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Omega-3 fatty acids ameliorate vascular inflammation: A rationale for their atheroprotective effects

      Highlights

      • Eicosapentaenoic acid (EPA) reduced expression of markers of acute vascular inflammation after inflammatory stimuli, in in vitro and in vivo models.
      • EPA reduced expression of markers of chronic vascular inflammation but not plaque burden, in an atherogenic mouse model.
      • Blood EPA and docosahexaenoic acid (DHA) levels correlated inversely with markers of vascular inflammation, with EPA having a stronger correlation.

      Abstract

      Background and aims

      Clinical trials have demonstrated reductions in major adverse cardiovascular events with purified high-dose eicosapentaenoic acid (EPA), independent of effects on lipids. We aimed to investigate whether omega-3 fatty acids reduce vascular inflammation, a critical mediator of atherosclerosis, and hypothesised that EPA is superior to docosahexaenoic acid (DHA).

      Methods

      In a double-blind randomised controlled trial and cell-culture study, 40 healthy volunteers were supplemented with 4 g daily of either EPA, DHA, fish oil (2:1 EPA:DHA), or placebo for 30 days. Serum was incubated with TNF-stimulated human umbilical vein endothelial cells (HUVECs), and markers of acute vascular inflammation (AVI) were measured. The effects of EPA, DHA (600 mg/kg/day), olive oil, or no treatment were also measured in preclinical models of [1] AVI using a periarterial collar (C57Bl/6J; n = 40 mice) and [2] atherosclerosis where ApoE−/− mice (n = 40) were fed a 16-week atherogenic diet.

      Results

      EPA supplementation reduced expression of C–C motif chemokine ligand 2 (CCL2) by 25% compared to placebo (p = 0.03). In the AVI model, EPA reduced vascular expression of VCAM1 by 43% (p = 0.02) and CCL2 by 41% (p = 0.03). Significant inverse correlations were observed between EPA levels and vascular expression of VCAM1 (r = −0.56, p = 0.001) and CCL2 (r = −0.56, p = 0.001). In ApoE−/- mice, EPA reduced aortic expression of Il1b by 44% (p = 0.04) and Tnf by 49% (p = 0.04), with similar inverse correlations between EPA levels and both Il1b (r = −0.63, p = 0.009) and Tnf (r = −0.50, p = 0.04).

      Conclusions

      Supplementation with EPA, more so than DHA, ameliorates acute and chronic vascular inflammation, providing a rationale for the cardiovascular benefit observed with high dose omega-3 fatty acid administration.

