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Pinilla-González V, Rojas-Solé C, Gómez-Hevia F, González-Fernández T, Cereceda-Cornejo A, Chichiarelli S, Saso L, Rodrigo R. Tapping into Nature's Arsenal: Harnessing the Potential of Natural Antioxidants for Human Health and Disease Prevention. Foods 2024; 13:1999. [PMID: 38998505 PMCID: PMC11241326 DOI: 10.3390/foods13131999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 06/22/2024] [Accepted: 06/22/2024] [Indexed: 07/14/2024] Open
Abstract
Numerous natural antioxidants commonly found in our daily diet have demonstrated significant benefits for human health and various diseases by counteracting the impact of reactive oxygen and nitrogen species. Their chemical properties enable a range of biological actions, including antihypertensive, antimicrobial, anti-inflammatory, anti-fibrotic, and anticancer effects. Despite promising outcomes from preclinical studies, ongoing debate persists regarding their reproducibility in human clinical models. This controversy largely stems from a lack of understanding of the pharmacokinetic properties of these compounds, coupled with the predominant focus on monotherapies in research, neglecting potential synergistic effects arising from combining different antioxidants. This study aims to provide an updated overview of natural antioxidants, operating under the hypothesis that a multitherapeutic approach surpasses monotherapy in efficacy. Additionally, this study underscores the importance of integrating these antioxidants into the daily diet, as they have the potential to prevent the onset and progression of various diseases. To reinforce this perspective, clinical findings pertaining to the treatment and prevention of non-alcoholic fatty liver disease and conditions associated with ischemia and reperfusion phenomena, including myocardial infarction, postoperative atrial fibrillation, and stroke, are presented as key references.
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Affiliation(s)
- Víctor Pinilla-González
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380000, Chile; (V.P.-G.); (C.R.-S.); (F.G.-H.); (T.G.-F.); (A.C.-C.)
| | - Catalina Rojas-Solé
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380000, Chile; (V.P.-G.); (C.R.-S.); (F.G.-H.); (T.G.-F.); (A.C.-C.)
| | - Francisca Gómez-Hevia
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380000, Chile; (V.P.-G.); (C.R.-S.); (F.G.-H.); (T.G.-F.); (A.C.-C.)
| | - Tommy González-Fernández
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380000, Chile; (V.P.-G.); (C.R.-S.); (F.G.-H.); (T.G.-F.); (A.C.-C.)
| | - Antonia Cereceda-Cornejo
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380000, Chile; (V.P.-G.); (C.R.-S.); (F.G.-H.); (T.G.-F.); (A.C.-C.)
| | - Silvia Chichiarelli
- Department of Biochemical Sciences “A. Rossi-Fanelli”, Sapienza University of Rome, 00185 Rome, Italy;
| | - Luciano Saso
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Faculty of Pharmacy and Medicine Sapienza University, P.le Aldo Moro 5, 00185 Rome, Italy;
| | - Ramón Rodrigo
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380000, Chile; (V.P.-G.); (C.R.-S.); (F.G.-H.); (T.G.-F.); (A.C.-C.)
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Abstract
The lipid landscapes of cellular membranes are complex and dynamic, are tissue dependent, and can change with the age and the development of a variety of diseases. Researchers are now gaining new appreciation for the regulation of ion channel proteins by the membrane lipids in which they are embedded. Thus, as membrane lipids change, for example, during the development of disease, it is likely that the ionic currents that conduct through the ion channels embedded in these membranes will also be altered. This chapter provides an overview of the complex regulation of prokaryotic and eukaryotic voltage-dependent sodium (Nav) channels by fatty acids, sterols, glycerophospholipids, sphingolipids, and cannabinoids. The impact of lipid regulation on channel gating kinetics, voltage-dependence, trafficking, toxin binding, and structure are explored for Nav channels that have been examined in heterologous expression systems, native tissue, and reconstituted into artificial membranes. Putative mechanisms for Nav regulation by lipids are also discussed.
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Affiliation(s)
- N D'Avanzo
- Université de Montréal, Montréal, QC, Canada.
