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Andries A, Rozenski J, Vermeersch P, Mekahli D, Van Schepdael A. Recent progress in the LC-MS/MS analysis of oxidative stress biomarkers. Electrophoresis 2020; 42:402-428. [PMID: 33280143 DOI: 10.1002/elps.202000208] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 11/17/2020] [Accepted: 11/30/2020] [Indexed: 12/12/2022]
Abstract
The presence of a dynamic and balanced equilibrium between the production of reactive oxygen (ROS) and nitrogen (RNS) species and the in-house antioxidant defense mechanisms is characteristic for a healthy body. During oxidative stress (OS), this balance is switched to increased production of ROS and RNS, exceeding the capacity of physiological antioxidant systems. This can cause damage to biological molecules, leading to loss of function and even cell death. Nowadays, there is increasing scientific and clinical interest in OS and the associated parameters to measure the degree of OS in biofluids. An increasing number of reports using LC-MS/MS methods for the analysis of OS biomarkers can be found. Since bioanalysis is usually complicated by matrix effects, various types of cleanup procedures are used to effectively separate the biomarkers from the matrix. This is an essential part of the analysis to prepare a reproducible and homogenous solution suitable for injection onto the column. The present review gives a summary of the chromatographic methods used for the determination of OS biomarkers in both urine and plasma, serum, and whole blood samples. The first part mainly describes the biological background of the different OS biomarkers, while the second part reports examples of chromatographic methods for the analysis of different metabolites connected with OS in biofluids, covering a period from 2015 till early 2020. The selected examples mainly include LC-MS/MS methods for isoprostanes, oxidized proteins, oxidized lipoproteins, and DNA/RNA biomarkers. The last part explains the clinical relevance of this review.
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Affiliation(s)
- Asmin Andries
- Department of Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, KU Leuven - University of Leuven, Leuven, Belgium
| | - Jef Rozenski
- KU Leuven - Rega Institute for Medical Research, Medicinal Chemistry, Leuven, Belgium
| | - Pieter Vermeersch
- Clinical Department of Laboratory Medicine, University Hospitals Leuven, Leuven, Belgium.,Center for Metabolic Diseases, University Hospitals Leuven, Leuven, Belgium
| | - Djalila Mekahli
- Department of Development and Regeneration, Laboratory of Pediatrics, PKD group, KU Leuven - University of Leuven, Leuven, Belgium.,Department of Pediatric Nephrology, University Hospitals Leuven, Leuven, Belgium
| | - Ann Van Schepdael
- Department of Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, KU Leuven - University of Leuven, Leuven, Belgium
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2
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Serbulea V, DeWeese D, Leitinger N. The effect of oxidized phospholipids on phenotypic polarization and function of macrophages. Free Radic Biol Med 2017; 111:156-168. [PMID: 28232205 PMCID: PMC5511074 DOI: 10.1016/j.freeradbiomed.2017.02.035] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 02/09/2017] [Accepted: 02/15/2017] [Indexed: 12/26/2022]
Abstract
Oxidized phospholipids are products of lipid oxidation that are found on oxidized low-density lipoproteins and apoptotic cell membranes. These biologically active lipids were shown to affect a variety of cell types and attributed pro-as well as anti-inflammatory effects. In particular, macrophages exposed to oxidized phospholipids drastically change their gene expression pattern and function. These 'Mox,'macrophages were identified in atherosclerotic lesions, however, it remains unclear how lipid oxidation products are sensed by macrophages and how they influence their biological function. Here, we review recent developments in the field that provide insight into the structure, recognition, and downstream signaling of oxidized phospholipids in macrophages.
