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Coras R, Murillo-Saich JD, Singh AG, Kavanaugh A, Guma M. Lipidomic Profiling in Synovial Tissue. Front Med (Lausanne) 2022; 9:857135. [PMID: 35492314 PMCID: PMC9051397 DOI: 10.3389/fmed.2022.857135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 03/14/2022] [Indexed: 11/13/2022] Open
Abstract
The analysis of synovial tissue offers the potential for the comprehensive characterization of cell types involved in arthritis pathogenesis. The studies performed to date in synovial tissue have made it possible to define synovial pathotypes, which relate to disease severity and response to treatment. Lipidomics is the branch of metabolomics that allows the quantification and identification of lipids in different biological samples. Studies in animal models of arthritis and in serum/plasma from patients with arthritis suggest the involvement of different types of lipids (glycerophospholipids, glycerolipids, sphingolipids, oxylipins, fatty acids) in the pathogenesis of arthritis. We reviewed studies that quantified lipids in different types of tissues and their relationship with inflammation. We propose that combining lipidomics with currently used “omics” techniques can improve the information obtained from the analysis of synovial tissue, for a better understanding of pathogenesis and the development of new therapeutic strategies.
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Affiliation(s)
- Roxana Coras
- Department of Medicine, School of Medicine, University of California, San Diego, San Diego, CA, United States
- Department of Medicine, Autonomous University of Barcelona, Barcelona, Spain
| | - Jessica D. Murillo-Saich
- Department of Medicine, School of Medicine, University of California, San Diego, San Diego, CA, United States
| | - Abha G. Singh
- Department of Medicine, School of Medicine, University of California, San Diego, San Diego, CA, United States
| | - Arthur Kavanaugh
- Department of Medicine, School of Medicine, University of California, San Diego, San Diego, CA, United States
| | - Monica Guma
- Department of Medicine, School of Medicine, University of California, San Diego, San Diego, CA, United States
- Department of Medicine, Autonomous University of Barcelona, Barcelona, Spain
- San Diego VA Healthcare Service, San Diego, CA, United States
- *Correspondence: Monica Guma
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Feldman M, Ginsburg I. A Novel Hypothetical Approach to Explain the Mechanisms of Pathogenicity of Rheumatic Arthritis. Mediterr J Rheumatol 2021; 32:112-117. [PMID: 34447906 PMCID: PMC8369279 DOI: 10.31138/mjr.32.2.112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/29/2020] [Accepted: 10/15/2020] [Indexed: 12/29/2022] Open
Abstract
The autoimmune disorder rheumatoid arthritis (RA) is a relapsing and chronic inflammatory disease that affects the synovial cells, cartilage, bone, and muscle. It is characterised by the accumulation of huge numbers of polymorphonuclear neutrophils (PMNs) and macrophages in the synovia. Auto-antibodies are deposited in the joint via the activity of highly cationic histones released from neutrophil extracellular traps (NETs) in a phenomenon termed NETosis. The cationic histones function as opsonic agents that bind to negatively charged domains in autoantibodies and complement compounds via strong electrostatic forces, facilitating their deposition and endocytosis by synovial cells. However, eventually the main cause of tissue damage is the plethora of toxic pro-inflammatory substances released by activated neutrophils recruited by cytokines. Tissue damage in RA can also be accompanied by infections which, upon bacteriolysis, release cell-wall components that are toxic to tissues. Some amelioration of the damaged cells and tissues in RA may be achieved by the use of highly anionic heparins, which can neutralize cationic histone activity, provided that these polyanions are co-administrated with anti-inflammatory drugs such as steroids, colchicine, or methotrexate, low molecular weight antioxidants, proteinase inhibitors, and phospholipase A2 inhibitors.
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Affiliation(s)
- Mark Feldman
- Institute for Dental Sciences, the Hebrew University - Hadassah Faculty of Dental Medicine, Ein Kerem Campus, Jerusalem, Israel
| | - Isaac Ginsburg
- Institute for Dental Sciences, the Hebrew University - Hadassah Faculty of Dental Medicine, Ein Kerem Campus, Jerusalem, Israel
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Stien D, Suzuki M, Rodrigues AMS, Yvin M, Clergeaud F, Thorel E, Lebaron P. A unique approach to monitor stress in coral exposed to emerging pollutants. Sci Rep 2020; 10:9601. [PMID: 32541793 PMCID: PMC7295770 DOI: 10.1038/s41598-020-66117-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 04/15/2020] [Indexed: 11/29/2022] Open
Abstract
Metabolomic profiling of the hexacoral Pocillopora damicornis exposed to solar filters revealed a metabolomic signature of stress in this coral. It was demonstrated that the concentration of the known steroid (3β, 5α, 8α) -5, 8-epidioxy- ergosta- 6, 24(28) - dien- 3- ol (14) increased in response to octocrylene (OC) and ethylhexyl salicylate (ES) at 50 µg/L. Based on the overall coral response, we hypothesize that steroid 14 mediates coral response to stress. OC also specifically altered mitochondrial function at this concentration and above, while ES triggered a stress/inflammatory response at 300 µg/L and above as witnessed by the significant increases in the concentrations of polyunsaturated fatty acids, lysophosphatidylcholines and lysophosphatidylethanolamines. Benzophenone-3 increased the concentration of compound 14 at 2 mg/L, while the concentration of stress marker remained unchanged upon exposition to the other solar filters tested. Also, our results seemed to refute earlier suggestions that platelet-activating factor is involved in the coral inflammatory response.
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Affiliation(s)
- Didier Stien
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France.
| | - Marcelino Suzuki
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Alice M S Rodrigues
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Marion Yvin
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Fanny Clergeaud
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Evane Thorel
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Philippe Lebaron
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
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Xue M, Dervish S, McKelvey KJ, March L, Wang F, Little CB, Jackson CJ. Activated protein C targets immune cells and rheumatoid synovial fibroblasts to prevent inflammatory arthritis in mice. Rheumatology (Oxford) 2019; 58:1850-1860. [DOI: 10.1093/rheumatology/key429] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
Abstract
AbstractObjectivesTo investigate whether activated protein C (APC), a physiological anticoagulant can inhibit the inflammatory/invasive properties of immune cells and rheumatoid arthritis synovial fibroblasts (RASFs) in vitro and prevent inflammatory arthritis in murine antigen-induced arthritis (AIA) and CIA models.MethodsRASFs isolated from synovial tissues of patients with RA, human peripheral blood mononuclear cells (PBMCs) and mouse thymus cells were treated with APC or TNF-α/IL-17 and the following assays were performed: RASF proliferation and invasion by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and cell invasion assays, respectively; cytokines and signalling molecules using ELISA or western blot; Th1 and Th17 phenotypes in human PBMCs or mouse thymus cells by flow cytometry. The in vivo effect of APC was evaluated in AIA and CIA models.ResultsIn vitro, APC inhibited IL-1β, IL-17 and TNF-α production, IL-17-stimulated cell proliferation and invasion and p21 and nuclear factor κB activation in RASFs. In mouse thymus cells and human PBMCs, APC suppressed Th1 and Th17 phenotypes. In vivo, APC inhibited pannus formation, cartilage destruction and arthritis incidence/severity in both CIA and AIA models. In CIA, serum levels of IL-1β, IL-6, IL-17, TNF-α and soluble endothelial protein C receptor were significantly reduced by APC treatment. Blocking endothelial protein C receptor, the specific receptor for APC, abolished the early or preventative effect of APC in AIA.ConclusionAPC prevents the onset and development of arthritis in CIA and AIA models via suppressing inflammation, Th1/Th17 phenotypes and RASF invasion, which is likely mediated via endothelial protein C receptor.
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Affiliation(s)
- Meilang Xue
- Sutton Arthritis Research Laboratories, Institute of Bone and Joint Research, Kolling Institute of Medical Research
| | - Suat Dervish
- Sutton Arthritis Research Laboratories, Institute of Bone and Joint Research, Kolling Institute of Medical Research
| | - Kelly J McKelvey
- Sutton Arthritis Research Laboratories, Institute of Bone and Joint Research, Kolling Institute of Medical Research
| | - Lyn March
- Department of Rheumatology, University of Sydney at Royal North Shore Hospital, St Leonards, NSW, Australia
| | - Fang Wang
- Department of Cardiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Chris B Little
- Raymond Purves Bone and Joint Research Laboratories, Institute of Bone and Joint Research, Kolling Institute of Medical Research, University of Sydney at Royal North Shore Hospital, St Leonards, NSW, Australia
| | - Christopher J Jackson
- Sutton Arthritis Research Laboratories, Institute of Bone and Joint Research, Kolling Institute of Medical Research
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MARQUES TAMARAR, BRAGA MARIANAA, CESAR PEDROH, MARCUSSI SILVANA, CORRÊA ANGELITAD. Jabuticaba (Plinia jaboticaba) skin extracts as inhibitors of phospholipases A2 and proteases. ACTA ACUST UNITED AC 2019; 91:e20180248. [DOI: 10.1590/0001-3765201920180248] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Accepted: 08/08/2018] [Indexed: 12/13/2022]
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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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Phospholipase A 2 catalysis and lipid mediator lipidomics. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:766-771. [PMID: 30905345 DOI: 10.1016/j.bbalip.2018.08.010] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 08/10/2018] [Accepted: 08/16/2018] [Indexed: 01/09/2023]
Abstract
Phospholipase A2 (PLA2) enzymes are the upstream regulators of the eicosanoid pathway liberating free arachidonic acid from the sn-2 position of membrane phospholipids. Free intracellular arachidonic acid serves as a substrate for the eicosanoid biosynthetic enzymes including cyclooxygenases, lipoxygenases, and cytochrome P450s that lead to inflammation. The Group IVA cytosolic (cPLA2), Group VIA calcium-independent (iPLA2), and Group V secreted (sPLA2) are three well-characterized human enzymes that have been implicated in eicosanoid formation. In this review, we will introduce and summarize the regulation of catalytic activity and cellular localization, structural characteristics, interfacial activation and kinetics, substrate specificity, inhibitor binding and interactions, and the downstream implications for eicosanoid biosynthesis of these three important PLA2 enzymes.
