Plasma DHA Research Articles

Comparative Effectiveness of Ascorbic Acid vs. Calcium Ascorbate Ingestion on Pharmacokinetic Profiles and Immune Biomarkers in Healthy Adults: A Preliminary Study.

Previous trials have displayed augmented intracellular vitamin C concentrations in the leukocytes at 24 h after acute supplementation with 1000 mg calcium ascorbate (CA), compared to ascorbic acid (AA). The primary objective was to evaluate comparative leukocyte vitamin C accumulation kinetics over 32 h following acute 250 mg or 500 mg doses from the two sources. Secondary objectives were to evaluate neutrophil phagocytic function and lymphocyte differentiation between the two sources of vitamin C. Ninety-three healthy females (250 mg, n = 27; 500 mg, n = 24) and males (250 mg, n = 19; 500 mg, n = 23) were assigned to ingest a single dose of CA or AA providing 250 mg or 500 mg of vitamin C in two separate double-blind, randomized crossover trials. There were no significant differences in the primary or secondary outcomes between the two treatments in the 250 mg low-dose study. Conversely, there was evidence that ingestion of 500 mg of CA increased DHA in plasma, increased neutrophil functionality during the first 8 h of the PK study, promoted increased natural killer cells, and altered weight-adjusted PK profiles, suggesting greater volume distribution and clearance from the blood. These findings indicate that 500 mg of CA may promote some immune benefits compared to 500 mg of AA ingestion.

Plasma levels of EPA and DHA after ingestion of a single dose of EPA and DHA ethyl esters

AbstractOmega‐3 polyunsaturated fatty acids (n3 PUFA), specifically eicosapentaenoic acid (EPA, 20:5n3), and docosahexaenoic acid (DHA, 22:6n3), are essential for maintaining health. To better understand their biology, it is important to define their bioavailability. The aim of this cross‐over study was to investigate and compare the acute effects on plasma EPA and DHA levels after single doses of EPA oil (99% pure) and DHA (97% pure) ethyl esters. Twelve men aged 20–40 years with a body‐mass‐index of 20–27 kg/m2 and low fish consumption were recruited. Several measures (e.g., 4‐week run‐in period, standardized diet, and blood collection protocols) were taken to reduce the inter‐individual variability of plasma fatty acids levels. Using a cross‐over design, the subjects received 2.2 g of EPA in the first test period and 2.3 g of DHA in the second. The test periods were separated by 2 weeks. Blood samples were taken before dosing and after 2, 4, 6, 8, 12, 24, 48, and 72 h. The mean ± SE maximum concentrations for EPA were higher than for DHA (115 ± 11 μg/mL vs. 86 ± 12 μg/mL; p = 0.05). The mean ± SE incremented area under the plasma concentration curve over 72 h for EPA (2461 ± 279 μg/mL) was 2.4 times higher (p < 0.001) than that for DHA (1021 ± 170 μg/mL). The mean ± SE half‐life was for EPA and DHA was 45 ± 8 and 66 ± 12 h. Our results indicate that EPA administration in single doses leads to higher circulating plasma levels of EPA compared to an effect of an equivalent dose of DHA on DHA plasma levels.

Higher docosahexaenoic acid proportions in blood are inversely associated with the prevalence of prediabetes: Evidence from the UK Biobank

Prediabetes and type 2 diabetes mellitus are growing global health concerns, predisposing individuals to various vascular complications. Lifestyle modifications, including dietary interventions, offer promising avenues for prevention and management. Using a multivariable-adjusted model, we analyzed the cross-sectional associations between plasma proportions (% of total fatty acids) of omega-3 polyunsaturated fatty acids (n3 PUFA, including total n3 PUFA, docosahexaenoic acid [DHA], non-DHA n3 PUFA), and glycated hemoglobin A1c (HbA1c) as well as the prevalence of prediabetes in a sample from the UK Biobank cohort. Our hypothesis was that proportions of n3 PUFA, especially DHA, would by inversely associated with the prediabetes prevalence. The sample (n = 92,762; 54.5% females) had an average age of 56 years and was overweight (mean body mass index = 27). The mean plasma DHA proportion in the sample was 2.03% (standard deviation [SD] = 0.67%), non-DHA n3 PUFA was 2.41% (SD = 1.02%) and total n3 PUFA was 4.43% (SD = 1.56%). Prediabetic individuals were identified by blood HbA1c proportions between 5.7% and 6.4% (39-46 mmol/mol) according to American Diabetes Association criteria. Each of the three n3 PUFA biomarkers was inversely associated with HbA1c proportions. In particular, DHA showed the strongest inverse association, with an OR of 0.62 (95% confidence intervals: 0.58, 0.67; P < .001) when comparing quintiles 5 to 1 in a fully adjusted model. These findings suggest a potential protective role of n3 PUFA, particularly DHA, in mitigating the risk of having prediabetes. Further prospective investigations are needed to clarify whether long-chain n3 PUFA could function as modifiable factors for prediabetes.

