Biologic plausibility, cellular effects, and molecular mechanisms of eicosapentaenoic acid (EPA) in atherosclerosis

The effect of eight weeks combined training with omega-3 supplementation on the levels of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in older women

BACKGROUND

Elevated levels of ICAM-1 and VCAM-1 are significant risk factors for cardiovascular diseases. Conversely, the regulatory roles of physical activity and omega-3 supplementation in these factors have been reported. The primary aim of the present research was to investigate the impact of an eight-week combined (resistance-endurance) accompanied by omega-3 supplementation on ICAM-1 and VCAM-1 levels in elderly women.

METHODS

Forty elderly women, averaging 66.7 ± 4.13 years, were randomly assigned to four groups: placebo, omega-3 supplement, training, and training + omega-3. The combined exercise training program was implemented for eight weeks, three sessions per week. Aerobic training included 20 min of running at 60-70% of the reserve heart rate, while resistance training involved exercises at 70% of 1RM with 10 repetitions per exercise for two sets. The omega-3 and training + omega-3 groups consumed 2000 mg of omega-3 daily. Blood samples were collected 48 h after the last combined exercise training or omega-3 consumption, and the measured variables were analyzed using analysis of covariance test and SPSS-24 software.

RESULTS

ICAM-1 and VCAM-1 levels significantly decreased in the training and training + omega-3 groups (p < 0.001). The decrease in ICAM-1 within the training + omega-3 group was also significant compared to the training group (p = 0.024). Additionally, a significant reduction in insulin resistance and body fat percentage was observed in both the training and training + omega-3 groups (p < 0.001).

CONCLUSION

The present study's results indicate that omega-3 supplementation can enhance the effectiveness of combined training in regulating cardiovascular risk factors.

Omega-3 Fatty Acids and Risk of Ischemic Stroke in REGARDS

We examined associations between lipidomic profiles and incident ischemic stroke in the REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort. Plasma lipids (n = 195) were measured from baseline blood samples, and lipids were consolidated into underlying factors using exploratory factor analysis. Cox proportional hazards models were used to test associations between lipid factors and incident stroke, linear regressions to determine associations between dietary intake and lipid factors, and the inverse odds ratio weighting (IORW) approach to test mediation. The study followed participants over a median (IQR) of 7 (3.4-11) years, and the case-cohort substudy included 1075 incident ischemic stroke and 968 non-stroke participants. One lipid factor, enriched for docosahexaenoic acid (DHA, an omega-3 fatty acid), was inversely associated with stroke risk in a base model (HR = 0.84; 95%CI 0.79-0.90; P = 8.33 × 10-8) and fully adjusted model (HR = 0.88; 95%CI 0.83-0.94; P = 2.79 × 10-4). This factor was associated with a healthy diet pattern (β = 0.21; 95%CI 0.12-0.30; P = 2.06 × 10-6), specifically with fish intake (β = 1.96; 95%CI 0.95-2.96; P = 1.36 × 10-4). DHA was a mediator between fish intake and incident ischemic stroke (30% P = 5.78 × 10-3). Taken together, DHA-containing plasma lipids were inversely associated with incident ischemic stroke and mediated the relationship between fish intake and stroke risk.

Do patients benefit from omega-3 fatty acids?

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.

Omega-3 supplementation and outcomes of heart failure: A systematic review of clinical trials

BACKGROUNDS

Omega-3 supplements are endorsed for heart failure (HF) patients to reduce hospitalizations and mortality, offering anti-inflammatory and cardioprotective benefits.

METHODS

A comprehensive search was conducted in various databases until November 2022. Eligible studies included clinical trials on patients with HF. Data extraction covered study details, omega-3 specifics, outcomes, and limitations. The JADAD scale was used to assess the risk of bias in randomized controlled trials.

RESULTS

The review process involved 572 records from database searches, resulting in 19 studies after eliminating duplicates and screening. These studies assessed the impact of omega-3 on various clinical outcomes, such as mortality, hospitalization, cardiac function, and quality of life. Studied duration varied from weeks to years. Omega-3 supplementation demonstrated potential benefits such as improved heart function, reduced inflammation, and decreased risk of cardiovascular events.

CONCLUSION

Omega-3 supplementation could benefit heart disease treatment, potentially reducing therapy duration and improving outcomes. Starting omega-3 supplementation for HF patients seems favorable.

The multidimensional benefits of eicosapentaenoic acid: from heart health to inflammatory control

Eicosapentaenoic acid (EPA) is an omega-3 fatty acid found in fatty fish and fish oil supplements. Over the past few decades, research has suggested that EPA has various potential health benefits, particularly for heart health.

EPA has been associated with reduced inflammation, improved cholesterol levels, and reduced blood pressure, all of which can contribute to a lower risk of heart disease. Additionally, EPA has been found to reduce the risk of blood clots, which can lead to heart attacks and strokes. This comprehensive review article aims to summarize the current state of knowledge regarding the potential health benefits of EPA. We focus on its effects on cardiovascular health, inflammation, atherosclerotic plaques, blood clots, diabetes, obesity, and cancer. Finally, we provide an overview of the recommended daily dose of EPA for optimal health benefits.

This review highlights the importance of EPA in promoting overall health and well-being and provides insights into its potential therapeutic applications.

Association and Implications of Blood and Plaque n-3 Polyunsaturated Fatty Acid Composition in Patients Treated with Oral Eicosapentaenoic Acid before Carotid Endarterectomy

Long-chain n-3 polyunsaturated fatty acids (PUFA), especially eicosapentaenoic acid (EPA), have been shown to prevent atherosclerosis-related cardiovascular disease, including stroke. Recently, the ratio of serum EPA to arachidonic acid (AA; EPA/AA ratio) has been reported to be a biomarker to prevent cardiovascular disease. In this study, we evaluate whether the serum EPA/AA ratio would be a useful biomarker for determining the efficacy of orally administered EPA in preventing stroke by investigating tissue and serum EPA/AA ratios, serum inflammatory markers, and carotid artery intimamedia thickness (IMT). Patients with dyslipidemia, as the primary illness scheduled for carotid endarterectomy (CEA), were included and randomly assigned to the EPA group (EPA: 1,800 mg/day plus statin; 10 patients) or non-EPA group (statin only; 15 patients). PUFA fraction was evaluated in the tissue (post-CEA) and serum (pre-CEA and 6 months thereafter). As for the tissue PUFA fraction in the plaque, the EPA group had a significantly higher EPA/AA ratio (EPA group, 0.46; non-EPA group, 0.28; p  = 0.01). At 6 months postoperatively, the EPA group had a significantly higher serum EPA/AA ratio (baseline, 0.83; follow-up, 1.60; p  = 0.05). No significant differences were found for inflammatory markers and IMT. Both serum and tissue EPA/AA ratios were higher in patients treated with oral EPA. Serum EPA/AA ratio might be a useful biomarker for the efficacy of orally administered EPA.

High residual cardiovascular risk after lipid-lowering: prime time for Predictive, Preventive, Personalized, Participatory, and Psycho-cognitive medicine

As time has come to translate trial results into individualized medical diagnosis and therapy, we analyzed how to minimize residual risk of cardiovascular disease (CVD) by reviewing papers on "residual cardiovascular disease risk". During this review process we found 989 papers that started off with residual CVD risk after initiating statin therapy, continued with papers on residual CVD risk after initiating therapy to increase high-density lipoprotein-cholesterol (HDL-C), followed by papers on residual CVD risk after initiating therapy to decrease triglyceride (TG) levels. Later on, papers dealing with elevated levels of lipoprotein remnants and lipoprotein(a) [Lp(a)] reported new risk factors of residual CVD risk. And as new risk factors are being discovered and new therapies are being tested, residual CVD risk will be reduced further. As we move from CVD risk reduction to improvement of patient management, a paradigm shift from a reductionistic approach towards a holistic approach is required. To that purpose, a personalized treatment dependent on the individual's CVD risk factors including lipid profile abnormalities should be configured, along the line of P5 medicine for each individual patient, i.e., with Predictive, Preventive, Personalized, Participatory, and Psycho-cognitive approaches.

