Association between ratio of serum eicosapentaenoic acid to arachidonic acid and risk of cardiovascular disease: the Hisayama Study

Association of Omega-3 Polyunsaturated Fatty Acids with Sarcopenia in Liver Cirrhosis Patients with Hepatocellular Carcinoma

Background and Aims

Sarcopenia is associated with the prognosis of patients with liver cirrhosis and hepatocellular carcinoma (HCC). Given their diverse physiological activities, we hypothesized that plasma fatty acids might influence the progression of sarcopenia. This study aimed to clarify the association between fatty acids and sarcopenia in cirrhotic patients with HCC.

Methods

In this single-center retrospective study, we registered 516 cases and analyzed 414 cases of liver cirrhosis and HCC. The skeletal muscle mass index was measured using a transverse computed tomography scan image at the third lumbar vertebra. The cutoff value for sarcopenia followed the criteria set by the Japan Society of Hepatology. Fatty acid concentrations were measured by gas chromatography.

Results

Fatty acid levels, particularly omega-3 (n-3) polyunsaturated fatty acid (PUFA), were lower in patients with poor liver function (Child-Pugh grade B/C) and were negatively correlated with the albumin-bilirubin score (p<0.0001). The prognosis of HCC patients with low PUFA levels was significantly worse. Among the different fatty acid fractions, only n-3 PUFAs significantly correlated with skeletal muscle mass index (p=0.0026). In the multivariate analysis, the n-3 PUFA level was an independent variable associated with sarcopenia (p=0.0006).

Conclusions

A low level of n-3 PUFAs was associated with sarcopenia in patients with liver cirrhosis and HCC.

A Cross-Sectional Pilot Study on Association of Ready-to-Eat and Processed Food Intakes with Metabolic Factors, Serum Trans Fat and Phospholipid Fatty Acid Compositions in Healthy Japanese Adults

Frequently consuming processed and ready-to-eat (RTE) foods is regarded as unhealthy, but evidence on the relationships with circulating metabolic parameters is lacking. Japanese residents of a metropolitan area, 20 to 50 years of age, were studied in terms of anthropometric and biochemical parameters, including circulating trans fat and serum phospholipid fatty acid levels. Processed foods, except drinks and dairy items, were categorized according to requirements for additional ingredients and cooking before eating. Processed and RTE foods were divided according to fat and/or oil content into non-fatty or fatty foods. The participants were grouped into tertiles based on the energy percent (En%) derived from fatty-RTE foods. Fatty-RTE En% showed negative associations with fish, soybean and soybean products, dairy, eggs, vegetables, seaweed/mushrooms/konjac, fruit and non-oily seasonings reflecting lower dietary fiber, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and mineral and vitamin intakes, while the associations with fat/oil, confectionaries, and sweet beverages were positive. Fatty-RTE En% consumption was positively associated with alkaline phosphatase, leucine aminopeptidase, direct bilirubin, elaidic acid, and C18:2 but inversely associated with HDL cholesterol, C15:0, C17:0, EPA, and DHA. A higher fatty-RTE food intake was suggested to contribute to unbalanced nutrient intakes, as reflected in lipid metabolic parameters. Further large-scale studies are needed to evaluate the quality and impacts of RTE foods.

Omega-3 Blood Levels and Stroke Risk: A Pooled and Harmonized Analysis of 183 291 Participants From 29 Prospective Studies

BACKGROUND

The effect of marine omega-3 PUFAs on risk of stroke remains unclear.

METHODS

We investigated the associations between circulating and tissue omega-3 PUFA levels and incident stroke (total, ischemic, and hemorrhagic) in 29 international prospective cohorts. Each site conducted a de novo individual-level analysis using a prespecified analytical protocol with defined exposures, covariates, analytical methods, and outcomes; the harmonized data from the studies were then centrally pooled. Multivariable-adjusted HRs and 95% CIs across omega-3 PUFA quintiles were computed for each stroke outcome.

RESULTS

Among 183 291 study participants, there were 10 561 total strokes, 8220 ischemic strokes, and 1142 hemorrhagic strokes recorded over a median of 14.3 years follow-up. For eicosapentaenoic acid, comparing quintile 5 (Q5, highest) with quintile 1 (Q1, lowest), total stroke incidence was 17% lower (HR, 0.83 [CI, 0.76-0.91]; P<0.0001), and ischemic stroke was 18% lower (HR, 0.82 [CI, 0.74-0.91]; P<0.0001). For docosahexaenoic acid, comparing Q5 with Q1, there was a 12% lower incidence of total stroke (HR, 0.88 [CI, 0.81-0.96]; P=0.0001) and a 14% lower incidence of ischemic stroke (HR, 0.86 [CI, 0.78-0.95]; P=0.0001). Neither eicosapentaenoic acid nor docosahexaenoic acid was associated with a risk for hemorrhagic stroke. These associations were not modified by either baseline history of AF or prevalent CVD.

CONCLUSIONS

Higher omega-3 PUFA levels are associated with lower risks of total and ischemic stroke but have no association with hemorrhagic stroke.

Enhanced Production of EPA-Derived Anti-Inflammatory Metabolites after Oral Administration of a Novel Self-Emulsifying Highly Purified EPA Ethyl Ester Formulation (MND-2119)

AIMS

MND-2119 is a novel once-daily dose self-emulsifying formulation of highly purified eicosapentaenoic acid ethyl ester (EPA-E) and is approved as an antihyperlipidemia agent in Japan. It has improved absorption and achieves higher plasma EPA concentrations at Cmax than conventional EPA-E. In the JELIS trial, concomitant use of EPA-E with statin therapy significantly reduced atherosclerotic cardiovascular disease (ASCVD) risks. As a potential mechanism of action of EPA, endogenous formation of EPA-derived anti-inflammatory metabolites is receiving greater attention. This study aims to investigate the endogenous formation of EPA-derived anti-inflammatory metabolites following single and multiple administrations of MND-2119.

METHODS

Healthy adult male subjects were randomly assigned to a nonintervention (control) group, MND-2119 2-g/day group, MND-2119 4-g/day group, or EPA-E 1.8-g/day group for 7 days (N=8 per group). Plasma fatty acids and EPA-derived metabolites were evaluated. Peripheral blood neutrophils were isolated, and the production of EPA-derived metabolites from in vitro stimulated neutrophils was evaluated.

RESULTS

After single and multiple administrations of MND-2119 2 g/day, there were significant increases in plasma EPA concentration, 18-hydroxyeicosapentaenoic acid (18-HEPE), and 17,18-epoxyeicosatetraenoic acid compared with those of EPA-E 1.8 g/day. They were further increased with MND-2119 4 g/day administration. In neutrophils, the EPA concentration in the MND-2119 2-g/day group was significantly higher compared with that in the EPA-E 1.8-g/day group after multiple administration, and 18-HEPE production was positively correlated with EPA concentration. No safety issues were noted.

CONCLUSIONS

These results demonstrate that MND-2119 increases the plasma and cellular concentrations of EPA and EPA-derived metabolites to a greater extent than conventional EPA-E formulations.

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.

Distinct associations between dietary omega-3 and omega-6 fatty acids intake with chronic kidney disease in adults with and without diabetes: A cross-sectional study

OBJECTIVE

We explored the relationship of dietary intake of fatty acids with chronic kidney disease (CKD) according to glycemic status in Japanese people.

METHODS

A total of 1031 participants aged ≥40 y were included in this population-based, cross-sectional study. A validated self-administered diet history questionnaire was used to measure the dietary intakes of fat and fatty acids, including omega-3 and omega-6 polyunsaturated fatty acids. CKD was defined as estimated glomerular filtration rate < 60 mL/min/1.73 m2 and diabetes as the use of antidiabetic medication, fasting plasma glucose ≥ 126 mg/dL, or hemoglobin A1c of ≥6.5%. Urine biomarkers of kidney injury (liver-type fatty acid-binding protein, β2-microglobulin, and albumin) were also examined.

RESULTS

The mean age of the participants was 62.5 ± 11.2 y, and 482 (46.8%) of them were men. Overall, 177 (17.2%) participants had CKD. In the multivariable model, low omega-3 intake (odds ratio = 0.109; 95% CI, 0.019-0.645) and high omega-6-to-omega-3 ratio (odds ratio = 2.112; 95% CI, 1.167-3.822) were associated with CKD in participants with diabetes but not in those without. In selected participants with diabetes, a substantial trend of urinary liver-type fatty acid-binding protein and β2-microglobulin level elevation along with an increase in the dietary ratio of omega-6 to omega-3 was observed.

