1
|
The phospholipase A 2 superfamily as a central hub of bioactive lipids and beyond. Pharmacol Ther 2023; 244:108382. [PMID: 36918102 DOI: 10.1016/j.pharmthera.2023.108382] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 03/13/2023]
Abstract
In essence, "phospholipase A2" (PLA2) means a group of enzymes that release fatty acids and lysophospholipids by hydrolyzing the sn-2 position of glycerophospholipids. To date, more than 50 enzymes possessing PLA2 or related lipid-metabolizing activities have been identified in mammals, and these are subdivided into several families in terms of their structures, catalytic mechanisms, tissue/cellular localizations, and evolutionary relationships. From a general viewpoint, the PLA2 superfamily has mainly been implicated in signal transduction, driving the production of a wide variety of bioactive lipid mediators. However, a growing body of evidence indicates that PLA2s also contribute to phospholipid remodeling or recycling for membrane homeostasis, fatty acid β-oxidation for energy production, and barrier lipid formation on the body surface. Accordingly, PLA2 enzymes are considered one of the key regulators of a broad range of lipid metabolism, and perturbation of specific PLA2-driven lipid pathways often disrupts tissue and cellular homeostasis and may be associated with a variety of diseases. This review covers current understanding of the physiological functions of the PLA2 superfamily, focusing particularly on the two major intracellular PLA2 families (Ca2+-dependent cytosolic PLA2s and Ca2+-independent patatin-like PLA2s) as well as other PLA2 families, based on studies using gene-manipulated mice and human diseases in combination with comprehensive lipidomics.
Collapse
|
2
|
dos Santos HT, Nam K, Gil D, Yellepeddi V, Baker OJ. Current experimental methods to investigate the impact of specialized pro-resolving lipid mediators on Sjögren's syndrome. Front Immunol 2023; 13:1094278. [PMID: 36713415 PMCID: PMC9878840 DOI: 10.3389/fimmu.2022.1094278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 12/27/2022] [Indexed: 01/15/2023] Open
Abstract
Sjögren's syndrome is a chronic inflammatory autoimmune disease characterized by diminished secretory function of the exocrine glands. Although extensive investigation has been done to understand Sjögren's syndrome, the causes of the disease are as yet unknown and treatments remain largely ineffective, with established therapeutic interventions being limited to use of saliva substitutes with modest effectiveness. A primary feature of Sjögren's syndrome is uncontrolled inflammation of exocrine tissues and previous studies have demonstrated that lipid-based specialized pro-resolving mediators reduce inflammation and restores tissue integrity in salivary glands. However, these studies are limited to a single specialized pro-resolving lipid mediator's family member resolvin D1 or RvD1 and its aspirin-triggered epimer, AT-RvD1. Consequently, additional studies are needed to explore the potential benefits of other members of the specialized pro-resolving lipid mediator's family and related molecules (e.g., additional resolvin subtypes as well as lipoxins, maresins and protectins). In support of this goal, the current review aims to briefly describe the range of current experimental methods to investigate the impact of specialized pro-resolving lipid mediators on Sjögren's syndrome, including both strengths and weaknesses of each approach where this information is known. With this article, the possibilities presented by specialized pro-resolving lipid mediators will be introduced to a wider audience in immunology and practical advice is given to researchers who may wish to take up this work.
Collapse
Affiliation(s)
- Harim T. dos Santos
- Bond Life Sciences Center, University of Missouri, Columbia, MO, United States,Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Missouri, Columbia, MO, United States
| | - Kihoon Nam
- Bond Life Sciences Center, University of Missouri, Columbia, MO, United States,Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Missouri, Columbia, MO, United States
| | - Diana Gil
- Department of Surgery, School of Medicine, University of Missouri, Columbia, MO, United States,Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO, United States,Department of Biological and Biomedical Engineering, College of Engineering, University of Missouri, Columbia, MO, United States
| | - Venkata Yellepeddi
- Division of Clinical Pharmacology, Department of Pediatrics, School of Medicine, University of Utah, Salt Lake City, UT, United States,Department of Molecular Pharmaceutics, College of Pharmacy, University of Utah, Salt Lake City, UT, United States
| | - Olga J. Baker
- Bond Life Sciences Center, University of Missouri, Columbia, MO, United States,Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Missouri, Columbia, MO, United States,Department of Biochemistry, University of Missouri, Columbia, MO, United States,*Correspondence: Olga J. Baker,
| |
Collapse
|
3
|
Hashimoto M, Makino N, Inazumi T, Yoshida R, Sugimoto T, Tsuchiya S, Sugimoto Y. Effects of an ω3 fatty acid-biased diet on luteolysis, parturition, and uterine prostanoid synthesis in pregnant mice. Biochem Biophys Res Commun 2022; 589:139-146. [PMID: 34920379 DOI: 10.1016/j.bbrc.2021.12.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 11/16/2022]
Abstract
The ω3 polyunsaturated fatty acids (PUFAs) are known to have beneficial effects on health and diseases, and hence their intake is encouraged. However, it remains unknown as to how ω3 PUFAs affect female reproduction processes, in which ω6 PUFA-derived prostaglandin (PG) E2 and PGF2α play crucial roles. We therefore compared female reproductive performance between ω3 PUFA-biased linseed oil diet-fed (Lin) mice and ω6 PUFA-biased soybean oil diet-fed (Soy) mice. In Lin mice, the uterine levels of arachidonic acid (AA) and eicosapentaenoic acid (EPA) were 0.42 fold and 16 fold of those in Soy mice, respectively, with the EPA/AA ratio being 0.7 (vs 0.02 in Soy mice). Lin mice showed no alterations in any of the fertility indexes, including luteolysis and parturition. The uterine PG synthesis profiles of Lin mice were similar to those of Soy mice, but the levels of PGF2α and PGE2 were 50% of those in Soy mice, as a result of the increased EPA/AA ratio. PGF3α and PGE3 were undetectable in the uterine tissues of Soy and Lin mice. Interestingly, in Lin mice, 'luteolytic' PGF2α synthesis was considerably maintained even in the ω6 PUFA-reduced condition. These results suggest the existence of an elaborate mechanism securing PGF2α synthesis to a level that is sufficient for triggering luteolysis and parturition, even under ω6 PUFA-reduced conditions.
Collapse
Affiliation(s)
- Miho Hashimoto
- Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, 862-0973, Japan
| | - Nagisa Makino
- Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, 862-0973, Japan
| | - Tomoaki Inazumi
- Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, 862-0973, Japan
| | - Rina Yoshida
- Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, 862-0973, Japan
| | - Toshiko Sugimoto
- Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, 862-0973, Japan
| | - Soken Tsuchiya
- Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, 862-0973, Japan
| | - Yukihiko Sugimoto
- Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, 862-0973, Japan.
| |
Collapse
|
4
|
Hayashi D, Mouchlis VD, Dennis EA. Omega-3 versus Omega-6 fatty acid availability is controlled by hydrophobic site geometries of phospholipase A 2s. J Lipid Res 2021; 62:100113. [PMID: 34474084 PMCID: PMC8551542 DOI: 10.1016/j.jlr.2021.100113] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 08/24/2021] [Accepted: 08/27/2021] [Indexed: 11/12/2022] Open
Abstract
Human phospholipase A2s (PLA2) constitute a superfamily of enzymes that hydrolyze the sn-2 acyl-chain of glycerophospholipids, producing lysophospholipids and free fatty acids. Each PLA2 enzyme type contributes to specific biological functions based on its expression, subcellular localization, and substrate specificity. Among the PLA2 superfamily, the cytosolic cPLA2 enzymes, calcium-independent iPLA2 enzymes, and secreted sPLA2 enzymes are implicated in many diseases, but a central issue is the preference for double-bond positions in polyunsaturated fatty acids (PUFAs) occupying the sn-2 position of membrane phospholipids. We demonstrate that each PLA2 has a unique preference between the specific omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the omega-6 arachidonic acid (AA), which are the precursors of most proinflammatory and anti-inflammatory or resolving eicosanoids and related oxylipins. Surprisingly, we discovered that human cPLA2 selectively prefers AA, whereas iPLA2 prefers EPA, and sPLA2 prefers DHA as substrate. We determined the optimal binding of each phospholipid substrate in the active site of each PLA2 to explain these specificities. To investigate this, we utilized recently developed lipidomics-based LC-MS/MS and GC/MS assays to determine the sn-2 acyl chain specificity in mixtures of phospholipids. We performed μs timescale molecular dynamics (MD) simulations to reveal unique active site properties, especially how the precise hydrophobic cavity accommodation of the sn-2 acyl chain contributes to the stability of substrate binding and the specificity of each PLA2 for AA, EPA, or DHA. This study provides the first comprehensive picture of the unique substrate selectivity of each PLA2 for omega-3 and omega-6 fatty acids.
Collapse
Affiliation(s)
- Daiki Hayashi
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Varnavas D Mouchlis
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Edward A Dennis
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, CA, USA.
| |
Collapse
|
5
|
Garić D, Dumut DC, Shah J, De Sanctis JB, Radzioch D. The role of essential fatty acids in cystic fibrosis and normalizing effect of fenretinide. Cell Mol Life Sci 2020; 77:4255-4267. [PMID: 32394023 PMCID: PMC11105061 DOI: 10.1007/s00018-020-03530-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 02/28/2020] [Accepted: 04/15/2020] [Indexed: 12/26/2022]
Abstract
Cystic fibrosis (CF) is the most common autosomal-recessive disease in Caucasians caused by mutations in the CF transmembrane regulator (CFTR) gene. Patients are usually diagnosed in infancy and are burdened with extensive medical treatments throughout their lives. One of the first documented biochemical defects in CF, which predates the cloning of CFTR gene for almost three decades, is an imbalance in the levels of polyunsaturated fatty acids (PUFAs). The principal hallmarks of this imbalance are increased levels of arachidonic acid and decreased levels of docosahexaenoic acids (DHA) in CF. This pro-inflammatory profile of PUFAs is an important component of sterile inflammation in CF, which is known to be detrimental, rather than protective for the patients. Despite decades of intensive research, the mechanistic basis of this phenomenon remains unclear. In this review we summarized the current knowledge on the biochemistry of PUFAs, with a focus on the metabolism of AA and DHA in CF. Finally, a synthetic retinoid called fenretinide (N-(4-hydroxy-phenyl) retinamide) was shown to be able to correct the pro-inflammatory imbalance of PUFAs in CF. Therefore, its pharmacological actions and clinical potential are briefly discussed as well.
Collapse
Affiliation(s)
- Dušan Garić
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- Program in Infectious Diseases and Immunity in Global Health, McGill University Health Center, 1001 Decarie Boulevard, Room EM3-3211, Montreal, QC, H4A 3J1, Canada
| | - Daciana Catalina Dumut
- Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, QC, Canada
- Program in Infectious Diseases and Immunity in Global Health, McGill University Health Center, 1001 Decarie Boulevard, Room EM3-3211, Montreal, QC, H4A 3J1, Canada
| | - Juhi Shah
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
- Program in Infectious Diseases and Immunity in Global Health, McGill University Health Center, 1001 Decarie Boulevard, Room EM3-3211, Montreal, QC, H4A 3J1, Canada
| | - Juan Bautista De Sanctis
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Danuta Radzioch
- Department of Human Genetics, McGill University, Montreal, QC, Canada.
- Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, QC, Canada.
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic.