      Graphical abstract

      Keywords

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      References

        • Fruchart J.C.
        • Sacks F.
        • Hermans M.P.
        • Assmann G.
        • Brown W.V.
        • Ceska R.
        • et al.
        The Residual Risk Reduction Initiative: a call to action to reduce residual vascular risk in patients with dyslipidemia.
        Am. J. Cardiol. 2008; 102 (Nov 17): 1k-34k
        • Libby P.
        Inflammation in atherosclerosis.
        Arterioscler. Thromb. Vasc. Biol. 2012; 32 (Sep): 2045-2051
        • Geovanini G.R.
        • Libby P.
        Atherosclerosis and inflammation: overview and updates.
        Clin. Sci. 2018; 132 (Jun 9): 1243-1252
        • Ridker P.M.
        • Everett B.M.
        • Thuren T.
        • MacFadyen J.G.
        • Chang W.H.
        • Ballantyne C.
        • et al.
        Antiinflammatory therapy with canakinumab for atherosclerotic disease.
        N. Engl. J. Med. 2017; 377 (Sep 21): 1119-1131
        • Tardif J.C.
        • Kouz S.
        • Waters D.D.
        • Bertrand O.F.
        • Diaz R.
        • Maggioni A.P.
        • et al.
        Efficacy and safety of low-dose colchicine after myocardial infarction.
        N. Engl. J. Med. 2019; 381 (Dec 26): 2497-2505
        • Calder P.C.
        Marine omega-3 fatty acids and inflammatory processes: effects, mechanisms and clinical relevance.
        Biochim. Biophys. Acta. 2015; 1851 (Apr): 469-484
        • Sakai C.
        • Ishida M.
        • Ohba H.
        • Yamashita H.
        • Uchida H.
        • Yoshizumi M.
        • et al.
        Fish oil omega-3 polyunsaturated fatty acids attenuate oxidative stress-induced DNA damage in vascular endothelial cells.
        PloS One. 2017; 12e0187934
        • Serhan C.N.
        • Petasis N.A.
        Resolvins and protectins in inflammation resolution.
        Chem. Rev. 2011; 111 (Oct 12): 5922-5943
        • Zheng J.
        • Huang T.
        • Yu Y.
        • Hu X.
        • Yang B.
        • Li D.
        Fish consumption and CHD mortality: an updated meta-analysis of seventeen cohort studies.
        Publ. Health Nutr. 2012; 15 (Apr): 725-737
        • Burr M.L.
        • Fehily A.M.
        • Gilbert J.F.
        • Rogers S.
        • Holliday R.M.
        • Sweetnam P.M.
        • et al.
        Effects of changes in fat, fish, and fibre intakes on death and myocardial reinfarction: diet and reinfarction trial (DART).
        Lancet (London, England). 1989; 2 (Sep 30): 757-761
        • Yokoyama M.
        • Origasa H.
        • Matsuzaki M.
        • Matsuzawa Y.
        • Saito Y.
        • Ishikawa Y.
        • et al.
        Effects of eicosapentaenoic acid on major coronary events in hypercholesterolaemic patients (JELIS): a randomised open-label, blinded endpoint analysis.
        Lancet (London, England). 2007; 369 (Mar 31): 1090-1098
        • Bhatt D.L.
        • Steg P.G.
        • Miller M.
        • Brinton E.A.
        • Jacobson T.A.
        • Ketchum S.B.
        • et al.
        Cardiovascular risk reduction with icosapent ethyl for hypertriglyceridemia.
        N. Engl. J. Med. 2019; 380: 11-22
        • Mayer K.
        • Merfels M.
        • Muhly-Reinholz M.
        • Gokorsch S.
        • Rosseau S.
        • Lohmeyer J.
        • et al.
        Omega-3 fatty acids suppress monocyte adhesion to human endothelial cells: role of endothelial PAF generation.
        Am. J. Physiol. Heart Circ. Physiol. 2002; 283 (Aug): H811-H818
        • De Caterina R.
        • Cybulsky M.I.
        • Clinton S.K.
        • Gimbrone Jr., M.A.
        • Libby P.
        The omega-3 fatty acid docosahexaenoate reduces cytokine-induced expression of proatherogenic and proinflammatory proteins in human endothelial cells.
        Arterioscler. Thromb. : J. Vasc. Biol. Am. Heart Assoc. 1994; 14 (Nov): 1829-1836
        • Baker E.J.
        • Yusof M.H.
        • Yaqoob P.
        • Miles E.A.
        • Calder P.C.
        Omega-3 fatty acids and leukocyte-endothelium adhesion: novel anti-atherosclerotic actions.
        Mol. Aspect. Med. 2018; 64 (Dec): 169-181