CONCLUSIONS

Low dietary omega-3 intake and high omega-6-to-omega-3 ratio were associated with CKD in middle-aged and older Japanese people with diabetes but not in those without diabetes. These results may provide insight into the more tailored approaches for dietary polyunsaturated fatty acids to prevent CKD.

Association between Eicosapentaenoic Acid to Arachidonic Acid Ratio and Characteristics of Plaque Rupture

AIMS

Eicosapentaenoic acid (EPA) has shown beneficial effects on coronary plaque stabilization. Based on our previous study, we speculated that EPA might be associated with the development of healed plaques and might limit thrombus size. This study aimed to elucidate the association between EPA and arachidonic acid (AA) ratios and various plaque characteristics in patients with plaque rupture.

METHODS

A total of 95 patients with acute coronary syndrome (ACS) caused by plaque rupture who did not take lipid-lowering drugs and underwent percutaneous coronary intervention using optical coherence tomography (OCT) were included. Clinical characteristics, lipid profiles, and OCT findings were compared between patients with lower and higher EPA/AA ratios (0.41) according to the levels in the Japanese general population.

RESULTS

In the high EPA/AA (n=29, 30.5%) and low EPA/AA (n=66, 69.5 %) groups, the high EPA/AA group was significantly older (76.1 vs. 66.1 years, P＜0.01) and had lower peak creatine kinase (556 vs. 1651 U/L, P=0.03) than those with low EPA/AA. Similarly, patients with high EPA/AA had higher prevalence of layered and calcified plaque (75.9 vs. 39.4 %, P＜0.01; 79.3 vs. 50.0 %, P＜0.01, respectively) than low EPA/AA group. Multivariate logistic regression analysis demonstrated that a high EPA/AA ratio was an independent factor in determining the development of layered and calcified plaques.

CONCLUSION

A high EPA/AA ratio may be associated with the development of layered and calcified plaques in patients with plaque rupture.

Triglycerides revisited: is hypertriglyceridaemia a necessary therapeutic target in cardiovascular disease?

Despite the atherosclerotic cardiovascular disease (ASCVD) risk reduction achieved by low-density lipoprotein cholesterol (LDL-C) lowering therapy, residual ASCVD risk still exists. Previous epidemiological studies have suggested high plasma triglyceride (TG) levels as a risk factor or risk marker for ASCVD independent of LDL-C levels. In this review, we highlighted the underlying pathophysiology of hypertriglyceridaemia, the mechanistic action of therapeutic agents, the interpretation of conflicting results on recent clinical trials, and the present options for primary and secondary prevention. The benefits of fibrates-induced reduction in TG and increase in high-density lipoprotein cholesterol might outweigh the disadvantages of increasing LDL-C levels in primary prevention. In secondary CVD prevention, using eicosapentaenoic acid without docosahexaenoic acid, in addition to statins, will be beneficial. This comprehensive review may prove useful for the development of novel approaches that target hypertriglyceridaemia in future.

Placental AA/EPA Ratio Is Associated with Obesity Risk Parameters in the Offspring at 6 Years of Age

During pregnancy, maternal polyunsaturated fatty acids (PUFA) are transferred to the fetus through the placenta by specific FA transporters (FATP). A higher perinatal exposure to n-6 over n-3 PUFA could be linked to excess fat mass and obesity development later in life. In this context, we aimed to assess the associations between long chain PUFAs (LC-PUFAs) (n-6, n-3, and n-6/n-3 ratios) measured in the placenta at term birth with obesity-related parameters in the offspring at 6 years of age and assess whether these associations are dependent on the placental relative expression of fatty acid transporters. As results, the PUFAn-6/PUFAn-3 ratio was 4/1, which scaled up to 15/1 when considering only the arachidonic acid/eicosapentaenoic acid ratio (AA/EPA ratio). Positive associations between the AA/EPA ratio and offspring's obesity risk parameters were found with weight-SDS, BMI-SDS, percent fat mass-SDS, visceral fat, and HOMA-IR (r from 0.204 to 0.375; all p < 0.05). These associations were more noticeable in those subjects with higher expression of fatty acid transporters. Therefore, in conclusion, a higher placental AA/EPA ratio is positively associated with offspring's visceral adiposity and obesity risk parameters, which become more apparent in subjects with higher expressions of placental FATPs. Our results support the potential role of n-6 and n-3 LC-PUFA in the fetal programming of obesity risk in childhood. For the present study, 113 healthy pregnant women were recruited during the first trimester of pregnancy and their offspring were followed up at 6 years of age. The fatty acid profiles and the expression of fatty acid transporters (FATP1 and FATP4) were analyzed from placental samples at birth. Associations between LC-PUFA (n-6, n-3, and n-6/n-3 ratios) and obesity risk parameters (weight, body mass index (BMI), percent fat mass, visceral fat, and homeostatic model assessment of insulin resistance (HOMA-IR)) in the offspring at 6 years of age were examined.

Study protocol and baseline characteristics of Randomized trial for Evaluation in Secondary Prevention Efficacy of Combination Therapy-Statin and Eicosapentaenoic Acid: RESPECT-EPA, the combination of a randomized control trial and an observational biomarker study

BACKGROUND

Omega-3 polyunsaturated fatty acids (PUFAs) have been a hot topic since the Japan EPA Lipid Intervention Study (JELIS), the first landmark study using a highly purified eicosapentaenoic acid (EPA), indicated that EPA could decrease the incidence of cardiovascular events. Over 20 years have passed since the JELIS was conducted, and the standard treatment for dyslipidemia has altered significantly since then. The JELIS subjects did not undertake the current risk management especially current standard statins and did not exclusively target secondary prevention patients. In addition, the subjects included are relatively high EPA population. Furthermore, the clinical implication of the plasma EPA/arachidonic acid (AA) ratio as a biomarker has not yet been validated. Therefore, the Randomized trial for Evaluation in Secondary Prevention Efficacy of Combination Therapy - Statin and EPA (RESPECT-EPA) was planned and is currently underway in Japan.

METHODS

The RESPECT-EPA comprises two parts: the open-label randomized controlled trial (RCT) and biomarker study (prospective cohort study design). The RCT included patients with a low EPA/AA ratio. These patients were then randomized to highly purified EPA (1800 mg/day) or control groups. The primary endpoint was cardiovascular death, non-fatal myocardial infarction, non-fatal ischemic stroke, unstable angina pectoris, and clinically indicated coronary revascularization. The biomarker study assesses the EPA/AA ratio's usefulness as a biomarker for cardiovascular events prediction.

RESULTS

In the RCT, a total of 2,460 patients were enrolled in 95 sites in Japan. Patients' baseline characteristics were similar between intervention and control groups in the RCT. The baseline median EPA/AA ratio was 0.243 and 0.235, respectively. A total of 1,314 patients were participated in the observational part, and the baseline median EPA/AA ratio was 0.577.

CONCLUSIONS

After this study is completed, we will have further evidence on whether a highly purified EPA is effective in reducing cardiovascular events for secondary prevention or not, as well as whether if EPA/AA ratio is a predictor for future cardiovascular events. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN000012069).

Omega-3 Fatty Acids in Cardiovascular Disease and Diabetes: a Review of Recent Evidence

PURPOSE OF REVIEW

Omega-3 fatty acids (n-3 FA) lower triglycerides, have anti-inflammatory properties, and improve metabolism. Clinical evidence of cardiovascular benefit with omega-3 fatty acids is mixed. We discuss mechanisms providing biological plausibility of benefit of omega-3 fatty acids in cardiovascular risk reduction and review clinical trials investigating the benefits of prescription omega-3 fatty acids in dyslipidemia, atherosclerotic cardiovascular disease (ASCVD), and diabetes.

