Higher docosahexaenoic acid levels lower the protective impact of eicosapentaenoic acid on long-term major cardiovascular events

Omega and heart rate variability in overweight and obese schoolchildren

BACKGROUND

Overweight and obese children are risky for developing chronic cardiovascular disorders. Heart rate variability is a valuable indicator of the cardiovascular health.

AIM

To outline the impact of supplementation of omega-3 on the variability of the heart rate.

METHODS

A randomized interventional control study has been done on 60 overweight and obese children; 30 children were assigned to the interventional group who received omega-3 with the standard recommendations and 30 children were assigned to the control group who received the standard recommendations only. Resting 10 min Holter ECG was done at the start and after 3 months of omega-3 supplementation in both groups to observe and compare the difference in the heart rate variability. In addition, lipid profiles were investigated and compared.

RESULTS

Difference in measures of the heart rate variability; RMSSD, SDNN, and pNN50 were increased significantly in cases compared to the controls (P value = 0.017, 0.009, and 0.043 respectively). Differences in measures of the lipid profiles differed only in triglycerides which decreased significantly in cases and HDL which increased significantly in the cases (P value = 0.006, 0.005 respectively).

CONCLUSION

Our results suggested that omega-3 supplementation might improve cardiovascular health in overweight and obese children.

IMPACT

This study discloses the importance of supplementation of omega-3 fatty acids as a cardioprotective dietary supplement. Omega-3 fatty acids can improve heart rate variability in overweight and obese children. Omega-3 fatty acids can also improve the lipid profiles in overweight and obese children.

Palmitoleic and oleic fatty acids as biomarkers for coronary heart disease: A predictive model

BACKGROUND

saturated and unsaturated fatty acid showed a significant link with coronary artery health and disease.

OBJECTIVE

This study aimed to compare plasma levels of unsaturated fatty acids (UFAs) between individuals with coronary heart disease (CHD) and those without. It also investigated the association between specific UFA ratios and the presence or severity of acute coronary syndrome (ACS). Additionally, the study explored the potential of UFAs as biomarkers for assessing CHD risk or disease severity.

METHOD

Patients suspected of coronary heart disease (CHD) at Northern Jiangsu People's Hospital were categorized by coronary angiography into non-CHD (53 cases) and CHD (182 cases). The CHD group was divided into non-acute coronary syndrome (non-ACS) (40 cases) and ACS (142 cases) subgroups. The ACS group was further classified into unstable angina (61 cases), non-ST-elevation myocardial infarction (NSTEMI) (40 cases), and ST-elevation myocardial infarction (STEMI) (41 cases). Lipid profiles, myocardial injury markers, and fourteen unsaturated fatty acids were analyzed using liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS).

RESULTS

The CHD group had significantly higher triglycerides (TG), palmitoleic acid (PA), oleic acid (OA), docosahexaenoic acid (DHA), ω-6 fatty acids, and a higher ω-6/ω-3 ratio, but lower ω-3 fatty acids compared to non-CHD. In ACS, PA, LA, OA, and the ω-6/ω-3 ratio were elevated, while EPA and HDL were reduced. Logistic regression identified TG, ω-6/ω-3 ratio, PA, OA, and ω-6 fatty acids as risk factors, with ω-3 fatty acids being protective. PA was protective, while OA posed risk. A combined PA and OA model had a diagnostic efficacy (AUC 0.746).

CONCLUSION

Altered fatty acid metabolism in CHD patients, particularly PA and OA, offers potential as biomarkers. The ω-6/ω-3 ratio is crucial for cardiovascular health.

The Optimal Dosage and Duration of ω-3 PUFA Supplementation in Heart Failure Management: Evidence from a Network Meta-Analysis