        • Liu G.
        • Muhlhausler B.S.
        • Gibson R.A.
        A method for long term stabilisation of long chain polyunsaturated fatty acids in dried blood spots and its clinical application.
        Prostaglandins Leukot. Essent. Fatty Acids. 2014; 91 (Dec): 251-260
        • Jiang Y.
        • Jiang L.L.
        • Maimaitirexiati X.M.
        • Zhang Y.
        • Wu L.
        Irbesartan attenuates TNF- 5 alpha-induced ICAM-1, VCAM-1, and E-selectin expression through suppression of NF-kappaB pathway in HUVECs.
        Eur. Rev. Med. Pharmacol. Sci. 2015; 19 (Sep): 3295-3302
        • Ashby D.T.
        • Rye K.A.
        • Clay M.A.
        • Vadas M.A.
        • Gamble J.R.
        • Barter P.J.
        Factors influencing the ability of HDL to inhibit expression of vascular cell adhesion molecule-1 in endothelial cells.
        Arterioscler. Thromb. Vasc. Biol. 1998; 18 (Sep): 1450-1455
        • Borissoff J.I.
        • Otten J.J.
        • Heeneman S.
        • Leenders P.
        • van Oerle R.
        • Soehnlein O.
        • et al.
        Genetic and pharmacological modifications of thrombin formation in apolipoprotein e- 14 deficient mice determine atherosclerosis severity and atherothrombosis onset in a neutrophil-dependent manner.
        PloS One. 2013; 8e55784
        • von der Thusen J.H.
        • van Berkel T.J.
        • Biessen E.A.
        Induction of rapid atherogenesis by perivascular carotid collar placement in apolipoprotein E-deficient and low-density lipoprotein receptor-deficient mice.
        Circulation. 2001; 103 (Feb 27): 1164-1170
        • Manavis J.
        • Gilham P.
        • Davies R.
        • Ruszkiewicz A.
        The immunohistochemical detection of mismatch repair gene proteins (MLH1, MSH2, MSH6, and PMS2): practical aspects in antigen retrieval and biotin blocking protocols.
        Appl. Immunohistochem. Mol. Morphol. : Appl. Immunohistochem. Mol. Morphol. AIMM. 2003; 11 (Mar): 73-77
        • Liu M.
        • Yu Y.
        • Jiang H.
        • Zhang L.
        • Zhang P.P.
        • Yu P.
        • et al.
        Simvastatin suppresses vascular inflammation and atherosclerosis in ApoE(-/-) mice by downregulating the HMGB1- 25 RAGE axis.
        Acta Pharmacol. Sin. 2013; 34 (Jun): 830-836
        • Helps S.C.
        • Thornton E.
        • Kleinig T.J.
        • Manavis J.
        • Vink R.
        Automatic nonsubjective estimation of antigen content visualized by immunohistochemistry using color deconvolution.
        Appl. Immunohistochem. Mol. Morphol. : AIMM. 2012; 20 (Jan): 82-90
        • Nunnari J.J.
        • Zand T.
        • Joris I.
        • Majno G.
        Quantitation of oil red O staining of the aorta in hypercholesterolemic rats.
        Exp. Mol. Pathol. 1989; 51 (Aug): 1-7
        • Kromhout D.
        • Giltay E.J.
        • Geleijnse J.M.
        n-3 fatty acids and cardiovascular events after myocardial infarction.
        N. Engl. J. Med. 2010; 363 (Nov 18): 2015-2026
        • Rauch B.
        • Schiele R.
        • Schneider S.
        • Diller F.
        • Victor N.
        • Gohlke H.
        • et al.
        OMEGA, a randomized, placebo-controlled trial to test the effect of highly purified omega-3 fatty acids on top of modern guideline-adjusted therapy after myocardial infarction.
        Circulation. 2010; 122 (Nov 23): 2152-2159
        • Bosch J.
        • Gerstein H.C.
        • Dagenais G.R.
        • Diaz R.
        • Dyal L.
        • Jung H.
        • et al.
        n-3 fatty acids and cardiovascular outcomes in patients with dysglycemia.
        N. Engl. J. Med. 2012; 367 (Jul 26): 309-318
        • Bowman L.
        • Mafham M.
        • Wallendszus K.
        • Stevens W.
        • Buck G.
        • Barton J.
        • et al.
        Effects of n-3 fatty acid supplements in diabetes mellitus.
        N. Engl. J. Med. 2018; 379 (Oct 18): 1540-1550
        • Manson J.E.
        • Cook N.R.
        • Lee I.M.
        • Christen W.
        • Bassuk S.S.
        • Mora S.
        • et al.
        Marine n-3 fatty acids and prevention of cardiovascular disease and cancer.