- Program in Infectious Diseases and Immunity in Global Health, McGill University Health Center, 1001 Decarie Boulevard, Room EM3-3211, Montreal, QC, H4A 3J1, Canada.
| |
Collapse
|
6
|
Ruhanen H, Haridas PAN, Jauhiainen M, Olkkonen VM. Angiopoietin-like protein 3, an emerging cardiometabolic therapy target with systemic and cell-autonomous functions. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158791. [PMID: 32777482 DOI: 10.1016/j.bbalip.2020.158791] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/23/2020] [Accepted: 08/03/2020] [Indexed: 12/13/2022]
Abstract
Angiopoietin like protein 3 (ANGPTL3) is best known for its function as an inhibitor of lipoprotein and endothelial lipases. Due to the capacity of genetic or pharmacologic ANGPTL3 suppression to markedly reduce circulating lipoproteins, and the documented cardioprotection upon such suppression, ANGPTL3 has become an emerging therapy target for which both antibody and antisense oligonucleotide (ASO) therapeutics are being clinically tested. While the antibody is relatively selective for circulating ANGPTL3, the ASO also depletes the intra-hepatocellular protein, and there is emerging evidence for cell-autonomous functions of ANGPTL3 in the liver. These include regulation of hepatocyte glucose and fatty acid uptake, insulin sensitivity, LDL/VLDL remnant uptake, VLDL assembly/secretion, polyunsaturated fatty acid (PUFA) and PUFA-derived lipid mediator content, and gene expression. In this review we elaborate on (i) why ANGPTL3 is considered one of the most promising new cardiometabolic therapy targets, and (ii) the present evidences for its intra-hepatocellular or cell-autonomous functions.
Collapse
Affiliation(s)
- Hanna Ruhanen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Molecular and Integrative Biosciences, University of Helsinki, Finland
| | | | - Matti Jauhiainen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Vesa M Olkkonen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Anatomy, Faculty of Medicine, University of Helsinki, Finland.
| |
Collapse
|
7
|
Ruhanen H, Haridas PAN, Minicocci I, Taskinen JH, Palmas F, di Costanzo A, D'Erasmo L, Metso J, Partanen J, Dalli J, Zhou Y, Arca M, Jauhiainen M, Käkelä R, Olkkonen VM. ANGPTL3 deficiency alters the lipid profile and metabolism of cultured hepatocytes and human lipoproteins. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158679. [PMID: 32151767 DOI: 10.1016/j.bbalip.2020.158679] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 02/28/2020] [Accepted: 03/04/2020] [Indexed: 02/08/2023]
Abstract
Loss-of-function (LOF) mutations in ANGPTL3, an inhibitor of lipoprotein lipase (LPL), cause a drastic reduction of serum lipoproteins and protect against the development of atherosclerotic cardiovascular disease. Therefore, ANGPTL3 is a promising therapy target. We characterized the impacts of ANGPTL3 depletion on the immortalized human hepatocyte (IHH) transcriptome, lipidome and human plasma lipoprotein lipidome. The transcriptome of ANGPTL3 knock-down (KD) cells showed altered expression of several pathways related to lipid metabolism. Accordingly, ANGPTL3 depleted IHH displayed changes in cellular overall fatty acid (FA) composition and in the lipid species composition of several lipid classes, characterized by abundant n-6 and n-3 polyunsaturated FAs (PUFAs). This PUFA increase coincided with an elevation of lipid mediators, among which there were species relevant for resolution of inflammation, protection from lipotoxic and hypoxia-induced ER stress, hepatic steatosis and insulin resistance or for the recovery from cardiovascular events. Cholesterol esters were markedly reduced in ANGPTL3 KD IHH, coinciding with suppression of the SOAT1 mRNA and protein. ANGPTL3 LOF caused alterations in plasma lipoprotein FA and lipid species composition. All lipoprotein fractions of the ANGPTL3 LOF subjects displayed a marked drop of 18:2n-6, while several highly unsaturated triacylglycerol (TAG) species were enriched. The present work reveals distinct impacts of ANGPTL3 depletion on the hepatocellular lipidome, transcriptome and lipid mediators, as well as on the lipidome of lipoproteins isolated from plasma of ANGPTL3-deficient human subjects. It is important to consider these lipidomics and transcriptomics findings when targeting ANGPTL3 for therapy and translating it to the human context.
Collapse
Affiliation(s)
- Hanna Ruhanen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland; Helsinki University Lipidomics Unit (HiLIPID), Helsinki Institute for Life Science (HiLIFE), Helsinki, Finland
| | | | - Ilenia Minicocci
- Department of Translational and Precision Medicine, Sapienza University of Rome, Italy
| | - Juuso H Taskinen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Francesco Palmas
- Lipid Mediator Unit, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Alessia di Costanzo
- Department of Translational and Precision Medicine, Sapienza University of Rome, Italy
| | - Laura D'Erasmo
- Department of Translational and Precision Medicine, Sapienza University of Rome, Italy
| | - Jari Metso
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | | | - Jesmond Dalli
- Lipid Mediator Unit, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom; Centre for Inflammation and Therapeutic Innovation, Queen Mary University of London, London, UK
| | - You Zhou
- Systems Immunity University Research Institute and Division of Infection & Immunity, Cardiff University, Cardiff, United Kingdom
| | - Marcello Arca
- Department of Translational and Precision Medicine, Sapienza University of Rome, Italy
| | - Matti Jauhiainen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Reijo Käkelä
- Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland; Helsinki University Lipidomics Unit (HiLIPID), Helsinki Institute for Life Science (HiLIFE), Helsinki, Finland
| | - Vesa M Olkkonen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Anatomy, University of Helsinki, Finland.
| |
Collapse
|
8
|
Werner M, Jordan PM, Romp E, Czapka A, Rao Z, Kretzer C, Koeberle A, Garscha U, Pace S, Claesson HE, Serhan CN, Werz O, Gerstmeier J. Targeting biosynthetic networks of the proinflammatory and proresolving lipid metabolome. FASEB J 2019; 33:6140-6153. [PMID: 30735438 DOI: 10.1096/fj.201802509r] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Nonsteroidal anti-inflammatory drugs interfere with the metabolism of arachidonic acid to proinflammatory prostaglandins and leukotrienes by targeting cyclooxygenases (COXs), 5-lipoxygenase (LOX), or the 5-LOX-activating protein (FLAP). These and related enzymes act in conjunction with marked crosstalk within a complex lipid mediator (LM) network where also specialized proresolving LMs (SPMs) are formed. Here, we present how prominent LM pathways can be differentially modulated in human proinflammatory M1 and proresolving M2 macrophage phenotypes that, upon exposure to Escherichia coli, produce either abundant prostaglandins and leukotrienes (M1) or SPMs (M2). Targeted liquid chromatography-tandem mass spectrometry-based metabololipidomics was applied to analyze and quantify the specific LM profiles. Besides expected on-target actions, we found that: 1) COX or 15-LOX-1 inhibitors elevate inflammatory leukotriene levels, 2) FLAP and 5-LOX inhibitors reduce leukotrienes in M1 but less so in M2 macrophages, 3) zileuton blocks resolution-initiating SPM biosynthesis, whereas FLAP inhibition increases SPM levels, and 4) that the 15-LOX-1 inhibitor 3887 suppresses SPM formation in M2 macrophages. Conclusively, interference with discrete LM biosynthetic enzymes in different macrophage phenotypes considerably affects the LM metabolomes with potential consequences for inflammation-resolution pharmacotherapy. Our data may allow better appraisal of the therapeutic potential of these drugs to intervene with inflammatory disorders.-Werner, M., Jordan, P. M., Romp, E., Czapka, A., Rao, Z., Kretzer, C., Koeberle, A., Garscha, U., Pace, S., Claesson, H.-E., Serhan, C. N., Werz, O., Gerstmeier, J. Targeting biosynthetic networks of the proinflammatory and proresolving lipid metabolome.
Collapse
Affiliation(s)
- Markus Werner
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Paul M Jordan
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Erik Romp
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Anna Czapka
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Zhigang Rao
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Christian Kretzer
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Andreas Koeberle
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Ulrike Garscha
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Simona Pace
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Hans-Erik Claesson
- Division of Hematology, Department of Medicine, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Charles N Serhan
- Department of Anesthesia, Perioperative and Pain Medicine, Center for Experimental Therapeutics and Reperfusion Injury, Brigham and Women's Hospital-Harvard Medical School, Boston, Massachusetts, USA
| | - Oliver Werz
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| | - Jana Gerstmeier
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich Schiller University Jena, Jena, Germany
| |
Collapse
|
9
|
Selectivity of phospholipid hydrolysis by phospholipase A 2 enzymes in activated cells leading to polyunsaturated fatty acid mobilization. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:772-783. [PMID: 30010011 DOI: 10.1016/j.bbalip.2018.07.002] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/08/2018] [Accepted: 07/10/2018] [Indexed: 12/14/2022]
Abstract
Phospholipase A2s are enzymes that hydrolyze the fatty acid at the sn-2 position of the glycerol backbone of membrane glycerophospholipids. Given the asymmetric distribution of fatty acids within phospholipids, where saturated fatty acids tend to be present at the sn-1 position, and polyunsaturated fatty acids such as those of the omega-3 and omega-6 series overwhelmingly localize in the sn-2 position, the phospholipase A2 reaction is of utmost importance as a regulatory checkpoint for the mobilization of these fatty acids and the subsequent synthesis of proinflammatory omega-6-derived eicosanoids on one hand, and omega-3-derived specialized pro-resolving mediators on the other. The great variety of phospholipase A2s, their differential substrate selectivity under a variety of pathophysiological conditions, as well as the different compartmentalization of each enzyme and accessibility to substrate, render this class of enzymes also key to membrane phospholipid remodeling reactions, and the generation of specific lipid mediators not related with canonical metabolites of omega-6 or omega-3 fatty acids. This review highlights novel findings regarding the selective hydrolysis of phospholipids by phospholipase A2s and the influence this may have on the ability of these enzymes to generate distinct lipid mediators with essential functions in biological processes. This brings a new understanding of the cellular roles of these enzymes depending upon activation conditions.
Collapse
|
10
|
Mouchlis VD, Chen Y, McCammon JA, Dennis EA. Membrane Allostery and Unique Hydrophobic Sites Promote Enzyme Substrate Specificity. J Am Chem Soc 2018; 140:3285-3291. [PMID: 29342349 PMCID: PMC5846079 DOI: 10.1021/jacs.7b12045] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
We
demonstrate that lipidomics coupled with molecular dynamics
reveal unique phospholipase A2 specificity toward membrane
phospholipid substrates. We discovered unexpected headgroup and acyl-chain
specificity for three major human phospholipases A2. The
differences between each enzyme’s specificity, coupled with
molecular dynamics-based structural and binding studies, revealed
unique binding sites and interfacial surface binding moieties for
each enzyme that explain the observed specificity at a hitherto inaccessible
structural level. Surprisingly, we discovered that a unique hydrophobic
binding site for the cleaved fatty acid dominates each enzyme’s
specificity rather than its catalytic residues and polar headgroup
binding site. Molecular dynamics simulations revealed the optimal
phospholipid binding mode leading to a detailed understanding of the
preference of cytosolic phospholipase A2 for cleavage of
proinflammatory arachidonic acid, calcium-independent phospholipase
A2, which is involved in membrane remodeling for cleavage
of linoleic acid and for antibacterial secreted phospholipase A2 favoring linoleic acid, saturated fatty acids, and phosphatidylglycerol.
