(s)
- Roberto Romero
- Perinatology Research Branch, NICHD/NIH/DHHS , Bethesda, MD and Detroit, MI , USA
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Antibacterial properties of recombinant human non-pancreatic secretory phospholipase A2. Biochem Biophys Res Commun 2013; 441:453-6. [DOI: 10.1016/j.bbrc.2013.10.092] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Accepted: 10/17/2013] [Indexed: 11/23/2022]
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Movert E, Wu Y, Lambeau G, Kahn F, Touqui L, Areschoug T. Secreted Group IIA Phospholipase A2 Protects Humans Against the Group B Streptococcus: Experimental and Clinical Evidence. J Infect Dis 2013; 208:2025-35. [DOI: 10.1093/infdis/jit359] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Neonatal host defense against Staphylococcal infections. Clin Dev Immunol 2013; 2013:826303. [PMID: 23935651 PMCID: PMC3722842 DOI: 10.1155/2013/826303] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 05/14/2013] [Accepted: 05/14/2013] [Indexed: 12/17/2022]
Abstract
Preterm infants are especially susceptible to late-onset sepsis that is often due to Gram-positive bacterial infections resulting in substantial morbidity and mortality. Herein, we will describe neonatal innate immunity to Staphylococcus spp. comparing differences between preterm and full-term newborns with adults. Newborn innate immunity is distinct demonstrating diminished skin integrity, impaired Th1-polarizing responses, low complement levels, and diminished expression of plasma antimicrobial proteins and peptides, especially in preterm newborns. Characterization of distinct aspects of the neonatal immune response is defining novel approaches to enhance host defense to prevent and/or treat staphylococcal infection in this vulnerable population.
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Miki Y, Yamamoto K, Taketomi Y, Sato H, Shimo K, Kobayashi T, Ishikawa Y, Ishii T, Nakanishi H, Ikeda K, Taguchi R, Kabashima K, Arita M, Arai H, Lambeau G, Bollinger JM, Hara S, Gelb MH, Murakami M. Lymphoid tissue phospholipase A2 group IID resolves contact hypersensitivity by driving antiinflammatory lipid mediators. ACTA ACUST UNITED AC 2013; 210:1217-34. [PMID: 23690440 PMCID: PMC3674707 DOI: 10.1084/jem.20121887] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PLA2G2D ameliorates skin inflammation through mobilizing pro-resolving lipid mediators. Resolution of inflammation is an active process that is mediated in part by antiinflammatory lipid mediators. Although phospholipase A2 (PLA2) enzymes have been implicated in the promotion of inflammation through mobilizing lipid mediators, the molecular entity of PLA2 subtypes acting upstream of antiinflammatory lipid mediators remains unknown. Herein, we show that secreted PLA2 group IID (PLA2G2D) is preferentially expressed in CD11c+ dendritic cells (DCs) and macrophages and displays a pro-resolving function. In hapten-induced contact dermatitis, resolution, not propagation, of inflammation was compromised in skin and LNs of PLA2G2D-deficient mice (Pla2g2d−/−), in which the immune balance was shifted toward a proinflammatory state over an antiinflammatory state. Bone marrow-derived DCs from Pla2g2d−/− mice were hyperactivated and elicited skin inflammation after intravenous transfer into mice. Lipidomics analysis revealed that PLA2G2D in the LNs contributed to mobilization of a pool of polyunsaturated fatty acids that could serve as precursors for antiinflammatory/pro-resolving lipid mediators such as resolvin D1 and 15-deoxy-Δ12,14-prostaglandin J2, which reduced Th1 cytokine production and surface MHC class II expression in LN cells or DCs. Altogether, our results highlight PLA2G2D as a “resolving sPLA2” that ameliorates inflammation through mobilizing pro-resolving lipid mediators and points to a potential use of this enzyme for treatment of inflammatory disorders.
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Affiliation(s)
- Yoshimi Miki
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
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Parenteral nutrition increases susceptibility of ileum to invasion by E coli. J Surg Res 2013; 183:583-91. [PMID: 23481564 DOI: 10.1016/j.jss.2013.01.054] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 01/16/2013] [Accepted: 01/25/2013] [Indexed: 02/05/2023]
Abstract
BACKGROUND Parenteral nutrition (PN), with the lack of enteral feeding, compromises mucosal immune function and increases the risk of infections. We developed an ex vivo intestinal segment culture (EVISC) model to study the ex vivo effects of PN on susceptibility of the ileum to invasion by extra-intestinal pathogenic Escherichia coli (ExPEC) and on ileal secretion of antimicrobial secretory phospholipase A2 (sPLA2) in response to the pathogen. MATERIALS AND METHODS Study 1: Using mouse (n = 7) ileal tissue, we examined the effects of ileal region (proximal versus distal) and varying ExPEC inoculum concentrations on ex vivo susceptibility to ExPEC invasion and sPLA2 secretion. Study 2: Ten mice were randomized to oral chow or intravenous PN feeding for 5 d (n = 5/group). Using the EVISC model, we compared the susceptibility of ileal tissue to invasion by ExPEC and sPLA2 secretion in response to the pathogen. RESULTS Study 1: The proximal ileum was more susceptible to invasion (P < 0.0001) and secreted lower amounts of sPLA2 (P = 0.0002) than the distal ileum. Study 2: Ileal tissue from PN-fed animals was more susceptible (approximately 4-fold, P = 0.018) to invasion than those from chow-fed animals. Ileal tissue from PN-fed animals secreted less sPLA2 (P < 0.02) than those from chow-fed animals. CONCLUSIONS The data illustrate EVISC as a reproducible model for studying host-pathogen interactions and the effects of diet on susceptibility to infections. Specifically, the findings support our hypothesis that PN with the lack of enteral feeding decreases mucosal responsiveness to pathogen exposure and provides a plausible mechanism by which PN is associated with increased risk of infectious complication.
