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Sherratt SCR, Mason RP, Libby P, Steg PG, Bhatt DL. Do patients benefit from omega-3 fatty acids? Cardiovasc Res 2024; 119:2884-2901. [PMID: 38252923 PMCID: PMC10874279 DOI: 10.1093/cvr/cvad188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/11/2023] [Accepted: 09/26/2023] [Indexed: 01/24/2024] Open
Abstract
Omega-3 fatty acids (O3FAs) possess beneficial properties for cardiovascular (CV) health and elevated O3FA levels are associated with lower incident risk for CV disease (CVD.) Yet, treatment of at-risk patients with various O3FA formulations has produced disparate results in large, well-controlled and well-conducted clinical trials. Prescription formulations and fish oil supplements containing low-dose mixtures of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have routinely failed to prevent CV events in primary and secondary prevention settings when added to contemporary care, as shown most recently in the STRENGTH and OMEMI trials. However, as observed in JELIS, REDUCE-IT, and RESPECT-EPA, EPA-only formulations significantly reduce CVD events in high-risk patients. The CV mechanism of action of EPA, while certainly multifaceted, does not depend solely on reductions of circulating lipids, including triglycerides (TG) and LDL, and event reduction appears related to achieved EPA levels suggesting that the particular chemical and biological properties of EPA, as compared to DHA and other O3FAs, may contribute to its distinct clinical efficacy. In vitro and in vivo studies have shown different effects of EPA compared with DHA alone or EPA/DHA combination treatments, on atherosclerotic plaque morphology, LDL and membrane oxidation, cholesterol distribution, membrane lipid dynamics, glucose homeostasis, endothelial function, and downstream lipid metabolite function. These findings indicate that prescription-grade, EPA-only formulations provide greater benefit than other O3FAs formulations tested. This review summarizes the clinical findings associated with various O3FA formulations, their efficacy in treating CV disease, and their underlying mechanisms of action.
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Affiliation(s)
- Samuel C R Sherratt
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
- Elucida Research LLC, Beverly, MA, USA
| | - R Preston Mason
- Elucida Research LLC, Beverly, MA, USA
- Department of Medicine, Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Peter Libby
- Department of Medicine, Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Ph Gabriel Steg
- Université Paris-Cité, INSERM_UMR1148/LVTS, FACT (French Alliance for Cardiovascular Trials), Assistance Publique–Hôpitaux de Paris, Hôpital Bichat, Paris, France
| | - Deepak L Bhatt
- Mount Sinai Fuster Heart Hospital, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, NewYork 10029-5674, NY, USA
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2
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Sherratt SCR, Libby P, Dawoud H, Bhatt DL, Malinski T, Mason RP. Eicosapentaenoic acid (EPA) reduces pulmonary endothelial dysfunction and inflammation due to changes in protein expression during exposure to particulate matter air pollution. Biomed Pharmacother 2023; 162:114629. [PMID: 37027984 DOI: 10.1016/j.biopha.2023.114629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 03/27/2023] [Accepted: 03/29/2023] [Indexed: 04/09/2023] Open
Abstract
AIMS Inhalation of air pollution small particle matter (PM) is a leading cause of cardiovascular (CV) disease. Exposure to PMs causes endothelial cell (EC) dysfunction as evidenced by nitric oxide (NO) synthase uncoupling, vasoconstriction and inflammation. Eicosapentaenoic acid (EPA) has been shown to mitigate PM-induced adverse cardiac changes in patients receiving omega-3 fatty acid supplementation. We set out to determine the pro-inflammatory effects of multiple PMs (urban and fine) on pulmonary EC NO bioavailability and protein expression, and whether EPA restores EC function under these conditions. METHODS AND RESULTS We pretreated pulmonary ECs with EPA and then exposed them to urban or fine air pollution PMs. LC/MS-based proteomic analysis to assess relative expression levels. Expression of adhesion molecules was measured by immunochemistry. The ratio of NO to peroxynitrite (ONOO-) release, an indication of eNOS coupling, was measured using porphyrinic nanosensors following calcium stimulation. Urban/fine PMs also modulated 9/12 and 13/36 proteins, respectively, linked to platelet and neutrophil degranulation pathways and caused > 50% (p < 0.001) decrease in the stimulated NO/ONOO- release ratio. EPA treatment altered expression of proteins involved in these inflammatory pathways, including a decrease in peroxiredoxin-5 and an increase in superoxide dismutase-1. EPA also increased expression of heme oxygenase-1 (HMOX1), a cytoprotective protein, by 2.1-fold (p = 0.024). EPA reduced elevations in sICAM-1 levels by 22% (p < 0.01) and improved the NO/ONOO- release ratio by > 35% (p < 0.05). CONCLUSION These cellular changes may contribute to anti-inflammatory, cytoprotective and lipid changes associated with EPA treatment during air pollution exposure.
