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Murakami M. Extracellular vesicles as a hydrolytic platform of secreted phospholipase A 2. Biochim Biophys Acta Mol Cell Biol Lipids 2024; 1869:159536. [PMID: 39032626 DOI: 10.1016/j.bbalip.2024.159536] [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: 05/31/2024] [Revised: 07/04/2024] [Accepted: 07/17/2024] [Indexed: 07/23/2024]
Abstract
Extracellular vesicles (EVs) represent small vesicles secreted from cells, including exosomes (40-150 nm in diameter), which are released via the multivesicular endosomal pathway, and microvesicles and ectosomes (100-1000 nm), which are produced by plasma membrane budding. Broadly, EVs also include vesicles generated from dying cells, such as apoptotic bodies (5-10 μm), as well as exomeres (< 50 nm), which are very small, non-membranous nanoparticles. EVs play important roles in cell-to-cell signaling in various aspects of cancer, immunity, metabolism, and so on by transferring proteins, microRNAs (miRNAs), and metabolites as cargos from donor cells to recipient cells. Although lipids are one of the major components of EVs, they have long been recognized as merely the "wall" that partitions the lumen of the vesicle from the outside. However, it has recently become obvious that lipid composition of EVs influences their properties and functions, that EVs act as a carrier of a variety of lipid mediators, and that lipid mediators are produced in EV membranes by the hydrolytic action of secreted phospholipase A2s (sPLA2s). In this article, we will make an overview of the roles of lipids in EVs, with a particular focus on sPLA2-driven mobilization of lipid mediators from EVs and its biological significance.
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Affiliation(s)
- Makoto Murakami
- Laboratory of Microenvironmental and Metabolic Health Science, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
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2
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Sato H, Taketomi Y, Murase R, Park J, Hosomi K, Sanada TJ, Mizuguchi K, Arita M, Kunisawa J, Murakami M. Group X phospholipase A 2 links colonic lipid homeostasis to systemic metabolism via host-microbiota interaction. Cell Rep 2024; 43:114752. [PMID: 39298315 DOI: 10.1016/j.celrep.2024.114752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 07/30/2024] [Accepted: 08/29/2024] [Indexed: 09/21/2024] Open
Abstract
The gut microbiota influences physiological functions of the host, ranging from the maintenance of local gut homeostasis to systemic immunity and metabolism. Secreted phospholipase A2 group X (sPLA2-X) is abundantly expressed in colonic epithelial cells but is barely detectable in metabolic and immune tissues. Despite this distribution, sPLA2-X-deficient (Pla2g10-/-) mice displayed variable obesity-related phenotypes that were abrogated after treatment with antibiotics or cohousing with Pla2g10+/+ mice, suggesting the involvement of the gut microbiota. Under housing conditions where Pla2g10-/- mice showed aggravation of diet-induced obesity and insulin resistance, they displayed increased colonic inflammation and epithelial damage, reduced production of polyunsaturated fatty acids (PUFAs) and lysophospholipids, decreased abundance of several Clostridium species, and reduced levels of short-chain fatty acids (SCFAs). These obesity-related phenotypes in Pla2g10-/- mice were reversed by dietary supplementation with ω3 PUFAs or SCFAs. Thus, colonic sPLA2-X orchestrates ω3 PUFA-SCFA interplay via modulation of the gut microbiota, thereby secondarily affecting systemic metabolism.
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Affiliation(s)
- Hiroyasu Sato
- Laboratory of Microenvironmental and Metabolic Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan; Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Yoshitaka Taketomi
- Laboratory of Microenvironmental and Metabolic Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan; Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Remi Murase
- Division of Cancer Genome and Pharmacotherapy, Department of Clinical Pharmacy, School of Pharmacy, Showa University, Tokyo 142-8555, Japan
| | - Jonguk Park
- Laboratory of Bioinformatics, Artificial Intelligence Center for Health and Biomedical Research, Osaka 567-0085, Japan
| | - Koji Hosomi
- Laboratory of Vaccine Materials and Laboratory of Gut Environmental System, Microbial Research Center for Health and Medicine, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka 567-0085, Japan
| | - Takayuki Jujo Sanada
- Laboratory of Vaccine Materials and Laboratory of Gut Environmental System, Microbial Research Center for Health and Medicine, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka 567-0085, Japan
| | - Kenji Mizuguchi
- Laboratory of Bioinformatics, Artificial Intelligence Center for Health and Biomedical Research, Osaka 567-0085, Japan; Institute for Protein Research, Osaka University, Osaka 565-0871, Japan
| | - Makoto Arita
- Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa 230-0045, Japan; Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Tokyo 105-8512, Japan; Human Biology-Microbiome-Quantum Research Center (WPI-Bio2Q), Keio University, Tokyo, Japan
| | - Jun Kunisawa
- Laboratory of Vaccine Materials and Laboratory of Gut Environmental System, Microbial Research Center for Health and Medicine, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka 567-0085, Japan
| | - Makoto Murakami
- Laboratory of Microenvironmental and Metabolic Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan; Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Tokyo 100-0004, Japan.
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3
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Zhang T, Yu W, Cheng X, Yeung J, Ahumada V, Norris PC, Pearson MJ, Yang X, van Deursen W, Halcovich C, Nassar A, Vesely MD, Zhang Y, Zhang JP, Ji L, Flies DB, Liu L, Langermann S, LaRochelle WJ, Humphrey R, Zhao D, Zhang Q, Zhang J, Gu R, Schalper KA, Sanmamed MF, Chen L. Up-regulated PLA2G10 in cancer impairs T cell infiltration to dampen immunity. Sci Immunol 2024; 9:eadh2334. [PMID: 38669316 DOI: 10.1126/sciimmunol.adh2334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 10/19/2023] [Accepted: 04/04/2024] [Indexed: 04/28/2024]
Abstract
T cells are often absent from human cancer tissues during both spontaneously induced immunity and therapeutic immunotherapy, even in the presence of a functional T cell-recruiting chemokine system, suggesting the existence of T cell exclusion mechanisms that impair infiltration. Using a genome-wide in vitro screening platform, we identified a role for phospholipase A2 group 10 (PLA2G10) protein in T cell exclusion. PLA2G10 up-regulation is widespread in human cancers and is associated with poor T cell infiltration in tumor tissues. PLA2G10 overexpression in immunogenic mouse tumors excluded T cells from infiltration, resulting in resistance to anti-PD-1 immunotherapy. PLA2G10 can hydrolyze phospholipids into small lipid metabolites, thus inhibiting chemokine-mediated T cell mobility. Ablation of PLA2G10's enzymatic activity enhanced T cell infiltration and sensitized PLA2G10-overexpressing tumors to immunotherapies. Our study implicates a role for PLA2G10 in T cell exclusion from tumors and suggests a potential target for cancer immunotherapy.
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Affiliation(s)
- Tianxiang Zhang
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Weiwei Yu
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Xiaoxiao Cheng
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Jacky Yeung
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Viviana Ahumada
- Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
| | | | | | - Xuan Yang
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | | | - Christina Halcovich
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Ala Nassar
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Matthew D. Vesely
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Dermatology, Yale University School of Medicine, New Haven, CT, USA
| | - Yu Zhang
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Jian-Ping Zhang
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Lan Ji
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | | | | | | | | | | | - Dejian Zhao
- Yale Center for Genome Analysis, Yale University, New Haven, CT, USA
| | - Qiuyu Zhang
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Jindong Zhang
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Runxia Gu
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Kurt A Schalper
- Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
| | - Miguel F Sanmamed
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
- Program of Immunology and Immunotherapy, Center for Applied Medical Research, University of Navarra, Pamplona, Spain
| | - Lieping Chen
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
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4
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Murakami M, Sato H, Taketomi Y. Modulation of immunity by the secreted phospholipase A 2 family. Immunol Rev 2023; 317:42-70. [PMID: 37035998 DOI: 10.1111/imr.13205] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/23/2023] [Accepted: 03/28/2023] [Indexed: 04/11/2023]
Abstract
Among the phospholipase A2 (PLA2 ) superfamily, which typically catalyzes the sn-2 hydrolysis of phospholipids to yield fatty acids and lysophospholipids, the secreted PLA2 (sPLA2 ) family contains 11 isoforms in mammals. Individual sPLA2 s have unique enzymatic specificity toward fatty acids and polar heads of phospholipid substrates and display distinct tissue/cellular distributions, suggesting their distinct physiological functions. Recent studies using knockout and/or transgenic mice for a full set of sPLA2 s have revealed their roles in modulation of immunity and related disorders. Application of mass spectrometric lipidomics to these mice has enabled to identify target substrates and products of individual sPLA2 s in given tissue microenvironments. sPLA2 s hydrolyze not only phospholipids in the plasma membrane of activated, damaged or dying mammalian cells, but also extracellular phospholipids such as those in extracellular vesicles, microbe membranes, lipoproteins, surfactants, and dietary phospholipids, thereby exacerbating or ameliorating various diseases. The actions of sPLA2 s are dependent on, or independent of, the generation of fatty acid- or lysophospholipid-derived lipid mediators according to the pathophysiological contexts. In this review, we make an overview of our current understanding of the roles of individual sPLA2 s in various immune responses and associated diseases.
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Affiliation(s)
- 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
- AMED-CREST, Japan Agency for Medical Research and Development, Tokyo, Japan
| | - Hiroyasu Sato
- Laboratory of Microenvironmental and Metabolic Health Science, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yoshitaka Taketomi
- Laboratory of Microenvironmental and Metabolic Health Science, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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5
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Yamamoto K, Hakoi H, Nomura S, Murakami M. The Roles of sPLA 2s in Skin Homeostasis and Disease. Biomolecules 2023; 13:biom13040668. [PMID: 37189415 DOI: 10.3390/biom13040668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/21/2023] [Accepted: 04/10/2023] [Indexed: 05/17/2023] Open
Abstract
Among the phospholipase A2 (PLA2) family, the secreted PLA2 (sPLA2) family in mammals contains 11 members that exhibit unique tissue or cellular distributions and enzymatic properties. Current studies using knockout and/or transgenic mice for a nearly full set of sPLA2s, in combination with comprehensive lipidomics, have revealed the diverse pathophysiological roles of sPLA2s in various biological events. Individual sPLA2s exert specific functions within tissue microenvironments, likely through the hydrolysis of extracellular phospholipids. Lipids are an essential biological component for skin homeostasis, and disturbance of lipid metabolism by deletion or overexpression of lipid-metabolizing enzymes or lipid-sensing receptors often leads to skin abnormalities that are easily visible on the outside. Over the past decades, our studies using knockout and transgenic mice for various sPLA2s have uncovered several new aspects of these enzymes as modulators of skin homeostasis and disease. This article summarizes the roles of several sPLA2s in skin pathophysiology, providing additional insight into the research fields of sPLA2s, lipids, and skin biology.