The Potential Cardiometabolic Effects of Long-Chain ω-3 Polyunsaturated Fatty Acids: Recent Updates and Controversies

Various health-related effects of long-chain (LC) ω-3 PUFAs, EPA, and DHA have been suggested. LC ω-3 PUFAs reduce TG concentrations and have anti-inflammatory, immunomodulatory, antiplatelet, and vascular protective effects. Controversially, they might help in restoring glucose homeostasis via the gut microbiota. However, previous studies have not shown the clear benefits of LC ω-3 PUFAs for CVDs. REDUCE-IT and STRENGTH-representative randomized controlled trials (RCTs) that examined whether LC ω-3 PUFAs would prevent major adverse cardiovascular (CV) events (MACE)-showed conflicting results with differences in the types, doses, or comparators of LC ω-3 PUFAs and study populations. Therefore, we performed a meta-analysis using major RCTs to address this inconsistency and assess the clinical and biological effects of LC ω-3 PUFAs. We included RCTs that involved ≥500 participants with ≥1 y follow-up. Of 17 studies involving 143,410 people, LC ω-3 PUFA supplementation showed beneficial effects on CV death (RR: 0.94; 95% CI: 0.88, 0.99; P = 0.029) and fatal or nonfatal MI (RR: 0.83; 95% CI: 0.72, 0.95; P = 0.010). RCTs on EPA alone showed better results for 3-point MACE, CV death, and fatal or nonfatal MI. However, the benefits were not found for fatal or nonfatal stroke, all-cause mortality, and hospitalization for heart failure. Of note, studies of both the EPA/DHA combination and EPA alone showed a significant increase in risk of new-onset atrial fibrillation. Thus, well-designed studies are needed to investigate the underlying mechanisms involved in the distinct effects of EPA compared with DHA on cardiometabolic diseases. This review discusses the potential benefits and safety of LC ω-3 PUFAs from a cardiometabolic perspective focusing on recent updates and controversies.

Combined Effect of Omega-3 Fatty Acid and Vitamin D 3 on Oxidized LDL-C and Non-HDL-C Levels in People With Vitamin D Deficiency: A Randomized Controlled Trial

ABSTRACT

The present randomized clinical trial (RCT) was conducted on Jordanian participants with vitamin D deficiency (VDD) with no other medical conditions, to evaluate the combined effect of 1,25-dihydroxy vitamin D 3 (Vit.D 3 ) and omega-3 fatty acid (n-3FA) supplements (D+) on oxidized low-density lipoprotein (Ox-LDL) and non-high-density lipoprotein cholesterol (non-HDL-C) levels as common predictors of cardiovascular diseases (CVDs). Participants were randomized into 4 groups as follows: a control group (C) that received no supplementations, a Vit.D 3 group that received 50,000 IU of Vit.D 3 every week, an n-3FA group that received 300 mg of omega-3 fatty acid every day, and a D+ group that received a combination of both supplements, with the same dosage administered by the previous groups but with a 4-6-hour time interval between Vit.D 3 and n-3FA administration to avoid any possible interaction. All supplementations were administered orally for 8 weeks. Forty-seven participants were allocated to each group. Twenty-six in the control group, 37 participants in the Vit.D 3 group, 37 participants in the n-3FA group, and 46 participants in the D+ group completed the study to the end. The D+ supplementations significantly increased non-HDL-C (118.99 ± 60.98 to 155.26 ± 43.36 mg/dL, P << 0.05) but decreased Ox-LDL-C levels (69.29 ± 37.69 to 52.81 ± 17.30 pg/mL, P = 0.03). The stepwise regression showed that the serum LDL-C level was the main independent variable involved in the elevation of non-HDL levels (R 2 = 0.837) observed at the end of the trial in the D+ group. The groups that were supplemented with either Vit.D 3 alone or n-3FA alone had an insignificant decrease in the level of Ox-LDL-C. In conclusion, despite the observed hyperlipidemic effect, the combination treatment is recommended by the research team because the decrease in Ox-LDL may offset the hyperlipidemic effect.

Role of Omega-3 Fatty Acids in Cardiovascular Disease: the Debate Continues

PURPOSE OF REVIEW

The omega-3 fatty acids (n3-FAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have recently undergone testing for their ability to reduce residual cardiovascular (CV) risk among statin-treated subjects. The outcome trials have yielded highly inconsistent results, perhaps attributable to variations in dosage, formulation, and composition. In particular, CV trials using icosapent ethyl (IPE), a highly purified ethyl ester of EPA, reproducibly reduced CV events and progression of atherosclerosis compared with mixed EPA/DHA treatments. This review summarizes the mechanistic evidence for differences among n3-FAs on the development and manifestations of atherothrombotic disease.

RECENT FINDINGS

Large randomized clinical trials with n3-FAs have produced discordant outcomes despite similar patient profiles, doses, and triglyceride (TG)-lowering effects. A large, randomized trial with IPE, a prescription EPA only formulation, showed robust reduction in CV events in statin treated patients in a manner proportional to achieved blood EPA concentrations. Multiple trials using mixed EPA/DHA formulations have not shown such benefits, despite similar TG lowering. These inconsistencies have inspired investigations into mechanistic differences among n3-FAs, as EPA and DHA have distinct membrane interactions, metabolic products, effects on cholesterol efflux, antioxidant properties, and tissue distribution. EPA maintains normal membrane cholesterol distribution, enhances endothelial function, and in combination with statins improves features implicated in plaque stability and reduces lipid content of plaques. Insights into reductions in residual CV risk have emerged from clinical trials using different formulations of n3-FAs. Among high-risk patients on contemporary care, mixed n3-FA formulations showed no reduction in CV events. The distinct benefits of IPE in multiple trials may arise from pleiotropic actions that correlate with on-treatment EPA levels beyond TG-lowering. These effects include altered platelet function, inflammation, cholesterol distribution, and endothelial dysfunction. Elucidating such mechanisms of vascular protection for EPA may lead to new interventions for atherosclerosis, a disease that continues to expand worldwide.