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Rodrigo R, Cereceda M, Castillo R, Asenjo R, Zamorano J, Araya J, Castillo-Koch R, Espinoza J, Larraín E. Prevention of atrial fibrillation following cardiac surgery: basis for a novel therapeutic strategy based on non-hypoxic myocardial preconditioning. Pharmacol Ther 2008; 118:104-27. [PMID: 18346791 DOI: 10.1016/j.pharmthera.2008.01.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Accepted: 01/24/2008] [Indexed: 02/06/2023]
Abstract
Atrial fibrillation is the most common complication of cardiac surgical procedures performed with cardiopulmonary bypass. It contributes to increased hospital length of stay and treatment costs. At present, preventive strategies offer only suboptimal benefits, despite improvements in anesthesia, surgical technique, and medical therapy. The pathogenesis of postoperative atrial fibrillation is considered to be multifactorial. However oxidative stress is a major contributory factor representing the unavoidable consequences of ischemia/reperfusion cycle occurring in this setting. Considerable evidence suggests the involvement of reactive oxygen species (ROS) in the pathogenic mechanism of this arrhythmia. Interestingly, the deleterious consequences of high ROS exposure, such as inflammation, cell death (apoptosis/necrosis) or fibrosis, may be abrogated by a myocardial preconditioning process caused by previous exposure to moderate ROS concentration known to trigger survival response mechanisms. The latter condition may be created by n-3 PUFA supplementation that could give rise to an adaptive response characterized by increased expression of myocardial antioxidant enzymes and/or anti-apoptotic pathways. In addition, a further reinforcement of myocardial antioxidant defenses could be obtained through vitamins C and E supplementation, an intervention also known to diminish enzymatic ROS production. Based on this paradigm, this review presents clinical and experimental evidence supporting the pathophysiological and molecular basis for a novel therapeutic approach aimed to diminish the incidence of postoperative atrial fibrillation through a non-hypoxic preconditioning plus a reinforcement of the antioxidant defense system in the myocardial tissue.
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Affiliation(s)
- Ramón Rodrigo
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile.
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McLennan PL, Abeywardena MY. Membrane basis for fish oil effects on the heart: linking natural hibernators to prevention of human sudden cardiac death. J Membr Biol 2006; 206:85-102. [PMID: 16456720 DOI: 10.1007/s00232-005-0787-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Indexed: 11/29/2022]
Abstract
The concept that diet-induced changes in membrane lipids could modify heart function partly arose from observations that membrane composition and physical properties were closely associated with the capacity of the heart to respond appropriately to torpor and hibernation. Observations of natural hibernators further revealed that behavior of key membrane-bound enzymes could be influenced through the lipid composition of the cell membrane, either by changing the surrounding fatty acids through reconstitution into a foreign lipid milieu of different composition, or by alteration through diet. Myocardial responsiveness to beta-adrenoceptor stimulation, including initiation of spontaneous dysrhythmic contractions, was altered by both hibernation and dietary modulation of membrane fatty acids, suggesting modified vulnerability to cardiac arrhythmia. Subsequent studies using whole-animal models recognized that vulnerability to ventricular fibrillation decreased as the polyunsaturated: saturated fat (P:S) ratio of the diet increased. However, dietary fish oils, which typically contain at least 30% saturated fatty acids and only 30% long-chain n-3 (omega-3) polyunsaturated fatty acids (PUFA), exhibit antiarrhythmic effects that exceed the predicted influence of the P:S ratio, suggesting properties unique to the long-chain n-3 PUFA. Large-scale clinical trials and epidemiology have confirmed the arrhythmia prevention observed in vitro in myocytes, papillary muscles, and isolated hearts and in whole-animal models of sudden cardiac death. Some progress has been made towards a biologically plausible mechanism. These developments highlight nature's ability to provide guidance for the most unexpected applications.
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Affiliation(s)
- P L McLennan
- Smart Foods Centre, Department of Biomedical Science, University of Wollongong, NSW 2522, Australia.
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Venardos K, Harrison G, Headrick J, Perkins A. Effects of dietary selenium on glutathione peroxidase and thioredoxin reductase activity and recovery from cardiac ischemia-reperfusion. J Trace Elem Med Biol 2004; 18:81-8. [PMID: 15487768 DOI: 10.1016/j.jtemb.2004.01.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Glutathione peroxidase and thioredoxin reductase are selenocysteine-dependent enzymes that protect against oxidative injury. This study examined the effects of dietary selenium on the activity of these two enzymes in rats, and investigated the ability of selenium to modulate myocardial function post ischemia-reperfusion. Male wistar rats were fed diets containing 0, 50, 240 and 1000 microg/kg sodium selenite for 5 weeks. Langendorff perfused hearts isolated from these rats were subjected to 22.5 min global ischemia and 45 min reperfusion, with functional recovery assessed. Liver samples were collected at the time of sacrifice, and heart and liver tissues assayed for thioredoxin reductase and glutathione peroxidase activity. Selenium deficiency reduced the activity of both glutathione peroxidase and thioredoxin reductase systemically. Hearts from selenium deficient animals were more susceptible to ischemia-reperfusion injury when compared to normal controls (38% recovery of rate pressure product (RPP) vs. 47% recovery of RPP). Selenium supplementation increased the endogenous activity of thioredoxin reductase and glutathione peroxidase and resulted in improved recovery of cardiac function post ischemia reperfusion (57% recovery of RPP). Endogenous activity of glutathione peroxidase and thioredoxin reductase is dependent on an adequate supply of the micronutrient selenium. Reduced activity of these antioxidant enzymes is associated with significant reductions in myocardial function post ischemia-reperfusion.