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Affiliation(s)
- Kei Yamamoto
- Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-jyosanjima, Tokushima 770-8513, Japan
| | - Haruka Hakoi
- Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-jyosanjima, Tokushima 770-8513, Japan
| | - Saki Nomura
- Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-jyosanjima, Tokushima 770-8513, Japan
| | - Makoto Murakami
- Laboratory of Microenvironmental and Metabolic Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo (UTokyo), 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
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Alonazi M, Karray A, Jallouli R, Ben Bacha A. Biochemical, Kinetic and Biological Properties of Group V Phospholipase A2 from Dromedary. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27113437. [PMID: 35684381 PMCID: PMC9182273 DOI: 10.3390/molecules27113437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/19/2022] [Accepted: 05/23/2022] [Indexed: 11/16/2022]
Abstract
Secretory group V phospholipase A2 (PLA2-V) is known to be involved in inflammatory processes in cellular studies, nevertheless, the biochemical and the enzymatic characteristics of this important enzyme have been unclear yet. We reported, as a first step towards understanding the biochemical properties, catalytic characteristics, antimicrobial and cytotoxic effects of this PLA2, the production of PLA2-V from dromedary. The obtained DrPLA2-V has an absolute requirement for Ca2+ and NaTDC for enzymatic activity with an optimum pH of 9 and temperature of 45 °C with phosphatidylethanolamine as a substrate. Kinetic parameters showed that Kcat/Kmapp is 2.6 ± 0.02 mM−1 s−1. The enzyme was found to display potent Gram-positive bactericidal activity (with IC50 values of about 5 µg/mL) and antifungal activity (with IC50 values of about 25 µg/mL)in vitro. However, the purified enzyme did not display a cytotoxic effect against cancer cells.
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Affiliation(s)
- Mona Alonazi
- Biochemistry Department, Science College, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia;
| | - Aida Karray
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS Route de Soukra, Université de Sfax-Tunisia, Sfax 3038, Tunisia;
| | - Raida Jallouli
- Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada;
| | - Abir Ben Bacha
- Biochemistry Department, Science College, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia;
- Laboratory of Plant Biotechnology Applied to Crop Improvement, Faculty of Science of Sfax, University of Sfax, Sfax 3038, Tunisia
- Correspondence: ; Tel.: +966-504-784-639
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Old but New: Group IIA Phospholipase A 2 as a Modulator of Gut Microbiota. Metabolites 2022; 12:metabo12040352. [PMID: 35448539 PMCID: PMC9029192 DOI: 10.3390/metabo12040352] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 12/15/2022] Open
Abstract
Among the phospholipase A2 (PLA2) superfamily, the secreted PLA2 (sPLA2) family contains 11 mammalian isoforms that exhibit unique tissue or cellular distributions and enzymatic properties. Current studies using sPLA2-deficient or -overexpressed mouse strains, along with mass spectrometric lipidomics to determine sPLA2-driven lipid pathways, have revealed the diverse pathophysiological roles of sPLA2s in various biological events. In general, individual sPLA2s exert their specific functions within tissue microenvironments, where they are intrinsically expressed through hydrolysis of extracellular phospholipids. Recent studies have uncovered a new aspect of group IIA sPLA2 (sPLA2-IIA), a prototypic sPLA2 with the oldest research history among the mammalian PLA2s, as a modulator of the gut microbiota. In the intestine, Paneth cell-derived sPLA2-IIA acts as an antimicrobial protein to shape the gut microbiota, thereby secondarily affecting inflammation, allergy, and cancer in proximal and distal tissues. Knockout of intestinal sPLA2-IIA in BALB/c mice leads to alterations in skin cancer, psoriasis, and anaphylaxis, while overexpression of sPLA2-IIA in Pla2g2a-null C57BL/6 mice induces systemic inflammation and exacerbates arthritis. These phenotypes are associated with notable changes in gut microbiota and fecal metabolites, are variable in different animal facilities, and are abrogated after antibiotic treatment, co-housing, or fecal transfer. These studies open a new mechanistic action of this old sPLA2 and add the sPLA2 family to the growing list of endogenous factors capable of affecting the microbe–host interaction and thereby systemic homeostasis and diseases.
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Scott KF, Mann TJ, Fatima S, Sajinovic M, Razdan A, Kim RR, Cooper A, Roohullah A, Bryant KJ, Gamage KK, Harman DG, Vafaee F, Graham GG, Church WB, Russell PJ, Dong Q, de Souza P. Human Group IIA Phospholipase A 2-Three Decades on from Its Discovery. Molecules 2021; 26:molecules26237267. [PMID: 34885848 PMCID: PMC8658914 DOI: 10.3390/molecules26237267] [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: 11/08/2021] [Revised: 11/21/2021] [Accepted: 11/22/2021] [Indexed: 12/13/2022] Open
Abstract
Phospholipase A2 (PLA2) enzymes were first recognized as an enzyme activity class in 1961. The secreted (sPLA2) enzymes were the first of the five major classes of human PLA2s to be identified and now number nine catalytically-active structurally homologous proteins. The best-studied of these, group IIA sPLA2, has a clear role in the physiological response to infection and minor injury and acts as an amplifier of pathological inflammation. The enzyme has been a target for anti-inflammatory drug development in multiple disorders where chronic inflammation is a driver of pathology since its cloning in 1989. Despite intensive effort, no clinically approved medicines targeting the enzyme activity have yet been developed. This review catalogues the major discoveries in the human group IIA sPLA2 field, focusing on features of enzyme function that may explain this lack of success and discusses future research that may assist in realizing the potential benefit of targeting this enzyme. Functionally-selective inhibitors together with isoform-selective inhibitors are necessary to limit the apparent toxicity of previous drugs. There is also a need to define the relevance of the catalytic function of hGIIA to human inflammatory pathology relative to its recently-discovered catalysis-independent function.
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Affiliation(s)
- Kieran F. Scott
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- Correspondence: ; Tel.: +61-2-8738-9026
| | - Timothy J. Mann
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
| | - Shadma Fatima
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- School of Biotechnology and Biological Sciences, University of New South Wales (UNSW Sydney), Sydney, NSW 2052, Australia;
| | - Mila Sajinovic
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
| | - Anshuli Razdan
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
| | - Ryung Rae Kim
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia; (R.R.K.); (W.B.C.)
| | - Adam Cooper
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- Liverpool Cancer Therapy Centre, Liverpool Hospital, Liverpool, NSW 2170, Australia
| | - Aflah Roohullah
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- Liverpool Cancer Therapy Centre, Liverpool Hospital, Liverpool, NSW 2170, Australia
| | - Katherine J. Bryant
- School of Photovoltaic and Renewable Energy Engineering, UNSW Sydney, Sydney, NSW 2052, Australia;
| | - Kasuni K. Gamage
- School of Science, Western Sydney University, Campbelltown, NSW 2560, Australia; (K.K.G.); (D.G.H.)
| | - David G. Harman
- School of Science, Western Sydney University, Campbelltown, NSW 2560, Australia; (K.K.G.); (D.G.H.)
| | - Fatemeh Vafaee
- School of Biotechnology and Biological Sciences, University of New South Wales (UNSW Sydney), Sydney, NSW 2052, Australia;
- UNSW Data Science Hub, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Garry G. Graham
- Department of Clinical Pharmacology, St Vincent’s Hospital Sydney, Darlinghurst, NSW 2010, Australia;
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - W. Bret Church
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia; (R.R.K.); (W.B.C.)
| | - Pamela J. Russell
- Australian Prostate Cancer Research Centre—QUT, Brisbane, QLD 4102, Australia;
| | - Qihan Dong
- Chinese Medicine Anti-Cancer Evaluation Program, Greg Brown Laboratory, Central Clinical School and Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia;
| | - Paul de Souza
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- School of Medicine, UNSW Sydney, Sydney, NSW 2052, Australia
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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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Tjørnelund HD, Madsen JJ, Peters GHJ. Water-Intake and Water-Molecule Paths to the Active Site of Secretory Phospholipase A 2 Studied Using MD Simulations and the Tracking Tool AQUA-DUCT. J Phys Chem B 2020; 124:1881-1891. [PMID: 32064878 DOI: 10.1021/acs.jpcb.9b10837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Secretory phospholipases A2 (sPLA2s) are a subclass of enzymes that catalyze the hydrolysis at the sn-2 position of glycerophospholipids, producing free fatty acids and lysophospholipids. In this study, different phospholipids with structural modifications close to the scissile sn-2 ester bond were studied to determine the effect of the structural changes on the formation of the Michaelis-Menten complex and the water entry/exit pathways using molecular dynamics simulations and the computational tracking tool AQUA-DUCT. Structural modifications include methylation, dehydrogenation, and polarization close to the sn-2 scissile bond. We found that all water molecules reaching the active site of sPLA2-IIA pass by the aromatic residues Phe5 and Tyr51 and enter the active site through an active-site cleft. The relative amount of water available for the enzymatic reaction of the different phospholipid-sPLA2 complexes was determined together with the distance between key atoms in the catalytic machinery. The results showed that (Z)-unsaturated phospholipid is a good substrate for sPLA2-IIA. The computational results are in good agreement with previously reported experimental data on the ability of sPLA2-IIA to hydrolyze liposomes made from the different phospholipids, and the results provide new insights into the necessary active-site solvation of the Michaelis-Menten complex and can pave the road for rational design in engineering applications.
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Affiliation(s)
- Helena D Tjørnelund
- Department of Chemistry, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Jesper J Madsen
- Department of Global Health, College of Public Health, University of South Florida, Tampa, Florida 33620, United States
| | - Günther H J Peters
- Department of Chemistry, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
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11
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Hydrolysis of three different head groups phospholipids by chicken group V phospholipase A2 using the monomolecular film technique. Biosci Rep 2020; 40:221815. [PMID: 31919493 PMCID: PMC6974423 DOI: 10.1042/bsr20192053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 11/08/2019] [Accepted: 11/22/2019] [Indexed: 11/17/2022] Open
Abstract
The kinetic aspects of lipolysis by pulmonary phospholipase A2 (ChPLA2-V), chicken intestinal phospholipase A2 (ChPLA2-IIA) and chicken pancreatic phospholipase A2 (ChPLA2-IB), from chicken have been compared using the monomolecular films technique, on short-chain phospholipids (with three different head groups) and on long-chain phospholipids. The main conclusions from our experimental data indicate that the maximum catalytic activities of ChPLA2-V on 1,2 phosphatidylcholine and 1,2 phosphatidylethanolamine reached 15.26 and 36.12 moles/cm2.min.mM, respectively, at a pressure of 15 and 35 dynes/cm, respectively. Whereas, those of ChPLA2-IB were 3.58 (at the pressure of 20 dynes/cm) and 4.9 moles/cm2.min.mM. However, hydrolysis of phosphatidylglycerol monolayers (C12PG), were very much higher compared with all the substrates tested with 122 moles/cm2.min. Surprisingly, the hydrolysis rate of ChPLA2-V on long-chain phosphatidylglycerol (C18PG) was very low (1.45 moles/cm2.min) compared with all tested substrates, even with the use of p-cyclodextrin. And thus, the fatty acid preference of ChPLA2-V was 2-decanoyl > 2-oleoyl with a PG head group. In order to gain significant correlations between enzyme’s structures and their relative functions, we tried to examine the surface electrostatic potentials of the various secreted phospholipase 2 (sPLA2) from chicken. In the present study, we detailed that the substrate affinity, specificity and the hydrolysis rates of sPLA2 at each interface is governed by the surface electrostatic potentials and hydrophobic interactions operative at this surface.