Cholesterol crystals and atherosclerotic plaque instability: Therapeutic potential of Eicosapentaenoic acid

Atherosclerotic plaques associated with acute coronary syndromes (ACS), i.e. culprit lesions, frequently feature a ruptured fibrous cap with thrombotic complications. On imaging, these plaques exhibit a low attenuation, lipid-rich, necrotic core containing cholesterol crystals and are inherently unstable. Indeed, cholesterol crystals are causally associated with plaque vulnerability in vivo; their formation results from spontaneous self-assembly of cholesterol molecules. Cholesterol homeostasis is a central determinant of the physicochemical conditions leading to crystal formation, which are favored by elevated membrane free cholesterol content in plaque endothelial cells, smooth muscle cells, monocyte-derived macrophages, and foam cells, and equally by lipid oxidation. Emerging evidence from imaging trials in patients with coronary heart disease has highlighted the impact of intervention involving the omega-3 fatty acid, eicosapentaenoic acid (EPA), on vulnerable, low attenuation atherosclerotic plaques. Thus, EPA decreased features associated with unstable plaque by increasing fibrous cap thickness in statin-treated patients, by reducing lipid volume and equally attenuating intraplaque inflammation. Importantly, atherosclerotic plaques rapidly incorporate EPA; indeed, a high content of EPA in plaque tissue is associated with decreased plaque inflammation and increased stability. These findings are entirely consistent with the major reduction seen in cardiovascular events in the REDUCE-IT trial, in which high dose EPA was administered as its esterified precursor, icosapent ethyl (IPE); moreover, clinical benefit was proportional to circulating EPA levels. Eicosapentaenoic acid is efficiently incorporated into phospholipids, where it modulates cholesterol-enriched domains in cell membranes through physicochemical lipid interactions and changes in rates of lipid oxidation. Indeed, biophysical analyses indicate that EPA exists in an extended conformation in membranes, thereby enhancing normal cholesterol distribution while reducing propagation of free radicals. Such effects mitigate cholesterol aggregation and crystal formation. In addition to its favorable effect on cholesterol domain structure, EPA/IPE exerts pleiotropic actions, including antithrombotic, antiplatelet, anti-inflammatory, and proresolving effects, whose plaque-stabilizing potential cannot be excluded. Docosahexaenoic acid is distinguished from EPA by a higher degree of unsaturation and longer carbon chain length; DHA is thus predisposed to changes in its conformation with ensuing increase in membrane lipid fluidity and promotion of cholesterol aggregation into discrete domains. Such distinct molecular effects between EPA and DHA are pronounced under conditions of high cellular cholesterol content and oxidative stress. This review will focus on the formation and role of cholesterol monohydrate crystals in destabilizing atherosclerotic plaques, and on the potential of EPA as a therapeutic agent to attenuate the formation of deleterious cholesterol membrane domains and of cholesterol crystals. Such a therapeutic approach may translate to enhanced plaque stability and ultimately to reduction in cardiovascular risk.

Emphasis on Icosapent Ethyl for Cardiovascular Risk Reduction: A Systematic Review

Despite the widespread use of lipid-lowering agents such as statins, cardiovascular disease (CVD) remains the leading cause of mortality worldwide. Icosapent ethyl (IPE) (Vascepa), an ethyl ester of the omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA), has gained widespread popularity as an adjunctive agent that targets multiple and additional mechanisms linked to the incidence of cardiovascular (CV) events and the causative pathway of atherosclerosis. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 standards were used to conduct this systematic review. In this review, we assessed various studies from PubMed, PubMed Central (PMC), and Google Scholar to evaluate the mechanisms of action and beneficial effects of IPE in the reduction of CVD outcomes. The Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT) has demonstrated a significant reduction in CV mortality with 4 g/day IPE as compared to placebo. All other trials and observational studies have supported the role of Vascepa in hypertriglyceridemia and CV risk reduction. In conclusion, the use of IPE has been shown to significantly reduce triglyceride levels and reduce CV risks in patients receiving optimal statin therapy.

Changes in the Eicosapentaenoic Acid to Arachidonic Acid Ratio in Serum over 10 Years in a Japanese Community: The Hisayama Study

AIM

Circulating omega-3 and omega-6 polyunsaturated fatty acids may to contribute to cardiovascular health at the population level. Over a decade, we investigated changes in the serum eicosapentaenoic acid (EPA) to arachidonic acid (AA) ratio, and in serum concentrations of the individual fatty acids, in a Japanese community.

METHODS

Community surveys took place in 2002-2003 and 2012-2013 in a rural area of Japan. The community surveys included 3,194 and 3,220 community dwellers aged ≥ 40 years who did not take EPA medication in 2002-2003 and 2012-2013, respectively. Fatty acid fractionations in serum were measured using a gas chromatography method. Changes in the serum EPA/AA ratio over time were examined using linear mixed models.

RESULTS

Overall, the average serum EPA/AA ratio decreased over the 10 years. A decreasing trend in the serum EPA/AA ratio occurred in all age groups except participants aged ≥ 80 years, with larger decreases in the younger age groups. A similar decline in serum EPA/AA ratio occurred in participants with and those without lipid-lowering therapy. Serum EPA concentrations were slightly increased in the whole population but remained stable or even decreased in participants aged 40-69. In contrast, the average serum AA concentrations increased in all age groups.

CONCLUSION

In a Japanese community, the serum EPA/AA ratio decreased over 10 years at the population level, especially in middle-aged participants.

Potential effects of icosapent ethyl on cardiovascular outcomes in cigarette smokers: REDUCE-IT smoking

AIMS

Cigarette smoking is among the most well-established risk factors for adverse cardiovascular outcomes. We sought to determine whether icosapent ethyl (IPE), a highly purified form of eicosapentaenoic acid with antiatherothrombotic properties, may reduce the excessive risk of cardiovascular disease (CVD) attributable to smoking.

METHODS AND RESULTS

Reduction of Cardiovascular Events with Icosapent Ethyl Trial (REDUCE-IT) was a multinational, double-blind trial that randomized 8179 statin-treated patients with elevated triglycerides and CV risk to IPE or placebo, with a median follow-up period of 4.9 years. Icosapent ethyl reduced the primary composite endpoint [CV death, non-fatal myocardial infarction (MI), non-fatal stroke, coronary revascularization, or hospitalization for unstable angina] by 25% (P < 0.0001). In the current analyses, the effect of IPE was evaluated in REDUCE-IT using post hoc analyses based on smoking history. Groups were classified as current smokers (n = 1241), former smokers (n = 3672), and never smokers (n = 3264). Compared with placebo, IPE use in combined current and former smokers (n = 4913) was associated with significant reductions in time to the primary composite endpoint {hazard ratio: 0.77 [95% confidence interval (CI): 0.68-0.87]; P < 0.0001} and in total events [rate ratio: 0.71 (95% CI: 0.61-0.82); P < 0.0001]. These benefits remained significant when subdivided into current and former smokers (P = 0.04, P = 0.005), with reductions in the key secondary composite endpoint (P < 0.0001) and in the individual components of CV death or non-fatal MI (P = 0.04, P = 0.01) and fatal or non-fatal MI (P = 0.009, P = 0.01), respectively. Benefits were consistent and significant in non-smokers as well. Overall, there were similar estimated rates of first occurrences of primary CVD endpoints in current smokers (23.8%) and former smokers (23.0%) assigned to IPE compared with never smokers on placebo (25.7%).

CONCLUSION

In REDUCE-IT, IPE treatment was associated with a reduced risk of CV events in current and former smokers to levels observed in never smokers. While smoking cessation should always be recommended, these data raise the possibility that IPE treatment may attenuate CV hazards attributable to smoking.

A biological rationale for the disparate effects of omega-3 fatty acids on cardiovascular disease outcomes

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.

Sea Bass Essence from Lates calcarifer Improves Exercise Performance and Anti-Fatigue in Mice

Sea bass (Lates calcarifer) is rich in protein, amino acids, and long-chain omega 3 (omega-3), which have many health benefits. In East Asian food culture, soup is often eaten as a nutritional supplement. The purpose of this study was to investigate the benefits of Hi-Q sea bass essence (SBE) supplementation for improved exercise performance and anti-fatigue. Fifty male Institute of Cancer Research (ICR) mice were divided to five groups (10 mice/group) and administered different doses of SBE (EC): (1) vehicle (water); (2) isocaloric (0.94 g casein/kg/mice/day); (3) SBE-1X (1.04 g/kg/mice/day); (4) SBE-2X (2.08 g/kg/mice/day); and (5) SBE-4X (4.16 g/kg/mice/day). We found that SBE supplementation significantly improved more than 1.96-fold endurance exercise performance (p < 0.05) and more than 1.13-fold glycogen storage in the liver and muscles (p < 0.05), and had dose-dependent by SBE dose (p < 0.05). In addition, supplementation with SBE at different doses had significant effects on the fatigue-related biochemical markers, i.e., lactate, ammonia, and blood urea nitrogen (BUN) levels were reduced significantly (p < 0.05), and were also dose-dependent. In conclusion, supplementation with SBE for 4 weeks was able to effectively improve exercise performance and had an anti-fatigue effect. In addition, it did not cause any physiological or histopathological damage.

