1
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Detopoulou P, Fragopoulou E, Nomikos T, Antonopoulou S. Associations of phase angle with platelet-activating factor metabolism and related dietary factors in healthy volunteers. Front Nutr 2023; 10:1237086. [PMID: 38024339 PMCID: PMC10655008 DOI: 10.3389/fnut.2023.1237086] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 10/09/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction Phase angle (PA) is derived from bioelectrical impedance analysis (BIA). It reflects cell membrane function and decreases in disease. It is affected by inflammation, oxidative stress, and diet. Platelet-activating factor (PAF) is a potent inflammatory lipid mediator. Its levels, along with the activity of its metabolic enzymes, including CDP-choline:1-alkyl-2-acetyl-sn-glycerol-cholinephosphotransferase, acetyl-CoA:lyso-PAF-acetyltransferases, and PAF-AH/Lp-PLA2 are also related to dietary factors, such as the dietary antioxidant capacity (DAC). The aim of the study was to estimate whether the PAF metabolic circuit and related dietary factors are associated with PA in healthy volunteers. Methods In healthy subjects, PAF, its metabolic enzyme activity, and erythrocyte fatty acids were measured, while desaturases were estimated. Food-frequency questionnaires and recalls were used, and food groups, macronutrient intake, MedDietScore, and DAC were assessed. Lifestyle and biochemical variables were collected. DXA and BIA measurements were performed. Results Lp-PLA2 activity was positively associated with PA (rho = 0.651, p < 0.001, total population; rho = 0.780, p < 0.001, women), while PAF levels were negatively associated with PA only in men (partial rho = -0.627, p = 0.012) and inversely related to DAC. Estimated desaturase 6 was inversely associated with PA (rho = -0.404, p = 0.01, total sample). Moreover, the DAC correlated positively with PA (rho = 0.513, p = 0.03, women). All correlations were adjusted for age, body mass index, and sex (if applicable). Conclusion PA is associated with PAF levels and Lp-PLA2 activity in a gender-dependent fashion, indicating the involvement of PAF in cell membrane impairment. The relationship of PA with DAC suggests a protective effect of antioxidants on cellular health, considering that antioxidants may inhibit PAF generation.
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Affiliation(s)
| | | | | | - Smaragdi Antonopoulou
- Department of Nutrition and Dietetics, School of Health Science and Education. Harokopio University, Athens, Greece
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2
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Dong Y, Yong VW. Oxidized phospholipids as novel mediators of neurodegeneration. Trends Neurosci 2022; 45:419-429. [PMID: 35393134 DOI: 10.1016/j.tins.2022.03.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 02/19/2022] [Accepted: 03/08/2022] [Indexed: 10/18/2022]
Abstract
Neurodegeneration drives the progression of many neurological diseases. Inflammation and oxidative stress occurring in the CNS promote lipid peroxidation, leading to the generation of oxidized phospholipids such as oxidized phosphatidylcholines (OxPCs). OxPCs have been proposed as biomarkers of oxidative stress, where their detection in lesions in multiple sclerosis (MS), frontotemporal lobe dementia, spinal cord injury, and amyotrophic lateral sclerosis (ALS) implies that oxidative insult had occurred. However, recent findings highlight OxPCs as potent neurotoxic species requiring neutralization by microglia. Here, we summarize the science of OxPCs, including lessons from non-CNS diseases. We discuss the potential of OxPCs as common drivers of injury across neurological conditions and encourage investigations of OxPCs as novel neurotoxins.
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Affiliation(s)
- Yifei Dong
- Hotchkiss Brain Institute and the Department of Clinical Neuroscience, University of Calgary, Calgary, Alberta, Canada
| | - V Wee Yong
- Hotchkiss Brain Institute and the Department of Clinical Neuroscience, University of Calgary, Calgary, Alberta, Canada.
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3
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Mitochondrial Lipids: From Membrane Organization to Apoptotic Facilitation. Int J Mol Sci 2022; 23:ijms23073738. [PMID: 35409107 PMCID: PMC8998749 DOI: 10.3390/ijms23073738] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 03/23/2022] [Accepted: 03/25/2022] [Indexed: 02/04/2023] Open
Abstract
Mitochondria are the most complex intracellular organelles, their function combining energy production for survival and apoptosis facilitation for death. Such a multivariate physiology is structurally and functionally reflected upon their membrane configuration and lipid composition. Mitochondrial double membrane lipids, with cardiolipin as the protagonist, show an impressive level of complexity that is mandatory for maintenance of mitochondrial health and protection from apoptosis. Given that lipidomics is an emerging field in cancer research and that mitochondria are the organelles with the most important role in malignant maintenance knowledge of the mitochondrial membrane, lipid physiology in health is mandatory. In this review, we will thus describe the delicate nature of the healthy mitochondrial double membrane and its role in apoptosis. Emphasis will be given on mitochondrial membrane lipids and the changes that they undergo during apoptosis induction and progression.
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4
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Pontes NHL, Reis TDDSD, Vasconcelos CFM, Aragão PDTTDD, Souza RB, Catunda Junior FEA, Aguiar LMV, Cunha RMSD. Impact of eugenol on in vivo model of 6-hydroxydopamine-induced oxidative stress. Free Radic Res 2021; 55:556-568. [PMID: 34424800 DOI: 10.1080/10715762.2021.1971662] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Oxidative stress is involved in many pathological disturbs, such as neurodegenerative disorders. Eugenol (Eug) is a phenolic compound with antioxidant and neuroprotective activities. Then, this study was conducted to investigate the potential neuroprotective effects of Eug on oxidative stress model induced by 6-hydroxydopamine (6-OHDA) in rats. First, the in vivo oxidative stress model was performed by intrastriatal injection (int.) of 6-OHDA (21 µg), followed by the treatment of Eug (0.1, 1, and 10 mg/kg/7 d) per os (p.o.). On the 7 d, behavioral tests were performed. On the 8 d, all the animals were euthanasied and their cerebral areas were excised for neurochemical and transcriptional analyses. The results showed that the treatment with Eug promoted neuroprotective effects on in vivo through reducing of oxidative stress and modulation of genes related to antioxidant activity. Furthermore, animals treated with Eug demonstrated returning of behavioral performance and body weight gain to normal conditions. Thus, this study reports the neuroprotective effects of Eug against oxidative stress induced by 6-OHDA in rats.
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Affiliation(s)
- Nayanne Hardy Lima Pontes
- Biotechnology Core of Sobral, State University of Vale do Acaraú - UVA, Sobral, Brazil.,Faculty of Medicine, Federal University of Ceará - UFC, Sobral, Brazil
| | | | - Carlos Franciney Moreira Vasconcelos
- Biotechnology Core of Sobral, State University of Vale do Acaraú - UVA, Sobral, Brazil.,Faculty of Medicine, Federal University of Ceará - UFC, Sobral, Brazil
| | - Paulo de Tarso Teles Dourado de Aragão
- Biotechnology Core of Sobral, State University of Vale do Acaraú - UVA, Sobral, Brazil.,Faculty of Medicine, Federal University of Ceará - UFC, Sobral, Brazil
| | - Ricardo Basto Souza
- Department of Biochemistry and Molecular Biology, Federal University of Ceará - UFC, Fortaleza, Brazil
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5
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Ademowo OS, Dias IHK, Diaz-Sanchez L, Sanchez-Aranguren L, Stahl W, Griffiths HR. Partial Mitigation of Oxidized Phospholipid-Mediated Mitochondrial Dysfunction in Neuronal Cells by Oxocarotenoids. J Alzheimers Dis 2021; 74:113-126. [PMID: 31985464 DOI: 10.3233/jad-190923] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Mitochondria are important (patho)physiological sources of reactive oxygen species (ROS) that mediate mitochondrial dysfunction and phospholipid oxidation; an increase in mitochondrial content of oxidized phospholipid (OxPL) associates with cell death. Previously we showed that the circulating OxPL 1-palmitoyl-2-(5'-oxo-valeroyl)-sn-glycero-3-phosphocholine (POVPC) increases in patients with Alzheimer's disease (AD), and associates with lower plasma antioxidant oxocarotenoids, zeaxanthin, and lutein. Since oxocarotenoids are metabolized in mitochondria, we propose that during AD, lower concentrations of mitochondrial zeaxanthin and lutein may result in greater phospholipid oxidation and predispose to neurodegeneration. Here, we have investigated whether non-toxic POVPC concentrations impair mitochondrial metabolism in differentiated (d)SH-SY5Y neuronal cells and whether there is any protective role for oxocarotenoids against mitochondrial dysfunction. After 24 hours, glutathione (GSH) concentration was lower in neuronal cells exposed to POVPC (1-20 μM) compared with vehicle control without loss of viability compared to control. However, mitochondrial ROS production (determined by MitoSOX oxidation) was increased by 50% only after 20 μM POVPC. Following delivery of lutein (0.1-1 μM) and zeaxanthin (0.5-5 μM) over 24 hours in vitro, oxocarotenoid recovery from dSH-SY5Y cells was > 50%. Co-incubation with oxocarotenoids prevented loss of GSH after 1 μM but not 20 μM POVPC, whereas the increase in ROS production induced by 20 μM POVPC was prevented by lutein and zeaxanthin. Mitochondrial uncoupling increases and ATP production is inhibited by 20 μM but not 1 μM POVPC; carotenoids protected against uncoupling although did not restore ATP production. In summary, 20 μM POVPC induced loss of GSH and a mitochondrial bioenergetic deficit in neuronal cells that was not mitigated by oxocarotenoids.
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Affiliation(s)
- Opeyemi S Ademowo
- Aston Medical Research Institute, Aston Medical School, Aston University, Birmingham, UK
| | - Irundika H K Dias
- Aston Medical Research Institute, Aston Medical School, Aston University, Birmingham, UK
| | - Lorena Diaz-Sanchez
- Aston Medical Research Institute, Aston Medical School, Aston University, Birmingham, UK
| | | | - Wilhelm Stahl
- Institute of Biochemistry and Molecular Biology 1, Faculty of Medicine, Heinrich-Heine-University Dusseldorf, Dusseldorf, Germany
| | - Helen R Griffiths
- Aston Medical Research Institute, Aston Medical School, Aston University, Birmingham, UK.,Faculty of Health and Medical Sciences, University of Surrey, Stag Hill, Guildford, UK
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6
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Navarro JF, Croteau DL, Jurek A, Andrusivova Z, Yang B, Wang Y, Ogedegbe B, Riaz T, Støen M, Desler C, Rasmussen LJ, Tønjum T, Galas MC, Lundeberg J, Bohr VA. Spatial Transcriptomics Reveals Genes Associated with Dysregulated Mitochondrial Functions and Stress Signaling in Alzheimer Disease. iScience 2020; 23:101556. [PMID: 33083725 PMCID: PMC7522123 DOI: 10.1016/j.isci.2020.101556] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/24/2020] [Accepted: 09/09/2020] [Indexed: 12/15/2022] Open
Abstract
Alzheimer disease (AD) is a devastating neurological disease associated with progressive loss of mental skills and cognitive and physical functions whose etiology is not completely understood. Here, our goal was to simultaneously uncover novel and known molecular targets in the structured layers of the hippocampus and olfactory bulbs that may contribute to early hippocampal synaptic deficits and olfactory dysfunction in AD mice. Spatially resolved transcriptomics was used to identify high-confidence genes that were differentially regulated in AD mice relative to controls. A diverse set of genes that modulate stress responses and transcription were predominant in both hippocampi and olfactory bulbs. Notably, we identify Bok, implicated in mitochondrial physiology and cell death, as a spatially downregulated gene in the hippocampus of mouse and human AD brains. In summary, we provide a rich resource of spatially differentially expressed genes, which may contribute to understanding AD pathology. Spatial transcriptomics identifies differentially expressed genes with spatial patterns Early application of spatial transcriptomics to olfactory bulbs from AD models Bok gene is spatially differentially expressed in AD mouse and patient brains Paip1 and Homer1 genes are regulated in a PolB-dependent manner
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Affiliation(s)
- José Fernández Navarro
- Science for Life Laboratory, Department of Gene Technology, KTH Royal Institute of Technology, 17165 Stockholm, Sweden
| | - Deborah L Croteau
- Laboratory of Molecular Gerontology, National Institute on Aging, Baltimore, MD 21224, USA
| | - Aleksandra Jurek
- Science for Life Laboratory, Department of Gene Technology, KTH Royal Institute of Technology, 17165 Stockholm, Sweden
| | - Zaneta Andrusivova
- Science for Life Laboratory, Department of Gene Technology, KTH Royal Institute of Technology, 17165 Stockholm, Sweden
| | - Beimeng Yang
- Laboratory of Molecular Gerontology, National Institute on Aging, Baltimore, MD 21224, USA
| | - Yue Wang
- Laboratory of Molecular Gerontology, National Institute on Aging, Baltimore, MD 21224, USA
| | - Benjamin Ogedegbe
- Laboratory of Molecular Gerontology, National Institute on Aging, Baltimore, MD 21224, USA
| | - Tahira Riaz
- Unit for Genome Dynamics, Department of Microbiology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway
| | - Mari Støen
- Unit for Genome Dynamics, Department of Microbiology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway
| | - Claus Desler
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Lene Juel Rasmussen
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Tone Tønjum
- Unit for Genome Dynamics, Department of Microbiology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway
| | - Marie-Christine Galas
- University of Lille, Inserm, CHU Lille, UMR-S 1172 - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, 59000 Lille, France
| | - Joakim Lundeberg
- Science for Life Laboratory, Department of Gene Technology, KTH Royal Institute of Technology, 17165 Stockholm, Sweden
| | - Vilhelm A Bohr
- Laboratory of Molecular Gerontology, National Institute on Aging, Baltimore, MD 21224, USA.,Unit for Genome Dynamics, Department of Microbiology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway
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7
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Bagchi AK, Surendran A, Malik A, Jassal DS, Ravandi A, Singal PK. IL-10 attenuates OxPCs-mediated lipid metabolic responses in ischemia reperfusion injury. Sci Rep 2020; 10:12120. [PMID: 32694752 PMCID: PMC7374703 DOI: 10.1038/s41598-020-68995-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 01/03/2020] [Indexed: 12/12/2022] Open
Abstract
Oxidized phospholipids (OxPLs) promote inflammation as well as low density lipoprotein (LDL) uptake in a variety of physiological and pathological states. Given the anti-inflammatory role of the cytokine IL-10, we investigated its modulatory effect on the production of oxidized phosphatidylcholines (OxPCs) as well as lipid metabolic responses in global myocardial ischemia/reperfusion (I/R) injury. Increased OxPCs levels, by 1-Palmitoyl-2-(5-oxovaleryl)-sn-glycero-3-phosphocholine (POVPC), promoted oxidative stress (OS) and cell death. OxPCs-mediated-OS, resulted in oxidized low-density lipoprotein receptor 1 (LOX-1) activation and upregulated the expression of toll-like receptor 2 (TLR2). IL-10-induced increase in proprotein convertase subtilisin/kexin type 9 (PCSK9) negatively regulated LOX-1 as well as TLR2 inflammatory responses. Under stress conditions, phosphorylation of sterol regulatory element binding protein 1c (SREBP 1c) was prevented by IL-10. The latter also prevented the generation of OxPCs and reduced their ratio (OxPCs/PCs) during injury. LOX-1 activation also promoted SREBP1c-mediated TGF-βRII expression which was inhibited by IL-10. Both fragmented and non-fragmented OxPCs were elevated during I/R and this effect was attenuated by IL-10. The largest impact (two–threefold change at log2) was on PAzPC, (1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine)—a fragmented OxPC. Thus it appears that among different OxPCs, IL-10 significantly reduces a single molecule (PAzPC)-mediated lipid metabolic responses in cardiomyocytes thereby mitigating inflammation and cell death.