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Affiliation(s)
- Samuel C R Sherratt
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA; Elucida Research LLC, Beverly, MA, USA
| | - Peter Libby
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Hazem Dawoud
- Nanomedical Research Laboratory, Ohio University, Athens, OH, USA
| | - Deepak L Bhatt
- Mount Sinai Heart, Icahn School of Medicine at Mount Sinai Health System, New York, NY, USA
| | - Tadeusz Malinski
- Nanomedical Research Laboratory, Ohio University, Athens, OH, USA.
| | - R Preston Mason
- Elucida Research LLC, Beverly, MA, USA; Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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Sherratt SCR. REDUCE-IT, Biomarkers, and Confirmation Bias: Are We Missing the Forest for the Trees? Eur J Prev Cardiol 2023:7167219. [PMID: 37195316 DOI: 10.1093/eurjpc/zwad169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 05/15/2023] [Indexed: 05/18/2023]
Affiliation(s)
- Samuel C R Sherratt
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
- Elucida Research, Beverly, MA 01915
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Sherratt SCR, Libby P, Bhatt DL, Mason RP. Comparative Effects of Mineral Oil, Corn Oil, Eicosapentaenoic Acid, and Docosahexaenoic Acid in an In Vitro Atherosclerosis Model. J Am Heart Assoc 2023; 12:e029109. [PMID: 36942760 PMCID: PMC10122895 DOI: 10.1161/jaha.122.029109] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 02/17/2023] [Indexed: 03/23/2023]
Affiliation(s)
- Samuel C. R. Sherratt
- Department of Molecular, Cellular, and Biomedical SciencesUniversity of New HampshireDurhamNHUSA
- Elucida Research LLCBeverlyMAUSA
| | - Peter Libby
- Department of Medicine, Cardiovascular Division, Brigham and Women’s HospitalHarvard Medical SchoolBostonMAUSA
| | - Deepak L. Bhatt
- Mount Sinai HeartIcahn School of Medicine at Mount SinaiNew YorkNYUSA
| | - R. Preston Mason
- Elucida Research LLCBeverlyMAUSA
- Department of Medicine, Cardiovascular Division, Brigham and Women’s HospitalHarvard Medical SchoolBostonMAUSA
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Sherratt SCR. Letter by Sherratt Regarding Article, "Effects of Randomized Treatment With Icosapent Ethyl and a Mineral Oil Comparator on Interleukin-1β, Interleukin-6, C-Reactive Protein, Oxidized Low-Density Lipoprotein Cholesterol, Homocysteine, Lipoprotein(a), and Lipoprotein-Associated Phospholipase A2: A REDUCE-IT Biomarker Substudy". Circulation 2022; 146:e282-e283. [PMID: 36374970 DOI: 10.1161/circulationaha.122.061919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Samuel C R Sherratt
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham. Employed by Elucida Research, Beverly, MA
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Sherratt SCR, Libby P, Bhatt DL, Mason RP. A biological rationale for the disparate effects of omega-3 fatty acids on cardiovascular disease outcomes. Prostaglandins Leukot Essent Fatty Acids 2022; 182:102450. [PMID: 35690002 DOI: 10.1016/j.plefa.2022.102450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/09/2022] [Accepted: 05/19/2022] [Indexed: 12/29/2022]
Abstract
The omega-3 fatty acids (n3-FAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) rapidly incorporate into cell membranes where they modulate signal transduction pathways, lipid raft formation, and cholesterol distribution. Membrane n3-FAs also form specialized pro-resolving mediators and other intracellular oxylipins that modulate inflammatory pathways, including T-cell differentiation and gene expression. Cardiovascular (CV) trials have shown that EPA, administered as icosapent ethyl (IPE), reduces composite CV events, along with plaque volume, in statin-treated, high-risk patients. Mixed EPA/DHA regimens have not shown these benefits, perhaps as the result of differences in formulation, dosage, or potential counter-regulatory actions of DHA. Indeed, EPA and DHA have distinct, tissue-specific effects on membrane structural organization and cell function. This review summarizes: (1) results of clinical outcome and imaging trials using n3-FA formulations; (2) membrane interactions of n3-FAs; (3) effects of n3-FAs on membrane oxidative stress and cholesterol crystalline domain formation during hyperglycemia; (4) n3-FA effects on endothelial function; (5) role of n3-FA-generated metabolites in inflammation; and (6) ongoing and future clinical investigations exploring treatment targets for n3-FAs, including COVID-19.
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Affiliation(s)
- Samuel C R Sherratt
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH 03823, USA; Elucida Research LLC, Beverly, MA 01915-0091, USA
| | - Peter Libby
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115-6110, USA
| | - Deepak L Bhatt
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115-6110, USA
| | - R Preston Mason
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115-6110, USA; Elucida Research LLC, Beverly, MA 01915-0091, USA.
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Mason SD, Sherratt SCR, Kruguer SM, Muthersbaugh M, Harris JP, Gatlin WC, Topp JD, Keller GS. Multi-scale analysis of habitat fragmentation on small-mammal abundance and tick-borne pathogen infection prevalence in Essex County, MA. PLoS One 2022; 17:e0269768. [PMID: 35696376 PMCID: PMC9191718 DOI: 10.1371/journal.pone.0269768] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 05/27/2022] [Indexed: 12/02/2022] Open
Abstract
Habitat fragmentation and heterogeneity transform otherwise contiguous tracks of forest into smaller patches in the northeastern U.S. and likely impact abundances, movement patterns, and disease transmission pathways for small-mammal communities at multiple scales. We sought to determine the structure of a small-mammal community in terms of mammal abundance and infection prevalence of Borrelia burgdorferi sensu stricto (s.s.), Anaplasma phagocytophilum, and Babesia microti within a fragmented landscape in Essex County, Massachusetts, USA. We studied communities at multiple spatial scales, including vegetation, edge type, and landscape (including 200-m, 500-m, and 1000-m radii) scales. A total of 16 study sites were chosen to represent four edge types: interior forest, pasture edge, natural edge, and residential edge. At each site, we trapped small mammals and conducted vegetation surveys and GIS analysis. Upon capture, a tissue sample was collected to analyze for presence of pathogens. Northern short-tailed shrew (Blarina brevicauda) abundance did not differ based on edge type, whereas abundance of the white-footed mouse (Peromyscus leucopus) was greatest at pasture edges, although the relationship was relatively weak. White-footed mouse abundance was negatively associated with amount of forested area within a 500-m radius, whereas northern short-tailed shrew abundance demonstrated a positive relationship with fragmentation indices at the 200-m radius. White-footed mice captured at interior-forest habitat were more likely be infected with B. burgdorferi (s.s.) than individuals from edge habitat. Greater prevalence of B. burgdorferi infection of white-footed mice in forest interiors compared to edge habitats counters previous studies. Reasons for this and implications are discussed.