#2556 Therapeutic monitoring in patients with APRT deficiency using UPLC-MS/MS-based plasma assay

Abstract Background and Aims Adenine phosphoribosyltransferase (APRT) deficiency is a rare disorder of purine metabolism, characterized by urinary excretion of the poorly soluble 2,8-dihydroxyadenine (DHA), leading to nephrolithiasis and chronic kidney disease (CKD). Treatment with xanthine oxidoreductase (XOR) inhibitor, allopurinol or febuxostat, reduces DHA excretion and slows or halts CKD progression. The aim of the study was to optimize and validate an ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS)-based assay for simultaneous quantification of DHA, adenine, allopurinol, oxypurinol and febuxostat in human plasma, for monitoring of pharmacotherapy in patients with APRT deficiency. Method The UPLC-MS/MS-based assay was optimized employing the chemometric approach design of experiments, using the software Modde Pro 13 (Sartorius, Umeå, Sweden). The assay was validated and used for absolute quantification of DHA, adenine, allopurinol, oxypurinol and febuxostat in plasma samples from both untreated and treated APRTd patients and healthy controls. Results Accuracy and precision were within ±15% for all analytes, and the analytes were stable in plasma for 12 months at −80°C. The median (range) concentration of DHA in plasma samples from six APRT deficiency patients was 204.0 (187.2–315.8) ng/mL when they were untreated and 69.2 (below the limit of quantification [BLQ]–131.6) ng/mL when treated with allopurinol (400 mg/day), and BLQ when febuxostat (80 mg/day) was the therapeutic agent. The median (range) plasma adenine concentration was 238.1 (218–502) ng/mL in the untreated patients, and 561.1 (418–2104) and 856.0 (726–1711) ng/mL in those on treatment with allopurinol and febuxostat, respectively. DHA was not detected in plasma samples from healthy controls. The median (range) plasma concentration of allopurinol, oxypurinol and febuxostat in patients receiving XOR inhibitor therapy was 1657 (BLQ-3266) ng/mL, 8102 (4778–34906) ng/mL and 109 (BLQ-1657) ng/mL, respectively. Conclusion The UPLC-MS/MS-based assay provides accurate and precise quantification of DHA, adenine, allopurinol, oxypurinol and febuxostat in human plasma. Measurement of plasma DHA is being implemented as a diagnostic test for APRT deficiency and the full assay for monitoring of XOR inhibitor treatment in patients with the disorder.

Sex differences in lipid mediators derived from omega-3 fatty acids in older individuals with low-grade chronic inflammation.

The rate of cardiovascular disease (CVD) death is higher in men than women before age 50 y, but the gap between sexes significantly narrows after menopause. Lipid mediators derived from EPA, DHA and AA play a role in inflammation and CVD. The aim of our study was to assess whether plasma concentrations of these lipid mediators differ between postmenopausal women and men. Twelve postmenopausal women and 9 men with low-grade chronic inflammation completed a randomized, double-blind, crossover study consisting of a 4-week lead-in placebo phase (3 g/d high-oleic acid sunflower oil) followed by randomization to either 3 g/d DHA or 3 g/d EPA for 10 weeks and crossover for additional 10 weeks, separated by a washout phase. Plasma phospholipid content of EPA, DHA and AA and plasma concentrations of their derived lipid mediators were measured at the end of the placebo lead-in phase (baseline) and the DHA and EPA supplementation phases. There were no sex differences in plasma phospholipid EPA, DHA and AA at baseline and after DHA and EPA supplementation. However, plasma concentrations of lipid mediators derived from EPA, DHA and AA via 15-lipoxygenase were lower in postmenopausal women than men, especially after supplementation. Sex differences in EPA- and DHA-derived lipid mediators with anti-inflammatory and pro-resolving actions may partly explain the faster rise in CVD in postmenopausal women than age-matched men.