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Affiliation(s)
- Ashim K Bagchi
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada.,Department of Physiology and Pathophysiology, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada
| | - Arun Surendran
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada.,Department of Physiology and Pathophysiology, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada
| | - Akshi Malik
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada.,Department of Physiology and Pathophysiology, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada
| | - Davinder S Jassal
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada.,Section of Cardiology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
| | - Amir Ravandi
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada.,Section of Cardiology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
| | - Pawan K Singal
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada. .,Department of Physiology and Pathophysiology, St. Boniface Hospital Albrechtsen Research Centre, 351 Tache Ave. Room R3022, Winnipeg, MB, R2H 2A6, Canada.
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8
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Oskolkova OV, Bochkov VN. Gain of function mechanisms triggering biological effects of oxidized phospholipids. CURRENT OPINION IN TOXICOLOGY 2020. [DOI: 10.1016/j.cotox.2020.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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9
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Jawi MM, Frohlich J, Chan SY. Lipoprotein(a) the Insurgent: A New Insight into the Structure, Function, Metabolism, Pathogenicity, and Medications Affecting Lipoprotein(a) Molecule. J Lipids 2020; 2020:3491764. [PMID: 32099678 PMCID: PMC7016456 DOI: 10.1155/2020/3491764] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 08/17/2019] [Indexed: 12/15/2022] Open
Abstract
Lipoprotein(a) [Lp(a)], aka "Lp little a", was discovered in the 1960s in the lab of the Norwegian physician Kåre Berg. Since then, we have greatly improved our knowledge of lipids and cardiovascular disease (CVD). Lp(a) is an enigmatic class of lipoprotein that is exclusively formed in the liver and comprises two main components, a single copy of apolipoprotein (apo) B-100 (apo-B100) tethered to a single copy of a protein denoted as apolipoprotein(a) apo(a). Plasma levels of Lp(a) increase soon after birth to a steady concentration within a few months of life. In adults, Lp(a) levels range widely from <2 to 2500 mg/L. Evidence that elevated Lp(a) levels >300 mg/L contribute to CVD is significant. The improvement of isoform-independent assays, together with the insight from epidemiologic studies, meta-analyses, genome-wide association studies, and Mendelian randomization studies, has established Lp(a) as the single most common independent genetically inherited causal risk factor for CVD. This breakthrough elevated Lp(a) from a biomarker of atherosclerotic risk to a target of therapy. With the emergence of promising second-generation antisense therapy, we hope that we can answer the question of whether Lp(a) is ready for prime-time clinic use. In this review, we present an update on the metabolism, pathophysiology, and current/future medical interventions for high levels of Lp(a).
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Affiliation(s)
- Motasim M. Jawi
- Healthy Heart Program, St. Paul's Hospital, Vancouver V6Z 1Y6, Canada
- Division of Experimental Medicine, Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver V5Z 1M9, Canada
- Department of Clinical PhysiologyCorrection: Department of Physiology, University of Jeddah, P.O. Box: 24, Jeddah 21959, Saudi Arabia
| | - Jiri Frohlich
- Healthy Heart Program, St. Paul's Hospital, Vancouver V6Z 1Y6, Canada
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada
| | - Sammy Y. Chan
- Healthy Heart Program, St. Paul's Hospital, Vancouver V6Z 1Y6, Canada
- Department of Medicine, Division of Cardiology, University of British Columbia, Vancouver V5Z 1M9, Canada
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10
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Stamenkovic A, Pierce GN, Ravandi A. Phospholipid oxidation products in ferroptotic myocardial cell death. Am J Physiol Heart Circ Physiol 2019; 317:H156-H163. [DOI: 10.1152/ajpheart.00076.2019] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Cell death is an important component of the pathophysiology of any disease. Myocardial disease is no exception. Understanding how and why cells die, particularly in the heart where cardiomyocyte regeneration is limited at best, becomes a critical area of study. Ferroptosis is a recently described form of nonapoptotic cell death. It is an iron-mediated form of cell death that occurs because of accumulation of lipid peroxidation products. Reactive oxygen species and iron-mediated phospholipid peroxidation is a hallmark of ferroptosis. To date, ferroptosis has been shown to be involved in cell death associated with Alzheimer’s disease, Huntington’s disease, cancer, Parkinson’s disease, and kidney degradation. Myocardial reperfusion injury is characterized by iron deposition as well as reactive oxygen species production. These conditions, therefore, favor the induction of ferroptosis. Currently there is no available treatment for reperfusion injury, which accounts for up to 50% of the final infarct size. This review will summarize the evidence that ferroptosis can induce cardiomyocyte death following reperfusion injury and the potential for this knowledge to open new therapeutic approaches for myocardial ischemia-reperfusion injury.
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Affiliation(s)
- Aleksandra Stamenkovic
- Institute of Cardiovascular Sciences, Saint Boniface Hospital, and Departments of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Canada
| | - Grant N. Pierce
- Institute of Cardiovascular Sciences, Saint Boniface Hospital, and Departments of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Canada
| | - Amir Ravandi
- Institute of Cardiovascular Sciences, Saint Boniface Hospital, and Departments of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Canada
- Internal Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
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11
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Iuchi K, Ema M, Suzuki M, Yokoyama C, Hisatomi H. Oxidized unsaturated fatty acids induce apoptotic cell death in cultured cells. Mol Med Rep 2019; 19:2767-2773. [PMID: 30720142 PMCID: PMC6423586 DOI: 10.3892/mmr.2019.9940] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 01/28/2019] [Indexed: 12/20/2022] Open
Abstract
Polyunsaturated fatty acids are oxidized by non-enzymatic or enzymatic reactions. The oxidized products are multifunctional. In this study, we investigated how oxidized fatty acids inhibit cell proliferation in cultured cells. We used polyunsaturated and saturated fatty acids, docosahexaenoic acid (DHA; 22:6), eicosapentaenoic acid (EPA; 20:5), linoleic acid (LA; 18:2), and palmitic acid (16:0). Oxidized fatty acids were produced by autoxidation of fatty acids for 2 days in the presence of a gas mixture (20% O2 and 80% N2). We found that oxidized polyunsaturated fatty acids (OxDHA, OxEPA and OxLA) inhibited cell proliferation much more effectively compared with un-oxidized fatty acids (DHA, EPA and LA, respectively) in THP-1 (a human monocytic leukemia cell line) and DLD-1 (a human colorectal cancer cell line) cells. In particular, OxDHA markedly inhibited cell proliferation. DHA has the largest number of double bonds and is most susceptible to oxidation among the fatty acids. OxDHA has the largest number of highly active oxidized products. Therefore, the oxidative levels of fatty acids are associated with the anti-proliferative activity. Moreover, caspase-3/7 was activated in the cells treated with OxDHA, but not in those treated with DHA. A pan-caspase inhibitor (zVAD-fmk) reduced the cell death induced by OxDHA. These results indicated that oxidized products from polyunsaturated fatty acids induced apoptosis in cultured cells. Collectively, the switch between cell survival and cell death may be regulated by the activity and/or number of oxidized products from polyunsaturated fatty acids.
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Affiliation(s)
- Katsuya Iuchi
- Department of Materials and Life Science, Faculty of Science and Technology, Seikei University, Tokyo 180‑8633, Japan
| | - Mika Ema
- Department of Materials and Life Science, Faculty of Science and Technology, Seikei University, Tokyo 180‑8633, Japan
| | - Moe Suzuki
- Department of Materials and Life Science, Faculty of Science and Technology, Seikei University, Tokyo 180‑8633, Japan
| | - Chikako Yokoyama
- Department of Biochemical Engineering, Graduate School of Science and Engineering, Yamagata University, Yonezawa, Yamagata 992‑8510, Japan
| | - Hisashi Hisatomi
- Department of Materials and Life Science, Faculty of Science and Technology, Seikei University, Tokyo 180‑8633, Japan
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12
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Yeang C, Hasanally D, Que X, Hung MY, Stamenkovic A, Chan D, Chaudhary R, Margulets V, Edel AL, Hoshijima M, Gu Y, Bradford W, Dalton N, Miu P, Cheung DY, Jassal DS, Pierce GN, Peterson KL, Kirshenbaum LA, Witztum JL, Tsimikas S, Ravandi A. Reduction of myocardial ischaemia-reperfusion injury by inactivating oxidized phospholipids. Cardiovasc Res 2019; 115:179-189. [PMID: 29850765 PMCID: PMC6302283 DOI: 10.1093/cvr/cvy136] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 04/18/2018] [Accepted: 05/22/2018] [Indexed: 02/06/2023] Open
Abstract
Aims Myocardial ischaemia followed by reperfusion (IR) causes an oxidative burst resulting in cellular dysfunction. Little is known about the impact of oxidative stress on cardiomyocyte lipids and their role in cardiac cell death. Our goal was to identify oxidized phosphatidylcholine-containing phospholipids (OxPL) generated during IR, and to determine their impact on cell viability and myocardial infarct size. Methods and results OxPL were quantitated in isolated rat cardiomyocytes using mass spectrophotometry following 24 h of IR. Cardiomyocyte cell death was quantitated following exogenously added OxPL and in the absence or presence of E06, a 'natural' murine monoclonal antibody that binds to the PC headgroup of OxPL. The impact of OxPL on mitochondria in cardiomyocytes was also determined using cell fractionation and Bnip expression. Transgenic Ldlr-/- mice, overexpressing a single-chain variable fragment of E06 (Ldlr-/--E06-scFv-Tg) were used to assess the effect of inactivating endogenously generated OxPL in vivo on myocardial infarct size. Following IR in vitro, isolated rat cardiomyocytes showed a significant increase in the specific OxPLs PONPC, POVPC, PAzPC, and PGPC (P < 0.05 to P < 0.001 for all). Exogenously added OxPLs resulted in significant death of rat cardiomyocytes, an effect inhibited by E06 (percent cell death with added POVPC was 22.6 ± 4.14% and with PONPC was 25.3 ± 3.4% compared to 8.0 ± 1.6% and 6.4 ± 1.0%, respectively, with the addition of E06, P < 0.05 for both). IR increased mitochondrial content of OxPL in rat cardiomyocytes and also increased expression of Bcl-2 death protein 3 (Bnip3), which was inhibited in presence of E06. Notably cardiomyocytes with Bnip3 knock-down were protected against cytotoxic effects of OxPL. In mice exposed to myocardial IR in vivo, compared to Ldlr-/- mice, Ldlr-/--E06-scFv-Tg mice had significantly smaller myocardial infarct size normalized to area at risk (72.4 ± 21.9% vs. 47.7 ± 17.6%, P = 0.023). Conclusions OxPL are generated within cardiomyocytes during IR and have detrimental effects on cardiomyocyte viability. Inactivation of OxPL in vivo results in a reduction of infarct size.