RECENT FINDINGS

Although early trials showed no benefit of omega-3 fatty acids in ASCVD, the REDUCE-IT trial noted significant risk reduction in ASCVD events with highly purified EPA (icosapent ethyl) use which has changed the landscape for currently available therapeutic options. However, other large trials like STRENGTH and VITAL, which used different formulations of prescription omega-3 fatty acids, did not note significant cardiovascular risk reduction. Thus the effectiveness of omega-3 fatty acids for cardiovascular disease prevention is an ongoing topic of debate. A relative paucity of studies examining benefits for glycemic outcomes in persons with diabetes exists; however, few studies have suggested lack of benefit to date. Significant residual cardiovascular risk exists for individuals with hypertriglyceridemia. Prescription omega-3 fatty acids are more commonly used for CV risk reduction in these patients. Clinical guideline statements now recommend icosapent ethyl use for selected individuals with hypertriglyceridemia to reduce cardiovascular events given recent evidence from the REDUCE-IT trial. Nonetheless, data from other large scale trials has been mixed, and future research is needed to better understand how different preparations of omega-3 may differ in their cardiovascular and metabolic effects, and the mechanisms for their benefit.

Polyunsaturated ω3 fatty acids prevent the cardiac hypertrophy in hypertensive rats

It has been demonstrated that supplementation with the two main omega 3 polyunsaturated fatty acids (ω3 FAs), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA), leads to modifications in the cardiac physiology. ω3 FAs can affect the membrane's lipid composition, as well as proteins' location and/or function. The Na⁺/H⁺ exchanger (NHE1) is an integral membrane protein involved in the maintenance of intracellular pH and its hyperactivity has been associated with the development of various cardiovascular diseases such as cardiac hypertrophy. Our aim was to determine the effect of ω3 FAs on systolic blood pressure (SBP), lipid profiles, NHE1 activity, and cardiac function in spontaneously hypertensive rats (SHR) using Wistar rats (W) as normotensive control. After weaning, the rats received orally ω3 FAs (200 mg/kg body mass/day/ 4 months). We measured SBP, lipid profiles, and different echocardiography parameters, which were used to calculate cardiac hypertrophy index, systolic function, and ventricular geometry. The rats were sacrificed, and ventricular cardiomyocytes were obtained to measure NHE1 activity. While the treatment with ω3 FAs did not affect the SBP, lipid analysis of plasma revealed a significant decrease in omega-6/omega-3 ratio, correlated with a significant reduction in left ventricular mass index in SHR. The NHE1 activity was significantly higher in SHR compared with W. While in W the NHE1 activity was similar in both groups, a significant decrease in NHE1 activity was detected in SHRs supplemented with ω3 FAs, reaching values comparable with W. Altogether, these findings revealed that diet supplementation with ω3 FAs since early age prevents the development of cardiac hypertrophy in SHR, perhaps by decreasing NHE1 activity, without altering hemodynamic overload.

Genetic deletion of Cyp4f18 disrupts the omega-3 epoxidation pathway and results in psoriasis-like dermatitis

Cyp4f18 catalyzes the conversion of n-3 polyunsaturated fatty acids (PUFAs) into omega-3 epoxides, such as 17,18-epoxyeicosatetraenoic acid (17,18-EpETE) and 19,20-epoxydocosapentaenoic acid (19,20-EpDPE) from eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), respectively. Cyp4f18-deficient mice spontaneously develop psoriasis-like dermatitis. A significant increase in the number of IL-17A-positive gamma delta (γδ) T cells in the skin and enlargement of draining lymph nodes was observed. These symptoms were drastically suppressed by antibiotic treatment. Cyp4f18 is highly expressed in dendritic cells (DCs), and Cyp4f18-deficient bone marrow-derived dendritic cells (BMDCs) show markedly increased expression levels of cytokines such as IL-23 and IL-1β in response to lipopolysaccharide (LPS) stimulation. Lipidomic analysis of lymph nodes and BMDCs revealed a significant decrease in a series of omega-3 epoxidized metabolites. Among them, 17,18-dihydroxyeicosatetraenoic acid (17,18-diHETE), a vicinal diol derived from EPA omega-3 epoxidation suppressed IL-23 production in LPS-stimulated BMDCs in Cyp4f18-deficient mice. These results demonstrate that Cyp4f18 endogenously produces omega-3-epoxidized metabolites in the draining lymph nodes, and these metabolites contribute to skin homeostasis by suppressing the excessive activation of the IL-23/IL-17 axis initiated by DCs.

Association between the ratio of serum eicosapentaenoic acid to arachidonic acid and risk of coronary artery disease in young Chinese patients

Objective

Long-chain (LC) omega-3 PUFAs, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may play an anti-inflammatory effect and decrease the risk of coronary artery disease (CAD). In contrast, omega-6 PUFA, mainly arachidonic acid (AA), has pro-inflammatory and pro-aggregatory effects, which may increase the risk of CAD. This study evaluated the associations between EPA, DHA, AA, and their ratios (EPA/AA and DHA/AA) with the risk of CAD in young Chinese patients.

Methods

A total of 182 young patients with CAD and 143 age-matched controls were included. Traditional cardiovascular risk factors were recorded. Serum EPA, DHA and AA were measured by ultra-performance liquid chromatography-mass spectrometry.

Results

The level of AA was significantly higher, while the level of EPA was lower in the CAD group than that in the control group. There was no significant difference in DHA level in the two groups. Both the ratios of EPA/AA and DHA/AA were lower in the CAD group than that in the control. Multivariate logistic regression analysis showed that higher serum AA level was associated with the increased risk of CAD, while EPA was a protective factor for CAD. There was no significant association between DHA level and the risk of CAD. Although both higher ratios of EPA/AA [per tertile increment, adjusted odds ratios (ORs) (OR) 0.356, 95% confidence intervals (CI) 0.247–0.513] and DHA/AA (adjusted OR = 0.465, 95%CI = 0.332–0.653) were associated with a lower risk of CAD in young patients. Receiver operating characteristic (ROC) curve analysis showed that compared with AA, the diagnostic value was increased in EPA/AA, but not in DHA/AA.

Conclusion

EPA, but not DHA may play a protective role in CAD, while AA may be associated with the increased risk of CAD in young Chinese patients. The ratio of EPA/AA can increase the predictive value for diagnosing CAD than EPA or AA alone.

Walnut supplementation after fructose-rich diet is associated with a beneficial fatty acid ratio and increased ACE2 expression in the rat heart

Increased fructose consumption has been linked with chronic inflammation and metabolic syndrome (MetS). Activation of the renin-angiotensin system (RAS) and NF-κB have been detected in MetS. Walnuts are a rich source of polyunsaturated omega-3 fatty acids (n-3 PUFA) that were suggested to exert anti-inflammatory effects related to cardio-metabolic health. We hypothesized that walnut supplementation has the capacity to revert unfavorable fructose-rich diet (FRD)-induced activation of cardiac RAS and NF-κB in male rats. Due to the lack of similar studies, we investigated the effects of walnut supplementation (6 weeks) on the expression of four RAS molecules (ACE, ACE2, AT1R, and AT2R) and NF-κB in rat heart after FRD (10% w/v, 9 weeks). In addition, we followed the changes in the n-6/n-3 PUFA ratio in the total pool of heart lipids after both treatments to elucidate the walnut effects on fatty acids in the heart. 36 animals (9 per group) participated in the experiment. FRD significantly increased the ACE protein level in the heart (p &lt; 0.001). Walnut supplementation significantly increased the ACE2 protein level in the heart of FRD (p &lt; 0.001). In addition, walnut supplementation showed a significant main effect on the arachidonic acid/eicosapentaenoic acid ratio (p = 0.004). Walnut supplementation significantly reduced this ratio, in comparison with both, the control group (C vs. FW, p &lt; 0.05) and the FRD group (F vs. FW, p &lt; 0.05). However, walnut treatment failed to revert the significant effect of fructose (p &lt; 0.001) on the elevation of NF-κB protein level. Our results suggest a beneficial effect of walnut supplementation on ACE2 protein level and n-6/n-3 PUFA level in the heart of the animal model of MetS. Such results highlight the approach of omega-3-rich walnut supplementation in the stimulation of endogenous production of favorable molecules in the heart which could be an affordable nutritional treatment formaintenance of cardio-metabolic health.

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.

Associations of erythrocyte polyunsaturated fatty acids with incidence of stroke and stroke types in adult Chinese: a prospective study of over 8000 individuals

PURPOSE

There is limited and inconsistent evidence about the relationships of erythrocyte polyunsaturated fatty acids (PUFAs) with stroke and stroke types, particularly in China where the stroke rates are high. We aimed to investigate the associations of different erythrocyte PUFAs with incidence of total stroke, ischemic stroke (IS), and intracerebral hemorrhage (ICH) in Chinese adults.

