Plasma Plasma Phosphatidylcholine Research Articles

Models predict change in plasma triglyceride concentrations and long-chain n-3 polyunsaturated fatty acid proportions in healthy participants after fish oil intervention.

Substantial response heterogeneity is commonly seen in dietary intervention trials. In larger datasets, this variability can be exploited to identify predictors, for example genetic and/or phenotypic baseline characteristics, associated with response in an outcome of interest. Using data from a placebo-controlled crossover study (the FINGEN study), supplementing with two doses of long chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs), the primary goal of this analysis was to develop models to predict change in concentrations of plasma triglycerides (TG), and in the plasma phosphatidylcholine (PC) LC n-3 PUFAs eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA), after fish oil (FO) supplementation. A secondary goal was to establish if clustering of data prior to FO supplementation would lead to identification of groups of participants who responded differentially. To generate models for the outcomes of interest, variable selection methods (forward and backward stepwise selection, LASSO and the Boruta algorithm) were applied to identify suitable predictors. The final model was chosen based on the lowest validation set root mean squared error (RMSE) after applying each method across multiple imputed datasets. Unsupervised clustering of data prior to FO supplementation was implemented using k-medoids and hierarchical clustering, with cluster membership compared with changes in plasma TG and plasma PC EPA + DHA. Models for predicting response showed a greater TG-lowering after 1.8 g/day EPA + DHA with lower pre-intervention levels of plasma insulin, LDL cholesterol, C20:3n-6 and saturated fat consumption, but higher pre-intervention levels of plasma TG, and serum IL-10 and VCAM-1. Models also showed greater increases in plasma PC EPA + DHA with age and female sex. There were no statistically significant differences in PC EPA + DHA and TG responses between baseline clusters. Our models established new predictors of response in TG (plasma insulin, LDL cholesterol, C20:3n-6, saturated fat consumption, TG, IL-10 and VCAM-1) and in PC EPA + DHA (age and sex) upon intervention with fish oil. We demonstrate how application of statistical methods can provide new insights for precision nutrition, by predicting participants who are most likely to respond beneficially to nutritional interventions.

Short communication: Effects of dietary deoiled soy lecithin supplementation on circulating choline and choline metabolites, and the plasma phospholipid profile in Holstein cows fed palm fat

Dietary lecithin is a source of choline. Our objective was to evaluate the effects of dietary deoiled soy lecithin feeding on circulating choline, choline metabolites, and the plasma phospholipid profile in lactating dairy cows fed fractionated palm fatty acids. In a split-plot Latin square design, 16 Holstein cows (160 ± 7 d in milk; 3.6 ± 1.2 parity) were randomly allocated to a main plot receiving a corn silage and alfalfa haylage-based diet with palm fat containing either moderate or high palmitic acid content at 1.75% of ration dry matter (moderate and high palmitic acid containing 72 or 99% palmitic acid in fat supplement, respectively; n = 8/palm fat diet). Within each palm fat group, deoiled soy lecithin was top-dressed at 0, 0.12, 0.24, or 0.36% of ration dry matter in a replicated 4 × 4 Latin square design with 14-d experimental periods. A 14-d covariate period was used to acclimate cows to palm fat feeding without lecithin supplementation. Blood sampling occurred during the final 3 d of each experimental period. Plasma choline and choline metabolites were quantified using liquid chromatography and mass spectrometry. Plasma phospholipids were profiled using time-of-flight mass spectrometry. Whereas no effects of treatments were detected for plasma choline or methionine, lecithin feeding increased the plasma concentrations of choline metabolites trimethylamine N-oxide and dimethylglycine (24 and 11%, respectively). Plasma phosphatidylcholine (PC) and sphingomyelin (SM) concentrations increased with deoiled lecithin feeding (e.g., PC 16:0/22:6 and SM d18:1/18:3). Lecithin supplementation also increased plasma lysophosphatidylcholine (LPC) concentrations (e.g., LPC 18:0) while reducing plasma phosphatidylethanolamine (PE) concentrations (e.g., PE 16:0/20:5). Although increases in microbial-derived trimethylamine N-oxide suggest gastrointestinal lecithin degradation, elevations in plasma dimethylglycine, PC, LPC, and SM suggest that choline availability was improved by lecithin feeding in cows, thus supporting enhanced endogenous phospholipid synthesis.