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MESH Headings
- Animals
- Cell Death
- Cells, Cultured
- Disease Models, Animal
- Male
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Mice, Inbred C57BL
- Mice, Knockout
- Mitochondria, Heart/metabolism
- Mitochondria, Heart/pathology
- Mitochondrial Proteins/genetics
- Mitochondrial Proteins/metabolism
- Myocardial Infarction/genetics
- Myocardial Infarction/metabolism
- Myocardial Infarction/pathology
- Myocardial Infarction/prevention & control
- Myocardial Reperfusion Injury/genetics
- Myocardial Reperfusion Injury/metabolism
- Myocardial Reperfusion Injury/pathology
- Myocardial Reperfusion Injury/prevention & control
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/pathology
- Oxidation-Reduction
- Oxidative Stress/drug effects
- Phospholipids/metabolism
- Rats, Sprague-Dawley
- Receptors, LDL/genetics
- Receptors, LDL/metabolism
- Signal Transduction
- Single-Chain Antibodies/genetics
- Single-Chain Antibodies/metabolism
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Affiliation(s)
- Calvin Yeang
- Division of Cardiovascular Diseases, Sulpizio Cardiovascular Center, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Devin Hasanally
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Xuchu Que
- Division of Endocrinology and Metabolism, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Ming-Yow Hung
- Division of Cardiology, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei City, Taiwan
| | - Aleksandra Stamenkovic
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - David Chan
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Rakesh Chaudhary
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Victoria Margulets
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Andrea L Edel
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Masahiko Hoshijima
- Division of Cardiovascular Diseases, Sulpizio Cardiovascular Center, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Yusu Gu
- Division of Cardiovascular Diseases, Sulpizio Cardiovascular Center, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - William Bradford
- Division of Cardiovascular Diseases, Sulpizio Cardiovascular Center, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Nancy Dalton
- Division of Cardiovascular Diseases, Sulpizio Cardiovascular Center, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Phuong Miu
- Division of Cardiovascular Diseases, Sulpizio Cardiovascular Center, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - David Yc Cheung
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Davinder S Jassal
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
- Department of Physiology and Pathophysiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Grant N Pierce
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
- Department of Physiology and Pathophysiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Kirk L Peterson
- Division of Cardiovascular Diseases, Sulpizio Cardiovascular Center, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Lorrie A Kirshenbaum
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Joseph L Witztum
- Division of Endocrinology and Metabolism, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Sotirios Tsimikas
- Division of Cardiovascular Diseases, Sulpizio Cardiovascular Center, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Amir Ravandi
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
- Department of Physiology and Pathophysiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
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13
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Dingeldein A, Sparrman T, Gröbner G. Oxidatively stressed mitochondria-mimicking membranes: A molecular insight into their organization during apoptosis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:2644-2654. [DOI: 10.1016/j.bbamem.2018.10.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 09/24/2018] [Accepted: 10/03/2018] [Indexed: 12/14/2022]
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14
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Tselepis AD. Oxidized phospholipids and lipoprotein-associated phospholipase A 2 as important determinants of Lp(a) functionality and pathophysiological role. J Biomed Res 2018; 31. [PMID: 27346583 PMCID: PMC5956253 DOI: 10.7555/jbr.31.20160009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 01/29/2016] [Accepted: 02/12/2016] [Indexed: 12/23/2022] Open
Abstract
Lipoprotein(a) [Lp(a)] is composed of a low density lipoprotein (LDL)-like particle to which apolipoprotein (a) [apo(a)] is linked by a single disulfide bridge. Lp(a) is considered a causal risk factor for ischemic cardiovascular disease (CVD) and calcific aortic valve stenosis (CAVS). The evidence for a causal role of Lp(a) in CVD and CAVS is based on data from large epidemiological databases, mendelian randomization studies, and genome-wide association studies. Despite the well-established role of Lp(a) as a causal risk factor for CVD and CAVS, the underlying mechanisms are not well understood. A key role in the Lp(a) functionality may be played by its oxidized phospholipids (OxPL) content. Importantly, most of circulating OxPL are associated with Lp(a); however, the underlying mechanisms leading to this preferential sequestration of OxPL on Lp(a) over the other lipoproteins, are mostly unknown. Several studies support the hypothesis that the risk of Lp(a) is primarily driven by its OxPL content. An important role in Lp(a) functionality may be played by the lipoprotein-associated phospholipase A2 (Lp-PLA2), an enzyme that catalyzes the degradation of OxPL and is bound to plasma lipoproteins including Lp(a). The present review article discusses new data on the pathophysiological role of Lp(a) and particularly focuses on the functional role of OxPL and Lp-PLA2 associated with Lp(a).
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Affiliation(s)
- Alexandros D Tselepis
- Atherothrombosis Research Centre / Laboratory of Biochemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece.
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15
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Abstract
This review based on translational research predicts that the transcription factor p53 is the key effector of all anti-acne therapies. All-trans retinoic acid (ATRA) and isotretinoin (13-cis retinoic acid) enhance p53 expression. Tetracyclines and macrolides via inhibiting p450 enzymes attenuate ATRA degradation, thereby increase p53. Benzoyl peroxide and hydrogen peroxide elicit oxidative stress, which upregulates p53. Azelaic acid leads to mitochondrial damage associated with increased release of reactive oxygen species inducing p53. p53 inhibits the expression of androgen receptor and IGF-1 receptor, and induces the expression of IGF binding protein 3. p53 induces FoxO1, FoxO3, p21 and sestrin 1, sestrin 2, and tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), the key inducer of isotretinoin-mediated sebocyte apoptosis explaining isotretinoin's sebum-suppressive effect. Anti-androgens attenuate the expression of miRNA-125b, a key negative regulator of p53. It can thus be concluded that all anti-acne therapies have a common mode of action, i.e., upregulation of the guardian of the genome p53. Immortalized p53-inactivated sebocyte cultures are unfortunate models for studying acne pathogenesis and treatment.
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Affiliation(s)
- Bodo C Melnik
- Department of Dermatology, Environmental Medicine and Health Theory, University of Osnabrück, Am Finkenhügel 7a, 49076, Osnabrück, Germany.
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16
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Abe A, Hiraoka M, Ohguro H, Tesmer JJ, Shayman JA. Preferential hydrolysis of truncated oxidized glycerophospholipids by lysosomal phospholipase A2. J Lipid Res 2016; 58:339-349. [PMID: 27993948 DOI: 10.1194/jlr.m070730] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 12/08/2016] [Indexed: 01/18/2023] Open
Abstract
Truncated oxidized glycerophospholipids (ox-PLs) are bioactive lipids resulting from oxidative stress. The catabolic pathways for truncated ox-PLs are not fully understood. Lysosomal phospholipase A2 (LPLA2) with phospholipase A and transacylase activities is a key enzyme in phospholipid homeostasis. The present study assessed whether LPLA2 could hydrolyze truncated ox-PLs. Incubation of LPLA2 with liposomes consisting of 1,2-O-octadecenyl-sn-glycero-3-phosphocholine (DODPC)/1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) or truncated oxidized phosphatidylcholine (ox-PC)/N-acetylsphingosine (NAS) under acidic conditions resulted in the preferential deacylation at the sn-1 position of the truncated ox-PCs. Additionally, the release of free fatty acid from the truncated ox-PCs preferentially occurred compared with the NAS-acylation. Incubation of LPLA2 with the liposomes consisting of DODPC/DOPC/truncated ox-PC/NAS resulted in the same preferential fatty acid release from the truncated ox-PC. The cationic amphiphilic drug, amiodarone, did not inhibit such fatty acid release, indicating that truncated ox-PCs partition from the lipid membrane into the aqueous phase and react with free LPLA2. Consistent with this mechanism, the hydrolysis of some truncated ox-PCs, but not DOPC, by LPLA2 was detected at neutral pH. Additionally, LPLA2-overexpressed Chinese hamster ovary cells efficiently catabolized truncated ox-PC and were protected from growth inhibition. These findings support the existence of a novel catabolic pathway for truncated ox-PLs via LPLA2.
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Affiliation(s)
- Akira Abe
- Department of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo, Japan
| | - Miki Hiraoka
- Department of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo, Japan
| | - Hiroshi Ohguro
- Department of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo, Japan
| | - John J Tesmer
- Life Sciences Institute and Departments of Pharmacology, Biological Chemistry, University of Michigan, Ann Arbor, MI
| | - James A Shayman
- Internal Medicine, University of Michigan Medical School, University of Michigan, Ann Arbor, MI
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17
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Identification of Oxidized Phosphatidylinositols Present in OxLDL and Human Atherosclerotic Plaque. Lipids 2016; 52:11-26. [PMID: 27914034 DOI: 10.1007/s11745-016-4217-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/19/2016] [Indexed: 01/11/2023]
Abstract
Oxidized low-density lipoprotein (OxLDL) plays an important role in initiation and progression of atherosclerosis. Proatherogenic effects of OxLDL have been attributed to bioactive phospholipids generated during LDL oxidation. It is unknown what effect oxidation has on the phosphatidylinositol (PtdIns) molecules in LDL, even though PtdIns is 6% of the total LDL phospholipid pool. We sought to identify and quantitate oxidized phosphatidylinositol (OxPtdIns) species in OxLDL and human atherosclerotic plaque. Bovine liver PtdIns was subjected to non-enzymatic and lipoxygenase-catalyzed oxidation. Reversed-phase liquid chromatography with negative ESI-MS identified and confirmed compounds by fragmentation pattern analysis from which an OxPtdIns library was generated. Twenty-three OxPtdIns molecules were identified in copper-oxidized human LDL at 0, 6, 12, 24, 30, and 48 h, and in human atherosclerotic plaque. In OxLDL, OxPtdIns species containing aldehydes and carboxylates comprised 17.3 ± 0.1 and 0.9 ± 0.2%, respectively, of total OxPtdIns in OxLDL at 48 h. Hydroperoxides and isoprostanes at 24 h (68.5 ± 0.2 and 22.8 ± 0.2%) were significantly greater than 12 h (P < 0.01) without additional changes thereafter. Hydroxides decreased with increased oxidation achieving a minimum at 24 h (5.2 ± 0.3%). Human atherosclerotic plaques contained OxPtdIns species including aldehydes, carboxylates, hydroxides, hydroperoxides and isoprostanes, comprising 18.6 ± 4.7, 1.5 ± 0.7, 16.5 ± 7.4, 33.3 ± 1.1 and 30.2 ± 3.3% of total OxPtdIns compounds. This is the first identification of OxPtdIns molecules in human OxLDL and atherosclerotic plaque. With these novel molecules identified we can now investigate their potential role in atherosclerosis.