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Affiliation(s)
- Samuel D. Mason
- Landscape Ecology Lab, Department of Biology, Gordon College, Wenham, Massachusetts, United States of America
| | - Samuel C. R. Sherratt
- Landscape Ecology Lab, Department of Biology, Gordon College, Wenham, Massachusetts, United States of America
| | - Samantha M. Kruguer
- Landscape Ecology Lab, Department of Biology, Gordon College, Wenham, Massachusetts, United States of America
| | - Michael Muthersbaugh
- Landscape Ecology Lab, Department of Biology, Gordon College, Wenham, Massachusetts, United States of America
| | - Jonathan P. Harris
- Landscape Ecology Lab, Department of Biology, Gordon College, Wenham, Massachusetts, United States of America
- Department of Integrative Biology, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - Wayne C. Gatlin
- Department of Biology, Endicott College, Beverly, Massachusetts, United States of America
| | - Justin D. Topp
- Landscape Ecology Lab, Department of Biology, Gordon College, Wenham, Massachusetts, United States of America
| | - Gregory S. Keller
- Landscape Ecology Lab, Department of Biology, Gordon College, Wenham, Massachusetts, United States of America
- * E-mail:
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Abstract
Despite cardiovascular disease (CVD) reductions with high-intensity statins, there remains residual risk among patients with metabolic disorders. Alongside low-density lipoproteins (LDL-C), elevated triglycerides (TG) are associated with incident CVD events. Omega-3 fatty acids (n3-FAs), specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), lower TG levels, but their ability to reduce CV risk has been highly inconsistent. Trials using icosapent ethyl (IPE), a purified EPA ethyl ester, produced reductions in CVD events and atherosclerotic plaque regression compared with mixed EPA/DHA formulations despite similar TG-reductions. The separate effects of EPA and DHA on tissue distribution, oxidative stress, inflammation, membrane structure and endothelial function may contribute to these discordant outcomes. Additional mechanistic trials will provide further insights into the role of n3-FAs in reducing CVD risk beyond TG lowering.
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Affiliation(s)
- R Preston Mason
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| | - Samuel C R Sherratt
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03823, USA
| | - Robert H Eckel
- Division of Endocrinology, Metabolism & Diabetes, Division of Cardiology, University of Colorado Anschutz Medical Campus, 1635 Aurora Court, Aurora, CO 80045, USA
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Mason RP, Sherratt SCR, Eckel RH. Rationale for different formulations of omega-3 fatty acids leading to differences in residual cardiovascular risk reduction. Metabolism 2022; 130:155161. [PMID: 35151755 DOI: 10.1016/j.metabol.2022.155161] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 02/03/2022] [Accepted: 02/04/2022] [Indexed: 12/13/2022]
Affiliation(s)
- R Preston Mason
- Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, United States of America.
| | | | - Robert H Eckel
- University of Colorado Anschutz Medical Campus, Aurora, CO 80045, United States of America
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Sherratt SCR, Libby P, Bhatt DL, Dawoud H, Malinski T, Mason RP. Omega-3 fatty acids differentially alter the expression of detoxification enzymes and nitric oxide bioavailability in endothelial cells during IL-6 exposure. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.3368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Atherosclerotic plaques can elaborate reactive oxygen species (ROS) that reduce nitric oxide (NO) bioavailability. Cellular detoxification enzymes including various peroxiredoxin (PRDX) and superoxide dismutase (SOD) isoforms can inactivate ROS. The omega-3 fatty acid (n3-FA) eicosapentaenoic acid (EPA) reduced cardiovascular (CV) events in high-risk patients (REDUCE-IT), a benefit not observed with mixed n3-FAs containing docosahexaenoic acid (DHA).
Purpose
The purpose of this study was to compare the effects of EPA and DHA on NO bioavailability and expression of detoxification enzymes in the vascular endothelium in vitro.
Methods
Human umbilical vein endothelial cells (HUVECs) were pretreated with EPA or DHA at equimolar levels (10 μM) for 2 h, then challenged with IL-6 at 12 ng/ml for 24 h. Proteomic analysis was performed using LC/MS to measure relative protein expression. Only significant (p<0.05) changes between treatment groups >1-fold were analyzed. Cells were stimulated with calcium ionophore to measure NO and peroxynitrite (ONOO-) release using a porphyrinic nanosensor.