METHODS

In the prospective China Kadoorie Biobank, erythrocyte PUFAs were measured using gas chromatography in 10,563 participants who attended 2013-14 resurvey. After a mean follow-up of 3.8 years, 412 incident stroke cases (342 IS, 53 ICH) were recorded among 8,159 participants without prior vascular diseases or diabetes. Cox regression yielded adjusted hazard ratios (HRs) for stroke associated with 13 PUFAs.

RESULTS

Overall, the mean body mass index was 24.0 (3.4) kg/m² and the mean age was 58.1 (9.9) years. In multivariable analyses, 18:2n-6 was positively associated with ICH (HR = 2.33 [95% CIs 1.41, 3.82] for top versus bottom quintile, P_trend = 0.007), but inversely associated with IS (0.69 [0.53,0.90], P_trend = 0.027), while 20:3n-6 was positively associated with risk of IS (1.64 [1.32,2.04], P_trend < 0.001), but not with ICH. Inverted-U shape curve associations were observed of 20:5n-3 with IS (P_nonlinear = 0.002) and total stroke (P_nonlinear = 0.008), with a threshold at 0.70%. After further adjustment for conventional CVD risk factors and dietary factors, these associations remained similar.

CONCLUSION

Among relatively lean Chinese adults, erythrocyte PUFAs 18:2n-6, 20:3n-6 and 20:5n-3 showed different associations with risks of IS and ICH. These results would improve the understanding of stroke etiology.

Eicosapentaenoic acid/arachidonic acid ratio in Japanese junior high school students

BACKGROUND

This epidemiological study investigated the eicosapentaenoic acid/arachidonic acid ratio (EAR) and docosahexaenoic acid/ arachidonic acid ratio (DAR) in ninth-graders in Japan.

METHODS

A total of 175 ninth-grade children from Tsunan Town (115 boys and 60 girls) were enrolled in the study between 2015 and 2017. All participants were assessed during annual health checkups to determine their EAR and DAR. All data were compared between boys and girls using the Mann-Whitney test. Spearman's rank correlation coefficient was used to describe the strengths of correlations between the EAR, DAR, and relevant parameters.

RESULTS

The median (minimum, maximum) EAR and DAR of all participants were 0.13 (0.05, 0.46) and 0.47 (0.25, 0.84), respectively. There was no significant difference in the EAR between boys and girls at 0.12 (0.05, 0.46) and 0.13 (0.06, 0.27) (P = 0.375), respectively. The DAR was not significantly different (P = 0.125). There was a significant positive correlation between EAR and triglyceride, body mass index, and homeostasis model assessment but a significantly negative correlation with HbA1c (r = -0.209, P = 0.006). In contrast, there was no significant correlation between DAR and any parameters.

CONCLUSIONS

This is the first epidemiological study investigating the EAR using a population-based cohort of Japanese adolescents. The EAR in boys/girls in Japan is 0.12 (0.05, 0.46)/0.13 (0.06, 0.27). The study results suggest that children with a healthy diet may generally have a lower average blood glucose level.

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.

Krill-Oil-Dependent Increases in HS-Omega-3 Index, Plasma Choline and Antioxidant Capacity in Well-Conditioned Power Training Athletes

There is evidence that both omega-3 polyunsaturated fatty acids (n-3 PUFAs) and choline can influence sports performance, but information establishing their combined effects when given in the form of krill oil during power training protocols is missing. The purpose of this study was therefore to characterize n-3 PUFA and choline profiles after a one-hour period of high-intensity physical workout after 12 weeks of supplementation. Thirty-five healthy power training athletes received either 2.5 g/day of Neptune krill oil^TM (550 mg EPA/DHA and 150 mg choline) or olive oil (placebo) in a randomized double-blind design. After 12 weeks, only the krill oil group showed a significant HS-Omega-3 Index increase from 4.82 to 6.77% and a reduction in the ARA/EPA ratio (from 50.72 to 13.61%) (p < 0.001). The krill oil group showed significantly higher recovery of choline concentrations relative to the placebo group from the end of the first to the beginning of the second exercise test (p = 0.04) and an 8% decrease in total antioxidant capacity post-exercise versus 21% in the placebo group (p = 0.35). In conclusion, krill oil can be used as a nutritional strategy for increasing the HS-Omega-3 Index, recover choline concentrations and address oxidative stress after intense power trainings.

Molecular Immune-Inflammatory Connections between Dietary Fats and Atherosclerotic Cardiovascular Disease: Which Translation into Clinics?

Current guidelines recommend reducing the daily intake of dietary fats for the prevention of ischemic cardiovascular diseases (CVDs). Avoiding saturated fats while increasing the intake of mono- or polyunsaturated fatty acids has been for long time the cornerstone of dietary approaches in cardiovascular prevention, mainly due to the metabolic effects of these molecules. However, recently, this approach has been critically revised. The experimental evidence, in fact, supports the concept that the pro- or anti-inflammatory potential of different dietary fats contributes to atherogenic or anti-atherogenic cellular and molecular processes beyond (or in addition to) their metabolic effects. All these aspects are hardly translatable into clinics when trying to find connections between the pro-/anti-inflammatory potential of dietary lipids and their effects on CVD outcomes. Interventional trials, although providing stronger potential for causal inference, are typically small sample-sized, and they have short follow-up, noncompliance, and high attrition rates. Besides, observational studies are confounded by a number of variables and the quantification of dietary intakes is far from optimal. A better understanding of the anatomic and physiological barriers for the absorption and the players involved in the metabolism of dietary lipids (e.g., gut microbiota) might be an alternative strategy in the attempt to provide a first step towards a personalized dietary approach in CVD prevention.

Improved fatty acid profile reduces body fat and arterial stiffness in obese adolescents upon combinatorial intervention with exercise and dietary restriction

Objective

In order to examine the effect of 4-week combinatorial intervention with exercise training and dietary restriction on serum fatty acids, and to explore the correlation of intervention-induced improvement of serum fatty acid profile with the reduction of body fat and arterial stiffness.

Methods

Thirty-three obese adolescents were randomized into the intervention (n = 19) and control (n = 14) groups. The participants from the intervention group were subjected to 4-week combinatorial intervention with exercise training and dietary restriction while the participants from the control group maintained regular activities and diet habits. Anthropometry, serum fatty acids and arterial stiffness were measured before and after 4-week intervention.

Results

The participants upon combinatorial intervention revealed the improved body compositions and serum fatty acid profile, and reduced arterial stiffness when compared with their basal levels and the control participants (p < 0.05). Moreover, the decrease in myristic acid, stearic acid, arachidic acid, behenic acid, palmitoleic acid, and dihomo-γ-linolenic acid, was associated with the reduction in body fat. A positive correlation between arachidonic acid and left brachial ankle pulse velocity was observed, and the increase in docosahexaenoic acid was associated with the reduction of left brachial ankle pulse wave velocity and the enhancement of right ankle brachial index.

Conclusion

The 4-week combinatorial intervention is a useful strategy to improve serum fatty acid profile along with the reduction of body fat and arterial stiffness in obese adolescents.

Walnut Supplementation Restores the SIRT1-FoxO3a-MnSOD/Catalase Axis in the Heart, Promotes an Anti-Inflammatory Fatty Acid Profile in Plasma, and Lowers Blood Pressure on Fructose-Rich Diet

The benefits of walnut (Juglans regia) consumption for metabolic health are known, but the molecular background underlying their putative antioxidant and anti-inflammatory/immunomodulatory effects is underexplored. We assessed that walnut supplementation (6 weeks) reverted unfavorable changes of the SIRT1/FoxO3a/MnSOD/catalase axis in the heart induced by fructose-rich diet (FRD). Intriguingly, Nox4 was increased by both FRD and walnut supplementation. FRD increased the cytosolic fraction and decreased the nuclear fraction of the uniquely elucidated ChREBP in the heart. The ChREBP nuclear fraction was decreased in control rats subjected to walnuts. In addition, walnut consumption was associated with a reduction in systolic BP in FRD and a decrease in fatty acid AA/EPA and AA/DHA ratios in plasma. In summary, the protective effect of walnut supplementation was detected in male rats following the fructose-induced decrease in antioxidative/anti-inflammatory capacity of cardiac tissue and increase in plasma predictors of low-grade inflammation. The current results provide a novel insight into the relationship between nutrients, cellular energy homeostasis, and the modulators of inflammatory/immune response in metabolic syndrome, emphasizing the heart and highlighting a track for translation into nutrition and dietary therapeutic approaches against metabolic disease.