Fatty acid composition of adipose tissue at term indicates deficiency of arachidonic and docosahexaenoic acid and excessive linoleic acid supply in preterm infants

BackgroundArachidonic (ARA) and docosahexaenoic acid (DHA) are constitutive to membrane phospholipids, and essential for brain and overall development. ARA/DHA pools in term infants (TI) are built during the third trimester, stored as adipose tissue triglycerides and predominantly distributed via plasma phosphatidylcholine (PC). In preterm infants (PTI), placental ARA/DHA supply is replaced by linoleic-acid (LA)-enriched nutrition. This study aimed to investigate the impact of PTI nutrition, compared to placental supply, on fatty acid composition in adipose tissue and blood.MethodsProspective observational study (4/2017–3/2019) in 12 PTI and 3 PTI with enterostomy (PTI/E) (gestational age (GA) < 32 weeks) with surgical intervention at term (± 6 weeks) and 14 TI (GA ≥ 34 weeks, surgical intervention < 2 weeks postnatally). PTI/E were analyzed descriptively only. PC and triglyceride fatty acids were analyzed with tandem mass spectrometry and gas chromatography, respectively. Results were compared between TI and PTI with Wilcoxon Test and shown as median [25th percentile–75th percentile] mol%.ResultsPTI had less ARA in adipose tissue TG (0.77[0.67–0.87]% vs. 1.04[0.95–1.14]%, p = 0.0003) and plasma PC (20.7[18.7–22.8]% vs. 28.3[22.7–33.5]%, p = 0.011) than TI. PTI also had less DHA in adipose tissue TG (0.6[0.4–0.8]% vs. 1.1[0.8–1.4]%, p = 0.006) and plasma PC (6.4[5.6–7.1]% vs. 8.4[7.8–13.1]%, p = 0.002). LA was increased in PTI’s adipose tissue TG (10.0[8.8–12.3]% vs. 3.0[2.5–3.6]%, p < 0.0001) and plasma PC (48.4[44.6–49.6]% vs. 30.6[24.9–35.6]%, p = 0.0002). Similar differences were observed in erythrocyte PC.ConclusionIn PTI, LA is increased and ARA/DHA decreased in adipose tissue, plasma and erythrocyte lipids as proxies for other tissues, likely caused by PTI nutrition. This may contribute to impaired PTI development.

Effect of supplementation with flaxseed oil and different doses of fish oil for 2 weeks on plasma phosphatidylcholine fatty acids in young women

Background/objectivesAlthough assumed, it remains unclear that fatty acid (FA) biomarkers of n-3 long-chain PUFA reflect wide ranges of intake. However, to be utilised as biomarkers, to predict dietary intake, dose–response curves that cover a spectrum of intakes are required. The aim of the study was to investigate whether the FA composition of plasma phosphatidylcholine (PC) is a sensitive biomarker of n-3 FAs from fish oil, across a range of supplementation doses, and alpha-linolenic acid (ALA) supplementation, in young, healthy women.Subjects/methodsA total of 303 young women were randomised to intakes ranging between 0.33 and 4.50 g EPA+DHA/day from fish oil (not all doses used in each year) or flaxseed oil (5.90–6.60 g/d) daily for 14 days in a series of trials, over 5 years. Fasting blood was collected at baseline (day 0) and day 14 and plasma PC FA composition, total and HDL-cholesterol and triglyceride concentrations measured.ResultsFourteen days supplementation with fish oil significantly (P < 0.01) increased, in a dose-dependent fashion, plasma PC EPA, DPA and DHA at all doses except 1 and 3 mL/day. For the combined group of women who consumed any fish oil there was a 16% (P < 0.01) decrease in plasma triacylglycerol concentrations after 14 days supplementation. Flaxseed oil supplementation for 14 day resulted in significant (P < 0.01) increases in ALA, EPA and DPA, whilst DHA remained unchanged.ConclusionOur data demonstrate plasma PC is a sensitive biomarker of n-3 FA intake and reflects changes within 14 days across a range of intakes.