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Ben Bacha A, Abid I, Horchani H. Antibacterial properties of intestinal phospholipase A2 from the common stingray Dasyatis pastinaca. Appl Biochem Biotechnol 2012; 168:1277-87. [PMID: 22956299 DOI: 10.1007/s12010-012-9856-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Accepted: 08/21/2012] [Indexed: 11/29/2022]
Abstract
Stingray phospholipase A(2) group IIA (SPLA(2)-IIA) was recently isolated and purified to homogeneity from the intestine of the common stingray Dasyatis pastinaca, suggesting that this enzyme plays an important role in systemic bactericidal defense. The present study showed that SPLA(2)-IIA was highly bactericidal against Gram-positive bacteria with inhibition zones and minimal inhibitory concentration values in the range of 13-25 mm and 2-8 μg/ml, respectively, whereas Gram-negative bacteria exhibited a much higher resistance. The bactericidal efficiency of SPLA(2)-IIA was shown to be unaffected by high protein and salt concentrations, but dependent upon the presence of calcium ions, and then correlated to the hydrolytic activity of membrane phospholipids. Importantly, we showed that stingray phospholipase A(2) group IIA presents no cytotoxicity after its incubation with MDA-MB-231 cells. SPLA(2)-IIA may be considered as a future therapeutic agent against bacterial infections.
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Affiliation(s)
- Abir Ben Bacha
- Biochemistry Department, Science College, King Saud University, Riyadh, Saudi Arabia.
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Understanding the lipid-digestion processes in the GI tract before designing lipid-based drug-delivery systems. Ther Deliv 2012; 3:105-24. [PMID: 22833936 DOI: 10.4155/tde.11.138] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Many of the compounds present in lipid-based drug-delivery systems are esters, such as acylglycerols, phospholipids, polyethyleneglycol mono- and di-esters and polysorbate, which can be hydrolyzed by the various lipolytic enzymes present in the GI tract. Lipolysis of these compounds, along with dietary fats, affects the solubility, dispersion and bioavailibity of poorly water-soluble drugs. Pharmaceutical scientists have been taking a new interest in fat digestion in this context, and several studies presenting in vitro gastrointestinal lipolysis models have been published. In most models, it is generally assumed that pancreatic lipase is the main enzyme involved in the gastrointestinal lipolysis of lipid formulations. It was established, however, that gastric lipase, pancreatic carboxyl ester hydrolaze and pancreatic lipase-related protein 2 are the major players involved in the lipolysis of lipid excipients containing acylglycerols and polyethyleneglycol esters. These findings have shown that the lipolysis of lipid excipients may actually start in the stomach and involve several lipolytic enzymes. These findings should therefore be taken into account when testing in vitro the dispersion and bioavailability of poorly water-soluble drugs formulated with lipids. In this review, we present the latest data available about the lipolytic enzymes involved in gastrointestinal lipolysis and suggest tracks for designing physiologically relevant in vitro digestion models.
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Zhou L, Beuerman RW. Tear analysis in ocular surface diseases. Prog Retin Eye Res 2012; 31:527-50. [PMID: 22732126 DOI: 10.1016/j.preteyeres.2012.06.002] [Citation(s) in RCA: 185] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 06/06/2012] [Accepted: 06/08/2012] [Indexed: 01/20/2023]
Abstract
The thin layer of tears covering the ocular surface are a complex body fluid containing thousands of molecules of varied form and function of several origins. In this review, we have discussed some key issues in the analysis of tears in the context of understanding and diagnosing eye disease using current technologies of proteomics and metabolomics, and for their potential for clinical application. In the last several years, advances in proteomics/metabolomics/lipidomics technologies have greatly expanded our knowledge of the chemical composition of tear fluid. The quickened pace of studies has shown that tears as a complex extra-cellular fluid of the ocular surface contains a great deal of molecular information useful for the diagnosis, prognosis, and treatment of ocular surface diseases that has the ability to addresses the emphasis on personalized medicine and biomarkers of disease. Future research directions will likely include (1) standardize tear collection, storage, extraction, and sample preparation; (2) quantitative proteomic analysis of tear proteins using multiple reaction monitoring (MRM)-based mass spectrometry; (3) population based studies of human tear proteomics/metabolomics; (4) tear proteomics/metabolomics for systemic diseases; and (5) functional studies of tear proteins.
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Affiliation(s)
- Lei Zhou
- Singapore Eye Research Institute, Singapore
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Omata J, Pierre JF, Heneghan AF, Tsao FHC, Sano Y, Jonker MA, Kudsk KA. Parenteral nutrition suppresses the bactericidal response of the small intestine. Surgery 2012; 153:17-24. [PMID: 22698933 DOI: 10.1016/j.surg.2012.04.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 04/12/2012] [Indexed: 11/25/2022]
Abstract
BACKGROUND Parenteral nutrition (PN) increases infectious risk in critically ill patients compared with enteral feeding. Previously, we demonstrated that PN feeding suppresses the concentration of the Paneth cell antimicrobial protein secretory phospholipase A2 (sPLA2) in the gut lumen. sPLA2 and other Paneth cell proteins are released in response to bacterial components, such as lipopolysaccharide (LPS), and they modulate the intestinal microbiome. Because the Paneth cell protein sPLA2 was suppressed with PN feeding, we hypothesized PN would diminish the responsiveness of the small bowel to LPS through reduced secretions and as a result exhibit less bactericidal activity. METHODS The distal ileum was harvested from Institute of Cancer Research mice, washed, and randomized for incubation with LPS (0, 1, or 10 μg/mL). Culture supernatant was collected and sPLA2 activity was measured. Bactericidal activity of the ileum segment secretions was assessed against Pseudomonas aeruginosa with and without an sPLA2 inhibitor at 2 concentrations, 100 nmol/L and 1 μmol/L. Institute of Cancer Research mice were randomized to chow or PN for 5 days. Tissue was collected for immunohistochemistry (IHC) and ileal segments were incubated with LPS (0 or 10 μg/mL). sPLA2 activity and bactericidal activity were measured in secretions from ileal segments. RESULTS Ileal segments responded to 10 μg/mL LPS with significantly greater sPLA2 activity and bactericidal activity. The bactericidal activity of secretions from LPS stimulated tissue was suppressed 50% and 70%, respectively, with the addition of the sPLA2-inhibitor. Chow displayed greater sPLA2 in the Paneth cell granules and secreted higher levels of sPLA2 than PN before and after LPS. Accordingly, media collected from chow was more bactericidal than PN. IHC confirmed a reduction in Paneth cell granules after PN. CONCLUSION This work demonstrates that ileal segments secrete bactericidal secretions after LPS exposure and the inhibition of the Paneth cell antimicrobial protein sPLA2 significantly diminishes this. PN feeding resulted in suppressed secretion of the sPLA2 and resulted in increased bacterial survival. This demonstrates that PN significantly impairs the innate immune response by suppressing Paneth cell function.