Omega-3-fatty acids: Do they prevent cardiovascular disease?

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.

The Influence of Eicosapentaenoic Acid to Arachidonic Acid Ratio on Long-term Cardiovascular Events Following Percutaneous Coronary Intervention

Objective The relationship between cardiovascular disease and the serum polyunsaturated fatty acid parameters has been reported. The aim of the present study was to investigate the association between the eicosapentaenoic acid and arachidonic acid (EPA/AA) ratio and long-term cardiovascular events in patients with coronary artery disease. Methods We identified a total of 831 patients who underwent percutaneous coronary intervention and whose EPA/AA ratio was available. The patients were divided into two groups according to their serum EPA/AA ratio (median, 0.29; interquartile range 0.19-0.47): those in the lower quartile of EPA/AA ratios (Low EPA/AA group; n=231) and all other subjects (High EPA/AA group; n=600). The primary endpoints included a composite of cardiovascular death, myocardial infarction, and ischemic stroke. Results Patients in the Low EPA/AA group were significantly younger (66.0±12.6 years vs. 69.9±9.3 years, p<0.001), current smokers (33.3% vs. 22.7%, p=0.002), and had a history of myocardial infarction (20.3% vs. 12.3%, p=0.003). During the follow-up (median, 1,206 days; interquartile range, 654-1,910 days), the occurrence of the primary endpoint was significantly higher in the Low EPA/AA group than in the High EPA/AA group. Of note, the rate of cardiovascular death was significantly higher in the Low EPA/AA group, and the rates of myocardial infarction and stroke tended to be higher. Conclusion A low EPA/AA ratio was associated with long-term adverse cardiovascular events in Japanese patients with coronary artery disease.

Effects of fatty acids on T cell function: role in atherosclerosis

T cells are among the most common cell types present in atherosclerotic plaques and are increasingly being recognized as a central mediator in atherosclerosis development and progression. At the same time, triglycerides and fatty acids have re-emerged as crucial risk factors for atherosclerosis. Triglycerides and fatty acids are important components of the milieu to which the T cell is exposed from the circulation to the plaque, and increasing evidence shows that fatty acids influence T cell function. In this Review, we discuss the effects of fatty acids on four components of the T cell response - metabolism, activation, proliferation and polarization - and the influence of these changes on the pathogenesis of atherosclerosis. We also discuss how quiescent T cells can undergo a type of metabolic reprogramming induced by exposure to fatty acids in the circulation that influences the subsequent functions of T cells after activation, such as in atherosclerotic plaques.

Omega-3 and omega-6 fatty acids have distinct effects on endothelial fatty acid content and nitric oxide bioavailability

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.

The role of icosapent ethyl in cardiovascular risk reduction

PURPOSE OF REVIEW

Elevated levels of triglycerides, independent of low-density lipoprotein cholesterol (LDL-C) levels and statin therapy, are associated with heightened cardiovascular risk.

RECENT FINDINGS

Mixed omega-3 fatty acid formulations, which contain varying amounts of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), lower triglycerides levels but trial results with omega-3 fatty acids combinations have generally been neutral for cardiovascular outcomes. In contrast, the REDUCE-IT trial with icosapent ethyl (IPE), a highly purified ethyl ester of EPA, demonstrated reduced cardiovascular risk in individuals with established atherosclerotic cardiovascular disease or diabetes with at least one additional risk factor, despite having relatively well controlled LDL-C levels but triglycerides at least 135 mg/dl while on statin therapy. IPE offers an important new avenue for cardiovascular risk management in statin-treated individuals with elevated triglycerides.

SUMMARY

This review summarizes the results from outcome trials conducted with omega-3 fatty acids, differentiating between those with combinations of EPA/DHA and those with pure EPA, as well as imaging and preclinical data that help explain the different cardiovascular efficacy observed. A list of frequently asked questions with evidence-based responses is provided to assist our colleagues and their patients in the shared-decision process when considering if IPE is appropriate for cardiovascular risk reduction.

The role of eicosapentaenoic acid in reducing important cardiovascular events, including coronary revascularization

The omega-3 fatty acid eicosapentaenoic acid has an important role in human health. The Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT) examined the prescription omega-3 fatty acid icosapent ethyl (IPE) in patients with established cardiovascular disease (CVD) or with diabetes plus additional CVD risk factors. The trial found a large reduction in CVD events, including significant reductions in CVD death, myocardial infarction, stroke, coronary revascularization, and hospitalization for unstable angina. These results led to the regulatory approval of IPE in a population similar to REDUCE-IT participants in the United States, Canada, United Kingdom, and the European Union. Moreover, multiple international guidelines have endorsed the use of IPE in such individuals. A secondary analysis of REDUCE-IT examined the endpoint of coronary artery revascularization. This analysis showed a significant reduction not only in coronary revascularization overall but also in elective, urgent, and emergent coronary revascularization. Additionally, IPE significantly reduced the need for both percutaneous coronary intervention and for coronary artery bypass graft surgery. Coronary imaging studies have demonstrated significant decreases in rates of plaque progression with IPE, with significant effects within 6-9 months. In parallel, experimental findings corroborate several effects of IPE that provide mechanisms that could contribute to the profound reductions in multiple types of ischemic events, including percutaneous and surgical coronary revascularization. Future trials should explore potential benefits of initiation of IPE at the time of revascularization in broader populations, potentially in conjunction with loading doses.

EPA and DHA containing phospholipids have contrasting effects on membrane structure

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/ų 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.

A Fishy Topic: VITAL, REDUCE-IT, STRENGTH, and Beyond: Putting Omega-3 Fatty Acids into Practice in 2021

PURPOSE OF REVIEW

To examine recently published data from clinical outcome and arteriographic studies that examined the addition of omega-3 fatty acids, eicosapentaenoic acid (EPA) + docosahexanoic acid (DHA), to standard of care therapy on cardiovascular disease (CVD) risk.

RECENT FINDINGS

Several trials that tested purified EPA (JELIS, REDUCE-IT, EVAPORATE) were associated with reduced CVD risk and regression of low attenuation coronary plaque volume, whereas studies that employed the combination EPA/DHA (VITAL, OMEMI, STRENGTH) failed to derive clinical benefit. Trials testing purified EPA consistently demonstrated reduction in atheromatous volume or CVD events beyond standard of care therapies, whereas the combination of EPA/DHA did not, despite producing similar reductions in triglycerides. Experimental and in vitro data suggest that compared to DHA, EPA exhibits antioxidant, anti-inflammatory, and membrane stabilizing properties that enhance vascular function and CVD risk. Consequently, purified EPA appears to be the treatment of choice for high-risk patients with hypertriglyceridemia.