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Lin XH, Xu MT, Tang JY, Mai LF, Wang XY, Ren M, Yan L. Effect of intensive insulin treatment on plasma levels of lipoprotein-associated phospholipase A 2 and secretory phospholipase A 2 in patients with newly diagnosed type 2 diabetes. Lipids Health Dis 2016; 15:203. [PMID: 27881128 PMCID: PMC5120429 DOI: 10.1186/s12944-016-0368-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 11/10/2016] [Indexed: 02/06/2023] Open
Abstract
Background China has the highest absolute disease burden of diabetes worldwide. For diabetic patients, diabetes-related vascular complications are major causes of morbidity and mortality. The roles of lipoprotein-associated phospholipase A2 (Lp-PLA2) and secretory phospholipase A2 (sPLA2) as inflammatory markers have been recently evaluated in the pathogenesis of both diabetes and atherosclerosis. We aimed to determine the mechanism through which patients with newly diagnosed type 2 diabetes gain long-term vascular benefit from intensive insulin therapy by evaluating the change in Lp-PLA2 and sPLA2 levels after early intensive insulin treatment and its relevance with insulin resistance and pancreatic β-cell function. Methods In total, 90 patients with newly diagnosed type 2 diabetes mellitus were enrolled. All patients received continuous subcutaneous insulin infusion (CSII) for approximately 2 weeks. Intravenous glucose-tolerance test (IVGTT) and oral glucose-tolerance test (OGTT) were performed, and plasma concentrations of Lp-PLA2 and sPLA2 were measured before and after CSII. Results Levels of Lp-PLA2 and sPLA2 were significantly higher in diabetic patients with macroangiopathy than in those without (P < 0.05). After CSII, the sPLA2 level decreased significantly in all diabetic patients (P < 0.05), while the Lp-PLA2 level changed only in those with macroangiopathy (P < 0.05). The area under the curve of insulin in IVGTT and OGTT, the acute insulin response (AIR3–5), early phase of insulin secretion (ΔIns30/ΔG30), modified β-cell function index, and homeostatic model assessment for β-cell function (HOMA-β) increased after treatment even when adjusted for the influence of insulin resistance (IR; P < 0.001). The HOMA-IR was lower after treatment, and the three other indicators adopted to estimate insulin sensitivity (ISIced, IAI, and QUICKI) were higher after treatment (P < 0.05). Correlation analysis showed that the decrease in the Lp-PLA2 and sPLA2 levels was positively correlated with a reduction in HOMA-IR after CSII (P < 0.05). Additionally, multiple linear regression analysis showed that Lp-PLA2 and sPLA2 independently correlated with HOMA-IR (P < 0.05). Conclusions Lp-PLA2 and sPLA2 are closely related to insulin resistance and macroangiopathy in diabetic patients. Intensive insulin therapy might help improve IR and protect against diabetic macroangiopathy by influencing the Lp-PLA2 and sPLA2 levels. Trial registration ChiCTR-TRC-10001618 2010 September 16.
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Affiliation(s)
- Xiu-Hong Lin
- Department of Clinical Nutrition, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou, 510120, People's Republic of China
| | - Ming-Tong Xu
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou, 510120, People's Republic of China.
| | - Jv-Ying Tang
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou, 510120, People's Republic of China
| | - Li-Fang Mai
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou, 510120, People's Republic of China
| | - Xiao-Yi Wang
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou, 510120, People's Republic of China
| | - Meng Ren
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou, 510120, People's Republic of China
| | - Li Yan
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou, 510120, People's Republic of China
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Computer-aided drug design guided by hydrogen/deuterium exchange mass spectrometry: A powerful combination for the development of potent and selective inhibitors of Group VIA calcium-independent phospholipase A 2. Bioorg Med Chem 2016; 24:4801-4811. [PMID: 27320659 DOI: 10.1016/j.bmc.2016.05.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 05/05/2016] [Accepted: 05/09/2016] [Indexed: 11/20/2022]
Abstract
Potent and selective inhibitors for phospholipases A2 (PLA2) are useful for studying their intracellular functions. PLA2 enzymes liberate arachidonic acid from phospholipids activating eicosanoid pathways that involve cyclooxygenase (COX) and lipoxygenase (LOX) leading to inflammation. Anti-inflammatory drugs target COX and LOX; thus, PLA2 can also be targeted to diminish inflammation at an earlier stage in the process. This paper describes the employment of enzymatic assays, hydrogen/deuterium exchange mass spectrometry (DXMS) and computational chemistry to develop PLA2 inhibitors. Beta-thioether trifluoromethylketones (TFKs) were screened against human GVIA calcium-independent, GIVA cytosolic and GV secreted PLA2s. These compounds exhibited inhibition toward Group VIA calcium-independent PLA2 (GVIA iPLA2), with the most potent and selective inhibitor 3 (OTFP) obtaining an XI(50) of 0.0002 mole fraction (IC50 of 110nM). DXMS binding experiments in the presence of OTFP revealed the peptide regions of GVIA iPLA2 that interact with the inhibitor. Molecular docking and dynamics simulations in the presence of a membrane were guided by the DXMS data in order to identify the binding mode of OTFP. Clustering analysis showed the binding mode of OTFP that occupied 70% of the binding modes occurring during the simulation. The resulted 3D complex was used for docking studies and a structure-activity relationship (SAR) was established. This paper describes a novel multidisciplinary approach in which a 3D complex of GVIA iPLA2 with an inhibitor is reported and validated by experimental data. The SAR showed that the sulfur atom is vital for the potency of beta-thioether analogues, while the hydrophobic chain is important for selectivity. This work constitutes the foundation for further design, synthesis and inhibition studies in order to develop new beta-thioether analogues that are potent and selective for GVIA iPLA2 exclusively.
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Mouchlis VD, Limnios D, Kokotou MG, Barbayianni E, Kokotos G, McCammon JA, Dennis EA. Development of Potent and Selective Inhibitors for Group VIA Calcium-Independent Phospholipase A2 Guided by Molecular Dynamics and Structure-Activity Relationships. J Med Chem 2016; 59:4403-14. [PMID: 27087127 DOI: 10.1021/acs.jmedchem.6b00377] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The development of inhibitors for phospholipase A2 (PLA2) is important in elucidating the enzymes implication in various biological pathways. PLA2 enzymes are an important pharmacological target implicated in various inflammatory diseases. Computational chemistry, organic synthesis, and in vitro assays were employed to develop potent and selective inhibitors for group VIA calcium-independent PLA2. A set of fluoroketone inhibitors was studied for their binding mode with two human cytosolic PLA2 enzymes: group IVA cPLA2 and group VIA iPLA2. New compounds were synthesized and assayed toward three major PLA2s. This study led to the development of four potent and selective thioether fluoroketone inhibitors as well as a thioether keto-1,2,4-oxadiazole inhibitor for GVIA iPLA2, which will serve as lead compounds for future development and studies. The keto-1,2,4-oxadiazole functionality with a thioether is a novel structure, and it will be used as a lead to develop inhibitors with higher potency and selectivity toward GVIA iPLA2.
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Affiliation(s)
- Varnavas D Mouchlis
- Department of Pharmacology and Department of Chemistry and Biochemistry, School of Medicine, University of California, San Diego , La Jolla, California 92093-0601, United States
| | - Dimitris Limnios
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771, Greece
| | - Maroula G Kokotou
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771, Greece
| | - Efrosini Barbayianni
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771, Greece
| | - George Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771, Greece
| | - J Andrew McCammon
- Department of Pharmacology and Department of Chemistry and Biochemistry, School of Medicine, University of California, San Diego , La Jolla, California 92093-0601, United States
| | - Edward A Dennis
- Department of Pharmacology and Department of Chemistry and Biochemistry, School of Medicine, University of California, San Diego , La Jolla, California 92093-0601, United States
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Liu NJ, Chapman R, Lin Y, Mmesi J, Bentham A, Tyreman M, Abraham S, Stevens MM. Point of care testing of phospholipase A2 group IIA for serological diagnosis of rheumatoid arthritis. NANOSCALE 2016; 8:4482-5. [PMID: 26854217 DOI: 10.1039/c5nr08423g] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Secretory phospholipase A2 group IIA (sPLA2-IIA) was examined as a point of care marker for determining disease activity in rheumatoid (RA) and psoriatic (PsA) arthritis. Serum concentration and activity of sPLA2-IIA were measured using in-house antibodies and a novel point of care lateral flow device assay in patients diagnosed with varying severities of RA (n = 30) and PsA (n = 25) and found to correlate strongly with C-reactive protein (CRP). Levels of all markers were elevated in patients with active RA over those with inactive RA as well as both active and inactive PsA, indicating that sPLA2-IIA can be used as an analogue to CRP for RA diagnosis at point of care.
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Affiliation(s)
- Nathan J Liu
- Department of Materials, Department of Bioengineering and Institute for Biomedical Engineering, Imperial College London, London SW7 2AZ, UK. and Department of Medicine and Clinical Research Facility, Faculty of Medicine, Imperial College London, London, W12 0NN, UK
| | - Robert Chapman
- Department of Materials, Department of Bioengineering and Institute for Biomedical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Yiyang Lin
- Department of Materials, Department of Bioengineering and Institute for Biomedical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Jonas Mmesi
- Department of Medicine and Clinical Research Facility, Faculty of Medicine, Imperial College London, London, W12 0NN, UK
| | - Andrew Bentham
- Mologic Ltd., Bedford Technology Park, Thurleigh, Bedfordshire MK44 2YP, UK
| | - Matthew Tyreman
- Mologic Ltd., Bedford Technology Park, Thurleigh, Bedfordshire MK44 2YP, UK
| | - Sonya Abraham
- Department of Medicine and Clinical Research Facility, Faculty of Medicine, Imperial College London, London, W12 0NN, UK
| | - Molly M Stevens
- Department of Materials, Department of Bioengineering and Institute for Biomedical Engineering, Imperial College London, London SW7 2AZ, UK.