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Affiliation(s)
- Jiro Omata
- Department of Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
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Pierre JF, Heneghan AF, Tsao FHC, Sano Y, Jonker MA, Omata J, Lan J, Kudsk KA. Route and type of nutrition and surgical stress influence secretory phospholipase A2 secretion of the murine small intestine. JPEN J Parenter Enteral Nutr 2012; 35:748-56. [PMID: 22042050 DOI: 10.1177/0148607111414025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The function of secretory phospholipase A2 (sPLA2) is site dependent. In tissue, sPLA2 regulates eicosanoid production; in circulation, sPLA2 primes neutrophils; and in the intestinal lumen, sPLA2 provides innate bactericidal immunity as a defensin-related protein. Since parenteral nutrition (PN) primes leukocytes while suppressing intraluminal mucosal immunity, the authors hypothesized that (1) PN would diminish luminal sPLA2 activity but increase activity in intestinal tissue and serum and (2) stress would accentuate these changes. METHODS Mice received chow, a complex enteral diet (CED), intragastric PN (IG-PN), or PN in experiment 1 and chow, chow+stress, PN, or PN+stress in experiment 2. RESULTS In experiment 1, luminal sPLA2 activity was greatest in chow and decreased in CED, IG-PN, and PN, with PN lower than CED and IG-PN. Compared to that after chow, serum sPLA2 activity dropped after CED, IG-PN, and PN. Serum sPLA2 was higher in portal than systemic serum. In experiment 2, PN lowered luminal sPLA2 activity vs chow. Stress lowered luminal sPLA2 activity in chow, without change in PN. Following stress, luminal immunoglobulin A increased in chow but not PN. Serum sPLA2 activity increased in PN. CONCLUSIONS PN attenuates sPLA2 activity in intestinal fluid, consistent with suppressed innate mucosal defense. Stress suppresses luminal fluid sPLA2 activity in chow but not the immunoglobulin A response; PN impairs both. Stress significantly elevates serum sPLA2 in PN-fed mice, consistent with known increased neutrophil priming with PN. PN reduces innate bactericidal immunity of the gut but upregulates serum proinflammatory products poststress.
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Affiliation(s)
- Joseph F Pierre
- Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
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Movert E, Wu Y, Lambeau G, Touqui L, Areschoug T. A novel bacterial resistance mechanism against human group IIA-secreted phospholipase A2: role of Streptococcus pyogenes sortase A. THE JOURNAL OF IMMUNOLOGY 2011; 187:6437-46. [PMID: 22075700 DOI: 10.4049/jimmunol.1100499] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Human group IIA-secreted phospholipase A(2) (sPLA(2)-IIA) is a bactericidal molecule important for the innate immune defense against Gram-positive bacteria. In this study, we analyzed its role in the host defense against Streptococcus pyogenes, a major human pathogen, and demonstrated that this bacterium has evolved a previously unidentified mechanism to resist killing by sPLA(2)-IIA. Analysis of a set of clinical isolates demonstrated that an ~500-fold higher concentration of sPLA(2)-IIA was required to kill S. pyogenes compared with strains of the group B Streptococcus, which previously were shown to be sensitive to sPLA(2)-IIA, indicating that S. pyogenes exhibits a high degree of resistance to sPLA(2)-IIA. We found that an S. pyogenes mutant lacking sortase A, a transpeptidase responsible for anchoring LPXTG proteins to the cell wall in Gram-positive bacteria, was significantly more sensitive (~30-fold) to sPLA(2)-IIA compared with the parental strain, indicating that one or more LPXTG surface proteins protect S. pyogenes against sPLA(2)-IIA. Importantly, using transgenic mice expressing human sPLA(2)-IIA, we showed that the sortase A-mediated sPLA(2)-IIA resistance mechanism in S. pyogenes also occurs in vivo. Moreover, in this mouse model, we also showed that human sPLA(2)-IIA is important for the defense against lethal S. pyogenes infection. Thus, we demonstrated a novel mechanism by which a pathogenic bacterium can evade the bactericidal action of sPLA(2)-IIA and we showed that sPLA(2)-IIA contributes to the host defense against S. pyogenes infection.
