Eicosapentaenoic Acid Treatment Research Articles

Omega-3 fatty acids protect cartilage from acute injurie by reducing the mechanical sensitivity of chondrocytes

Acute cartilage injuries, such as intra-articular fractures and blunt impacts, frequently result in chondrocyte death and extracellular matrix (ECM) degradation, significantly elevating the risk of post-traumatic osteoarthritis (PTOA). Despite advances in treatment, no effective therapies currently exist to fully cure PTOA or halt its progression. This study explores the protective effects of the dietary fatty acid eicosapentaenoic acid (EPA) on human primary chondrocytes (HPCs) and cartilage explants exposed to mechanical overload and blunt trauma. HPCs were isolated and subjected to mechanical stretching using BioFlex six-well culture plates, while cartilage explants were subjected to impact loading via a customized drop tower. EPA was incorporated into the culture medium, followed by assays to evaluate cell viability, calcium (Ca²⁺) influx, apoptosis, reactive oxygen species (ROS) levels, and collagen type II alpha (Col-2a) expression. EPA treatment markedly decreased chondrocyte mechanical sensitivity, as demonstrated by enhanced cell viability and reduced lactate dehydrogenase (LDH) release. Furthermore, EPA inhibited Piezo1 activation, leading to lower intracellular Ca²⁺ concentrations, decreased apoptosis, and diminished ROS levels. In cartilage explants, EPA improved chondrocyte viability, minimized structural damage, and sustained higher Col-2a expression compared to the blunt trauma group. These results indicate that EPA effectively shields chondrocytes and cartilage explants from mechanical overload-induced damage by inhibiting Piezo1 activation and mitigating Ca²⁺ influx, apoptosis, and oxidative stress. The findings suggest that EPA supplementation could offer a promising strategy for preventing PTOA progression following acute cartilage injuries. Further research is warranted to assess the clinical applications of EPA and confirm its efficacy in larger animal models and human trials.

Impact of fish oil supplementation on plasma levels of highly unsaturated fatty acid-containing lipid classes and molecular species in American football athletes

BackgroundPrevious studies have linked sports-related concussions and repeated subconcussive head impacts in contact sport athletes to elevated brain injury biomarkers. Docosahexaenoic acid (DHA), the primary omega-3 (n-3) highly unsaturated fatty acid (HUFA) in the brain, has shown neuroprotective effects in animal models after brain injury, but clinical research has shown mixed results.MethodsWe conducted a randomized, double-blind, placebo-controlled study on 29 Division 1 collegiate American football players, exploring the impact of DHA (2.5 g) and eicosapentaenoic acid (EPA) (1.0 g) supplied as ethyl esters, on levels of plasma lipids shown to cross the blood-brain barrier. Dietary intake data was collected using food frequency questionnaires (FFQ). Complex lipids and unesterified fatty acids were isolated from plasma, separated via reversed-phase liquid chromatography and analyzed by targeted lipidomics analysis.ResultsFFQ results indicated that participants had low dietary n-3 HUFA intake and high omega-6 (n-6):n-3 polyunsaturated fatty acids (PUFA) and HUFA ratios at baseline. After DHA + EPA supplementation, plasma lysophosphatidylcholine (LPC) containing DHA and EPA significantly increased at all timepoints (weeks 17, 21, and 26; p < 0.0001), surpassing placebo at Weeks 17 (p < 0.05) and 21 (p < 0.05). Phosphatidylcholine (PC) molecular species containing DHA or EPA, PC38:6 PC36:6, PC38:7, PC40:6, and PC40:8, increased significantly in the DHA + EPA treatment group at Weeks 17 (and 21. Plasma concentrations of non-esterified DHA and EPA rose post-supplementation in Weeks 17 and 21.ConclusionsThis study demonstrates that n-3 HUFA supplementation, in the form of ethyl esters, increased the DHA and EPA containing plasma lipid pools the have the capacity to enrich brain lipids and the potential to mitigate the effects of sports-related concussions and repeated subconcussive head impacts.Trial RegistrationAll deidentified data are available at ClinicalTrials.gov #NCT0479207.