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Affiliation(s)
- Vlad Serbulea
- Robert M. Berne Cardiovascular Research Center and Department of Pharmacology, University of Virginia, USA
| | - Dory DeWeese
- Robert M. Berne Cardiovascular Research Center and Department of Pharmacology, University of Virginia, USA
| | - Norbert Leitinger
- Robert M. Berne Cardiovascular Research Center and Department of Pharmacology, University of Virginia, USA
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3
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Koller D, Hackl H, Bogner-Strauß JG, Hermetter A. Effects of oxidized phospholipids on gene expression in RAW 264.7 macrophages: a microarray study. PLoS One 2014; 9:e110486. [PMID: 25333283 PMCID: PMC4204898 DOI: 10.1371/journal.pone.0110486] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 09/10/2014] [Indexed: 01/09/2023] Open
Abstract
Oxidized phospholipids (oxPLs) are components of oxidized LDL (oxLDL). It is known that oxLDL activates expression of a series of atherogenic genes and their oxPLs contribute to their biological activities. In this study we present the effects of 1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphocholine (PGPC) and 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC) on gene expression in RAW 264.7 macrophages using cDNA microarrays. PGPC affected the regulation of 146 genes, whereas POVPC showed only very minor effects. PGPC preferentially influenced expression of genes related to cell death, angiogenesis, cholesterol efflux, procoagulant mechanisms, atherogenesis, inflammation, and cell cycle. Many of these effects are known from studies with oxLDL or oxidized 1-hexadecanoyl-2-eicosatetra-5′,8′,11′,14′-enoyl-sn-glycero-3-phosphocholine (oxPAPC), containing PGPC in addition to other oxPL species. It is known that POVPC efficiently reacts with proteins by Schiff base formation, whereas PGPC only physically interacts with its biological targets. POVPC seems to affect cell physiology to a great extent on the protein level, whereas PGPC gives rise to both the modulation of protein function and regulation on the transcriptional level.
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Affiliation(s)
- Daniel Koller
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
| | - Hubert Hackl
- Biocenter, Division of Bioinformatics, Innsbruck Medical University, Innsbruck, Austria
| | | | - Albin Hermetter
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
- * E-mail:
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4
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Haller E, Stübiger G, Lafitte D, Lindner W, Lämmerhofer M. Chemical Recognition of Oxidation-Specific Epitopes in Low-Density Lipoproteins by a Nanoparticle Based Concept for Trapping, Enrichment, and Liquid Chromatography–Tandem Mass Spectrometry Analysis of Oxidative Stress Biomarkers. Anal Chem 2014; 86:9954-61. [DOI: 10.1021/ac502855n] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Elisabeth Haller
- Department
of Analytical Chemistry, University of Vienna, Währingerstrasse 38, 1090 Vienna, Austria
| | - Gerald Stübiger
- Center
of Physiology and Pharmacology, Medical University of Vienna, Schwarzspanierstraße 17, 1090 Vienna, Austria
| | - Daniel Lafitte
- Faculté
de Pharmacie de Marseille, Université de Marseille, 27 Boulevard
Jean Moulin, CS 30064−13385 Marseille, Cedex 5 France
| | - Wolfgang Lindner
- Department
of Analytical Chemistry, University of Vienna, Währingerstrasse 38, 1090 Vienna, Austria
| | - Michael Lämmerhofer
- Institute
of Pharmaceutical Sciences, Pharmaceutical (Bio)Analysis, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany
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Rao X, Zhong J, Maiseyeu A, Gopalakrishnan B, Villamena FA, Chen LC, Harkema JR, Sun Q, Rajagopalan S. CD36-dependent 7-ketocholesterol accumulation in macrophages mediates progression of atherosclerosis in response to chronic air pollution exposure. Circ Res 2014; 115:770-780. [PMID: 25186795 DOI: 10.1161/circresaha.115.304666] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
RATIONALE Air pollution exposure has been shown to potentiate plaque progression in humans and animals. Our previous studies have suggested a role for oxidized lipids in mediating adverse vascular effect of air pollution. However, the types of oxidized lipids formed in response to air pollutants and how this occurs and their relevance to atherosclerosis are not fully understood. OBJECTIVE To investigate the mechanisms by which particulate matter <2.5 μm (PM2.5) induces progression of atherosclerosis. METHODS AND RESULTS Atherosclerosis-prone ApoE(-/-) or LDLR(-/-) mice were exposed to filtered air or concentrated ambient PM2.5 using a versatile aerosol concentrator enrichment system for 6 months. PM2.5 increased 7-ketocholesterol (7-KCh), an oxidatively modified form of cholesterol, in plasma intermediate density lipoprotein/low-density lipoprotein fraction and in aortic plaque concomitant with progression of atherosclerosis and increased CD36 expression in plaque macrophages from PM2.5-exposed mice. Macrophages isolated from PM2.5-exposed mice displayed increased uptake of oxidized lipids without alterations in their efflux capacity. Consistent with these finding, CD36-positive macrophages displayed a heightened capacity for oxidized lipid uptake. Deficiency of CD36 on hematopoietic cells diminished the effect of air pollution on 7-KCh accumulation, foam cell formation, and atherosclerosis. CONCLUSIONS Our results suggest a potential role for CD36-mediated abnormal accumulations of oxidized lipids, such as 7-KCh, in air pollution-induced atherosclerosis progression.