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12
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Sukocheva O, Menschikowski M, Hagelgans A, Yarla NS, Siegert G, Reddanna P, Bishayee A. Current insights into functions of phospholipase A2 receptor in normal and cancer cells: More questions than answers. Semin Cancer Biol 2019; 56:116-127. [PMID: 29104026 DOI: 10.1016/j.semcancer.2017.11.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 10/18/2017] [Accepted: 11/01/2017] [Indexed: 02/08/2023]
Abstract
Lipid signaling network was proposed as a potential target for cancer prevention and treatment. Several recent studies revealed that phospholipid metabolising enzyme, phospholipase A2 (PLA2), is a critical regulator of cancer accelerating pathologies and apoptosis in several types of cancers. In addition to functioning as an enzyme, PLA2 can activate a phospholipase A2 receptor (PLA2R1) in plasma membrane. While the list of PLA2 targets extends to glucose homeostasis, intracellular energy balance, adipocyte development, and hepatic lipogenesis, the PLA2R1 downstream effectors are few and scarcely investigated. Among the most addressed PLA2R1 effects are regulation of pro-inflammatory signaling, autoimmunity, apoptosis, and senescence. Localized in glomeruli podocytes, the receptor can be identified by circulating anti-PLA2R1 autoantibodies leading to development of membranous nephropathy, a strong autoimmune inflammatory cascade. PLA2R1 was shown to induce activation of Janus-kinase 2 (JAK2) and estrogen-related receptor α (ERRα)-controlled mitochondrial proteins, as well as increasing the accumulation of reactive oxygen species, thus leading to apoptosis and senescence. These findings indicate the potential role of PLA2R1 as tumor suppressor. Epigenetic investigations addressed the role of DNA methylation, histone modifications, and specific microRNAs in the regulation of PLA2R1 expression. However, involvement of PLA2R1 in suppression of malignant growth and metastasis remains controversial. In this review, we summarize the recent findings that highlight the role of PLA2R1 in the regulation of carcinogenesis-related intracellular signaling.
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Affiliation(s)
- Olga Sukocheva
- School of Health Sciences, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia.
| | - Mario Menschikowski
- Institute of Clinical Chemistry and Laboratory Medicine, Carl Gustav Carus University Hospital, Technical University of Dresden, Fetscherstr. 74, D-01307 Dresden, Germany
| | - Albert Hagelgans
- Institute of Clinical Chemistry and Laboratory Medicine, Carl Gustav Carus University Hospital, Technical University of Dresden, Fetscherstr. 74, D-01307 Dresden, Germany
| | - Nagendra Sastry Yarla
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad 500 046, Telangana, India
| | - Gabriele Siegert
- Institute of Clinical Chemistry and Laboratory Medicine, Carl Gustav Carus University Hospital, Technical University of Dresden, Fetscherstr. 74, D-01307 Dresden, Germany
| | - Pallu Reddanna
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad 500 046, Telangana, India
| | - Anupam Bishayee
- Lake Erie College of Osteopathic Medicine, Bradenton, FL 34211, USA.
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13
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Duchez AC, Boudreau LH, Naika GS, Rousseau M, Cloutier N, Levesque T, Gelb MH, Boilard E. Respective contribution of cytosolic phospholipase A2α and secreted phospholipase A 2 IIA to inflammation and eicosanoid production in arthritis. Prostaglandins Other Lipid Mediat 2019; 143:106340. [PMID: 31129176 DOI: 10.1016/j.prostaglandins.2019.106340] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 05/11/2019] [Accepted: 05/15/2019] [Indexed: 12/30/2022]
Abstract
Phospholipase A2s (PLA2) play a key role in generation of eicosanoids. Cytosolic PLA2α (cPLA2α) is constitutively expressed in most cells, whereas IIA secreted PLA2 (sPLA2-IIA) is induced during inflammation and is present at high levels in the synovial fluid of rheumatoid arthritis patients. In mice, both cPLA2α and sPLA2-IIA have been implicated in autoimmune arthritis; however, the respective contribution of these two enzymes to the pathogenesis and production of eicosanoids is unknown. We evaluated the respective role of cPLA2α and sPLA2-IIA with regard to arthritis and eicosanoid profile in an in vivo model of arthritis. While arthritis was most severe in mice expressing both enzymes, it was abolished when both cPLA2α and sPLA2-IIA were lacking. cPLA2α played a dominant role in the severity of arthritis, although sPLA2-IIA sufficed to significantly contribute to the disease. Several eicosanoids were modulated during the course of arthritis and numerous species involved sPLA2-IIA expression. This study confirms the critical role of PLA2s in arthritis and unveils the distinct contribution of cPLA2α and sPLA2-IIA to the eicosanoid profile in arthritis.
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Affiliation(s)
- Anne-Claire Duchez
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Département de microbiologie et immunologie, Québec, QC, G1V 4G2, Canada
| | - Luc H Boudreau
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Département de microbiologie et immunologie, Québec, QC, G1V 4G2, Canada; Department of Chemistry and Biochemistry, Université de Moncton, Moncton, E1A 3E9, Canada
| | - Gajendra S Naika
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Matthieu Rousseau
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Département de microbiologie et immunologie, Québec, QC, G1V 4G2, Canada
| | - Nathalie Cloutier
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Département de microbiologie et immunologie, Québec, QC, G1V 4G2, Canada
| | - Tania Levesque
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Département de microbiologie et immunologie, Québec, QC, G1V 4G2, Canada
| | - Michael H Gelb
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Eric Boilard
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Département de microbiologie et immunologie, Québec, QC, G1V 4G2, Canada; Canadian National Transplantation Research Program, Edmonton, Alberta, Canada.
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14
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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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15
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Selectivity of phospholipid hydrolysis by phospholipase A 2 enzymes in activated cells leading to polyunsaturated fatty acid mobilization. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:772-783. [PMID: 30010011 DOI: 10.1016/j.bbalip.2018.07.002] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/08/2018] [Accepted: 07/10/2018] [Indexed: 12/14/2022]
Abstract
Phospholipase A2s are enzymes that hydrolyze the fatty acid at the sn-2 position of the glycerol backbone of membrane glycerophospholipids. Given the asymmetric distribution of fatty acids within phospholipids, where saturated fatty acids tend to be present at the sn-1 position, and polyunsaturated fatty acids such as those of the omega-3 and omega-6 series overwhelmingly localize in the sn-2 position, the phospholipase A2 reaction is of utmost importance as a regulatory checkpoint for the mobilization of these fatty acids and the subsequent synthesis of proinflammatory omega-6-derived eicosanoids on one hand, and omega-3-derived specialized pro-resolving mediators on the other. The great variety of phospholipase A2s, their differential substrate selectivity under a variety of pathophysiological conditions, as well as the different compartmentalization of each enzyme and accessibility to substrate, render this class of enzymes also key to membrane phospholipid remodeling reactions, and the generation of specific lipid mediators not related with canonical metabolites of omega-6 or omega-3 fatty acids. This review highlights novel findings regarding the selective hydrolysis of phospholipids by phospholipase A2s and the influence this may have on the ability of these enzymes to generate distinct lipid mediators with essential functions in biological processes. This brings a new understanding of the cellular roles of these enzymes depending upon activation conditions.
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16
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Boilard E. Extracellular vesicles and their content in bioactive lipid mediators: more than a sack of microRNA. J Lipid Res 2018; 59:2037-2046. [PMID: 29678959 DOI: 10.1194/jlr.r084640] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 03/26/2018] [Indexed: 01/08/2023] Open
Abstract
Extracellular vesicles (EVs), such as exosomes and microvesicles, are small membrane-bound vesicles released by cells under various conditions. In a multitude of physiological and pathological conditions, EVs contribute to intercellular communication by facilitating exchange of material between cells. Rapidly growing interest is aimed at better understanding EV function and their use as biomarkers. The vast EV cargo includes cytokines, growth factors, organelles, nucleic acids (messenger and micro RNA), and transcription factors. A large proportion of research dedicated to EVs is focused on their microRNA cargo; however, much less is known about other EV constituents, in particular, eicosanoids. These potent bioactive lipid mediators, derived from arachidonic acid, are shuttled in EVs along with the enzymes in charge of their synthesis. In the extracellular milieu, EVs also interact with secreted phospholipases to generate eicosanoids, which then regulate the transfer of cargo into a cellular recipient. Eicosanoids are useful as biomarkers and contribute to a variety of biological functions, including modulation of distal immune responses. Here, we review the reported roles of eicosanoids conveyed by EVs and describe their potential as biomarkers.
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Affiliation(s)
- Eric Boilard
- Centre de Recherche du CHU de Québec - Université Laval, Department of Infectious Diseases and Immunity, Quebec City, QC, Canada, and Canadian National Transplantation Research Program, Edmonton, AB, Canada
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17
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Abstract
Phospholipases are lipolytic enzymes that hydrolyze phospholipid substrates at specific ester bonds. Phospholipases are widespread in nature and play very diverse roles from aggression in snake venom to signal transduction, lipid mediator production, and metabolite digestion in humans. Phospholipases vary considerably in structure, function, regulation, and mode of action. Tremendous advances in understanding the structure and function of phospholipases have occurred in the last decades. This introductory chapter is aimed at providing a general framework of the current understanding of phospholipases and a discussion of their mechanisms of action and emerging biological functions.