Abnormal liver phosphatidylcholine synthesis revealed in patients with acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is associated with a severe pro-inflammatory response; although decreased plasma cholesterol concentration has been linked to systemic inflammation, any association of phospholipid metabolic pathways with ARDS has not been characterized. Plasma phosphatidylcholine (PC), the major phospholipid of circulating lipoproteins, is synthesized in human liver by two biologically diverse pathways: the cytidine diphosphocholine (CDP):choline and phosphatidylethanolamine N-methyltransferase (PEMT) pathways. Here, we used ESI-MS/MS both to characterize plasma PC compositions and to quantify metabolic fluxes of both pathways using stable isotopes in patients with severe ARDS and in healthy controls. Direct incorporation of methyl-D9-choline estimated CDP:choline pathway flux, while PEMT flux was determined from incorporations of one and two methyl-D3 groups derived from methyl-D9-choline. The results of MS/MS analysis showed significant alterations in plasma PC composition in patients with ARDS versus healthy controls. In particular, the increased overall methyl-D9-PC enrichment and, most importantly, the much lower methyl-D3-PC and methyl-D6-PC enrichments suggest increased flux through the CDP:choline pathway and reduced flux through the PEMT pathway in ARDS. To our knowledge, this study is the first to demonstrate significant plasma PC molecular compositional changes combined with associated alterations in the dynamics of PC synthetic pathways in patients with ARDS.

Fatty Acid Composition of Plasma Phosphatidylcholine Determines Body Fat Parameters in Subjects with Metabolic Syndrome-Related Traits

This study examines the associations of fatty acids (FAs) in plasma phosphatidylcholine (PC) with the anthropometrical and biochemical characteristic of patients with metabolic syndrome (MetS)-related traits. We analyzed the FA profiles of PC in 300 persons with MetS-related traits (152 M/148F, mean age 46.9 ± 9.0 years) and in 70 healthy controls of the same age using a balanced men/women ratio and gas-liquid chromatography. Multivariate linear regression analysis was performed to determine the coefficients of determination (R2) using FA proportions of the mentioned proband characteristics. The FA composition of PC in patients with MetS traits was only associated with waist circumference (R2 = 0.27), waist-to-hip ratio (WHR; R2 = 0.41), body fat percentage (R2 = 0.62), and fat mass (R2 = 0.29). Positive associations were found for dihomo-γ-linolenic (DGLA), palmitic, stearic (SA), α-linolenic (ALA), and eicosapentaenoic acids, whereas negative associations were found for linoleic (LA), oleic, and docosapentaenoic acids. Palmitoleic acid (POA) was positively associated with waist circumference but negatively with fat percentage. In controls, significant associations were found for waist circumference (R2 = 0.51), WHR (R2 = 0.53), body fat percentage (R2 = 0.60), and fat mass (R2 = 0.34). DGLA and saturated FA (SFA) were positively associated, whereas docosahexaenoic, adrenic, and cis-vaccenic acids were negatively associated. The study group differed from controls as follows: lower concentrations of LA and total n-6 FA, higher indices of delta-9-desaturase and delta-6 desaturase activity and higher proportions of POA, SA, ALA, DGLA, and SFA. We found significant associations (R2 >0.25) of FA in plasma PC with adiposity in middle-aged persons with MetS-related traits, but not with metabolic indices.

Complex Relation Between Diet and Phospholipid Fatty Acids in Children With Cystic Fibrosis

Altered total plasma n-6 and n-3 fatty acids are common in cystic fibrosis (CF). Whether alterations extend to plasma phosphatidylcholine (PC) and phosphatidylethanolamine (PE) and are explained by diet is unclear. The present study was to describe the dietary intake of a large group of children with CF and to determine whether dietary fat composition explains differences in plasma PC and PE fatty acids between children with and without CF. Dietary intake was assessed using a food frequency questionnaire. Venous blood was collected. Plasma PC and PE were separately analyzed for fatty acids. Children with CF, n = 74, consumed more calories and fat (g/day and % energy), with significantly more saturates mainly from dairy foods and less polyunsaturates including linoleic acid (LA), arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) (% fat) than reference children, n = 71. A subset of children with CF, not differing in dietary intake from the larger group, had significantly lower LA and DHA, but higher EPA in plasma PC and had higher LA and lower ARA and DHA in plasma PE, compared to a subset of reference children. In both groups, LA intake and LA in plasma PC and PE were not associated. EPA and DHA intakes were positively associated with EPA and DHA, respectively, in plasma PC, but not PE, in reference children only. The fatty acid composition of plasma PC and PE is altered in CF. Fatty acid differences between children with and without CF are inconsistent between PC and PE and are not explained by dietary fat.