Update on the omega-3 fatty acid trial landscape: A narrative review with implications for primary prevention

Residual risk mediated by hypertriglyceridemia among statin-treated individuals is an important clinical and public health challenge. Niacin, fibrates and omega-3 FA are three classes of non-statin agents with demonstrated TG-lowering effects. Randomized controlled trials of niacin and fibrates have been consistently negative, but the trial landscape for two key sources of omega-3 FAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is more complex. Clinical trials evaluating omega-3 FA can be differentiated into those that studied mixed formulations (EPA + DHA) and those that studied EPA alone. Those assessing the impact of mixed formulations have not consistently demonstrated CVD risk reduction, whereas trials of EPA alone have been successful. Two recent trials of mixed formulations - STRENGTH (Long-Term Outcomes Study to Assess Statin Residual Risk with Epanova in High Cardiovascular Risk Patients with Hypertriglyceridemia) and OMEMI (Omega-3 fatty acids in Elderly patients with Myocardial Infarction) - studied contemporarily treated patients with mixed EPA + DHA formulations at higher doses than before and showed no benefit, thus adding valuable information to our overall understanding of this evolving therapeutic class. In this review, we contextualize the findings of STRENGTH and OMEMI within the existing omega-3 FA clinical trial landscape and look ahead to how future trials can inform existing knowledge gaps, particularly with regards to the applicability of these agents within the primary prevention realm.

EPA's pleiotropic mechanisms of action: a narrative review

Treatment with icosapent ethyl 4 g/day, a highly purified and stable ethyl ester of eicosapentaenoic acid (EPA), demonstrated a significant reduction in atherosclerotic cardiovascular disease (ASCVD) events and death in REDUCE-IT. However, analyses of REDUCE-IT and meta-analyses have suggested that this clinical benefit is greater than can be achieved by triglyceride reduction alone. EPA therefore may have additional pleiotropic effects, including anti-inflammatory and anti-aggregatory mechanisms. EPA competes with arachidonic acid for cyclooxygenase and lipoxygenase, producing anti-inflammatory and anti-aggregatory metabolites rather than the more deleterious metabolites associated with arachidonic acid. Changing the EPA:arachidonic acid ratio may shift metabolic status from pro-inflammatory/pro-aggregatory to anti-inflammatory/anti-aggregatory. EPA also has antioxidant effects and increases synthesis of nitric oxide. Incorporation of EPA into phospholipid bilayers influences membrane structure and may help to prevent cardiac arrhythmias. Clinically, this may translate into improved vascular health, including regression of atherosclerotic plaque. Overall, EPA has a range of pleiotropic effects that contribute to a reduction in ASCVD.

Effect of icosapent ethyl on progression of coronary atherosclerosis in patients with elevated triglycerides on statin therapy: final results of the EVAPORATE trial

Aims

Despite the effects of statins in reducing cardiovascular events and slowing progression of coronary atherosclerosis, significant cardiovascular (CV) risk remains. Icosapent ethyl (IPE), a highly purified eicosapentaenoic acid ethyl ester, added to a statin was shown to reduce initial CV events by 25% and total CV events by 32% in the REDUCE-IT trial, with the mechanisms of benefit not yet fully explained. The EVAPORATE trial sought to determine whether IPE 4 g/day, as an adjunct to diet and statin therapy, would result in a greater change from baseline in plaque volume, measured by serial multidetector computed tomography (MDCT), than placebo in statin-treated patients.

Methods and results

A total of 80 patients were enrolled in this randomized, double-blind, placebo-controlled trial. Patients had to have coronary atherosclerosis as documented by MDCT (one or more angiographic stenoses with ≥20% narrowing), be on statin therapy, and have persistently elevated triglyceride (TG) levels. Patients underwent an interim scan at 9 months and a final scan at 18 months with coronary computed tomographic angiography. The pre-specified primary endpoint was change in low-attenuation plaque (LAP) volume at 18 months between IPE and placebo groups. Baseline demographics, vitals, and laboratory results were not significantly different between the IPE and placebo groups; the median TG level was 259.1 ± 78.1 mg/dL. There was a significant reduction in the primary endpoint as IPE reduced LAP plaque volume by 17%, while in the placebo group LAP plaque volume more than doubled (+109%) (P = 0.0061). There were significant differences in rates of progression between IPE and placebo at study end involving other plaque volumes including fibrous, and fibrofatty (FF) plaque volumes which regressed in the IPE group and progressed in the placebo group (P < 0.01 for all). When further adjusted for age, sex, diabetes status, hypertension, and baseline TG, plaque volume changes between groups remained significantly different, P < 0.01. Only dense calcium did not show a significant difference between groups in multivariable modelling (P = 0.053).

Conclusions

Icosapent ethyl demonstrated significant regression of LAP volume on MDCT compared with placebo over 18 months. EVAPORATE provides important mechanistic data on plaque characteristics that may have relevance to the REDUCE-IT results and clinical use of IPE.

Coronary heart disease risk: Low-density lipoprotein and beyond

Coronary heart disease (CHD) is the leading cause of morbidity and mortality world-wide and has been characterized as a chronic immunoinflammatory, fibroproliferative disease fueled by lipids. Great advances have been made in elucidating the complex mechanistic interactions among risk factors associated with CHD, yielding abundant success towards preventive measures and the development of pharmaceuticals to prevent and treat CHD via attenuation of lipoprotein-mediated risk. However, significant residual risk remains. Several potentially modifiable CHD risk factors ostensibly contributing to this residual risk have since come to the fore, including systemic inflammation, diabetes mellitus, high-density lipoprotein, plasma triglycerides (TG) and remnant lipoproteins (RLP), lipoprotein(a) (Lp[a]), and vascular endothelial dysfunction (ED). Herein, we summarize the body of evidence implicating each of these risk factors in residual CHD risk.

Cardiovascular effects of omega-3 fatty acids: Hope or hype?

Omega-3 fatty acids have emerged as a new option for controlling the residual risk for cardiovascular disease (CVD) in the statin era after a clinical trial (REDUCE-IT) reported positive results with icosapent ethyl (IPE) in patients receiving maximally tolerated statin therapy. However, another trial which used high dose eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) combination (STRENGTH) has failed. Together, these results raise clinically important questions. Are effects of omega-3 fatty acids neutral or beneficial in patients on statin therapy, or perhaps even harmful? The current contradictory results could be attributed to different types of omega-3 fatty acids (only EPA or combination of EPA + DHA), doses (higher vs. lower dose) of omega-3 fatty acids or different comparators (corn oil or mineral oil), as well as the underlying severity of the CVD risk or use of statins. Together with these issues, we will discuss different biological and clinical effects of various types of omega-3 fatty acids and then interpret different results of past and current clinical studies and propose practical suggestions, which could be applied in patient management.

The case for adding eicosapentaenoic acid (icosapent ethyl) to the ABCs of cardiovascular disease prevention

The high-purity eicosapentaenoic acid (EPA) prescription fish oil-derived omega-3 fatty acid (omega-3), icosapent ethyl (IPE), was recently approved by the United States Food and Drug Administration (FDA) for cardiovascular disease (CVD) prevention in high-risk patients. This approval is based on the 25% CVD event risk reduction observed with IPE in the pre-specified primary composite endpoint (cardiovascular [CV] death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or hospitalization for unstable angina) in the landmark Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT). Notably, this reduction in CVD event risk with IPE was an incremental benefit to well-controlled low-density lipoprotein cholesterol; patients in REDUCE-IT had elevated triglyceride (TG) levels (135-499 mg/dL) and either had a history of atherosclerotic CVD or diabetes with additional CV risk factors. Given the CVD event risk reduction in REDUCE-IT, within a year following trial results, several global medical societies added IPE to their clinical guidelines. IPE is a stable, highly purified, FDA-approved prescription EPA ethyl ester. In contrast, mixed omega-3 products (docosahexaenoic acid + EPA combinations) have limited or no evidence for CVD event risk reduction, and nonprescription fish oil dietary supplements are not regulated as medicine by the FDA. We offer our perspective and rationale for why this evidence-based EPA-only formulation, IPE, should be added to the 'E' in the ABCDEF methodology for CV prevention. We provide multiple lines of evidence regarding an unmet need for CVD prevention beyond statin therapy, IPE clinical trials, IPE cost-effectiveness analyses, and proposed pleiotropic (non-lipid) mechanisms of action of EPA, as well as other relevant clinical considerations. See Figure 1 for the graphical abstract.[Figure: see text].