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18
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Lidman M, Pokorná Š, Dingeldein APG, Sparrman T, Wallgren M, Šachl R, Hof M, Gröbner G. The oxidized phospholipid PazePC promotes permeabilization of mitochondrial membranes by Bax. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:1288-97. [PMID: 26947183 DOI: 10.1016/j.bbamem.2016.03.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 02/24/2016] [Accepted: 03/02/2016] [Indexed: 12/25/2022]
Abstract
Mitochondria play a crucial role in programmed cell death via the intrinsic apoptotic pathway, which is tightly regulated by the B-cell CLL/lymphoma-2 (Bcl-2) protein family. Intracellular oxidative stress causes the translocation of Bax, a pro-apoptotic family member, to the mitochondrial outer membrane (MOM) where it induces membrane permeabilization. Oxidized phospholipids (OxPls) generated in the MOM during oxidative stress directly affect the onset and progression of mitochondria-mediated apoptosis. Here we use MOM-mimicking lipid vesicles doped with varying concentrations of 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazePC), an OxPl species known to significantly enhance Bax-membrane association, to investigate three key aspects of Bax's action at the MOM: 1) induction of Bax pores in membranes without additional mediator proteins, 2) existence of a threshold OxPl concentration required for Bax-membrane action and 3) mechanism by which PazePC disturbs membrane organization to facilitate Bax penetration. Fluorescence leakage studies revealed that Bax-induced leakage, especially its rate, increased with the vesicles' PazePC content without any detectable threshold neither for OxPl nor Bax. Moreover, the leakage rate correlated with the Bax to lipid ratio and the PazePC content. Solid state NMR studies and calorimetric experiments on the lipid vesicles confirmed that OxPl incorporation disrupted the membrane's organization, enabling Bax to penetrate into the membrane. In addition, 15N cross polarization (CP) and insensitive nuclei enhanced by polarization transfer (INEPT) MAS NMR experiments using uniformly (15)N-labeled Bax revealed dynamically restricted helical segments of Bax embedded in the membrane, while highly flexible protein segments were located outside or at the membrane surface.
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Affiliation(s)
- Martin Lidman
- Department of Chemistry, University of Umeå, SE-901 87 Umeå, Sweden
| | - Šárka Pokorná
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejškova 3, 182 23 Prague 8, Czech Republic; Department of Biochemistry, Charles University, Hlavova 8, 128 40 Prague 2, Czech Republic
| | | | - Tobias Sparrman
- Department of Chemistry, University of Umeå, SE-901 87 Umeå, Sweden
| | - Marcus Wallgren
- Department of Medical Chemistry and Biophysics, University of Umeå, SE-901 87 Umeå, Sweden
| | - Radek Šachl
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejškova 3, 182 23 Prague 8, Czech Republic
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v. v. i., Dolejškova 3, 182 23 Prague 8, Czech Republic
| | - Gerhard Gröbner
- Department of Chemistry, University of Umeå, SE-901 87 Umeå, Sweden.
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19
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Latchoumycandane C, Hanouneh M, Nagy LE, McIntyre TM. Inflammatory PAF Receptor Signaling Initiates Hedgehog Signaling and Kidney Fibrogenesis During Ethanol Consumption. PLoS One 2015; 10:e0145691. [PMID: 26720402 PMCID: PMC4697844 DOI: 10.1371/journal.pone.0145691] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 12/06/2015] [Indexed: 12/20/2022] Open
Abstract
Acute inflammation either resolves or proceeds to fibrotic repair that replaces functional tissue. Pro-fibrotic hedgehog signaling and induction of its Gli transcription factor in pericytes induces fibrosis in kidney, but molecular instructions connecting inflammation to fibrosis are opaque. We show acute kidney inflammation resulting from chronic ingestion of the common xenobiotic ethanol initiates Gli1 transcription and hedgehog synthesis in kidney pericytes, and promotes renal fibrosis. Ethanol ingestion stimulated transcription of TGF-ß, collagens I and IV, and alpha-smooth muscle actin with accumulation of these proteins. This was accompanied by deposition of extracellular fibrils. Ethanol catabolism by CYP2E1 in kidney generates local reactive oxygen species that oxidize cellular phospholipids to phospholipid products that activate the Platelet-activating Factor receptor (PTAFR) for inflammatory phospholipids. Genetically deleting this ptafr locus abolished accumulation of mRNA for TGF-ß, collagen IV, and α-smooth muscle actin. Loss of PTAFR also abolished ethanol-stimulated Sonic (Shh) and Indian hedgehog (Ihh) expression, and abolished transcription and accumulation of Gli1. Shh induced in pericytes and Ihh in tubules escaped to urine of ethanol-fed mice. Neutrophil myeloperoxidase (MPO) is required for ethanol-induced kidney inflammation, and Shh was not present in kidney or urine of mpo-/- mice. Shh also was present in urine of patients with acute kidney injury, but not in normal individuals or those with fibrotic liver cirrhosis We conclude neither endogenous PTAFR signaling nor CYP2E1-generated radicals alone are sufficient to initiate hedgehog signaling, but instead PTAFR-dependent neutrophil infiltration with myeloperoxidase activation is necessary to initiate ethanol-induced fibrosis in kidney. We also show fibrogenic mediators escape to urine, defining a new class of urinary mechanistic biomarkers of fibrogenesis for an organ not commonly biopsied.
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Affiliation(s)
- Calivarathan Latchoumycandane
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Mohamad Hanouneh
- Department of Internal Medicine, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Laura E Nagy
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Thomas M McIntyre
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
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20
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Abstract
This chapter is focused on the role of the plasma form of platelet-activating factor-acetylhydrolase (PAF-AH), heretofore referred to as PAF-AH, in tumorigenic responses. Biochemical and other properties of this enzyme were discussed in detail in chapter "Plasma PAF-AH (PLA2G7): Biochemical Properties, Association with LDLs and HDLs, and Regulation of Expression" by Stafforini and in other chapters. Although phospholipases tend not to be drivers of tumorigenesis themselves, these enzymes and the lipid mediators whose levels they regulate interact with a variety of oncogenes and tumor suppressors [1]. Like other phospholipases, the functions of PAF-AH in cancer likely are related to its ability to regulate the levels of lipid mediators that participate in cellular processes related to initial tumorigenic events (e.g., proliferation, growth, inflammation) and/or spreading of the disease (e.g., matrix metalloproteinase secretion, actin cytoskeleton reorganization, migration, and angiogenesis) [1]. The importance of substrates and products of PAF-AH on key cellular functions has been evaluated in cell-based analyses which revealed that these metabolites can have pro- and antitumorigenic functions. Studies in genetically engineered mice lacking PAF-AH expression and genetic manipulation of PAF-AH levels in cancer cells demonstrated diverse functions of the protein in models of melanoma, prostate cancer, colon cancer, and others. The following sections highlight lessons learned from studies in cell lines and in mouse models regarding the diversity of functions of PAF-AH in cancer, and the potential of PAFAH transcripts, protein, and/or activity levels to become cancer biomarkers and therapeutic targets.
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Affiliation(s)
- Diana M Stafforini
- Huntsman Cancer Institute and Division of Cardiovascular Medicine, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.
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21
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Goudarzi M, Weber WM, Chung J, Doyle-Eisele M, Melo DR, Mak TD, Strawn SJ, Brenner DJ, Guilmette R, Fornace AJ. Serum Dyslipidemia Is Induced by Internal Exposure to Strontium-90 in Mice, Lipidomic Profiling Using a Data-Independent Liquid Chromatography-Mass Spectrometry Approach. J Proteome Res 2015; 14:4039-49. [PMID: 26262552 DOI: 10.1021/acs.jproteome.5b00576] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Despite considerable research into the environmental risks and biological effects of exposure to external beam γ rays, incorporation of radionuclides has largely been understudied. This dosimetry and exposure risk assessment is challenging for first responders in the field during a nuclear or radiological event. Therefore, we have developed a workflow for assessing injury responses in easily obtainable biofluids, such as urine and serum, as the result of exposure to internal emitters cesium-137 ((137)Cs) and strontium-90 ((90)Sr) in mice. Here we report on the results of the untargeted lipidomic profiling of serum from mice exposed to (90)Sr. We also compared these results to those from previously published (137)Cs exposure to determine any differences in cellular responses based on exposure type. The results of this study conclude that there is a gross increase in the serum abundance of triacylglycerides and cholesterol esters, while phostaphatidylcholines and lysophosphatidylcholines displayed decreases in their serum levels postexposure at study days 4, 7, 9, 25, and 30, with corresponding average cumulative skeleton doses ranging from 1.2 ± 0.1 to 5.2 ± 0.73 Gy. The results show significant perturbations in serum lipidome as early as 2 days postexposure persisting until the end of the study (day 30).
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Affiliation(s)
- Maryam Goudarzi
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University , 3970 Reservoir Rd. NW, Washington, D.C. 20057, United States
| | - Waylon M Weber
- Lovelace Respiratory Research Institute, 2425 Ridgecrest Dr. SE, Albuquerque, New Mexico 87108, United States
| | - Juijung Chung
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University , 3970 Reservoir Rd. NW, Washington, D.C. 20057, United States
| | - Melanie Doyle-Eisele
- Lovelace Respiratory Research Institute, 2425 Ridgecrest Dr. SE, Albuquerque, New Mexico 87108, United States
| | - Dunstana R Melo
- Lovelace Respiratory Research Institute, 2425 Ridgecrest Dr. SE, Albuquerque, New Mexico 87108, United States
| | - Tytus D Mak
- Mass Spectrometry Data Center, National Institute of Standards and Technology , 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| | - Steven J Strawn
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University , 3970 Reservoir Rd. NW, Washington, D.C. 20057, United States
| | - David J Brenner
- Center for Radiological Research, Columbia University , 630 West 168th Street, VC11-240, New York, New York 10032, United States
| | - Raymond Guilmette
- Lovelace Respiratory Research Institute, 2425 Ridgecrest Dr. SE, Albuquerque, New Mexico 87108, United States
| | - Albert J Fornace
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University , 3970 Reservoir Rd. NW, Washington, D.C. 20057, United States.,Lombardi Comprehensive Cancer Center, Georgetown University , Washington, D.C. 20057, United States
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22
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Makky A, Tanaka M. Impact of lipid oxidization on biophysical properties of model cell membranes. J Phys Chem B 2015; 119:5857-63. [PMID: 25870900 DOI: 10.1021/jp512339m] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The oxidization of glycerophospholipids in cell membranes due to aging and environmental stresses may cause a variety of pathological and physiological consequences. A variety of oxidized phospholipid products (OxPl) are produced by the chemical oxidization of unsaturated hydrocarbon chains, which would significantly change the physicochemical properties of cell membranes. In this work, we constructed cell membrane models in the absence and presence of two stable oxidized lipid products and investigated their impact on physical properties of supported membranes using quartz crystal microbalance with dissipation (QCM-D) and high-energy X-ray reflectivity (XRR). Our experimental findings suggest that the lipid oxidization up to 20 mol % leads to the rupture of vesicles right after the adsorption. Our XRR analysis unravels the membrane thinning and the decrease in the lateral ordering of lipids, which can be explained by the decrease in the lateral packing of hydrocarbon chains. Further studies on mechanics of membranes incorporating oxidized lipids can be attributed to the decrease in the bending rigidity and the increase in the permeability.
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Affiliation(s)
- Ali Makky
- †Physical Chemistry of Biosystems, Institute of Physical Chemistry, Heidelberg University, D69120 Heidelberg, Germany
| | - Motomu Tanaka
- †Physical Chemistry of Biosystems, Institute of Physical Chemistry, Heidelberg University, D69120 Heidelberg, Germany.,‡Institute for Toxicology and Genetics, Karlsruhe Institute for Technology, D76021 Karlsruhe, Germany.,§Institute for Integrated Cell-Material Sciences (WPI iCeMS), Kyoto University, 606-8501 Kyoto, Japan
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23
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Karasawa K. Naturally Occurring Missense Mutation in Plasma PAF-AH Among the Japanese Population. Enzymes 2015; 38:117-43. [PMID: 26612650 DOI: 10.1016/bs.enz.2015.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A single nucleotide polymorphism in the plasma PAF-AH enzyme, i.e., G994T, which causes the substitution of Val at amino acid 279 with Phe (V279F), has been found in the Japanese population. This enzyme preferentially degrades oxidatively modulated or truncated phospholipids; therefore, it has been suggested that this enzyme may prevent the accumulation of proinflammatory and proatherogenic oxidized phospholipids. This hypothesis is supported by the higher prevalence of the V279F mutation in patients with asthmatic and atherosclerotic diseases, as compared with healthy controls. This mutation is rare in the Caucasian population. The plasma PAF-AH mass and enzyme activity are distributed over a wide range in the plasma and they are positively correlated with low-density lipoprotein (LDL) cholesterol. However, several clinical studies in the Caucasian population have suggested that this enzyme has the opposite role. This enzyme plays an active role in the development and progression of atherosclerosis via proinflammatory and proatherogenic lysophosphatidylcholine and oxidized fatty acids produced through the oxidation of LDL by this enzyme. Thus, plasma PAF-AH is a unique enzyme with dual roles in human inflammatory diseases. In this chapter, on the basis of recent findings we describe the association between a naturally occurring missense mutation in plasma PAF-AH and human diseases especially including atherosclerosis and asthma.
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Affiliation(s)
- Ken Karasawa
- Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo, Japan.