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Membrane and inhibitor interactions of intracellular phospholipases A2. Adv Biol Regul 2015; 61:17-24. [PMID: 26774606 DOI: 10.1016/j.jbior.2015.11.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 11/19/2015] [Accepted: 11/20/2015] [Indexed: 02/06/2023]
Abstract
Studying phospholipases A2 (PLA2s) is a challenging task since they act on membrane-like aggregated substrates and not on monomeric phospholipids. Multidisciplinary approaches that include hydrogen/deuterium exchange mass spectrometry (DXMS) and computational techniques have been employed with great success in order to address important questions about the mode of interactions of PLA2 enzymes with membranes, phospholipid substrates and inhibitors. Understanding the interactions of PLA2s is crucial since these enzymes are the upstream regulators of the eicosanoid pathway liberating free arachidonic acid (AA) and other polyunsaturated fatty acids (PUFA). The liberation of AA by PLA2 enzymes sets off a cascade of molecular events that involves downstream regulators such as cyclooxygenase (COX) and lipoxygenase (LOX) metabolites leading to inflammation. Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) work by inhibiting COX, while Zileuton inhibits LOX and both rely on PLA2 enzymes to provide them with AA. That means PLA2 enzymes can potentially also be targeted to diminish inflammation at an earlier point in the process. In this review we describe extensive efforts reported in the past to define the interactions of PLA2 enzymes with membranes, substrate phospholipids and inhibitors using DXMS, molecular docking, and molecular dynamics (MD) simulations.
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Cytosolic phospholipase A2 modulates TLR2 signaling in synoviocytes. PLoS One 2015; 10:e0119088. [PMID: 25893499 PMCID: PMC4404349 DOI: 10.1371/journal.pone.0119088] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 01/09/2015] [Indexed: 12/29/2022] Open
Abstract
Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic synovitis leading to destruction of cartilage and bone. PLA2 enzymes are key players in inflammation regulating the release of unsaturated fatty acids such as arachidonic acid (AA), a precursor of pro-inflammatory eicosanoids. Several lines of evidence point to toll-like receptors (TLRs) as drivers of synovitis and joint destruction in RA. However, few studies have addressed the implication of PLA2 activity downstream TLR activation in the synovium. Here, we aimed to characterize PLA2 enzyme involvement in TLR2-induced signaling in synovial fibroblast-like cells. TLRs1-7 and a range of sPLA2, iPLA2 and cPLA2 enzymes were found to be transcriptionally expressed in cultured synoviocytes. Activation of TLR2/1 and TLR2/6 led to phosphorylation of cPLA2α at Ser505, and induced AA release and PGE2 production; effects that were attenuated by cPLA2α inhibitors. In contrast, sPLA2 inhibitors did not affect AA or PGE2 release. cPLA2α inhibitors furthermore attenuated TLR-induced expression of IL-6, IL-8 and COX2. COX1/2 inhibitors attenuated TLR2/6-induced IL-6 transcription and protein production comparable to cPLA2α inhibition. Moreover, exogenously PGE2 added alone induced IL-6 production and completely rescued IL-6 transcription when added simultaneously with FSL-1 in the presence of a cPLA2α inhibitor. Our results demonstrate for the first time that cPLA2α is involved in TLR2/1- and TLR2/6-induced AA release, PGE2 production and pro-inflammatory cytokine expression in synoviocytes, possibly through COX/PGE2-dependent pathways. These findings expand our understanding of cPLA2α as a modulator of inflammatory molecular mechanisms in chronic diseases such as RA.
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Mouchlis VD, Bucher D, McCammon JA, Dennis EA. Membranes serve as allosteric activators of phospholipase A2, enabling it to extract, bind, and hydrolyze phospholipid substrates. Proc Natl Acad Sci U S A 2015; 112:E516-25. [PMID: 25624474 PMCID: PMC4330758 DOI: 10.1073/pnas.1424651112] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Defining the molecular details and consequences of the association of water-soluble proteins with membranes is fundamental to understanding protein-lipid interactions and membrane functioning. Phospholipase A2 (PLA2) enzymes, which catalyze the hydrolysis of phospholipid substrates that compose the membrane bilayers, provide the ideal system for studying protein-lipid interactions. Our study focuses on understanding the catalytic cycle of two different human PLA2s: the cytosolic Group IVA cPLA2 and calcium-independent Group VIA iPLA2. Computer-aided techniques guided by deuterium exchange mass spectrometry data, were used to create structural complexes of each enzyme with a single phospholipid substrate molecule, whereas the substrate extraction process was studied using steered molecular dynamics simulations. Molecular dynamic simulations of the enzyme-substrate-membrane systems revealed important information about the mechanisms by which these enzymes associate with the membrane and then extract and bind their phospholipid substrate. Our data support the hypothesis that the membrane acts as an allosteric ligand that binds at the allosteric site of the enzyme's interfacial surface, shifting its conformation from a closed (inactive) state in water to an open (active) state at the membrane interface.
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Affiliation(s)
| | | | - J Andrew McCammon
- Departments of Pharmacology and Chemistry and Biochemistry, and Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093-0601
| | - Edward A Dennis
- Departments of Pharmacology and Chemistry and Biochemistry, and
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Xue M, Shen K, McKelvey K, Li J, Chan YKA, Hatzis V, March L, Little CB, Tonkin M, Jackson CJ. Endothelial protein C receptor-associated invasiveness of rheumatoid synovial fibroblasts is likely driven by group V secretory phospholipase A2. Arthritis Res Ther 2014; 16:R44. [PMID: 24495480 PMCID: PMC3979138 DOI: 10.1186/ar4473] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 01/28/2014] [Indexed: 01/24/2023] Open
Abstract
INTRODUCTION Rheumatoid synovial fibroblasts (RASFs) mediate joint inflammation and destruction in rheumatoid arthritis (RA). Endothelial protein C receptor (EPCR) is a specific receptor for the natural anticoagulant activated protein C (APC). It mediates the cytoprotective properties of APC and is expressed in rheumatoid synovial tissue. A recent report shows that group V secretory phospholipase A2 (sPLA₂V) prevents APC from binding to EPCR in endothelium and inhibits EPCR/APC function. The aim of this study was to investigate the expression and function of EPCR on RASFs. METHODS Human synovial fibroblasts (SFs) were isolated from RA or osteoarthritis (OA) synovial tissues and treated with control, EPCR, or sPLA₂V small interfering RNA (siRNA); recombinant human APC, tumor necrosis factor-alpha (TNF-α), or sPLA₂V. RASF viability and migration/invasion were measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and collagen gel migration/invasion assays, respectively, and cartilage degradation by 1,9-dimethylmethylene blue (DMMB) assay in the presence of human OA articular cartilage explants. The expression or activation of cytokines, EPCR, cadherin-11, mitogen-activated protein (MAP) kinases, and nuclear factor-kappa-B (NF-κB) or both were detected by enzyme-linked immunosorbent assay, Western blotting, or immunostaining. RESULTS EPCR was expressed by both OASFs and RASFs but was markedly increased in RASFs. When EPCR was suppressed by siRNA or blocking antibody cell viability, cell invasion and cartilage degradation were reduced by more than 30%. Inflammatory mediators interleukin-1-beta (IL-1β), cadherin-11, and NF-κB were significantly reduced by EPCR suppression under control or TNF-α-stimulated conditions. The expression or activation (or both) of MAP kinases ERK, p38, and JNK were also markedly decreased in cells transfected with EPCR siRNA. Further analysis revealed that sPLA₂V co-localized with EPCR on RASFs. Suppression of sPLA₂V reduced cell viability and cartilage degradation and increased APC binding to RASFs. Conversely, recombinant sPLA₂V increased cartilage degradation, blocked APC binding to RASFs, and could not rescue the effects induced by EPCR suppression. CONCLUSIONS Our results demonstrate that EPCR is overexpressed by RASFs and mediates the aggressive behavior of RASFs. This function of EPCR is contrary to its cytoprotective role in other settings and is likely driven by sPLA₂V.
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Nyegaard S, Novakovic VA, Rasmussen JT, Gilbert GE. Lactadherin inhibits secretory phospholipase A2 activity on pre-apoptotic leukemia cells. PLoS One 2013; 8:e77143. [PMID: 24194865 PMCID: PMC3806724 DOI: 10.1371/journal.pone.0077143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 08/21/2013] [Indexed: 01/09/2023] Open
Abstract
Secretory phospholipase A2 (sPLA2) is a critical component of insect and snake venoms and is secreted by mammalian leukocytes during inflammation. Elevated secretory PLA2 concentrations are associated with autoimmune diseases and septic shock. Many sPLA2’s do not bind to plasma membranes of quiescent cells but bind and digest phospholipids on the membranes of stimulated or apoptotic cells. The capacity of these phospholipases to digest membranes of stimulated or apoptotic cells correlates to the exposure of phosphatidylserine. In the present study, the ability of the phosphatidyl-L-serine-binding protein, lactadherin to inhibit phospholipase enzyme activity has been assessed. Inhibition of human secretory phospholipase A2-V on phospholipid vesicles exceeded 90%, whereas inhibition of Naja mossambica sPLA2 plateaued at 50–60%. Lactadherin inhibited 45% of activity of Naja mossambica sPLA2 and >70% of human secretory phospholipase A2-V on the membranes of human NB4 leukemia cells treated with calcium ionophore A23187. The data indicate that lactadherin may decrease inflammation by inhibiting sPLA2.