Lipid Management in Patients Presenting With Acute Coronary Syndromes: A Review

Despite many improvements in its prevention and management, acute coronary syndrome (ACS) remains a major cause of morbidity and mortality in the developed world. Lipid management is an important part of secondary prevention after ACS, but many patients currently remain undertreated and do not attain guideline‐recommended levels of low‐density lipoprotein cholesterol reduction. This review details the current state of evidence on lipid management in patients presenting with ACS, provides directions for identification of patients who may benefit from early escalation of lipid‐lowering therapy, and discusses novel lipid‐lowering medication that is currently under investigation in clinical trials. Moreover, a treatment algorithm aimed at attaining guideline‐recommended low‐density lipoprotein cholesterol levels is proposed. Despite important advances in the initial treatment and secondary prevention of ACS, ≈20% of ACS survivors experience a subsequent ischemic cardiovascular event within 24 months, and 5‐year mortality ranges from 19% to 22%. Knowledge of the current state of evidence‐based lipid management after ACS is of paramount importance to improve outcomes after ACS.

Relationships of Fatty Acids, Delta-5 Desaturase Activity, and Lipid Profiles in Men with Acute Coronary Syndrome

AIMS

We evaluated the relationship between the ratios of eicosapentaenoic acid and arachidonic acid (EPA/AA), docosahexaenoic acid (DHA)/AA, and delta-5 desaturase activity (D5D) and atherogenic lipid profiles (ALP) and coronary atherosclerosis.

METHODS

Polyunsaturated fatty acids (PUFA) and ALP were assessed in 436 men with the first episode of acute coronary syndrome (ACS) not take any lipid-lowering drugs. D5D was estimated as the ratio of AA to dihomogamma-linolenic acid (DGLA). These biomarkers were compared between the lower and higher levels of EPA/AA (0.41) or DHA/AA (0.93) according to the levels in Japanese general population. The thrombolysis in myocardial infarction flow (TIMI) grade of the culprit coronary artery was visually estimated during the initial angiography.

RESULTS

Approximately 70% of patients had low EPA/AA or DHA/AA. Serum levels of LDL-cholesterol, apolipoprotein B (apoB), and remnant lipoprotein cholesterol (RL-C) were significantly higher in the low EPA/AA or DHA/AA groups, while those of triglycerides and malondialdehyde-modified LDL (MDA-LDL) were significantly higher in the low EPA/AA group alone. The levels of EPA, EPA/AA, DHA/AA, and HbA1c increased and those of DGLA and apoA1 decreased with increasing number of stenotic vessels. Patients with three stenotic coronary vessels or TIMI grade ≥ 1 had significantly higher EPA levels compared with the others. The levels of LDL-cholesterol, non-HDL-cholesterol, triglycerides, small dense LDL-cholesterol, RL-C, MDA-LDL, apoB, and apoE decreased progressively and those of EPA, DHA, EPA/AA and HDL-cholesterol increased as D5D increased.

CONCLUSIONS

The EPA/AA is a superior risk marker than DHA/AA in term of correlation with ALP in ACS patients.

High levels of eicosapentaenoic acid are associated with lower pericoronary adipose tissue attenuation as measured by coronary CTA

BACKGROUND AND AIMS

Higher pericoronary adipose tissue (PCAT) attenuation, a novel marker of inflammation in coronary CT angiography (CTA), has been shown to indicate increased cardiac mortality. Supplementation of eicosapentaenoic acid (EPA) has been shown to decrease cardiovascular death. Whether blood levels of n-3 fatty acids are associated with differences in PCAT attenuation is unknown.

METHODS

This is a cross-sectional analysis including 64 symptomatic patients who underwent coronary CTA. PCAT attenuation was measured in Hounsfield Units (HU) around the proximal 40 mm of the right coronary artery using semi-automated software. Erythrocyte membrane fatty acid composition was analyzed using gas chromatography. Individual fatty acids were expressed as a percentage of total identified fatty acids.

RESULTS

The patient cohort was divided into two groups using the median PCAT attenuation of -78.1 HU (each n = 32). No differences were seen in age, sex, BMI or traditional cardiovascular risk factors (CVRF) between groups (all p > 0.05). In univariable analysis, significantly higher values of EPA (1.00% [0.78; 1.26] vs. 0.78% [0.63; 0.99]; p = 0.02) were seen in patients with lower PCAT attenuation. All other fatty acids showed no differences (all p > 0.05). Moreover, a significant negative correlation was seen between PCAT attenuation and EPA (CC: 0.38; p = 0.002). In multivariable analysis, an inverse association of EPA with PCAT attenuation existed (ß = -0.31, p = 0.017), independent of age, gender, BMI and number of CVRF (all p > 0.1).

CONCLUSIONS

High levels of EPA are associated with lower PCAT attenuation on coronary CTA. This may indicate a different composition of pericoronary adipose tissue, potentially caused by a lower degree of coronary inflammation.

Beyond cardiovascular medicine: potential future uses of icosapent ethyl

The REDUCE-IT trial demonstrated that icosapent ethyl, an ethyl ester of eicosapentaenoic acid (EPA), reduced cardiovascular events in an at-risk population by a substantial degree. While the cardiovascular protective properties of this compound are now proven, several other potential uses are being actively explored in clinical studies. These areas of investigation include cancer, inflammatory bowel disease, infections, Alzheimer’s disease, dementia, and depression. The next decade promises to deepen our understanding of the beneficial effects that EPA may offer beyond cardiovascular risk reduction.

Omega n-3 Supplementation: Exploring the Cardiovascular Benefits Beyond Lipoprotein Reduction

PURPOSE OF REVIEW

Hypertriglyceridaemia is a highly prevalent disorder worldwide. Genetic and Mendelian randomization studies have suggested that triglyceride (TG)-rich lipoproteins are causal risk factors for coronary heart disease and contribute to the residual cardiovascular risk observed in patients optimally treated with statins. However, clinical trials failed to show cardiovascular benefits of TG-lowering; in this context, trials with omega-3 fatty acids provided contrasting results. Few trials have tested the supplementation of EPA alone rather than the combination of EPA + DHA. The JELIS study showed that EPA 1.8 g/day significantly reduced CV events in hypercholesterolaemic patients given statins, an effect that was independent on lipid reduction.

RECENT FINDINGS

The REDUCE-IT trial showed that high-dose (4 g/day) EPA significantly reduces the incidence of major cardiovascular events compared with placebo in patients with elevated TG levels. The clinical benefit was higher than expected by the reduction of TG-rich lipoprotein levels. Recent data support the efficacy of high-dose EPA supplementation on a background of optimal LDL-C-lowering therapy as a key approach to achieve a further and significant reduction of CV events in very-high CV risk patients with persistent hypertriglyceridaemia. The effect on lipids does not appear to fully explain the CV benefit, and additional mechanisms of action of EPA likely contribute to the cardiovascular protection, including the reduction of inflammation and platelet aggregation. Current guidelines recommend using high-dose EPA in combination with a statin in high/very-high CV risk patients with mild-to-moderate elevation of plasma TG to reduce the residual CV risk.