Collapse
Affiliation(s)
- Varnavas D Mouchlis
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine , University of California , San Diego, La Jolla , California 92093-0601 , United States
| | - Yuan Chen
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine , University of California , San Diego, La Jolla , California 92093-0601 , United States
| | - J Andrew McCammon
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine , University of California , San Diego, La Jolla , California 92093-0601 , United States
| | - Edward A Dennis
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine , University of California , San Diego, La Jolla , California 92093-0601 , United States
| |
Collapse
|
11
|
McBurney MI, Bird JK. Impact of Biological Feedback and Incentives on Blood Fatty Acid Concentrations, Including Omega-3 Index, in an Employer-Based Wellness Program. Nutrients 2017; 9:E842. [PMID: 28783061 PMCID: PMC5579635 DOI: 10.3390/nu9080842] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 07/24/2017] [Accepted: 07/31/2017] [Indexed: 01/15/2023] Open
Abstract
Eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3) are important fatty acids for the retina and brain. More than 95% of Americans have suboptimal EPA + DHA blood concentrations. This cross-sectional employer-based study assessed whole blood fatty acid levels of volunteers participating in an onsite wellness biometric screening program and was designed to determine if an incentive, a $5 coupon for a 90-day supply of fish oil supplement typically costing $18-30, stimulated incremental dietary behavior change relative to nutritional status assessment alone to increase EPA + DHA concentrations. Volunteers completed a dietary survey and finger stick blood samples were collected to be analyzed for fatty acid composition. In addition, 636 individuals participated in the initial onsite biometric screening. Three months later, and without prior knowledge, all employees were invited to a second screening. At the second screening, 198 employees volunteered for the first time and 149 employees had a second test (17.9%). At baseline, the average age (n = 834) was 45 year and omega-3 index was 5.0% with 41% female. EPA + DHA concentration, i.e., omega-3 index, was significantly lower in men (4.8%) than women (5.2%), as were DHA and linoleic acid (LA) concentrations (p < 0.05). Baseline omega-3 index was positively and linearly associated with omega-3 intake. Only 4% of volunteers had an omega-3 index >8% on initial screening. Among the 149 individuals with two measurements, omega-3 intake from supplements, but not food, increased significantly from 258 to 445 mg/d (p < 0.01) at the second test as did the omega-3 index (+0.21, p < 0.02). In this employed population, only 1% redeemed a coupon for an omega-3 supplement.
Collapse
Affiliation(s)
| | - Julia K Bird
- DSM Nutritional Products, Alexander Fleminglaan 1, 2613AX Delft, The Netherlands.
| |
Collapse
|
12
|
Palavicini JP, Wang C, Chen L, Hosang K, Wang J, Tomiyama T, Mori H, Han X. Oligomeric amyloid-beta induces MAPK-mediated activation of brain cytosolic and calcium-independent phospholipase A 2 in a spatial-specific manner. Acta Neuropathol Commun 2017; 5:56. [PMID: 28750656 PMCID: PMC5530945 DOI: 10.1186/s40478-017-0460-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 07/19/2017] [Indexed: 01/01/2023] Open
Abstract
Alzheimer's disease (AD) is histopathologically characterized by the build-up of fibrillar amyloid beta (Aβ) in the form of amyloid plaques and the development of intraneuronal neurofibrillary tangles consisting of aggregated hyperphosphorylated Tau. Although amyloid fibrils were originally considered responsible for AD pathogenesis, recent convincing evidence strongly implicates soluble oligomeric Aβ as the primary neurotoxic species driving disease progression. A third largely ignored pathological hallmark, originally described by Alois Alzheimer, is the presence of "adipose inclusions", suggestive of aberrant lipid metabolism. The molecular mechanisms underlying these "lipoid granules", as well as their potential link to soluble and/or fibrillar Aβ remain largely unknown. Seeking to better-understand these conundrums, we took advantage of the powerful technology of multidimensional mass spectrometry-based shotgun lipidomics and an AD transgenic mouse model overexpressing mutant amyloid precursor protein (APP E693Δ-Osaka-), where AD-like pathology and neurodegeneration occur as a consequence of oligomeric Aβ accumulation in the absence of amyloid plaques. Our results revealed for the first time that APP overexpression and oligomeric Aβ accumulation lead to an additive global accumulation of nonesterified polyunsaturated fatty acids (PUFAs) independently of amyloid plaques. Furthermore, we revealed that this accumulation is mediated by an increase in phospholipase A2 (PLA2) activity, evidenced by an accumulation of sn-1 lysophosphatidylcholine and by MAPK-mediated phosphorylation/activation of group IV Ca2+-dependent cytosolic (cPLA2) and the group VI Ca2+-independent PLA2 (iPLA2) independently of PKC. We further revealed that Aβ-induced oxidative stress also disrupts lipid metabolism via reactive oxygen species-mediated phospholipid cleavage leading to increased sn-2 lysophosphatidylcholine as well as lipid peroxidation and the subsequent accumulation of 4-hydroxynonenal. Brain histological studies implicated cPLA2 activity with arachidonic acid accumulation within myelin-rich regions, and iPLA2 activity with docosahexaenoic acid accumulation within pyramidal neuron-rich regions. Taken together, our results suggest that PLA2-mediated accumulation of free PUFAs drives AD-related disruption of brain lipid metabolism.
Collapse
|
13
|
Tigistu-Sahle F, Lampinen M, Kilpinen L, Holopainen M, Lehenkari P, Laitinen S, Käkelä R. Metabolism and phospholipid assembly of polyunsaturated fatty acids in human bone marrow mesenchymal stromal cells. J Lipid Res 2016; 58:92-110. [PMID: 27856675 DOI: 10.1194/jlr.m070680] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 11/08/2016] [Indexed: 01/06/2023] Open
Abstract
High arachidonic acid (20:4n-6) and low n-3 PUFA levels impair the capacity of cultured human bone marrow mesenchymal stromal cells (hBMSCs) to modulate immune functions. The capacity of the hBMSCs to modify PUFA structures was found to be limited. Therefore, different PUFA supplements given to the cells resulted in very different glycerophospholipid (GPL) species profiles and substrate availability for phospholipases, which have preferences for polar head group and acyl chains when liberating PUFA precursors for production of lipid mediators. When supplemented with 20:4n-6, the cells increased prostaglandin E2 secretion. However, they elongated 20:4n-6 to the less active precursor, 22:4n-6, and also incorporated it into triacylglycerols, which may have limited the proinflammatory signaling. The n-3 PUFA precursor, 18:3n-3, had little potency to reduce the GPL 20:4n-6 content, while the eicosapentaenoic (20:5n-3) and docosahexaenoic (22:6n-3) acid supplements efficiently displaced the 20:4n-6 acyls, and created diverse GPL species substrate pools allowing attenuation of inflammatory signaling. The results emphasize the importance of choosing appropriate PUFA supplements for in vitro hBMSC expansion and suggests that for optimal function they require an exogenous fatty acid source providing 20:5n-3 and 22:6n-3 sufficiently, but 20:4n-6 moderately, which calls for specifically designed optimal PUFA supplements for the cultures.
Collapse
Affiliation(s)
| | - Milla Lampinen
- Department of Biosciences University of Helsinki, Helsinki, Finland
| | - Lotta Kilpinen
- Department of Biosciences University of Helsinki, Helsinki, Finland.,Advanced Therapies and Product Development, Finnish Red Cross Blood Service, Helsinki, Finland
| | - Minna Holopainen
- Advanced Therapies and Product Development, Finnish Red Cross Blood Service, Helsinki, Finland
| | - Petri Lehenkari
- Institute of Biomedicine, Division of Surgery, University of Oulu and Clinical Research Centre, Department of Surgery and Intensive Care, Oulu, Finland.,Department of Anatomy and Cell Biology, University of Oulu, Finland and Institute of Clinical Medicine, Division of Surgery, University of Oulu and Clinical Research Centre, Department of Surgery and Intensive Care, Oulu, Finland
| | - Saara Laitinen
- Advanced Therapies and Product Development, Finnish Red Cross Blood Service, Helsinki, Finland
| | - Reijo Käkelä
- Department of Biosciences University of Helsinki, Helsinki, Finland
| |
Collapse
|
14
|
Batchu KC, Hänninen S, Jha SK, Jeltsch M, Somerharju P. Factors regulating the substrate specificity of cytosolic phospholipase A 2 -alpha in vitro. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1597-1604. [DOI: 10.1016/j.bbalip.2016.06.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 06/28/2016] [Accepted: 06/30/2016] [Indexed: 10/21/2022]
|
15
|
Bibus D, Lands B. Balancing proportions of competing omega-3 and omega-6 highly unsaturated fatty acids (HUFA) in tissue lipids. Prostaglandins Leukot Essent Fatty Acids 2015; 99:19-23. [PMID: 26002802 DOI: 10.1016/j.plefa.2015.04.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 12/18/2014] [Accepted: 04/08/2015] [Indexed: 12/30/2022]
Abstract
People eating different balances of omega-3 and omega-6 nutrients develop predictably different proportions of competing highly unsaturated fatty acids (HUFA) in their tissue lipids. While epidemiological studies have associated wide differences in HUFA balance with disease severity, some clinical studies that did not examine wide differences failed to confirm the association. We examined the degree to which the relative amount of arachidonic acid, the major precursor of omega-6 eicosanoids, differs among people who have widely different dietary intakes of omega-3 and omega-6 nutrients. Gas chromatographic analyses of human blood samples describe the balance among n-3 and n-6 HUFA for different individuals. The proportion of the omega-6 arachidonic acid, from which potent eicosanoids are formed, is not constant. It ranges from 30% to 70% of HUFA while the competing n-3 HUFA range from 60% to 10% of HUFA. Significant differences in clinical outcomes between control and intervention groups have been seen when using dietary interventions that shift the balance of n-3 and n-6 nutrients far enough to create a biologically significant difference in the HUFA balance.
Collapse
Affiliation(s)
- Doug Bibus
- Community Faculty, University of Minnesota Center for Spirituality and Healing, and Lipid Technologies LLC, P.O. Box 216, Austin, MN 55912, United States
| | - Bill Lands
- Fellow, ASN, AAAS, SFRBM, 6100 Westchester Park Drive, College Park, MD 20740, United States.
| |
Collapse
|
16
|
Lysophospholipid acyltransferases and eicosanoid biosynthesis in zebrafish myeloid cells. Prostaglandins Other Lipid Mediat 2014; 113-115:52-61. [PMID: 25175316 DOI: 10.1016/j.prostaglandins.2014.08.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 08/05/2014] [Accepted: 08/19/2014] [Indexed: 12/21/2022]
Abstract
Eicosanoids derived from the enzymatic oxidation of arachidonic acid play important roles in a large number of physiological and pathological processes in humans. Many animal and cellular models have been used to investigate the intricate mechanisms regulating their biosynthesis and actions. Zebrafish is a widely used model to study the embryonic development of vertebrates. It expresses homologs of the key enzymes involved in eicosanoid production, and eicosanoids have been detected in extracts from adult or embryonic fish. In this study we prepared cell suspensions from kidney marrow, the main hematopoietic organ in fish. Upon stimulation with calcium ionophore, these cells produced eicosanoids including PGE2, LTB4, 5-HETE and, most abundantly, 12-HETE. They also produced small amounts of LTB5 derived from eicosapentaenoic acid. These eicosanoids were also produced in kidney marrow cells stimulated with ATP, and this production was greatly enhanced by preincubation with thimerosal, an inhibitor of arachidonate reacylation into phospholipids. Microsomes from these cells exhibited acyltransferase activities consistent with expression of MBOAT5/LPCAT3 and MBOAT7/LPIAT1, the main arachidonoyl-CoA:lysophospholipid acyltransferases. In summary, this work introduces a new cellular model to study the regulation of eicosanoid production through a phospholipid deacylation-reacylation cycle from a well-established, versatile vertebrate model species.