Oral microbiota dysbiosis alters chronic restraint stress-induced depression-like behaviors by modulating host metabolism

Studies have shown that the microbiota-gut-brain axis is highly correlated with the pathogenesis of depression in humans. However, whether independent oral microbiome that do not depend on gut microbes could affect the progression of depression in human beings remains unclear, neither does the presence and underlying mechanisms of the microbiota-oral-brain axis in the development of the condition. Hence this study that encompasses clinical and animal experiments aims at investigating the correlation between oral microbiota and the onset of depression via mediating the microbiota-oral-brain axis. We compared the oral microbial compositions and metabolomes of 87 patients with depressive symptoms versus 70 healthy controls. We found that the oral microbial and metabolic signatures were significantly different between the two groups. Significantly, germ-free (GF) mice transplanted with saliva from mice exposing to chronic restraint stress (CRS) displayed depression-like behavior and oral microbial dysbiosis. This was characterized by a significant differential abundance of bacterial species, including the enrichment of Pseudomonas, Pasteurellaceae, and Muribacter, as well as the depletion of Streptococcus. Metabolomic analysis showed the alternation of metabolites in the plasma of CRS-exposed GF mice, especially Eicosapentaenoic Acid. Furthermore, oral and gut barrier dysfunction caused by CRS-induced oral microbiota dysbiosis may be associated with increased blood-brain barrier permeability. Pseudomonas aeruginosa supplementation exacerbated depression-like behavior, while Eicosapentaenoic Acid treatment conferred protection against depression-like states in mice. These results suggest that oral microbiome and metabolic function dysbiosis may be relevant to the pathogenesis and pathophysiology of depression. The proposed microbiota-oral-brain axis provides a new way and targets for us to study the pathogenesis of depression.

Eicosapentaenoic Acid Alleviates Inflammatory Response and Insulin Resistance in Pregnant Mice With Gestational Diabetes Mellitus.

This study investigated the effect of eicosapentaenoic acid (EPA) on insulin resistance in pregnant mice with gestational diabetes mellitus (GDM) and underlying mechanism. C57BL/6 mice fed with a high-fat diet for 4 weeks and the newly gestated were selected and injected with streptozotocin for GDM modeling. We demonstrated that the fasting insulin levels (FINS) and insulin sensitivity index (ISI) in serum and blood glucose level were significantly higher in GDM group than in normal control (NC) group. The low or high dose of EPA intervention reduced these levels, and the effect of high dose intervention was more significant. The area under the curve in GDM group was higher than that of NC group, and then gradually decreased after low or high dose of EPA treatment. The serum levels of TC, TG and LDL were increased in GDM group, while decreased in EPA group. GDM induced down-regulation of HDL level, and the low or high dose of EPA gradually increased this level. The levels of p-AKT2Ser, p-IRS-1Tyr, GLUT4, and ratios of pIRS-1Tyr/IRS-1 and pAKT2Ser/AKT2 in gastrocnemius muscle were reduced in GDM group, while low or high dose of EPA progressively increased these alterations. GDM enhanced TLR4, NF-kappaB p65, IL-1beta, IL-6 and TNF-alpha levels in placental tissues, and these expressions were declined at different dose of EPA, and the decrease was greater at high dose. We concluded that EPA receded the release of inflammatory factors in the placental tissues by inhibiting the activation of TLR4 signaling, thereby alleviating the IR.

Omega-3 fatty acids for inflamed depression – A match/mismatch study

Despite decades of research on the pathophysiology of depression, the development of new therapeutic interventions has been slow, and no biomarkers of treatment response have been clinically implemented. Several lines of evidence suggest that the clinical and biological heterogeneity among patients with major depressive disorder (MDD) has hampered progress in this field. MDD with low-grade inflammation – “inflamed depression” – is a subtype of depression that may be associated with a superior antidepressant treatment response to anti-inflammatory compounds. Omega-3 fatty acid eicosapentaenoic acid (EPA) has anti-inflammatory properties, and preliminary data suggest that it may be particularly efficacious in inflamed depression. In this study we tested the hypothesis that add-on EPA has greater antidepressant efficacy in MDD patients with high baseline high-sensitivity C-reactive protein (hs-CRP) compared to MDD patients with low hs-CRP. All subjects received 2.2 g EPA, 400 mg docosahexaenoic acid and 800 mg of other fatty acids daily for 8 weeks, added to stable ongoing antidepressant treatment. The primary outcome was change in the 17-item Hamilton Depression Rating Scale (HAMD-17). Patients and raters were blind to baseline hs-CRP status. In an intention-to-treat analysis including all subjects with at least one post baseline visit (n = 101), ahs-CRPcut-off of ≥1 mg/L, but not ≥3 mg/L, was associated with a greater improvement in HAMD-17 total score. In addition to a general antidepressant effect among patients with hs-CRP ≥ 1 mg/L, adjuvant EPA treatment improved symptoms putatively related to inflamed depression such as fatigue and sleep difficulties. This adds to the mounting evidence that delineation of MDD subgroups based on inflammation may be clinically relevant to predict treatment response to anti-inflammatory interventions.