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24
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Burns TA, Watts MR, Weber PS, McCutcheon LJ, Geor RJ, Belknap JK. Effect of dietary nonstructural carbohydrate content on activation of 5'-adenosine monophosphate-activated protein kinase in liver, skeletal muscle, and digital laminae of lean and obese ponies. J Vet Intern Med 2014; 28:1280-8. [PMID: 24750267 PMCID: PMC4857936 DOI: 10.1111/jvim.12356] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 12/13/2013] [Accepted: 03/05/2014] [Indexed: 01/16/2023] Open
Abstract
Background In EMS‐associated laminitis, laminar failure may occur in response to energy failure related to insulin resistance (IR) or to the effect of hyperinsulinemia on laminar tissue. 5′‐Adenosine‐monophosphate‐activated protein kinase (AMPK) is a marker of tissue energy deprivation, which may occur in IR. Hypothesis/Objectives To characterize tissue AMPK regulation in ponies subjected to a dietary carbohydrate (CHO) challenge. Animals Twenty‐two mixed‐breed ponies. Methods Immunohistochemistry and immunoblotting for total AMPK and phospho(P)‐AMPK and RT‐qPCR for AMPK‐responsive genes were performed on laminar, liver, and skeletal muscle samples collected after a 7‐day feeding protocol in which ponies stratified on body condition score (BCS; obese or lean) were fed either a low‐CHO diet (ESC + starch, approximately 7% DM; n = 5 obese, 5 lean) or a high‐CHO diet (ESC + starch, approximately 42% DM; n = 6 obese, 6 lean). Results 5′‐Adenosine‐monophosphate‐activated protein kinase was immunolocalized to laminar keratinocytes, dermal constituents, and hepatocytes. A high‐CHO diet resulted in significantly decreased laminar [P‐AMPK] in lean ponies (P = .03), but no changes in skeletal muscle (lean, P = .33; obese, P = .43) or liver (lean, P = .84; obese, P = .13) [P‐AMPK]. An inverse correlation existed between [blood glucose] and laminar [P‐AMPK] in obese ponies on a high‐CHO diet. Conclusions and Clinical Importance Laminar tissue exhibited a normal response to a high‐CHO diet (decreased [P‐AMPK]), whereas this response was not observed in liver and skeletal muscle in both lean (skeletal muscle, P = .33; liver, P = .84) and obese (skeletal muscle, P = .43; liver, P = .13) ponies.
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Affiliation(s)
- T A Burns
- The Ohio State University College of Veterinary Medicine, Columbus, OH
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Maeda T, Takeuchi K, Xiaoling P, P Zankov D, Takashima N, Fujiyoshi A, Kadowaki T, Miura K, Ueshima H, Ogita H. Lipoprotein-associated phospholipase A2 regulates macrophage apoptosis via the Akt and caspase-7 pathways. J Atheroscler Thromb 2014; 21:839-53. [PMID: 24717759 DOI: 10.5551/jat.21386] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
AIM Mutations in lipoprotein-associated phospholipase A2 (Lp-PLA2) are related to atherosclerosis. However, the molecular effects of Lp-PLA2 on atherosclerosis have not been fully investigated. Therefore, this study attempted to elucidate this issue. METHODS Monocytes were isolated from randomly selected healthy male volunteers according to each Lp-PLA2 genotype (wild-type Lp-PLA2 [Lp-PLA2 (V/V)], the heterozygous V279F mutation [LpPLA2 (V/F)] and the homozygous V279F mutation [Lp-PLA2 (F/F)]) and differentiated into macrophages. The level of apoptosis in the macrophages following incubation without serum was measured using the annexin V/propidium iodide double staining method, and the underlying mechanisms were further examined using a culture cell line. RESULTS The average plasma Lp-PLA2 concentration [Lp-PLA2 (V/V): 129.4 ng/mL, Lp-PLA2 (V/F): 70.7 ng/mL, Lp-PLA2 (F/F): 0.4 ng/mL] and activity [Lp-PLA2 (V/V): 164.3 nmol/min/mL, LpPLA2 (V/F): 100.9 nmol/min/mL, Lp-PLA2 (F/F): 11.6 nmol/min/mL] were significantly different between each genotype, although the basic clinical characteristics were similar. The percentage of apoptotic cells was significantly higher among the Lp-PLA2 (F/F) macrophages compared with that observed in the Lp-PLA2 (V/V) macrophages. This induction of apoptosis was independent of the actions of acetylated low-density lipoproteins. In addition, the transfection of the expression plasmid of V279F mutant Lp-PLA2 into Cos-7 cells or monocyte/macrophage-like U937 cells promoted apoptosis. The knockdown of Lp-PLA2 also increased the number of apoptotic cells. Among the cells expressing mutant Lp-PLA2, the caspase-7 activity was increased, while the activated Akt level was decreased. CONCLUSIONS The V279F mutation of Lp-PLA2 positively regulates the induction of apoptosis in macrophages and Cos-7 cells. An increase in the caspase-7 activity and a reduction in the activated Akt level are likely to be involved in this phenomenon.
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Affiliation(s)
- Toshinaga Maeda
- Division of Molecular Medical Biochemistry, Department of Biochemistry and Molecular Biology, Shiga University of Medical Science
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Davies SS, Guo L. Lipid peroxidation generates biologically active phospholipids including oxidatively N-modified phospholipids. Chem Phys Lipids 2014; 181:1-33. [PMID: 24704586 DOI: 10.1016/j.chemphyslip.2014.03.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Revised: 02/28/2014] [Accepted: 03/18/2014] [Indexed: 12/25/2022]
Abstract
Peroxidation of membranes and lipoproteins converts "inert" phospholipids into a plethora of oxidatively modified phospholipids (oxPL) that can act as signaling molecules. In this review, we will discuss four major classes of oxPL: mildly oxygenated phospholipids, phospholipids with oxidatively truncated acyl chains, phospholipids with cyclized acyl chains, and phospholipids that have been oxidatively N-modified on their headgroups by reactive lipid species. For each class of oxPL we will review the chemical mechanisms of their formation, the evidence for their formation in biological samples, the biological activities and signaling pathways associated with them, and the catabolic pathways for their elimination. We will end by briefly highlighting some of the critical questions that remain about the role of oxPL in physiology and disease.
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Affiliation(s)
- Sean S Davies
- Division of Clinical Pharmacology, Department of Pharmacology, Vanderbilt University, United States.
| | - Lilu Guo
- Division of Clinical Pharmacology, Department of Pharmacology, Vanderbilt University, United States
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Bocchini N, Giantin M, Crivellente F, Ferraresso S, Faustinelli I, Dacasto M, Cristofori P. Molecular biomarkers of phospholipidosis in rat blood and heart after amiodarone treatment. J Appl Toxicol 2014; 35:90-103. [DOI: 10.1002/jat.2992] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Nicola Bocchini
- Dipartimento di Biomedicina Comparata e Alimentazione; Università di Padova; viale dell'Università 16 I-35020 Legnaro (Padova) Italy
- Scuola di Dottorato in Scienze Veterinarie, indirizzo di Sanità pubblica e Patologia comparata; viale dell'Università 16 I-35020 Legnaro (Padova) Italy
| | - Mery Giantin
- Dipartimento di Biomedicina Comparata e Alimentazione; Università di Padova; viale dell'Università 16 I-35020 Legnaro (Padova) Italy
| | | | - Serena Ferraresso
- Dipartimento di Biomedicina Comparata e Alimentazione; Università di Padova; viale dell'Università 16 I-35020 Legnaro (Padova) Italy
| | - Ivo Faustinelli
- Preclinical Technologies; Aptuit, via Fleming 4 37135 Verona Italy
| | - Mauro Dacasto
- Dipartimento di Biomedicina Comparata e Alimentazione; Università di Padova; viale dell'Università 16 I-35020 Legnaro (Padova) Italy
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von Schönfels W, von Kampen O, Patsenker E, Stickel F, Schniewind B, Hinz S, Ahrens M, Balschun K, Egberts JH, Richter K, Landrock A, Sipos B, Will O, Huebbe P, Schreiber S, Nothnagel M, Röcken C, Rimbach G, Becker T, Hampe J, Schafmayer C. Metabolic signature of electrosurgical liver dissection. PLoS One 2013; 8:e72022. [PMID: 24058442 PMCID: PMC3772850 DOI: 10.1371/journal.pone.0072022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 07/07/2013] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND AND AIMS High frequency electrosurgery has a key role in the broadening application of liver surgery. Its molecular signature, i.e. the metabolites evolving from electrocauterization which may inhibit hepatic wound healing, have not been systematically studied. METHODS Human liver samples were thus obtained during surgery before and after electrosurgical dissection and subjected to a two-stage metabolomic screening experiment (discovery sample: N = 18, replication sample: N = 20) using gas chromatography/mass spectrometry. RESULTS In a set of 208 chemically defined metabolites, electrosurgical dissection lead to a distinct metabolic signature resulting in a separation in the first two dimensions of a principal components analysis. Six metabolites including glycolic acid, azelaic acid, 2-n-pentylfuran, dihydroactinidiolide, 2-butenal and n-pentanal were consistently increased after electrosurgery meeting the discovery (p<2.0 × 10(-4)) and the replication thresholds (p<3.5 × 10(-3)). Azelaic acid, a lipid peroxidation product from the fragmentation of abundant sn-2 linoleoyl residues, was most abundant and increased 8.1-fold after electrosurgical liver dissection (preplication = 1.6 × 10(-4)). The corresponding phospholipid hexadecyl azelaoyl glycerophosphocholine inhibited wound healing and tissue remodelling in scratch- and proliferation assays of hepatic stellate cells and cholangiocytes, and caused apoptosis dose-dependently in vitro, which may explain in part the tissue damage due to electrosurgery. CONCLUSION Hepatic electrosurgery generates a metabolic signature with characteristic lipid peroxidation products. Among these, azelaic acid shows a dose-dependent toxicity in liver cells and inhibits wound healing. These observations potentially pave the way for pharmacological intervention prior liver surgery to modify the metabolic response and prevent postoperative complications.
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Affiliation(s)
- Witigo von Schönfels
- Department of General and Thoracic Surgery, University Hospital Schleswig-Holstein, Kiel, Germany
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Wallgren M, Beranova L, Pham QD, Linh K, Lidman M, Procek J, Cyprych K, Kinnunen PKJ, Hof M, Gröbner G. Impact of oxidized phospholipids on the structural and dynamic organization of phospholipid membranes: a combined DSC and solid state NMR study. Faraday Discuss 2013; 161:499-513; discussion 563-89. [PMID: 23805755 DOI: 10.1039/c2fd20089a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Membranes undergo severe changes under oxidative stress conditions due to the creation of oxidized phospholipid (OxPL) species, which possess molecular properties quite different from their parental lipid components. These OxPLs play crucial roles in various pathological disorders and their occurrence is involved in the onset of intrinsic apoptosis, a fundamental pathway in programmed mammalian cell death. However, the molecular mechanisms by which these lipids can exert their apoptotic action via their host membranes (e.g., altering membrane protein function) are poorly understood. Therefore, we studied the impact of OxPLs on the organization and biophysical properties of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) based lipid membranes by differential scanning calorimetry (DSC) and solid state nuclear magnetic resonance (NMR) spectroscopy. Incorporation of defined OxPLs with either a carboxyl group (1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazePC)) or aldehyde (1-palmitoyl-(9'oxononanoyl)-sn-glycero-3-phosphocholine (PoxnoPC)) at their truncated sn-2-chain ends enabled us to reveal OxPL species-dependent differences. The calorimetric studies revealed significant effects of OxPLs on the thermotropic phase behavior of DMPC bilayers, especially at elevated levels where PazePC induced more pronounced effects than PoxnoPC. Temperature-dependent changes in the solid state 31P NMR spectra, which provided information of the lipid headgroup region in these mixed membrane systems, reflected this complex phase behavior. In the temperature region between 293 K (onset of the Lalpha-phase) and 298 K, two overlapping NMR spectra were visible which reflect the co-existence of two liquid-crystalline lamellar phases with presumably one reflecting OxPL-poor domains and the other OxPL-rich domains. Deconvolution of the DSC profiles also revealed these two partially overlapping thermal events. In addition, a third thermal, non-NMR-visible, event occurred at low temperatures, which can most likely be associated to a solid-phase mixing/demixing process of the OxPL-containing membranes. The observed phase transitions were moved to higher temperatures in the presence of heavy water due its condensing effect, where additional wideline 2H-NMR studies revealed a complex hydration pattern in the presence of OxPLs.