Maternal diet high in linoleic acid alters offspring fatty acids and cardiovascular function in a rat model

Linoleic acid (LA), an essential n-6 fatty acid (FA), is critical for fetal development. We investigated the effects of maternal high LA (HLA) diet on offspring cardiac development and its relationship to circulating FA and cardiovascular function in adolescent offspring, and the ability of the postnatal diet to reverse any adverse effects. Female Wistar Kyoto rats were fed low LA (LLA; 1·44 % energy from LA) or high LA (HLA; 6·21 % energy from LA) diets for 10 weeks before pregnancy and during gestation/lactation. Offspring, weaned at postnatal day 25, were fed LLA or HLA diets and euthanised at postnatal day 40 (n 6-8). Maternal HLA diet decreased circulating total cholesterol and HDL-cholesterol in females and decreased total plasma n-3 FA in males, while maternal and postnatal HLA diets decreased total plasma n-3 FA in females. α-Linolenic acid (ALA) and EPA were decreased by postnatal but not maternal HLA diets in both sexes. Maternal and postnatal HLA diets increased total plasma n-6 and LA, and a maternal HLA diet increased circulating leptin, in both male and female offspring. Maternal HLA decreased slopes of systolic and diastolic pressure-volume relationship (PVR), and increased cardiac Col1a1, Col3a1, Atp2a1 and Notch1 in males. Maternal and postnatal HLA diets left-shifted the diastolic PVR in female offspring. Coronary reactivity was altered in females, with differential effects on flow repayment after occlusion. Thus, maternal HLA diets impact lipids, FA and cardiac function in offspring, with postnatal diet modifying FA and cardiac function in the female offspring.

Low circulating arachidonic acid is associated with macroalbuminuria in diabetic patients: a cross-sectional examination of the KAMOGAWA-DM cohort study

BACKGROUND

Diabetic nephropathy, a major complication of diabetes, is the primary risk factor for dialysis, cardiovascular diseases, and mortality. Dietary fatty acids (FAs) have been revealed to be related with cardiovascular diseases in the general populations. The aim of this study was to investigate the association of circulating FAs with diabetic nephropathy.

METHODS

In this cross-sectional study, 190 Japanese patients with type 2 diabetes were included. Circulating FAs were measured by gas chromatography-mass spectrometry. Spearman rank correlation coefficients were used to investigate the association between the logarithm of FAs and the logarithm of urinary albumin excretion (UAE). We have performed logistic regression analysis to determine the effect of FAs on the presence of macroalbuminuria, defined as UAE value ≥300 mg/g creatinine.

RESULTS

Mean age, body mass index, and duration of diabetes were 62.7 ± 12.1 years, 25.0 ± 4.5 kg/m², and 9.8 ± 8.7 years, respectively. In total, 26 patients were diagnosed with macroalbuminuria. The logarithm of circulating arachidonic acid (AA) was negatively associated with the logarithm of UAE (r = - 0.221, p = 0.002). Additionally, circulating AA in patients with macroalbuminuria was lower than that in patients without macroalbuminuria (112.3 ± 75.3 mg/day vs. 164.8 ± 66.0 mg/day, p <  0.001). The logarithm of circulating AA was associated with the presence of macroalbuminuria after adjusting for covariates (odds ratio of Δ1 incremental: 0.32, 95% confidence interval: 0.10-0.99, p = 0.042).

CONCLUSIONS

Circulating AA was negatively associated with UAE and the presence of macroalbuminuria.

Serum metabolite profiling of a 4-Nitroquinoline-1-oxide-induced experimental oral carcinogenesis model using gas chromatography-mass spectrometry

Background

Oral cancer progresses from hyperplastic epithelial lesions through dysplasia to invasive carcinoma. The critical needs in oral cancer treatment are expanding our knowledge of malignant tumour progression and the development of useful approaches to prevent dysplastic lesions. This study was designed to gain insights into the underlying metabolic transformations that occur during the process of oral carcinogenesis.

Methods

We used gas chromatography-mass spectrometry (GC-MS) in conjunction with multivariate statistical techniques to observe alterations in serum metabolites in a 4-Nitroquinoline 1-oxide (4NQO)-induced rat tongue carcinogenesis model. Thirty-eight male rats were randomly divided into two groups, including the 4NQO-induced model group of 30 rats and the healthy control group of five rats. Animals were sacrificed at weeks 9, 13, 20, 24, and 32, post-4NQO treatment. Tissue samples were collected for histopathological examinations and blood samples were collected for metabolomic analysis. Partial least squares discriminate analysis (PLS-DA) models generated from GC-MS metabolic profile data showed robust discrimination from rats with oral premalignant and malignant lesions induced by 4NQO, and normal controls.

Results

The results found 16 metabolites associated with 4NQO-induced rat tongue carcinogenesis. Dysregulated arachidonic acid, fatty acid, and glycine metabolism, as well as disturbed tricarboxylic acid (TCA) cycle and mitochondrial respiratory chains were observed in the animal model. The PLS-DA models of metabolomic results demonstrated good separations between the 4NQO-induced model group and the normal control group.

Conclusion

We found several metabolites modulated by 4NQO and provide a good reference for further study of early diagnosis in oral cancer.

High Plasma Docosahexaenoic Acid Associated to Better Prognoses of Patients with Acute Decompensated Heart Failure with Preserved Ejection Fraction

The clinical relevance of polyunsaturated fatty acids (PUFAs) in heart failure remains unclear. The aim of this study was to investigate the association between PUFA levels and the prognosis of patients with heart failure with preserved ejection fraction (HFpEF). This retrospective study included 140 hospitalized patients with acute decompensated HFpEF (median age 84.0 years, 42.9% men). The patients' nutritional status was assessed, using the geriatric nutritional risk index (GNRI), and their plasma levels of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA), and dihomo-gamma-linolenic acid (DGLA) were measured before discharge. The primary outcome was all-cause mortality. During a median follow-up of 23.3 months, the primary outcome occurred in 37 patients (26.4%). A Kaplan-Meier analysis showed that lower DHA and DGLA levels, but not EPA or AA levels, were significantly associated with an increase in all-cause death (log-rank; p < 0.001 and p = 0.040, respectively). A multivariate Cox regression analysis also revealed that DHA levels were significantly associated with the incidence of all-cause death (HR: 0.16, 95% CI: 0.06-0.44, p = 0.001), independent of the GNRI. Our results suggest that low plasma DHA levels may be a useful predictor of all-cause mortality and potential therapeutic target in patients with acute decompensated HFpEF.

Is There a FADS2-Modulated Link between Long-Chain Polyunsaturated Fatty Acids in Plasma Phospholipids and Polyphenol Intake in Adult Subjects Who Are Overweight?

Dietary polyphenols promote cardiometabolic health and are linked with long-chain polyunsaturated fatty acids in plasma phospholipids (LC-PUFA). The FADS2 polymorphisms are associated with LC-PUFA metabolism and overweight/obesity. This 4-week study examined the link between polyphenol intake, FADS2 variants (rs174593, rs174616, rs174576) and obesity in 62 overweight adults (BMI ≥ 25), allocated to consume 100 mL daily of either: Aronia juice, a rich source of polyphenols, with 1177.11 mg polyphenols (expressed as gallic acid equivalents)/100 mL (AJ, n = 22), Aronia juice with 294.28 mg polyphenols/100 mL (MJ, n = 20), or nutritionally matched polyphenol-lacking placebo as a control (PLB, n = 20). We analyzed LC-PUFA (% of total pool) by gas chromatography and FADS2 variants by real-time PCR. Four-week changes in LC-PUFA, BMI, and body weight were included in statistical models, controlling for gender and PUFA intake. Only upon AJ and MJ, the presence of FADS2 variant alleles affected changes in linoleic, arachidonic, and eicosapentaenoic acid (EPA). Upon MJ treatment, changes in EPA were inversely linked with changes in BMI (β= -0.73, p = 0.029) and weight gain (β= -2.17, p = 0.024). Only in subjects drinking AJ, the link between changes in EPA and anthropometric indices was modified by the rs174576 variant allele. Our results indicate the interaction between FADS2, fatty acid metabolism, and polyphenol intake in overweight subjects.