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Affiliation(s)
- Kylie Venardos
- Heart Foundation Research Centre, School of Health Science, Griffith University Gold Coast Campus, Southpor QLD 4217, Australia
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Ewart HS, Cole LK, Kralovec J, Layton H, Curtis JM, Wright JLC, Murphy MG. Fish oil containing phytosterol esters alters blood lipid profiles and left ventricle generation of thromboxane a(2) in adult guinea pigs. J Nutr 2002; 132:1149-52. [PMID: 12042424 DOI: 10.1093/jn/132.6.1149] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This study was designed to investigate the lipid-lowering ability of a novel dietary ingredient composed of phytosterols esterified to (n-3) polyunsaturated fatty acids (PUFA) [PS(n-3)]. Adult guinea pigs were fed a test diet supplemented with PS(n-3) (25 g/kg) and corn oil (CO, 5 g/kg), whereas the diet fed to control guinea pigs was supplemented with CO only (30 g/kg). Cholesterol was added to both diets (0.8 g/kg). After 3-4 wk of consuming the diets, serum total cholesterol (TC) and triacylglycerol (TAG) in the PS(n-3) group were 36 and 29% lower, respectively, than levels in controls (P < 0.05). The lower TC levels in the PS(n-3) group reflected a 38% reduction in non-HDL cholesterol (non-HDL-C), whereas the HDL-C concentration was unaffected. Analysis of cardiac left ventricle indicated that generation of the proaggregatory, arrhythmic eicosanoid, thromboxane A(2), was >60% lower in the PS(n-3)-supplemented guinea pigs than in CO controls (P < 0.001). This study demonstrates that the TAG-lowering and eicosanoid-modifying properties of the fish oil (n-3) PUFA are retained when they are provided in the diet in ester linkage with hypocholesterolemic phytosterols.
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Affiliation(s)
- H Stephen Ewart
- Ocean Nutrition Canada, Limited, Halifax, Nova Scotia, Canada.
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Leifert WR, Dorian CL, Jahangiri A, McMurchie EJ. Dietary fish oil prevents asynchronous contractility and alters Ca(2+) handling in adult rat cardiomyocytes. J Nutr Biochem 2001; 12:365-376. [PMID: 11516641 DOI: 10.1016/s0955-2863(01)00151-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This study examined the effects of dietary incorporation of n-3 polyunsaturated fatty acids (PUFAs) into cardiac membrane phospholipids on Ca(2+) handling (using Fura-2) and arrhythmic contractility in electrically-stimulated, adult rat ventricular cardiomyocytes. Dietary lipid supplementation with fish oil (FO) for 3 weeks significantly increased the proportion of total n-3 polyunsaturated fatty acids (in particular, docosahexaenoic acid) in ventricular membrane phospholipids compared with a saturated fat (SF) supplemented diet (26.2 +/- 0.9% vs 6.9 +/- 0.9%, respectively, P < 0.001). Cardiomyocytes isolated from the FO group were significantly (P < 0.001) less susceptible to isoproterenol-induced arrhythmic contractile activity compared with the SF group over a range of isoproterenol concentrations. Isoproterenol (0.5 &mgr;M) stimulation increased end-diastolic and systolic [Ca(2+)](i) to a similar extent in both groups. The time constant of Ca(2+) transient decay was significantly increased in the FO group compared with the SF group (98.4 +/- 2.8 ms, n = 8 and 86.9 +/- 2.1 ms, n = 8, P < 0.01, respectively). The effect of dietary n-3 PUFA incorporation into membrane phospholipids was not associated with changes in sarcoplasmic reticulum Ca(2+) content (measured by rapid application of caffeine) or membrane fluidity. The increase in the time constant of decay of Ca(2+) transients following dietary supplementation with FO may indicate altered functioning of the sarcolemmal Na(+)-Ca(2+) exchanger by n-3 PUFA incorporation into membrane phospholipids.