Results
EPA, but not DHA, augmented PRDX-2 and SOD1 expression in HUVECs relative to IL-6 alone (1.2-fold and 1.6-fold, respectively, p=0.03). EPA also significantly lowered other isoforms unlike DHA. Either EPA or DHA increased thioredoxin expression by 1.5-fold (p=0.001) and 1.3-fold (p=0.02), respectively and decreased SOD2 expression by 1.5-fold (p=8.75E-11) and 1.6-fold (p=6.03E-9), respectively. IL-6 alone only increased expression of 6 detoxification enzymes by at least 1.2-fold, relative to vehicle. Unlike DHA, EPA also increased the NO to ONOO- release ratio by 36% (p<0.05) relative to IL-6 alone, without changes in NO synthase (eNOS) expression.
Conclusions
n3-FAs differentially influenced NO bioavailability and expression of ROS detoxification proteins, including peroxiredoxin and SOD isoforms. The net benefits of EPA on eNOS function and ROS detoxification may contribute to reduced atherothrombotic risk compared to DHA.
Funding Acknowledgement
Type of funding sources: Private company. Main funding source(s): Amarin Pharma Inc., Elucida Research
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Affiliation(s)
- S C R Sherratt
- Elucida Research LLC, Biophysics Department, Beverly, MA, United States of America
| | - P Libby
- Brigham and Women'S Hospital, Harvard Medical School, Boston, United States of America
| | - D L Bhatt
- Brigham and Women'S Hospital, Harvard Medical School, Boston, United States of America
| | - H Dawoud
- Ohio University, Department of Chemistry and Biochemistry, Athens, OH, United States of America
| | - T Malinski
- Ohio University, Department of Chemistry and Biochemistry, Athens, OH, United States of America
| | - R P Mason
- Brigham and Women'S Hospital, Harvard Medical School, Boston, United States of America
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11
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Sherratt SCR, Libby P, Dawoud H, Bhatt DL, Malinski T, Mason RP. Eicosapentaenoic acid inhibits lipopolysaccharide (LPS)-induced nitrite production and cytokine release from J774 macrophages. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.3351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Eicosapentaenoic acid (EPA), an omega-3 (ω-3) fatty acid, reduced cardiovascular (CV) events in high-risk patients (REDUCE-IT) but the mechanism is not fully understood. Activated macrophages, characterized by cytokine release and increased inducible nitric oxide synthase (iNOS) activity, contribute to atherosclerosis. As both a substrate for and potential inhibitor of cyclooxygenase (COX), EPA may reduce iNOS activity.
Purpose
The purpose of this study was to evaluate the dose-dependent effects of EPA on nitrite and cytokine release from lipopolysaccharide (LPS)-activated macrophages.
Methods
Murine J774 macrophages were pretreated with vehicle or EPA at 10, 20 and 40 μM for 2 h, then challenged with LPS at 1.0 μg/ml. After 24 hr, iNOS activity was measured by nitrite production using the Griess assay. EPA was compared to the COX inhibitor diclofenac at 1.0 μg/ml. Levels of interleukin-1β (IL-1β) and tumor necrosis factor alpha (TNF-α) in cell supernatant were measured by immunochemistry using colchicine as a positive control.
Results
Activated macrophages caused a >4-fold increase in nitrite production (p<0.001) that was reduced by EPA in a dose-dependent manner. EPA decreased nitrite levels by 40, 62 and 77% at 10, 20 and 40 μM, respectively (p<0.01). Diclofenac separately reduced nitrite levels by 40% (p<0.01). EPA also reduced expression of IL-1β and TNF-α by 40% and 31%, respectively (p<0.01), in a manner similar to equimolar colchicine (10 μM). The reductions in IL-1β and TNF-α with EPA were dose-dependent.
Conclusions
EPA reduced macrophage activation as evidenced by decreased nitrite production and cytokine release similar to other anti-inflammatory agents. These findings indicate a novel effect of EPA on mechanisms of inflammation associated with vascular disease.
Funding Acknowledgement
Type of funding sources: Private company. Main funding source(s): Amarin Pharma Inc., Elucida Research
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Affiliation(s)
- S C R Sherratt
- Elucida Research LLC, Biophysics Department, Beverly, MA, United States of America
| | - P Libby
- Brigham and Women'S Hospital, Harvard Medical School, Boston, United States of America
| | - H Dawoud
- Ohio University, Department of Chemistry and Biochemistry, Athens, OH, United States of America
| | - D L Bhatt
- Brigham and Women'S Hospital, Harvard Medical School, Boston, United States of America
| | - T Malinski
- Ohio University, Department of Chemistry and Biochemistry, Athens, OH, United States of America
| | - R P Mason
- Brigham and Women'S Hospital, Harvard Medical School, Boston, United States of America
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Sherratt SCR, Libby P, Bhatt DL, Dawoud H, Malinski T, Mason RP. Omega-3 fatty acids differentially reduced expression of neutrophil degranulation-associated proteins in endothelial cells during IL-6 exposure. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.3369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Neutrophil degranulation contributes to atherogenesis and tissue injury. Mixed omega-3 fatty acid (n3-FA) formulations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have failed to reduce CV events compared to EPA only (REDUCE-IT), but the mechanisms are not understood.
Purpose
The purpose of this study was to compare the effects of EPA and DHA on expression of proteins linked to neutrophil degranulation in the vascular endothelium in vitro.