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18
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Nolin JD, Lai Y, Ogden HL, Manicone AM, Murphy RC, An D, Frevert CW, Ghomashchi F, Naika GS, Gelb MH, Gauvreau GM, Piliponsky AM, Altemeier WA, Hallstrand TS. Secreted PLA2 group X orchestrates innate and adaptive immune responses to inhaled allergen. JCI Insight 2017; 2:94929. [PMID: 29093264 PMCID: PMC5752296 DOI: 10.1172/jci.insight.94929] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 09/26/2017] [Indexed: 01/15/2023] Open
Abstract
Phospholipase A2 (PLA2) enzymes regulate the formation of eicosanoids and lysophospholipids that contribute to allergic airway inflammation. Secreted PLA2 group X (sPLA2-X) was recently found to be increased in the airways of asthmatics and is highly expressed in airway epithelial cells and macrophages. In the current study, we show that allergen exposure increases sPLA2-X in humans and in mice, and that global deletion of Pla2g10 results in a marked reduction in airway hyperresponsiveness (AHR), eosinophil and T cell trafficking to the airways, airway occlusion, generation of type-2 cytokines by antigen-stimulated leukocytes, and antigen-specific immunoglobulins. Further, we found that Pla2g10-/- mice had reduced IL-33 levels in BALF, fewer type-2 innate lymphoid cells (ILC2s) in the lung, less IL-33-induced IL-13 expression in mast cells, and a marked reduction in both the number of newly recruited macrophages and the M2 polarization of these macrophages in the lung. These results indicate that sPLA2-X serves as a central regulator of both innate and adaptive immune response to proteolytic allergen.
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Affiliation(s)
- James D. Nolin
- Department of Medicine, Division of Pulmonary and Critical Care
| | - Ying Lai
- Department of Medicine, Division of Pulmonary and Critical Care
| | | | | | - Ryan C. Murphy
- Department of Medicine, Division of Pulmonary and Critical Care
| | - Dowon An
- Department of Medicine, Division of Pulmonary and Critical Care
| | - Charles W. Frevert
- Department of Medicine, Division of Pulmonary and Critical Care
- Department of Comparative Medicine
| | | | | | - Michael H. Gelb
- Department of Chemistry, and
- Department of Biochemistry, University of Washington, Seattle, Washington, USA
| | - Gail M. Gauvreau
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Adrian M. Piliponsky
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, USA
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19
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Hou S, Xu T, Xu J, Qu L, Xu Y, Chen L, Liu J. Structural basis for functional selectivity and ligand recognition revealed by crystal structures of human secreted phospholipase A 2 group IIE. Sci Rep 2017; 7:10815. [PMID: 28883454 PMCID: PMC5589937 DOI: 10.1038/s41598-017-11219-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 08/21/2017] [Indexed: 02/06/2023] Open
Abstract
Secreted phospholipases A2s (sPLA2s) are involved in various pathological conditions such as rheumatoid arthritis and cardiovascular disease. Many inhibitors were developed and studied in clinical trials, but none have reached the market yet. This failure may be attributed to the lack of subtype selectivity for these inhibitors. Therefore, more structural information for subtype sPLA2 is needed to guide the selective inhibitor development. In this study, the crystal structure of human sPLA2 Group IIE (hGIIE), coupled with mutagenesis experiments, proved that the flexible second calcium binding site and residue Asn21 in hGIIE are essential to its enzymatic activity. Five inhibitor bound hGIIE complex structures revealed the key residues (Asn21 and Gly6) of hGIIE that are responsible for interacting with inhibitors, and illustrated the difference in the inhibitor binding pocket with other sPLA2s. This will facilitate the structure-based design of sPLA2's selective inhibitors.
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Affiliation(s)
- Shulin Hou
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.,University of Chinese Academy of Sciences, Beijing, 100000, China
| | - Tingting Xu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.,School of Life Sciences, University of Science and Technology of China, Hefei, 230026, China
| | - Jinxin Xu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Linbing Qu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Yong Xu
- Guangdong Provincial Key Laboratory of Biocomputing, Institute of Chemical Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Ling Chen
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Jinsong Liu
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China. .,Guangdong Provincial Key Laboratory of Biocomputing, Institute of Chemical Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
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20
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Murakami M, Yamamoto K, Miki Y, Murase R, Sato H, Taketomi Y. The Roles of the Secreted Phospholipase A 2 Gene Family in Immunology. Adv Immunol 2016; 132:91-134. [PMID: 27769509 PMCID: PMC7112020 DOI: 10.1016/bs.ai.2016.05.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Within the phospholipase A2 (PLA2) family that hydrolyzes phospholipids to yield fatty acids and lysophospholipids, secreted PLA2 (sPLA2) enzymes comprise the largest group containing 11 isoforms in mammals. Individual sPLA2s exhibit unique tissue or cellular distributions and enzymatic properties, suggesting their distinct biological roles. Although PLA2 enzymes, particularly cytosolic PLA2 (cPLA2α), have long been implicated in inflammation by driving arachidonic acid metabolism, the precise biological roles of sPLA2s have remained a mystery over the last few decades. Recent studies employing mice gene-manipulated for individual sPLA2s, in combination with mass spectrometric lipidomics to identify their target substrates and products in vivo, have revealed their roles in diverse biological events, including immunity and associated disorders, through lipid mediator-dependent or -independent processes in given microenvironments. In this review, we summarize our current knowledge of the roles of sPLA2s in various immune responses and associated diseases.
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Affiliation(s)
- M Murakami
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Tokyo, Japan.
| | - K Yamamoto
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan; Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Y Miki
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - R Murase
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - H Sato
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Y Taketomi
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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21
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Murase R, Sato H, Yamamoto K, Ushida A, Nishito Y, Ikeda K, Kobayashi T, Yamamoto T, Taketomi Y, Murakami M. Group X Secreted Phospholipase A2 Releases ω3 Polyunsaturated Fatty Acids, Suppresses Colitis, and Promotes Sperm Fertility. J Biol Chem 2016; 291:6895-911. [PMID: 26828067 DOI: 10.1074/jbc.m116.715672] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Indexed: 12/31/2022] Open
Abstract
Within the secreted phospholipase A2(sPLA2) family, group X sPLA2(sPLA2-X) has the highest capacity to hydrolyze cellular membranes and has long been thought to promote inflammation by releasing arachidonic acid, a precursor of pro-inflammatory eicosanoids. Unexpectedly, we found that transgenic mice globally overexpressing human sPLA2-X (PLA2G10-Tg) displayed striking immunosuppressive and lean phenotypes with lymphopenia and increased M2-like macrophages, accompanied by marked elevation of free ω3 polyunsaturated fatty acids (PUFAs) and their metabolites. Studies usingPla2g10-deficient mice revealed that endogenous sPLA2-X, which is highly expressed in the colon epithelium and spermatozoa, mobilized ω3 PUFAs or their metabolites to protect against dextran sulfate-induced colitis and to promote fertilization, respectively. In colitis, sPLA2-X deficiency increased colorectal expression of Th17 cytokines, and ω3 PUFAs attenuated their production by lamina propria cells partly through the fatty acid receptor GPR120. In comparison, cytosolic phospholipase A2(cPLA2α) protects from colitis by mobilizing ω6 arachidonic acid metabolites, including prostaglandin E2 Thus, our results underscore a previously unrecognized role of sPLA2-X as an ω3 PUFA mobilizerin vivo, segregated mobilization of ω3 and ω6 PUFA metabolites by sPLA2-X and cPLA2α, respectively, in protection against colitis, and the novel role of a particular sPLA2-X-driven PUFA in fertilization.
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Affiliation(s)
- Remi Murase
- From the Lipid Metabolism Project and School of Pharmacy, Showa University, Tokyo 142-8555, Japan
| | | | | | - Ayako Ushida
- From the Lipid Metabolism Project and Department of Biology, Faculty of Science, Ochanomizu University, Tokyo 112-8610, Japan
| | - Yasumasa Nishito
- Core Technology and Research Center, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kazutaka Ikeda
- Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan, and
| | - Tetsuyuki Kobayashi
- Department of Biology, Faculty of Science, Ochanomizu University, Tokyo 112-8610, Japan
| | | | | | - Makoto Murakami
- From the Lipid Metabolism Project and AMED-CREST, Japan Agency for Medical Research and Development, Tokyo 100-0004, Japan
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22
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Tanabe T, Shimokawaji T, Kanoh S, Rubin BK. Secretory phospholipases A2 are secreted from ciliated cells and increase mucin and eicosanoid secretion from goblet cells. Chest 2015; 147:1599-1609. [PMID: 25429648 DOI: 10.1378/chest.14-0258] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Secretory phospholipases A2 (sPLA2) initiate the biosynthesis of eicosanoids, are increased in the airways of people with severe asthma, and induce mucin hypersecretion. We used IL-13-transformed, highly enriched goblet cells and differentiated (ciliary cell-enriched) human bronchial epithelial cell culture to evaluate the relative contribution of ciliated and goblet cells to airway sPLA2 generation and response. We wished to determine the primary source(s) of sPLA2 and leukotrienes in human airway epithelial cells. METHODS Human bronchial epithelial cells from subjects without lung disease were differentiated to a ciliated-enriched or goblet-enriched cell phenotype. Synthesis of sPLA2, cysteinyl leukotrienes (cysLTs), and airway mucin messenger RNA and protein was measured by real-time-polymerase chain reaction and an enzyme-linked immunosorbent assay, and the localization of mucin and sPLA2 to specific cells types was confirmed by confocal microscopy. RESULTS sPLA2 group IIa, V, and X messenger RNA expression was increased in ciliated-enriched cells (P < .001) but not in goblet-enriched cells. sPLA2 were secreted from the apical (air) side of ciliated-enriched cells but not goblet-enriched cells (P < .001). Immunostaining of sPLA2 V was strongly positive in ciliated-enriched cells but not in goblet-enriched cells. sPLA2 released cysLTs from goblet-enriched cells but not from ciliated-enriched cells, and this result was greatest with sPLA2 V (P < .05). sPLA2 V increased goblet-enriched cell mucin secretion, which was inhibited by inhibitors of lipoxygenase or cyclooxygenase (P < .02). CONCLUSIONS sPLA2 are secreted from ciliated cells and appear to induce mucin and cysLT secretion from goblet cells, strongly suggesting that airway goblet cells are proinflammatory effector cells.