Collapse
|
17
|
Yokokura Y, Isobe Y, Matsueda S, Iwamoto R, Goto T, Yoshioka T, Urabe D, Inoue M, Arai H, Arita M. Identification of 14,20-dihydroxy-docosahexaenoic acid as a novel anti-inflammatory metabolite. ACTA ACUST UNITED AC 2014; 156:315-21. [DOI: 10.1093/jb/mvu044] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
18
|
Astarita G, McKenzie JH, Wang B, Strassburg K, Doneanu A, Johnson J, Baker A, Hankemeier T, Murphy J, Vreeken RJ, Langridge J, Kang JX. A protective lipidomic biosignature associated with a balanced omega-6/omega-3 ratio in fat-1 transgenic mice. PLoS One 2014; 9:e96221. [PMID: 24760204 PMCID: PMC3997567 DOI: 10.1371/journal.pone.0096221] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 04/04/2014] [Indexed: 01/26/2023] Open
Abstract
A balanced omega-6/omega-3 polyunsaturated fatty acid (PUFA) ratio has been linked to health benefits and the prevention of many chronic diseases. Current dietary intervention studies with different sources of omega-3 fatty acids (omega-3) lack appropriate control diets and carry many other confounding factors derived from genetic and environmental variability. In our study, we used the fat-1 transgenic mouse model as a proxy for long-term omega-3 supplementation to determine, in a well-controlled manner, the molecular phenotype associated with a balanced omega-6/omega-3 ratio. The fat-1 mouse can convert omega-6 to omega-3 PUFAs, which protect against a wide variety of diseases including chronic inflammatory diseases and cancer. Both wild-type (WT) and fat-1 mice were subjected to an identical diet containing 10% corn oil, which has a high omega-6 content similar to that of the Western diet, for a six-month duration. We used a multi-platform lipidomic approach to compare the plasma lipidome between fat-1 and WT mice. In fat-1 mice, an unbiased profiling showed a significant increase in the levels of unesterified eicosapentaenoic acid (EPA), EPA-containing cholesteryl ester, and omega-3 lysophosphospholipids. The increase in omega-3 lipids is accompanied by a significant reduction in omega-6 unesterified docosapentaenoic acid (omega-6 DPA) and DPA-containing cholesteryl ester as well as omega-6 phospholipids and triacylglycerides. Targeted lipidomics profiling highlighted a remarkable increase in EPA-derived diols and epoxides formed via the cytochrome P450 (CYP450) pathway in the plasma of fat-1 mice compared with WT mice. Integration of the results of untargeted and targeted analyses has identified a lipidomic biosignature that may underlie the healthful phenotype associated with a balanced omega-6/omega-3 ratio, and can potentially be used as a circulating biomarker for monitoring the health status and the efficacy of omega-3 intervention in humans.
Collapse
Affiliation(s)
- Giuseppe Astarita
- Health Sciences, Waters Corporation, Milford, Massachusetts, United States of America
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC, United States of America
- * E-mail: (GA); (JXK)
| | - Jennifer H. McKenzie
- Laboratory for Lipid Medicine and Technology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Bin Wang
- Laboratory for Lipid Medicine and Technology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Katrin Strassburg
- Analytical Biosciences, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
- Netherlands Metabolomics Centre, Leiden University, Leiden, The Netherlands
| | - Angela Doneanu
- Health Sciences, Waters Corporation, Milford, Massachusetts, United States of America
| | - Jay Johnson
- Health Sciences, Waters Corporation, Milford, Massachusetts, United States of America
| | - Andrew Baker
- Health Sciences, Waters Corporation, Milford, Massachusetts, United States of America
| | - Thomas Hankemeier
- Analytical Biosciences, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
- Netherlands Metabolomics Centre, Leiden University, Leiden, The Netherlands
| | - James Murphy
- Health Sciences, Waters Corporation, Milford, Massachusetts, United States of America
| | - Rob J. Vreeken
- Analytical Biosciences, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
- Netherlands Metabolomics Centre, Leiden University, Leiden, The Netherlands
| | - James Langridge
- Health Sciences, Waters Corporation, Milford, Massachusetts, United States of America
| | - Jing X. Kang
- Laboratory for Lipid Medicine and Technology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (GA); (JXK)
| |
Collapse
|
19
|
Fracture healing and lipid mediators. BONEKEY REPORTS 2014; 3:517. [PMID: 24795811 DOI: 10.1038/bonekey.2014.12] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 01/03/2014] [Indexed: 01/11/2023]
Abstract
Lipid mediators regulate bone regeneration during fracture healing. Prostaglandins and leukotrienes are well-known lipid mediators that regulate inflammation and are synthesized from the Ω-6 fatty acid, arachidonic acid. Cyclooxygenase (COX-1 or COX-2) and 5-lipoxygenase (5-LO) catalyze the initial enzymatic steps in the synthesis of prostaglandins and leukotrienes, respectively. Inhibition or genetic ablation of COX-2 activity impairs fracture healing in animal models. Genetic ablation of COX-1 does not affect the fracture callus strength in mice, suggesting that COX-2 activity is primarily responsible for regulating fracture healing. Inhibition of cyclooxygenase activity with nonsteroidal anti-inflammatory drugs (NSAIDs) is performed clinically to reduce heterotopic ossification, although clinical evidence that NSAID treatment impairs fracture healing remains controversial. In contrast, inhibition or genetic ablation of 5-LO activity accelerates fracture healing in animal models. Even though prostaglandins and leukotrienes regulate inflammation, loss of COX-2 or 5-LO activity appears to primarily affect chondrogenesis during fracture healing. Prostaglandin or prostaglandin analog treatment, prostaglandin-specific synthase inhibition and prostaglandin or leukotriene receptor antagonism also affect callus chondrogenesis. Unlike the Ω-6-derived lipid mediators, lipid mediators derived from Ω-3 fatty acids, such as resolvin E1 (RvE1), have anti-inflammatory activity. In vivo, RvE1 can inhibit osteoclastogenesis and limit bone resorption. Although Ω-6 and Ω-3 lipid mediators have clear-cut effects on inflammation, the role of these lipid mediators in bone regeneration is more complex, with apparent effects on callus chondrogenesis and bone remodeling.
Collapse
|
20
|
Leigh NJ, Nelson JW, Mellas RE, Aguirre A, Baker OJ. Expression of resolvin D1 biosynthetic pathways in salivary epithelium. J Dent Res 2014; 93:300-5. [PMID: 24389810 DOI: 10.1177/0022034513519108] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Resolvins are potent anti-inflammatory mediators derived from ω-3 fatty acids. Results from our previous studies indicated that resolvin D1 (RvD1) blocks pro-inflammatory responses in salivary glands. Furthermore, RvD1 enhances salivary epithelial integrity, demonstrating its potential use for the restoration of salivary gland function in Sjögren's syndrome (SS). We investigated whether the RvD1 biosynthetic machinery (e.g., cytosolic phospholipase A2, calcium-independent phospholipase A2, 12/15 and 5-lipoxygenase) is expressed in mouse submandibular glands (mSMG), using qPCR and Western blot analyses. Additionally, we determined the localization of RvD1 biosynthetic machinery in mSMG and human minor salivary glands (hMSG), with and without SS, using confocal microscopy. Finally, we measured RvD1 levels in cell supernatants from mSMG cell cultures and freshly isolated mSMG cells, with and without SS, using ELISA. Our results indicate that: (1) RvD1 machinery is expressed in mouse and human salivary glands; (2) polar distribution of RvD1 biosynthetic machinery is lost in hMSG with SS; (3) RvD1 levels in mSMG cell culture supernatants increased with time; and (4) RvD1 levels in mSMG cell supernatants, with and without SS, were similar. These studies demonstrate that the RvD1 biosynthesis machinery is expressed and functional in salivary glands with and without SS.
Collapse
MESH Headings
- Animals
- Arachidonate 12-Lipoxygenase/analysis
- Arachidonate 12-Lipoxygenase/metabolism
- Arachidonate 15-Lipoxygenase/analysis
- Arachidonate 15-Lipoxygenase/metabolism
- Arachidonate 5-Lipoxygenase/analysis
- Arachidonate 5-Lipoxygenase/metabolism
- Cell Culture Techniques
- Cell Membrane/enzymology
- Cells, Cultured
- Cytosol/enzymology
- Docosahexaenoic Acids/analysis
- Docosahexaenoic Acids/biosynthesis
- Epithelium/metabolism
- Female
- Humans
- Mice
- Mice, Inbred C57BL
- Mice, Inbred NOD
- Mice, Inbred Strains
- Phospholipases A2, Calcium-Independent/analysis
- Phospholipases A2, Calcium-Independent/metabolism
- Phospholipases A2, Cytosolic/analysis
- Phospholipases A2, Cytosolic/metabolism
- Salivary Glands, Minor/metabolism
- Salivary Glands, Minor/pathology
- Sjogren's Syndrome/metabolism
- Sjogren's Syndrome/pathology
- Submandibular Gland/cytology
- Submandibular Gland/metabolism
Collapse
Affiliation(s)
- N J Leigh
- Department of Oral Biology, University at Buffalo, The State University of New York, Buffalo, NY 14214-3092, USA
| | | | | | | | | |
Collapse
|
21
|
Kitson AP, Marks KA, Shaw B, Mutch DM, Stark KD. Treatment of ovariectomized rats with 17β-estradiol increases hepatic delta-6 desaturase enzyme expression and docosahexaenoic acid levels in hepatic and plasma phospholipids. Prostaglandins Leukot Essent Fatty Acids 2013; 89:81-8. [PMID: 23764042 DOI: 10.1016/j.plefa.2013.05.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 05/10/2013] [Accepted: 05/17/2013] [Indexed: 01/25/2023]
Abstract
Higher docosahexaenoic acid (DHA) in females compared with males suggests ovarian hormones increase DHA production. Eight-week old rats were ovariectomized or sham operated (SHAM), and ovariectomized rats were treated with implanted pellets providing 17β-estradiol (OVX+E), progesterone (OVX+P), both (OVX+PE) or neither (OVX) for 14 days. Immunoblot and fatty acid analysis were performed on all samples, and microarray analysis was performed on OVX and SHAM groups. Increased Δ6-desaturase in OVX relative to SHAM was observed by microarray (12% higher) and immunoblot (31% higher). OVX+E and OVX+PE rats had 39% and 42% higher Δ6-desaturase content, respectively, compared with OVX. OVX+E and OVX+PE also increased phospholipid DHA concentrations in liver (increase of 34% and 40%, respectively) and plasma (increase of 70% and 74%, respectively) relative to OVX. Progesterone exerted no effect on Δ6-desaturase or DHA. These results indicate that 17β-estradiol increases DHA through increased Δ6-desaturase, possibly explaining sex differences in DHA.