Cross-sectional analysis of plasma n-3 fatty acid levels and self-reported hearing difficulty in the UK Biobank Cohort

BackgroundDisabling hearing loss affects ∼430 million people globally. Fish consumption and long-chain n-3 polyunsaturated fatty acid (PUFA) intake were inversely associated with risk of hearing loss, but the association of plasma n-3 PUFAs and hearing loss is unclear. ObjectiveTo examine the associations between plasma n-3 PUFA fractions (as % of total fatty acids), i.e., DHA% and Other n-3 PUFA% (defined as total n-3 PUFA minus DHA), with self-reported hearing difficulty in a population-based cohort in the UK. MethodsOur study includes 175,177 UK Biobank participants (40-69y, 54% women) with data on plasma n-3 PUFA and hearing status. Baseline plasma PUFA levels were analyzed by nuclear magnetic resonance, and self-reported hearing difficulty was obtained by questionnaire between 2007 and 2010. Logistic regression was used to estimate age-adjusted odds ratios (ORs), multivariable-adjusted odds ratios (MVORs) by adjusting for 14 demographic, behavioral, biomarker and health-related potential confounders, and 95% confidence intervals (CIs). ResultsHearing difficulty was reported by 26.7% of participants. Higher plasma n-3 PUFA levels were independently associated with lower odds of self-reported hearing difficulty. The prevalence of hearing difficulty rose across age strata (40-49y, 15.8%; 50-59y, 24.9% and 60+y, 34.4%; p<0.0001) and overall was higher in males (33.2%) than females (21.3%). Compared with those in the lowest quintile of plasma DHA% or Other n-3 PUFA%, the MVOR (95% CI) for hearing difficulty was 0.88 (0.85, 0.92) in highest quintile of plasma DHA%, and 0.91 (0.87, 0.94) in the highest quintile of Other n-3 PUFA%. The associations with DHA% did not differ by age or sex (p-for-interaction 0.83and 0.58, respectively). MVORs for DHA% and Other n-3 PUFA% were similar among the 44,486 individuals with data on noise exposure at work. ConclusionsHigher plasma n-3 PUFA levels were independently associated with lower odds of hearing difficulty.

Types of fish consumption differ across socioeconomic strata and impact differently on plasma fish-based omega-3 fatty acids: a cross-sectional study

PurposeWe investigated the associations of socioeconomic position (SEP) with total and type of fish intake in a large general population and validated whether types of fish intake were differently associated with plasma EPA and DHA in a subset of the population.MethodsFrom the Lifelines Cohort Study, 94,246 participants aged 44 ± 13 years old were included to test the association of two SEP indicators, i.e., education level and household income level, with dietary intakes of total, oily, lean, fried, and other types of fish. In a subset of 575 participants (mean age: 50 ± 13 years), EPA and DHA levels were measured in plasma phospholipids and triglycerides. Dietary fish intake was assessed using Food Frequency Questionnaire. Linear regressions were applied and adjusted for relevant covariates.ResultsCompared to the high education level, lower education levels were negatively associated with total, oily, lean, and other fish intake (p < 0.001 for all), and positively associated with fried fish intake (β (SE): 0.04 (0.04), p < 0.001 for middle education; 0.07 (0.04), p < 0.001 for low education), independently of relevant covariates. Similar results were observed for income levels. In the subset population, total and oily fish intakes were positively associated with plasma EPA and DHA (p < 0.02 for all). Lean and other fish intakes were positively associated with only DHA (p < 0.008 for all), but not EPA, while fried fish was not associated with either EPA or DHA in plasma (p > 0.1 for all).ConclusionLower SEP was associated with a lower total intake of fish, and of oily and lean fish, but with higher intake of fried fish. Fried fish was not associated with the fish-based EPA and DHA in plasma. Hence, SEP-related differences in fish consumption are both quantitative and qualitative.

Analysis of omega-3 and omega-6 polyunsaturated fatty acid metabolism by compound-specific isotope analysis in humans

Natural variations in the 13C:12C ratio (carbon-13 isotopic abundance [δ13C]) of the food supply have been used to determine the dietary origin and metabolism of fatty acids, especially in the n-3 PUFA biosynthesis pathway. However, n-6 PUFA metabolism following linoleic acid (LNA) intake remains under investigation. Here, we sought to use natural variations in the δ13C signature of dietary oils and fatty fish to analyze n-3 and n-6 PUFA metabolism following dietary changes in LNA and eicosapentaenoic acid (EPA) + DHA in adult humans. Participants with migraine (aged 38.6 ± 2.3 years, 93% female, body mass index of 27.0 ± 1.1 kg/m2) were randomly assigned to one of three dietary groups for 16 weeks: 1) low omega-3, high omega-6 (H6), 2) high omega-3, high omega-6 (H3H6), or 3) high omega-3, low omega-6 (H3). Blood was collected at baseline, 4, 10, and 16 weeks. Plasma PUFA concentrations and δ13C were determined. The H6 intervention exhibited increases in plasma LNA δ13C signature over time; meanwhile, plasma LNA concentrations were unchanged. No changes in plasma arachidonic acid δ13C or concentration were observed. Participants on the H3H6 and H3 interventions demonstrated increases in plasma EPA and DHA concentration over time. Plasma δ13C-EPA increased in total lipids of the H3 group and phospholipids of the H3H6 group compared with baseline. Compound-specific isotope analysis supports a tracer-free technique that can track metabolism of dietary fatty acids in humans, provided that the isotopic signature of the dietary source is sufficiently different from plasma δ13C.