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Affiliation(s)
- Marcus Wallgren
- Department of Chemistry, Umeå University, Umeå, Sweden SE-901 87
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Mazereeuw G, Herrmann N, Bennett SAL, Swardfager W, Xu H, Valenzuela N, Fai S, Lanctôt KL. Platelet activating factors in depression and coronary artery disease: a potential biomarker related to inflammatory mechanisms and neurodegeneration. Neurosci Biobehav Rev 2013; 37:1611-21. [PMID: 23800745 DOI: 10.1016/j.neubiorev.2013.06.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 05/07/2013] [Accepted: 06/13/2013] [Indexed: 02/02/2023]
Abstract
The persistence of a depressive episode in coronary artery disease (CAD) patients not only heightens the risk of acute ischemic events, but it is also associated with accelerated cognitive decline. Antidepressant interventions for depression in CAD have only modest effects and novel approaches are limited by a poor understanding of etiological mechanisms. This review proposes that the platelet activating factor (PAF) family of lipids might be associated with the persistence of a depressive episode and related neurodegenerative pathology in CAD due to their association with leading etiological mechanisms for depression in CAD such as inflammation, oxidative and nitrosative stress, vascular endothelial dysfunction, and platelet reactivity. The evidence implicating PAFs in CAD, vascular pathology, and neurodegenerative processes is also presented. We also propose future directions for the investigation of PAFs as mediators of persistent depression. In summary, PAFs are implicated in leading mechanisms associated with depression in CAD. PAFs may therefore be associated with the persistence of depression in CAD and related to neurodegenerative and cognitive sequelae.
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Affiliation(s)
- Graham Mazereeuw
- Sunnybrook Research Institute, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada; Neural Regeneration Laboratory, Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada; CIHR Training Program in Neurodegenerative Lipidomics, Canada
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Bioactive lipids-based pH sensitive micelles for co-delivery of doxorubicin and ceramide to overcome multidrug resistance in leukemia. Pharm Res 2013; 30:2902-16. [PMID: 23793993 DOI: 10.1007/s11095-013-1121-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 06/11/2013] [Indexed: 12/11/2022]
Abstract
PURPOSE Construction of a novel PEGylated bioactive lipids-based micelle system for co-delivery of doxorubicin (DOX) and short chain ceramide (C6-ceramide) to overcome multidrug resistance in leukemia. METHODS The PEGylated bioactive lipids-based micelle system was constructed via electrostatic and hydrophobic interactions among DOX, bioactive lipids PazPC and C6-ceramide. The micellar formulation was characterized in terms of size, zeta potential, stability and release behavior, etc., and in vitro cytotoxicity, in vivo antitumor efficacy and the underlying mechanism were further evaluated. RESULTS This novel micellar system showed small size (~15 nm), high drug encapsulation efficiency (>90%), good stability and endosomal acid-triggered release of DOX. Synergistic cytotoxic effects between DOX and bioactive lipid C6-ceramide in P-gp overexpressing drug resistant leukemia P388/ADR cells were observed. The mechanistic studies demonstrated that modulation of drug efflux system and induction of apoptotic effects by lipids were responsible for the synergistic effects between DOX and C6-ceramide in drug resistant leukemia P388/ADR cells. Using an in-vivo P388/ADR leukemia mouse model, the median survival time of the DOX-loaded PEGylated micelles with PazPC and C6-ceramide as major components was significantly greater than that of free DOX and control group. CONCLUSIONS We developed a novel pH sensitive bioactive lipids-based micellar formulation which could potentially be useful in delivering chemotherapeutic drug DOX and provide a novel strategy to increase the therapeutic index for drug resistant leukemia treatment.
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Volinsky R, Kinnunen PKJ. Oxidized phosphatidylcholines in membrane-level cellular signaling: from biophysics to physiology and molecular pathology. FEBS J 2013; 280:2806-16. [PMID: 23506295 DOI: 10.1111/febs.12247] [Citation(s) in RCA: 271] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 01/15/2013] [Accepted: 02/27/2013] [Indexed: 11/26/2022]
Abstract
The oxidation of lipids has been shown to impact virtually all cellular processes. The paradigm has been that this involvement is due to interference with the functions of membrane-associated proteins. It is only recently that methodological advances in molecular-level detection and identification have begun to provide insights into oxidative lipid modification and its involvement in cell signaling as well as in major diseases and inflammation. Extensive evidence suggests a correlation between lipid peroxidation and degenerative neurological diseases such as Parkinson's and Alzheimer's, as well as type 2 diabetes and cancer. Despite the obvious relevance of understanding the molecular basis of the above ailments, the exact modes of action of oxidized lipids have remained elusive. In this minireview, we summarize recent findings on the biophysical characteristics of biomembranes following oxidative derivatization of their lipids, and how these altered properties are involved in both physiological processes and major pathological conditions. Lipid-bearing, oxidatively truncated and functionalized acyl chains are known to modify membrane bulk physical properties, such as thermal phase behavior, bilayer thickness, hydration and polarity profiles, as manifest in the altered structural dynamics of lipid bilayers, leading to augmented membrane permeability, fast lipid transbilayer diffusion (flip-flop), loss of lipid asymmetry (scrambling) and phase segregation (the formation of 'rafts'). These changes, together with the generated reactive lipid derivatives, can be further expected to interfere with lipid-protein interactions, influencing metabolic pathways, causing inflammation, the execution phase in apoptosis and initiating pathological processes.
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Affiliation(s)
- Roman Volinsky
- Helsinki Biophysics & Biomembrane Group, Department of Biomedical Engineering and Computational Science, Aalto University, Espoo, Finland
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Liu J, Li W, Chen R, McIntyre TM. Circulating biologically active oxidized phospholipids show on-going and increased oxidative stress in older male mice. Redox Biol 2013; 1:110-4. [PMID: 25499575 PMCID: PMC4802831 DOI: 10.1016/j.redox.2012.11.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 11/08/2012] [Accepted: 11/08/2012] [Indexed: 11/29/2022] Open
Abstract
Background The biologically active phospholipids Platelet-activating Factor (PAF) and oxidatively truncated phospholipids from chemical oxidation are increased in the circulation of rats subject to the oxidant stress of chronic ethanol ingestion. Potentially, circulating inflammatory and apoptotic phospholipids correlate to physiologic oxidative stress. Results PAF and the common oxidatively truncated and biologically active phospholipid azelaoyl phosphatidylcholine (Az-PC) were significantly increased in the plasma of older mice, and in male mice. PAF and Az-PC are very rapidly cleared from the circulation, which was unaffected by age or sex. Platelets exposed to Az-PC display phosphatidylserine on their surface, and occlusive platelet carotid arterial thrombosis is enhanced by aging. Conclusion Biologically active phospholipids vary in the circulation, with the highest levels being found in older, male mice. Turnover of PAF and the biologically active Az-PC are rapid and are invariant with age and sex, so increased production accounts for the increased concentration and flux of both lipids. Platelets are exposed to plasma Az-PC that depolarizes their mitochondria to increase pro-thrombotic phosphatidylserine expression, and occlusive platelet thrombosis is enhanced in aged mice. Significance Oxidatively modified phospholipids are increased in the circulation during common, mild oxidant stresses of aging, or in male compared to female animals. Turnover of these biologically active phospholipids by rapid transport into liver and kidney is unchanged, so circulating levels reflect continuously increased production.
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Affiliation(s)
- Jinbo Liu
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH 44195, USA; Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Wei Li
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH 44195, USA; Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Rui Chen
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Thomas M McIntyre
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH 44195, USA; Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
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Abstract
Free radical-induced oxidation of membrane phospholipids generates complex mixtures of oxidized phospholipids (oxPLs). The combinatorial operation of a few dozen reaction types on a few dozen phospholipid structures results in the production of a dauntingly vast diversity of oxPL molecular species. Structural identification of the individual oxPL in these mixtures is a redoubtable challenge that is absolutely essential to allow determination of the biological activities of individual species. With an emphasis on cardiovascular consequences, this Review focuses on biological activities of oxPLs whose molecular structures are known and highlights 2 diametrically opposite approaches that were used to determine those structures, that is, (1) the classic approach from bioactivity of a complex mixture to isolation and structural characterization of the active molecule followed by confirmation of the structure by unambiguous chemical synthesis and (2) hypothesis of products that are likely to be generated by lipid oxidation, followed by synthesis, and then detection in vivo guided by the availability of authentic standards, and last, characterization of biological activities. Especially important for the application of the second paradigm is the capability of LC-MS/MS and derivatizations to selectively detect and quantify specific oxPL in complex mixtures, without the need for their isolation or complete separation. This technology can provide strong evidence for identity by comparisons with pure, well-characterized samples available by chemical syntheses. Those pure samples are critical for determining the biological activities attributable to specific molecular species of oxPLs in the complex mixtures generated in vivo as a consequence of oxidative stress.
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Affiliation(s)
- Robert G Salomon
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA.
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Nieto-Estévez V, Pignatelli J, Araúzo-Bravo MJ, Hurtado-Chong A, Vicario-Abejón C. A global transcriptome analysis reveals molecular hallmarks of neural stem cell death, survival, and differentiation in response to partial FGF-2 and EGF deprivation. PLoS One 2013; 8:e53594. [PMID: 23308259 PMCID: PMC3538603 DOI: 10.1371/journal.pone.0053594] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 12/03/2012] [Indexed: 11/19/2022] Open
Abstract
Neurosphere cell culture is a commonly used model to study the properties and potential applications of neural stem cells (NSCs). However, standard protocols to culture NSCs have yet to be established, and the mechanisms underlying NSC survival and maintenance of their undifferentiated state, in response to the growth factors FGF-2 and EGF are not fully understood. Using cultures of embryonic and adult olfactory bulb stem cells (eOBSCs and aOBSCs), we analyzed the consequences of FGF-2 and EGF addition at different intervals on proliferation, cell cycle progression, cell death and differentiation, as well as on global gene expression. As opposed to cultures supplemented daily, addition of FGF-2 and EGF every 4 days significantly reduced the neurosphere volume and the total number of cells in the spheres, mainly due to increased cell death. Moreover, partial FGF-2 and EGF deprivation produced an increase in OBSC differentiation during the proliferative phase. These changes were more evident in aOBSC than eOBSC cultures. Remarkably, these effects were accompanied by a significant upregulation in the expression of endogenous Fgf-2 and genes involved in cell death and survival (Cryab), lipid catabolic processes (Pla2g7), cell adhesion (Dscaml1), cell differentiation (Dscaml1, Gpr17, S100b, Ndrg2) and signal transduction (Gpr17, Ndrg2). These findings support that a daily supply of FGF-2 and EGF is critical to maintain the viability and the undifferentiated state of NSCs in culture, and they reveal novel molecular hallmarks of NSC death, survival and the initiation of differentiation.
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Affiliation(s)
- Vanesa Nieto-Estévez
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Jaime Pignatelli
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Marcos J. Araúzo-Bravo
- Laboratory of Computational Biology and Bioinformatics, Department of Cell and Developmental Biology, Max Planck Institute for Molecular Biomedicine, Muenster, Germany
| | - Anahí Hurtado-Chong
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Carlos Vicario-Abejón
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- * E-mail:
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Lee S, Birukov KG, Romanoski CE, Springstead JR, Lusis AJ, Berliner JA. Role of phospholipid oxidation products in atherosclerosis. Circ Res 2012; 111:778-99. [PMID: 22935534 DOI: 10.1161/circresaha.111.256859] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
There is increasing clinical evidence that phospholipid oxidation products (Ox-PL) play a role in atherosclerosis. This review focuses on the mechanisms by which Ox-PL interact with endothelial cells, monocyte/macrophages, platelets, smooth muscle cells, and HDL to promote atherogenesis. In the past few years major progress has been made in identifying these mechanisms. It has been recognized that Ox-PL promote phenotypic changes in these cell types that have long-term consequences for the vessel wall. Individual Ox-PL responsible for specific cellular effects have been identified. A model of the configuration of bioactive truncated Ox-PL within membranes has been developed that demonstrates that the oxidized fatty acid moiety protrudes into the aqueous phase, rendering it accessible for receptor recognition. Receptors and signaling pathways for individual Ox-PL species are now determined and receptor independent signaling pathways identified. The effects of Ox-PL are mediated both by gene regulation and transcription independent processes. It has now become apparent that Ox-PL affects multiple genes and pathways, some of which are proatherogenic and some are protective. However, at concentrations that are likely present in the vessel wall in atherosclerotic lesions, the effects promote atherogenesis. There have also been new insights on enzymes that metabolize Ox-PL and the significance of these enzymes for atherosclerosis. With the knowledge we now have of the regulation and effects of Ox-PL in different vascular cell types, it should be possible to design experiments to test the role of specific Ox-PL on the development of atherosclerosis.