Methods
Human umbilical vein endothelial cells (HUVECs) were pretreated with EPA or DHA at equimolar levels (10 μM) for 2 h, then challenged with IL-6 at 12 ng/ml for 24 h. Proteomic analysis was performed using LC/MS to measure relative protein expression. Only significant (p<0.05) changes between treatment groups >1-fold were analyzed.
Results
In the Reactome “neutrophil degranulation” pathway, EPA and DHA downregulated 27 and 14 proteins, respectively, (p=9.97E-9 and 5.30E-4, respectively) relative to IL-6 alone. There were 12 protein changes common to both n3-FAs, including heme oxygenase-2 and ferritin light chain. EPA downregulated 15 proteins unlike DHA, including peroxiredoxin-6 and mitogen-activated protein kinase-1 (MAPK1). A combined 21 proteins downregulated by EPA and DHA versus IL-6 were upregulated by IL-6 alone relative to vehicle. EPA also increased expression of Rho-associated protein kinase-1 (ROCK-1), a protein downregulated by IL-6 alone and unaffected by DHA.
Conclusions
EPA and DHA differentially modulated expression of proteins linked to neutrophil degranulation. The distinct effects of EPA on protein expression may contribute to reduced inflammation in vascular injury compared to DHA.
Funding Acknowledgement
Type of funding sources: Private company. Main funding source(s): Amarin Pharma Inc., Elucida Research
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Affiliation(s)
- S C R Sherratt
- Elucida Research LLC, Biophysics Department, Beverly, MA, United States of America
| | - P Libby
- Brigham and Women'S Hospital, Harvard Medical School, Boston, United States of America
| | - D L Bhatt
- Brigham and Women'S Hospital, Harvard Medical School, Boston, United States of America
| | - H Dawoud
- Ohio University, Department of Chemistry and Biochemistry, Athens, OH, United States of America
| | - T Malinski
- Ohio University, Department of Chemistry and Biochemistry, Athens, OH, United States of America
| | - R P Mason
- Brigham and Women'S Hospital, Harvard Medical School, Boston, United States of America
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Sherratt SCR, Dawoud H, Bhatt DL, Malinski T, Mason RP. Omega-3 and omega-6 fatty acids have distinct effects on endothelial fatty acid content and nitric oxide bioavailability. Prostaglandins Leukot Essent Fatty Acids 2021; 173:102337. [PMID: 34464785 DOI: 10.1016/j.plefa.2021.102337] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 08/16/2021] [Accepted: 08/16/2021] [Indexed: 12/26/2022]
Abstract
Treatment with high dose icosapent ethyl (IPE), an ethyl ester of the omega-3 fatty acid eicosapentaenoic acid (EPA), significantly reduced ischemic events in patients with either cardiovascular disease (CV) or diabetes plus other risk factors (REDUCE-IT) but the mechanism is not well understood. We compared the effects of EPA, docosahexaenoic acid (DHA), and the omega-6 fatty acid arachidonic acid (AA) on bioavailability of nitric oxide (NO) and fatty acid composition. Human umbilical vein endothelial cells (HUVECs) were pretreated with EPA, DHA, or AA (10 µM). Cells were stimulated with calcium ionophore and NO and peroxynitrite (ONOO-) were measured using porphyrinic nanosensors. Levels of EPA, DHA, AA and other fatty acids were measured by gas chromatography (GC). EPA treatment caused the greatest NO release (18%, p < 0.001) and reduction in ONOO- (13%, p < 0.05) compared to control; the [NO]/[ ONOO-] ratio increased by 35% (p < 0.001). DHA treatment increased NO levels by 12% (p < 0.01) but had no effect on ONOO- release. AA did not affect either NO or ONOO- release. Fatty acid treatments increased their respective levels in endothelial cells. EPA levels increased 10-fold to 4.59 mg/g protein (p < 0.001) with EPA treatment and the EPA/AA ratio increased by 10-fold (p < 0.001) compared to vehicle. Only EPA increased docosapentaenoic acid (DPA, omega-3) levels by 2-fold (p < 0.001). AA alone decreased the EPA/AA ratio 4-fold (p<0.001). These findings support a preferential benefit of EPA on endothelial function and omega-3 fatty acid content.
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Affiliation(s)
- Samuel C R Sherratt
- Elucida Research LLC, Beverly, MA 01915-0091, United States; Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, United States
| | - Hazem Dawoud
- Nanomedical Research Laboratory, Ohio University, Athens, OH 45701, United States
| | - Deepak L Bhatt
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115-6110, United States
| | - Tadeusz Malinski
- Nanomedical Research Laboratory, Ohio University, Athens, OH 45701, United States
| | - R Preston Mason
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115-6110, United States; Elucida Research LLC, Beverly, MA 01915-0091, United States.