Collapse
Affiliation(s)
- Alex P Kitson
- Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada N2L 3G1
| | | | | | | | | |
Collapse
|
22
|
Keinan D, Leigh NJ, Nelson JW, De Oleo L, Baker OJ. Understanding resolvin signaling pathways to improve oral health. Int J Mol Sci 2013; 14:5501-18. [PMID: 23528855 PMCID: PMC3634469 DOI: 10.3390/ijms14035501] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 02/19/2013] [Accepted: 02/22/2013] [Indexed: 12/15/2022] Open
Abstract
The discovery of resolvins has been a major breakthrough for understanding the processes involved in resolution of inflammation. Resolvins belong to a family of novel lipid mediators that possess dual anti-inflammatory and pro-resolution actions. Specifically, they protect healthy tissue during immune-inflammatory responses to infection or injury, thereby aiding inflammation resolution and promoting tissue healing. One of the major concerns in modern medicine is the management and treatment of oral diseases, as they are related to systemic outcomes impacting the quality of life of many patients. This review summarizes known signaling pathways utilized by resolvins to regulate inflammatory responses associated with the oral cavity.
Collapse
Affiliation(s)
- David Keinan
- Department of Periodontics and Endodontics, School of Dental Medicine, University at Buffalo, the State University of New York, Buffalo, NY 14214-3932, USA; E-Mail:
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, the State University of New York, Buffalo, NY 14214-3932, USA; E-Mails: (N.J.L.); (J.W.N.); (L.D.O.)
| | - Noel J. Leigh
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, the State University of New York, Buffalo, NY 14214-3932, USA; E-Mails: (N.J.L.); (J.W.N.); (L.D.O.)
| | - Joel W. Nelson
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, the State University of New York, Buffalo, NY 14214-3932, USA; E-Mails: (N.J.L.); (J.W.N.); (L.D.O.)
| | - Laura De Oleo
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, the State University of New York, Buffalo, NY 14214-3932, USA; E-Mails: (N.J.L.); (J.W.N.); (L.D.O.)
| | - Olga J. Baker
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, the State University of New York, Buffalo, NY 14214-3932, USA; E-Mails: (N.J.L.); (J.W.N.); (L.D.O.)
- To whom correspondence should be addressed; E-Mail: ; Tel.: +1-716-829-3667; Fax: +1-716-829-3942
| |
Collapse
|
23
|
Abstract
Long chain omega-3 polyunsaturated fatty acids (LC n-3 PUFAs) are recommended for management of patients with wide-ranging chronic diseases, including coronary heart disease, rheumatoid arthritis, dementia, and depression. Increased consumption of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is recommended by many health authorities to prevent (up to 0.5 g/day) or treat chronic disease (1.0 g/day for coronary heart disease; 1.2–4 g/day for elevated triglyceride levels). Recommendations for dietary intake of LC n-3 PUFAs are often provided for α-linolenic acid, and for the combination of EPA and DHA. However, many studies have also reported differential effects of EPA, DHA and their metabolites in the clinic and at the laboratory bench. The aim of this article is to review studies that have identified divergent responses to EPA and DHA, and to explore reasons for these differences. In particular, we review potential contributing factors such as differential membrane incorporation, modulation of gene expression, activation of signaling pathways and metabolite formation. We suggest that there may be future opportunity to refine recommendations for intake of individual LC n-3 PUFAs.
Collapse
Affiliation(s)
- Fraser D Russell
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore, Queensland 4556, Australia.
| | | |
Collapse
|
24
|
Consequences of essential fatty acids. Nutrients 2012; 4:1338-57. [PMID: 23112921 PMCID: PMC3475243 DOI: 10.3390/nu4091338] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 08/18/2012] [Accepted: 09/13/2012] [Indexed: 12/17/2022] Open
Abstract
Essential fatty acids (EFA) are nutrients that form an amazingly large array of bioactive mediators that act on a large family of selective receptors. Nearly every cell and tissue in the human body expresses at least one of these receptors, allowing EFA-based signaling to influence nearly every aspect of human physiology. In this way, the health consequences of specific gene-environment interactions with these nutrients are more extensive than often recognized. The metabolic transformations have similar competitive dynamics for the n-3 and n-6 homologs when converting dietary EFA from the external environment of foods into the highly unsaturated fatty acid (HUFA) esters that accumulate in the internal environment of cells and tissues. In contrast, the formation and action of bioactive mediators during tissue responses to stimuli tend to selectively create more intense consequences for n-6 than n-3 homologs. Both n-3 and n-6 nutrients have beneficial actions, but many common health disorders are undesired consequences of excessive actions of tissue n-6 HUFA which are preventable. This review considers the possibility of preventing imbalances in dietary n-3 and n-6 nutrients with informed voluntary food choices. That action may prevent the unintended consequences that come from eating imbalanced diets which support excessive chronic actions of n-6 mediators that harm human health. The consequences from preventing n-3 and n-6 nutrient imbalances on a nationwide scale may be very large, and they need careful evaluation and implementation to avoid further harmful consequences for the national economy.
Collapse
|
25
|
Omega-3 fatty acids cause dramatic changes in TLR4 and purinergic eicosanoid signaling. Proc Natl Acad Sci U S A 2012; 109:8517-22. [PMID: 22586114 DOI: 10.1073/pnas.1200189109] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Dietary fish oil containing ω3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), elicit cardioprotective and anti-inflammatory effects through unresolved mechanisms that may involve competition and inhibition at multiple levels. Here, we report the effects of arachidonic acid (AA), EPA, and DHA supplementation on membrane incorporation, phospholipase A(2) catalyzed release, and eicosanoid production in RAW264.7 macrophages. Using a targeted lipidomics approach, we observed that Toll-like receptor 4 and purinergic receptor activation of supplemented cells leads to the release of 22-carbon fatty acids that potently inhibit cyclooxygenase pathways. This inhibition was able to shunt metabolism of AA to lipoxygenase pathways, augmenting leukotriene and other lipoxygenase mediator synthesis. In resident peritoneal macrophages, docosapentaenoic acid (DPA) was responsible for cyclooxygenase inhibition after EPA supplementation, offering fresh insights into how EPA exerts anti-inflammatory effects indirectly through elongation to 22-carbon DPA.
Collapse
|
26
|
Ozsoy O, Seval-Celik Y, Hacioglu G, Yargicoglu P, Demir R, Agar A, Aslan M. The influence and the mechanism of docosahexaenoic acid on a mouse model of Parkinson’s disease. Neurochem Int 2011; 59:664-70. [DOI: 10.1016/j.neuint.2011.06.012] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 05/23/2011] [Accepted: 06/18/2011] [Indexed: 01/19/2023]
|
27
|
Westphal C, Konkel A, Schunck WH. CYP-eicosanoids--a new link between omega-3 fatty acids and cardiac disease? Prostaglandins Other Lipid Mediat 2011; 96:99-108. [PMID: 21945326 DOI: 10.1016/j.prostaglandins.2011.09.001] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 08/31/2011] [Accepted: 09/06/2011] [Indexed: 12/31/2022]
Abstract
Fish oil omega-3 fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) protect against arrhythmia and sudden cardiac death by largely unknown mechanisms. Recent in vitro and in vivo studies demonstrate that arachidonic acid (AA) metabolizing cytochrome P450-(CYP) enzymes accept EPA and DHA as efficient alternative substrates. Dietary EPA/DHA supplementation causes a profound shift of the cardiac CYP-eicosanoid profile from AA- to EPA- and DHA-derived epoxy- and hydroxy-metabolites. CYP2J2 and other CYP epoxygenases preferentially epoxidize the ω-3 double bond of EPA and DHA. The corresponding metabolites, 17,18-epoxy-EPA and 19,20-epoxy-DHA, dominate the CYP-eicosanoid profile of the rat heart after EPA/DHA supplementation. The (ω-3)-epoxyeicosanoids show highly potent antiarrhythmic properties in neonatal cardiomyocytes, suggesting that these metabolites may specifically contribute to the cardioprotective effects of omega-3 fatty acids. This hypothesis is discussed in the context of recent findings that revealed CYP-eicosanoid mediated mechanisms in cardiac ischemia-reperfusion injury and maladaptive cardiac hypertrophy.
Collapse
Affiliation(s)
- Christina Westphal
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | | | | |
Collapse
|
28
|
Sun H, Hu Y, Gu Z, Wilson MD, Chen YQ, Rudel LL, Willingham MC, Edwards IJ. Endogenous synthesis of n-3 polyunsaturated fatty acids in Fat-1 mice is associated with increased mammary gland and liver syndecan-1. PLoS One 2011; 6:e20502. [PMID: 21655218 PMCID: PMC3105073 DOI: 10.1371/journal.pone.0020502] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 05/02/2011] [Indexed: 01/12/2023] Open
Abstract
Long chain n-3 PUFA have been shown to have chemopreventive properties against breast cancer through various mechanisms. One pathway, studied in human breast cancer cell lines, involves upregulation of the proteoglycan, syndecan-1 (SDC-1) by n-3 PUFA-enriched LDL. Using Fat-1 mice that are able to convert n-6 to n-3 PUFA, we tested whether SDC-1 level in vivo is elevated in mammary glands due to endogenously synthesized rather than LDL-derived n-3 PUFA. Female Fat-1 and wild type (wt) mice were fed an n-6 PUFA- enriched diet for 7 weeks. Fatty acid analysis of plasma lipoproteins showed that total n-6 PUFA reflected dietary intake similarly in both genotypes (VLDL, 36.2±2.2 and 40.9±3.9; LDL, 49.0±3.3 and 48.1±2.0; HDL, 54.6±1.2 and 58.2±1.3, mean ± SEM percent of total fatty acids for Fat-1 and wt animals respectively). Lipoprotein percent n-3 PUFA was also similar between groups. However, phospholipids and triglycerides extracted from mammary and liver tissues demonstrated significantly higher n-3 PUFA and a corresponding decrease in the ratio n-6/n-3 PUFA in Fat-1 compared to wt mice. This was accompanied by higher SDC-1 in mammary glands and livers of Fat-1 mice, thus demonstrating that endogenously synthesized n-3 PUFA may upregulate SDC-1 in the presence of high dietary n-6 PUFA.
Collapse
Affiliation(s)
- Haiguo Sun
- Department of Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Yunping Hu
- Department of Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Zhennan Gu
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Martha D. Wilson
- Department of Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Yong Q. Chen
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Lawrence L. Rudel
- Department of Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Mark C. Willingham
- Department of Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Iris J. Edwards
- Department of Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
- * E-mail: E-mail:
| |
Collapse
|
29
|
Kim HW, Rao JS, Rapoport SI, Igarashi M. Dietary n-6 PUFA deprivation downregulates arachidonate but upregulates docosahexaenoate metabolizing enzymes in rat brain. Biochim Biophys Acta Mol Cell Biol Lipids 2010; 1811:111-7. [PMID: 21070866 DOI: 10.1016/j.bbalip.2010.10.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 10/26/2010] [Accepted: 10/27/2010] [Indexed: 11/28/2022]
Abstract
BACKGROUND Dietary n-3 polyunsaturated fatty acid (PUFA) deprivation increases expression of arachidonic acid (AA 20:4n-6)-selective cytosolic phospholipase A(2) (cPLA(2)) IVA and cyclooxygenase (COX)-2 in rat brain, while decreasing expression of docosahexaenoic acid (DHA 22:6n-3)-selective calcium-independent iPLA(2) VIA. Assuming that these enzyme changes represent brain homeostatic responses to deprivation, we hypothesized that dietary n-6 PUFA deprivation would produce changes in the opposite directions. METHODS Brain expression of PUFA-metabolizing enzymes and their transcription factors was quantified in male rats fed an n-6 PUFA adequate or deficient diet for 15weeks post-weaning. RESULTS The deficient compared with adequate diet increased brain mRNA, protein and activity of iPLA(2) VIA and 15-lipoxygenase (LOX), but decreased cPLA(2) IVA and COX-2 expression. The brain protein level of the iPLA(2) transcription factor SREBP-1 was elevated, while protein levels were decreased for AP-2α and NF-κB p65, cPLA(2) and COX-2 transcription factors, respectively. CONCLUSIONS With dietary n-6 PUFA deprivation, rat brain PUFA metabolizing enzymes and some of their transcription factors change in a way that would homeostatically dampen reductions in brain n-6 PUFA concentrations and metabolism, while n-3 PUFA metabolizing enzyme expression is increased. The changes correspond to reported in vitro enzyme selectivities for AA compared with DHA.