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Affiliation(s)
- Sangderk Lee
- Department of Pathology, University of California-Los Angeles, MRL 4760, 675 Charles E. Young Dr. S., Los Angeles, CA 90095, USA
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The oxidized phospholipid PazePC modulates interactions between Bax and mitochondrial membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:2718-24. [DOI: 10.1016/j.bbamem.2012.06.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Revised: 05/31/2012] [Accepted: 06/05/2012] [Indexed: 01/01/2023]
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Latchoumycandane C, Marathe GK, Zhang R, McIntyre TM. Oxidatively truncated phospholipids are required agents of tumor necrosis factor α (TNFα)-induced apoptosis. J Biol Chem 2012; 287:17693-17705. [PMID: 22433871 DOI: 10.1074/jbc.m111.300012] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
TNFα generates reactive oxygen species (ROS) at the cell surface that induce cell death, but how ROS communicate to mitochondria and their specific apoptotic action(s) are both undefined. ROS oxidize phospholipids to hydroperoxides that are friable and fragment adjacent to the (hydro)peroxide function, forming truncated phospholipids, such as azelaoyl phosphatidylcholine (Az-PC). Az-PC is relatively soluble, and exogenous Az-PC rapidly enters cells to damage mitochondrial integrity and initiate intrinsic apoptosis. We determined whether this toxic phospholipid is formed within cells during TNFα stimulation in sufficient quantities to induce apoptosis and if they are essential in TNFα-induced cytotoxicity. We found that TNFα induced ROS formation and phospholipid peroxidation in Jurkat cells, and either chemical interference with NADPH oxidase activity or siRNA suppression of the NADPH oxidase-4 subunit blocked ROS accumulation and phospholipid peroxidation. Mass spectrometry showed that phospholipid peroxides and then Az-PC increased after TNFα exposure, whereas ROS inhibition abolished Az-PC accumulation and TNFα-induced cell death. Glutathione peroxidase-4 (GPx4), which specifically metabolizes lipid hydroperoxides, fell in TNFα-stimulated cells prior to death. Ectopic GPx4 overcame this, reduced peroxidized phospholipid accumulation, blocked Az-PC accumulation, and prevented death. Conversely, GPx4 siRNA knockdown enhanced phospholipid peroxidation, increasing TNFα-stimulated Az-PC formation and apoptosis. Truncated phospholipids were essential elements of TNFα-induced apoptosis because overexpression of PAFAH2 (a phospholipase A(2) that selectively hydrolyzes truncated phospholipids) blocked TNFα-induced Az-PC accumulation without affecting phospholipid peroxidation. PAFAH2 also abolished apoptosis. Thus, phospholipid oxidation and truncation to apoptotic phospholipids comprise an essential element connecting TNFα receptor signaling to mitochondrial damage and apoptotic death.
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Affiliation(s)
- Calivarathan Latchoumycandane
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio 44195
| | - Gopal K Marathe
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio 44195
| | - Renliang Zhang
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio 44195
| | - Thomas M McIntyre
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio 44195.
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McIntyre TM. Bioactive oxidatively truncated phospholipids in inflammation and apoptosis: formation, targets, and inactivation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:2456-64. [PMID: 22445850 DOI: 10.1016/j.bbamem.2012.03.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 02/23/2012] [Accepted: 03/07/2012] [Indexed: 01/12/2023]
Abstract
This report reviews structurally related phospholipid oxidation products that are biologically active where molecular mechanisms have been defined. Phospholipids containing polyunsaturated fatty acyl residues are chemically or enzymatically oxidized to phospholipid hydroperoxides, which may fragment on either side of the newly introduced peroxy function to form phospholipids with a truncated sn-2 residue. These truncated phospholipids not subject to biologic control of their production and, depending on the sn-2 residue length and structure, can stimulate the plasma membrane receptor for PAF. Alternatively, these chemically formed products can be internalized by a transport system to either stimulate the lipid activated nuclear transcription factor PPARγ or at higher levels interact with mitochondria to initiate the intrinsic apoptotic cascade. Intracellular PAF acetylhydrolases specifically hydrolyze truncated phospholipids, and not undamaged, biosynthetic phospholipids, to protect cells from oxidative death. Truncated phospholipids are also formed within cells where they couple cytokine stimulation to mitochondrial damage and apoptosis. The relevance of intracellular truncated phospholipids is shown by the complete protection from cytokine induced apoptosis by PAF acetylhydrolase expression. This protection shows truncated phospholipids are the actual effectors of cytokine mediated toxicity. This article is part of a Special Issue entitled: Oxidized phospholipids-their properties and interactions with proteins.
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Gruber F, Bicker W, Oskolkova OV, Tschachler E, Bochkov VN. A simplified procedure for semi-targeted lipidomic analysis of oxidized phosphatidylcholines induced by UVA irradiation. J Lipid Res 2012; 53:1232-42. [PMID: 22414483 DOI: 10.1194/jlr.d025270] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Oxidized phospholipids (OxPLs) are increasingly recognized as signaling mediators that are not only markers of oxidative stress but are also "makers" of pathology relevant to disease pathogenesis. Understanding the biological role of individual molecular species of OxPLs requires the knowledge of their concentration kinetics in cells and tissues. In this work, we describe a straightforward "fingerprinting" procedure for analysis of a broad spectrum of molecular species generated by oxidation of the four most abundant species of polyunsaturated phosphatidylcholines (OxPCs). The approach is based on liquid-liquid extraction followed by reversed-phase HPLC coupled to electrospray ionization MS/MS. More than 500 peaks corresponding in retention properties to polar and oxidized PCs were detected within 8 min at 99 m/z precursor values using a single diagnostic product ion in extracts from human dermal fibroblasts. Two hundred seventeen of these peaks were fluence-dependently and statistically significantly increased upon exposure of cells to UVA irradiation, suggesting that these are genuine oxidized or oxidatively fragmented species. This method of semitargeted lipidomic analysis may serve as a simple first step for characterization of specific "signatures" of OxPCs produced by different types of oxidative stress in order to select the most informative peaks for identification of their molecular structure and biological role.
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Affiliation(s)
- Florian Gruber
- Department of Dermatology, Medical University of Vienna, Vienna, Austria
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41
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Yao Y, Harrison KA, Al-Hassani M, Murphy RC, Rezania S, Konger RL, Travers JB. Platelet-activating factor receptor agonists mediate xeroderma pigmentosum A photosensitivity. J Biol Chem 2012; 287:9311-21. [PMID: 22303003 DOI: 10.1074/jbc.m111.332395] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
To date, oxidized glycerophosphocholines (Ox-GPCs) with platelet-activating factor (PAF) activity produced non-enzymatically have not been definitively demonstrated to mediate any known disease processes. Here we provide evidence that these Ox-GPCs play a pivotal role in the photosensitivity associated with the deficiency of the DNA repair protein xeroderma pigmentosum type A (XPA). It should be noted that XPA-deficient cells are known to have decreased antioxidant defenses. These studies demonstrate that treatment of human XPA-deficient fibroblasts with the pro-oxidative stressor ultraviolet B (UVB) radiation resulted in increased reactive oxygen species and PAF receptor (PAF-R) agonistic activity in comparison with gene-corrected cells. The UVB irradiation-generated PAF-R agonists were inhibited by antioxidants. UVB irradiation of XPA-deficient (Xpa-/-) mice also resulted in increased PAF-R agonistic activity and skin inflammation in comparison with control mice. The increased UVB irradiation-mediated skin inflammation and TNF-α production in Xpa-/- mice were blocked by systemic antioxidants and by PAF-R antagonists. Structural characterization of PAF-R-stimulating activity in UVB-irradiated XPA-deficient fibroblasts using mass spectrometry revealed increased levels of sn-2 short-chain Ox-GPCs along with native PAF. These studies support a critical role for PAF-R agonistic Ox-GPCs in the pathophysiology of XPA photosensitivity.
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Affiliation(s)
- Yongxue Yao
- Department of Dermatology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
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42
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Vinaixa M, Rodriguez MA, Samino S, Díaz M, Beltran A, Mallol R, Bladé C, Ibañez L, Correig X, Yanes O. Metabolomics reveals reduction of metabolic oxidation in women with polycystic ovary syndrome after pioglitazone-flutamide-metformin polytherapy. PLoS One 2011; 6:e29052. [PMID: 22194988 PMCID: PMC3241700 DOI: 10.1371/journal.pone.0029052] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Accepted: 11/18/2011] [Indexed: 01/17/2023] Open
Abstract
Polycystic ovary syndrome (PCOS) is a variable disorder characterized by a broad spectrum of anomalies, including hyperandrogenemia, insulin resistance, dyslipidemia, body adiposity, low-grade inflammation and increased cardiovascular disease risks. Recently, a new polytherapy consisting of low-dose flutamide, metformin and pioglitazone in combination with an estro-progestagen resulted in the regulation of endocrine clinical markers in young and non-obese PCOS women. However, the metabolic processes involved in this phenotypic amelioration remain unidentified. In this work, we used NMR and MS-based untargeted metabolomics to study serum samples of young non-obese PCOS women prior to and at the end of a 30 months polytherapy receiving low-dose flutamide, metformin and pioglitazone in combination with an estro-progestagen. Our results reveal that the treatment decreased the levels of oxidized LDL particles in serum, as well as downstream metabolic oxidation products of LDL particles such as 9- and 13-HODE, azelaic acid and glutaric acid. In contrast, the radiuses of small dense LDL and large HDL particles were substantially increased after the treatment. Clinical and endocrine-metabolic markers were also monitored, showing that the level of HDL cholesterol was increased after the treatment, whereas the level of androgens and the carotid intima-media thickness were reduced. Significantly, the abundance of azelaic acid and the carotid intima-media thickness resulted in a high degree of correlation. Altogether, our results reveal that this new polytherapy markedly reverts the oxidant status of untreated PCOS women, and potentially improves the pro-atherosclerosis condition in these patients.
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Affiliation(s)
- Maria Vinaixa
- Metabolomics Platform of the Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders, Rovira i Virgili University, Tarragona, Spain
- Institut d'Investigació Sanitària Pere Virgili, Reus, Spain
- * E-mail: (MV); (OY)
| | - Miguel Angel Rodriguez
- Metabolomics Platform of the Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders, Rovira i Virgili University, Tarragona, Spain
- Institut d'Investigació Sanitària Pere Virgili, Reus, Spain
| | - Sara Samino
- Metabolomics Platform of the Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders, Rovira i Virgili University, Tarragona, Spain
- Institut d'Investigació Sanitària Pere Virgili, Reus, Spain
| | - Marta Díaz
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, Barcelona, Spain
- Endocrinology Unit, Hospital Sant Joan de Déu-Universitat de Barcelona, Esplugues de Llobregat, Spain
| | - Antoni Beltran
- Metabolomics Platform of the Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders, Rovira i Virgili University, Tarragona, Spain
| | - Roger Mallol
- Metabolomics Platform of the Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders, Rovira i Virgili University, Tarragona, Spain
- Institut d'Investigació Sanitària Pere Virgili, Reus, Spain
| | - Cinta Bladé
- Metabolomics Platform of the Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders, Rovira i Virgili University, Tarragona, Spain
- Institut d'Investigació Sanitària Pere Virgili, Reus, Spain
| | - Lourdes Ibañez
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, Barcelona, Spain
- Endocrinology Unit, Hospital Sant Joan de Déu-Universitat de Barcelona, Esplugues de Llobregat, Spain
| | - Xavier Correig
- Metabolomics Platform of the Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders, Rovira i Virgili University, Tarragona, Spain
- Institut d'Investigació Sanitària Pere Virgili, Reus, Spain
| | - Oscar Yanes
- Metabolomics Platform of the Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders, Rovira i Virgili University, Tarragona, Spain
- * E-mail: (MV); (OY)
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Wang Y, Chen L, Ding Y, Yan W. Oxidized phospholipid based pH sensitive micelles for delivery of anthracyclines to resistant leukemia cells in vitro. Int J Pharm 2011; 422:409-17. [PMID: 22037443 DOI: 10.1016/j.ijpharm.2011.10.029] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 10/07/2011] [Accepted: 10/17/2011] [Indexed: 11/17/2022]
Abstract
A self-assembled micelle drug delivery system was constructed with an oxidized phospholipid for anthracycline anti-cancer drug delivery. An oxidized phospholipid, 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazPC), was chosen to fabricate micelles via both electrostatic and hydrophobic interactions for delivery of doxorubicin (DOX) and idarubicin (IDA). The formation of ion-pair complexes between PazPC and DOX was first investigated under different pH conditions. Drug-loaded PazPC micelles at a 5:1 molar ratio of lipid/drug at pH 7.0 were then prepared by the solvent evaporation method. The empty and drug-loaded PazPC micelles exhibited a small particle size (∼10 nm) and high encapsulation efficiency. In vitro stability and release profile indicated that the micelles were stable at physiological conditions, but exhibited pH-sensitive behavior with accelerated release of DOX or IDA in an acidic endosome environment. Finally, in vitro uptake and cytotoxicity were evaluated for leukemia P388 and its resistant subline P388/ADR. The drug-loaded PazPC micelles enhanced drug uptake and exhibited higher cytotoxicity in both leukemia cells in comparison to free drugs. In conclusion, we developed a novel pH sensitive oxidized phospholipid-based micellar formulation which could potentially be useful in delivering anthracycline anti-cancer drugs and provide a novel strategy for increasing the therapeutic index while overcoming multidrug resistance for leukemia treatment.