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Affiliation(s)
- Steffen Nyegaard
- Department of Molecular Biology, Aarhus University, Aarhus C, Denmark
- Departments of Medicine, Veterans Administration Boston Healthcare System, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Valerie A. Novakovic
- Departments of Medicine, Veterans Administration Boston Healthcare System, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jan T. Rasmussen
- Department of Molecular Biology, Aarhus University, Aarhus C, Denmark
- * E-mail:
| | - Gary E. Gilbert
- Departments of Medicine, Veterans Administration Boston Healthcare System, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
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Siroos B, Balood M, Zahednasab H, Mesbah-Namin SA, Pourgholy F, Harirchian MH. Secretory Phospholipase A2 activity in serum and cerebrospinal fluid of patients with relapsing-remitting multiple sclerosis. J Neuroimmunol 2013; 262:125-7. [DOI: 10.1016/j.jneuroim.2013.06.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 06/17/2013] [Accepted: 06/19/2013] [Indexed: 02/01/2023]
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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: 46] [Impact Index Per Article: 4.2] [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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Emerging roles of secreted phospholipase A2 enzymes: An update. Biochimie 2013; 95:43-50. [DOI: 10.1016/j.biochi.2012.09.007] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 09/11/2012] [Indexed: 01/18/2023]
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Potent and selective 2-oxoamide inhibitors of phospholipases A2 as novel medicinal agents for the treatment of inflammatory diseases. PURE APPL CHEM 2012. [DOI: 10.1351/pac-con-11-10-32] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Phospholipases A2 (PLA2s) are enzymes that are capable of catalyzing the hydrolysis of the sn-2 ester bond of glycerophospholipids, releasing free fatty acids, including arachidonic acid (AA), and lysophospholipids. Both products are precursor signaling molecules involved in inflammation. Among the various PLA2s, cytosolic GIVA cPLA2 is considered a major target for inflammatory diseases, while secreted GIIA sPLA2 is involved in cardiovascular diseases. We have developed lipophilic 2-oxoamides based on (S)-γ- or δ-amino acids as potent and selective inhibitors of GIVA cPLA2, which present interesting in vivo anti-inflammatory activity. 2-Oxoamides based on natural α-amino acids are selective inhibitors of GIIA sPLA2. The mode of binding of 2-oxoamides with either GIVA cPLA2 or GIIA sPLA2 has been studied by various techniques.
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Secreted phospholipase A2 group IIA is a neurotoxin released by stimulated human glial cells. Mol Cell Neurosci 2012; 49:430-8. [DOI: 10.1016/j.mcn.2012.02.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 02/20/2012] [Accepted: 02/21/2012] [Indexed: 12/21/2022] Open
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Keirstead ND, Hayes MA, Vandervoort GE, Brooks AS, Squires EJ, Lillie BN. Single nucleotide polymorphisms in collagenous lectins and other innate immune genes in pigs with common infectious diseases. Vet Immunol Immunopathol 2011; 142:1-13. [PMID: 21570129 DOI: 10.1016/j.vetimm.2011.02.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 02/15/2011] [Accepted: 02/18/2011] [Indexed: 02/06/2023]
Abstract
Innate immune recognition of pathogens involves various surface receptors and soluble proteins that precede agglutination, complement activation, phagocytosis, and the adaptive immune response. Mannan-binding lectins (MBLs), ficolins (FCNs) and surfactant protein A (SP-A) are soluble collagenous lectins that bind surface structures of various bacteria, viruses and fungi. Some single nucleotide polymorphisms (SNPs) in collagenous lectin genes of humans and other species, including pigs, have been implicated in variation in susceptibility to infectious and inflammatory diseases. In this study we determined the frequencies of 13 SNP alleles of MBL-A, MBL-C, ficolin-α, ficolin-β, and SP-A in 1324 healthy pigs and 461 pigs diagnosed with common infectious diseases at necropsy. For comparison, we also analyzed 12 other SNP alleles in several other innate immune genes, including galectins and TLRs. Several SNPs within genes encoding porcine MBL-A, MBL-C and SP-A were more frequent in pigs diagnosed at necropsy with various diseases or pathogens. These findings suggest that several collagenous lectin SNPs are associated with disease susceptibility and therefore might be genetic markers of impaired innate immune function.
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Affiliation(s)
- N D Keirstead
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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Wei Y, Epstein SP, Fukuoka S, Birmingham NP, Li XM, Asbell PA. sPLA2-IIa amplifies ocular surface inflammation in the experimental dry eye (DE) BALB/c mouse model. Invest Ophthalmol Vis Sci 2011; 52:4780-8. [PMID: 21519031 DOI: 10.1167/iovs.10-6350] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE sPLA2-IIa is a biomarker for many inflammatory diseases in humans and is found at high levels in human tears. However, its role in ocular surface inflammation remains unclear. An experimentally induced BALB/c mouse dry eye (DE) model was used to elucidate the role of sPLA2-IIa in ocular surface inflammation. METHODS BALB/c mice were subcutaneously injected with scopolamine and placed in a daytime air-drying device for 5 to 10 days. Control mice received no treatment. DE status was evaluated with tear production with a phenol-red thread method. Tear inflammatory cytokines were quantified by multiplex immunoassays. Ocular surface inflammation and sPLA2-IIa expression were examined by immune-staining and quantitative (q)RT(2)-PCR. Conjunctiva (CNJ) of the mice was cultured for prostaglandin E2 production induced by sPLA2-IIa with various amount of sPLA2-IIa inhibitor, S-3319. RESULTS Treated mice produced fewer tears and heavier corneal (CN) fluorescein staining than the untreated controls (P < 0.001). They also revealed lower goblet cell density (P < 0.001) with greater inflammatory cell infiltration within the conjunctiva, and higher concentration of tear inflammatory cytokines than the controls. Moreover, treated mice showed heavier sPLA2-IIa immune staining than the controls in the CNJ epithelium, but not in the CN epithelium or the lacrimal gland. Treated mice exhibited upregulated sPLA2-IIa and cytokine gene transcription. Furthermore, CNJ cultures treated with sPLA2-IIa inhibitor showed significantly reduced sPLA2-IIa-induced inflammation. CONCLUSIONS This is the first report regarding sPLA2-IIa in the regulation of ocular surface inflammation. The findings may therefore lead to new therapeutic strategies for ocular surface inflammation, such as DE disease.
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Affiliation(s)
- Yi Wei
- Department of Ophthalmology, Mount Sinai School of Medicine, New York, New York 10029, USA.
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Leistad L, Feuerherm AJ, Faxvaag A, Johansen B. Multiple phospholipase A2 enzymes participate in the inflammatory process in osteoarthritic cartilage. Scand J Rheumatol 2011; 40:308-16. [PMID: 21417548 DOI: 10.3109/03009742.2010.547872] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE The aim of this study was to determine the involvement of pro-inflammatory phospholipase A2 (PLA2) enzymes in human chondrocytes from patients with osteoarthritis (OA). METHODS PLA2 involvement in OA chondrocytes was analysed by (a) arachidonic acid (AA) and oleic acid release, (b) PLA2 mRNA analysis, and (c) prostaglandin E2 (PGE2) production in cultured OA chondrocytes in response to various cytokines and platelet activating factor (PAF). RESULTS Pro-inflammatory cytokines and PAF stimulation led to increased AA release, interleukin (IL)-1β and tumour necrosis factor (TNF) being the strongest inducers. The pattern of oleic acid release was similar to but less prominent than AA release, suggesting that predominantly arachidonyl selective enzymes were activated. IL-1β, TNF, IL-6, and IL-8 upregulated secretory group IIA, IID, and V phospholipase A2 (sPLA2-IIA, -IID, -V) and cytosolic group IVA phospholipase A2 (cPLA2-IVA) expression, where induction of chondrocyte sPLA2-IID is a novel finding. Furthermore, IL-1β, TNF, and IL-6 also induced COX2 expression. PAF induced expression of group IIA, IID and IVA PLA2, and COX2. In line with its anti-inflammatory properties, IL-4 was unable to induce either AA release or expression of PLA2s or COX2. IL-1β and TNF strongly increased PGE2 production, with IL-1β as the most prominent inducer. CONCLUSION Multiple PLA2 isoforms are expressed and influenced by pro-inflammatory stimuli in OA chondrocytes. Hence, several PLA2 enzymes may contribute to chondrocyte function by their upregulation and activation, and increased AA release and PGE2 production may therefore be important effectors in OA pathophysiology. PLA2 enzymes and cPLA2-IVA in particular are thus possible therapeutic targets in OA.
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Affiliation(s)
- L Leistad
- SINTEF Technology and Society, Department of Health, Norwegian University of Science and Technology, Trondheim, Norway
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Coulthard LG, Costello J, Robinson B, Shiels IA, Taylor SM, Woodruff TM. Comparative efficacy of a secretory phospholipase A2 inhibitor with conventional anti-inflammatory agents in a rat model of antigen-induced arthritis. Arthritis Res Ther 2011; 13:R42. [PMID: 21401925 PMCID: PMC3132024 DOI: 10.1186/ar3278] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 02/10/2011] [Accepted: 03/14/2011] [Indexed: 12/31/2022] Open
Abstract
Introduction Previously, secretory phospholipase A2 (sPLA2) inhibition has been used as an adjunct to conventional rheumatoid arthritis therapy in human clinical trials without significant improvement of arthritic pathology. In this study, we compared the efficacy of a potent and orally active group IIa secretory phospholipase A2 inhibitor (sPLA2I) to conventional anti-arthritic agents; infliximab, leflunomide and prednisolone, in a rat model of antigen-induced arthritis. Methods Initially, to establish efficacy and dose-response, rats were orally dosed with the sPLA2I (1 and 5 mg/kg) two days prior to arthritis induction, and then daily throughout the 14-day study period. In the second trial, rats were orally dosed with the sPLA2I (5 and 10 mg/kg/day) beginning two days after the induction of arthritis, at the peak of joint swelling. Separate groups of rats were also dosed with the tumour necrosis factor-alpha (TNF-α) inhibitor infliximab (single 3 mg/kg i.v. injection), leflunomide (10 mg/kg/day, oral) or prednisolone (1 mg/kg/day, oral) at this same time point and used as comparative treatments. Results In the pathology prevention trial, both 1 and 5 mg/kg dose groups of sPLA2I demonstrated a significant reduction in joint swelling and gait disturbances; however, only the higher 5 mg/kg dose resulted in significantly reduced histopathology scores. In the post-induction trial, rats dosed with sPLA2I showed a significant improvement in joint swelling and gait scoring, whereas none of the conventional therapeutics achieved a significant decrease in both of these two disease markers. Histopathological scoring at the end-point of the study demonstrated significantly reduced median scores in rats treated with 10 mg/kg sPLA2I and leflunomide. Conclusions The results from this study suggest a pathogenic role for sPLA2 enzymes in this model of arthritis in rats, and the potential clinical utility of sPLA2 inhibition as a safer, and more effective, alternative to conventional anti-arthritic therapeutics.