Eicosapentaenoic acid enhances the sensitivity of osteosarcoma to cisplatin by inducing ferroptosis through the DNA-PKcs/AKT/NRF2 pathway and reducing PD-L1 expression to attenuate immune evasion

Acquired drug resistance poses a significant challenge in osteosarcoma therapy. Therefore, it is necessary for us to discover and develop an alternative anti-cancer strategy. Previous studies have shown that eicosapentaenoic acid (EPA) significantly increases chemosensitivity in cancer cells. In this study, we discovered that EPA enhances the sensitivity of osteosarcoma to cisplatin (DDP). Interestingly, in addition to inhibiting growth and inducing apoptosis, EPA also enhances DDP-induced ferroptosis. Western blot analysis confirmed that EPA treatment significantly decreases the expression of DNA-dependent protein kinase catalytic subunit (DNA-PKcs), p-AKT, nuclear factor erythroid 2-related factor 2 (NRF2), and glutathione peroxidase 4 (GPX4) in cells. Knockdown of DNA-PKcs by siRNA further enhances the level of ferroptosis induced by EPA. Importantly, EPA can reverse the high expression level of programmed death ligand 1 (PD-L1) induced by DDP. ELISA and western blotting analysis revealed that EPA treatment decreases the levels of IL-6 and p-STAT3, which are increased by DDP treatment. Furthermore, a co-immunoprecipitation (co-IP) assay confirmed the interaction between DNA-PKcs and PD-L1, and knockdown of DNA-PKcs further reduces the expression of PD-L1. This data provides the first evidence that EPA suppresses the DNA-PKcs/AKT/NRF2/GPX4 pathway to enhance ferroptosis, and inhibits IL-6/STAT3 and DNA-PKcs to decrease PD-L1 expression, thereby sensitizing osteosarcoma to DDP. The combination of EPA and DDP presents an encouraging and promising anti-tumor strategy.

Randomised, placebo-controlled, phase 3 trial of the effect of the omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) on colorectal cancer recurrence and survival after surgery for resectable liver metastases: EPA for Metastasis Trial 2 (EMT2) study protocol

IntroductionThere remains an unmet need for safe and cost-effective adjunctive treatment of advanced colorectal cancer (CRC). The omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) is safe, well-tolerated and has anti-inflammatory...

The effect of aspirin and eicosapentaenoic acid on urinary biomarkers of prostaglandin E2 synthesis and platelet activation in participants of the seAFOod polyp prevention trial.

Urinary prostaglandin (PG) E metabolite (PGE-M) and 11-dehydro (d)-thromboxane (TX) B2 are biomarkers of cyclooxygenase-dependent prostanoid synthesis. We investigated (1) the effect of aspirin 300 mg daily and eicosapentaenoic acid (EPA) 2000 mg daily, alone and in combination, on urinary biomarker levels and, (2) whether urinary biomarker levels predicted colorectal polyp risk, during participation in the seAFOod polyp prevention trial. Urinary PGE-M and 11-d-TXB2 were measured by liquid chromatography-tandem mass spectrometry. The relationship between urinary biomarker levels and colorectal polyp outcomes was investigated using negative binomial (polyp number) and logistic (% with one or more polyps) regression models. Despite wide temporal variability in PGE-M and 11-d-TXB2 levels within individuals, both aspirin and, to a lesser extent, EPA decreased levels of both biomarkers (74% [P ≤ .001] and 8% [P ≤ .05] reduction in median 11-d-TXB2 values, respectively). In the placebo group, a high (quartile [Q] 2-4) baseline 11-d-TXB2 level predicted increased polyp number (incidence rate ratio [IRR] [95% CI] 2.26 [1.11,4.58]) and risk (odds ratio [95% CI] 3.56 [1.09,11.63]). A low (Q1) on-treatment 11-d-TXB2 level predicted reduced colorectal polyp number compared to placebo (IRR 0.34 [0.12,0.93] for combination aspirin and EPA treatment) compared to high on-treatment 11-d-TXB2 values (0.61 [0.34,1.11]). Aspirin and EPA both inhibit PGE-M and 11-d-TXB2 synthesis in keeping with shared in vivo cyclooxygenase inhibition. Colorectal polyp risk and treatment response prediction by 11-d-TXB2 is consistent with a role for platelet activation during early colorectal carcinogenesis. The use of urinary 11-d-TXB2 measurement for a precision approach to colorectal cancer risk prediction and chemoprevention requires prospective evaluation.