Plasma Phosphatidylcholines Fatty Acids in Men with Squamous Cell Esophageal Cancer: Chemoradiotherapy Improves Abnormal Profile.

BackgroundAbnormal metabolism of fatty acids (FA) is considered to play a role in human cancers, including esophageal cancer (EC). Nevertheless, there have been only a few studies dealing with the influence of the chemotherapy or radiotherapy on the plasma FA profiles. In this work we compared FA in plasma phosphatidylcholine (PC) of the patients with squamous EC and healthy subjects and investigated changes in the FA spectrum during neoadjuvant chemoradiotherapy (CRT).Material/MethodsForty-two men with squamous EC were compared with age-matched healthy controls. The EC group was subjected to concurrent neoadjuvant CRT. We analyzed FA in plasma PC before and after CRT.ResultsThe EC group was characterized by increased levels of both saturated and monounsaturated FA, associated with an increased index of SCD1 (stearoyl-CoA desaturase-1). Moreover, decreased levels of linoleic acid and total polyunsaturated FA (PUFA) n-6 were found in EC patients. The CRT was accompanied by increased docosahexaenoic acid and total PUFA n-3 content in plasma PC, concurrently with the decrease of estimated activity of SCD1.ConclusionsWe found that patients with EC had altered FA profile in plasma PC, which could be related to abnormal FA metabolism in cancer (e.g., altered synthesis de novo, β-oxidation, desaturation, and elongation). The described changes in FA profiles during CRT could be involved in favorable functioning of CRT. Further studies investigating the plasma FA compositions and their changes due to CRT in EC patients are warranted.

The impact of an omega-3 fatty acid rich lipid emulsion on fatty acid profiles in critically ill septic patients

BackgroundDeath from sepsis in the intensive therapy unit (ITU) is frequently preceded by the development of multiple organ failure as a result of uncontrolled inflammation. Treatment with omega-3 (n−3) fatty acids (FAs), principally eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has been demonstrated to attenuate the effects of uncontrolled inflammation and may be clinically beneficial in reducing mortality from organ dysfunction. Fish oil (FO) is a source of EPA and DHA. MethodsA randomized trial investigating the effects of parenteral (intravenous) nutrition providing FO (0.092g EPA+DHA/kg body weight/day) was conducted. Sixty consecutive ITU patients diagnosed with sepsis were randomised to receive either once daily parenteral FO and standard medical care or standard medical care only. ResultsForty one patients (21 received fish oil; 20 controls) consented to blood sampling and blood was taken on days 0, 1, 2, 3, 5, 7, 10 and 13; because of deaths, patient discharge and withdrawal of consent, the number of blood samples available for analysis diminished with time. FA composition of plasma phosphatidylcholine (PC), plasma non-esterified FAs (NEFAs) and peripheral blood mononuclear cells (PBMCs) was determined by gas chromatography. EPA and DHA were rapidly incorporated into all 3 lipid pools investigated. There was a reduction in the arachidonic acid (AA) to EPA+DHA ratio in plasma PC and NEFAs. Fewer patients died in the FO group (13.3% (n=4)) compared with the control group (26.7% (n=8)) but this difference was not significant. A reduction in the AA/(EPA+DHA) ratio in PBMCs and plasma PC was associated with significantly improved survival. Plasma PC, plasma NEFA and PBMC FA profiles are rapidly altered by FO infusion in critically ill septic patients. ConclusionThe provision of high dose n−3 FAs resulted in a rapid and significant increase in EPA and DHA and a reduction in AA/(EPA+DHA) ratio. This latter reduction is associated with improved survival.