Impact of expanded FDA indication for icosapent ethyl on enhanced cardiovascular residual risk reduction

Hypertriglyceridemia is associated with increased cardiovascular disease (CVD) risk. The Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT) demonstrated that the purified, stable ethyl ester of eicosapentaenoic acid, icosapent ethyl (IPE), added to statins reduced CVD events by 25% (p < 0.001), leading to an expanded indication in the USA. IPE is now approved as an adjunct to maximally tolerated statins to reduce CVD event risk in adults with triglyceride (TG) levels ≥150 mg/dl and either established CVD or diabetes mellitus plus ≥2 additional CVD risk factors. The new indication allows co-administration of IPE for elevated TG levels with statin treatment, enabling effective residual risk reduction in a broader at-risk population beyond what can be achieved with intensive low-density lipoprotein cholesterol control alone.

Krill Oil Has Different Effects on the Plasma Lipidome Compared with Fish Oil Following 30 Days of Supplementation in Healthy Women: A Randomized Controlled and Crossover Study

This is a follow-up of our previous postprandial study and it focused on the plasma lipidomic responses to 30 days of krill oil (KO) versus fish oil (FO) supplementations in healthy women. Eleven women (aged 18–50 years) consumed KO or FO for 30 days in a randomized, cross-over study, with at least a four-week washout period between supplementations. The daily supplements provided 1.27 g/day of long-chain (LC) omega-3 polyunsaturated fatty acids (PUFA) from KO (containing 0.76 g eicosapentaenoic acid (EPA), 0.42 g docosahexaenoic acid (DHA)) and 1.44 g/day from FO (containing 0.79 g EPA, 0.47 g DHA). Fasting plasma samples at days 0, 15, and 30 were analyzed using gas chromatography and liquid chromatography electrospray ionisation-tandem mass spectrometry. KO resulted in a significantly greater relative area under the curve (relAUC) for plasma EPA after 30 days. Lipidomic analysis showed that 26 of 43 lipid molecular species had a significantly greater relAUC in the KO group, while 17/43 showed a significantly lower relAUC compared with the FO group. More than 38% of the lipids species which increased more following KO contained omega-3 PUFA, while where FO was greater than KO, only 12% contained omega-3 PUFA. These data show that KO and FO do not have equivalent effects on the plasma lipidome.

Targeting hypertriglyceridemia to mitigate cardiovascular risk: A review

A causal relationship between elevated triglycerides and cardiovascular disease is controversial, as trials of triglyceride-lowering treatments have not shown significant impact on cardiovascular outcomes. However, hypertriglyceridemia is associated with atherogenesis and risk for acute cardiovascular events that persist despite optimal statin treatment. Although most trials of triglyceride-lowering treatments have been negative, in trials of niacin and fibrates, subgroup analyses in patients with higher baseline triglycerides and lower HDL-C levels suggest reduced incidence of cardiovascular endpoints. The REDUCE-IT trial demonstrated that addition of purified prescription eicosapentaenoic acid (icosapent ethyl) 4 ​g/day in high-risk patients with triglyceride levels 135–499 ​mg/dL and optimized statin treatment significantly reduced cardiovascular events versus placebo (hazard ratio 0.75; 95% confidence interval 0.68–0.83; P ​< ​0.001). Benefit was seen regardless of baseline and on-treatment triglyceride levels, suggesting that other effects of eicosapentaenoic acid besides triglyceride reduction may have played a role.

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Hypertriglyceridemia is associated with atherogenesis & cardiovascular event risk.

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Most triglyceride treatment cardiovascular outcomes trials have been negative.

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However, icosapent ethyl significantly reduced cardiovascular events in REDUCE-IT.

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Effects of icosapent ethyl beyond triglyceride reduction may play a role.

Effects of Eicosapentaenoic Acid on Arterial Calcification

Arterial calcification is a hallmark of advanced atherosclerosis and predicts cardiovascular events. However, there is no clinically accepted therapy that prevents progression of arterial calcification. HMG-CoA reductase inhibitors, statins, lower low-density lipoprotein-cholesterol and reduce cardiovascular events, but coronary artery calcification is actually promoted by statins. The addition of eicosapentaenoic acid (EPA) to statins further reduced cardiovascular events in clinical trials, JELIS and REDUCE-IT. Additionally, we found that EPA significantly suppressed arterial calcification in vitro and in vivo via suppression of inflammatory responses, oxidative stress and Wnt signaling. However, so far there is a lack of evidence showing the effect of EPA on arterial calcification in a clinical situation. We reviewed the molecular mechanisms of the inhibitory effect of EPA on arterial calcification and the results of some clinical trials.

The Short Overview on the Relevance of Fatty Acids for Human Cardiovascular Disorders

This review presents existing evidence of the influence of saturated and unsaturated fatty acids on cardiovascular diseases (CVD). Data are discussed regarding the roles of the most relevant fatty acids, such as myristic (C14:0), palmitic (C16:0), stearic (C18:0), palmitoleic (C16:1), oleic (C18:1), linoleic (C18:2), α-linolenic (C18:3, ω-3), γ-linolenic (C18:3, ω-6), arachidonic (C20:4), eicosapentaenoic (C20:5), docosahexaenoic (C22:6), and docosapentaenoic (C22:5) acid. The accumulated knowledge has expanded the understanding of the involvement of fatty acids in metabolic processes, thereby enabling the transition from basic exploratory studies to practical issues of application of these biomolecules to CVD treatment. In the future, these findings are expected to facilitate the interpretation and prognosis of changes in metabolic lipid aberrations in CVD.

Predictors of endothelial function improvement in patients with mild hypertriglyceridemia without evidence of coronary artery disease treated with purified eicosapentaenoic acid

BACKGROUND AND AIMS

Eicosapentaenoic acid (EPA) has been reported to reduce cardiovascular risk in patients with hypertriglyceridemia. Although several mechanisms underlying the effects of EPA have been demonstrated, those responsible for its beneficial role in patients with hypertriglyceridemia without evidence of coronary artery disease (CAD) have not been fully elucidated. We sought to clarify the main factors associated with EPA administration that led to improved endothelial function.

METHODS

Forty-seven consecutive patients with mild hypertriglyceridemia (mean age, 59 ± 13 years) without evidence of CAD were prospectively enrolled and administered purified EPA (1800 mg/day). Forty-four patients who were not administered EPA were enrolled as age- and sex-matched controls. Clinical variables and flow-mediated dilation (FMD) were examined before and after 6 months of treatment. Univariate and multivariate regression analyses were performed between FMD changes and clinical variables.

RESULTS

EPA treatment decreased triglyceride levels (from 224.6 ± 58.8 to 151.8 ± 54.5 mg/dl, p < 0.001) and increased FMD (from 4.21% ± 1.91% to 6.21% ± 2.30%, p < 0.001). Multivariate analysis showed that the change in FMD was associated with the baseline high-density lipoprotein cholesterol (HDL-C) level (β = -0.331, p = 0.027) and the change in EPA/arachidonic acid (AA) ratio (β = 0.301, p = 0.048).

CONCLUSIONS

EPA treatment improved triglyceride levels and FMD in patients with mild hypertriglyceridemia and without evidence of CAD. The baseline HDL-C level and the change in EPA/AA ratio predicted FMD improvement. The beneficial effects of EPA on triglyceride-rich lipoproteins and vascular endothelium may help improve endothelial function.