Collapse
Affiliation(s)
- Hyung-Wook Kim
- National Institute on Aging, National Institutes of Health, Bethesda, MD, USA.
| | | | | | | |
Collapse
|
30
|
Ramadan E, Rosa AO, Chang L, Chen M, Rapoport SI, Basselin M. Extracellular-derived calcium does not initiate in vivo neurotransmission involving docosahexaenoic acid. J Lipid Res 2010; 51:2334-40. [PMID: 20388940 PMCID: PMC2903827 DOI: 10.1194/jlr.m006262] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 04/13/2010] [Indexed: 11/20/2022] Open
Abstract
In vitro studies show that docosahexaenoic acid (DHA) can be released from membrane phospholipid by Ca(2+)-independent phospholipase A(2) (iPLA(2)), Ca(2+)-independent plasmalogen PLA(2) or secretory PLA(2 (sPLA2)), but not by Ca(2+)-dependent cytosolic PLA(2) (cPLA2), which selectively releases arachidonic acid (AA). Since glutamatergic NMDA (N-methyl-D-aspartate) receptor activation allows extracellular Ca(2+) into cells, we hypothesized that brain DHA signaling would not be altered in rats given NMDA, to the extent that in vivo signaling was mediated by Ca(2+)-independent mechanisms. Isotonic saline, a subconvulsive dose of NMDA (25 mg/kg), MK-801, or MK-801 followed by NMDA was administered i.p. to unanesthetized rats. Radiolabeled DHA or AA was infused intravenously and their brain incorporation coefficients k*, measures of signaling, were imaged with quantitative autoradiography. NMDA or MK-801 compared with saline did not alter k* for DHA in any of 81 brain regions examined, whereas NMDA produced widespread and significant increments in k* for AA. In conclusion, in vivo brain DHA but not AA signaling via NMDA receptors is independent of extracellular Ca(2+) and of cPLA(2). DHA signaling may be mediated by iPLA(2), plasmalogen PLA(2), or other enzymes insensitive to low concentrations of Ca(2+). Greater AA than DHA release during glutamate-induced excitotoxicity could cause brain cell damage.
Collapse
Affiliation(s)
- Epolia Ramadan
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA.
| | | | | | | | | | | |
Collapse
|
31
|
Park Y, Harris WS. Dose-Dependent Effects ofn-3 Polyunsaturated Fatty Acids on Platelet Activation in Mildly Hypertriglyceridemic Subjects. J Med Food 2009; 12:809-13. [DOI: 10.1089/jmf.2008.1097] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yongsoon Park
- Department of Food and Nutrition, College of Human Ecology, Hanyang University, Seoul, Republic of Korea
| | - William S. Harris
- Nutrition and Metabolic Disease Research Institute, Sanford Research, South Dakota, USA
- Sanford School of Medicine, University of South Dakota, Sioux Falls, South Dakota, USA
| |
Collapse
|
32
|
Rosa AO, Rapoport SI. Intracellular- and extracellular-derived Ca(2+) influence phospholipase A(2)-mediated fatty acid release from brain phospholipids. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:697-705. [PMID: 19327408 DOI: 10.1016/j.bbalip.2009.03.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2008] [Revised: 03/01/2009] [Accepted: 03/11/2009] [Indexed: 02/01/2023]
Abstract
Docosahexaenoic acid (DHA) and arachidonic acid (AA) are found in high concentrations in brain cell membranes and are important for brain function and structure. Studies suggest that AA and DHA are hydrolyzed selectively from the sn-2 position of synaptic membrane phospholipids by Ca(2+)-dependent cytosolic phospholipase A(2) (cPLA(2)) and Ca(2+)-independent phospholipase A(2) (iPLA(2)), respectively, resulting in increased levels of the unesterified fatty acids and lysophospholipids. Cell studies also suggest that AA and DHA release depend on increased concentrations of Ca(2+), even though iPLA(2) has been thought to be Ca(2+)-independent. The source of Ca(2+) for activation of cPLA(2) is largely extracellular, whereas Ca(2+) released from the endoplasmic reticulum can activate iPLA(2) by a number of mechanisms. This review focuses on the role of Ca(2+) in modulating cPLA(2) and iPLA(2) activities in different conditions. Furthermore, a model is suggested in which neurotransmitters regulate the activity of these enzymes and thus the balanced and localized release of AA and DHA from phospholipid in the brain, depending on the primary source of the Ca(2+) signal.
Collapse
Affiliation(s)
- Angelo O Rosa
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892, USA.
| | | |
Collapse
|
33
|
|
34
|
Wada M, DeLong CJ, Hong YH, Rieke CJ, Song I, Sidhu RS, Yuan C, Warnock M, Schmaier AH, Yokoyama C, Smyth EM, Wilson SJ, FitzGerald GA, Garavito RM, Sui DX, Regan JW, Smith WL. Enzymes and receptors of prostaglandin pathways with arachidonic acid-derived versus eicosapentaenoic acid-derived substrates and products. J Biol Chem 2007; 282:22254-66. [PMID: 17519235 DOI: 10.1074/jbc.m703169200] [Citation(s) in RCA: 282] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Dietary fish oil containing omega 3 highly unsaturated fatty acids has cardioprotective and anti-inflammatory effects. Prostaglandins (PGs) and thromboxanes are produced in vivo both from the omega 6 fatty acid arachidonic acid (AA) and the omega 3 fatty acid eicosapentaenoic acid (EPA). Certain beneficial effects of fish oil may result from altered PG metabolism resulting from increases in the EPA/AA ratios of precursor phospholipids. Here we report in vitro specificities of prostanoid enzymes and receptors toward EPA-derived, 3-series versus AA-derived, 2-series prostanoid substrates and products. The largest difference was seen with PG endoperoxide H synthase (PGHS)-1. Under optimal conditions purified PGHS-1 oxygenates EPA with only 10% of the efficiency of AA, and EPA significantly inhibits AA oxygenation by PGHS-1. Two- to 3-fold higher activities or potencies with 2-series versus 3-series compounds were observed with PGHS-2, PGD synthases, microsomal PGE synthase-1 and EP1, EP2, EP3, and FP receptors. Our most surprising observation was that AA oxygenation by PGHS-2 is only modestly inhibited by EPA (i.e. PGHS-2 exhibits a marked preference for AA when EPA and AA are tested together). Also unexpectedly, TxA(3) is about equipotent to TxA(2) at the TP alpha receptor. Our biochemical data predict that increasing phospholipid EPA/AA ratios in cells would dampen prostanoid signaling with the largest effects being on PGHS-1 pathways involving PGD, PGE, and PGF. Production of 2-series prostanoids from AA by PGHS-2 would be expected to decrease in proportion to the compensatory decrease in the AA content of phospholipids that would result from increased incorporation of omega 3 fatty acids such as EPA.
Collapse
Affiliation(s)
- Masayuki Wada
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Rao JS, Ertley RN, DeMar JC, Rapoport SI, Bazinet RP, Lee HJ. Dietary n-3 PUFA deprivation alters expression of enzymes of the arachidonic and docosahexaenoic acid cascades in rat frontal cortex. Mol Psychiatry 2007; 12:151-7. [PMID: 16983392 DOI: 10.1038/sj.mp.4001887] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The enzymes that regulate the brain arachidonic acid (AA) cascade have been implicated in bipolar disorder and neuroinflammation. Fifteen weeks of dietary n-3 polyunsaturated fatty acid (PUFA) deprivation in rats decreases the concentration of docosahexaenoic acid (DHA) and increases its half-life within the brain. Based on this, we hypothesized that such dietary deprivation would decrease expression of enzymes responsible for the metabolic loss of DHA while increasing expression of those responsible for the metabolism of AA. Fifteen weeks of n-3 PUFA deprivation significantly decreased the activity, protein and mRNA expression of the DHA regulatory phospholipase A2 (PLA2), calcium-independent iPLA2, in rat frontal cortex. In contrast the activities, protein and mRNA levels of the AA selective calcium-dependent cytosolic phospholipase (cPLA2) and secretory sPLA2 were increased. Cyclooxygenase (COX)-1 protein but not mRNA was decreased in the n-3 PUFA-deprived rats whereas COX-2 protein and mRNA were increased. This study suggests that n-3 PUFA deprivation increases the half-live of brain DHA by downregulating iPLA2. The finding that n-3 PUFA deprivation increases cPLA2, sPLA2 and COX-2 is opposite to what has been reported after chronic administration of anti-manic agents to rats and suggests that n-3 PUFA deprivation may increase susceptibility to bipolar disorder.
Collapse
Affiliation(s)
- J S Rao
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892, USA.
| | | | | | | | | | | |
Collapse
|
36
|
Kishida E, Tajiri M, Masuzawa Y. Docosahexaenoic acid enrichment can reduce L929 cell necrosis induced by tumor necrosis factor. Biochim Biophys Acta Mol Cell Biol Lipids 2006; 1761:454-62. [PMID: 16698313 DOI: 10.1016/j.bbalip.2006.03.023] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2005] [Revised: 02/20/2006] [Accepted: 03/21/2006] [Indexed: 11/29/2022]
Abstract
We previously reported that docosahexaenoic acid (DHA) attenuated tumor necrosis factor (TNF)-induced apoptosis in human monocytic U937 cells (J. Nutr. 130: 1095-1101, 2000). In the present study, we examined the effects of DHA and other polyunsaturated fatty acids (PUFA) on TNF-induced necrosis, another mode of cell death, using L929 murine fibrosarcoma cells. After preincubation with PUFA conjugated with BSA for 24 h, cells were treated with TNF or TNF+actinomycin D (Act D). Preincubation of cells with DHA enriched this polyunsaturated acid in the phospholipids and attenuated cell death induced by either TNF or TNF+Act D. When cells were treated with TNF alone, DNA laddering was not detected, and cells were coincidently stained with both annexin V-FITC and propidium iodide, indicating that the death mode was necrotic. TNF+Act D predominantly induced necrosis, although concurrent apoptotic cell death was also observed in this case. Preincubation with oleic acid, linoleic acid or 20:3(n-3) did not affect TNF-induced necrosis. Conversely, supplementation with n-3 docosapentaenoic acid (DPAn-3) or eicosapentaenoic acid (EPA) reduced necrotic cell death, but to a lesser extent in comparison with DHA. Unlike the case of U937 cell apoptosis, arachidonic acid (AA) significantly attenuated L929 cell necrosis, and 20:3(n-6) or 22:4(n-6) showed similar or less activity, respectively. Statistical evaluation indicated that the order of effective PUFA activity was DHA>DPAn-3> or =EPA>AA approximately 20:3(n-6)> or =22:4(n-6). One step desaturation, C2 elongation or C2 cleavage within the n-6 or n-3 fatty acid group was probably very active in L929 cells, because AA, synthesized from 20:3(n-6) or 22:4(n-6), and C22 fatty acids, synthesized from AA or EPA, were preferentially retained in cellular phospholipids. These observations suggested that attenuation of TNF-induced necrosis by the supplementation of various C20 or C22 polyunsaturated fatty acids is mainly attributable to the enrichment of three kinds of polyunsaturated fatty acids, i.e., DHA, DPAn-3 or AA, in phospholipids. Among these fatty acids, DHA was the most effective in the reduction of L929 necrosis as observed in the case of U937 apoptosis. This suggests that DHA-enriched membranes can protect cell against TNF irrespective of death modes and that membranous DHA may abrogate the death signaling common to necrosis and apoptosis.