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Sherratt SCR, Juliano RA, Copland C, Bhatt DL, Libby P, Mason RP. EPA and DHA containing phospholipids have contrasting effects on membrane structure. J Lipid Res 2021; 62:100106. [PMID: 34400132 PMCID: PMC8430377 DOI: 10.1016/j.jlr.2021.100106] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 07/21/2021] [Accepted: 07/30/2021] [Indexed: 11/26/2022] Open
Abstract
Omega-3 FAs EPA and DHA influence membrane fluidity, lipid rafts, and signal transduction. A clinical trial, Reduction of Cardiovascular Events with Icosapent Ethyl—Intervention Trial, demonstrated that high-dose EPA (4 g/d icosapent ethyl) reduced composite cardiovascular events in statin-treated high-risk patients. EPA benefits correlated with on-treatment levels, but similar trials using DHA-containing formulations did not show event reduction. We hypothesized that differences in clinical efficacy of various omega-3 FA preparations could result from differential effects on membrane structure. To test this, we used small-angle X-ray diffraction to compare 1-palmitoyl-2-eicosapentaenoyl-sn-glycero-3-phosphocholine (PL-EPA), 1-palmitoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (PL-DHA), and 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (PL-AA) in membranes with and without 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and cholesterol. Electron density profiles (electrons/Å3 vs. Å) were used to determine membrane structure, including membrane width (d-space). PL-EPA and PL-DHA had similar membrane structures without POPC and/or cholesterol but had contrasting effects in the presence of POPC and cholesterol. PL-EPA increased membrane hydrocarbon core electron density over an area of ±0–10 Å from the center, indicating an extended orientation. PL-DHA increased electron density in the phospholipid head group region, concomitant with disordering in the hydrocarbon core and a similar d-space (58 Å). Adding equimolar amounts of PL-EPA and PL-DHA produced changes that were attenuated compared with their separate effects. PL-AA increased electron density centered ±12 Å from the membrane center. The contrasting effects of PL-EPA, PL-DHA, and PL-AA on membrane structure may contribute to differences observed in the biological activities and clinical actions of various omega-3 FAs.
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Affiliation(s)
- Samuel C R Sherratt
- Elucida Research LLC, Beverly, MA, USA; Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | | | | | - Deepak L Bhatt
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Peter Libby
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - R Preston Mason
- Elucida Research LLC, Beverly, MA, USA; Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
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15
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Il'Giovine ZJ, Williams JB, Mason RP, Sherratt SCR, Hsich EM, Lever H, Mehra MR, Starling RC. Kinetics of generic tacrolimus in heart transplantation: A cautionary note. J Heart Lung Transplant 2021; 40:569-572. [PMID: 33903017 DOI: 10.1016/j.healun.2021.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/02/2021] [Accepted: 03/10/2021] [Indexed: 10/21/2022] Open
Abstract
Tacrolimus is a core component of immunosuppressive regimens. This study compared active pharmaceutical ingredient (API) and dissolution kinetics of branded tacrolimus and formulations from three generic manufacturers (Mylan, Dr. Reddy's, Intas) including samples from patients who suffered acute cardiac allograft rejection. Generic samples showed similar API content compared to branded samples with no major impurities. Capsules that underwent uniformity testing had consistent capsule-to-capsule API. Dissolution testing showed similar profiles between branded tacrolimus and Mylan, but notable differences with Dr. Reddy's and Intas. The approximate maximal inhibitory concentration (IC50) was highest in branded tacrolimus (29 minutes), followed by Mylan (26 minutes), Dr. Reddy's (19 minutes), and Intas (14 minutes) (Student-Newman-Keuls Multiple Comparisons Test; overall ANOVA: p = 0.0199, F = 6.469). This study suggests that the bioavailability of certain generic tacrolimus formulations peak significantly earlier than branded tacrolimus. Further study is needed to determine whether these differences are clinically relevant.
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Affiliation(s)
- Zachary J Il'Giovine
- Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Kaufman Center for Heart Failure Treatment and Recovery, Cleveland Clinic Foundation, Cleveland, Ohio
| | - J Bradley Williams
- Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Kaufman Center for Heart Failure Treatment and Recovery, Cleveland Clinic Foundation, Cleveland, Ohio
| | - R Preston Mason
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; Elucida Research LLC, Beverly, Massachusetts
| | - Samuel C R Sherratt
- Elucida Research LLC, Beverly, Massachusetts; Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, New Hampshire
| | - Eileen M Hsich
- Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Kaufman Center for Heart Failure Treatment and Recovery, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Harry Lever
- Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Kaufman Center for Heart Failure Treatment and Recovery, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Mandeep R Mehra
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Randall C Starling
- Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Kaufman Center for Heart Failure Treatment and Recovery, Cleveland Clinic Foundation, Cleveland, Ohio.
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Sherratt SCR, Juliano RA, Mason RP. Eicosapentaenoic acid (EPA) has optimal chain length and degree of unsaturation to inhibit oxidation of small dense LDL and membrane cholesterol domains as compared to related fatty acids in vitro. Biochim Biophys Acta Biomembr 2020; 1862:183254. [PMID: 32135144 DOI: 10.1016/j.bbamem.2020.183254] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 02/14/2020] [Accepted: 02/29/2020] [Indexed: 11/25/2022]
Abstract
BACKGROUND Oxidation of small dense low-density lipoprotein (sdLDL) and membranes is causally related to atherosclerosis. The omega-3 fatty acid (FA) eicosapentaenoic acid (EPA, 20:5, ω-3) significantly reduced oxidized LDL in patients with hypertriglyceridemia by unknown mechanisms. We compared EPA effects to related FAs of varying chain length and unsaturation on oxidation of sdLDL and model membranes, and on cholesterol crystal domains. We compared EPA to the FAs: stearic (SA, 18:0), oleic (OA, 18:1, ω-9), linoleic (LA, 18:2, ω-6), alpha-linolenic (ALA, 18:3, ω-3), eicosanoic (EA, 20:0), eicosatrienoic (ETE, 20:3, ω-3), arachidonic (AA, 20:4, ω-6), docosapentaenoic (DPA, 22:5, ω-3), and docosahexaenoic (DHA, 22:6, ω-3). METHODS Human sdLDL or model membranes of cholesterol and 1,2-Dilinoleoyl-sn-glycero-3-phosphocholine [18:2(cis)PC or DLPC] were preincubated with FAs followed by copper-induced oxidation. Malondialdehyde (MDA) or lipid hydroperoxides (LOOH) levels measured oxidation; small-angle X-ray diffraction assessed cholesterol domain formation. RESULTS After 40 min, EPA reduced MDA levels 70% compared to vehicle (p < 0.001). Lesser inhibition was observed with DHA, DPA, ETE, and ALA (33%, 34%, 32%, and 16%, respectively; all p < 0.001 versus vehicle). Similar relative FA effects were observed in model membranes where EPA more substantially inhibited cholesterol crystal domain formation. CONCLUSION We observed relationships between hydrocarbon length and unsaturation with antioxidant activity and membrane cholesterol domain formation. EPA had the most favorable molecular structure, likely contributing to membrane stability, improved lipoprotein clearance, and reduced inflammation. GENERAL SIGNIFICANCE Insight is provided into FA hydrocarbon length and unsaturation relationships with antioxidant activity in lipoproteins and membranes, and cholesterol crystal domains formation.