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Affiliation(s)
- Liam G Coulthard
- School of Biomedical Sciences, Research Road, University of Queensland, St, Lucia, Queensland, 4072, Australia
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Murakami M, Taketomi Y, Miki Y, Sato H, Hirabayashi T, Yamamoto K. Recent progress in phospholipase A₂ research: from cells to animals to humans. Prog Lipid Res 2010; 50:152-92. [PMID: 21185866 DOI: 10.1016/j.plipres.2010.12.001] [Citation(s) in RCA: 368] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mammalian genomes encode genes for more than 30 phospholipase A₂s (PLA₂s) or related enzymes, which are subdivided into several classes including low-molecular-weight secreted PLA₂s (sPLA₂s), Ca²+-dependent cytosolic PLA₂s (cPLA₂s), Ca²+-independent PLA₂s (iPLA₂s), platelet-activating factor acetylhydrolases (PAF-AHs), lysosomal PLA₂s, and a recently identified adipose-specific PLA. Of these, the intracellular cPLA₂ and iPLA₂ families and the extracellular sPLA₂ family are recognized as the "big three". From a general viewpoint, cPLA₂α (the prototypic cPLA₂ plays a major role in the initiation of arachidonic acid metabolism, the iPLA₂ family contributes to membrane homeostasis and energy metabolism, and the sPLA₂ family affects various biological events by modulating the extracellular phospholipid milieus. The cPLA₂ family evolved along with eicosanoid receptors when vertebrates first appeared, whereas the diverse branching of the iPLA₂ and sPLA₂ families during earlier eukaryote development suggests that they play fundamental roles in life-related processes. During the past decade, data concerning the unexplored roles of various PLA₂ enzymes in pathophysiology have emerged on the basis of studies using knockout and transgenic mice, the use of specific inhibitors, and information obtained from analysis of human diseases caused by mutations in PLA₂ genes. This review focuses on current understanding of the emerging biological functions of PLA₂s and related enzymes.
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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.
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Fèvre C, Bellenger S, Pierre AS, Minville M, Bellenger J, Gresti J, Rialland M, Narce M, Tessier C. The metabolic cascade leading to eicosanoid precursors--desaturases, elongases, and phospholipases A2--is altered in Zucker fatty rats. Biochim Biophys Acta Mol Cell Biol Lipids 2010; 1811:409-17. [PMID: 21172452 DOI: 10.1016/j.bbalip.2010.12.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 11/18/2010] [Accepted: 12/10/2010] [Indexed: 11/15/2022]
Abstract
Metabolic syndrome characterized by insulin resistance and obesity is accompanied by severe lipid metabolism perturbations and chronic low-grade inflammation. However, many unresolved questions remained regarding the regulation that underlie dyslipidemia, particularly the regulation of the metabolic cascade (synthesis and release) leading to eicosanoid precursors release. This study was undertaken to investigate the regulation of desaturases/elongases and phospholipases A(2) during the establishment of metabolic syndrome. Our results showed that delta-6 desaturase as well as elongase-6 expressions were upregulated in 3-month-old Zucker fatty rats as compared to lean littermates, independently of SREBP-1c activation. We also demonstrated for the first time an increase of liver group VII phospholipase A(2) gene expression in the obese animals together with a strong specific inhibition of type IVA and VIA phospholipases A(2). These results suggest that the regulation of unsaturated fatty acids biosynthesis and signalling cascade could contribute to the development of liver lipid dysregulation related to metabolic syndrome and may be considered as new potential targets in such pathological conditions.
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Affiliation(s)
- Cécile Fèvre
- INSERM UMR 866/Université de Bourgogne, Lipides Nutrition Cancer, Faculté des Sciences Gabriel, 6 Bd Gabriel, 21000 Dijon, France
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Bryant KJ, Bidgood MJ, Lei PW, Taberner M, Salom C, Kumar V, Lee L, Church WB, Courtenay B, Smart BP, Gelb MH, Cahill MA, Graham GG, McNeil HP, Scott KF. A bifunctional role for group IIA secreted phospholipase A2 in human rheumatoid fibroblast-like synoviocyte arachidonic acid metabolism. J Biol Chem 2010; 286:2492-503. [PMID: 21068383 DOI: 10.1074/jbc.m110.123927] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Human group IIA-secreted phospholipase A(2) (sPLA(2)-IIA) is an important regulator of cytokine-mediated inflammatory responses in both in vitro and in vivo models of rheumatoid arthritis (RA). However, treatment of RA patients with sPLA(2)-IIA inhibitors shows only transient benefit. Using an activity-impaired sPLA(2)-IIA mutant protein (H48Q), we show that up-regulation of TNF-dependent PGE(2) production and cyclooxygenase-2 (COX-2) induction by exogenous sPLA(2)-IIA in RA fibroblast-like synoviocytes (FLSs) is independent of its enzyme function. Selective cytosolic phospholipase A(2)-α (cPLA(2)-α) inhibitors abrogate TNF/sPLA(2)-IIA-mediated PGE(2) production without affecting COX-2 levels, indicating arachidonic acid (AA) flux to COX-2 occurs exclusively through TNF-mediated activation of cPLA(2)-α. Nonetheless, exogenous sPLA(2)-IIA, but not H48Q, stimulates both AA mobilization from FLSs and microparticle-derived AA release that is not used for COX-2-dependent PGE(2) production. sPLA(2)-IIA-mediated AA production is inhibited by pharmacological blockade of sPLA(2)-IIA but not cPLA(2)-α. Exogenous H48Q alone, like sPLA(2)-IIA, increases COX-2 protein levels without inducing PGE(2) production. Unlike TNF, sPLA(2)-IIA alone does not rapidly mobilize NF-κB or activate phosphorylation of p38 MAPK, two key regulators of COX-2 protein expression, but does activate the ERK1/2 pathway. Thus, sPLA(2)-IIA regulates AA flux through the cPLA(2)-α/COX-2 pathway in RA FLSs by up-regulating steady state levels of these biosynthetic enzymes through an indirect mechanism, rather than direct provision of substrate to the pathway. Inhibitors that have been optimized for their potency in enzyme activity inhibition alone may not adequately block the activity-independent function of sPLA(2)-IIA.
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Magrioti V, Kokotos G. Phospholipase A2inhibitors as potential therapeutic agents for the treatment of inflammatory diseases. Expert Opin Ther Pat 2009; 20:1-18. [DOI: 10.1517/13543770903463905] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Thwin MM, Douni E, Arjunan P, Kollias G, Kumar PV, Gopalakrishnakone P. Suppressive effect of secretory phospholipase A2 inhibitory peptide on interleukin-1beta-induced matrix metalloproteinase production in rheumatoid synovial fibroblasts, and its antiarthritic activity in hTNFtg mice. Arthritis Res Ther 2009; 11:R138. [PMID: 19765281 PMCID: PMC2787297 DOI: 10.1186/ar2810] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 09/09/2009] [Accepted: 09/18/2009] [Indexed: 01/08/2023] Open
Abstract
INTRODUCTION Secretory phospholipase A2 (sPLA2) and matrix metalloproteinase (MMP) inhibitors are potent modulators of inflammation with therapeutic potential, but have limited efficacy in rheumatoid arthritis (RA). The objective of this study was to understand the inhibitory mechanism of phospholipase inhibitor from python (PIP)-18 peptide in cultured synovial fibroblasts (SF), and to evaluate its therapeutic potential in a human tumor necrosis factor (hTNF)-driven transgenic mouse (Tg197) model of arthritis. METHODS Gene and protein expression of sPLA2-IIA, MMP-1, MMP-2, MMP-3, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-1, and TIMP-2 were analyzed by real time PCR and ELISA respectively, in interleukin (IL)-1beta stimulated rheumatoid arthritis (RA) and osteoarthritis (OA) synovial fibroblasts cells treated with or without inhibitors of sPLA2 (PIP-18, LY315920) or MMPs (MMP Inhibitor II). Phosphorylation status of mitogen-activated protein kinase (MAPK) proteins was examined by cell-based ELISA. The effect of PIP-18 was compared with that of celecoxib, methotrexate, infliximab and antiflamin-2 in Tg197 mice after ip administration (thrice weekly for 5 weeks) at two doses (10, 30 mg/kg), and histologic analysis of ankle joints. Serum sPLA2 and cytokines (tumor necrosis factor (TNF)alpha, IL-6) were measured by Escherichia coli (E coli) assay and ELISA, respectively. RESULTS PIP-18 inhibited sPLA2-IIA production and enzymatic activity, and suppressed production of MMPs in IL-1beta-induced RA and OA SF cells. Treatment with PIP-18 blocked IL-1beta-induced p38 MAPK phosphorylation and resulted in attenuation of sPLA2-IIA and MMP mRNA transcription in RA SF cells. The disease modifying effect of PIP-18 was evidenced by significant abrogation of synovitis, cartilage degradation and bone erosion in hTNF Tg197 mice. CONCLUSIONS Our results demonstrate the benefit that can be gained from using sPLA2 inhibitory peptide for RA treatment, and validate PIP-18 as a potential therapeutic in a clinically relevant animal model of human arthritis.