Collapse
Affiliation(s)
- Etsu Kishida
- Department of Life and Health Science, Hyogo University of Teacher Education, Yashiro, Hyogo 673-1494, Japan
| | | | | |
Collapse
|
37
|
McCabe AJ, Wallace JMW, Gilmore WS, McGlynn H, Strain SJ. Docosahexaenoic acid reduces in vitro invasion of renal cell carcinoma by elevated levels of tissue inhibitor of metalloproteinase-1. J Nutr Biochem 2005; 16:17-22. [PMID: 15629236 DOI: 10.1016/j.jnutbio.2004.07.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2004] [Revised: 06/16/2004] [Accepted: 07/21/2004] [Indexed: 11/18/2022]
Abstract
We demonstrate in this study that the n-3 polyunsaturated fatty acids derived from fish oil, namely, eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA), can increase levels of tissue inhibitors of metalloproteinase-1 (TIMP-1) in the renal cell carcinoma cell line caki-1 by 26% and 17.42% respectively. The result of this elevation in TIMP-1 levels is a reduction of 48.48% in caki-1 invasion through the basement membrane component matrigel when cells are treated with DHA. By inhibition of 2-series prostaglandin production, a similar increase in TIMP-1 was observed in caki-1 cells. We conclude that the polyunstaurated fatty acid DHA, a component of fish oil, is capable of significantly reducing the invasive profile of renal cell carcinoma, and that this reduction is regulated by levels of 2-series prostaglandin production.
Collapse
Affiliation(s)
- Anthony J McCabe
- Cancer and Aging Research Group, University of Ulster, Coleraine, UK.
| | | | | | | | | |
Collapse
|
38
|
Stafforini DM, McIntyre TM, Zimmerman GA, Prescott SM. Platelet-activating factor, a pleiotrophic mediator of physiological and pathological processes. Crit Rev Clin Lab Sci 2004; 40:643-72. [PMID: 14708958 DOI: 10.1080/714037693] [Citation(s) in RCA: 155] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Platelet-activating factor (PAF) is a potent proinflammatory phospholipid with diverse pathological and physiological effects. This bioactive phospholipid mediates processes as diverse as wound healing, physiological inflammation, apoptosis, angiogenesis, reproduction and long-term potentiation. Recent progress has demonstrated the participation of MAP kinase signaling pathways as modulators of the two critical enzymes, phospholipase A2 and acetyltransferase, involved in the remodeling pathway of PAF biosynthesis. The unregulated production of structural analogs of PAF by non-specific oxidative reactions has expanded this superfamily of signaling molecules to include "PAF-like" lipids whose mode of action is identical to that of authentic PAF. The action of members of this family is mediated by the PAF receptor, a G protein-coupled membrane-spanning molecule that can engage multiple signaling pathways in various cell types. Inappropriate activation of this signaling pathway is associated with many diseases in which inflammation is thought to be one of the underlying features. Inactivation of all members of the PAF superfamily occurs by a unique class of enzymes, the PAF acetylhydrolases, that have been characterized at the molecular level and that terminate signals initiated by both regulated and unregulated PAF production.
Collapse
Affiliation(s)
- Diana M Stafforini
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112-5550, USA.
| | | | | | | |
Collapse
|
39
|
Leslie CC. Regulation of the specific release of arachidonic acid by cytosolic phospholipase A2. Prostaglandins Leukot Essent Fatty Acids 2004; 70:373-6. [PMID: 15041029 DOI: 10.1016/j.plefa.2003.12.012] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/18/2003] [Indexed: 11/21/2022]
Abstract
Cytosolic phospholipase A(2) alpha (cPLA(2)alpha) is the only PLA(2) that exhibits specificity for sn-2 arachidonic acid consistent with its primary role in mediating the agonist-induced release of arachidonic acid for eicosanoid production. It is subject to complex mechanisms of regulation that ensure that levels of free arachidonic acid are tightly controlled. The calcium-induced translocation of cPLA(2)alpha from the cytosol to membrane regulates its interaction with phospholipid substrate. cPLA(2)alpha is additionally regulated by phosphorylation on sites in the catalytic domain. Because of its central position as the upstream regulatory enzyme for initiating production of several classes of bioactive lipid mediators (leukotrienes, prostaglandins and platelet-activating factor), it is a potentially important pharmacological target for the control of inflammatory diseases.
Collapse
Affiliation(s)
- Christina C Leslie
- Program in Cell Biology, Department of Pediatrics, National Jewish Medical and Research Center, 1400 Jackson St., Denver, CO 80206, USA.
| |
Collapse
|
40
|
Horrocks LA, Farooqui AA. Docosahexaenoic acid in the diet: its importance in maintenance and restoration of neural membrane function. Prostaglandins Leukot Essent Fatty Acids 2004; 70:361-72. [PMID: 15041028 DOI: 10.1016/j.plefa.2003.12.011] [Citation(s) in RCA: 200] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/18/2003] [Indexed: 11/30/2022]
Abstract
The central nervous system has the second highest concentration of lipids after adipose tissue. Long chain fatty acids, particularly arachidonic acid and docosahexaenoic acid, are integral components of neural membrane phospholipids. Alterations in neural membrane phospholipid components cannot only influence crucial intracellular and intercellular signaling but also alter many membrane physical properties such as fluidity, phase transition temperature, bilayer thickness, and lateral domains. A deficiency of docosahexaenoic acid markedly affects neurotransmission, membrane-bound enzyme and ion channel activities, gene expression, intensity of inflammation, and immunity and synaptic plasticity. Docosahexaenoic acid deficiency is associated with normal aging, Alzheimer disease, hyperactivity, schizophrenia, and peroxisomal disorders. Although the molecular mechanism of docosahexaenoic acid involvement in the disorders remains unknown, the supplementation of docosahexaenoic acid in the diet restores gene expression and modulates neurotransmission. Also, improvements are seen in signal transduction processes associated with behavioral deficits, learning activity, peroxisomal disorders, and psychotic changes in schizophrenia, depression, hyperactivity, stroke, and Alzheimer disease.
Collapse
Affiliation(s)
- Lloyd A Horrocks
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH 43210, USA.
| | | |
Collapse
|
41
|
Arita K, Yamamoto Y, Takehara Y, Utsumi T, Kanno T, Miyaguchi C, Akiyama J, Yoshioka T, Utsumi K. Mechanisms of enhanced apoptosis in HL-60 cells by UV-irradiated n-3 and n-6 polyunsaturated fatty acids. Free Radic Biol Med 2003; 35:189-99. [PMID: 12853075 DOI: 10.1016/s0891-5849(03)00310-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We examined the effects of arachidonic acid (AA), eicosapentaenoic acid (EPA), and their ultraviolet (UV)-irradiated products on HL-60 cells and isolated mitochondria to explore the following four obscure points in the mechanism of polyunsaturated fatty acids (PUFAs)-induced apoptosis: (i). the role of reactive oxygen species, (ii). the interaction of PUFAs and their metabolites with mitochondria in situ, (iii). the cyclosporine A (CsA)-sensitivity in PUFA-induced membrane permeability transition, (iv). the specificity of oxidized n-3 PUFAs in the induction of apoptosis in cancer cells. UV-oxidized PUFAs contained conjugated dienes and thiobarbituric acid reactive substances (TBARS). The apoptotic effects of PUFAs on HL-60 cells were increased by UV-irradiation whereas the swelling effect of PUFAs on isolated mitochondria was decreased. Both oxidized n-3 and n-6 PUFAs induced increased depolarization, ferricytochrome c release, the activation of various caspases, and DNA-fragmentation in a CsA-insensitive mechanism concomitant with a slight increase in the value of TBARS in cells. Furthermore, there were no significant differences in the mechanism of apoptosis induced by either oxidized AA or oxidized EPA. On the basis of these results, it was concluded that both oxidized n-3 or n-6 PUFAs induced apoptosis in HL-60 cells by a similar mechanism in a CsA-insensitive manner and also that oxidized products of PUFAs, but not the cellular oxidation process itself, play an important role in the mechanism of apoptosis in HL-60 cells.
Collapse
Affiliation(s)
- Kayo Arita
- Institute of Medical Science, Kurashiki Medical Center, Kurashiki, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Farooqui AA, Ong WY, Horrocks LA. Plasmalogens, Docosahexaenoic Acid and Neurological Disorders. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 544:335-54. [PMID: 14713251 DOI: 10.1007/978-1-4419-9072-3_45] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Affiliation(s)
- Akhlaq A Farooqui
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
| | | | | |
Collapse
|
43
|
Abstract
The first indication of platelet activation is an increase in mean platelet volume (MPV). n-3 FA are known to inhibit platelet function and to reduce the risk for coronary heart disease. The purpose of this study was to determine the effects of EPA and DHA on MPV. Healthy subjects received olive oil placebo for 4 wk and then were randomly assigned to receive 4 g of ethyl esters of either safflower oil (n = 11), EPA (n = 10), or DHA (n = 12) for 4 wk. At the end of placebo run-in and treatment periods, MPV (fL; mean +/- SEM) and platelet count (PLT-CT; 10(3)/microL blood) were measured in the basal state and after ex vivo stimulation with collagen (10 microg/mL), cold (4 degrees C), and heat (37 degrees C). Unlike DHA, EPA lowered MPV as compared with safflower oil (7.2 +/- 0.1 vs. 7.5 +/- 0.1 fL; P < 0.05) and raised PLT-CT (211 +/- 18 vs.192 +/- 18 10(3)/microL; P < 0.05) in the fasting state. Collagen and cold significantly increased MPV whereas heat lowered MPV regardless of treatment. All stimuli decreased PLT-CT. EPA significantly increased platelet EPA (0.2 +/- 0.1 vs. 3.3 +/- 0.4%) and docosapentaenoic acid (DPA; 2.2 +/- 0.3 vs. 2.9 +/- 0.3%) concentrations, but not DHA. DHA treatment significantly increased DHA (1.4 +/- 0.2 vs. 4.1 +/- 0.5%) and DPA (2.0 +/- 0.4 vs. 3.0 +/- 0.4%) concentrations, but not EPA. In conclusion, EPA, but not DHA, reduces platelet activation, an early step in platelet aggregation.