        N. Engl. J. Med. 2019; 380 (Jan 3): 23-32
        • Hayashi K.
        • Murai T.
        • Oikawa H.
        • Masuda T.
        • Kimura K.
        • Muehlich S.
        • et al.
        A novel inhibitory mechanism of MRTF-A/B on the ICAM-1 gene expression in vascular endothelial cells.
        Sci. Rep. 2015; 5 (May 29): 10627
        • Gidlof O.
        • Sathanoori R.
        • Magistri M.
        • Faghihi M.A.
        • Wahlestedt C.
        • Olde B.
        • et al.
        Extracellular uridine triphosphate and adenosine triphosphate attenuate endothelial inflammation through miR-22-mediated ICAM-1 inhibition.
        J. Vasc. Res. 2015; 52: 71-80
        • Moore K.J.
        • Sheedy F.J.
        • Fisher E.A.
        Macrophages in atherosclerosis: a dynamic balance.
        Nat. Rev. Immunol. 2013; 13 (Oct): 709-721
        • Guo X.F.
        • Sinclair A.J.
        • Kaur G.
        • Li D.
        Differential effects of EPA, DPA and DHA on cardio-metabolic risk factors in high-fat diet fed mice.
        Prostaglandins Leukot. Essent. Fatty Acids. 2018 Sep; 136: 47-55
        • Allaire J.
        • Couture P.
        • Leclerc M.
        • Charest A.
        • Marin J.
        • Lepine M.C.
        • et al.
        A randomized, crossover, head-to-head comparison of eicosapentaenoic acid and docosahexaenoic acid supplementation to reduce inflammation markers in men and women: the Comparing EPA to DHA (ComparED) Study.
        Am. J. Clin. Nutr. 2016; 104 (Aug): 280-287
        • Mori T.A.
        • Burke V.
        • Puddey I.B.
        • Watts G.F.
        • O'Neal D.N.
        • Best J.D.
        • et al.
        Purified eicosapentaenoic and docosahexaenoic acids have differential effects on serum lipids and lipoproteins, LDL particle size, glucose, and insulin in mildly hyperlipidemic men.
        Am. J. Clin. Nutr. 2000; 71 (May): 1085-1094
        • Woodman R.J.
        • Mori T.A.
        • Burke V.
        • Puddey I.B.
        • Watts G.F.
        • Beilin L.J.
        Effects of purified eicosapentaenoic and docosahexaenoic acids on glycemic control, blood pressure, and serum lipids in type 2 diabetic patients with treated hypertension.
        Am. J. Clin. Nutr. 2002; 76 (Nov): 1007-1015
        • Park Y.
        • Harris W.S.
        Omega-3 fatty acid supplementation accelerates chylomicron triglyceride clearance.
        J. Lipid Res. 2003; 44 (Mar): 455-463
        • Harris W.S.
        • Miller M.
        • Tighe A.P.
        • Davidson M.H.
        • Schaefer E.J.
        Omega-3 fatty acids and coronary heart disease risk: clinical and mechanistic perspectives.
        Atherosclerosis. 2008; 197 (Mar): 12-24
        • Tillander V.
        • Bjorndal B.
        • Burri L.
        • Bohov P.
        • Skorve J.
        • Berge R.K.
        • et al.
        Fish oil and krill oil supplementations differentially regulate lipid catabolic and synthetic pathways in mice.
        Nutr. Metab. 2014; 11: 20
        • Rekhter M.D.
        • Zhang K.
        • Narayanan A.S.
        • Phan S.
        • Schork M.A.
        • Gordon D.
        Type I collagen gene expression in human atherosclerosis. Localization to specific plaque regions.
        Am. J. Pathol. 1993; 143 (Dec): 1634-1648
        • Libby P.
        • Geng Y.J.
        • Aikawa M.
        • Schoenbeck U.
        • Mach F.
        • Clinton S.K.
        • et al.
        Macrophages and atherosclerotic plaque stability.
        Curr. Opin. Lipidol. 1996; 7 (Oct): 330-335
        • Hegyi L.
        • Hardwick S.J.
        • Siow R.C.
        • Skepper J.N.
        Macrophage death and the role of apoptosis in human atherosclerosis.
        J. Hematother. Stem Cell Res. 2001; 10 (Feb): 27-42
        • Cawood A.L.
        • Ding R.
        • Napper F.L.
        • Young R.H.
        • Williams J.A.
        • Ward M.J.
        • et al.
        Eicosapentaenoic acid (EPA) from highly concentrated n-3 fatty acid ethyl esters is incorporated into advanced atherosclerotic plaques and higher plaque EPA is associated with decreased plaque inflammation and increased stability.