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Affiliation(s)
- Maung-Maung Thwin
- Department of Anatomy, Yong Loo Lin School of Medicine, 4 Medical Drive, National University of Singapore, 117597 Singapore.
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Abstract
Introduction The secretory phospholipase A2 (sPLA2) family provides a seemingly endless array of potential biological functions that is only beginning to be appreciated. In humans, this family comprises 9 different members that vary in their tissue distribution, hydrolytic activity, and phospholipid substrate specificity. Through their lipase activity, these enzymes trigger various cell-signaling events to regulate cellular functions, directly kill bacteria, or modulate inflammatory responses. In addition, some sPLA2’s are high affinity ligands for cellular receptors. Objective This review merely scratches the surface of some of the actions of sPLA2s in innate immunity, inflammation, and atherosclerosis. The goal is to provide an overview of recent findings involving sPLA2s and to point to potential pathophysiologic mechanisms that may become targets for therapy.
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Aquino M, Guerrero MD, Bruno I, Terencio MC, Paya M, Riccio R. Development of a second generation of inhibitors of microsomal prostaglandin E synthase 1 expression bearing the γ-hydroxybutenolide scaffold. Bioorg Med Chem 2008; 16:9056-64. [DOI: 10.1016/j.bmc.2008.08.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Revised: 07/31/2008] [Accepted: 08/01/2008] [Indexed: 10/21/2022]
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Thwin MM, Satyanarayanajois SD, Nagarajarao LM, Sato K, Arjunan P, Ramapatna SL, Kumar PV, Gopalakrishnakone P. Novel Peptide Inhibitors of Human Secretory Phospholipase A2 with Antiinflammatory Activity: Solution Structure and Molecular Modeling. J Med Chem 2007; 50:5938-50. [DOI: 10.1021/jm070385x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Liu Z, Lu X, Wang H, You XJ, Gao QX, Cui YH. Group II subfamily secretory phospholipase A2 enzymes: expression in chronic rhinosinusitis with and without nasal polyps. Allergy 2007; 62:999-1006. [PMID: 17578498 DOI: 10.1111/j.1398-9995.2007.01381.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND Group II subfamily secretory phospholipases A(2) (sPLA(2)s) are the enzymes that can play a major role in inflammation. However, the presence of group II subfamily sPLA(2)s in human sinonasal mucosa and their roles in chronic rhinosinusitis (CRS) are not well known. The purpose of this study was to investigate the expression of group II subfamily sPLA(2)s in human sinonasal mucosa from controls and CRS patients with and without nasal polyps (NPs) and the regulation of expression by proinflammatory cytokines. METHODS Surgical samples were investigated by means of reverse transcriptase polymerase chain reaction (RT-PCR) for evaluation of group II subfamily sPLA(2)s mRNA expression, and the presence and location of group II subfamily sPLA(2)s-positive cells were analyzed by means of immunohistochemistry. Furthermore, nasal explant culture and quantitative RT-PCR techniques were used to investigate the effect of interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha on group II subfamily sPLA(2)s mRNA production in sinonasal mucosa. RESULTS Messenger RNA expression of sPLA(2)-IIA, -IID, and -IIE was significantly upregulated in tissues from CRS patients compared with control tissues. Among CRS patients, patients without NPs showed significantly stronger expression in sinonasal mucosa than patients with NPs of sPLA(2)-IIA mRNA, and weaker expression of sPLA(2)-IIE mRNA. Immunohistochemistry revealed enhanced protein expression of type II sPLA(2)s and specific type IIA sPLA(2) in epithelial cells and submucosal glands in samples from CRS patients. Stronger type IIA sPLA(2) protein expression was found in samples from CRS patients without NPs when compared with NPs. Nasal explant culture experiments demonstrated that mRNA expression of sPLA(2)-IIA, -IID, and -IIE was dramatically induced by IL-1beta and TNF-alpha. CONCLUSIONS The expression of some members of group II subfamily of sPLA(2)s is upregulated in CRS and it may result from IL-1beta and TNF-alpha overexpression. Different individual group II subfamily sPLA(2)s may play different roles in the pathogenesis of CRS with and without NPs.
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Affiliation(s)
- Z Liu
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Guerrero MD, Aquino M, Bruno I, Terencio MC, Paya M, Riccio R, Gomez-Paloma L. Synthesis and Pharmacological Evaluation of a Selected Library of New Potential Anti-inflammatory Agents Bearing the γ-Hydroxybutenolide Scaffold: a New Class of Inhibitors of Prostanoid Production through the Selective Modulation of Microsomal Prostaglandin E Synthase-1 Expression. J Med Chem 2007; 50:2176-84. [PMID: 17407277 DOI: 10.1021/jm0700823] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As a part of our drug discovery effort, recently we clarified the molecular basis of phospholipase A2 (PLA2) inactivation by petrosaspongiolide M (PM), an interesting metabolite belonging to a marine sesterterpene family, containing in its structural architecture a gamma-hydroxybutenolide moiety and showing potent anti-inflammatory activity. In the attempt to expand structural diversity as well as to simplify crucial synthetic features of the parent compound, we decided to develop a selected library based on the densely functionalized gamma-hydroxybutenolide scaffold. The synthesized products were tested for their ability to inhibit PLA2 enzymes as well as to modulate the expression of inducible cyclooxygenase 2 (COX-2) and microsomal prostaglandin E synthase 1 (mPGES-1), two key enzymes highly involved in the inflammatory event, in order to discover new promising anti-inflammatory agents with better pharmacological profiles. This led us to the discovery of a promising inhibitor (4e) of prostanoid production acting by in vitro and in vivo selective modulation of microsomal prostaglandin E synthase 1 expression.
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Affiliation(s)
- Maria D Guerrero
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Salerno, Via Ponte Don Melillo, 84084 Fisciano (SA), Italy
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Kimura-Matsumoto M, Ishikawa Y, Komiyama K, Tsuruta T, Murakami M, Masuda S, Akasaka Y, Ito K, Ishiguro S, Morita H, Sato S, Ishii T. Expression of secretory phospholipase A2s in human atherosclerosis development. Atherosclerosis 2007; 196:81-91. [PMID: 17353016 DOI: 10.1016/j.atherosclerosis.2006.08.062] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2005] [Revised: 05/24/2006] [Accepted: 08/04/2006] [Indexed: 11/27/2022]
Abstract
Secretory phospholipase A2s (sPLA2s) contribute to the hydrolysis of phospholipid. Among them, sPLA2-IIA, -V, and -X have been regarded as enhancers of lipid accumulation in arterial intima. However, the distribution and production of the other types of sPLA2 in human aortic wall remain unclear. Therefore, in this study, the distribution and production of seven types of sPLA2 including IIA, IID, IIE, IIF, III, V, and X in atherosclerosis development in the human aorta were comprehensively examined by immunohistochemistry and in situ hybridization (ISH). The extent of sPLA2s expression increased with atherosclerosis development, but only sPLA2-IIF was never observed in the normal aorta. Double-immunostaining demonstrated that sPLA2-V expression was limited to smooth muscle cells (SMCs), although the other sPLA2s were expressed in both macrophages and SMCs. ISH using sPLA2 cDNAs revealed that the expression pattern of each mRNA was consistent with the results of immunohistochemistry for each corresponding sPLA2. These results indicate that the seven types of sPLA2 are expressed with various patterns in all stages of atherosclerosis development and may play an atherogenic role through degradation of phospholipid.
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Affiliation(s)
- Masayo Kimura-Matsumoto
- Department of Pathology, Toho University, School of Medicine, 5-21-16 Ohmori-nishi, Ohta-ku, Tokyo 143-8540, Japan.
| | - Yukio Ishikawa
- Department of Pathology, Toho University, School of Medicine, 5-21-16 Ohmori-nishi, Ohta-ku, Tokyo 143-8540, Japan
| | | | | | - Makoto Murakami
- Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan; Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, Tokyo, Japan; Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, Saitama, Japan
| | - Seiko Masuda
- Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, Tokyo, Japan
| | - Yoshikiyo Akasaka
- Department of Pathology, Toho University, School of Medicine, 5-21-16 Ohmori-nishi, Ohta-ku, Tokyo 143-8540, Japan
| | - Kinji Ito
- Department of Pathology, Toho University, School of Medicine, 5-21-16 Ohmori-nishi, Ohta-ku, Tokyo 143-8540, Japan
| | - Shigeki Ishiguro
- Department of Pathology, Toho University, School of Medicine, 5-21-16 Ohmori-nishi, Ohta-ku, Tokyo 143-8540, Japan
| | - Hiroshi Morita
- Department of Gastroenterology and Hepatology, Toho University Ohmori Medical Center, Tokyo, Japan
| | - Shinji Sato
- Department of Gastroenterology and Hepatology, Toho University Ohmori Medical Center, Tokyo, Japan
| | - Toshiharu Ishii
- Department of Pathology, Toho University, School of Medicine, 5-21-16 Ohmori-nishi, Ohta-ku, Tokyo 143-8540, Japan
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Sheibanie AF, Khayrullina T, Safadi FF, Ganea D. Prostaglandin E2 exacerbates collagen-induced arthritis in mice through the inflammatory interleukin-23/interleukin-17 axis. ACTA ACUST UNITED AC 2007; 56:2608-19. [PMID: 17665454 DOI: 10.1002/art.22794] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Recently, Th17 cells, a new subset of CD4+ T cells, emerged as major players in inflammation/autoimmunity. Maintenance of the Th17 phenotype requires interleukin-23 (IL-23), whereas the Th1-promoting cytokine IL-12p70 exerts a negative effect on Th17 cell differentiation. The lipid mediator prostaglandin E(2) (PGE(2)) acts primarily as a proinflammatory agent in autoimmune conditions, through mechanisms that remain to be elucidated. The aim of this study was to investigate whether PGE(2) released in inflammatory foci activates resident dendritic cells (DCs) to express IL-23 (at the expense of IL-12) and IL-6, resulting in a shift toward Th17 cell responses. METHODS The effect of PGE(2) on IL-23 production by DCs and subsequent induction of T cell-derived IL-17 was assessed in vitro and in vivo. The effect of the stable PGE analog misoprostol was evaluated in a murine model of rheumatoid arthritis, in conjunction with IL-23 and IL-17 expression in affected joints and draining lymph nodes. RESULTS In vivo administration of PGE(2) induced IL-23-dependent IL-17 production. Administration of misoprostol exacerbated collagen-induced arthritis (CIA). CIA exacerbation was associated with increased levels of IL-23p19/p40 messenger RNA and reduced expression of IL-12p35, and with increased levels of the proinflammatory cytokines IL-17, IL-1beta, IL-6, and tumor necrosis factor in the affected joint. Following ex vivo restimulation, draining lymph node cells from misoprostol-treated mice secreted higher levels of IL-17 and lower levels of interferon-gamma. CONCLUSION Our results indicate that PGE(2) enhances DC-derived IL-6 production and induces a shift in the IL-23/IL-12 balance in favor of IL-23, resulting in increased IL-17 production, presumably through the amplification of self-reactive Th17 cells.
