Dietary Fatty Acids Differentially Regulate Secretion of Adiponectin and Interleukin‐6 in Primary Canine Adipose Tissue Culture

The aim of this study was to determine the effect of n3 polyunsaturated fatty acids (PUFA) on canine adipose tissue secretion of adiponectin, interleukin‐6 (IL6), and tumor necrosis factor‐α (TNFα). Subcutaneous and omental visceral adipose tissue samples were collected from 16 healthy intact female dogs. Concentrations of adiponectin were measured in mature adipocyte cultures, and concentrations of IL6 and TNFα were measured in undifferentiated stromovascular cell (SVC) cultures following treatment with eicosapentaenic acid (EPA, 20:5n‐3), arachidonic acid (ARA, 20:4n‐6), or palmitic acid (PAM, 16:0) at 25, 50, or 100 μM. Secretion of adiponectin from mature adipocytes was higher (p < 0.001) following EPA treatment at 50 μM compared to control in subcutaneous tissue, and higher following EPA treatment compared to PAM treatment at 25 μM in both subcutaneous (p < 0.001) and visceral tissues (p = 0.010). Secretion of IL6 from SVC derived from subcutaneous tissue was lower following EPA treatment and higher following PAM treatment compared to control both at 50 μM (p = 0.001 and p = 0.041, respectively) and 100 μM (p = 0.013 and p < 0.001, respectively). These findings of stimulation of adiponectin secretion and inhibition of IL6 secretion by EPA, and stimulation of IL6 secretion by PAM, are consistent with findings of increased circulating concentrations of adiponectin and decreased circulating concentration of IL6 in dogs supplemented with dietary fish oil, and show that the effect of fish oil on circulating concentrations of adiponectin and IL6 is, at least partially, the result of local effects of EPA and PAM on adipose tissue.     

Evaluation of a Rapid Assessment Questionnaire Using a Biomarker for Dietary Intake of n-3 Fatty Acids

While there is considerable evidence supporting health benefits of consuming diets high in omega-3 (n-3) fatty acids, there is no quick and effective tool to measure n-3 intake. The objective of this study was to evaluate the accuracy of a rapid assessment questionnaire (the Omega-3 Checklist) used to quantify intake of n-3 fatty acids. This was done by comparing n-3 intakes to blood biomarkers of n-3 exposure in a population of healthy men and women. In addition, a separate analysis was run including covariates age, sex, and weight, which have been shown to affect n-3 biomarker levels. Reported intake of eicosapentaenoic acid (EPA), docoshexaenoic acid (DHA), and EPA + DHA was correlated with erythrocyte EPA (Spearman’s rank correlation r_s = 0.51, p < 0.001), DHA (r_s = 0.54, p < 0.001), and the Omega-3 Index (r_s = 0.57, p < 0.001). These associations remained significant when controlling for age, sex, and weight. Therefore, the Omega-3 Checklist can be a useful, rapid assessment tool to estimate individuals’ EPA and DHA intake.     

n-3 Docosapentaenoic Acid Intake and Relationship with Plasma Long-Chain n-3 Fatty Acid Concentrations in the United States: NHANES 2003–2014

The long-chain n-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), play a crucial role in health, but previous National Health and Nutrition Examination Survey (NHANES) analyses have shown that EPA and DHA intake in the United States is far below recommendations (~250–500 mg/day EPA + DHA). Less is known about docosapentaenoic acid (DPA), the metabolic intermediate of EPA and DHA; however, evidence suggests DPA may be an important contributor to long-chain n-3 fatty acid intake and impart unique benefits. We used NHANES 2003–2014 data (n = 45,347) to assess DPA intake and plasma concentrations, as well as the relationship between intake and plasma concentrations of EPA, DPA, and DHA. Mean DPA intake was 22.3 ± 0.8 mg/day from 2013 to 2014, and increased significantly over time (p < 0.001), with the lowest values from 2003 to 2004 (16.2 ± 1.2 mg/day). DPA intake was higher in adults (20–55 years) and seniors (55+ years) compared to younger individuals. In regression analyses, DPA intake was a significant predictor of plasma EPA (β = 138.5; p < 0.001) and DHA (β = 318.9; p < 0.001). Plasma DPA was predicted by EPA and DHA intake (β = 13.15; p = 0.001 and β = 7.4; p = 0.002), but not dietary DPA (p = 0.3). This indicates that DPA intake is not a good marker of plasma DPA status (or vice versa), and further research is needed to understand the factors that affect the interconversion of EPA and DPA. These findings have implications for future long-chain n-3 fatty acids dietary recommendations.     