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Affiliation(s)
- Elin Movert
- Division of Medical Microbiology, Department of Laboratory Medicine, Lund University, 22362 Lund, Sweden
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Dennis EA, Cao J, Hsu YH, Magrioti V, Kokotos G. Phospholipase A2 enzymes: physical structure, biological function, disease implication, chemical inhibition, and therapeutic intervention. Chem Rev 2011; 111:6130-85. [PMID: 21910409 PMCID: PMC3196595 DOI: 10.1021/cr200085w] [Citation(s) in RCA: 820] [Impact Index Per Article: 63.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Edward A. Dennis
- Department of Chemistry and Biochemistry and Pharmacology, School of Medicine, University of California, San Diego, La Jolla, California 92093-0601
| | - Jian Cao
- Department of Chemistry and Biochemistry and Pharmacology, School of Medicine, University of California, San Diego, La Jolla, California 92093-0601
| | - Yuan-Hao Hsu
- Department of Chemistry and Biochemistry and Pharmacology, School of Medicine, University of California, San Diego, La Jolla, California 92093-0601
| | - Victoria Magrioti
- Laboratory of Organic Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - George Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis, Athens 15771, Greece
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Abstract
The human intestine contains huge amounts of nonpathologic bacteria surviving in an environment that is beneficial to both the host and the bacterial populations. When short pauses in oral intake occur with minimal alterations in the mucosa-microbial interface, critical illness, with its attendant acidosis, prolonged gastrointestinal tract starvation, exogenous antibiotics, and breakdown in mucosal defenses, renders the host vulnerable to bacterial challenge and also threatens the survival of the bacteria. This review examines the altered innate and adaptive immunologic host defenses that occur as a result of altered oral or enteral intake and/or injury.
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Affiliation(s)
- Kazuhiko Fukatsu
- Department of Surgery, Surgical Center, The University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 1138655, Japan
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35
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Murakami M, Taketomi Y, Sato H, Yamamoto K. Secreted phospholipase A2 revisited. J Biochem 2011; 150:233-55. [PMID: 21746768 DOI: 10.1093/jb/mvr088] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Phospholipase A(2) (PLA(2)) catalyses the hydrolysis of the sn-2 position of glycerophospholipids to yield fatty acids and lysophospholipids. So far, more than 30 enzymes that possess PLA(2) or related activity have been identified in mammals. About one third of these enzymes belong to the secreted PLA(2) (sPLA(2)) family, which comprises low molecular weight, Ca(2+) requiring, secreted enzymes with a His/Asp catalytic dyad. Individual sPLA(2)s display distinct localizations and enzymatic properties, suggesting their specialized biological roles. However, in contrast to intracellular PLA(2)s, whose roles in signal transduction and membrane homoeostasis have been well documented, the biological roles of sPLA(2)s in vivo have remained obscure until recently. Over the past decade, information fuelled by studies employing knockout and transgenic mice as well as specific inhibitors, in combination with lipidomics, has clarified when and where the different sPLA(2) isoforms are expressed, which isoforms are involved in what types of pathophysiology, and how they exhibit their specific functions. In this review, we highlight recent advances in PLA(2) research, focusing mainly on the physiological functions of sPLA(2)s and their modes of action on 'extracellular' phospholipid targets versus lipid mediator production.
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Affiliation(s)
- Makoto Murakami
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
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Sato H, Isogai Y, Masuda S, Taketomi Y, Miki Y, Kamei D, Hara S, Kobayashi T, Ishikawa Y, Ishii T, Ikeda K, Taguchi R, Ishimoto Y, Suzuki N, Yokota Y, Hanasaki K, Suzuki-Yamamoto T, Yamamoto K, Murakami M. Physiological roles of group X-secreted phospholipase A2 in reproduction, gastrointestinal phospholipid digestion, and neuronal function. J Biol Chem 2011; 286:11632-48. [PMID: 21266581 PMCID: PMC3064216 DOI: 10.1074/jbc.m110.206755] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 01/17/2011] [Indexed: 01/04/2023] Open
Abstract
Although the secreted phospholipase A(2) (sPLA(2)) family has been generally thought to participate in pathologic events such as inflammation and atherosclerosis, relatively high and constitutive expression of group X sPLA(2) (sPLA(2)-X) in restricted sites such as reproductive organs, the gastrointestinal tract, and peripheral neurons raises a question as to the roles played by this enzyme in the physiology of reproduction, digestion, and the nervous system. Herein we used mice with gene disruption or transgenic overexpression of sPLA(2)-X to clarify the homeostatic functions of this enzyme at these locations. Our results suggest that sPLA(2)-X regulates 1) the fertility of spermatozoa, not oocytes, beyond the step of flagellar motility, 2) gastrointestinal phospholipid digestion, perturbation of which is eventually linked to delayed onset of a lean phenotype with reduced adiposity, decreased plasma leptin, and improved muscle insulin tolerance, and 3) neuritogenesis of dorsal root ganglia and the duration of peripheral pain nociception. Thus, besides its inflammatory action proposed previously, sPLA(2)-X participates in physiologic processes including male fertility, gastrointestinal phospholipid digestion linked to adiposity, and neuronal outgrowth and sensing.