A combined DHA-rich fish oil and cocoa flavanols intervention does not improve cognition or brain structure in older adults with memory complaints: results from the CANN randomized, controlled parallel-design study

BackgroundThere is evidence that both omega-3 long-chain polyunsaturated fatty acids (PUFAs) (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) and cocoa flavanols can improve cognitive performance in both healthy individuals and in those with memory complaints. However, their combined effect is unknown. ObjectivesTo investigate the combined effect of EPA/DHA and cocoa flavanols (OM3FLAV) on cognitive performance and brain structures in older adults with memory complaints. MethodsA randomized placebo-controlled trial of DHA-rich fish oil (providing 1.1 g/d DHA and 0.4 g/d EPA) and a flavanol-rich dark chocolate (providing 500 mg/d flavan-3-ols) was conducted in 259 older adults with either subjective cognitive impairment or mild cognitive impairment. Participants underwent assessment at baseline, 3 mo, and 12 mo. The primary outcome was the number of false-positives on a picture recognition task from the Cognitive Drug Research computerized assessment battery. Secondary outcomes included other cognition and mood outcomes, plasma lipids, brain-derived neurotrophic factor (BDNF), and glucose levels. A subset of 110 participants underwent structural neuroimaging at baseline and at 12 mo. Results197 participants completed the study. The combined intervention had no significant effect on any cognitive outcomes, with the exception of reaction time variability (P = 0.007), alertness (P < 0.001), and executive function (P < 0.001), with a decline in function observed in the OM3FLAV group (118.6 [SD 25.3] at baseline versus 113.3 [SD 25.4] at 12 mo for executive function) relative to the control, and an associated decrease in cortical volume (P = 0.039). Compared with the control group, OM3FLAV increased plasma HDL, total cholesterol ratio (P < 0.001), and glucose (P = 0.008) and reduced TG concentrations (P < 0.001) by 3 mo, which were sustained to 12 mo, with no effect on BDNF. Changes in plasma EPA and DHA and urinary flavonoid metabolite concentrations confirmed compliance to the intervention. ConclusionsThese results suggest that cosupplementation with ω-3 PUFAs and cocoa flavanols for 12 mo does not improve cognitive outcomes in those with cognitive impairment.This trial was registered at clinicaltrials.gov as NCT02525198.

Novel 13C enrichment technique reveals early turnover of DHA in peripheral tissues

The brain is rich in DHA, which plays important roles in regulating neuronal function. Recently, using compound-specific isotope analysis that takes advantage of natural differences in carbon-13 content (13C/12C ratio or δ13C) of the food supply, we determined the brain DHA half-life. However, because of methodological limitations, we were unable to capture DHA turnover rates in peripheral tissues. In the current study, we applied compound-specific isotope analysis via high-precision GC combustion isotope ratio mass spectrometry to determine half-lives of brain, liver, and plasma DHA in mice following a dietary switch experiment. To model DHA tissue turnover rates in peripheral tissues, we added earlier time points within the diet switch study and took advantage of natural variations in the δ13C-DHA of algal and fish DHA sources to maintain DHA pool sizes and used an enriched (uniformly labeled 13C) DHA treatment. Mice were fed a fish-DHA diet (control) for 3 months, then switched to an algal-DHA treatment diet, the 13C enriched-DHA treatment diet, or they stayed on the control diet for the remainder of the study time course. In mice fed the algal and 13C enriched-DHA diets, the brain DHA half-life was 47 and 46 days, the liver half-life was 5.6 and 7.2 days, and the plasma half-life was 4.7 and 6.4 days, respectively. By using improved methodologies, we calculated DHA turnover rates in the liver and plasma, and our study for the first time, by using an enriched DHA source (very high δ13C), validated its utility in diet switch studies.