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Affiliation(s)
| | | | - R Preston Mason
- Elucida Research LLC, Beverly, MA 01915-0091, USA; Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115-6110, USA.
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Sherratt SCR, Villeneuve P, Durand E, Mason RP. Rosmarinic acid and its esters inhibit membrane cholesterol domain formation through an antioxidant mechanism based, in nonlinear fashion, on alkyl chain length. Biochim Biophys Acta Biomembr 2019; 1861:550-555. [PMID: 30582915 DOI: 10.1016/j.bbamem.2018.12.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 11/28/2018] [Accepted: 12/20/2018] [Indexed: 01/07/2023]
Abstract
BACKGROUND Under conditions of oxidative stress, cholesterol aggregates into discrete membrane bilayer domains that precipitate the formation of extracellular crystals, a feature of advanced atheroma in cardiovascular disease. Therapeutic interventions using membrane-directed antioxidants, such as polyphenolic esters, may reduce cholesterol domains and crystal formation. In this study, the effects of rosmarinic acid (RC0) and rosmarinic esters, with alkyl chain lengths ranging from 4 to 16‑carbons (RC4-RC16), on membrane lipid oxidation and cholesterol domain formation were investigated. METHODS Model membranes were prepared with 1,2-dilinoleoyl-sn-glycero-3-phosphocholine and cholesterol at different cholesterol-to-phospholipid mole ratios (0.3:1, 0.9:1, and 1.2:1), in the absence or presence of each molecule and exposed to 72 h of oxidation. Changes in lipid hydroperoxide (LOOH) and cholesterol domain formation were measured using iodometric and small angle x-ray diffraction approaches, respectively. RESULTS Rosmarinic acid and its esters had differential effects on LOOH formation based on alkyl chain length. RC8 exhibited the greatest antioxidant effect, reducing LOOH levels by 82%, and inhibited cholesterol domain formation. By contrast, RC0 and RC16 failed to inhibit either LOOH formation or cholesterol domain formation. CONCLUSION These data indicate that the membrane antioxidant and cholesterol domain inhibition activities of rosmarinic acid esters are dependent, nonlinearly, on alkyl chain length. The mechanism for this effect is attributed to the influence of alkyl chain length on the optimal depth of the polyphenols into the lipid bilayer for trapping free radicals. GENERAL SIGNIFICANCE These findings provide insight into novel atheroprotective benefits of polyphenol esters that are dependent on their membrane location.
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Affiliation(s)
| | - Pierre Villeneuve
- CIRAD, UMR IATE, Montpellier F-34398, France; IATE, Univ Montpellier, CIRAD, INRA, Montpellier SupAgro, Montpellier, France
| | - Erwann Durand
- CIRAD, UMR IATE, Montpellier F-34398, France; IATE, Univ Montpellier, CIRAD, INRA, Montpellier SupAgro, Montpellier, France
| | - R Preston Mason
- Elucida Research, Beverly, MA 01915-0091, USA; Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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Mason RP, Dawoud H, Jacob RF, Sherratt SCR, Malinski T. Eicosapentaenoic acid improves endothelial function and nitric oxide bioavailability in a manner that is enhanced in combination with a statin. Biomed Pharmacother 2018; 103:1231-1237. [PMID: 29864903 DOI: 10.1016/j.biopha.2018.04.118] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 04/04/2018] [Accepted: 04/16/2018] [Indexed: 11/27/2022] Open
Abstract
The endothelium exerts many vasoprotective effects that are largely mediated by release of nitric oxide (NO). Endothelial dysfunction represents an early but reversible step in atherosclerosis and is characterized by a reduction in the bioavailability of NO. Previous studies have shown that eicosapentaenoic acid (EPA), an omega-3 fatty acid (O3FA), and statins individually improve endothelial cell function, but their effects in combination have not been tested. Through a series of in vitro experiments, this study evaluated the effects of a combined treatment of EPA and the active metabolite of atorvastatin (ATM) on endothelial cell function under conditions of oxidative stress. Specifically, the comparative and time-dependent effects of these agents on endothelial dysfunction were examined by measuring the levels of NO and peroxynitrite (ONOO-) released from human umbilical vein endothelial cells (HUVECs). The data suggest that combined treatment with EPA and ATM is beneficial to endothelial function and was unique to EPA and ATM since similar improvements could not be recapitulated by substituting another O3FA docosahexaenoic acid (DHA) or other TG-lowering agents such as fenofibrate, niacin, or gemfibrozil. Comparable beneficial effects were observed when HUVECs were pretreated with EPA and ATM before exposure to oxidative stress. Interestingly, the kinetics of EPA-based protection of endothelial function in response to oxidation were found to be significantly different than those of DHA. Lastly, the beneficial effects on endothelial function generated by combined treatment of EPA and ATM were reproduced when this study was expanded to an ex vivo model utilizing rat glomerular endothelial cells. Taken together, these findings suggest that a combined treatment of EPA and ATM can inhibit endothelial dysfunction that occurs in response to conditions such as hyperglycemia, oxidative stress, and dyslipidemia.