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Affiliation(s)
- Xiaoquan Rao
- Division of Cardiovascular Medicine, University of Maryland Baltimore, Maryland, USA
| | - Jixin Zhong
- Division of Cardiovascular Medicine, University of Maryland Baltimore, Maryland, USA
| | - Andrei Maiseyeu
- Division of Cardiovascular Medicine, University of Maryland Baltimore, Maryland, USA
| | - Bhavani Gopalakrishnan
- Department of Pharmacology, Davis Heart & Lung Research Institute, The Ohio State University, Columbus, Ohio, USA
| | - Frederick A Villamena
- Department of Pharmacology, Davis Heart & Lung Research Institute, The Ohio State University, Columbus, Ohio, USA
| | - Lung-Chi Chen
- The Department of Environmental Medicine, New York University School of Medicine, Tuxedo, New York, USA
| | - Jack R Harkema
- Center for Integrative Toxicology and Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, Michigan, USA
| | - Qinghua Sun
- Department of Pharmacology, Davis Heart & Lung Research Institute, The Ohio State University, Columbus, Ohio, USA.,College of Public Health, The Ohio State University, Columbus, Ohio, USA
| | - Sanjay Rajagopalan
- Division of Cardiovascular Medicine, University of Maryland Baltimore, Maryland, USA
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Atherogenic mononuclear cell recruitment is facilitated by oxidized lipoprotein-induced endothelial junctional adhesion molecule-A redistribution. Atherosclerosis 2014; 234:254-64. [PMID: 24704627 DOI: 10.1016/j.atherosclerosis.2014.03.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 02/28/2014] [Accepted: 03/13/2014] [Indexed: 02/02/2023]
Abstract
BACKGROUND Junctional adhesion molecule (JAM-) A is a transmembrane protein expressed in many cell types and maintains junctional integrity in endothelial cells. Upon inflammatory stimulation, JAM-A relocates to the apical surface and might thereby facilitate the recruitment of leukocytes. OBJECTIVE Although inflammatory JAM-A redistribution is an established process, further effort is required to understand its exact role in the transmigration of mononuclear cells, particularly under atherogenic conditions. METHODS By the use of RNA interference and genetic deletion, the role of JAM-A in the transmigration of T cells and monocytes through aortic endothelial cells was investigated. JAM-A-localization and subsequent mononuclear cell rolling, adhesion and transmigration were explored during endothelial inflammation, induced by oxidized LDL or cytokines. RESULTS RNA interference or genetic deletion of JAM-A in aortic endothelial cells resulted in a decreased transmigration of mononuclear cells. Treatment of the endothelial cells with oxLDL resulted in an increase of both permeability and apical JAM-A presentation, as shown by bead adhesion and confocal microscopy experiments. Redistribution of JAM-A resulted in an increased leukocyte adhesion and transmigration, which could be inhibited with antibodies against JAM-A or by lovastatin-treatment, but not with the peroxisome proliferator activated receptor gamma-agonist pioglitazone. CONCLUSIONS This study demonstrates that redistribution of JAM-A in endothelial cells after stimulation with pro-atherogenic oxidized lipoproteins results in increased transmigration of mononuclear cells. This inflammatory dispersal of JAM-A could be counteracted with statins, revealing a novel aspect of their mechanism of action.
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7
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Minimally modified low-density lipoprotein induces macrophage endoplasmic reticulum stress via toll-like receptor 4. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:954-63. [PMID: 22480542 DOI: 10.1016/j.bbalip.2012.03.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 03/06/2012] [Accepted: 03/12/2012] [Indexed: 01/21/2023]
Abstract
Minimally modified low-density lipoprotein (mm-LDL) induces intimal foam cell formation, which is promoted by endoplasmic reticulum stress (ERS), a cross-point to link cellular processes with multiple risk factors that exist in all stages of atherosclerosis. However, it remains unclear whether mm-LDL-induced lipid accumulation in macrophages involves ERS and its underlying mechanisms. We showed that mm-LDL induced the accumulation of lipid droplets in RAW264.7 macrophages with increased free cholesterol in the endoplasmic reticulum, which was markedly attenuated by pretreatment with an antibody against toll-like receptor 4 (TLR4). Additionally, mm-LDL stimulated the transport of Cy3-labeled activating transcription factor 6 (ATF6), a key sensor to the unfolded protein response (UPR), from cytoplasm into nucleus. The expression of phosphorylated inositol-requiring enzyme 1 (p-IRE1), another sensor to the UPR, and its two downstream molecules, X box binding protein 1 and glucose-regulated protein 78 (GRP78), were significantly upregulated by mm-LDL. The alterations induced by mm-LDL were all significantly inhibited by antibodies against TLR4 or CD36. In addition, the upregulation of p-IRE1 and GRP78 and the nuclear translocation of ATF6 induced by mm-LDL were significantly attenuated by TLR4 siRNA. These results suggest that mm-LDL may induce free cholesterol accumulation in the endoplasmic reticulum and subsequently stimulate ERS and activate the UPR signaling pathway mediated by ATF6 and IRE1 in macrophages, a process that is potentially mediated by TLR4.