Secular Decreasing Trend in Plasma Eicosapentaenoic and Docosahexaenoic Acids among Patients with Acute Coronary Syndrome from 2011 to 2019: A Single Center Descriptive Study

Despite intensive lipid-lowering interventions, patients treated with statins develop atherosclerotic cardiovascular disease (ASCVD), and these patients have an increased risk of developing recurrent cardiovascular events during follow-up. Therefore, there is a need to focus on the residual risks in patients in statin therapy to further reduce ASCVD. The aim of this study was to retrospectively investigate the 10-year trend (2011–2019) regarding changes in polyunsaturated fatty acids (PUFAs) in patients with acute coronary syndrome (ACS) in a single center. We included 686 men and 203 women with ACS admitted to Kagawa Prefectural Central Hospital. Plasma PUFAs, including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA), and dihomo-γ-linolenic acid (DGLA), were measured at admission for suspected ACS. A secular decreasing trend in the levels of EPA and DHA and the EPA/AA ratio, but not of AA and DGLA, was observed. The analyses based on age (>70 or <70 years) and sex showed that the decreasing trend in the levels of EPA and DHA did not depend on age and remained significant only in men. Further studies are needed to obtain robust evidence to justify that the administration of n-3 PUFA contributes to the secondary prevention of ACS.

Omega-3 polyunsaturated fatty acids focusing on eicosapentaenoic acid and docosahexaenoic acid in the prevention of cardiovascular diseases: a review of the state-of-the-art

INTRODUCTION

: An epidemiological study of Greenlandic Inuit suggested the importance of omega-3 polyunsaturated fatty acids (PUFAs) in preventing ischemic heart disease. After this landmark study, large-scale epidemiological studies have examined the benefits of omega-3 PUFAs in the prevention of cardiovascular diseases.

AREAS COVERED

: This article reviews studies on omega-3 PUFAs, and identifies issues relevant to cardiovascular risk.

EXPERT OPINION

: Recent studies have focused on the anti-inflammatory effects of omega-3 PUFAs and specialized pro-resolving mediators. High-purity eicosapentaenoic acid (EPA) ethyl ester and EPA/docosahexaenoic acid (DHA) preparations have been developed primarily for the treatment of hypertriglyceridemia. Various trials on the cardiovascular protective effects of omega-3 PUFAs have been reported, but the results have not been consistent. Some issues of the trials have been suggested, such as using low-dose omega-3 PUFAs and not including hypertriglyceridemia in subject selection criteria. REDUCE-IT study that used a high dose of high-purity EPA preparation showed a relative reduction in cardiovascular events, but, the STRENGTH study that used a high dose of EPA/DHA preparation did not support this benefit. This article reviews the roles of omega-3 PUFAs in cardiovascular diseases, including progress in understanding the molecular mechanisms and recent large-scale clinical trials.

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.

Association between serum lipids, polyunsaturated fatty acids, and prognosis in maintenance hemodialysis patients

INTRODUCTION

Risks of mortality and cardiovascular disease (CVD) are significantly higher in hemodialysis (HD) patients than in the general population, where dyslipidemia is an established risk factor for CVD and mortality. There is no clear conclusion, however, whether dyslipidemia is a significant risk factor for CVD and mortality in HD patients. Similarly, the association between the polyunsaturated fatty acids (PUFAs) and the mortality is not clear in HD patients.

METHODS

We retrospectively investigated mortality and CVD events in 420 HD patients. We classified patients into high- and low-lipid groups depending on their lipid levels. Survival rates were calculated using the Kaplan-Meier analysis and evaluated by the log-rank test. The risk estimates were computed using a multivariate Cox proportional hazard analysis.

FINDINGS

During their follow-up (June 2011 to June 2016), 151 patients died (37 of CVD), and 112 patients experienced new CVD events. On Kaplan-Meier analysis, the number of all-cause deaths and CVD events were significantly higher in the low HDL-cholesterol group (P < 0.01, log-rank test). Similarly, the number of all-cause deaths was significantly higher in the high eicosapentaenoic acid/arachidonic acid ratio group (P < 0.01, log-rank test). Multivariate Cox proportional analysis showed that HDL-cholesterol was a significant prognostic indicator for new onset of CVD events (low: 0, high: 1, hazard ratio 0.66, 95% confidence interval 0.44-0.97; P = 0.04).

DISCUSSION

In HD patients, LDL-cholesterol and non-HDL-cholesterol levels are not associated with mortality or CVD events. The HDL-cholesterol level, however, is an independent predictor of new CVD events even in HD patients.

Dietary fish and ω-3 polyunsaturated fatty acids are associated with leukocyte ABCA1 DNA methylation levels

OBJECTIVES

A diet rich in fish and ω-3 polyunsaturated fatty acids (PUFAs) has been thought to reduce the risk for cardiovascular disease (CVD). The beneficial effects of fish oil and ω-3 PUFA on CVD can be mediated by epigenetic status of the genes associated with lipid metabolism and inflammation. The aim of this study was to investigate whether dietary fish and fatty acid (FA) intakes are associated with leukocyte ATP-binding cassette transporter A1 (ABCA1) DNA methylation levels in a Japanese population.

METHODS

This cross-sectional study included 298 adults (137 men and 161 women) without clinical history of CVD or cancer. The pyrosequencing method was used to measure leukocyte ABCA1 DNA methylation levels. Dietary fish and FA intakes were assessed based on the validated food frequency questionnaire.

RESULTS

Mean ABCA1 DNA methylation levels were significantly lower in the highest fish intake groups (≥5-6/wk) compared with the lowest intake group (≤1-2/wk; P = 0.004). In multivariable linear regression analyses, higher dietary intake of ω-3 PUFAs and ω-3 highly unsaturated fatty acids was significantly associated with decreased levels of ABCA1 DNA methylation (P = 0.001 and 0.005); whereas no significant associations were seen between intake of dietary saturated fatty acid, monounsaturated fatty acid, and ω-6 PUFAs and ABCA1 DNA methylation.

CONCLUSION

Higher dietary fish and ω-3 PUFA intake were associated with lower ABCA1 DNA levels in a Japanese population. The present results may bring potential insights on biological mechanisms underlying the protective effects of dietary fish and ω-3 PUFA intakes on CVD.

The Effects of Lipid-Lowering Therapy on Serum Eicosapentaenoic Acid to Arachidonic Acid Ratio: An HIJ-PROPER Sub-Analysis

BACKGROUND

Controversy remains regarding the influence of lipid-lowering therapy on the eicosapentaenoic acid/arachidonic acid ratio.

OBJECTIVE

This study aimed to clarify the effects of lipid-lowering therapy on the eicosapentaenoic acid/arachidonic acid ratio in patients with acute coronary syndrome (ACS).

METHODS

This was a post hoc sub-analysis of the Heart Institute of Japan-PRoper level of lipid-lowering with pitavastatin and ezetimibe in ACS study. We compared the eicosapentaenoic acid/arachidonic acid ratio changes from baseline to the 3-month follow-up after contemporary lipid-lowering therapy with pitavastatin + ezetimibe therapy and pitavastatin mono-therapy.

RESULTS

Among patients with ACS and dyslipidemia, the eicosapentaenoic acid/arachidonic acid increased significantly in the pitavastatin mono-therapy group (0.40 ± 0.26 to 0.46 ± 0.34, P < .0001) but did not increase in the pitavastatin + ezetimibe group (0.37 ± 0.22 to 0.38 ± 0.27, P = .18). When the analysis was limited to patients who received 2 mg/day of pitavastatin during the follow-up period, these trends in changes of the eicosapentaenoic acid/arachidonic acid ratio remained unchanged. Multivariate analysis showed that ezetimibe use (P = .005; β = 0.09), ST-elevation myocardial infarction (P = .04; β = -0.01), and baseline low-density lipoprotein cholesterol (LDL-C) level (P = .0003; β = 0.12) were independent predictors of the percentage change in the eicosapentaenoic acid/arachidonic acid ratio. These trends were similar even when the analysis was limited to patients who did not take statins at enrollment.