AA and DHA are decreased in paediatric AD/HD and inattention is ameliorated by increased plasma DHA

AA and DHA are decreased in paediatric AD/HD and inattention is ameliorated by increased plasma DHA

Association between blood N-3 fatty acid levels and the risk of coronavirus disease 2019 in the UK Biobank

BackgroundThe role of nutritional status and the risk of contracting and/or experiencing adverse outcomes from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are unclear. Preliminary studies suggest that higher n-3 PUFA intakes are protective. ObjectivesThis study aimed to compare the risk of 3 coronavirus disease 2019 (COVID-19) outcomes (testing positive for SARS-CoV-2, hospitalization, and death) as a function of the baseline plasma DHA levels. MethodsThe DHA levels (% of total fatty acids [FAs]) were measured by nuclear magnetic resonance. The 3 outcomes and relevant covariates were available for 110,584 subjects (hospitalization and death) and for 26,595 ever-tested subjects (positive for SARS-CoV-2) in the UK Biobank prospective cohort study. Outcome data between 1 January, 2020, and 23 March, 2021, were included. The Omega-3 Index (O3I) (RBC EPA + DHA%) values across DHA% quintiles were estimated. The multivariable Cox proportional hazards models were constructed, and linear (per 1 SD) relations with the risk of each outcome were computed as HRs. ResultsIn the fully adjusted models, comparing the fifth to the first DHA% quintiles, the HRs (95% confidence intervals) for testing positive, being hospitalized, and dying with COVID-19 were 0.79 (0.71, 0.89, P < 0.001), 0.74 (0.58, 0.94, P < 0.05), and 1.04 (0.69–1.57, not significant), respectively. On a per 1-SD increase in DHA% basis, the HRs for testing positive, hospitalization, and death, were 0.92 (0.89, 0.96, P < 0.001), 0.89 (0.83, 0.97, P < 0.01), and 0.95 (0.83, 1.09), respectively. The estimated O3I values across DHA quintiles ranged from 3.5% (quintile 1) to 8% (quintile 5). ConclusionsThese findings suggest that nutritional strategies to increase the circulating n-3 PUFA levels, such as increased consumption of oily fish and/or use of n-3 FA supplements, may reduce the risk of adverse COVID-19 outcomes.

Carbon Isotope Ratios of Plasma and RBC Fatty Acids Identify Meat Consumers in a 12-Week Inpatient Feeding Study of 32 Men

Molecular stable isotope ratios are a novel type of dietary biomarker with high sensitivity and specificity for certain foods. Among these, fatty acid carbon isotope ratios (CIRs) have strong potential but have not been investigated as dietary biomarkers. We evaluated whether fatty acid CIRs and mass proportions were associated with meat, fish, and sugar-sweetened beverage (SSB) intake. Thirty-two men [aged 46.2±10.5 y; BMI (kg/m2): 27.2±4.0] underwent a 12-wk inpatient dietary intervention at the National Institute of Diabetes and Digestive and Kidney Diseases in Phoenix, Arizona. Men were randomly assigned to 1 of 8 dietary treatments varying the presence/absence of dietary meat, fish, and SSBs in all combinations. Fatty acid CIRs and mass proportions were measured in fasting blood samples and adipose tissue biopsies that were collected pre- and postintervention. Dietary effects were analyzed using multivariable regression and receiver operating characteristic AUCs were calculated using logistic regression. CIRs of the several abundant SFAs, MUFAs and arachidonic acid (20:4n-6) in plasma were strongly associated with meat, as were a subset of these fatty acids in RBCs. Effect sizes in plasma ranged from 1.01‰ to 1.93‰ and were similar but attenuated in RBCs. Mass proportions of those fatty acids were not associated with diet. CIRs of plasma dihomo-γ-linolenic acid (20:3n-6) and adipose palmitic acid (16:0) were weakly associated with SSBs. Mass proportions of plasma odd-chain fatty acids were associated with meat, and mass proportions of plasma EPA and DHA (20:5n-3 and 22:6n-3) were associated with fish. CIRs of plasma and RBC fatty acids show promise as sensitive and specific measures of dietary meat. These provide different information from that provided by fatty acid mass proportions, and are informative where mass proportion is not. This trial is registered at www.clinicaltrials.gov as NCT01237093.

Choline, DHA, and Diarrheal Disease Associated with Growth Faltering in a Case-Control Study