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Affiliation(s)
- Tsuyoshi Tanabe
- Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA.
| | - Tadasuke Shimokawaji
- Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA
| | - Soichiro Kanoh
- Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA
| | - Bruce K Rubin
- Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA
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23
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Rousseau M, Naika GS, Perron J, Jacques F, Gelb MH, Boilard E. Study of the role of cytosolic phospholipase A2 alpha in eicosanoid generation and thymocyte maturation in the thymus. PLoS One 2015; 10:e0126204. [PMID: 25969996 PMCID: PMC4430275 DOI: 10.1371/journal.pone.0126204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 03/30/2015] [Indexed: 11/29/2022] Open
Abstract
The thymus is a primary lymphoid organ, home of maturation and selection of thymocytes for generation of functional T-cells. Multiple factors are involved throughout the different stages of the maturation process to tightly regulate T-cell production. The metabolism of arachidonic acid by cyclooxygenases, lipoxygenases and specific isomerases generates eicosanoids, lipid mediators capable of triggering cellular responses. In this study, we determined the profile of expression of the eicosanoids present in the mouse thymus at different stages of thymocyte development. As the group IVA cytosolic phospholipase A2 (cPLA2α) catalyzes the hydrolysis of phospholipids, thereby generating arachidonic acid, we further verified its contribution by including cPLA2α deficient mice to our investigations. We found that a vast array of eicosanoids is expressed in the thymus, which expression is substantially modulated through thymocyte development. The cPLA2α was dispensable in the generation of most eicosanoids in the thymus and consistently, the ablation of the cPLA2α gene in mouse thymus and the culture of thymuses from human newborns in presence of the cPLA2α inhibitor pyrrophenone did not impact thymocyte maturation. This study provides information on the eicosanoid repertoire present during thymocyte development and suggests that thymocyte maturation can occur independently of cPLA2α.
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Affiliation(s)
- Matthieu Rousseau
- Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l’Université Laval, Québec, QC, Canada
| | - Gajendra S. Naika
- Department of Chemistry, University of Washington, Seattle, WA, the United States of America
| | - Jean Perron
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l’Université Laval, Québec, QC, Canada
| | - Frederic Jacques
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l’Université Laval, Québec, QC, Canada
| | - Michael H. Gelb
- Department of Chemistry, University of Washington, Seattle, WA, the United States of America
| | - Eric Boilard
- Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l’Université Laval, Québec, QC, Canada
- * E-mail:
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Murakami M, Sato H, Miki Y, Yamamoto K, Taketomi Y. A new era of secreted phospholipase A₂. J Lipid Res 2015; 56:1248-61. [PMID: 25805806 DOI: 10.1194/jlr.r058123] [Citation(s) in RCA: 161] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Indexed: 12/18/2022] Open
Abstract
Among more than 30 members of the phospholipase A2 (PLA2) superfamily, secreted PLA2 (sPLA2) enzymes represent the largest family, being Ca(2+)-dependent low-molecular-weight enzymes with a His-Asp catalytic dyad. Individual sPLA2s exhibit unique tissue and cellular distributions and enzymatic properties, suggesting their distinct biological roles. Recent studies using transgenic and knockout mice for nearly a full set of sPLA2 subtypes, in combination with sophisticated lipidomics as well as biochemical and cell biological studies, have revealed distinct contributions of individual sPLA2s to various pathophysiological events, including production of pro- and anti-inflammatory lipid mediators, regulation of membrane remodeling, degradation of foreign phospholipids in microbes or food, or modification of extracellular noncellular lipid components. In this review, we highlight the current understanding of the in vivo functions of sPLA2s and the underlying lipid pathways as revealed by a series of studies over the last decade.
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Affiliation(s)
- Makoto Murakami
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan CREST, Japan Science and Technology Agency, Saitama 332-0012, Japan
| | - Hiroyasu Sato
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Yoshimi Miki
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kei Yamamoto
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Yoshitaka Taketomi
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
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Rousseau M, Belleannee C, Duchez AC, Cloutier N, Levesque T, Jacques F, Perron J, Nigrovic PA, Dieude M, Hebert MJ, Gelb MH, Boilard E. Detection and quantification of microparticles from different cellular lineages using flow cytometry. Evaluation of the impact of secreted phospholipase A2 on microparticle assessment. PLoS One 2015; 10:e0116812. [PMID: 25587983 PMCID: PMC4294685 DOI: 10.1371/journal.pone.0116812] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Accepted: 12/15/2014] [Indexed: 11/20/2022] Open
Abstract
Microparticles, also called microvesicles, are submicron extracellular vesicles produced by plasma membrane budding and shedding recognized as key actors in numerous physio(patho)logical processes. Since they can be released by virtually any cell lineages and are retrieved in biological fluids, microparticles appear as potent biomarkers. However, the small dimensions of microparticles and soluble factors present in body fluids can considerably impede their quantification. Here, flow cytometry with improved methodology for microparticle resolution was used to detect microparticles of human and mouse species generated from platelets, red blood cells, endothelial cells, apoptotic thymocytes and cells from the male reproductive tract. A family of soluble proteins, the secreted phospholipases A2 (sPLA2), comprises enzymes concomitantly expressed with microparticles in biological fluids and that catalyze the hydrolysis of membrane phospholipids. As sPLA2 can hydrolyze phosphatidylserine, a phospholipid frequently used to assess microparticles, and might even clear microparticles, we further considered the impact of relevant sPLA2 enzymes, sPLA2 group IIA, V and X, on microparticle quantification. We observed that if enriched in fluids, certain sPLA2 enzymes impair the quantification of microparticles depending on the species studied, the source of microparticles and the means of detection employed (surface phosphatidylserine or protein antigen detection). This study provides analytical considerations for appropriate interpretation of microparticle cytofluorometric measurements in biological samples containing sPLA2 enzymes.
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Affiliation(s)
- Matthieu Rousseau
- Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l’Université Laval, Québec, QC, Canada
| | - Clemence Belleannee
- Centre de Recherche du CHUQ and Département d’Obstétrique-Gynécologie, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Anne-Claire Duchez
- Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l’Université Laval, Québec, QC, Canada
| | - Nathalie Cloutier
- Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l’Université Laval, Québec, QC, Canada
| | - Tania Levesque
- Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l’Université Laval, Québec, QC, Canada
| | | | - Jean Perron
- Centre Hospitalier Universitaire de Québec, Québec, Canada
| | - Peter A. Nigrovic
- Division of Rheumatology, Immunology and Allergy, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States of America
- Division of Immunology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, United States of America
| | - Melanie Dieude
- Centre hospitalier de l’Université de Montréal (CRCHUM), Montréal, QC, Canada
| | - Marie-Josee Hebert
- Centre hospitalier de l’Université de Montréal (CRCHUM), Montréal, QC, Canada
| | - Michael H. Gelb
- Department of Chemistry, University of Washington, Seattle, WA, United States of America
| | - Eric Boilard
- Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l’Université Laval, Québec, QC, Canada
- * E-mail:
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Guan W, Steffen BT, Lemaitre RN, Wu JH, Tanaka T, Manichaikul A, Foy M, Rich SS, Wang L, Nettleton JA, Tang W, Gu X, Bandinelli S, King IB, McKnight B, Psaty BM, Siscovick D, Djousse L, Chen YDI, Ferrucci L, Fornage M, Mozafarrian D, Tsai MY, Steffen LM. Genome-wide association study of plasma N6 polyunsaturated fatty acids within the cohorts for heart and aging research in genomic epidemiology consortium. CIRCULATION. CARDIOVASCULAR GENETICS 2014; 7:321-331. [PMID: 24823311 PMCID: PMC4123862 DOI: 10.1161/circgenetics.113.000208] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Omega6 (n6) polyunsaturated fatty acids (PUFAs) and their metabolites are involved in cell signaling, inflammation, clot formation, and other crucial biological processes. Genetic components, such as variants of fatty acid desaturase (FADS) genes, determine the composition of n6 PUFAs. METHODS AND RESULTS To elucidate undiscovered biological pathways that may influence n6 PUFA composition, we conducted genome-wide association studies and meta-analyses of associations of common genetic variants with 6 plasma n6 PUFAs in 8631 white adults (55% women) across 5 prospective studies. Plasma phospholipid or total plasma fatty acids were analyzed by similar gas chromatography techniques. The n6 fatty acids linoleic acid (LA), γ-linolenic acid (GLA), dihomo-GLA, arachidonic acid, and adrenic acid were expressed as percentage of total fatty acids. We performed linear regression with robust SEs to test for single-nucleotide polymorphism-fatty acid associations, with pooling using inverse-variance-weighted meta-analysis. Novel regions were identified on chromosome 10 associated with LA (rs10740118; P=8.1×10(-9); near NRBF2), on chromosome 16 with LA, GLA, dihomo-GLA, and arachidonic acid (rs16966952; P=1.2×10(-15), 5.0×10(-11), 7.6×10(-65), and 2.4×10(-10), respectively; NTAN1), and on chromosome 6 with adrenic acid after adjustment for arachidonic acid (rs3134950; P=2.1×10(-10); AGPAT1). We confirmed previous findings of the FADS cluster on chromosome 11 with LA and arachidonic acid, and further observed novel genome-wide significant association of this cluster with GLA, dihomo-GLA, and adrenic acid (P=2.3×10(-72), 2.6×10(-151), and 6.3×10(-140), respectively). CONCLUSIONS Our findings suggest that along with the FADS gene cluster, additional genes may influence n6 PUFA composition.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Aging/blood
- Aging/genetics
- Chromosomes, Human, Pair 10/genetics
- Chromosomes, Human, Pair 16/genetics
- Chromosomes, Human, Pair 6/genetics
- Fatty Acid Desaturases/genetics
- Fatty Acids, Omega-6/blood
- Female
- Genome-Wide Association Study
- Genomics
- Heart Diseases/blood
- Heart Diseases/epidemiology
- Heart Diseases/genetics
- Humans
- Male
- Middle Aged
- Polymorphism, Single Nucleotide
- Prospective Studies
- Sequence Analysis, DNA
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Affiliation(s)
- Weihua Guan
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN
| | - Brian T. Steffen
- Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN
| | - Rozenn N. Lemaitre
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA
| | - Jason H.Y. Wu
- Department of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA
- School of Medicine and Pharmacology, University of Western Australia, Perth, Australia
| | - Toshiko Tanaka
- Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD
| | - Ani Manichaikul
- Center for Public Health Genomics, Division of Biostatistics and Epidemiology, University of Virginia, Charlottesville, VA
| | - Millennia Foy
- Institute of Molecular Medicine, University of Texas Health Sciences Center in Houston, Houston, TX
| | - Stephen S. Rich
- Center for Public Health Genomics, Division of Biostatistics and Epidemiology, University of Virginia, Charlottesville, VA
| | - Lu Wang
- Department of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA
| | - Jennifer A. Nettleton
- Department of Epidemiology, University of Texas Health Sciences Center in Houston, Houston, TX
| | - Weihong Tang
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN
| | - Xiangjun Gu
- Institute of Molecular Medicine, University of Texas Health Sciences Center in Houston, Houston, TX
| | - Stafania Bandinelli
- Geriatric Rehabilitation Unit, Azienda Sanitaria Firenze (ASF), Florence, Italy
| | - Irena B. King
- Department of Internal Medicine, University of New Mexico, Albuquerque, New Mexico
| | - Barbara McKnight
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA
| | - Bruce M. Psaty
- Cardiovascular Health Research Unit, Departments of Medicine, Epidemiology and Health Services, University of Washington, Seattle, WA
- Group Health Research Institute, Group Health Cooperative, Seattle, WA
| | - David Siscovick
- Cardiovascular Health Research Unit, Departments of Medicine, Epidemiology and Health Services, University of Washington, Seattle, WA
| | - Luc Djousse
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School & Boston VA Healthcare System, Boston, MA
| | | | - Luigi Ferrucci
- Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD
| | - Myriam Fornage
- Institute of Molecular Medicine, University of Texas Health Sciences Center in Houston, Houston, TX
- Department of Epidemiology, University of Texas Health Sciences Center in Houston, Houston, TX
| | - Dariush Mozafarrian
- Division of Cardiovascular Medicine, Brigham and Women's Hospital and Harvard Medical School; Department of Epidemiology, Harvard School of Public Health, Boston, MA
| | - Michael Y. Tsai
- Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN
| | - Lyn M. Steffen
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN
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Pucer A, Brglez V, Payré C, Pungerčar J, Lambeau G, Petan T. Group X secreted phospholipase A(2) induces lipid droplet formation and prolongs breast cancer cell survival. Mol Cancer 2013; 12:111. [PMID: 24070020 PMCID: PMC3852912 DOI: 10.1186/1476-4598-12-111] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 09/24/2013] [Indexed: 01/08/2023] Open
Abstract
Background Alterations in lipid metabolism are inherent to the metabolic transformations that support tumorigenesis. The relationship between the synthesis, storage and use of lipids and their importance in cancer is poorly understood. The human group X secreted phospholipase A2 (hGX sPLA2) releases fatty acids (FAs) from cell membranes and lipoproteins, but its involvement in the regulation of cellular FA metabolism and cancer is not known. Results Here we demonstrate that hGX sPLA2 induces lipid droplet (LD) formation in invasive breast cancer cells, stimulates their proliferation and prevents their death on serum deprivation. The effects of hGX sPLA2 are shown to be dependent on its enzymatic activity, are mimicked by oleic acid and include activation of protein kinase B/Akt, a cell survival signaling kinase. The hGX sPLA2-stimulated LD biogenesis is accompanied by AMP-activated protein kinase (AMPK) activation, up-regulation of FA oxidation enzymes and the LD-coating protein perilipin 2, and suppression of lipogenic gene expression. Prolonged activation of AMPK inhibited hGX sPLA2-induced LD formation, while etomoxir, an inhibitor of FA oxidation, abrogated both LD formation and cell survival. The hGX sPLA2-induced changes in lipid metabolism provide a minimal immediate proliferative advantage during growth under optimal conditions, but they confer to the breast cancer cells a sustained ability to resist apoptosis during nutrient and growth factor limitation. Conclusion Our results identify hGX sPLA2 as a novel modulator of lipid metabolism that promotes breast cancer cell growth and survival by stimulating LD formation and FA oxidation.