Heart failure is a progressive condition associated with a high mortality rate. Despite advancements in treatment, many patients continue to experience less-than-ideal outcomes. ω-3 (n-3) polyunsaturated fatty acids (PUFAs) have been studied as a potential supplementary therapy for heart failure, but the optimal dosage and duration of supplementation remain unclear. This network meta-analysis (NMA) aimed to assess the efficacy of various n-3 PUFA supplementation regimens in patients with heart failure, focusing on dose-dependent and time-dependent effects. We conducted a systematic search for randomized controlled trials (RCTs) on n-3 PUFA supplementation in heart failure till 13 September, 2024. The primary outcome was the change in heart function, specifically left ventricular ejection fraction. Secondary outcomes included changes in peak oxygen consumption (VO2), blood B-type natriuretic peptide concentrations, and quality of life. The safety analysis focused on dropout rates (i.e., patients leaving the study for any reason before completion) and all-cause mortality. A frequentist-based NMA was performed. This NMA, which included 14 RCTs with 9075 participants (mean age, 66.0 y; 23.3% female), found that high-dose n-3 PUFA supplementation (2000-4000 mg/d) over a duration of ≥1 y significantly improved left ventricular ejection fraction and peak VO2 compared with those of control groups. Lower doses and shorter treatment periods did not produce the same benefits. No significant differences were found in dropout rates or all-cause mortality between the n-3 PUFAs and control groups. Long-term, high-dose n-3 PUFA supplementation, particularly with a predominance of docosahexaenoic acid or eicosapentaenoic acid, enhances cardiac function in patients with heart failure without increasing risk of adverse events. Further well-designed RCTs with long treatment durations (i.e., >1 y) and stringent heart failure inclusion criteria are necessary to confirm these findings and reduce potential biases. This trial was registered at PROSPERO as CRD42024590476.

Associations of the intake of individual and multiple fatty acids with depressive symptoms among adults in NHANES 2007-2018

BACKGROUND

Previous studies have mainly focused on the effects of individual fatty acids on depressive symptoms, while the combined effect of fatty acids on the risk of depressive symptoms has not yet been extensively reported. This study evaluate the associations between individual and multiple fatty acids with depressive symptoms in U.S. adults.

METHODS

Data sets were obtained from the National Health and Nutrition Examination Survey (NHANES) 2007-2018 cycles. Both males and females aged above 18 years with complete information about dietary fatty acids intake, depression symptoms, and covariates were included. Weighted linear regression models were conducted to evaluate the relationships between individual fatty acid intake and depressive symptoms, and restricted cubic spline (RCS) models were utilized to explore the corresponding dose-response relationships. Additionally, we implemented the weighted quantile sum (WQS) regression and quantile g-computation (QGC) models to estimate the mixed effects of 19 fatty acids and identify the predominant types.

RESULTS

After multivariable adjustments, an increase of one unit in Linoleic acid (LA), Alpha-Linolenic Acid (ALA), Arachidonic acid (AA), Docosapentaenoic acid(DPA), Docosahexaenoic acid(DHA), was associated with a decrease in depressive scores by -0.021 (95 % CI: -0.039,-0.003, p = 0.021),-0.028 (95 % CI: -0.045,-0.011, p = 0.002),-0.026 (95 % CI: -0.044,-0.008, p = 0.005), -0.026 (95 % CI: -0.042,-0.009, p = 0.003), and - 0.022 (95 % CI: -0.041,-0.003, p = 0.022), respectively. However, a per unit increase in Hexanoic acid and Octanoic acid was associated with an increase in depressive scores of 0.020 (95 % CI: 0.002,0.038, p = 0.029) and 0.026 (95 % CI: 0.004,0.048, p = 0.020), respectively. Meanwhile, significant dose-response relationships were supported by the RCS models. As for the mixed effects, both WQS and QGC models demonstrated that the mixture of polyunsaturated fatty acids (PUFAs) was inversely related to depressive symptoms, and ALA and DPA were the most critical contributors. DHA was negatively correlated with depressive symptoms in WQS analysis, but positively correlated with depressive symptoms in QGC analysis.

LIMITATIONS

The cross-sectional design limits our ability to establish causality, and 24-hour dietary recall can lead to potential inaccuracies reflecting participants' true eating habits.

CONCLUSION

Our study suggests that the single effects of each PUFA were inversely associated with depressive symptoms, except for octadecatetraenoic acid. Moreover, higher combined intake of dietary PUFAs is inversely associated with depressive symptoms in U.S. adults. Among the mixed effects of PUFAs, ALA and DPA may play predominant roles. However, DHA mixed with other fatty acids may have different effects on depressive symptoms, and further study is needed.

Role of Omega-3 fatty acids eicosapentaenoic (EPA) and docosahexaenoic (DHA) as modulatory and anti-inflammatory agents in noncommunicable diet-related diseases - Reports from the last 10 years

BACKGROUND & AIMS

Fatty acids are a fundamental component of the human diet, particularly polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The importance of omega-3 fatty acids has been studied in the context of many diseases due to their pleiotropic effects, focusing on the anti-inflammatory effects of EPA and DHA. Currently, the results of these acids in noncommunicable diseases are being increasingly assessed in a broader context than just inflammation. However, the mechanisms underlying the modulatory and anti-inflammatory effects of omega-3 fatty acids remain the subject of intensive research. Therefore, we reviewed the literature covering articles from the last decade to assess not only the anti-inflammatory but, above all, the modulatory effect of EPA and DHA acids on noncommunicable diet-related diseases.