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Affiliation(s)
- Amir F Sheibanie
- Department of Physiology, Temple University School of Medicine, 3420 North Broad Street, Philadelphia, PA 19140, USA
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Yedgar S, Cohen Y, Shoseyov D. Control of phospholipase A2 activities for the treatment of inflammatory conditions. Biochim Biophys Acta Mol Cell Biol Lipids 2006; 1761:1373-82. [PMID: 16978919 DOI: 10.1016/j.bbalip.2006.08.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Accepted: 08/01/2006] [Indexed: 01/10/2023]
Abstract
Phospholipase-A2 (PLA2) enzymes hydrolyze cell membrane phospholipids to produce arachidonic acid (AA) and lyso-phospholipids (LysoPL), playing a key role in the production of inflammatory lipid mediators, mainly eicosanoids. They are therefore considered pro-inflammatory enzymes and their inhibition has long been recognized as a desirable therapeutic target. However, attempts to develop suitable PLA2 inhibitors for the treatment of inflammatory diseases have yet to succeed. This is due to their functional and structural diversity, and their homeostatic and even anti-inflammatory roles in certain circumstances. In the present review we outline the diversity and functions of PLA2 isoforms, and their interplay in the induction and inhibition of inflammatory processes, with emphasis on discussing approaches for therapeutic manipulation of PLA2 activities.
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Affiliation(s)
- Saul Yedgar
- Department of Biochemistry, Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel.
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Triggiani M, Granata F, Frattini A, Marone G. Activation of human inflammatory cells by secreted phospholipases A2. Biochim Biophys Acta Mol Cell Biol Lipids 2006; 1761:1289-300. [PMID: 16952481 DOI: 10.1016/j.bbalip.2006.07.003] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2006] [Revised: 07/07/2006] [Accepted: 07/17/2006] [Indexed: 10/24/2022]
Abstract
Secreted phospholipases A(2) (sPLA(2)s) are enzymes detected in serum and biological fluids of patients with various inflammatory, autoimmune and allergic disorders. Different isoforms of sPLA(2)s are expressed and released by human inflammatory cells, such as neutrophils, eosinophils, T cells, monocytes, macrophages and mast cells. sPLA(2)s generate arachidonic acid and lysophospholipids thus contributing to the production of bioactive lipid mediators in inflammatory cells. However, sPLA(2)s also activate human inflammatory cells by mechanisms unrelated to their enzymatic activity. Several human and non-human sPLA(2)s induce degranulation of mast cells, neutrophils and eosinophils and activate exocytosis in macrophages. In addition some, but not all, sPLA(2) isoforms promote cytokine and chemokine production from macrophages, neutrophils, eosinophils, monocytes and endothelial cells. These effects are primarily mediated by binding of sPLA(2)s to specific membrane targets (heparan sulfate proteoglycans, M-type, N-type or mannose receptors) expressed on effector cells. Thus, sPLA(2)s may play an important role in the initiation and amplification of inflammatory reactions by at least two mechanisms: production of lipid mediators and direct activation of inflammatory cells. Selective inhibitors of sPLA(2)-enzymatic activity and specific antagonists of sPLA(2) receptors are current being tested for pharmacological treatment of inflammatory and autoimmune diseases.
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Affiliation(s)
- Massimo Triggiani
- Division of Clinical Immunology and Allergy, Center for Basic and Clinical Immunology Research (CISI), University of Naples Federico II, 80131 Naples, Via Pansini 5, Italy.
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Mitsuishi M, Masuda S, Kudo I, Murakami M. Group V and X secretory phospholipase A2 prevents adenoviral infection in mammalian cells. Biochem J 2006; 393:97-106. [PMID: 16146426 PMCID: PMC1383668 DOI: 10.1042/bj20050781] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
sPLA2 (secretory phospholipase A2) enzymes have been implicated in various biological events, yet their precise physiological functions remain largely unresolved. In the present study we show that group V and X sPLA2s, which are two potent plasma membrane-acting sPLA2s, are capable of preventing host cells from being infected with an adenovirus. Bronchial epithelial cells and lung fibroblasts pre-expressing group V and X sPLA2s showed marked resistance to adenovirus-mediated gene delivery in a manner dependent on their catalytic activity. Although adenovirus particles were insensitive to recombinant group V and X sPLA2s, direct addition of these enzymes to 293A cells suppressed both number and size of adenovirus plaque formation. Group V and X sPLA2s retarded the entry of adenovirus into endosomes. Moreover, adenoviral infection was suppressed by LPC (lysophosphatidylcholine), a membrane-hydrolytic product of these sPLA2s. Thus hydrolysis of the plasma membrane by these sPLA2s may eventually lead to the protection of host cells from adenovirus entry. Given that group V and X sPLA2s are expressed in human airway epithelium and macrophages and that the expression of endogenous group V sPLA2 is upregulated by virus-related stimuli in these cells, our present results raise the possibility that group V and X sPLA2s may play a role in innate immunity against adenoviral infection in the respiratory tract.
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Affiliation(s)
- Michiko Mitsuishi
- *Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Seiko Masuda
- *Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Ichiro Kudo
- *Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Makoto Murakami
- *Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
- †Tokyo Metropolitan Institute of Medical Science, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo 113-8613, Japan
- To whom correspondence should be addressed (email )
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Qin S, Pande AH, Nemec KN, He X, Tatulian SA. Evidence for the Regulatory Role of the N-terminal Helix of Secretory Phospholipase A2 from Studies on Native and Chimeric Proteins. J Biol Chem 2005; 280:36773-83. [PMID: 16103116 DOI: 10.1074/jbc.m506789200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The phospholipase A(2) (PLA(2)) enzymes are activated by binding to phospholipid membranes. Although the N-terminal alpha-helix of group I/II PLA(2)s plays an important role in the productive mode membrane binding of the enzymes, its role in the structural aspects of membrane-induced activation of PLA(2)s is not well understood. In order to elucidate membrane-induced conformational changes in the N-terminal helix and in the rest of the PLA(2), we have created semisynthetic human group IB PLA(2) in which the N-terminal decapeptide is joined with the (13)C-labeled fragment, as well as a chimeric protein containing the N-terminal decapeptide from human group IIA PLA(2) joined with a (13)C-labeled fragment of group IB PLA(2). Infrared spectral resolution of the unlabeled and (13)C-labeled segments suggests that the N-terminal helix of membrane-bound IB PLA(2) has a more rigid structure than the other helices. On the other hand, the overall structure of the chimeric PLA(2) is more rigid than that of the IB PLA(2), but the N-terminal helix is more flexible. A combination of homology modeling and polarized infrared spectroscopy provides the structure of membrane-bound chimeric PLA(2), which demonstrates remarkable similarity but also distinct differences compared with that of IB PLA(2). Correlation is delineated between structural and membrane binding properties of PLA(2)s and their N-terminal helices. Altogether, the data provide evidence that the N-terminal helix of group I/II PLA(2)s acts as a regulatory domain that mediates interfacial activation of these enzymes.
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Affiliation(s)
- Shan Qin
- Biomolecular Science Center, University of Central Florida, Orlando, Florida 32826, USA
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Triggiani M, Granata F, Giannattasio G, Marone G. Secretory phospholipases A2 in inflammatory and allergic diseases: not just enzymes. J Allergy Clin Immunol 2005; 116:1000-6. [PMID: 16275367 DOI: 10.1016/j.jaci.2005.08.011] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Revised: 08/04/2005] [Accepted: 08/08/2005] [Indexed: 12/30/2022]
Abstract
Secretory phospholipases A(2) (sPLA(2)s) are molecules released in plasma and biologic fluids of patients with systemic inflammatory, autoimmune, and allergic diseases. Several sPLA(2) isoforms are expressed and released by such human inflammatory cells as neutrophils, eosinophils, basophils, T cells, monocytes, macrophages, and mast cells. Certain sPLA(2)s release arachidonic acid, thereby providing the substrate for the biosynthesis of proinflammatory eicosanoids. However, there are other mechanisms by which sPLA(2)s might participate in the synthesis of lipid mediators. Interestingly, sPLA(2)s activate inflammatory cells through mechanisms unrelated to their enzymatic activity. Several sPLA(2)s induce degranulation of mast cells and eosinophils and activate exocytosis in macrophages. Furthermore, sPLA(2)s promote cytokine and chemokine production from macrophages, neutrophils, eosinophils, monocytes, and endothelial cells. Some of these effects are mediated by the binding of sPLA(2)s to specific receptors expressed on effector cells. Thus sPLA(2)s might play important roles in the initiation and amplification of the inflammatory reaction. Selective inhibitors of sPLA(2)s and specific antagonists of sPLA(2) receptors might prove useful in the treatment of allergic and autoimmune diseases, such as bronchial asthma and rheumatoid arthritis.