Eicosapentaenoic acid (EPA) reduced expression of neutrophil activation proteins in endothelial cells during challenge with angiotensin II (Ang II) and cytokines

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Amarin Pharmaceutical, Inc. Elucida Research LLC. Background Neutrophil degranulation contributes to atherogenesis and tissue injury in response to cytokine release and activation of the renin-angiotensin system (RAS), along with its effector angiotensin II (Ang II). Mixed omega-3 fatty acid (n3-FA) formulations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have not shown reduction in CV events compared to EPA-only formulations (REDUCE-IT), but the mechanisms of atheroprotection with EPA are not well understood. Purpose We measured the effects of EPA on expression of proteins related to neutrophil activation in vascular endothelial cells (ECs) under various inflammatory challenges, specifically exposure to Ang II and the cytokine IL-6 in vitro. Methods Human umbilical vein ECs (HUVECs) were challenged with the cytokine IL-6 at (12 ng/mL) and Ang II (100 nM) for 2 h, then treated with EPA (40 µM) for 24 h. Global proteomic analysis was performed using LC/MS to measure relative expression levels of over 2,500 proteins simultaneously. Only significant (p&amp;lt;0.05) changes in expression between treatment groups &amp;gt;1-fold (100%) were analyzed by differential enrichment analysis of proteomics data (DEP) and included in gene set enrichment analyses (GSEA). Results EPA significantly down/up-regulated expression of 507/505 and 544/472 proteins, respectively, compared with Ang II and IL-6 alone. The GSEA revealed EPA treatment significantly modulated expression of 88 and 80 proteins within the neutrophil degranulation pathway (Gene Ontology ID: 0043312), compared to Ang II and IL-6, respectively. Of these proteins, 20 were similarly modulated by EPA relative to each stimulus (13 decreased, 7 increased expression). This included a 110% decrease in expression of heat shock protein 90 (110%) and HSP 86 (110%) and a 140% and 110% increase in junction plakoglobin relative to Ang II and IL-6, respectively, which is also involved in endothelial cell-cell adhesion. Conclusion EPA modulated expression of multiple proteins linked to neutrophil degranulation following challenge with either Ang II or IL-6. The effects of EPA on neutrophil protein expression may lead to reduced inflammation and risk for patients with CV disease as demonstrated in outcome trials.

Eicosapentaenoic acid (EPA) reduces pulmonary endothelial dysfunction and inflammation due to changes in protein expression during exposure to particulate matter air pollution

AimsInhalation 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 resultsWe 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). ConclusionThese cellular changes may contribute to anti-inflammatory, cytoprotective and lipid changes associated with EPA treatment during air pollution exposure.

MiR-29a-3p promotes the regulatory role of eicosapentaenoic acid in the NLRP3 inflammasome and autophagy in microglial cells.