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Affiliation(s)
- Anja Pucer
- Department of Molecular and Biomedical Sciences, JoŽef Stefan Institute, Ljubljana, Slovenia.
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Hsieh FH. Additional insights into epithelial secreted phospholipase A2 group X in asthma. Am J Respir Crit Care Med 2013; 188:2-3. [PMID: 23815713 DOI: 10.1164/rccm.201304-0792ed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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RHEE HAEJIN, JI LITING, KIM SEUNGHYUK, LEE JONGHO. Human group V secretory phospholipase A2 is associated with lipid rafts and internalized in a flotillin-dependent pathway. Int J Mol Med 2013; 32:1126-36. [DOI: 10.3892/ijmm.2013.1492] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 08/23/2013] [Indexed: 11/06/2022] Open
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Chen S, Subbaiah PV. Regioisomers of Phosphatidylcholine Containing DHA and Their Potential to Deliver DHA to the Brain: Role of Phospholipase Specificities. Lipids 2013; 48:675-86. [DOI: 10.1007/s11745-013-3791-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 04/02/2013] [Indexed: 01/08/2023]
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31
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Kuo JH, Chen YP, Liu JS, Dubrac A, Quemener C, Prats H, Bikfalvi A, Wu WG, Sue SC. Alternative C-terminal helix orientation alters chemokine function: structure of the anti-angiogenic chemokine, CXCL4L1. J Biol Chem 2013; 288:13522-33. [PMID: 23536183 DOI: 10.1074/jbc.m113.455329] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND CXCL4L1 is a highly potent anti-angiogenic and anti-tumor chemokine, and its structural information is unknown. RESULTS CXCL4L1 x-ray structure is determined, and it reveals a previously unrecognized chemokine structure adopting a novel C-terminal helix conformation. CONCLUSION The alternative helix conformation enhances the anti-angiogenic activity of CXCL4L1 by reducing the glycosaminoglycan binding ability. SIGNIFICANCE Chemokine C-terminal helix orientation is critical in regulating their functions. Chemokines, a subfamily of cytokines, are small, secreted proteins that mediate a variety of biological processes. Various chemokines adopt remarkable conserved tertiary structure comprising an anti-parallel β-sheet core domain followed by a C-terminal helix that packs onto the β-sheet. The conserved structural feature has been considered critical for chemokine function, including binding to cell surface receptor. The recently isolated variant, CXCL4L1, is a homologue of CXCL4 chemokine (or platelet factor 4) with potent anti-angiogenic activity and differed only in three amino acid residues of P58L, K66E, and L67H. In this study we show by x-ray structural determination that CXCL4L1 adopts a previously unrecognized structure at its C terminus. The orientation of the C-terminal helix protrudes into the aqueous space to expose the entire helix. The alternative helix orientation modifies the overall chemokine shape and surface properties. The L67H mutation is mainly responsible for the swing-out effect of the helix, whereas mutations of P58L and K66E only act secondarily. This is the first observation that reports an open conformation of the C-terminal helix in a chemokine. This change leads to a decrease of its glycosaminoglycan binding properties and to an enhancement of its anti-angiogenic and anti-tumor effects. This unique structure is recent in evolution and has allowed CXCL4L1 to gain novel functional properties.
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Affiliation(s)
- Je-Hung Kuo
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu 30013, Taiwan
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Phospholipases of mineralization competent cells and matrix vesicles: roles in physiological and pathological mineralizations. Int J Mol Sci 2013; 14:5036-129. [PMID: 23455471 PMCID: PMC3634480 DOI: 10.3390/ijms14035036] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/24/2013] [Accepted: 01/25/2013] [Indexed: 02/08/2023] Open
Abstract
The present review aims to systematically and critically analyze the current knowledge on phospholipases and their role in physiological and pathological mineralization undertaken by mineralization competent cells. Cellular lipid metabolism plays an important role in biological mineralization. The physiological mechanisms of mineralization are likely to take place in tissues other than in bones and teeth under specific pathological conditions. For instance, vascular calcification in arteries of patients with renal failure, diabetes mellitus or atherosclerosis recapitulates the mechanisms of bone formation. Osteoporosis—a bone resorbing disease—and rheumatoid arthritis originating from the inflammation in the synovium are also affected by cellular lipid metabolism. The focus is on the lipid metabolism due to the effects of dietary lipids on bone health. These and other phenomena indicate that phospholipases may participate in bone remodelling as evidenced by their expression in smooth muscle cells, in bone forming osteoblasts, chondrocytes and in bone resorbing osteoclasts. Among various enzymes involved, phospholipases A1 or A2, phospholipase C, phospholipase D, autotaxin and sphingomyelinase are engaged in membrane lipid remodelling during early stages of mineralization and cell maturation in mineralization-competent cells. Numerous experimental evidences suggested that phospholipases exert their action at various stages of mineralization by affecting intracellular signaling and cell differentiation. The lipid metabolites—such as arachidonic acid, lysophospholipids, and sphingosine-1-phosphate are involved in cell signaling and inflammation reactions. Phospholipases are also important members of the cellular machinery engaged in matrix vesicle (MV) biogenesis and exocytosis. They may favour mineral formation inside MVs, may catalyse MV membrane breakdown necessary for the release of mineral deposits into extracellular matrix (ECM), or participate in hydrolysis of ECM. The biological functions of phospholipases are discussed from the perspective of animal and cellular knockout models, as well as disease implications, development of potent inhibitors and therapeutic interventions.
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Ammodytoxins efficiently release arachidonic acid and induce apoptosis in a motoneuronal cell line in an enzymatic activity-dependent manner. Neurotoxicology 2012; 35:91-100. [PMID: 23266427 DOI: 10.1016/j.neuro.2012.12.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 12/14/2012] [Accepted: 12/14/2012] [Indexed: 11/20/2022]
Abstract
Secreted phospholipases A2 (sPLA2s) are phospholipolytic enzymes and receptor ligands whose action affects cell death and survival. We have previously shown that ammodytoxin A (AtxA), a snake venom sPLA2, is rapidly internalized into motoneuronal NSC34 cells, inducing characteristic neurotoxic sPLA2 cell damage and apoptosis. In this study, we have analyzed the role of sPLA2 enzymatic activity, including arachidonic acid (AA) release, in the induction of motoneuronal apoptosis by AtxA and homologous recombinant sPLA2s with different enzymatic properties: an AtxA mutant (V31W) with very high enzymatic activity, enzymatically inactive S49-sPLA2 (ammodytin L, AtnL), its mutant (LW) with restored enzymatic activity, and non-toxic, enzymatically active sPLA2 (AtnI2). Addition of AA, AtxA, AtxA-V31W and AtnL-LW, but not AtnL and AtnI2, to NSC34 cells resulted in caspase-3 activation, DNA fragmentation and disruption of mitochondrial membrane potential, leading to a significant and rapid decrease in motoneuronal cell viability that was not observed in C2C12 myoblasts and HEK293 cells. AtxA, AtxA-V31W and AtnL-LW, but not AtnL and AtnI2, also liberated large amounts of AA specifically from motoneuronal cells, and this ability correlated well with the ability to induce apoptotic changes and decrease cell viability. The enzymatic activity of AtxA and similar sPLA2s is thus necessary, but not sufficient, for inducing motoneuronal apoptosis. This suggests that specific binding to the motoneuronal cell surface, followed by internalization and enzymatic activity-dependent induction of apoptosis, possibly as a consequence of extensive extra- and intracellular AA release, is necessary for Atx-induced motoneuronal cell death.