Bioavailability of long chain omega-3 polyunsaturated fatty acids from phospholipid-rich herring roe oil in men and women with mildly elevated triacylglycerols

This randomized, single-blind, crossover trial assessed the bioavailability of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and docosapentaenoic acid (DPA) from two different sources, each examined over a 12h period following consumption of a single serving and after 2-weeks of daily supplementation. Thirty-two adults with fasting triacylglycerol (TAG) concentrations between 100 and 399mg/dL were randomly assigned, with stratification by sex and age, to receive 12 capsules/day containing either phospholipid (PL)-rich herring roe oil (Romega® 30, 628mg/day EPA; 1810mg/day DHA; 137mg/day DPA) or TAG-rich fish oil (575mg/day EPA; 1843mg/day DHA; 259mg/day DPA) each for a 2-week period separated by a 4 week washout. The net incremental area under the curve from 0 to 12h for EPA, DHA, and EPA+DHA in plasma phosphatidylcholine (PC) were significantly higher (p<0.01 for all) after Romega 30 supplementation compared to fish oil. Similar results were observed when the data for the Romega 30 condition were normalized to fish oil EPA and DHA intakes (p<0.001 for all). After the 2-week supplementation period, fasting plasma PC EPA+ DHA was elevated by ~2.8 to 3.0-fold relative to baseline in both conditions (p<0.0001 for each), but there was no significant difference in the change from baseline (p=0.422) between Romega 30 (baseline=62.2±3.8µg/mL vs. end of study=172.9±11.7µg/mL) and fish oil (baseline=62.0±3.4µg/mL vs. end of study=185.4±11.2µg/mL) conditions. Similar results were observed for each individual LC n-3 PUFA in plasma PC after 2 weeks of supplementation. These data demonstrate that PL-rich herring roe is a well-tolerated and bioavailable source of LC n-3 PUFA.

No Clinical or Biochemical Evidence for Essential Fatty Acid Deficiency in Home Patients Who Depend on Long-Term Mixed Olive Oil- and Soybean Oil-Based Parenteral Nutrition.

Home parenteral nutrition (HPN) patients depend on lipid emulsions as part of their parenteral nutrition regimen to provide essential fatty acids (EFAs). Mixed-oil sources are used in modern lipid emulsions to decrease the amount of proinflammatory EFAs, mainly linoleic acid, which is present in large amounts in soybean oil. It is unknown whether patients who fully depend on such mixed lipids have adequate EFA supply. We therefore evaluated whether HPN patients who depend on mixed olive oil- and soybean oil-based HPN show clinical or biochemical evidence of EFA deficiency. Fatty acid status was assessed in plasma phosphatidylcholine (PC) and peripheral blood mononuclear cells from 30 patients receiving mixed olive oil- and soybean oil-based HPN (>3 months, ≥5 times per week) and 30 healthy controls. Innate immune cell functions were evaluated by assessing expression of surface membrane molecules, and reactive oxygen species, and cytokine production. None of the patients or controls showed clinical evidence (skin rash) or biochemical evidence (increased Holman index [>0.2]) for EFA deficiency. The Holman index in plasma PC (median [25th-75th percentile]) was significantly higher in patients (0.019 [0.015-0.028]) compared with controls (0.015 [0.011-0.017]). No differences were found in innate immune cell functions between groups, except for a 3.6-fold higher tumor necrosis factor-α production in patients. We found no clinical or biochemical evidence that HPN patients who fully and long-term depend on mixed olive oil- and soybean oil-based lipids have an increased risk for EFA deficiency.

Changes in plasma and erythrocyte omega-6 and omega-3 fatty acids in response to intravenous supply of omega-3 fatty acids in patients with hepatic colorectal metastases

BackgroundEicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are functionally the most important omega-3 polyunsaturated fatty acids (PUFAs). Oral supply of these fatty acids increases their levels in plasma and cell membranes, often at the expense of the omega-6 PUFAs arachidonic acid (ARA) and linoleic acid. This results in an altered pattern of lipid mediator production to one which is less pro-inflammatory. We investigated whether short term intravenous supply of omega-3 PUFAs could change the levels of EPA, DHA, ARA and linoleic acid in plasma and erythrocytes in patients with hepatic colorectal metastases.MethodsTwenty patients were randomised to receive a 72 hour infusion of total parenteral nutrition with (treatment group) or without (control group) omega-3 PUFAs. EPA, DHA, ARA and linoleic acid were measured in plasma phosphatidylcholine (PC) and erythrocytes at several times points up to the end of infusion and 5 to 12 days (mean 9 days) after stopping the infusion.ResultsThe treatment group showed increases in plasma PC EPA and DHA and erythrocyte EPA and decreases in plasma PC and erythrocyte linoleic acid, with effects most evident late in the infusion period. Plasma PC and erythrocyte EPA and linoleic acid all returned to baseline levels after the 5–12 day washout. Plasma PC DHA remained elevated above baseline after washout.ConclusionsIntravenous supply of omega-3 PUFAs results in a rapid increase of EPA and DHA in plasma PC and of EPA in erythrocytes. These findings suggest that infusion of omega-3 PUFAs could be used to induce a rapid effect especially in targeting inflammation.Trial registrationhttp://www.clinicaltrials.gov identifier NCT00942292