Eicosapentaenoic acid (EPA) has been reported to play an anti-inflammatory and antioxidative stress role in a series of human diseases, including major depressive disorder. However, its exact mechanism is still largely unknown. Mouse BV-2 cells were treated with lipopolysaccharide (LPS) to induce an in vitro inflammatory cell model of depression. Cytotoxic effects were assessed with MTT and lactate dehydrigebase release assays. Cytokine mediators were elevated by western blot and enzyme-linked immunosorbent assays. Autophagy-relators were determined by immunofluorescence and western blot analyses. Interaction relationships among molecules were evaluated utilizing chromatin immunoprecipitation and dual luciferase assays. Methylated miR-29a-3p was detected via methylation-specific polymerase chain reaction. EPA treatment at 60 μM had no cytotoxic effects on BV2 cells and significantly inhibited the LPS-induced inflammatory response and NLRP3 inflammasome but activated autophagy, while all these effects were reversed by the autophagy inhibitor 3-MA. Importantly, miR-29a-3p exhibited a role similar to that of EPA in LPS-treated BV2 cells. Mechanistically, EPA treatment elevated miR-29a-3p by repressing its promoter methylation. MAPK8 was a direct target of miR-29a-3p. Inhibition of miR-29a-3p greatly diminished the regulatory roles mediated by EPA in LPS-treated BV2 cells, while these roles were further impeded after MAPK8 silencing. To conclude, our data demonstrated that EPA treatment alleviated LPS-induced NLRP3 inflammasomes by activating autophagy via regulation of miR-29a-3p/MAPK8 signaling, which further elucidates the potential antidepressant mechanism of EPA.

Plasma and rectal mucosal oxylipin levels during aspirin and eicosapentaenoic acid treatment in the seAFOod polyp prevention trial

BackgroundAspirin and eicosapentaenoic acid (EPA) have colorectal polyp prevention activity, alone and in combination. This study measured levels of plasma and rectal mucosal oxylipins in participants of the seAFOod 2 × 2 factorial, randomised, placebo-controlled trial, who received aspirin 300 mg daily and EPA 2000 mg free fatty acid, alone and in combination, for 12 months. MethodsResolvin (Rv) E1, 15-epi-lipoxin (LX) A4 and respective precursors 18-HEPE and 15-HETE (with chiral separation) were measured by ultra-high performance liquid chromatography-tandem mass spectrometry in plasma taken at baseline, 6 months and 12 months, as well as rectal mucosa obtained at trial exit colonoscopy at 12 months, in 401 trial participants. ResultsDespite detection of S- and R- enantiomers of 18-HEPE and 15-HETE in ng/ml concentrations, RvE1 or 15‑epi-LXA4 were not detected above a limit of detection of 20 pg/ml in plasma or rectal mucosa, even in individuals randomised to both aspirin and EPA. We have confirmed in a large clinical trial cohort that prolonged (12 months) treatment with EPA is associated with increased plasma 18-HEPE concentrations (median [inter-quartile range] total 18-HEPE 0.51 [0.21–1.95] ng/ml at baseline versus 0.95 [0.46–4.06] ng/ml at 6 months [P<0.0001] in those randomised to EPA alone), which correlate strongly with respective rectal mucosal 18-HEPE levels (r = 0.82; P<0.001), but which do not predict polyp prevention efficacy by EPA or aspirin. ConclusionAnalysis of seAFOod trial plasma and rectal mucosal samples has not provided evidence of synthesis of the EPA-derived specialised pro-resolving mediator RvE1 or aspirin-trigged lipoxin 15‑epi-LXA4. We cannot rule out degradation of individual oxylipins during sample collection and storage but readily measurable precursor oxylipins argues against widespread degradation.

Eicosapentaenoic Acid Preserves Mitochondrial Quality and Attenuates Cardiac Remodeling After Myocardial Infarction in Rats.

Eicosapentaenoic acid (EPA) reduces the risk of ischemic heart diseases and is a component of mitochondria. We herein investigated whether dietary EPA mediated mitochondrial fatty acid compositions, dynamics, and functions, resulting in the attenuation of cardiac remodeling after myocardial infarction (MI). The coronary artery of male rats was ligated to induce MI, and they were then treated with or without EPA (1000mg/kg/day) for 12weeks. The EPA treatment improved left ventricular systolic function and increased the mitochondrial content of EPA in the non-infarct region 12weeks after MI. The content of ATP and mitochondrial complex II, III, and IV activities decreased after MI but were maintained by the EPA treatment in association with the preservation of optic atrophy 1, a mitochondrial fusion protein. The present results suggest that dietary EPA increased the mitochondrial content of EPA and preserved the expression of mitochondrial fusion proteins and energy metabolism, which attenuated left ventricular remodeling after MI.

The Protective Effects of Eicosapentaenoic Acid for Stress-induced Accelerated Senescence in Vascular Endothelial Cells.