CONCLUSION

Standard lipid-lowering therapy with pitavastatin mono-therapy improved the eicosapentaenoic acid/arachidonic acid ratio for patients with ACS. Intensive lipid-lowering therapy with pitavastatin + ezetimibe did not improve the eicosapentaenoic acid/arachidonic acid ratio, although LDL-C decreased significantly. Inhibition of the improvement in the eicosapentaenoic acid/arachidonic acid ratio by adding ezetimibe may affect cardiovascular disease prognosis.

Association between the ratio of serum n-3 to n-6 polyunsaturated fatty acids and acute coronary syndrome in non-obese patients with coronary risk factor: a multicenter cross-sectional study

Background

Previous studies have reported that being overweight, obese, or underweight is a risk factor for ischemic cardiovascular disease (CVD); however, CVD also occurs in subjects with ideal body mass index (BMI). Recently, the balance of n-3/n-6 polyunsaturated fatty acids (PUFAs) has received attention as a risk marker for CVD but, so far, no study has been conducted that investigates the association between BMI and the balance of n-3/n-6 PUFAs for CVD risk.

Methods

We evaluated the association between n-3/n-6 PUFA ratio and acute coronary syndrome (ACS) in three BMI-based groups (< 25: low BMI, 25–27.5: moderate BMI, and ≥ 27.5: high BMI) that included 1666 patients who visited the cardiovascular medicine departments of five hospitals located in urban areas in Japan.

Results

The prevalence of ACS events was 9.2, 7.3, and 10.3% in the low, moderate, and high BMI groups, respectively. We analyzed the relationship between ACS events and several factors, including docosahexaenoic acid/arachidonic acid (DHA/AA) ratio by multivariate logistic analyses. In the low BMI group, a history of smoking (odds ratio [OR]: 2.47, 95% confidence interval [CI]: 1.40–4.35) and low DHA/AA ratio (OR: 0.30, 95% CI: 0.12–0.74) strongly predicted ACS. These associations were also present in the moderate BMI group but the magnitude of the association was much weaker (ORs are 1.47 [95% CI: 0.54–4.01] for smoking and 0.63 [95% CI: 0.13–3.10] for DHA/AA). In the high BMI group, the association of DHA/AA (OR: 1.98, 95% CI: 0.48–8.24) was reversed and only high HbA1c (OR: 1.46, 95% CI: 1.03–2.08) strongly predicted ACS. The interaction test for OR estimates (two degrees of freedom) showed moderate evidence for reverse DHA/AA ratio–ACS associations among the BMI groups (P = 0.091).

Conclusions

DHA/AA ratio may be a useful marker for risk stratification of ACS, especially in non-obese patients.

Genome-Wide Polygenic Score and the Risk of Ischemic Stroke in a Prospective Cohort

Background and Purpose—

Environmental and genetic factors contribute to the development of ischemic stroke (IS). We recently developed a genome-wide polygenic risk score (PRS) for IS using case-control datasets from 4 large-scale observational studies conducted in Japan. Our objective in the present study was to confirm the association between the PRS and the risk of IS with data from an independent prospective cohort recruited from the general Japanese population.

Methods—

A total of 3038 subjects aged ≥40 years were followed up for 10 years (2002–2012). The genome-wide PRS was calculated using genotype data from >350 000 single-nucleotide polymorphisms. The PRS levels were divided into quintiles. High and low genetic risk groups were defined as top 60% and bottom 40% of PRS, respectively. The hazard ratio (HR) for the development of IS was estimated using a Cox proportional hazards model.

Results—

During the follow-up period, 91 cases developed first-ever IS. The age- and sex-adjusted HR for IS increased with higher PRS levels ( P for trend, 0.03). Subjects with the highest quintile level of PRS had a 2.44-fold (95% CI, 1.16–5.12) greater risk for IS than those with the lowest quintile level after adjusting for age and sex. A similar association was observed after adjusting for environmental risk factors ( P for trend, 0.03). As compared with low genetic risk group, the age- and sex-adjusted HR in high genetic risk group was 1.63 (95% CI, 1.04–2.55), which was comparable to the HR of hypertension (HR, 1.41), diabetes mellitus (HR, 1.72), and smoking (HR, 1.54). The age- and sex-adjusted HR increased with the number of environmental risk factors in both high and low genetic risk groups without significant interaction.

Conclusions—

A high genome-wide PRS was a significant risk factor for IS independent of environmental risk factors in a general Japanese population. This finding suggests that PRS may be useful to identify individuals at a high risk of IS.

Ratios of serum eicosapentaenoic acid to arachidonic acid and docosahexaenoic acid to arachidonic acid were inversely associated with serum resistin levels: The Hisayama Study

AIMS/INTRODUCTION

Resistin is an adipocyte-derived polypeptide that leads to the progression of insulin resistance and subsequent atherosclerosis. Some studies have reported an association between self-reported intake of n-3 polyunsaturated fatty acids (PUFAs) and serum resistin levels. However, no studies have investigated the association between the ratio of serum levels of n-3 to serum n-6 PUFAs and the serum resistin concentration in the general population.

MATERIALS AND METHODS

We carried out a cross-sectional study of 3,200 community-dwelling Japanese individuals aged ≥40 years in 2002-2003. The ratios of serum eicosapentaenoic acid or docosahexaenoic acid to arachidonic acid (AA) were categorized into quartiles. The associations of serum eicosapentaenoic acid/AA and docosahexaenoic acid/AA with the serum resistin concentration were assessed using linear regression models with adjustment for potential confounding factors.

RESULTS

The geometric mean of serum resistin was 10.3 ng/mL. The age- and sex-adjusted geometric mean of serum resistin decreased significantly with increased levels of serum eicosapentaenoic acid/AA (quartile 1: 11.3 ng/mL; quartile 2: 10.6 ng/mL; quartile 3: 10.3 ng/mL; quartile 4: 9.3 ng/mL; P for trend <0.001). A similar association was observed for serum docosahexaenoic acid/AA (quartile 1: 11.1 ng/mL; quartile 2: 10.6 ng/mL; quartile 3: 10.1 ng/mL; quartile 4: 9.7 ng/mL; P for trend <0.001). An adjustment for potential confounding factors did not change these associations.

CONCLUSIONS

Higher ratios of serum n-3 to n-6 PUFAs were associated with lower serum resistin levels. Consumption of a large amount of n-3 PUFAs might have desirable effects on resistin-mediated diseases.

Prevention of Cardiovascular Events with Omega-3 Polyunsaturated Fatty Acids and the Mechanism Involved

An epidemiological study of Greenlandic Inuit suggested that fish oil, or omega-3 polyunsaturated fatty acids (PUFA), was important in preventing atherosclerotic disease. After this landmark study, many large-scale epidemiological studies and meta-analyses have examined the health benefits of omega-3 PUFA as part of a fatty acid-rich diet to demonstrate its beneficial roles in the prevention of cardiovascular diseases. Recent research has also focused attention on the anti-inflammatory effects of omega-3 PUFA and on specialized pro-resolving mediators. Findings of these studies have led to the development of omega-3 PUFA preparations for the treatment of dyslipidemia, including a highly purified eicosapentaenoic acid (EPA)-ethyl ester product (Epadel^®) in Japan and an EPA/docosahexaenoic acid (DHA) preparation (Lotriga^®) in the United States and Europe. Although various large-scale clinical trials on the cardiovascular preventive effect of omega-3 PUFA were conducted and reported, the results were not always consistent. The issues of not targeting subjects with hypertriglyceridemia and using low dose of omega-3 PUFA have been suggested to contribute to the failure of demonstrating the preventive effect of omega-3 PUFA in these clinical trials. Taking into account the above issues, the REDUCE-IT trial evaluated a highly purified EPA preparation at a high dose of 4 g/day in patients with hypertriglyceridemia and high cardiovascular risk, and demonstrated an extraordinary outcome of 25% relative reduction in cardiovascular events. This article reviews studies on omega-3 fatty acids during the last 50 years, including the progress in elucidating molecular mechanisms and recent large-scale clinical studies.