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Affiliation(s)
- Hiroyasu Sato
- From the Lipid Metabolism Project, the Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 256-8506
- the Department of Health Chemistry, School of Pharceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555
| | - Yuki Isogai
- From the Lipid Metabolism Project, the Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 256-8506
- the Department of Biology, Faculty of Science, Ochanomizu University, 2-1-1 Otsuka, Bunkyo-ku, Tokyo 112-8610
| | - Seiko Masuda
- From the Lipid Metabolism Project, the Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 256-8506
- the Department of Health Chemistry, School of Pharceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555
| | - Yoshitaka Taketomi
- From the Lipid Metabolism Project, the Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 256-8506
- the Department of Health Chemistry, School of Pharceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555
| | - Yoshimi Miki
- From the Lipid Metabolism Project, the Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 256-8506
- the Department of Health Chemistry, School of Pharceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555
| | - Daisuke Kamei
- the Department of Health Chemistry, School of Pharceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555
| | - Shuntaro Hara
- the Department of Health Chemistry, School of Pharceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555
| | - Tetsuyuki Kobayashi
- the Department of Biology, Faculty of Science, Ochanomizu University, 2-1-1 Otsuka, Bunkyo-ku, Tokyo 112-8610
| | - Yukio Ishikawa
- the Department of Pathology, Toho University School of Medicine, 5-21-16 Omori-Nishi, Ohta-ku, Tokyo 143-8540
| | - Toshiharu Ishii
- the Department of Pathology, Toho University School of Medicine, 5-21-16 Omori-Nishi, Ohta-ku, Tokyo 143-8540
| | - Kazutaka Ikeda
- the Department of Metabolome, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
- the Department of Neutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, Kuboki 111, Souja, Okayama 719-1197, and
| | - Ryo Taguchi
- the Department of Metabolome, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
- CREST and
| | - Yoshikazu Ishimoto
- Shionogi Research Laboratories, Shionogi and Company Ltd, 3-1-1, Futaba-cho, Toyonaka, Osaka 561-0825
| | - Noriko Suzuki
- Shionogi Research Laboratories, Shionogi and Company Ltd, 3-1-1, Futaba-cho, Toyonaka, Osaka 561-0825
| | - Yasunori Yokota
- Shionogi Research Laboratories, Shionogi and Company Ltd, 3-1-1, Futaba-cho, Toyonaka, Osaka 561-0825
| | - Kohji Hanasaki
- Shionogi Research Laboratories, Shionogi and Company Ltd, 3-1-1, Futaba-cho, Toyonaka, Osaka 561-0825
| | - Toshiko Suzuki-Yamamoto
- the Department of Neutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, Kuboki 111, Souja, Okayama 719-1197, and
| | - Kei Yamamoto
- From the Lipid Metabolism Project, the Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 256-8506
| | - Makoto Murakami
- From the Lipid Metabolism Project, the Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 256-8506
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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Murakami M, Sato H, Taketomi Y, Yamamoto K. Integrated lipidomics in the secreted phospholipase A(2) biology. Int J Mol Sci 2011; 12:1474-95. [PMID: 21673902 PMCID: PMC3111613 DOI: 10.3390/ijms12031474] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2011] [Revised: 02/18/2011] [Accepted: 02/24/2011] [Indexed: 12/22/2022] Open
Abstract
Mammalian genomes encode genes for more than 30 phospholipase A(2)s (PLA(2)s) or related enzymes, which are subdivided into several subgroups based on their structures, catalytic mechanisms, localizations and evolutionary relationships. More than one third of the PLA(2) enzymes belong to the secreted PLA(2) (sPLA(2)) family, which consists of low-molecular-weight, Ca(2+)-requiring extracellular enzymes, with a His-Asp catalytic dyad. Individual sPLA(2) isoforms exhibit unique tissue and cellular localizations and enzymatic properties, suggesting their distinct pathophysiological roles. Recent studies using transgenic and knockout mice for several sPLA(2) isoforms, in combination with lipidomics approaches, have revealed their distinct contributions to various biological events. Herein, we will describe several examples of sPLA(2)-mediated phospholipid metabolism in vivo, as revealed by integrated analysis of sPLA(2) transgenic/knockout mice and lipid mass spectrometry. Knowledge obtained from this approach greatly contributes to expanding our understanding of the sPLA(2) biology and pathophysiology.
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Affiliation(s)
- Makoto Murakami
- Lipid Metabolism Project, The Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan; E-Mails: (H.S.); (Y.T.); and (K.Y.)
| | - Hiroyasu Sato
- Lipid Metabolism Project, The Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan; E-Mails: (H.S.); (Y.T.); and (K.Y.)
| | - Yoshitaka Taketomi
- Lipid Metabolism Project, The Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan; E-Mails: (H.S.); (Y.T.); and (K.Y.)
| | - Kei Yamamoto
- Lipid Metabolism Project, The Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan; E-Mails: (H.S.); (Y.T.); and (K.Y.)
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Karray A, Ali YB, Gargouri Y, Bezzine S. Antibacterial properties of chicken intestinal phospholipase A2. Lipids Health Dis 2011; 10:4. [PMID: 21226897 PMCID: PMC3024238 DOI: 10.1186/1476-511x-10-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Accepted: 01/12/2011] [Indexed: 11/23/2022] Open
Abstract
Background The presence of chicken group-IIA PLA2 (ChPLA2-IIA) in the intestinal secretion suggests that this enzyme plays an important role in systemic bactericidal defence. We have analyzed the bactericidal activity of purified ChPLA2-IIA, on several gram-positive and gram-negative bacteria by using the diffusion well and dilution methods. Results ChPLA2-IIA displays potent bactericidal activity against gram-positive bacteria but lacks bactericidal activity against gram negative ones. We have also demonstrated a synergic action of ChPLA2-IIA with lysozyme when added to the bacteria culture prior to ChPLA2-IIA. The bactericidal efficiency of ChPLA2-IIA was shown to be dependent upon the presence of calcium ions and then a correlation could be made to its hydrolytic activity of membrane phospholipids. Interestingly ChPLA2-IIA displays a higher dependence to Ca2+ ions than to Mg2+ions. Conclusion We conclude that the main physiological role of ChPLA2-IIA could be the defence of the intestine against bacterial invasions.
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Affiliation(s)
- Aida Karray
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS Route de Soukra, 3038 Sfax, University of Sfax, Tunisia
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Abu-Maziad A, Schaa K, Bell EF, Dagle JM, Cooper M, Marazita ML, Murray JC. Role of polymorphic variants as genetic modulators of infection in neonatal sepsis. Pediatr Res 2010; 68:323-9. [PMID: 20463618 PMCID: PMC2940937 DOI: 10.1203/pdr.0b013e3181e6a068] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This study is a retrospective, case control study involving 535 preterm infants examining the roles of sequence polymorphisms in genes that mediate host immune responses to bacterial infection in newborn infants. A total of 49 single nucleotide polymorphisms (SNPs) in 19 candidate genes including inflammatory cytokines (IL6, IL10, IL1B, and TNF), cytokine receptors (IL1RN), toll-like receptors (TLR2, TLR4, and TLR5), and cell surface receptors (CD14) were genotyped. Subjects were stratified into three groups (sepsis, suspected sepsis, and control). The data were analyzed using a family-based transmission disequilibrium test. We found that birth weight, gestational age, duration of rupture of membranes, and presence of clinical chorioamnionitis were strongly associated with sepsis. Polymorphisms in TLR2 (rs3804099), TLR5 (rs5744105), IL10 (rs1800896), and PLA2G2A (rs1891320) genes were associated with sepsis. Allelic variants in PLA2G2A and TLR2 were associated with Gram-positive infections, whereas IL10 was associated with Gram-negative infections (p < 0.05). We conclude allelic variations in PLA2G2A, TLR2, TLR5, and IL10 may moderate the predisposition to sepsis in preterm infants.