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Usatyuk PV, Natarajan V. Hydroxyalkenals and oxidized phospholipids modulation of endothelial cytoskeleton, focal adhesion and adherens junction proteins in regulating endothelial barrier function. Microvasc Res 2012; 83:45-55. [PMID: 21570987 PMCID: PMC3196796 DOI: 10.1016/j.mvr.2011.04.012] [Citation(s) in RCA: 217] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 04/27/2011] [Accepted: 04/28/2011] [Indexed: 10/18/2022]
Abstract
Lipid peroxidation of polyunsaturated fatty acids generates bioactive aldehydes, which exhibit pro- and anti-inflammatory effects in cells and tissues. Accumulating evidence indicates that 4-hydroxynonenal (4-HNE), a major aldehyde derived from lipid peroxidation of n-6 polyunsaturated fatty acids trigger signals that modulates focal adhesion and adherens junction proteins thereby inducing endothelial barrier dysfunction. Similarly, oxidized phospholipids (Ox-PLs) generated by lipid peroxidation of phospholipids with polyunsaturated fatty acids have been implicated in atherogenesis, inflammation and gene expression. Interestingly, physiological concentration of Ox-PLs is anti-inflammatory and protect against endotoxin- and ventilator-associated acute lung injury. Thus, excess generation of bioactive hydroxyalkenals and Ox-PLs during oxidative stress contributes to pathophysiology of various diseases by modulating signaling pathways that regulate pro- and anti-inflammatory responses and barrier regulation. This review summarizes the role of 4-HNE and Ox-PLs affecting cell signaling pathways and endothelial barrier dysfunction through modulation of the activities of proteins/enzymes by Michael adducts formation, enhancing the level of protein tyrosine phosphorylation of the target proteins, and by reorganization of cytoskeletal, focal adhesion, and adherens junction proteins. A better understanding of molecular mechanisms of hydroxyalkenals- and Ox-PLs-mediated pro-and anti-inflammatory responses and barrier function may lead to development of novel therapies to ameliorate oxidative stress related cardio-pulmonary disorders.
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Affiliation(s)
- Peter V. Usatyuk
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612
- Institute for Personalized Respiratory Medicine, University of Illinois at Chicago, Chicago, IL 60612
| | - Viswanathan Natarajan
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612
- Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612
- Institute for Personalized Respiratory Medicine, University of Illinois at Chicago, Chicago, IL 60612
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Hammond VJ, O'Donnell VB. Esterified eicosanoids: generation, characterization and function. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1818:2403-12. [PMID: 22200400 DOI: 10.1016/j.bbamem.2011.12.013] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Revised: 11/28/2011] [Accepted: 12/11/2011] [Indexed: 12/20/2022]
Abstract
Eicosanoids are oxidation products of C20 polyunsaturated fatty acids (e.g. arachidonic acid) that include prostaglandins, thromboxanes, leukotrienes and hydroperoxy fatty acids. They have important biological roles in vivo, including regulation of renal, cardiovascular and gastrointestinal function. Historically, eicosanoids were thought to mediate their signaling actions exclusively as free acids, however evidence is now emerging that they may also be generated attached to other functional groups including phospholipids and glycerol, and that these more complex forms are pathophysiological signaling mediators in their own right. Early studies showed that exogenously added eicosanoids could become esterified into membrane phospholipids of cells, while more recently, it was uncovered that esterified eicosanoids are formed endogenously. This review summarizes our current knowledge of this area, starting with the early discoveries documenting what is known about eicosanoid generation and their esterification, and moving on to discuss the discovery that esterified eicosanoids are generated endogenously by a number of different cell types. Recent research that is highlighting new structures and functions of these important lipid mediators will be presented. This article is part of a Special Issue entitled: Oxidized phospholipids-their properties and interactions with proteins.