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Affiliation(s)
- W R. Leifert
- CSIRO Health Sciences and Nutrition, 5000, Adelaide, SA, Australia
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Leifert WR, Jahangiri A, Saint DA, McMurchie EJ. Effects of dietary n-3 fatty acids on contractility, Na+ and K+ currents in a rat cardiomyocyte model of arrhythmia. J Nutr Biochem 2000; 11:382-92. [PMID: 11044633 DOI: 10.1016/s0955-2863(00)00094-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The n-3 polyunsaturated fatty acids (PUFAs) have been reported to prevent ventricular fibrillation in human clinical studies and in studies involving experimental animals and isolated cardiomyocytes. This study aimed to determine whether dietary n-3 PUFAs could prevent isoproterenol and free radical-induced arrhythmic (asynchronous) contractile activity in adult rat cardiomyocytes and whether whole-cell Na(+) and K(+) currents measured by patch-clamp techniques were affected. Dietary supplementation with fish oil for 3 weeks significantly increased the proportion of total n-3 PUFAs in ventricular membrane phospholipids compared with saturated fat supplementation (18.8 +/- 0.6% vs. 8.1 +/- 1.0%, respectively). Cardiomyocytes from the fish oil group were less susceptible to isoproterenol-induced asynchronous contractile activity than were those from the saturated fat group [EC(50) values: 892 +/- 130 nM, n = 6 and 347 +/- 91 nM, n = 6 (P < 0.05), respectively]. Fish oil supplementation also prolonged the time taken to develop asynchronous contractile activity induced by superoxide and hydrogen peroxide. The voltage dependence of inactivation of Na(+) currents were significantly altered (-73.5 +/- 1.2 mV, n = 5 vs. -76.7 +/- 0.7 mV, n = 5, P < 0.05, for saturated fat and fish oil treated groups, respectively). The voltage dependence of activation of Na(+) and K(+) currents was not significantly affected by the dietary fish oil treatment. These results demonstrate the antiarrhythmic effects of dietary fish oil in a cardiomyocyte model of arrhythmia.
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Affiliation(s)
- W R Leifert
- Department of Physiology, University of Adelaide, Adelaide, Australia
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Jahangiri A, Leifert WR, Patten GS, McMurchie EJ. Termination of asynchronous contractile activity in rat atrial myocytes by n-3 polyunsaturated fatty acids. Mol Cell Biochem 2000; 206:33-41. [PMID: 10839192 DOI: 10.1023/a:1007025007403] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A protective effect of the n-3 polyunsaturated fatty acids (PUFAs) in preventing ventricular fibrillation in experimental animals and cultured cardiomyocytes has been demonstrated in a number of studies. In this study, a possible role for the n-3 PUFAs in the treatment of atrial fibrillation (AF) was investigated at the cellular level using atrial myocytes isolated from young adult rats as the experimental model. Electrically-stimulated, synchronously-contracting myocytes were induced to contract asynchronously by the addition of 10 microM isoproterenol. Asynchronous contractile activity was reduced following acute addition of the n-3 PUFAs docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) at 10 microM, compared with no fatty acid addition (from 99.0+/-1.0% to 30.7+/-5.2% (p < 0.05) for DHA and 23.8+/-2.8% (p < 0.01) for EPA), while the saturated fatty acid, docosanoic acid (DA) and the methyl ester of DHA (DHA m.e.) did not exert a significant effect on asynchronous contractile activity. Asynchronous contractile activity was also reduced to 1.7+/-1.7% in the presence of the membrane fluidising agent, benzyl alcohol (p < 0.001 vs no fatty acid addition). Cell membrane fluidity was determined by steady state fluorescence anisotropy using the fluorescent probe, TMAP-DPH. Addition of DHA, EPA or benzyl alcohol significantly increased sarcolemmal membrane fluidity (decreased anisotropy, r(ss)) of atrial myocytes compared with no addition of fatty acid (control) (from r(ss) = 0.203+/-0.004 to 0.159+/-0.004 (p < 0.01) for DHA, 0.166+/-0.001 (p < 0.01) for EPA and 0.186+/-0.003 (p < 0.05) for benzyl alcohol, while DA and DHA m.e. were without effect. It is concluded that the n-3 PUFAs exert anti-asynchronous effects in rat atrial myocytes by a mechanism which may involve changes in membrane fluidity.