Fatty Acid Profile and Cardiometabolic Markers in Relation with Diet Type and Omega-3 Supplementation in Spanish Vegetarians

Plant-based diets are becoming increasingly popular, and scientific information concerning the nutritional status in this population is needed. This study determined the fatty acid profile of Spanish lacto-ovo vegetarians (LO-vegetarians) and vegans. Participants were 104 healthy adults, LO-vegetarians (n = 49) and vegans (n = 55). Lifestyle habits and consumption of food and omega-3 supplements were estimated by questionnaires. BMI, blood pressure, and abdominal and body fat were determined. Serum was collected to analyze fatty acids, glucose, lipids, homocysteine, insulin, and leptin. Volunteers were classified according to serum omega-6 to omega-3 (n-6/n-3) ratio into three groups: n-6/n-3 < 10, n-6/n-3 ≥ 10 to 20, and n-6/n-3 > 20. Results showed low cardiovascular risk and high insulin sensitivity with negligible differences between diet types. Linoleic acid (C18:2n-6) was the major serum fatty acid, followed by oleic (C18:1n-9) and palmitic (C16:0) acids. In contrast, serum eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3) were (median, interquartile range) 0.27, 0.18% and 1.59, and 0.93%, respectively. Users of n-3 supplements (<10% of total vegetarians) had significantly higher EPA than non-users, while frequent consumption of flax-seeds was associated with increased α-linolenic acid (C18:3n-3). However, neither n-3 supplementation nor food consumption affected DHA levels in this vegetarian population.

Fatty acid desaturase 2 is up-regulated by the treatment with statin through geranylgeranyl pyrophosphate-dependent Rho kinase pathway in HepG2 cells

Statins have been reported to increase the plasma concentration of arachidonic acid (AA), an omega-6 long chain polyunsaturated fatty acid (LCPUFA) in several clinical studies indicating that statins affect the endogenous synthesis of LCUFAs. In the present study, we investigated the roles of the intrinsic mevalonate cascade and Rho-dependent pathway in LCPUFA synthesis, especially focusing on fatty acid desaturases (Fads) 2, using the human hepatocellular carcinoma cell line HepG2. Cell number and the activity of caspase-3 and 7 (caspase-3/7) was measured using a commercial kit. Gene expression was analyzed by quantitative real-time PCR. Protein expression was detected by Western blot analysis. Atorvastatin decreased cell viability and increased caspase-3/7 activity in a dose-dependent manner. At lower concentrations, atorvastatin stimulated both mRNA and protein expression of Fads2, and increased mRNA expression of FADS1 and ELVOL5. Both mevalonate and geranylgeranyl-pyrophosphate (GGPP), but not cholesterol, fully reversed atorvastatin-induced upregulation of Fads2, and mevalonate-effected reversal was inhibited by treatment with the Rho-associated protein kinase inhibitor Y-27632. These data clearly demonstrated that in human HepG2 cells, statins affect the endogenous synthesis of LCPUFAs by regulation of not only Fads2, but also Fads1 and Elovl5, through the GGPP-dependent Rho kinase pathway.

Cardiovascular, electrophysiologic, and hematologic effects of omega-3 fatty acids beyond reducing hypertriglyceridemia: as it pertains to the recently published REDUCE-IT trial

Heart disease continues to affect health outcomes globally, accounting for a quarter of all deaths in the United States. Despite the improvement in the development and implementation of guideline-directed medical therapy, the risk of adverse cardiac events remains substantially high. Historically, it has been debated whether omega-3 polyunsaturated fatty acids provide clinical benefit in cardiac disease. The recently published REDUCE-IT trial demonstrated a statistically significant absolute risk reduction of 4.8% in its primary endpoint (cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina) with the use of icosapent ethyl, which is a highly purified eicosapentaenoic acid (EPA) ethyl ester. However, the mechanism of action of omega-3 fatty acids is not commonly discussed. Moreover, the use of EPA was not without risk, as the incidence of atrial fibrillation was increased along with a trend towards increased bleeding risk. Thus, our aim is to help explain the function of purified EPA ethyl ester, especially at the molecular level, which will ultimately lead to a better understanding of their clinically observable effects.

Relationship Between Distance Run Per Week, Omega-3 Index, and Arachidonic Acid (AA)/Eicosapentaenoic Acid (EPA) Ratio: An Observational Retrospective Study in Non-elite Runners

Background: Tissue availability of polyunsaturated fatty acids (PUFA) depends on several factors, including dietary intake, physical exercise, genetic variation, and metabolic turnover. However, there is limited evidence whether running training activity per se may influence indices associated with PUFA metabolism such as Omega-3 (ω-3) index and arachidonic acid (AA; 20:4ω-6)/eicosapentaenoic acid (EPA; 20:5ω-3) ratio.

Objective: To examine the association between kilometers (Km) run per week and changes in ω-3 index and AA/EPA ratio.

Methods: We conducted a retrospective, observational, cohort study of 257 non-elite runners (mean age: 40.85 ± 12.17 years) who consumed no fatty acid supplements and provided a blood sample for analysis. The whole blood samples were collected by finger sticks, stored on absorbent filter paper, and then PUFA were quantified by gas chromatography (GC) and ω-3 index and AA/EPA ratio measured.

Results: In a multivariate linear regression model, a gradual decrease of the ω-3 index was observed with higher weekly running distance (β = −0.033; 95% CI −0.039 to −0.026; R² = 0.447; p < 0.0001). We also found a progressive increase of the AA/EPA ratio in subjects who ran greater weekly distances (β = 0.092; 95% CI 0.038 to 0.146; R² = 0.320; p = 0.001). No other significant associations were observed with other variables, including years of running training and weekly training frequency (hours/week). Finally, as expected, a significant inverse correlation between ω-3 index and AA/EPA ratio (β = −2.614; 95% CI −3.407 to −1.821; R² = 0.336; p < 0.0001) was detected.

Conclusions: These findings suggest that distance running training and its weekly volume may negatively contribute to changes of the ω-3 index and AA/EPA ratio. Further studies with greater sample size will be required to replicate and extend these data.

Effects of fatty and lean fish intake on stroke risk: a meta-analysis of prospective cohort studies

BACKGROUND

Fish intake has been postulated to reduce the risk of stroke. However, whether the beneficial effect of fish are mainly linked to fat content, as a source of omega-3 polyunsaturated fatty acids, remains unclear. We conducted a meta-analysis to compare the effect of fatty and lean fish intake on stroke risk.

METHODS

We performed a literature search on four database (PubMed, Embase, Scopus, and Cochrane Library) through February 1, 2018 to identify prospective studies of fatty and lean fish in relation to stroke risk. A random-effects model was used to calculate the summary estimates.

RESULTS

We identified five prospective studies, including 7 comparisons for fatty fish intake and 5 comparisons for lean fish intake. Compared with the highest category of intake with lowest category, the summary relative risk was 0.88 [95% confidence interval (CI), 0.74-1.04] for fatty fish intake and 0.81 (95% CI, 0.67-0.99) for lean fish intake. No heterogeneity across studies and publication bias were observed.

CONCLUSION

Our findings demonstrated that fatty and lean fish intake has beneficial effects on stroke risk, especially lean fish intake. Additional prospective studies are necessary to confirm these observations.

Variations in the eicosapentaenoic acid-arachidonic acid ratio associated with age in acute myocardial infarction patients undergoing primary percutaneous coronary intervention

Acute myocardial infarction (AMI) is a life-threatening disease, and its incidence has been increasing even in the young population. Although a low eicosapentaenoic acid (EPA)-arachidonic acid (AA) ratio is associated with an increased risk of coronary artery disease, the effect of age on EPA/AA ratios in AMI patients remains unclear. This study aimed to clarify the independent polyunsaturated fatty acid (PUFA)-related determinants of age in younger and older AMI patients. A total of 153 consecutive patients who underwent primary percutaneous coronary interventions (PCIs) for de novo AMIs were enrolled in this study. Patients' background data, including PUFA and lipid profiles during PCI, were evaluated retrospectively. The EPA/AA ratio correlated positively with age (r = 0.21; P = 0.011) and increased markedly from age 60 years. Patients aged < 60 years (n = 35) had a lower mean EPA/AA ratio (0.25 ± 0.16) than patients aged ≥ 60 years (n = 118) (0.38 ± 0.25) (P < 0.001). The AA level was more dependent on age than on EPA level (r = - 0.34, P < 0.001 vs. r = 0.12, P = 0.16). The multivariate analysis revealed that a 0.1 EPA/AA ratio increase (odds ratio 1.50; 95% confidence interval 1.09-2.06), body mass index, triglyceride level, and aspirin administration were independently associated with the age stratification of AMI patients. The EPA/AA ratio was higher in younger AMI patients who have undergone primary PCIs than in older patients. Younger population at risk for AMI should be managed with multiple interventions including PUFA profiling.