METHODS

The PubMed, Web of Science and Scopus databases were searched for studies regarding the effects of omega-3 fatty acids on diet-related disorders from the last 10 years.

RESULTS

The available research shows that EPA and DHA supplementation has a beneficial impact on regulating triglycerides, total cholesterol, insulin resistance, blood pressure, liver enzymes, inflammatory markers and oxidative stress. Additionally, there is evidence of their potential benefits in terms of mitochondrial function, regulation of plasma lipoproteins, and reduction of the risk of sudden cardiovascular events associated with atherosclerotic plaque rupture.

CONCLUSIONS

Omega-3 polyunsaturated fatty acids (EPA, DHA) have many beneficial effects among patients with diet-related disorders. More well-designed randomised controlled trials are needed to fully determine the usefulness of EPA and DHA in treating and preventing noncommunicable diet-related diseases.

EPA, DHA, and resolvin effects on cancer risk: The underexplored mechanisms

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplements have exhibited inconsistent effects on cancer risk, and their potential efficacy as cancer preventive agents has been increasingly questioned, especially in recent large randomized clinical trials. The role of host factors that govern EPA and DHA metabolism in relation to their impact on carcinogenesis remains understudied. Resolvins, the products of EPA and DHA oxidative metabolism, demonstrate intriguing antitumorigenic effects through mechanisms such as promoting macrophage phagocytosis of cell debris and inhibiting the production of proinflammatory chemokines and cytokines by tumor-associated macrophages (TAMs), which are crucial for cancer progression. However, clinical studies have not yet shown a significant increase in target tissue levels of resolvins with EPA and DHA supplementation. 15-Lipoxygenase-1 (ALOX15), a key enzyme in EPA and DHA oxidative metabolism, is often lost in various major human cancers, including precancerous and advanced colorectal cancers. Further research is needed to elucidate whether the loss of ALOX15 expression in colorectal precancerous and cancerous cells affects EPA and DHA oxidative metabolism, the formation of resolvins, and subsequently carcinogenesis. The findings from these studies could aid in the development of novel and effective chemoprevention interventions to reduce cancer risk.

Beyond LDL-C: unravelling the residual atherosclerotic cardiovascular disease risk landscape-focus on hypertriglyceridaemia

Aims

Historically, atherosclerotic cardiovascular disease (ASCVD) risk profile mitigation has had a predominant focus on low density lipoprotein cholesterol (LDL-C). In this narrative review we explore the residual ASCVD risk profile beyond LDL-C with a focus on hypertriglyceridaemia, recent clinical trials of therapeutics targeting hypertriglyceridaemia and novel modalities addressing other residual ASCVD risk factors.

Findings

Hypertriglyceridaemia remains a significant ASCVD risk despite low LDL-C in statin or proprotein convertase subtilisin/kexin type 9 inhibitor-treated patients. Large population-based observational studies have consistently demonstrated an association between hypertriglyceridaemia with ASCVD. This relationship is complicated by the co-existence of low high-density lipoprotein cholesterol. Despite significantly improving atherogenic dyslipidaemia, the most recent clinical trial outcome has cast doubt on the utility of pharmacologically lowering triglyceride concentrations using fibrates. On the other hand, purified eicosapentaenoic acid (EPA), but not in combination with docosahexaenoic acid (DHA), has produced favourable ASCVD outcomes. The outcome of these trials suggests alternate pathways involved in ASCVD risk modulation. Several other pharmacotherapies have been proposed to address other ASCVD risk factors targeting inflammation, thrombotic and metabolic factors.

Implications

Hypertriglyceridaemia poses a significant residual ASCVD risk in patients already on LDL-C lowering therapy. Results from pharmacologically lowering triglyceride are conflicting. The role of fibrates and combination of EPA and DHA is under question but there is now convincing evidence of ASCVD risk reduction with pure EPA in a subgroup of patients with hypertriglyceridaemia. Clinical guidelines should be updated in line with recent clinical trials evidence. Novel agents targeting non-conventional ASCVD risks need further evaluation.

Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) Ameliorate Heart Failure through Reductions in Oxidative Stress: A Systematic Review and Meta-Analysis

The objectives of this study were to explore the role that eicosapentaenoic acid (EPA) and/or docosahexaenoic acid (DHA) plays in heart failure (HF), highlighting the potential connection to oxidative stress pathways. Following PRISMA guidelines, we conducted electronic searches of the literature in MEDLINE and EMBASE focusing on serum EPA and/or DHA and EPA and/or DHA supplementation in adult patients with heart failure or who had heart failure as an outcome of this study. We screened 254 studies, encompassing RCTs, observational studies, and cohort studies that examined HF outcomes in relation to either serum concentrations or dietary supplementation of EPA and/or DHA. The exclusion criteria were pediatric patients, non-HF studies, abstracts, editorials, case reports, and reviews. Eleven studies met our criteria. In meta-analyses, high serum concentrations of DHA were associated with a lower rate of heart failure with a hazard ratio of 0.74 (CI = 0.59-0.94). High serum concentrations of EPA also were associated with an overall reduction in major adverse cardiovascular events with a hazard ratio of 0.60 (CI = 0.46-0.77). EPA and DHA, or n3-PUFA administration, were associated with an increased LVEF with a mean difference of 1.55 (CI = 0.07-3.03)%. A potential explanation for these findings is the ability of EPA and DHA to inhibit pathways by which oxidative stress damages the heart or impairs cardiac systolic or diastolic function producing heart failure. Specifically, EPA may lower oxidative stress within the heart by reducing the concentration of reactive oxygen species (ROS) within cardiac tissue by (i) upregulating nuclear factor erythroid 2-related factor 2 (Nrf2), which increases the expression of antioxidant enzyme activity, including heme oxygenase-1, thioredoxin reductase 1, ferritin light chain, ferritin heavy chain, and manganese superoxide dismutase (SOD), (ii) increasing the expression of copper-zinc superoxide dismutase (MnSOD) and glutathione peroxidase, (iii) targeting Free Fatty Acid Receptor 4 (Ffar4), (iv) upregulating expression of heme-oxygenase-1, (v) lowering arachidonic acid levels, and (vi) inhibiting the RhoA/ROCK signaling pathway. DHA may lower oxidative stress within the heart by (i) reducing levels of mitochondrial-fission-related protein DRP-1(ser-63), (ii) promoting the incorporation of cardiolipin within the mitochondrial membrane, (iii) reducing myocardial fibrosis, which leads to diastolic heart failure, (iv) reducing the expression of genes such as Appa, Myh7, and Agtr1α, and (v) reducing inflammatory cytokines such as IL-6, TNF-α. In conclusion, EPA and/or DHA have the potential to improve heart failure, perhaps mediated by their ability to modulate oxidative stress.

Dietary docosahexaenoic acid (DHA) downregulates liver DHA synthesis by inhibiting eicosapentaenoic acid elongation

DHA is abundant in the brain where it regulates cell survival, neurogenesis, and neuroinflammation. DHA can be obtained from the diet or synthesized from alpha-linolenic acid (ALA; 18:3n-3) via a series of desaturation and elongation reactions occurring in the liver. Tracer studies suggest that dietary DHA can downregulate its own synthesis, but the mechanism remains undetermined and is the primary objective of this manuscript. First, we show by tracing 13C content (δ13C) of DHA via compound-specific isotope analysis, that following low dietary DHA, the brain receives DHA synthesized from ALA. We then show that dietary DHA increases mouse liver and serum EPA, which is dependant on ALA. Furthermore, by compound-specific isotope analysis we demonstrate that the source of increased EPA is slowed EPA metabolism, not increased DHA retroconversion as previously assumed. DHA feeding alone or with ALA lowered liver elongation of very long chain (ELOVL2, EPA elongation) enzyme activity despite no change in protein content. To further evaluate the role of ELOVL2, a liver-specific Elovl2 KO was generated showing that DHA feeding in the presence or absence of a functional liver ELOVL2 yields similar results. An enzyme competition assay for EPA elongation suggests both uncompetitive and noncompetitive inhibition by DHA depending on DHA levels. To translate our findings, we show that DHA supplementation in men and women increases EPA levels in a manner dependent on a SNP (rs953413) in the ELOVL2 gene. In conclusion, we identify a novel feedback inhibition pathway where dietary DHA downregulates its liver synthesis by inhibiting EPA elongation.