Background: Eicosapentaenoic acid (EPA) is an omega-3 fatty acid that protects against cardiovascular diseases in patients with hypertriglyceridemia and may have pleotropic effects beyond lowering triglycerides. Many degenerative diseases, such as atherosclerosis and diabetes, are related to cellular senescence as a pathophysiological mechanism. We aimed to examine whether EPA could protect vascular endothelial cells under stress conditions against stress-induced accelerated senescence (SIAS). Methods: Cultured human umbilical vein endothelial cells (HUVECs) were exposed to H2O2 as oxidative stress and a high glucose concentration with palmitate as a glucolipotoxic condition. Changes in cell viability, apoptosis, lactate dehydrogenase release, and cell cycle analysis were measured by cell counting kit-8 assay, annexin V/ propidium iodide staining, and enzyme-linked immunosorbent assay, respectively. EPA was applied in stress conditions. The degree of senescence was measured by senescence-associated beta-galactosidase staining and p16 staining using immunofluorescence. Apoptosis and cellular senescence-related proteins were measured by Western blotting. Results: Cultured HUVECs under oxidative and glucolipotoxic stresses revealed accelerated senescence and increased apoptosis. These changes were markedly reversed by EPA administration, and the expressions of apoptosis and cellular senescence-related proteins were reversed by EPA treatment. Conclusion: EPA effectively protects HUVECs against SIAS, which may be one of its pleotrophic effects.

Energy metabolism in skeletal muscle cells from donors with different body mass index.

Obesity and physical inactivity have a profound impact on skeletal muscle metabolism. In the present work, we have investigated differences in protein expression and energy metabolism in primary human skeletal muscle cells established from lean donors (BMI<25kg/m2) and individuals with obesity (BMI>30kg/m2). Furthermore, we have studied the effect of fatty acid pretreatment on energy metabolism in myotubes from these donor groups. Alterations in protein expression were investigated using proteomic analysis, and energy metabolism was studied using radiolabeled substrates. Gene Ontology enrichment analysis showed that glycolytic, apoptotic, and hypoxia pathways were upregulated, whereas the pentose phosphate pathway was downregulated in myotubes from donors with obesity compared to myotubes from lean donors. Moreover, fatty acid, glucose, and amino acid uptake were increased in myotubes from individuals with obesity. However, fatty acid oxidation was reduced, glucose oxidation was increased in myotubes from subjects with obesity compared to cells from lean. Pretreatment of myotubes with palmitic acid (PA) or eicosapentaenoic acid (EPA) for 24h increased glucose oxidation and oleic acid uptake. EPA pretreatment increased the glucose and fatty acid uptake and reduced leucine fractional oxidation in myotubes from donors with obesity. In conclusion, these results suggest that myotubes from individuals with obesity showed increased fatty acid, glucose, and amino acid uptake compared to cells from lean donors. Furthermore, myotubes from individuals with obesity had reduced fatty acid oxidative capacity, increased glucose oxidation, and a higher glycolytic reserve capacity compared to cells from lean donors. Fatty acid pretreatment enhances glucose metabolism, and EPA reduces oleic acid and leucine fractional oxidation in myotubes from donor with obesity, suggesting increased metabolic flexibility after EPA treatment.

Abstract 10905: Relationship of Eicosapentaenoic Acid and Docosahexaenoic Acid Dosage to Plaque Progression in Patients With Coronary Atherosclerosis Receiving Statin and Polyunsaturated Fatty Acid Therapy