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Affiliation(s)
- Massimo Triggiani
- Division of Clinical Immunology and Allergy, Center for Basic and Clinical Immunology Research (CISI), University of Naples Federico II, Naples, Italy
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Masuda S, Murakami M, Ishikawa Y, Ishii T, Kudo I. Diverse cellular localizations of secretory phospholipase A2 enzymes in several human tissues. Biochim Biophys Acta Mol Cell Biol Lipids 2005; 1736:200-10. [PMID: 16188494 DOI: 10.1016/j.bbalip.2005.08.014] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Revised: 07/30/2005] [Accepted: 08/02/2005] [Indexed: 01/07/2023]
Abstract
The secretory phospholipase A2 (sPLA2) family in mammals contains more than 10 enzymes. In this study, we examined by immunohistochemistry the localization of six sPLA2s (IIA, IID, IIE, IIF, V and X) in human heart, kidney, liver and stomach. In normal hearts, sPLA2-IIA was detected in coronary vascular smooth muscle cells (VSMC) and sPLA2-V in cardiomyocytes beneath the endocardium. In infarcted hearts, expression of these two enzymes was markedly increased in damaged cardiomyocytes, and expression of sPLA2-IID and-IIE, which was undetectable in normal hearts, was elevated in damaged cardiomyocytes and VSMC, respectively. In infarcted kidneys, sPLA2-IIA and-V were markedly induced in the uriniferous tubular epithelium. In livers affected by viral hepatitis, sPLA2-IIA and-V were expressed in hepatocytes with fatty degeneration. In the gastric glands exhibiting intestinal metaplasia, sPLA2-IIA was localized in the glandular base, sPLA2-IID and-V in the glandular body epithelium, sPLA2-IIE and-IIF in goblet cells in the foveolar epithelium, and sPLA2-X in both glandular body epithelial cells and foveolar epithelial goblet cells. In the gastric submucosal tissues, sPLA2-IIA and-IIE were located in VSMC and sPLA2-V was in the interstitial fibroblasts. In addition, sPLA2-IIA,-IIE,-IIF and-X were highly expressed in gastric signet ring cell carcinoma. Thus, individual sPLA2s exhibit unique cellular localizations in each tissue, suggesting their distinct roles in pathophysiology.
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Affiliation(s)
- Seiko Masuda
- Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
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Masuda S, Murakami M, Mitsuishi M, Komiyama K, Ishikawa Y, Ishii T, Kudo I. Expression of secretory phospholipase A2 enzymes in lungs of humans with pneumonia and their potential prostaglandin-synthetic function in human lung-derived cells. Biochem J 2005; 387:27-38. [PMID: 15509193 PMCID: PMC1134929 DOI: 10.1042/bj20041307] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Although a number of sPLA2 (secretory phospholipase A2) enzymes have been identified in mammals, the localization and functions of individual enzymes in human pathologic tissues still remain obscure. In the present study, we have examined the expression and function of sPLA2s in human lung-derived cells and in human lungs with pneumonia. Group IID, V and X sPLA2s were expressed in cultured human bronchial epithelial cells (BEAS-2B) and normal human pulmonary fibroblasts with distinct requirement for cytokines (interleukin-1b, tumour necrosis factor a and interferon-g). Lentivirus- or adenovirus-mediated transfection of various sPLA2s into BEAS-2B or normal human pulmonary fibroblast cells revealed that group V and X sPLA2s increased arachidonate release and prostaglandin production in both cell types, whereas group IIA and IID sPLA2s failed to do so. Immunohistochemistry of human lungs with pneumonia demonstrated that group V and X sPLA2s were widely expressed in the airway epithelium, interstitium and alveolar macrophages, in which group IID sPLA2 was also positive, whereas group IIA sPLA2 was restricted to the pulmonary arterial smooth muscle layers and bronchial chondrocytes, and group IIE and IIF sPLA2s were minimally detected. These results suggest that group V and X sPLA2s affect lung pathogenesis by facilitating arachidonate metabolism or possibly through other functions.
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Affiliation(s)
- Seiko Masuda
- *Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Makoto Murakami
- *Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
- To whom correspondence should be addressed (email )
| | - Michiko Mitsuishi
- *Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Kazuo Komiyama
- †Department of Pathology, Division of Immunology and Patho-Biology at Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Yukio Ishikawa
- ‡Department of Pathology, Toho University, School of Medicine, 5-21-16 Omori-Nishi, Ohta-ku, Tokyo 143-8540, Japan
| | - Toshiharu Ishii
- ‡Department of Pathology, Toho University, School of Medicine, 5-21-16 Omori-Nishi, Ohta-ku, Tokyo 143-8540, Japan
| | - Ichiro Kudo
- *Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
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Murakami M, Masuda S, Shimbara S, Ishikawa Y, Ishii T, Kudo I. Cellular Distribution, Post-translational Modification, and Tumorigenic Potential of Human Group III Secreted Phospholipase A2. J Biol Chem 2005; 280:24987-98. [PMID: 15863501 DOI: 10.1074/jbc.m502088200] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Human group III secreted phospholipase A(2) (sPLA(2)-III) consists of a central group III sPLA(2) domain flanked by unique N- and C-terminal domains. We found that the sPLA(2) domain alone was sufficient for its catalytic activity and for its prostaglandin E(2) (PGE(2))-generating functions in various cell types. In several if not all cell types, the N- and C-terminal domains of sPLA(2)-III were proteolytically removed, leading to the production of the form containing only the sPLA(2) domain, which could be further N-glycosylated at two consensus sites. Immunohistochemistry demonstrated that sPLA(2)-III was preferentially expressed in the microvascular endothelium in human tissues with inflammation, ischemic injury, and cancer. In support of this, sPLA(2)-III was induced in cultured microvascular endothelial cells after stimulation with proinflammatory cytokines. Expression of sPLA(2)-III was also associated with various tumor cells, and colorectal cancer cells transfected with sPLA(2)-III exhibited enhanced PGE(2) production and cell proliferation, which required sPLA(2)-III catalytic activity. When implanted into nude mice, the sPLA(2)-III-transfected cells formed larger solid tumors with increased angiogenesis compared with control cells. Moreover, small interfering RNA for sPLA(2)-III significantly reduced PGE(2) production and proliferation of colorectal cancer cells. Taken together, these results reveal unique cell type-specific processing and N-glycosylation of sPLA(2)-III and the potential role of this enzyme in cancer development by stimulating tumor cell growth and angiogenesis.
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MESH Headings
- Adenoviridae/genetics
- Amino Acid Sequence
- Animals
- Arachidonic Acid/chemistry
- Arthritis, Rheumatoid/pathology
- Blotting, Northern
- Catalytic Domain
- Cell Line
- Cell Line, Tumor
- Cell Proliferation
- Colorectal Neoplasms/pathology
- Dose-Response Relationship, Drug
- Endothelium, Vascular/cytology
- Female
- Fibroblasts/metabolism
- Gene Expression Regulation, Neoplastic
- Glycoside Hydrolases/metabolism
- Glycosylation
- Group III Phospholipases A2
- Humans
- Immunohistochemistry
- Inflammation
- Ischemia/pathology
- Lentivirus/metabolism
- Lung/pathology
- Mice
- Mice, Nude
- Microcirculation
- Microscopy, Confocal
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Neovascularization, Pathologic
- Phospholipases A/chemistry
- Phospholipases A/physiology
- Point Mutation
- Prostaglandins/chemistry
- Protein Processing, Post-Translational
- Protein Structure, Tertiary
- Reverse Transcriptase Polymerase Chain Reaction
- Time Factors
- Uterine Neoplasms/pathology
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Affiliation(s)
- Makoto Murakami
- Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.
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Masuda S, Murakami M, Takanezawa Y, Aoki J, Arai H, Ishikawa Y, Ishii T, Arioka M, Kudo I. Neuronal Expression and Neuritogenic Action of Group X Secreted Phospholipase A2. J Biol Chem 2005; 280:23203-14. [PMID: 15781456 DOI: 10.1074/jbc.m500985200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although individual mammalian secreted phospholipase A(2) (sPLA(2)) enzymes exhibit unique tissue and cellular distributions, the cell type-specific functions of each enzyme remain largely unknown. In this study, we found by immunohistochemistry that group X sPLA(2) (sPLA(2)-X) is uniquely located in the peripheral neuronal fibers, an observation that was supported by detection of its transcript and protein in the neuronal cell line PC12 and in primary dorsal root ganglia neurons. Adenoviral expression of sPLA(2)-X in PC12 cells facilitated neurite outgrowth, particularly when combined with a suboptimal concentration of nerve growth factor. In neuronally differentiated PC12 cells, sPLA(2)-X was preferentially localized in the Golgi apparatus and growth cones, and proteolytic conversion of the proenzyme to mature enzyme mainly occurred after the secretion process. The neurite-extending ability of sPLA(2)-X depended on the production of its catalytic product, lysophosphatidylcholine. Moreover, nerve growth factor-induced neurite extension of PC12 cells was modestly but significantly attenuated by an anti-sPLA(2)-X antibody or by a small interfering RNA for sPLA(2)-X. These observations suggest the potential contribution of sPLA(2)-X to neuronal differentiation, and possibly repair, under certain conditions.
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Affiliation(s)
- Seiko Masuda
- Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, Shinagawa-ku, Tokyo, USA
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