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Affiliation(s)
- Asmaa Abu-Maziad
- Department of Pediatrics, University of Iowa, Children's Hospital, Iowa City, Iowa 52242, USA
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Type-IIA secreted phospholipase A2 is an endogenous antibiotic-like protein of the host. Biochimie 2010; 92:583-7. [DOI: 10.1016/j.biochi.2010.01.024] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Accepted: 01/29/2010] [Indexed: 12/27/2022]
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Nakahama T, Nakanishi Y, Viscomi AR, Takaya K, Kitamoto K, Ottonello S, Arioka M. Distinct enzymatic and cellular characteristics of two secretory phospholipases A2 in the filamentous fungus Aspergillus oryzae. Fungal Genet Biol 2010; 47:318-31. [PMID: 20045482 DOI: 10.1016/j.fgb.2009.12.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 12/08/2009] [Accepted: 12/28/2009] [Indexed: 11/17/2022]
Abstract
Microbial secretory phospholipases A(2) (sPLA(2)s) are among the last discovered and least known members of this functionally diverse family of enzymes. We analyzed here two sPLA(2)s, named sPlaA and sPlaB, of the filamentous ascomycete Aspergillus oryzae. sPlaA and sPlaB consist of 222 and 160 amino acids, respectively, and share the conserved Cys and catalytic His-Asp residues typical of microbial sPLA(2)s. Two sPLA(2)s differ in pH optimum, Ca(2+) requirement and expression profile. The splaA mRNA was strongly upregulated in response to carbon starvation, oxidative stress and during conidiation, while splaB was constitutively expressed at low levels and was weakly upregulated by heat shock. Experiments with sPLA(2) overexpressing strains demonstrated that two enzymes produce subtly different phospholipid composition variations and also differ in their subcellular localization: sPlaA is most abundant in hyphal tips and secreted to the medium, whereas sPlaB predominantly localizes to the ER-like intracellular compartment. Both sPLA(2) overexpressing strains were defective in conidiation, which was more pronounced for sPlaB overexpressors. Although no major morphological abnormality was detected in either DeltasplaA or DeltasplaB mutants, hyphal growth of DeltasplaB, but not that of DeltasplaA, displayed increased sensitivity to H(2)O(2) treatment. These data indicate that two A. oryzae sPLA(2) enzymes display distinct, presumably non-redundant, physiological functions.
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Affiliation(s)
- Tomoyuki Nakahama
- Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Raymond B, Ravaux L, Mémet S, Wu Y, Sturny-Leclère A, Leduc D, Denoyelle C, Goossens PL, Payá M, Raymondjean M, Touqui L. Anthrax lethal toxin down-regulates type-IIA secreted phospholipase A(2) expression through MAPK/NF-kappaB inactivation. Biochem Pharmacol 2009; 79:1149-55. [PMID: 19962969 DOI: 10.1016/j.bcp.2009.11.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Revised: 11/27/2009] [Accepted: 11/30/2009] [Indexed: 10/20/2022]
Abstract
Bacillus anthracis, the etiological agent of anthrax, produces lethal toxin (LT) that displays a metallo-proteolytic activity toward the N-terminus of the MAPK-kinases. We have previously shown that secreted type-IIA phospholipase A(2) (sPLA(2)-IIA) exhibits potent anthracidal activity. In vitro expression of sPLA(2)-IIA in guinea pig alveolar macrophages (AMs), the major source of this enzyme in lung tissues, is inhibited by LT. Here, we examined the mechanisms involved in sPLA(2)-IIA inhibition by LT. We first showed that chemical inhibitors of p38 and ERK MAPKs reduced sPLA(2)-IIA expression in AMs indicating that these kinases play a role in sPLA(2)-IIA expression. LT inhibited IL-1beta-induced p38 phosphorylation as well as sPLA(2)-IIA promoter activity in CHO cells. Inhibition of sPLA(2)-IIA promoter activity was mimicked by co-transfection with dominant negative construct of p38 (DN-p38) and reversed by the active form of p38-MAPK (AC-p38). Both LT and DN-p38 decreased IL-1beta-induced NF-kappaB luciferase activity. This contrasted with the effect of AC-p38, which enhanced this activity. However, neither LT nor specific p-38 inhibitor interfered with LPS-induced IkappaBalpha degradation or NF-kappaB nuclear translocation in AMs. Subcutaneous administration of LT to guinea pig before LPS challenge reduced sPLA(2)-IIA levels in broncho-alveolar lavages and ears. We conclude that sPLA(2)-IIA expression is induced via a sequential MAPK-NF-kappaB activation and that LT inhibits this expression likely by interfering with the transactivation of NF-kappaB in the nucleus. This inhibition, which is operating both in vitro and in vivo, may represent a mechanism by which B. anthracis subvert host defense.