Effect of icosapent ethyl on progression of coronary atherosclerosis in patients with elevated triglycerides on statin therapy: a prospective, placebo-controlled randomized trial (EVAPORATE): interim results

AIMS

Though statin therapy is known to slow coronary atherosclerosis progression and reduce cardiovascular (CV) events, significant CV risk still remains. In the REDUCE-IT study, icosapent ethyl (IPE) added to statin therapy reduced initial CV events by 25% and total CV events by 30%, but its effects on coronary atherosclerosis progression have not yet been fully investigated. Therefore, this study is to determine whether IPE 4 g/day will result in a greater change from baseline in plaque volume measured by serial multidetector computed tomography than placebo in statin-treated patients.

METHODS AND RESULTS

EVAPORATE is a randomized, double-blind, placebo-controlled trial. Patients had to have coronary atherosclerosis by coronary computed tomographic angiography (CCTA) (≥1 angiographic stenoses with ≥20% narrowing), on stable statin therapy with low-density lipoprotein cholesterol levels 40-115 mg/dL, and persistently high triglyceride levels (135-499 mg/dL). Patients underwent an interim scan at 9 months and were followed for an additional 9 months with CCTA at 0, 9, and 18 months. Here, we present the protocol-specified interim efficacy results. A total of 80 patients were enrolled, with 67 completing the 9-month visit and having interpretable CCTA at baseline and at 9 months (age = 57 ± 6 years, male = 36, 63%). At the 9-month interim analysis, there was no significant change in low attenuation plaque (LAP) between active and placebo groups (74% vs. 94%, P = 0.469). However, there was slowing of total non-calcified plaque (sum of LAP, fibrofatty, and fibrous plaque) (35% vs. 43%, P = 0.010), total plaque (non-calcified + calcified plaque) (15% vs. 26%, P = 0.0004), fibrous plaque (17% vs. 40%, P = 0.011), and calcified plaque (-1% vs. 9%, P = 0.001), after adjustment by baseline plaque, age, sex, diabetes, baseline triglyceride levels, and statin use.

CONCLUSION

EVAPORATE is the first study using CCTA to evaluate the effects of IPE as an adjunct to statin therapy on atherosclerotic plaque characteristics in a high-risk CV population with persistently high triglyceride levels. It provides important mechanistic data in regards to the reduction in CV events in the REDUCE-IT clinical trial.

CLINICALTRIALS. GOVIDENTIFIER

NCT029226027.

Eicosapentaenoic acid attenuates renal lipotoxicity by restoring autophagic flux

Recently, we identified a novel mechanism of lipotoxicity in the kidney proximal tubular cells (PTECs); lipid overload stimulates macroautophagy/autophagy for the renovation of plasma and organelle membranes to maintain the integrity of the PTECs. However, this autophagic activation places a burden on the lysosomal system, leading to a downstream suppression of autophagy, which manifests as phospholipid accumulation and inadequate acidification in lysosomes. Here, we investigated whether pharmacological correction by eicosapentaenoic acid (EPA) supplementation could restore autophagic flux and alleviate renal lipotoxicity. EPA supplementation to high-fat diet (HFD)-fed mice reduced several hallmarks of lipotoxicity in the PTECs, such as phospholipid accumulation in the lysosome, mitochondrial dysfunction, inflammation, and fibrosis. In addition to improving the metabolic syndrome, EPA alleviated renal lipotoxicity via several mechanisms. EPA supplementation to HFD-fed mice or the isolated PTECs cultured in palmitic acid (PA) restored lysosomal function with significant improvements in the autophagic flux. The PA-induced redistribution of phospholipids from cellular membranes into lysosomes and the HFD-induced accumulation of SQSTM1/p62 (sequestosome 1), an autophagy substrate, during the temporal and genetic ablation of autophagy were significantly reduced by EPA, indicating that EPA attenuated the HFD-mediated increases in autophagy demand. Moreover, a fatty acid pulse-chase assay revealed that EPA promoted lipid droplet (LD) formation and transfer from LDs to the mitochondria for beta-oxidation. Noteworthy, the efficacy of EPA on lipotoxicity is autophagy-dependent and cell-intrinsic. In conclusion, EPA counteracts lipotoxicity in the proximal tubule by alleviating autophagic numbness, making it potentially suitable as a novel treatment for obesity-related kidney diseases.Abbreviations: 4-HNE: 4-hydroxy-2-nonenal; ACTB: actin beta; ADGRE1/F4/80: adhesion G protein-coupled receptor E1; ATG: autophagy-related; ATP: adenosine triphosphate; BODIPY: boron-dipyrromethene; BSA: bovine serum albumin; cKO: conditional knockout; CML: N-carboxymethyllysine; COL1A1: collagen type I alpha 1 chain; COX: cytochrome c oxidase; CTRL: control; DGAT: diacylglycerol O-acyltransferase; EPA: eicosapentaenoic acid; FA: fatty acid; FFA: free fatty acid; GFP: green fluorescent protein; HFD: high-fat diet; iKO: inducible knockout; IRI: ischemia-reperfusion injury; LAMP1: lysosomal-associated membrane protein 1; LD: lipid droplet; LRP2: low density lipoprotein receptor-related protein 2; MAP1LC3: microtubule-associated protein 1 light chain 3; MTORC1: mechanistic target of rapamycin kinase complex 1; OA: oleic acid; PAS: periodic-acid Schiff; PPAR: peroxisome proliferator activated receptor; PPARGC1/PGC1: peroxisome proliferator activated receptor, gamma, coactivator 1; PTEC: proximal tubular epithelial cell; ROS: reactive oxygen species; RPS6: ribosomal protein S6; SDH: succinate dehydrogenase complex; SFC/MS/MS: supercritical fluid chromatography triple quadrupole mass spectrometry; SQSTM1/p62: sequestosome 1; TFEB: transcription factor EB; TG: triglyceride; TUNEL: terminal deoxynucleotidyl transferase dUTP nick end labeling.

Effects of n-3 PUFA on endothelial function in patients with peripheral arterial disease: a randomised, placebo-controlled, double-blind trial

As only limited evidence is available for potential benefits of n-3 PUFA supplementation in patients with peripheral arterial disease (PAD), we studied the effects of 4 g n-3 PUFA on endothelial function and inflammatory markers. Seventy patients with stable PAD classified as Rutherford stage 2 or 3 and good control of cardiovascular factors were randomised to receive either 4 g n-3 PUFA or placebo daily for 3 months in a double-blind fashion. Primary endpoint was endothelial function assessed by flow-mediated vasodilation (FMD). In addition, ankle-brachial index, maximum and pain-free walking distances were determined. Lipid parameters including the omega-3 index reflecting n-3 PUFA intake as well as pro-inflammatory, endothelial and platelet activation markers were measured over the same time interval. After 3 months of treatment with 4 g n-3 PUFA daily, a significant improvement of FMD was observed compared with placebo (n-3 PUFA, median Δ 3·7 (interquartile range (IQR) -1·8, 7·1) % v. placebo, Δ -0·5 (IQR -6·5, 3·0) %, P = 0·01 between the groups). After a 3-month washout period, this benefit was not sustained (n-3 PUFA, median Δ 0·6 (IQR -2·2, 5·6) % v. placebo, Δ -0·9 (IQR -6·6, 6·7) %, P = 0·20). In response to n-3 PUFA, an improvement of lipid parameters with a pronounced increase in the omega-3 index was seen. No changes were found for other parameters. In conclusion, in patients with PAD, 4 g/d n-3 PUFA improved cardiovascular risk in PAD patients, which needs testing in large-scale trials.