ABSTRACTBackgroundChildren with recurrent infectious diarrhea are susceptible to growth faltering. DHA and choline may play a role in this relationship due to their involvement in lipid metabolism, gut immunity, and inflammatory pathways.ObjectivesThis study aimed to characterize the contributions made by DHA and choline status and enteric damage in young children in the association between diarrheal illness and child growth.MethodsA longitudinal case-control study was conducted among children aged 6–36 mo (N = 195) in Cap-Haitien, Haiti. Mother-child dyads were recruited from community health posts and outpatient clinics. Cases were defined as children experiencing acute diarrhea within the last 3 d and matched to healthy controls. Child anthropometry, dietary intake, and blood and stool samples were collected at baseline and follow-up. Plasma DHA, choline, and betaine were determined by LC-MS/MS methods (n = 49) and intestinal fatty acid–binding protein (I-FABP) by ELISA (n = 183). Multivariate regression models were applied with mediation analyses to examine associations and adjust for confounding factors.ResultsAt baseline, mean plasma DHA concentrations (1.03 µg/mL; 95% CI: 0.91, 1.15) were not significantly different between cases and controls, nor was there a difference in mean plasma choline concentrations (4.5 µg/mL; 95% CI: 3.8, 5.1). Mean plasma I-FABP concentrations were significantly higher at follow-up in cases (3.34; 95% CI: 3.28, 3.40) than controls (3.20; 95% CI: 3.13, 3.27; P = 0.002). In adjusted multilinear regression models, higher plasma DHA concentrations at follow-up were associated with a negative change in weight-age z score (P = 0.016), and follow-up I-FABP was inversely associated with height-age z score (P = 0.035). No interaction or mediation effects were found.ConclusionsI-FABP concentrations were significantly higher in cases as compared with controls at follow-up, suggesting ongoing enteric damage and increased risk for malnutrition. Plasma DHA and I-FABP may have a role in childhood growth outcomes.

ω-3 polyunsaturated fatty acid supplementation improves postabsorptive and prandial protein metabolism in patients with chronic obstructive pulmonary disease: a randomized clinical trial

Disturbances in protein metabolism and impaired muscle health have been observed in chronic obstructive pulmonary disease (COPD). The ω-3 (n-3) PUFAs EPA and DHA are known for their anti-inflammatory and muscle health-enhancing properties. We examined whether daily EPA+DHA supplementation can improve daily protein homeostasis in patients with COPD by reducing postabsorptive whole-body protein breakdown (PB) and enhancing the anabolic response to feeding in a dose-dependent way. Normal-weight participants with moderate to severe COPD (n=32) received daily for 4 wk, according to a randomized double-blind placebo controlled 3-group design, a high dose (3.5g, n=10) of EPA+DHA, a low dose (2.0g, n=10) of EPA+DHA, or placebo (olive oil, n=12) via gel capsules. At pre- and postintervention, stable isotope tracers were infused to assess postabsorptive netPB [postabsorptive PB - protein synthesis (PS)] and the anabolic response (prandial netPS=prandial PS-PB) to a protein meal. In addition, muscle mass and function were measured. Plasma phosphatidylcholine EPA and DHA concentrations were higher after 4 wk of supplementation in both EPA+DHA groups (P<0.004), and there was a trend toward higher values for plasma EPA after the high compared with the low dose of EPA+DHA (P=0.065). Postabsorptive PB was lower after 4 wk of the high dose of EPA+DHA, whereas netPB was lower independent of the dose of EPA+DHA (low dose, P=0.037; high dose, P=0.026). Prandial netPS was increased only after the high dose of EPA+DHA (P=0.03). Extremity lean mass but not muscle function was increased, independent of the EPA+DHA dose (P<0.05). Daily n-3 PUFA supplementation for 4 wk induces a shift toward a positive daily protein homeostasis in patients with COPD in part in a dose-dependent way. Daily doses up to 3.5g EPA and DHA are still well tolerated and lead to protein gain in these patients. This trial was registered at clinicaltrials.gov as NCT01624792.

Pharmacokinetics of a Single Intake of a Self-Emulsifying Drug Delivery System Containing the Triglyceride Form of DHA: A Randomized, Double-Blinded, Crossover Study

ABSTRACTBackgroundThe health benefits of n–3 (ω-3) PUFAs are well studied. A self-emulsifying drug delivery system (SEDDS) is expected to improve n–3 PUFA absorption.ObjectivesThe present study investigated how a single ingestion of a new SEDDS containing the triglyceride (TG) form of DHA (22:6n–3) (DHA/TG) would affect the plasma DHA concentration in healthy participants.MethodsFifteen healthy participants (age: 20–65 y; BMI: 18.5–25 kg/m2) were enrolled in this randomized, double-blind, crossover study. Participants in a fasting state consumed a single dose of 920 mg DHA and 80 mg EPA (20:5n–3) in SEDDS soft capsules (SEDDS capsule) or non-emulsifying soft capsules (control capsule). Blood was sampled at 0, 1.5, 3, 5, 7, and 9 h after dosing. The primary outcome was the baseline-adjusted incremental AUC (iAUC) for plasma DHA concentrations (iAUC_DHA).ResultsThe iAUC_DHA was significantly higher for the SEDDS capsule (147.9 ± 15.8 µg·h/mL) than for the control capsule (106.4 ± 18.1 µg·h/mL) (P = 0.018; SEDDS/control ratio: 1.4:1). However, plasma EPA concentrations and iAUC values did not significantly differ between the SEDDS and control capsules. Cmax was significantly higher with the SEDDS capsule for both DHA (P = 0.019) and EPA (P = 0.012) than with the control capsule.ConclusionsThese results suggest that a SEDDS improves the absorbability of DHA/TG in healthy participants. This indicates that SEDDS capsules would be beneficial for efficient ingestion of DHA.This trial was registered at https://www.umin.ac.jp/ctr/ as UMIN000044188.