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Affiliation(s)
- Yongzhong Wang
- Department of Pharmacal Sciences, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
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44
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Volinsky R, Cwiklik L, Jurkiewicz P, Hof M, Jungwirth P, Kinnunen PKJ. Oxidized phosphatidylcholines facilitate phospholipid flip-flop in liposomes. Biophys J 2011; 101:1376-84. [PMID: 21943418 DOI: 10.1016/j.bpj.2011.07.051] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Revised: 07/15/2011] [Accepted: 07/26/2011] [Indexed: 12/19/2022] Open
Abstract
Lipid asymmetry is a ubiquitous property of the lipid bilayers in cellular membranes and its maintenance and loss play important roles in cell physiology, such as blood coagulation and apoptosis. The resulting exposure of phosphatidylserine on the outer surface of the plasma membrane has been suggested to be caused by a specific membrane enzyme, scramblase, which catalyzes phospholipid flip-flop. Despite extensive research the role of scramblase(s) in apoptosis has remained elusive. Here, we show that phospholipid flip-flop is efficiently enhanced in liposomes by oxidatively modified phosphatidylcholines. A combination of fluorescence spectroscopy and molecular dynamics simulations reveal that the mechanistic basis for this property of oxidized phosphatidylcholines is due to major changes imposed by the oxidized phospholipids on the biophysical properties of lipid bilayers, resulting in a fast cross bilayer diffusion of membrane phospholipids and loss of lipid asymmetry, requiring no scramblase protein.
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Affiliation(s)
- Roman Volinsky
- Helsinki Biophysics and Biomembrane Group, Department of Biomedical Engineering and Computational Science, Aalto University, Espoo, Finland
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45
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Long JZ, Cisar JS, Milliken D, Niessen S, Wang C, Trauger SA, Siuzdak G, Cravatt BF. Metabolomics annotates ABHD3 as a physiologic regulator of medium-chain phospholipids. Nat Chem Biol 2011; 7:763-5. [PMID: 21926997 PMCID: PMC3201731 DOI: 10.1038/nchembio.659] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 07/08/2011] [Indexed: 01/08/2023]
Abstract
All organisms, including humans, possess a huge number of uncharacterized enzymes. Here, we describe a general cell-based screen for enzyme substrate discovery by untargeted metabolomics and its application to identify α/β-hydrolase domain-containing 3 (ABHD3) as a lipase that selectively cleaves medium-chain and oxidatively-truncated phospholipids. Abhd3−/− mice possess elevated myristoyl (C14)-phospholipids, including the bioactive lipid C14-lysophosphatidylcholine, confirming the physiological relevance of our substrate assignments.
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46
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Page S, Chandhoke V, Baranova A. Melanin and melanogenesis in adipose tissue: possible mechanisms for abating oxidative stress and inflammation? Obes Rev 2011; 12:e21-31. [PMID: 20576005 DOI: 10.1111/j.1467-789x.2010.00773.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Obesity has become a worldwide epidemic and can lead to multiple chronic diseases. Adipose tissue is increasingly thought to play an active role in obesity-related pathologies such as insulin resistance and non-alcoholic fatty liver disease. Obesity has been strongly associated with systemic inflammation and, to a lesser degree, with oxidative stress, although the causal relationships among these factors are unclear. A recent study demonstrating an expression of the components of the melanogenic pathway and the presence of melanin in visceral adipose has raised questions regarding the possible role of melanogenesis in adipose tissue. As this study also found larger amounts of melanin in the adipose tissue of obese patients relative to lean ones, we hypothesize that melanin, a pigment known for its antioxidant and anti-inflammatory properties, may scavenge reactive oxygen species and abate oxidative stress and inflammation in adipose tissue. This review considers the evidence to support such a hypothesis, and speculates on the role of melanin within adipocytes. Furthermore, we consider whether the α-melanocyte-stimulating hormone or its synthetic analogues could be used to stimulate melanin production in adipocytes, should the hypothesis be supported in future experiments.
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Affiliation(s)
- S Page
- Department of Molecular and Microbiology, College of Science, George Mason University, Fairfax Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, VA, USA
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47
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Gehrau R, Maluf D, Archer K, Stravitz R, Suh J, Le N, Mas V. Molecular pathways differentiate hepatitis C virus (HCV) recurrence from acute cellular rejection in HCV liver recipients. Mol Med 2011; 17:824-33. [PMID: 21519635 DOI: 10.2119/molmed.2011.00072] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 04/19/2011] [Indexed: 12/11/2022] Open
Abstract
Acute cellular rejection (ACR) and hepatitis C virus (HCV) recurrence (HCVrec) are common complications after liver transplantation (LT) in HCV patients, who share common clinical and histological features, making a differential diagnosis difficult. Fifty-three liver allograft samples from unique HCV LT recipients were studied using microarrays, including a training set (n = 32) and a validation set (n = 19). Two no-HCV-ACR samples from LT recipients were also included. Probe set intensity values were obtained using the robust multiarray average method (RMA) method. Analysis of variance identified statistically differentially expressed genes (P ≤ 0.005). The limma package was used to fit the mixed-effects models using a restricted maximum likelihood procedure. The last absolute shrinkage and selection operator (LASSO) model was fit with HCVrec versus ACR as the dependent variable predicted. N-fold cross-validation was performed to provide an unbiased estimate of generalization error. A total of 179 probe sets were differentially expressed among groups, with 71 exclusive genes between HCVrec and HCV-ACR. No differences were found within ACR group (HCV-ACR vs. no-HCV-ACR). Supervised clustering analysis displayed two clearly independent groups, and no-HCV-ACR clustered within HCV-ACR. HCVrec-related genes were associated with a cytotoxic T-cell profile, and HCV-ACR-related genes were associated with the inflammatory response. The best-fitting LASSO model classifier accuracy, including 15 genes, has an accuracy of 100% in the training set. N-fold cross-validation accuracy was 78.1%, and sensitivity, specificity and positive and negative predictive values were 50.0%, 90.9%, 71.4% and 80.0%, respectively. Arginase type II (ARG2), ethylmalonic encephalopathy 1 (ETHE1), transmembrane protein 176A (TMEM176A) and TMEM176B genes were significantly confirmed in the validation set. A molecular signature capable of distinguishing HCVrec and ACR in HCV LT recipients was identified and validated.
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Affiliation(s)
- Ricardo Gehrau
- Department of Surgery, Virginia Commonwealth University, Richmond, Virginia, USA
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Chen R, Brady E, McIntyre TM. Human TMEM30a promotes uptake of antitumor and bioactive choline phospholipids into mammalian cells. THE JOURNAL OF IMMUNOLOGY 2011; 186:3215-25. [PMID: 21289302 DOI: 10.4049/jimmunol.1002710] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Antitumor alkylphospholipids initiate apoptosis in transformed HL-60 and Jurkat cells while sparing their progenitors. 1-O-Alkyl-2-carboxymethyl-sn-glycero-3-phosphocholine (Edelfosine) like other short-chained phospholipids--inflammatory platelet-activating factor (PAF) and apoptotic oxidatively truncated phospholipids--are proposed to have intracellular sites of action, yet a conduit for these choline phospholipids into mammalian cells is undefined. Edelfosine is also accumulated by Saccharomyces cerevisiae in a process requiring the membrane protein Lem3p, and the human genome contains a Lem3p homolog TMEM30a. We show that import of choline phospholipids into S. cerevisiae ΔLem3 is partially reconstituted by human TMEM30a and by Lem3p-TMEM30a chimeras, showing the proteins are orthologous. TMEM30a-GFP chimeras expressed in mammalian cells localized in plasma membranes, as well as internal organelles, and ectopic TMEM30a expression promoted uptake of exogenous choline and ethanolamine phospholipids. Short hairpin RNA knockdown of TMEM30a reduced fluorescent choline phospholipid and [(3)H]PAF import. This knockdown also reduced mitochondrial depolarization from exogenous Edelfosine or the mitotoxic oxidatively truncated phospholipid azelaoyl phosphatidylcholine, and the knockdown reduced apoptosis in response to these two phospholipids. These results show that extracellular choline phospholipids with short sn-2 residues can have intracellular roles and sites of metabolism because they are transport substrates for a TMEM30a phospholipid import system. Variation in this mechanism could limit sensitivity to short chain choline phospholipids such as Edelfosine, PAF, and proapoptotic phospholipids.
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Affiliation(s)
- Rui Chen
- Department of Cell Biology, Cleveland Clinic, Cleveland, OH 44195, USA
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49
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Effect of oxidized phosphatidylcholine on biomarkers of oxidative stress in rats. Indian J Clin Biochem 2011; 26:154-60. [PMID: 22468042 DOI: 10.1007/s12291-010-0064-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Accepted: 03/05/2010] [Indexed: 10/18/2022]
Abstract
In this study it was planned to investigate the effect of oxidized phosphatidylcholine (derived from egg) feeding on lipid peroxidation of different tissues in rats. Male Wistar albino rats were fed oxidized and unoxidized phosphatidylcholine for 2 and 4 weeks, respectively. During the period of study food intake and body weights of animals increased gradually. Animals fed oxidized phosphatidylcholine for 2 and 4 weeks showed 33 and 15% spontaneous hemolysis of red blood cells in vitro. Under identical experimental conditions animals given unoxidized phosphatidylcholine showed 14.5 and 13.4% hemolysis for 2 and 4 week's period, respectively. Thiobarbituric acid reactive substances (TBARS) level in thymus, spleen, kidney, heart, liver and lung significantly increased in rats given oxidized phosphatidylcholine as compared to unoxidized group. Furthermore, in oxidized phosphatidylcholine group TBARS values in kidney, liver and lungs continued to rise for 4 weeks of treatment while TBARS level in heart, spleen and thymus was found to be decreased at the end of 4 weeks of oxidized phosphatidylcholine feeding. Plasma triacylglycerol and cholesterol was found to increase in rats who had received oxidized phosphatidylcholine for 2 weeks. These findings suggest that excess and persistent intake of oxidized phosphatidylcholine can cause significant damage to organs.
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50
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Liu J, Chen R, Marathe GK, Febbraio M, Zou W, McIntyre TM. Circulating platelet-activating factor is primarily cleared by transport, not intravascular hydrolysis by lipoprotein-associated phospholipase A2/ PAF acetylhydrolase. Circ Res 2010; 108:469-77. [PMID: 21183738 DOI: 10.1161/circresaha.110.228742] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
RATIONALE The phospholipid platelet-activating factor (PAF) stimulates all cells of the innate immune system and numerous cardiovascular cells. A single enzyme (plasma PAF acetylhydrolase [PAF-AH] or lipoprotein-associated phospholipase [Lp-PL]A(2)) in plasma hydrolyzes PAF, but significant controversy exists whether its action is pro- or antiinflammatory and accordingly whether its inhibition will slow cardiovascular disease. OBJECTIVE We sought to define how PAF and related short-chain oxidized phospholipids turnover in vivo and the role of PAF acetylhydrolase/Lp-PLA(2) in this process. METHODS AND RESULTS [(3)H-acetyl]PAF was hydrolyzed by murine or human plasma (t(1/2), 3 and 7 minutes, respectively), but injected [(3)H-acetyl]PAF disappeared from murine circulation more quickly (t(1/2), <30 seconds). [(3)H]PAF clearance was unchanged in PAF receptor(-/-) animals, or over the first 2 half-lives in PAF-AH(-/-) animals. [(3)H]PAF turnover was reduced by coinjecting excess unlabeled PAF or an oxidatively truncated phospholipid, and [(3)H]PAF clearance was slowed in hyperlipidemic apolipoprotein (apo)E(-/-) mice with excess circulating oxidatively truncated phospholipids. [(3)H]PAF, fluorescent NBD-PAF, or fluorescent oxidatively truncated phospholipid were primarily accumulated by liver and lung, and were transported into endothelium as intact phospholipids through a common mechanism involving TMEM30a. CONCLUSIONS Circulating PAF and oxidized phospholipids are continually and rapidly cleared, and hence continually and rapidly produced. Saturable PAF receptor-independent transport, rather than just intravascular hydrolysis, controls circulating inflammatory and proapoptotic oxidized phospholipid mediators. Intravascular PAF has access to intracellular compartments. Inflammatory and proapoptotic phospholipids may accumulate in the circulation as transport is overwhelmed by substrates in hyperlipidemia.
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Affiliation(s)
- Jinbo Liu
- Department of Cell Biology, NE10, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, Cleveland, OH 44195, USA
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