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Abstract
Platelets shed microparticles not only upon activation, but also upon ageing by an apoptosis-like process (apoptosis-induced platelet microparticles, PMap). While the activation-induced microparticles have widely been studied, not much is known about the (patho)physiological consequences of PMap formation. Flow cytometry and scanning electron microscopy demonstrated that PMap display activated integrins and interact to form microparticle aggregates. PMap were chemotactic for monocytic cells, bound to these cells, an furthermore stimulated cell adhesion and spreading on a fibronectin surface. After prolonged incubation, PMap promoted cell differentiation, but inhibited proliferation. Monocyte membrane receptor analysis revealed increased expression levels of CD11b (integrin αMβ2), CD14 and CD31 (platelet endothelial cell adhesion molecule-1), and the chemokine receptors CCR5 and CXCR4, but not of CCR2. This indicated that PMap polarized the cells into resident M2 monocytes. Cells treated with PMap actively consumed oxidized low-density lipoprotein (oxLDL), and released matrix metalloproteinases and hydrogen peroxide. Further confirmation for the differentiation towards resident professional phagocytes came from the finding that PMap stimulated the expression of the (ox)LDL receptors, CD36 and CD68, and the production of proinflammatory and immunomodulating cytokines by monocytes. In conclusion, interaction of PMap with monocytic cells has an immunomodulating potential. The apoptotic microparticles polarize the cells into a resident M2 subset, and induce differentiation to resident professional phagocytes.
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Bochkov VN, Oskolkova OV, Birukov KG, Levonen AL, Binder CJ, Stöckl J. Generation and biological activities of oxidized phospholipids. Antioxid Redox Signal 2010; 12:1009-59. [PMID: 19686040 PMCID: PMC3121779 DOI: 10.1089/ars.2009.2597] [Citation(s) in RCA: 403] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Glycerophospholipids represent a common class of lipids critically important for integrity of cellular membranes. Oxidation of esterified unsaturated fatty acids dramatically changes biological activities of phospholipids. Apart from impairment of their structural function, oxidation makes oxidized phospholipids (OxPLs) markers of "modified-self" type that are recognized by soluble and cell-associated receptors of innate immunity, including scavenger receptors, natural (germ line-encoded) antibodies, and C-reactive protein, thus directing removal of senescent and apoptotic cells or oxidized lipoproteins. In addition, OxPLs acquire novel biological activities not characteristic of their unoxidized precursors, including the ability to regulate innate and adaptive immune responses. Effects of OxPLs described in vitro and in vivo suggest their potential relevance in different pathologies, including atherosclerosis, acute inflammation, lung injury, and many other conditions. This review summarizes current knowledge on the mechanisms of formation, structures, and biological activities of OxPLs. Furthermore, potential applications of OxPLs as disease biomarkers, as well as experimental therapies targeting OxPLs, are described, providing a broad overview of an emerging class of lipid mediators.
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Affiliation(s)
- Valery N Bochkov
- Department of Vascular Biology and Thrombosis Research, Center for Biomolecular Medicine and Pharmacology, Medical University of Vienna, Vienna, Austria.
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Berliner JA, Leitinger N, Tsimikas S. The role of oxidized phospholipids in atherosclerosis. J Lipid Res 2008; 50 Suppl:S207-12. [PMID: 19059906 DOI: 10.1194/jlr.r800074-jlr200] [Citation(s) in RCA: 164] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
There is increasing evidence that oxidized phospholipids (OxPLs) play an important role in atherosclerosis. These phospholipids accumulate in human and mouse lesions. Specific OxPLs have been identified as major regulators of many cell types present in the vessel wall. In endothelial cells, >1,000 genes are regulated. Some of these genes are pro-atherogenic and others anti-atherogenic. The anti-atherogenic effects are likely important in slowing the atherogenic process. Several receptors and signaling pathways associated with OxPL action have been identified and shown to be upregulated in human lesions. A structural model of the mechanism by which specific OxPLs serve as CD36 ligands has been identified. Specific oxidized phospholipids are also present in plasma and associated with Lp(a) particles. In humans, OxPL/apolipoprotein B has been shown to be a prognostic indicator and a separate risk factor for coronary events. Levels of OxPL in plasma have been shown to be correlated with platelet activation. The results of these studies suggest an important role for OxPL in all stages of atherosclerosis.
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Affiliation(s)
- Judith A Berliner
- Department of Pathology, University of California, Los Angeles, CA, USA.
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