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Papayannopoulos V, Zychlinsky A. NETs: a new strategy for using old weapons. Trends Immunol 2009; 30:513-21. [PMID: 19699684 DOI: 10.1016/j.it.2009.07.011] [Citation(s) in RCA: 434] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 07/16/2009] [Accepted: 07/21/2009] [Indexed: 02/06/2023]
Abstract
As key players in the host innate immune response, neutrophils are recruited to sites of infection and constitute the first line of defense. They employ three strategies to eliminate invading microbes: microbial uptake, the secretion of antimicrobials, and the recently described release of Neutrophil Extracellular Traps (NETs). Composed of decondensed chromatin and antimicrobial proteins, NETs bind and kill a variety of microbes including bacteria, fungi, and parasites. In addition to using a repertoire of known antimicrobials, NETs incorporate histones into the antimicrobial arsenal. Furthermore, NETs may contribute to microbial containment by forming a physical barrier and a scaffold, to enhance antimicrobial synergy while minimizing damage to host tissues. Their role in innate immunity is only now being uncovered.
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Goossens PL. Animal models of human anthrax: the Quest for the Holy Grail. Mol Aspects Med 2009; 30:467-80. [PMID: 19665473 DOI: 10.1016/j.mam.2009.07.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 07/30/2009] [Indexed: 01/13/2023]
Abstract
Anthrax is rare among humans, few data can be collected from infected individuals and they provide a fragmentary view of the dynamics of infection and human host-pathogen interactions. Therefore, the development of animal models is necessary. Anthrax has the particularity of being a toxi-infection, a combination of infection and toxemia. The ideal animal model would explore these two different facets and mimic human disease as much as possible. In the past decades, the main effort has been focused on modelling of inhalational anthrax and the perception of specific aspects of the infection has evolved in recent years. In this review, we consider criteria which can lead to the most appropriate choice of a given animal species for modelling human anthrax. We will highlight the positive input and limitations of different models and show that they are not mutually exclusive. On the contrary, their contribution to anthrax research can be more rewarding when taken in synergy. We will also present a reappraisal of inhalational anthrax and propose reflections on key points, such as portal of entry, connections between mediastinal lymph nodes, pleura and lymphatic drainage.
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Affiliation(s)
- Pierre L Goossens
- Institut Pasteur, Toxines et Pathogénie Bactérienne, CNRS URA 2172, 28 rue du Docteur Roux, 75724 Paris cedex 15, France.
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Abstract
PURPOSE To define factors that protect the eye from Staphylococcus aureus keratitis and limit tissue damage once keratitis occurs. METHODS Rabbit tears were analyzed for bactericidal and phospholipase A(2) (PLA(2)) activities on S. aureus. Inhibition by spermidine of PLA(2) anti-staphylococcal activity in tears was tested in vitro and in vivo. Rabbits immunized with heat-inactivated alpha-toxin were challenged with intrastromal injection of S. aureus. RESULTS Arachidonic acid was cleaved from S. aureus by purified PLA( 2) or rabbit tears. Spermidine inhibited these reactions in vitro and facilitated keratitis in vivo. PLA(2) activity decreased with advanced age and shortly following sleep, but increased with keratitis. Antibody to alpha-toxin significantly reduced corneal damage and epithelial cell sloughing during keratitis. CONCLUSIONS PLA(2) is a major host-defense component of rabbit tears. Alpha-toxin is a major mediator of corneal damage, and antibody to alpha-toxin reduces pathologic changes during keratitis.
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Affiliation(s)
- Richard J O'Callaghan
- Department of Microbiology, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA.
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Kitsiouli E, Nakos G, Lekka ME. Phospholipase A2 subclasses in acute respiratory distress syndrome. Biochim Biophys Acta Mol Basis Dis 2009; 1792:941-53. [PMID: 19577642 DOI: 10.1016/j.bbadis.2009.06.007] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Revised: 06/25/2009] [Accepted: 06/25/2009] [Indexed: 01/12/2023]
Abstract
Phospholipases A2 (PLA2) catalyse the cleavage of fatty acids esterified at the sn-2 position of glycerophospholipids. In acute lung injury-acute respiratory distress syndrome (ALI-ARDS) several distinct isoenzymes appear in lung cells and fluid. Some are capable to trigger molecular events leading to enhanced inflammation and lung damage and others have a role in lung surfactant recycling preserving lung function: Secreted forms (groups sPLA2-IIA, -V, -X) can directly hydrolyze surfactant phospholipids. Cytosolic PLA2 (cPLA2-IVA) requiring Ca2+ has a preference for arachidonate, the precursor of eicosanoids which participate in the inflammatory response in the lung. Ca(2+)-independent intracellular PLA2s (iPLA2) take part in surfactant phospholipids turnover within alveolar cells. Acidic Ca(2+)-independent PLA2 (aiPLA2), of lysosomal origin, has additionally antioxidant properties, (peroxiredoxin VI activity), and participates in the formation of dipalmitoyl-phosphatidylcholine in lung surfactant. PAF-AH degrades PAF, a potent mediator of inflammation, and oxidatively fragmented phospholipids but also leads to toxic metabolites. Therefore, the regulation of PLA2 isoforms could be a valuable approach for ARDS treatment.
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Affiliation(s)
- Eirini Kitsiouli
- Department of Biological Applications and Technologies, School of Sciences and Technologies, University of Ioannina, Greece
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Selvin J. Exploring the antagonistic producer Streptomyces MSI051: implications of polyketide synthase gene type II and a ubiquitous defense enzyme phospholipase A2 in the host sponge Dendrilla nigra. Curr Microbiol 2009; 58:459-63. [PMID: 19130125 DOI: 10.1007/s00284-008-9343-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2008] [Revised: 12/03/2008] [Accepted: 12/03/2008] [Indexed: 11/25/2022]
Abstract
To explore the functional role of the antagonistic producer strain Streptomyces dendra sp. nov. MSI051 in the host sponge Dendrilla nigra, hypothetical factors including the antagonistic potential of MSI051 against biofilm bacteria and a ubiquitous defense enzyme phospholipase A2 (PLA2) in host sponge as well as in bacterial symbiont MSI051 were determined. The host sponge D. nigra and associated bacterial symbiont MSI051 contained high levels of PLA2. The host sponge showed PLA2 activity to the extent of 1032 U/L, with a specific activity of 2021 U/g, and strain MSI051 showed similar activity. The findings of the present study suggest that PLA2 in the sponge-associated bacteria might have an integrated functional role in the host defense system of marine sponges. This report may be the first on the role of PLA2 activity in sponge-associated bacteria. Isolate MSI051 was a potential antagonistic producer which showed a broad spectrum of antibacterial activity. Polyketide synthase gene type II in MSI051 ultimately evidenced the antagonistic potential. Antimicrobial activity was found to be positively skewed toward biofilm bacteria. This implies a functional role of MSI051 in the protection of host sponge against fouling processes.