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Perrin-Cocon L, Diaz O, André P, Lotteau V. Modified lipoproteins provide lipids that modulate dendritic cell immune function. Biochimie 2012; 95:103-8. [PMID: 22959067 DOI: 10.1016/j.biochi.2012.08.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 08/09/2012] [Indexed: 12/19/2022]
Abstract
Both physiological and pathological situations can result in biochemical changes of low-density lipoproteins (LDL). Because they can deliver signals to dendritic cells (DC), these modified lipoproteins now appear as regulators of the immune response. Among these modified lipoproteins, oxidized LDL (oxLDL) that accumulate during inflammatory conditions have been extensively studied. Numerous studies have shown that oxLDL induce the maturation of DC, enhancing their ability to activate IFNγ secretion by T cells. LDL treated by secreted phospholipase A(2) also promote DC maturation. Among the bioactive lipids generated by oxidation or phospholipase treatment of LDL, lysophosphatidylcholine (LPC) and some saturated fatty acids induce DC maturation whereas some unsaturated fatty acids or oxidized derivatives have opposite effects. Among other factors, the nuclear receptor peroxisome-proliferator activated receptor γ (PPARγ) plays a crucial role in this regulation. Non-modified lipoproteins also contribute to the regulation of DC function, suggesting that the balance between native and modified lipoproteins, as well as the biochemical nature of the LDL modifications, can regulate the activation threshold of DC. Here we discuss two pathological situations in which the impact of LDL modifications on inflammation and immunity could play an important role. During atherosclerosis, modified LDL accumulating in the arterial intima may interfere with DC maturation and function, promoting a Th1 immune response and a local inflammation favoring the development of the pathology. In patients chronically infected, the hepatitis C virus (HCV) interferes with lipoprotein metabolism resulting in the production of infectious modified lipoproteins. These lipo-viral-particles (LVP) are modified low-density lipoproteins containing viral material that can alter DC maturation and affect specific toll-like receptor signaling. In conclusion, lipoprotein modifications play an important role in the regulation of immunity by delivering signals of danger to DC and modulating their function.
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Mattiazzi M, Sun Y, Wolinski H, Bavdek A, Petan T, Anderluh G, Kohlwein SD, Drubin DG, Križaj I, Petrovič U. A neurotoxic phospholipase A2 impairs yeast amphiphysin activity and reduces endocytosis. PLoS One 2012; 7:e40931. [PMID: 22844417 PMCID: PMC3402474 DOI: 10.1371/journal.pone.0040931] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Accepted: 06/15/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Presynaptically neurotoxic phospholipases A(2) inhibit synaptic vesicle recycling through endocytosis. PRINCIPAL FINDINGS Here we provide insight into the action of a presynaptically neurotoxic phospholipase A(2) ammodytoxin A (AtxA) on clathrin-dependent endocytosis in budding yeast. AtxA caused changes in the dynamics of vesicle formation and scission from the plasma membrane in a phospholipase activity dependent manner. Our data, based on synthetic dosage lethality screen and the analysis of the dynamics of sites of endocytosis, indicate that AtxA impairs the activity of amphiphysin. CONCLUSIONS We identified amphiphysin and endocytosis as the target of AtxA intracellular activity. We propose that AtxA reduces endocytosis following a mechanism of action which includes both a specific protein-protein interaction and enzymatic activity, and which is applicable to yeast and mammalian cells. Knowing how neurotoxic phospholipases A(2) work can open new ways to regulate endocytosis.
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Affiliation(s)
- Mojca Mattiazzi
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Yidi Sun
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Heimo Wolinski
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Andrej Bavdek
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Toni Petan
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Gregor Anderluh
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Sepp D. Kohlwein
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - David G. Drubin
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Igor Križaj
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Uroš Petrovič
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
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Differences between group X and group V secretory phospholipase A(2) in lipolytic modification of lipoproteins. Cell Mol Biol Lett 2012; 17:459-78. [PMID: 22706677 PMCID: PMC6275602 DOI: 10.2478/s11658-012-0019-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 05/31/2012] [Indexed: 11/20/2022] Open
Abstract
Secretory phospholipases A(2) (sPLA(2)s) are a diverse family of low molecular mass enzymes (13-18 kDa) that hydrolyze the sn-2 fatty acid ester bond of glycerophospholipids to produce free fatty acids and lysophospholipids. We have previously shown that group X sPLA(2) (sPLA(2)-X) had a strong hydrolyzing activity toward phosphatidylcholine in low-density lipoprotein (LDL) linked to the formation of lipid droplets in the cytoplasm of macrophages. Here, we show that group V sPLA(2) (sPLA(2)-V) can also cause the lipolysis of LDL, but its action differs remarkably from that of sPLA(2)-X in several respects. Although sPLA(2)-V released almost the same amount of fatty acids from LDL, it released more linoleic acid and less arachidonic acid than sPLA(2)-X. In addition, the requirement of Ca(2+) for the lipolysis of LDL was about 10-fold higher for sPLA(2)-V than sPLA(2)-X. In fact, the release of fatty acids from human serum was hardly detectable upon incubation with sPLA(2)-V in the presence of sodium citrate, which contrasted with the potent response to sPLA(2)-X. Moreover, sPLA(2)-X, but not sPLA(2)-V, was found to specifically interact with LDL among the serum proteins, as assessed by gel-filtration chromatography as well as sandwich enzyme-immunosorbent assay using anti-sPLA(2)-X and anti-apoB antibodies. Surface plasmon resonance studies have revealed that sPLA2-X can bind to LDL with high-affinity (K(d) = 3.1 nM) in the presence of Ca(2+). Selective interaction of sPLA(2)-X with LDL might be involved in the efficient hydrolysis of cell surface or intracellular phospholipids during foam cell formation.
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Atout R, Karabina SA, Dollet S, Carreras M, Payré C, André P, Lambeau G, Lotteau V, Ninio E, Perrin-Cocon L. Human group X secreted phospholipase A2 induces dendritic cell maturation through lipoprotein-dependent and -independent mechanisms. Atherosclerosis 2012; 222:367-74. [DOI: 10.1016/j.atherosclerosis.2012.03.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 01/25/2012] [Accepted: 03/13/2012] [Indexed: 10/28/2022]
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Nelson J, Francom LL, Anderson L, Damm K, Baker R, Chen J, Franklin S, Hamaker A, Izidoro I, Moss E, Orton M, Stevens E, Yeung C, Judd AM, Bell JD. Investigation into the role of phosphatidylserine in modifying the susceptibility of human lymphocytes to secretory phospholipase A(2) using cells deficient in the expression of scramblase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:1196-204. [PMID: 22266334 DOI: 10.1016/j.bbamem.2012.01.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 11/22/2011] [Accepted: 01/09/2012] [Indexed: 12/12/2022]
Abstract
Normal human lymphocytes resisted the hydrolytic action of secretory phospholipase A(2) but became susceptible to the enzyme following treatment with a calcium ionophore, ionomycin. To test the hypothesis that this susceptibility requires exposure of the anionic lipid phosphatidylserine on the external face of the cell membrane, experiments were repeated with a human Burkitt's lymphoma cell line (Raji cells). In contrast to normal lymphocytes or S49 mouse lymphoma cells, most of the Raji cells (83%) did not translocate phosphatidylserine to the cell surface upon treatment with ionomycin. Those few that did display exposed phosphatidylserine were hydrolyzed immediately upon addition of phospholipase A(2). Interestingly, the remaining cells were also completely susceptible to the enzyme but were hydrolyzed at a slower rate and after a latency of about 100s. In contradistinction to the defect in phosphatidylserine translocation, Raji cells did display other physical membrane changes upon ionomycin treatment that may be relevant to hydrolysis by phospholipase A(2). These changes were detected by merocyanine 540 and trimethylammonium diphenylhexatriene fluorescence and were common among normal lymphocytes, S49 cells, and Raji cells. The levels of these latter effects corresponded well with the relative rates of hydrolysis among the three cell lines. These results suggested that while phosphatidylserine enhances the rate of cell membrane hydrolysis by secretory phospholipase A(2), it is not an absolute requirement. Other physical properties such as membrane order contribute to the level of membrane susceptibility to the enzyme independent of phosphatidylserine.
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Affiliation(s)
- Jennifer Nelson
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, Utah 84602, USA
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Karray A, Gargouri Y, Verger R, Bezzine S. Phospholipase A2 purification and characterization: a case study. Methods Mol Biol 2012; 861:283-297. [PMID: 22426725 DOI: 10.1007/978-1-61779-600-5_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We compared here the purification procedures, the pH, the calcium, the bile salts, and the temperature dependencies as well as the catalytic activities on phosphatidylcholine (PC) and phosphatidylethanolamine (PE) of two purified secreted PLA2 from chicken pancreatic (ChPLA2-IB) and chicken intestinal (ChPLA2-IIA) origins. Interestingly, ChPLA2-IB hydrolyzes efficiently both purified PC and PE, whereas ChPLA2-IIA hydrolyzes only PE and not PC, even after a long incubation period. These analytical results clearly indicate that the catalytic activity of ChPLA2-IIA, measured with the pH-stat and using egg yolk as substrate, is mainly due to the hydrolysis of the PE fraction present in egg yolk.
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Affiliation(s)
- Aida Karray
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, Ecole Nationale d'Ingénieurs de Sfax, Sfax, Tunisia
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Abstract
Phospholipids are present in all living organisms. They are a major component of all biological membranes, along with glycolipids and cholesterol. Enzymes aimed at cleaving the various bonds in phospholipids, namely phospholipases, are consequently widespread in nature, playing very diverse roles from aggression in snake venom to signal transduction, lipid mediators production, and digestion in humans. Although all phospholipases target phospholipids as substrates, they vary in the site of action on the phospholipids molecules, physiological function, mode of action, and their regulation. Significant studies on phospholipases characterization, physiological role, and industrial potential have been conducted worldwide. Some of them have been directed for biotechnological advances, such as gene discovery and functional enhancement by protein engineering. Others reported phospholipases as virulence factors and major causes of pathophysiological effects. In this introductory chapter, we provide brief details of different phospholipases.
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Affiliation(s)
- Ahmed Aloulou
- National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia.