        Atherosclerosis. 2010; 212 (Sep): 252-259
        • Kannel W.B.
        • Dawber T.R.
        • Kagan A.
        • Revotskie N.
        • Stokes 3rd, J.
        Factors of risk in the development of coronary heart disease--six year follow-up experience. The Framingham Study.
        Ann. Intern. Med. 1961; 55 (Jul): 33-50
        • Stamler J.
        • Wentworth D.
        • Neaton J.D.
        Is relationship between serum cholesterol and risk of premature death from coronary heart disease continuous and graded? Findings in 356,222 primary screenees of the Multiple Risk Factor Intervention Trial (MRFIT).
        Jama. 1986; 256 (Nov 28): 2823-2828
        • Honda S.
        • Sidharta S.L.
        • Shishikura D.
        • Takata K.
        • Di Giovanni G.A.
        • Nguyen T.
        • et al.
        High-density lipoprotein cholesterol associated with change in coronary plaque lipid burden assessed by near infrared spectroscopy.
        Atherosclerosis. 2017; 265 (Oct): 110-116
        • Waxman S.
        • Dixon S.R.
        • L'Allier P.
        • Moses J.W.
        • Petersen J.L.
        • Cutlip D.
        • et al.
        In vivo validation of a catheter-based near-infrared spectroscopy system for detection of lipid core coronary plaques: initial results of the SPECTACL study.
        JACC Cardiovascular imaging. 2009; 2 (Jul): 858-868
        • Gardner C.M.
        • Tan H.
        • Hull E.L.
        • Lisauskas J.B.
        • Sum S.T.
        • Meese T.M.
        • et al.
        Detection of lipid core coronary plaques in autopsy specimens with a novel catheter-based near- infrared spectroscopy system.
        JACC Cardiovascular imaging. 2008; 1 (Sep): 638-648
        • Kang S.J.
        • Mintz G.S.
        • Pu J.
        • Sum S.T.
        • Madden S.P.
        • Burke A.P.
        • et al.
        Combined IVUS and NIRS detection of fibroatheromas: histopathological validation in human coronary arteries.
        JACC Cardiovascular imaging. 2015; 8 (Feb): 184-194
        • Paramel Varghese G.
        • Folkersen L.
        • Strawbridge R.J.
        • Halvorsen B.
        • Yndestad A.
        • Ranheim T.
        • et al.
        NLRP3 inflammasome expression and activation in human atherosclerosis.
        J. Am. Heart Assoc. 2016; 5 (May 20)
        • Martinez-Micaelo N.
        • Gonzalez-Abuin N.
        • Pinent M.
        • Ardevol A.
        • Blay M.
        Dietary fatty acid composition is sensed by the NLRP3 inflammasome: omega-3 fatty acid (DHA) prevents NLRP3 activation in human macrophages.
        Food Funct. 2016; 7 (Aug 10): 3480-3487
        • Shen L.
        • Yang Y.
        • Ou T.
        • Key C.C.
        • Tong S.H.
        • Sequeira R.C.
        • et al.
        Dietary PUFAs attenuate NLRP3 inflammasome activation via enhancing macrophage autophagy.
        J. Lipid Res. 2017; 58 (Sep): 1808-1821
        • Sadeghi S.
        • Wallace F.A.
        • Calder P.C.
        Dietary lipids modify the cytokine response to bacterial lipopolysaccharide in mice.
        Immunology. 1999; 96 (Mar): 404-410
        • Kolahi S.
        • Ghorbanihaghjo A.
        • Alizadeh S.
        • Rashtchizadeh N.
        • Argani H.
        • Khabazzi A.R.
        • et al.
        Fish oil supplementation decreases serum soluble receptor activator of nuclear factor-kappa B ligand/osteoprotegerin ratio in female patients with rheumatoid arthritis.
        Clin. Biochem. 2010; 43 (Apr): 576-580
        • Shimizu T.
        • Iwamoto T.
        • Itou S.
        • Iwata N.
        • Endo T.
        • Takasaki M.
        Effect of ethyl icosapentaenoate (EPA) on the concentration of tumor necrosis factor (TNF) and interleukin-1 (IL-1) in the carotid artery of cuff-sheathed rabbit models.
        J. Atherosclerosis Thromb. 2001; 8: 45-49
        • Vassiliou E.K.
        • Kesler O.M.
        • Tadros J.H.
        • Ganea D.
        Bone marrow-derived dendritic cells generated in the presence of resolvin E1 induce apoptosis of activated CD4+ T cells.
        J. Immunol. 2008; 181 (Oct 1): 4534-4544