Fatty acids in plasma, white and red blood cells, and tissues after oral or intravenous administration of fish oil in rats

The importance of route of administration of omega-3 (n-3) polyunsaturated fatty acids (PUFA) (oral vs intravenous (iv)) is not clear. We determined the relative concentrations of fatty acids in plasma phosphatidylcholine (PC), red blood cells (RBC), white blood cells (WBC) and several tissues after short-term oral or iv administration of soybean oil (SO) or fish oil (FO). Wistar rats (n = 6/group) received saline, FO, or SO by gavage or saline, FO based-lipid emulsion (FLE), or SO based-lipid emulsion (SLE) iv. The oils were provided at 0.2 g/kg/day for three consecutive days. The animals were sacrificed 24 h after the last administration, blood was collected for plasma, WBC and RBC separation and tissues removed. Fatty acids were analysed by gas chromatography. FO resulted in higher eicosapentaenoic acid (EPA) in plasma PC and liver than the control. FLE resulted in higher EPA, docosahexaenoic acid (DHA) and total n-3 PUFA in plasma PC, WBC and liver than both the control and SLE groups. EPA, DHA and total n-3 PUFA were higher in the heart with FLE compared with SLE. Individual and total n-3 PUFA were higher in plasma PC, WBC, liver and heart with FLE than with FO given by gavage. Short-term iv administration of n-3 PUFA appears to be more effective at increasing EPA and DHA status in plasma, WBC, liver and heart than oral administration. This might be important for rapid treatment with n-3 PUFA.

Supplemental intravenous n-3 fatty acids and n-3 fatty acid status and outcome in critically ill elderly patients in the ICU receiving enteral nutrition

N-3 fatty acids (FA) may have benefits in ICU patients. The aims were to identify whether FA status is altered in critical illness and to evaluate the effect of supplemental intravenous n-3 FA on plasma FA status and clinical outcome in ICU patients receiving enteral nutrition. Enterally fed patients (n = 49; 60-80 years) were recruited in the first 48 h of ICU admission. Fifteen patients received n-3 FA emulsion (0.2 g/kg) over 6 h for 3 consecutive days, and 34 patients did not (control). Samples were collected before supplementation, and 24 and 72 h after the third infusion. Nineteen healthy elderly subjects were also studied; they gave a single blood sample. FA were measured in plasma phosphatidylcholine (PC). Critically ill patients had altered plasma PC FA compared with healthy elderly subjects. Surviving ICU patients had higher levels of docosahexaenoic acid and total n-3 FA and a lower ratio of n-6:n-3 FA in plasma PC than non-survivors. Infusion of n-3 FA increased eicosapentaenoic, docosahexaenoic and total n-3 FA, and decreased arachidonic and total n-6 FA and n-6:n-3 FA and arachidonic:eicosapentaenoic acid ratios. Gas exchange was enhanced 72 h after the third n-3 FA infusion (p = 0.001). Critically ill patients may have altered plasma FA profiles. A higher total n-3 FA and docosahexaenoic acid content in plasma PC is associated with survival and improved gas exchange.

Lower omega-3 fatty acid intake and status are associated with poorer cognitive function in older age: A comparison of individuals with and without cognitive impairment and Alzheimer's disease

ObjectivesVarious strands of evidence suggest that low intake of omega-3 fatty acids increases risk of cognitive decline and dementia. The present study investigated differences in dietary intake and blood plasma content of eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) in individuals with cognitive impairment no dementia (CIND), individuals with Alzheimer's disease (AD), and healthy volunteers (HV).MethodsA total of 135 individuals aged between 55 and 91 years (19 AD, 55 CIND, and 61 HV) were assessed predominantly within a hospital setting.ResultsCompared with age and sex-matched HV, individuals with AD or CIND performed poorly on a majority of tests of cognitive function. Impairment was greatest for delayed and verbal recognition memory. CIND individuals were less impaired than AD individuals. Omega-3 intake and the percentage of EPA and DHA in plasma phosphatidylcholine (PC) showed a similar pattern (AD < HV, with intermediate scores for CIND). Across the whole sample, and after controlling for age, years of education, level of socio-economic deprivation, and gender, omega-3 intake, plasma PC DHA, and plasma PC EPA were all significant positive predictors of memory functioning.DiscussionThese results are consistent with the possibility that omega-3 fatty acid nutrition has an impact on cognitive decline, but could equally be explained by dietary changes that occurred after onset of cognitive decline. It is also possible that the results could be explained by unknown confounding factors.