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Karray A, Zarai Z, Gargouri Y, Verger R, Bezzine S. Kinetic properties of pancreatic and intestinal sPLA2 from chicken and mammals using the monomolecular film technique. J Colloid Interface Sci 2011; 363:620-5. [DOI: 10.1016/j.jcis.2011.07.041] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 07/12/2011] [Accepted: 07/14/2011] [Indexed: 11/25/2022]
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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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Watanabe K, Fujioka D, Saito Y, Nakamura T, Obata JE, Kawabata K, Watanabe Y, Mishina H, Tamaru S, Hanasaki K, Kugiyama K. Group X secretory PLA2 in neutrophils plays a pathogenic role in abdominal aortic aneurysms in mice. Am J Physiol Heart Circ Physiol 2011; 302:H95-104. [PMID: 21984544 DOI: 10.1152/ajpheart.00695.2011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Group X secretory PLA(2) (sPLA(2)-X) is expressed in neutrophils and plays a role in the pathogenesis of neutrophil-mediated tissue inflammation and injury. This study tested the hypothesis that sPLA(2)-X in neutrophils may contribute to the pathogenesis of abdominal aortic aneurysms (AAA) using sPLA(2)-X(-/-) mice. AAA was created by application of CaCl(2) to external surface of aorta. As a result, the aortas of sPLA(2)-X(-/-) mice had smaller diameters (percent increase from baseline; 24.8 ± 3.5% vs. 49.9 ± 9.1%, respectively; P < 0.01), a reduced grade of elastin degradation, and lower activities of elastase and gelatinase (26% and 19% lower, respectively) after CaCl(2) treatment compared with sPLA(2)-X(+/+) mice. In sPLA(2)-X(+/+) mice, immunofluorescence microscopic images showed that the immunoreactivity of sPLA(2)-X was detected only in neutrophils within aortic walls 3 days, 1, 2, and 6 wk after CaCl(2) treatment, whereas the immunoreactivity was not detected in macrophages or mast cells in aortic walls. sPLA(2)-X immunoreactivity also was colocalized in cells expressing matrix metalloproteinase (MMP)-9. Neutrophils isolated from sPLA(2)-X(-/-) mice had lower activities of elastase, gelatinase, and MMP-9 in response to stimuli compared with sPLA(2)-X(+/+) mice. The attenuated release of elastase and gelatinase from sPLA(2)-X(-/-) neutrophils was reversed by exogenous addition of mouse sPLA(2)-X protein. The adoptive transfer of sPLA(2)-X(+/+) neutrophils days 0 and 3 after CaCl(2) treatment reversed aortic diameters and elastin degradation grades in the lethally irradiated sPLA(2)-X(+/+) mice reconstituted with sPLA(2)-X(-/-) bone marrow to an extent similar to that seen in sPLA(2)-X(+/+) mice. In conclusion, sPLA(2)-X in neutrophils plays a pathogenic role in AAA in a mice model.
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Affiliation(s)
- Kazuhiro Watanabe
- Department of Internal Medicine II, University of Yamanashi, Chuo, Japan
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Jemel I, Ii H, Oslund RC, Payré C, Dabert-Gay AS, Douguet D, Chargui K, Scarzello S, Gelb MH, Lambeau G. Group X secreted phospholipase A2 proenzyme is matured by a furin-like proprotein convertase and releases arachidonic acid inside of human HEK293 cells. J Biol Chem 2011; 286:36509-21. [PMID: 21878635 DOI: 10.1074/jbc.m111.268540] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Among mammalian secreted phospholipases A(2) (sPLA(2)s), group X sPLA(2) has the most potent hydrolyzing activity toward phosphatidylcholine and is involved in arachidonic acid (AA) release. Group X sPLA(2) is produced as a proenzyme and contains a short propeptide of 11 amino acids ending with a dibasic motif, suggesting cleavage by proprotein convertases. Although the removal of this propeptide is clearly required for enzymatic activity, the cellular location and the protease(s) involved in proenzyme conversion are unknown. Here we have analyzed the maturation of group X sPLA(2) in HEK293 cells, which have been extensively used to analyze sPLA(2)-induced AA release. Using recombinant mouse (PromGX) and human (ProhGX) proenzymes; HEK293 cells transfected with cDNAs coding for full-length ProhGX, PromGX, and propeptide mutants; and various permeable and non-permeable sPLA(2) inhibitors and protease inhibitors, we demonstrate that group X sPLA(2) is mainly converted intracellularly and releases AA before externalization from the cell. Most strikingly, the exogenous proenzyme does not elicit AA release, whereas the transfected proenzyme does elicit AA release in a way insensitive to non-permeable sPLA(2) inhibitors. In transfected cells, a permeable proprotein convertase inhibitor, but not a non-permeable one, prevents group X sPLA(2) maturation and partially blocks AA release. Mutations at the dibasic motif of the propeptide indicate that the last basic residue is required and sufficient for efficient maturation and AA release. All together, these results argue for the intracellular maturation of group X proenzyme in HEK293 cells by a furin-like proprotein convertase, leading to intracellular release of AA during secretion.
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Affiliation(s)
- Ikram Jemel
- Institut de Pharmacologie Moléculaire et Cellulaire, UMR6097, CNRS et Université de Nice-Sophia-Antipolis, 660 Route des Lucioles, Sophia Antipolis, 06560 Valbonne, France
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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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Shridas P, Bailey WM, Talbott KR, Oslund RC, Gelb MH, Webb NR. Group X secretory phospholipase A2 enhances TLR4 signaling in macrophages. THE JOURNAL OF IMMUNOLOGY 2011; 187:482-9. [PMID: 21622863 DOI: 10.4049/jimmunol.1003552] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Secretory phospholipase A(2)s (sPLA(2)) hydrolyze glycerophospholipids to liberate lysophospholipids and free fatty acids. Although group X (GX) sPLA(2) is recognized as the most potent mammalian sPLA(2) in vitro, its precise physiological function(s) remains unclear. We recently reported that GX sPLA(2) suppresses activation of the liver X receptor in macrophages, resulting in reduced expression of liver X receptor-responsive genes including ATP-binding cassette transporters A1 (ABCA1) and G1 (ABCG1), and a consequent decrease in cellular cholesterol efflux and increase in cellular cholesterol content (Shridas et al. 2010. Arterioscler. Thromb. Vasc. Biol. 30: 2014-2021). In this study, we provide evidence that GX sPLA(2) modulates macrophage inflammatory responses by altering cellular cholesterol homeostasis. Transgenic expression or exogenous addition of GX sPLA(2) resulted in a significantly higher induction of TNF-α, IL-6, and cyclooxygenase-2 in J774 macrophage-like cells in response to LPS. This effect required GX sPLA(2) catalytic activity, and was abolished in macrophages that lack either TLR4 or MyD88. The hypersensitivity to LPS in cells overexpressing GX sPLA(2) was reversed when cellular free cholesterol was normalized using cyclodextrin. Consistent with results from gain-of-function studies, peritoneal macrophages from GX sPLA(2)-deficient mice exhibited a significantly dampened response to LPS. Plasma concentrations of inflammatory cytokines were significantly lower in GX sPLA(2)-deficient mice compared with wild-type mice after LPS administration. Thus, GX sPLA(2) amplifies signaling through TLR4 by a mechanism that is dependent on its catalytic activity. Our data indicate this effect is mediated through alterations in plasma membrane free cholesterol and lipid raft content.
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Affiliation(s)
- Preetha Shridas
- University of Kentucky Medical Center, Lexington, KY 40536, USA.
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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, Frikha F, Ben Ali Y, Gargouri Y, Bezzine S. Purification and biochemical characterization of a secreted group IIA chicken intestinal phospholipase A₂. Lipids Health Dis 2011; 10:27. [PMID: 21284884 PMCID: PMC3040156 DOI: 10.1186/1476-511x-10-27] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2010] [Accepted: 02/01/2011] [Indexed: 02/05/2023] Open
Abstract
Background Secretory phospholipase A2 group IIA (IIA PLA2) is a protein shown to be highly expressed in the intestine of mammals. However, no study was reported in birds. Results Chicken intestinal group IIA phospholipase A2 (ChPLA2-IIA) was obtained after an acidic treatment (pH.3.0), precipitation by ammonium sulphate, followed by sequential column chromatographies on Sephadex G-50 and mono-S ion exchanger. The enzyme was found to be a monomeric protein with a molecular mass of around 14 kDa. The purified enzyme showed a substrate preference for phosphatidylethanolamine and phosphatidylglycerol, and didn't hydrolyse phosphatidylcholine. Under optimal assay conditions, in the presence of 10 mM NaTDC and 10 mM CaCl2, a specific activity of 160 U.mg-1 for purified ChPLA2-IIA was measured using egg yolk as substrate. The fifteen NH2-terminal amino acid residues of ChPLA2-IIA were sequenced and showed a close homology with known intestinal secreted phospholipases A2. The gene encoding the mature ChPLA2-IIA was cloned and sequenced. To further investigate structure-activity relationship, a 3D model of ChPLA2-IIA was built using the human intestinal phospholipase A2 structure as template. Conclusion ChPLA2-IIA was purified to homogeneity using only two chromatographic colomns. Sequence analysis of the cloned cDNA indicates that the enzyme is highly basic with a pI of 9.0 and has a high degree of homology with mammalian intestinal PLA2-IIA.
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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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Yamamoto K, Taketomi Y, Isogai Y, Miki Y, Sato H, Masuda S, Nishito Y, Morioka K, Ishimoto Y, Suzuki N, Yokota Y, Hanasaki K, Ishikawa Y, Ishii T, Kobayashi T, Fukami K, Ikeda K, Nakanishi H, Taguchi R, Murakami M. Hair follicular expression and function of group X secreted phospholipase A2 in mouse skin. J Biol Chem 2011; 286:11616-31. [PMID: 21266583 DOI: 10.1074/jbc.m110.206714] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Although perturbed lipid metabolism can often lead to skin abnormality, the role of phospholipase A(2) (PLA(2)) in skin homeostasis is poorly understood. In the present study we found that group X-secreted PLA(2) (sPLA(2)-X) was expressed in the outermost epithelium of hair follicles in synchrony with the anagen phase of hair cycling. Transgenic mice overexpressing sPLA(2)-X (PLA2G10-Tg) displayed alopecia, which was accompanied by hair follicle distortion with reduced expression of genes related to hair development, during a postnatal hair cycle. Additionally, the epidermis and sebaceous glands of PLA2G10-Tg skin were hyperplasic. Proteolytic activation of sPLA(2)-X in PLA2G10-Tg skin was accompanied by preferential hydrolysis of phosphatidylethanolamine species with polyunsaturated fatty acids as well as elevated production of some if not all eicosanoids. Importantly, the skin of Pla2g10-deficient mice had abnormal hair follicles with noticeable reduction in a subset of hair genes, a hypoplasic outer root sheath, a reduced number of melanin granules, and unexpected up-regulation of prostanoid synthesis. Collectively, our study highlights the spatiotemporal expression of sPLA(2)-X in hair follicles, the presence of skin-specific machinery leading to sPLA(2)-X activation, a functional link of sPLA(2)-X with hair follicle homeostasis, and compartmentalization of the prostanoid pathway in hair follicles and epidermis.
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Affiliation(s)
- Kei Yamamoto
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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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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