Link between Omega 3 Fatty Acids Carried by Lipoproteins and Breast Cancer Severity.

According to the International Agency for Research on Cancer (IARC) more than 10% of cancers can be explained by inadequate diet and excess body weight. Breast cancer is the most common cancer affecting women. The goal of our study is to clarify the relationship between ω3 fatty acids (FA) carried by different lipoproteins and breast cancer (BC) severity, according to two approaches: through clinic-biological data and through in vitro breast cancer cell models. The clinical study has been performed in sera from a cohort of BC women (n = 140, ICO, France) whose tumors differed by their hormone receptors status (HR− for tumors negative for estrogen receptors and progesterone receptors, HR+ for tumors positive for either estrogen receptors or progesterone receptors) and the level of proliferation markers (Ki-67 ≤ 20% Prolif− and Ki-67 ≥ 30% Prolif+). Lipids and ω3FA have been quantified in whole serum and in apoB-containing lipoproteins (Non-HDL) or free of it (HDL). Differences between Prolif− and Prolif+ were compared by Wilcoxon test in each sub-group HR+ and HR−. Results are expressed as median [25th–75th percentile]. Plasma cholesterol, triglycerides, HDL-cholesterol and Non-HDL cholesterol did not differ between Prolif− and Prolif+ sub-groups of HR− and HR+ patients. Plasma EPA and DHA concentrations did not differ either. In the HR− group, the distribution of EPA and DHA between HDL and Non-HDL differed significantly, as assessed by a higher ratio between the FA concentration in Non-HDL and HDL in Prolif− vs. Prolif+ patients (0.20 [0.15–0.36] vs. 0.04 [0.02–0.08], p = 0.0001 for EPA and 0.08 [0.04–0.10] vs. 0.04 [0.01–0.07], p = 0.04 for DHA). In this HR− group, a significant increase in Non-HDL EPA concentration was also observed in Prolif− vs. Prolif+ (0.18 [0.13–0.40] vs. 0.05 [0.02–0.07], p = 0.001). A relative enrichment on Non-HDL in EPA and DHA was also observed in Prolif− patients vs. Prolif+ patients, as assessed by a higher molar ratio between FA and apoB (0.12 [0.09–0.18] vs. 0.02 [0.01–0.05], p < 0.0001 for EPA and 1.00 [0.73–1.69 vs. 0.52 [0.14–1.08], p = 0.04 for DHA). These data were partly confirmed by an in vitro approach of proliferation of isolated lipoproteins containing EPA and DHA on MDA-MB-231 (HR−) and MCF-7 (HR+) cell models. Indeed, among all the studied fractions, only the correlation between the EPA concentration of Non-HDL was confirmed in vitro, although with borderline statistical significance (p = 0.07), in MDA-MB-231 cells. Non-HDL DHA, in the same cells model was significantly correlated to proliferation (p = 0.04). This preliminary study suggests a protective effect on breast cancer proliferation of EPA and DHA carried by apo B-containing lipoproteins (Non-HDL), limited to HR− tumors.

Effects of Individual Circulating FFAs on Plasma Oxylipin Levels: Implications for FFA Epoxide‐diol Ratios as Indices of Soluble Epoxide Hydrolase Activity