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Affiliation(s)
- R Preston Mason
- Elucida Research LLC, Beverly, MA, 01915, United States; Cardiovascular Division, Department of Medicine, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, United States.
| | - Hazem Dawoud
- Nanomedical Research Laboratory, Ohio University, Athens, OH, 45701, United States
| | | | | | - Tadeusz Malinski
- Nanomedical Research Laboratory, Ohio University, Athens, OH, 45701, United States
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Sherratt SCR, Mason RP. Eicosapentaenoic acid and docosahexaenoic acid have distinct membrane locations and lipid interactions as determined by X-ray diffraction. Chem Phys Lipids 2018; 212:73-79. [PMID: 29355517 DOI: 10.1016/j.chemphyslip.2018.01.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 12/26/2017] [Accepted: 01/08/2018] [Indexed: 01/18/2023]
Abstract
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) differentially influence lipid oxidation, signal transduction, fluidity, and cholesterol domain formation, potentially due in part to distinct membrane interactions. We used small angle X-ray diffraction to evaluate the EPA and DHA effects on membrane structure. Membrane vesicles composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and cholesterol (C) (0.3C:POPC mole ratio) were prepared and treated with vehicle, EPA, or DHA (1:10 mol ratio to POPC). Electron density profiles generated from the diffraction data showed that EPA increased membrane hydrocarbon core electron density over a broad area, up to ± 20 Å from the membrane center, indicating an energetically favorable extended orientation for EPA likely stabilized by van der Waals interactions. By contrast, DHA increased electron density in the phospholipid head group region starting at ± 12 Å from the membrane center, presumably due to DHA-surface interactions, with coincident reduction in electron density in the membrane hydrocarbon core centered ± 7-9 Å from the membrane center. The membrane width (d-space) decreased by 5 Å in the presence of vehicle as the temperature increased from 10 °C to 30 °C due to increased acyl chain trans-gauche isomerizations, which was unaffected by addition of EPA or DHA. The influence of DHA on membrane structure was modulated by temperature changes while the interactions of EPA were unaffected. The contrasting EPA and DHA effects on membrane structure indicate distinct molecular locations and orientations that may contribute to observed differences in biological activity.
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Affiliation(s)
| | - R Preston Mason
- Elucida Research LLC, Beverly, MA, 01915-0091, USA; Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115-6110, USA.
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Sherratt SCR, Mason RP. Eicosapentaenoic acid inhibits oxidation of high density lipoprotein particles in a manner distinct from docosahexaenoic acid. Biochem Biophys Res Commun 2018; 496:335-338. [PMID: 29331380 DOI: 10.1016/j.bbrc.2018.01.062] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 01/09/2018] [Indexed: 10/18/2022]
Abstract
The omega-3 fatty acid eicosapentaenoic acid (EPA) reduces oxidation of ApoB-containing particles in vitro and in patients with hypertriglyceridemia. EPA may produce these effects through a potent antioxidant mechanism, which may facilitate LDL clearance and slow plaque progression. We hypothesize that EPA antioxidant effects may extend to ApoA-containing particles like HDL, potentially preserving certain atheroprotective functions. HDL was isolated from human plasma and incubated at 37 °C in the absence (vehicle) or presence of EPA and/or DHA; 5.0 or 10.0 μM each. Samples were then subjected to copper-induced oxidation (10 μM). HDL oxidation was inhibited similarly by EPA and DHA up to 1 h. EPA (10 μM) maintained significant HDL oxidation inhibition of 89% (0.622 ± 0.066 μM MDA; p < .001) at 4 h, with continued inhibition of 64% at 14 h, vs. vehicle (5.65 ± 0.06 to 2.01 ± 0.10 μM MDA; p < .001). Conversely, DHA (10 μM) antioxidant benefit was lost by 4 h. At a lower concentration (5 μM), EPA antioxidant activity remained at 81% (5.53 ± 0.15 to 1.03 ± 0.10 μM MDA; p < .001) at 6 h, while DHA lost all antioxidant activity by 4 h. The antioxidant activity of EPA was preserved when combined with an equimolar concentration of DHA (5 μM each). EPA pretreatment prevented HDL oxidation in a dose-dependent manner that was preserved over time. These results suggest unique lipophilic and electron stabilization properties for EPA as compared to DHA with respect to inhibition of HDL oxidation. These antioxidant effects of EPA may enhance certain atheroprotective functions for HDL.
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Affiliation(s)
| | - R Preston Mason
- Elucida Research LLC, Beverly, MA 01915-0091, USA; Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115-6110, USA.
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