Collapse
Affiliation(s)
- Yongsoon Park
- Department of Medicine, University of Missouri-Kansas City, Missouri 64108, USA
| | | |
Collapse
|
44
|
Ge Y, Wang X, Chen Z, Landman N, Lo EH, Kang JX. Gene transfer of the Caenorhabditis elegans n-3 fatty acid desaturase inhibits neuronal apoptosis. J Neurochem 2002; 82:1360-6. [PMID: 12354283 DOI: 10.1046/j.1471-4159.2002.01077.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Previous studies have shown that n-3 polyunsaturated fatty acids (PUFAs) can exert an antiapoptotic effect on neurons. The present study was designed to investigate whether the Caenorhabditis elegans fat-1 gene encoding an n-3 fatty acid desaturase (an enzyme that converts n-6 PUFAs to corresponding n-3 PUFAs) can be expressed functionally in rat cortical neurons and whether its expression can change the ratio of n-6 : n-3 fatty acids in the cell membrane and exert an effect on neuronal apoptosis. Infection of primary rat cortical cultures with Ad-fat-1 resulted in high expression of the fat-1 gene. Lipid analysis indicated a decrease in the ratio of n-6 : n-3 PUFAs from 5.9 : 1 in control cells, to 1.45 : 1 in cells expressing the n-3 fatty acid desaturase. Accordingly, the levels of prostaglandin E2, an eicosanoid derived from n-6 PUFA, were significantly lower in cells infected with Ad-fat-1 when compared with control cells. Finally, there was a significant inhibition of growth factor withdrawal-induced apoptotic cell death in neurons expressing the fat-1 gene. These results demonstrate that expression of the fat-1 gene can inhibit apoptotic cell death in neurons and suggest that the change in the n-6 : n-3 fatty acid ratio may play a key role in this protective effect.
Collapse
Affiliation(s)
- Yinlin Ge
- Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | | | | | | | | | | |
Collapse
|
45
|
Chapter 8 Molecular species of phospholipids during brain development. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s0167-7306(02)35037-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
46
|
Contreras MA, Chang MC, Rosenberger TA, Greiner RS, Myers CS, Salem N, Rapoport SI. Chronic nutritional deprivation of n-3 alpha-linolenic acid does not affect n-6 arachidonic acid recycling within brain phospholipids of awake rats. J Neurochem 2001; 79:1090-9. [PMID: 11739623 DOI: 10.1046/j.1471-4159.2001.00658.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Using an in vivo fatty acid model and operational equations, we reported that esterified and unesterified concentrations of docosahexaenoic acid (DHA, 22 : 6 n-3) were markedly reduced in brains of third-generation (F3) rats nutritionally deprived of alpha-linolenic acid (18 : 3 n-3), and that DHA turnover within phospholipids was reduced as well. The concentration of docosapentaenoic acid (DPA, 22 : 5 n-6), an arachidonic acid (AA, 20 : 4 n-6) elongation/desaturation product, was barely detectable in control rats but was elevated in the deprived rats. In the present study, we used the same in vivo model, involving the intravenous infusion of radiolabeled AA to demonstrate that concentrations of unesterified and esterified AA, and turnover of AA within phospholipids, were not altered in brains of awake F3-generation n-3-deficient rats, compared with control concentrations. Brain DPA-CoA could be measured in the deprived but not control rats, and AA-CoA was elevated in the deprived animals. These results indicated that AA and DHA are recycled within brain phospholipids independently of each other, suggesting that recycling is regulated independently by AA- and DHA-selective enzymes, respectively. Competition among n-3 and n-6 fatty acids within brain probably does not occur at the level of recycling, but at levels of elongation and desaturation (hence greater production of DPA during n-3 deprivation), or conversion to bioactive eicosanoids and other metabolites.
Collapse
Affiliation(s)
- M A Contreras
- Brain Physiology and Metabolism Section, National Institute on Aging, NIH, Bethesda, Maryland 20892, USA
| | | | | | | | | | | | | |
Collapse
|
47
|
Kuroda Y, Shima N, Yazawa K, Kaji K. Desmutagenic and bio-antimutagenic activity of docosahexaenoic acid and eicosapentaenoic acid in cultured Chinese hamster V79 cells. Mutat Res 2001; 497:123-30. [PMID: 11525914 DOI: 10.1016/s1383-5718(01)00247-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The antimutagenic activities of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were examined by studying their effects on induction of 6-thioguanine (6TG)-resistant mutations by ethyl methanesulfonate (EMS) in cultured Chinese hamster V79 cells. DRA had a remarkable inhibitory effect against the cytotoxicity of EMS, when cells were simultaneously-treated with EMS, showing a blocking or scavenging activity of DHA in reduction of surviving fraction of cells. DHA had not so significant effect, when cells were treated before and after treatment with EMS. On the other hand, EPA had marked inhibiting effects against cytotoxicity of EMS, when cells were treated with EPA, before, simultaneous and after treatment with EMS. Against the induction of mutations by EMS, an antimutagenic activity of DHA was found when cells were pre-treated, simultaneously-treated or post-treated with DHA. EPA was also effective in reducing EMS-induced 6TG-resistant mutations when the cells were treated using the three different treatment procedures described above. The results suggest that in cultured Chinese hamster V79 cells, DHA and EPA may have both desmutagenic activity, which inactivates EMS chemically and/or enzymatically and bio-antimutagenic activity which suppresses mutation fixation after DNA is damaged by EMS.
Collapse
Affiliation(s)
- Y Kuroda
- National Institute of Genetics, Mishima, 411-8540, Shizuoka, Japan.
| | | | | | | |
Collapse
|
48
|
Watanabe S, Doshi M, Akimoto K, Kiso Y, Hamazaki T. Suppression of platelet-activating factor generation and modulation of arachidonate metabolism by dietary enrichment with (n-9) eicosatrienoic acid or docosahexaenoic acid in mouse peritoneal cells. Prostaglandins Other Lipid Mediat 2001; 66:109-20. [PMID: 11534547 DOI: 10.1016/s0090-6980(01)00152-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Several studies have shown that dietary n-3 polyunsaturated fatty acids (PUFAs) suppress platelet-activating factor (PAF) generation in leukocytes of humans and rodents, which is associated with the antagonism of arachidonic acid metabolism. Dietary eicosatrienoic acid (20:3n-9, ETrA) is also suggested to antagonize arachidonic acid (AA) metabolism, but its effect on PAF generation in leukocytes has not been defined. In the present study, we investigated the effects of an ETrA-rich diet on PAF generation and AA metabolism in mouse peritoneal cells, which were compared with those of a docosahexaenoic acid (DHA)-rich diet. Mice were fed a diet supplemented with a lipid preparation rich in ETrA, a DHA-rich fish oil (FO) or palm oil (PO) for 3 weeks, and peritoneal cells containing more than 80% of monocytes/macrophages were obtained. The peritoneal cells in the DHA and ETrA diet groups generated upon zymosan stimulation a smaller amount of PAF than cells in the PO diet group. In the peritoneal cells of the DHA diet group, AA contents in phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were significantly lower than those in cells of the PO diet group, but those in phosphatidylinositol (PI) were not significantly different between the two dietary groups. A considerable amount of ETrA was incorporated into the peritoneal cells of the ETrA diet group, and AA was reduced as compared with the PO diet group. These changes occurred preferentially in PI but to a less extent in PC and PE. The amount of free AA released by the peritoneal cells upon zymosan stimulation was significantly reduced in the DHA diet group as compared with that in the PO diet group, whereas AA release was similar between the PO and ETrA diet groups. In conclusion, the effects of dietary ETrA on AA content in the phospholipid subclasses and AA release were quite different from those of dietary DHA, although both diets suppressed PAF generation in mouse peritoneal cells to a similar extent.
Collapse
Affiliation(s)
- S Watanabe
- Department of Clinical Application, Toyama Medical and Pharmaceutical University, Japan.
| | | | | | | | | |
Collapse
|
49
|
Hii CS, Moghadammi N, Dunbar A, Ferrante A. Activation of the Phosphatidylinositol 3-Kinase-Akt/Protein Kinase B Signaling Pathway in Arachidonic Acid-stimulated Human Myeloid and Endothelial Cells. J Biol Chem 2001; 276:27246-55. [PMID: 11359783 DOI: 10.1074/jbc.m103250200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although arachidonic acid has been demonstrated to stimulate a wide variety of cellular functions, the responsible mechanisms remain poorly defined. We now report that arachidonic acid stimulated the activity of class Ia phosphatidylinositol 3-kinase (PI3K) in human umbilical vein endothelial cells, HL60 cells, and human neutrophils. Pretreatment of endothelial cells with AG-1478, an inhibitor of the ErbB receptor family, resulted in the suppression of PI3K activation by arachidonic acid. The fatty acid enhanced the tyrosine phosphorylation of ErbB4 but not of ErbB2 or ErbB3. The ability of arachidonic acid to stimulate PI3K activity in neutrophils was suppressed by indomethacin and nordihydroguaiaretic acid, inhibitors of the cyclooxygenases and lipoxygenases, respectively, but not by 17-octadecynoic acid, an inhibitor of omega-hydroxylation of arachidonic acid by cytochrome P450 monooxygenases. Consistent with this, the activity of PI3K in neutrophils was stimulated by 5-hydroxyeicosatetraenoic acid. Arachidonic acid also transiently stimulated the phosphorylation of Akt on Thr-308 and Ser-473. Although PI3K was not required for the activation of the mitogen-activated protein kinases, ERK1, ERK2, and p38, in arachidonic acid-stimulated neutrophils, the fatty acid acted via PI3K to stimulate the respiratory burst. These results not only define a novel mechanism through which some of the actions of arachidonic acid are mediated but also demonstrate that, in addition to ErbB1 (epidermal growth factor receptor), ErbB4 can also be transactivated by a non-epidermal growth factor-like ligand.
Collapse
Affiliation(s)
- C S Hii
- Department of Immunopathology, Women's and Children's Hospital, North Adelaide 5006, South Australia.
| | | | | | | |
Collapse
|
50
|
Farooqui AA, Horrocks LA. Plasmalogens, phospholipase A2, and docosahexaenoic acid turnover in brain tissue. J Mol Neurosci 2001; 16:263-72; discussion 279-84. [PMID: 11478381 DOI: 10.1385/jmn:16:2-3:263] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Plasmalogens are glycerophospholipids of neural membranes containing vinyl ether bonds. Their synthetic pathway is located in peroxisomes and endoplasmic reticulum. The rate-limiting enzymes are in the peroxisomes and are induced by docosahexaenoic acid (DHA). Plasmalogens often contain arachidonic acid (AA) or DHA at the sn-2 position of the glycerol moiety. The receptor-mediated hydrolysis of plasmalogens by cytosolic plasmalogen-selective phospholipase A2 generates AA or DHA and lysoplasmalogens. AA is metabolized to eicosanoids. The mechanism of signaling with DHA is not known. The plasmalogen-selective phospholipase A2 differs from other intracellular phospholipases A2 in molecular mass, kinetic properties, substrate specificity, and response to glycosaminoglycans, gangliosides, and sialoglycoproteins. A major portion of [3H]DHA incorporated into neural membranes is found at the sn-2 position of ethanolamine glycerophospholipids. Studies with a mutant cell line defective in plasmalogen biosynthesis indicate that the incorporation of DHA is reduced in this RAW 264.7 cell line by 50%. In contrast, the incorporation of AA remains unaffected. This is reversed completely when the growth medium is supplemented with sn-1-hexadecylglycerol, suggesting that DHA can be selectively targeted for incorporation into plasmalogens. We suggest that deficiencies of DHA and plasmalogens in peroxisomal disorders, Alzheimer's disease (AD), depression, and attention deficit hyperactivity disorders (ADHD) may be responsible for abnormal signal transduction associated with learning disability, cognitive deficit, and visual dysfunction. These abnormalities in the signal-transduction process can be partially corrected by supplementation with a diet enriched with DHA.
Collapse
Affiliation(s)
- A A Farooqui
- Department of Molecular and Cellular Biochemistry The Ohio State University, Columbus 43210, USA
| | | |
Collapse
|