Oxylipins, oxidation products of essential free fatty acids (FFAs), are involved in various cellular signaling. Among them, FFA epoxides are associated with beneficial effects in metabolic and cardiovascular health. FFA epoxides are metabolized to usually biologically less active diols by soluble epoxide hydrolase (sEH). Inhibition of sEH, which increases FFA epoxides, improves glucose homeostasis and cardiovascular health. Plasma epoxide‐diol ratios have been used as indices of sEH activity.Objective and HypothesisThe objective of this study was to examine the effects of acute elevation of plasma FFAs on oxylipins, particularly, epoxides, diols, and their ratios. We tested if FFA epoxide‐diol ratios are altered by circulating FFA levels (i.e., substrate availability) independent of sEH activity.MethodsMale Wistar rats received a constant intravenous infusion of olive (70% oleic acid [OA]), safflower seed (72% linoleic acid [LA]), and fish (rich in w‐3 FFAs) oils (20% wt/vol emulsion, 0.5 ml/h; n = 6 for each infusion) for 2 hours to selectively raise OA, LA, and w‐3 FFAs (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]), respectively. Blood samples were collected before and after the infusions and analyzed for oxylipins using LC‐MS and individual FFAs using GC‐MS. As LA, DHA, and EPA are metabolized to epoxides and diols, we evaluated their mass‐action effects to alter epoxides, diols, or their ratios. In contrast, OA is not metabolized to epoxides and diols detected in our assays, and the olive oil infusion served as control for any non‐mass‐action effects.ResultsAs expected, olive, safflower seed, and fish oil infusions selectively raised plasma OA (57%), LA (87%), and EPA (70%) and DHA (54%), respectively (P &lt; 0.05 for all). Interestingly, olive oil infusion had significant effects to decrease FFA epoxides and diols with more dramatic effects on epoxides than diols (P &lt; 0.01), resulting in large (up to 6‐fold) increases in diol‐to‐epoxide ratios. We found similar effects with safflower seed and fish oil infusions, although these infusions also showed mass action effects to increase epoxide and diol levels derived from LA (safflower seed oil) and DHA and EPA (fish oil). The decreases in FFA epoxides with acute elevation of circulating FFAs (i.e., increased substrate availability) were unexpected and appeared to be due to increased epoxide metabolism independent of sEH. We are currently examining the possibility that acute elevation of plasma FFAs stimulates glucuronidation of FFA epoxides to increase their removal via urinary excretion.ConclusionsRaising plasma FFAs has profound effects to decrease plasma FFA epoxides, significantly altering plasma epoxide‐diol ratios. These data suggest that caution should be taken in comparing epoxide‐diol ratios, as indices of sEH activity, between conditions with different circulating FFA levels. Our data also suggest that plasma FFAs regulate epoxide levels by stimulating a metabolic process independent of sEH, possibly glucuronidation followed by renal excretion.

DHA turnover in pregnant women using the natural abundance variation of 13C: a pilot study.

The importance of DHA intake to support fetal development and maternal health is well established. In this pilot study we applied the natural abundance approach to determine the contribution of 200 mg/day of DHA supplement to the plasma DHA pool in 19 healthy pregnant women on a free diet.Women received DHA, from pregnancy week 20 until delivery, from an algal source (N=13, Algae group) or from fish oil (N=6, Fish group) with slightly different content of 13C.We measured plasma phospholipids DHA 13C:12C ratio (reported as δ13C) prior to supplementation (T0), after 10 (T1) and 90 days (T2) and prior to delivery (T3).The δ13C of DHA in algae and fish supplements were -15.8±0.2 mUr and -25.3±0.2 mUr (p<0.001).DHA δ13C in the Algae group increased from -27.7±1.6 mUr (T0) to -21.9±2.2 mUr (T3) (p<0.001), whereas there were not significant changes in the Fish group (-27.8±0.9 mUr at T0 and -27.3±1.1 mUr at T3, p=0.09).In the Algae group 200 mg/day of DHA contributed to the plasma phospholipid pool by a median value of 53% (31-75% minimum and maximum). This estimation was not possible in the fish group.Our results demonstrate the feasibility of assessing the contribution of DHA from an algal source to the plasma DHA pool in pregnant women by the natural abundance approach. Plasma δ13C DHA did not change when consuming DHA of fish origin, with almost the same δ13C value of that of the pre-supplementation plasma δ13C DHA.

Lutein and docosahexaenoic acid enriched egg consumption improves retina function in healthy Caucasian older adults

• A full-field electroretinogram was used to assess changes in retina function. • Lutein and DHA enriched eggs significantly increased plasma DHA concentrations. • Lutein and DHA enriched eggs improved rod and cone driven bipolar cell function. • Two eggs daily for six weeks did not adversely impact plasma blood lipid parameters. The purpose of this research was to investigate whether the consumption of lutein and DHA enriched eggs can improve visual function among older adults at risk of age-related eye disease. A total of 30 Caucasian older adults (64.0 ± 3.4 years) consumed enriched eggs (0.87 mg lutein/day, 220 mg DHA/day) daily for 6-weeks. Retina function was assessed by full-field electroretinogram along with plasma DHA, plasma lutein, lipid profiles, and lipoprotein subfractions at day 0 (PRE) and 6 weeks (POST). At POST, maximum amplitude of scotopic a-wave and photopic b-wave significantly increased ( P < 0.001); and plasma DHA levels increased by 35.4% ( P < 0.001). Plasma lipid parameters, lutein and LDL sub-fractions remained unchanged, with a significant increase in large HDL particles and a decrease in intermediate sized HDL particles. Overall, the consumption of two lutein and DHA enriched eggs daily improves electrophysiological retina function without adversely altering plasma lipids in Caucasian older adults.