Plasma phosphatidylcholine concentrations of polyunsaturated fatty acids are differentially associated with hip bone mineral density and hip fracture in older adults: The framingham osteoporosis study

Polyunsaturated fatty acids (PUFAs) may influence bone health. The objective of this work was to examine associations between plasma phosphatidylcholine (PC) PUFA concentrations and hip measures: (1) femoral neck bone mineral density (FN-BMD) (n = 765); (2) 4-year change in FN-BMD (n = 556); and (3) hip fracture risk (n = 765) over 17-year follow-up among older adults in the Framingham Osteoporosis Study. BMD measures were regressed on quintile of plasma PC PUFAs (docosahexaenoic acid [DHA], linoleic acid [LA], and arachidonic acid [AA]), adjusted for covariates. Hazard ratios (HR) and 95% confidence interval (CI) for hip fracture were estimated by quintile of plasma PC PUFAs, adjusted for covariates. Higher concentrations of PC DHA were associated with loss of FN-BMD over 4 years in women (p-trend = 0.04), but was protective in men in the uppermost quintile compared to men grouped in the lower four quintiles, in post hoc analysis (p = 0.01). PC LA concentrations were inversely associated with baseline FN-BMD in women (p-trend = 0.02), and increased hip fracture risk in women and men (p-trend = 0.05), but body mass index (BMI) adjustment attenuated these associations (p-trend = 0.12 and p-trend = 0.14, respectively). A trend toward a protective association was observed between PC AA and baseline FN-BMD in men (p-trend = 0.06). Women and men with the highest PC AA concentrations had 51% lower hip fracture risk than those with the lowest (HR = 0.49, 95% CI = 0.24-1.00). Opposing effects of PC DHA on FN-BMD loss observed in women and men need further clarification. Bone loss associated with PC LA may be confounded by BMI. High PC AA concentrations may be associated with reduced hip fracture risk.

Enhanced prostaglandin F 2α formation in human pregnancy and the effect of increased oily fish intake: Results from the Salmon in Pregnancy Study

Oily fish intake during pregnancy may reduce the risk of allergic diseases in infancy possibly by shifts in the fatty acid balance and subsequent altered prostaglandin (PG) formation. This intervention is the first study to evaluate if increased oily fish intake affects in vivo PGF 2α formation during pregnancy. British pregnant women were randomised to two portions of farmed salmon weekly ( n=47), or maintenance of their normal diet low in fish ( n=41), from pregnancy week 20 until parturition. The concentrations of eicosapentaenoic and docosahexaenoic acids in plasma phosphatidylcholine (PC) were higher and the concentration of arachidonic acid in plasma PC was lower in the salmon group than the control group at weeks 34 and 38 of pregnancy. PGF 2α formation was evaluated by urinary measurement of 15-keto-dihydro-PGF 2α, a major PGF 2α metabolite, at 20, 34 and 38 weeks. In both the salmon and control groups urinary 15-keto-dihydro-PGF 2α concentrations increased significantly during pregnancy, which may be of physiological importance. Oily fish intervention altered fatty acid concentrations but did not affect urinary 15-keto-dihydro-PGF 2α concentrations in pregnant women.