Introduction: Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are omega-3 polyunsaturated fatty acids (PUFAs) extensively studied in atherosclerosis. Clinical endpoint and imaging studies have yielded convergent findings favoring pure EPA over mixed EPA/DHA formulations. The effects of EPA and DHA dose on coronary plaque dynamics, however, remain unknown, and could yield insights into the utility of these PUFAs in coronary artery disease. Methods: We considered longitudinal studies that compared coronary plaque change in patients receiving statin versus statin+PUFA therapy. Outcomes were % change in total and lipid plaque volume. Treatment effects were calculated as standardized mean difference (SMD), the mean % plaque volume change between statin and statin+PUFA cohorts divided by their pooled standard error. To isolate effects of EPA or DHA dose respectively, treatment arms were pooled by dosage of the PUFA of interest. To account for dependent samples, we fit hierarchical mixed effects models using robust variance estimation, assuming a correlation of 0.5 among treatment effects within multi-arm studies. Results: Among 555 screened articles, 11 studies met inclusion criteria. Among 1,070 patients, there were 14 treatment arms stratified by EPA dose, and 15 treatment arms stratified by DHA dose. Meta-regression revealed that EPA dose (g/day) correlated positively with treatment effect (β = 0.3 [0.1, 0.6], P = 0.02), while daily DHA dose correlated negatively with treatment effect (β = -0.4 [-0.7, -0.1], P = 0.01). We found no associations between EPA (β = 0.1 [-0.2, 0.4], P = 0.44) or DHA (β = -0.1 [-0.3, 0.2], P = 0.59) dose and treatment effects for lipid volume (Figure 1). Conclusions: Among cohorts receiving statin+PUFA therapy, we found a dose-dependent benefit of administered EPA on coronary plaque volume; the opposite was true for DHA. This adds to a growing body of evidence suggesting DHA may blunt beneficial effects of EPA in atherosclerosis.

Abstract 10318: Polyunsaturated Fatty Acids, EPA and DHA Possess a Potent P300-hat Inhibitor and Prevent Mi-Induced Development of Heart Failure in Rats

Introduction: The histone acetyltransferase (HAT) activity of p300 has a crucial role in the development of heart failure. Although many studies have shown a cardioprotective effect of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), omega-3 unsaturated fatty acids, little is known about the effects of these acids on cardiomyocyte hypertrophy. In this study, we investigated the effects of these acids on cardiomyocyte hypertrophy and the development of heart failure in rats with myocardial infarction (MI). Methods and Results: In cardiomyocytes, EPA and DHA (10 μM) significantly suppressed equally PE-induced cardiomyocyte hypertrophy, hypertrophy-response gene transcriptions, and acetylation of histone-H3K9. Furthermore, p300-induced hypertrophic responses were also suppressed by EPA and DHA. The result of an in vitro p300-HAT assay revealed that EPA and DHA directly inhibited p300-HAT activity (IC50: 37.8 μM, 30.6 μM) and induced allosteric inhibition of histones and competitive inhibition of acetyl-CoA in vitro . In addition, palmitic acid and stearic acid could not inhibit them. MI-operated rats (FS&lt;40%) were randomly assigned to 3 groups; vehicle (saline), EPA, and DHA (1g/kg). One week after the operation, oral administrations were repeated for 6 weeks. The echocardiographic analysis demonstrated that both EPA and DHA treatments prevented MI-induced left ventricular remodeling with preserved FS. Furthermore, EPA and DHA significantly suppressed the MI-induced increase in myocardial cell diameter, perivascular fibrosis, mRNA levels of hypertrophic and fibrotic markers, and acetylation of histone H3K9. In the left ventricle, EPA contents were lower than those of the other fatty acids, and no difference in each group. The EPA group exhibited higher docosapentaenoic acid (DPA) and DHA content than the vehicle group. The DHA group increased DHA content but not DPA and EPA contents. Conclusion: These results suggested that both EPA and DHA suppressed MI-induced development of heart failure through the inhibition of p300-HAT activity. The cardioprotective effect of EPA on MI might be attributed to the conversion of DHA or EPA metabolites.

Role of natural fatty acids in prophylaxis and treatment of cardiovascular diseases

Summary Multiple randomized controlled trials (RCTs) have assessed the effects of supplementation with eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) known as omega-3 polyunsaturated fatty acids (FAs), commonly called fish oils, on the occurrence of cardiovascular diseases. In a living organism, omega-3 FA (EPA and DHA) and omega-6 FA (arachidonic acid [AA]) are also involved in the formation of key regulators of platelet aggregation, vasodilation and inflammation. It is important to know that EPA and DHA act in different ways on membrane structure and lipid metabolism. For this reason, combining DHA with EPA may modify the clinical effects of only EPA treatment. The effects of omega-3 FAs on cardiovascular system remain uncertain. Two recent negative trials of EPA + DHA, STRENGTH and OMEMI, have put the utility of omega-3 FAs in preventing atherosclerotic cardiovascular events under debate. This paper presents the actual knowledge on the role of polyunsaturated acids in cardiovascular diseases.