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Affiliation(s)
- Joseph Selvin
- Marine Bioprospecting Laboratory, Department of Microbiology, Bharathidasan University, Tiruchirappalli, India.
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Titsworth WL, Liu NK, Xu XM. Role of secretory phospholipase a(2) in CNS inflammation: implications in traumatic spinal cord injury. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2008; 7:254-69. [PMID: 18673210 DOI: 10.2174/187152708784936671] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Secretory phospholipases A(2) (sPLA(2)s) are a subfamily of lipolytic enzymes which hydrolyze the acyl bond at the sn-2 position of glycerophospholipids to produce free fatty acids and lysophospholipids. These products are precursors of bioactive eicosanoids and platelet-activating factor (PAF). The hydrolysis of membrane phospholipids by PLA(2) is a rate-limiting step for generation of eicosanoids and PAF. To date, more than 10 isozymes of sPLA(2) have been found in the mammalian central nervous system (CNS). Under physiological conditions, sPLA(2)s are involved in diverse cellular responses, including host defense, phospholipid digestion and metabolism. However, under pathological situations, increased sPLA(2) activity and excessive production of free fatty acids and their metabolites may lead to inflammation, loss of membrane integrity, oxidative stress, and subsequent tissue injury. Emerging evidence suggests that sPLA(2) plays a role in the secondary injury process after traumatic or ischemic injuries in the brain and spinal cord. Importantly, sPLA(2) may act as a convergence molecule that mediates multiple key mechanisms involved in the secondary injury since it can be induced by multiple toxic factors such as inflammatory cytokines, free radicals, and excitatory amino acids, and its activation and metabolites can exacerbate the secondary injury. Blocking sPLA(2) action may represent a novel and efficient strategy to block multiple injury pathways associated with the CNS secondary injury. This review outlines the current knowledge of sPLA(2) in the CNS with emphasis placed on the possible roles of sPLA(2) in mediating CNS injuries, particularly the traumatic and ischemic injuries in the brain and spinal cord.
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Affiliation(s)
- W Lee Titsworth
- Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, KY 40202, USA
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Abstract
Introduction The secretory phospholipase A2 (sPLA2) family provides a seemingly endless array of potential biological functions that is only beginning to be appreciated. In humans, this family comprises 9 different members that vary in their tissue distribution, hydrolytic activity, and phospholipid substrate specificity. Through their lipase activity, these enzymes trigger various cell-signaling events to regulate cellular functions, directly kill bacteria, or modulate inflammatory responses. In addition, some sPLA2’s are high affinity ligands for cellular receptors. Objective This review merely scratches the surface of some of the actions of sPLA2s in innate immunity, inflammation, and atherosclerosis. The goal is to provide an overview of recent findings involving sPLA2s and to point to potential pathophysiologic mechanisms that may become targets for therapy.
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Sato H, Kato R, Isogai Y, Saka GI, Ohtsuki M, Taketomi Y, Yamamoto K, Tsutsumi K, Yamada J, Masuda S, Ishikawa Y, Ishii T, Kobayashi T, Ikeda K, Taguchi R, Hatakeyama S, Hara S, Kudo I, Itabe H, Murakami M. Analyses of group III secreted phospholipase A2 transgenic mice reveal potential participation of this enzyme in plasma lipoprotein modification, macrophage foam cell formation, and atherosclerosis. J Biol Chem 2008; 283:33483-97. [PMID: 18801741 DOI: 10.1074/jbc.m804628200] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Among the many mammalian secreted phospholipase A2 (sPLA2) enzymes, PLA2G3 (group III secreted phospholipase A2) is unique in that it possesses unusual N- and C-terminal domains and in that its central sPLA2 domain is homologous to bee venom PLA2 rather than to other mammalian sPLA2s. To elucidate the in vivo actions of this atypical sPLA2, we generated transgenic (Tg) mice overexpressing human PLA2G3. Despite marked increases in PLA2 activity and mature 18-kDa PLA2G3 protein in the circulation and tissues, PLA2G3 Tg mice displayed no apparent abnormality up to 9 months of age. However, alterations in plasma lipoproteins were observed in PLA2G3 Tg mice compared with control mice. In vitro incubation of low density (LDL) and high density (HDL) lipoproteins with several sPLA2s showed that phosphatidylcholine was efficiently converted to lysophosphatidylcholine by PLA2G3 as well as by PLA2G5 and PLA2G10, to a lesser extent by PLA2G2F, and only minimally by PLA2G2A and PLA2G2E. PLA2G3-modified LDL, like PLA2G5- or PLA2G10-treated LDL, facilitated the formation of foam cells from macrophages ex vivo. Accumulation of PLA2G3 was detected in the atherosclerotic lesions of humans and apoE-deficient mice. Furthermore, following an atherogenic diet, aortic atherosclerotic lesions were more severe in PLA2G3 Tg mice than in control mice on the apoE-null background, in combination with elevated plasma lysophosphatidylcholine and thromboxane A2 levels. These results collectively suggest a potential functional link between PLA2G3 and atherosclerosis, as has recently been proposed for PLA2G5 and PLA2G10.
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Affiliation(s)
- Hiroyasu Sato
- Biomembrane Signaling Project, Tokyo Metropolitan Institute of Medical Science, 3-18-22 Honkomagome, Tokyo 113-8613, Japan
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