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Affiliation(s)
- A Jahangiri
- Department of Physiology, The University of Adelaide, SA, Australia
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Leifert WR, Jahangiri A, McMurchie EJ. Membrane fluidity changes are associated with the antiarrhythmic effects of docosahexaenoic acid in adult rat cardiomyocytes. J Nutr Biochem 2000; 11:38-44. [PMID: 15539341 DOI: 10.1016/s0955-2863(99)00069-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/1999] [Accepted: 10/04/1999] [Indexed: 11/26/2022]
Abstract
Previous studies using neonatal rat cardiomyocytes have reported antiarrhythmic effects of long-chain polyunsaturated fatty acids (PUFAs). In this study, we examined the effects of the n-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) on the spontaneous contractile activity and membrane fluidity of adult rat ventricular myocytes. Cardiomyocytes were induced to contract spontaneously by continuous superfusion of a solution containing the arrhythmogenic agents isoproterenol (a beta-adrenergic receptor agonist) or lysophosphatidylcholine. The percentage of cardiomyocytes displaying spontaneous contractions induced by isoproterenol when pretreated with the saturated fatty acid docosanoic acid was 48.1 +/- 7.7%; the percentage for cardiomyocytes pretreated with DHA was 7.1 +/- 2.4% (P < 0.01). DHA significantly prevented lysophosphatidylcholine-induced spontaneous contractions (17.7 +/- 6.5%) compared with treatment with the saturated fatty acid stearic acid (78.0 +/- 7.3%, P < 0.01). The membrane fluidizing agent benzyl alcohol also significantly prevented spontaneous contractions in cardiomyocytes. Membrane fluidity was determined by steady-state fluorescence anisotropy (r(ss)) using the fluorescent probe N-((4-(6-phenyl-1,3,5-hexatrienyl)phenyl)propyl) trimethyl-ammonium p-toluene-sulfonate (TMAP-DPH). DHA and benzyl alcohol dose-dependently decreased the r(ss); however, saturated fatty acids were without effect. These results suggest that the antiarrhythmic mechanisms of the n-3 PUFAs such as DHA may involve changes in membrane fluidity.
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Affiliation(s)
- W R Leifert
- Department of Physiology, The University of Adelaide, CSIRO Health Sciences and Nutrition, Australia
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Leifert WR, McMurchie EJ, Saint DA. Inhibition of cardiac sodium currents in adult rat myocytes by n-3 polyunsaturated fatty acids. J Physiol 1999; 520 Pt 3:671-9. [PMID: 10545135 PMCID: PMC2269607 DOI: 10.1111/j.1469-7793.1999.00671.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
1. The acute effects of n-3 polyunsaturated fatty acids were determined on whole-cell sodium currents recorded in isolated adult rat ventricular myocytes using patch clamp techniques. 2. The n-3 polyunsaturated fatty acids docosahexaenoic acid (22:6, n-3), eicosapentaenoic acid (20:5, n-3) and alpha-linolenic acid (18:3, n-3) dose-dependently blocked the whole-cell sodium currents evoked by a voltage step to -30 mV from a holding potential of -90 mV with EC50 values of 6.0 +/- 1.2, 16.2 +/- 1.3 and 26.6 +/- 1.3 microM, respectively. 3. Docosahexaenoic acid, eicosapentaenoic acid and alpha-linolenic acid at 25 microM shifted the voltage dependence of activation of the sodium current to more positive potentials by 9.2 +/- 2.0, 10.1 +/- 1.1 and 8.3 +/- 0.9 mV, respectively, and shifted the voltage dependence of inactivation to more negative potentials by 22.3 +/- 0.9, 17.1 +/- 3.7 and 20.5 +/- 1.0 mV, respectively. In addition, the membrane fluidising agent benzyl alcohol (10 mM) shifted the voltage dependence of activation to more positive potentials by 7.8 +/- 2.5 mV and shifted the voltage dependence of inactivation to more negative potentials (by -24.6 +/- 3.6 mV). 4. Linoleic acid (18:2, n-6), oleic acid (18:1, n-9) and stearic acid (18:0) were either ineffective or much less potent at blocking the sodium current or changing the voltage dependence of the sodium current compared with the n-3 fatty acids tested. 5. Docosahexaenoic acid, eicosapentaenoic acid, alpha-linolenic acid and benzyl alcohol significantly increased sarcolemmal membrane fluidity as measured by fluorescence anisotropy (steady-state, rss, values of 0.199 +/- 0. 004, 0.204 +/- 0.006, 0.213 +/- 0.005 and 0.214 +/- 0.009, respectively, compared with 0.239 +/- 0.002 for control), whereas stearic, oleic and linoleic acids did not alter fluidity (the rss was not significantly different from control). 6. The potency of the n-3 fatty acids docosahexaenoic acid, eicosapentaenoic acid and alpha-linolenic acid to block cardiac sodium currents is correlated with their ability to produce an increase in membrane fluidity.
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Affiliation(s)
- W R Leifert
- CSIRO Human Nutrition, Adelaide, SA 5000, Australia
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