Eicosapentaenoic Acid (EPA) Modulates Expression of Inflammatory Proteins in Pulmonary Endothelial Cells following Exposure to Air Pollution Particles

Lead Author's Financial Disclosures Nothing to disclose. Study Funding Amarin Pharma Inc. and Elucida Research. Background/Synopsis Air pollution contributes to global mortality by causing systemic inflammation and endothelial dysfunction in vascular disease, including atherosclerosis. The omega-3 fatty acid eicosapentaenoic acid (EPA) reduced cardiovascular events in high-risk patients (REDUCE-IT). EPA and omega-3 fatty acids can improve cardiac function and lipid levels in subjects exposed to air pollution particulate matter (PM) but underlying the mechanism is not understood. Objective/Purpose To test the ability of EPA to modulate expression of inflammatory proteins and related pathways in pulmonary endothelial cells following exposure to air pollution PMs of different sizes. Methods Human pulmonary ECs (PECs) were pretreated with EPA (40 micromolar) for 2 h before addition of particulate matter (PMs) with two different diameter ranges for 8 h. The PMs had an average of 5.9 micrometers from collected urban air (urban PMs) and 2.8 micrometers (fine PMs). PMs were delivered to the cells at 50 microgram/mL. Cell extracts from each treatment group were analyzed with LC/MS-based proteomics to measure relative expression levels of proteins. Only significant (p<0.05) changes in expression between treatment groups >1- fold were analyzed using differential enrichment analysis of proteomics data (DEP) and included in gene set enrichment analysis (GSEA). Results EPA significantly modulated expression of 205 and 347 proteins relative to fine and urban PMs, respectively. Among pathways modulated by both PMs was neutrophil degranulation (Gene Ontology ID: 0043312), where fine and urban PMs modulated 36 and 13 proteins, respectively. Common to both PMs were eight proteins, including 1.5-fold and 1.3-fold increases in C-X-C motif chemokine 6 (CXCL6). EPA treatment modulated 22 and 35 proteins associated with neutrophil degranulation compared to fine and urban PMs, respectively. Relative to fine PMs, EPA increased expression of heat shock protein 90-β; and decreased expression of interleukin enhancer-binding factor 2 (ILF2). Compared to urban PMs, EPA decreased expression of CXCL6 and increased expression of glutathione S-transferase P. Conclusions EPA significantly modulated expression of various inflammatory proteins in pulmonary ECs during exposure to multiple air pollution PMs. These findings support a novel vascular benefit for EPA under inflammatory conditions caused by air pollution PMs. Nothing to disclose.

The polyunsaturated fatty acids, EPA and DHA, ameliorate myocardial infarction-induced heart failure by inhibiting p300-HAT activity in rats

While the cardioprotective functions of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and omega-3 unsaturated fatty acids have been previously demonstrated, little is known about their effects on cardiomyocyte hypertrophy. In this study, we compared the effects of EPA and DHA on hypertrophic responses in cardiomyocytes and development of heart failure in rats with myocardial infarction (MI). Both EPA and DHA significantly suppressed phenylephrine- and p300-induced cardiomyocyte hypertrophy, transcription of hypertrophy response genes, and acetylation of histone H3K9 in cardiomyocytes. EPA and DHA directly inhibited p300-histone acetyltransferase activity (IC50: 37.8 and 30.6 μM, respectively). Further, EPA- and DHA-induced allosteric inhibition of histones and competitive inhibition of acetyl-CoA, and significantly prevented p300-induced hypertrophic responses. Rats with moderate MI (left ventricular fractional shortening [FS] <40%) were randomly assigned to three groups, namely, vehicle (saline), EPA (1 g/kg), and DHA (1 g/kg). One week after the operation, rats were orally administrated with test agents for 6 weeks. Echocardiographic analysis demonstrated that both EPA and DHA treatments preserved FS and prevented MI-induced left ventricular remodeling. Furthermore, EPA and DHA significantly suppressed the MI-induced increase in myocardial cell diameter, perivascular fibrosis, mRNA levels of hypertrophic markers, fibrosis, and acetylation of histone H3K9. The effects on hypertrophic responses and the development of heart failure were not different between EPA and DHA groups. Both EPA and DHA suppressed hypertrophic responses and the development of heart failure to the same extent through the inhibition of p300-HAT activity.