Plasma Phosphatidylcholine Docosahexaenoic Acid Content and Risk of Dementia and Alzheimer Disease

Docosahexaenoic acid (DHA) is an abundant fatty acid in the brain. In the diet, DHA is found mostly in fatty fish. The content of DHA has been shown to be decreased in the brain and plasma of patients with dementia. To determine whether plasma phosphatidylcholine (PC) DHA content is associated with the risk of developing dementia. A prospective follow-up study in 899 men and women who were free of dementia at baseline, had a median age of 76.0 years, and were followed up for a mean of 9.1 years for the development of all-cause dementia and Alzheimer disease. Plasma PC fatty acid levels were measured at baseline. Cox proportional regression analysis was used to assess relative risks of all-cause dementia and Alzheimer disease according to baseline plasma levels. Ninety-nine new cases of dementia (including 71 of Alzheimer disease) occurred during the follow-up. After adjustment for age, sex, apolipoprotein E epsilon4 allele, plasma homocysteine concentration, and education level, subjects in the upper quartile of baseline plasma PC DHA levels, compared with subjects in the lower 3 quartiles, had a relative risk of 0.53 of developing all-cause dementia (95% confidence interval, 0.29-0.97; P=.04) and 0.61 of developing Alzheimer disease (95% confidence interval, 0.31-1.18; P=.14). Subjects in the upper quartile of plasma PC DHA levels had a mean DHA intake of 0.18 g/d and a mean fish intake of 3.0 servings per week (P<.001) in a subset of 488 participants. We found no other significant associations. The top quartile of plasma PC DHA level was associated with a significant 47% reduction in the risk of developing all-cause dementia in the Framingham Heart Study.

Incorporation ofcis-9,trans-11 conjugated linoleic acid and vaccenic acid (trans-11 18:1) into plasma and leucocyte lipids in healthy men consuming dairy products naturally enriched in these fatty acids

The present study investigated whether consuming dairy products naturally enriched in cis-9, trans-11 (c9,t11) conjugated linoleic acid (CLA) by modification of cattle feed increases the concentration of this isomer in plasma and cellular lipids in healthy men. The study had a double-blind cross-over design. Subjects aged 34-60 years consumed dairy products available from food retailers for 1 week and then either control (0.17 g c9,t11 CLA/d; 0.31 g trans-vaccenic acid (tVA)/d) or CLA-enriched (1.43 g c9,t11 CLA/d; 4.71 g tVA/d) dairy products for 6 weeks. After 7 weeks washout, this was repeated with the alternate products. c9,t11 CLA concentration in plasma lipids was lower after consuming the control products, which may reflect the two-fold greater c9,t11 CLA content of the commercial products. Consuming the CLA-enriched dairy products increased the c9,t11 CLA concentration in plasma phosphatidylcholine (PC) (38 %; P = 0.035), triacylglycerol (TAG) (22 %; P < 0.0001) and cholesteryl esters (205 %; P < 0.0001), and in peripheral blood mononuclear cells (PBMC) (238 %; P < 0.0001), while tVA concentration was greater in plasma PC (65 %; P = 0.035), TAG (98 %; P = 0.001) and PBMC (84 %; P = 0.004). Overall, the present study shows that consumption of naturally enriched dairy products in amounts similar to habitual intakes of these foods increased the c9,t11 CLA content of plasma and cellular lipids.

Incorporation of cis-9,trans-11 or trans-10,cis-12 conjugated linoleic acid into plasma and cellular lipids in healthy men

This study investigated the incorporation of cis-9,trans-11 conjugated linoleic acid (c9,t11 CLA) and trans-10,cis-12-CLA (t10,c12 CLA) into plasma and peripheral blood mononuclear cell (PBMC) lipids when consumed as supplements highly enriched in these isomers. Healthy men (n = 49, age 31 +/- 8 years) consumed one, two, and four capsules containing approximately 600 mg of either c9,t11 CLA or t10,c12 CLA per capsule for sequential 8 week periods followed by a 6 week washout before consuming the alternative isomer. Both isomers were incorporated in a dose-dependent manner into plasma phosphatidylcholine (PC) (c9,t11 CLA r = 0.779, t10,c12 CLA r = 0.738; P < 0.0001) and cholesteryl ester (CE) (c9,t11 CLA r = 0.706, t10,c12 CLA r = 0.788; P < 0.0001). Only t10,c12 CLA was enriched in plasma nonesterified fatty acids. Both c9,t11 CLA and t10,c12 CLA were incorporated linearly into PBMC total lipids (r = 0.285 and r = 0.273, respectively; P < 0.0005). The highest concentrations of c9,t11 CLA and t10,c12 CLA in PBMC lipids were 3- to 4-fold lower than those in plasma PC and CE. These data suggest that the level of intake is a major determinant of plasma and PBMC CLA content, although PBMCs appear to incorporate both CLA isomers less readily.