Differential Response to an Algae Supplement High in DHA Mediated by Maternal Periconceptional Diet: Intergenerational Effects of n-6 Fatty Acids

Algae high in docosahexaenoic acid (DHA) may provide a source of long‐chain omega‐3 polyunsaturated fatty acids (LCn‐3PUFA) for inclusion in the diet of lambs to improve the LCn‐3PUFA status of meat. The effect of background LCn‐3PUFA status on the metabolism of high DHA algae is, however, unknown. The aim of the current study was to determine whether the response to a high in DHA algae supplement fed to lambs for six weeks prior to slaughter was mediated by a maternal periconceptional diet. Forty Poll Dorset × Border Leicester × Merino weaner lambs were allocated to receive either a ration based on oat grain, lupin grain, and chopped lucerne (control) or the control ration with DHA‐Gold? algae included at 1.92 % DM (Algae) based on whether the dams of lambs had previously been fed a diet high in n‐3 or n‐6 around conception. LCn‐3PUFA concentration was determined in plasma and red blood cells (RBC) prior to and following feeding. The concentrations of EPA and DHA in the plasma and RBC of lambs receiving the control ration were significantly (p < 0.001) lower when lambs received the ration for 14 days compared with pre‐feeding concentrations. The concentrations of EPA and DHA were also significantly (p < 0.001) higher when lambs consumed the Algae ration compared with the control ration for 42 days. The increase in EPA and DHA was, however, significantly (p < 0.05) lower if lamb dams had previously been fed a diet high in n‐6 at conception. Assessing the previous nutrition and n‐3 status of lambs may allow producers to more accurately predict the likely response to supplements high in LCn‐3PUFA, particularly, DHA.     

Docosahexaenoic Acid and Eicosapentaenoic Acid Did not Alter <Emphasis Type="Italic">trans</Emphasis>-10,<Emphasis Type="Italic">cis</Emphasis>-12 Conjugated Linoleic Acid Incorporation into Mice Brain and Eye Lipids

trans 10,cis 12‐CLA has been reported to alter fatty acid composition in several non‐neurological tissues, but its effects are less known in neurological tissues. Therefore, the purpose of this study was to determine if CLA supplementation would alter brain and eye fatty acid composition and if those changes could be prevented by concomitant supplementation with docosahexaenoic acid (DHA; 22:6n3) or eicosapentaenoic acid (EPA; 20:5n3). Eight‐week‐old, pathogen‐free C57BL/6N female mice (n = 6/group) were fed either the control diet or diets containing 0.5% (w/w) t10,c12‐CLA in the presence or absence of either 1.5% DHA or 1.5% EPA for 8 weeks. CLA concentration was significantly (P < 0.05) greater in the eye but not in the brain lipids of the CLA group when compared with the control group. The sums of saturated, monounsaturated, polyunsaturated fatty acids, and n3:n6 ratio did not differ between these two groups for both tissues. The n3:n6 ratio and concentrations of 20:5n3 and 22:5n3 were significantly greater, and those of 20:4n6, 22:4n6, and 22:5n6 were lesser in the CLA + DHA and CLA + EPA groups than in the control and CLA groups for either tissue. DHA concentration was higher in the CLA + DHA group only but not in the CLA + EPA group when compared with the CLA group for both tissues. The dietary fatty acids generally induced similar changes in brain and eye fatty acid concentration and at the concentrations used both DHA and EPA fed individually with CLA were more potent than CLA alone in altering the tissue fatty acid concentration.     

Fatty Acid and Lipid Profiles with Emphasis on n-3 Fatty Acids and Phospholipids from Ciona intestinalis

In order to establish Ciona intestinalis as a new bioresource for n‐3 fatty acids‐rich marine lipids, the animal was fractionated into tunic and inner body tissues prior to lipid extraction. The lipids obtained were further classified into neutral lipids (NL), glycolipids (GL) and phospholipids (PL) followed by qualitative and quantitative analysis using GC‐FID, GC–MS, ¹H NMR, 2D NMR, MALDI‐TOF‐MS and LC–ESI–MS methods. It was found that the tunic and inner body tissues contained 3.42–4.08 % and 15.9–23.4 % of lipids respectively. PL was the dominant lipid class (42–60 %) irrespective of the anatomic fractions. From all lipid fractions and classes, the major fatty acids were 16:0, 18:1n‐9, C20:1n‐9, C20:5n‐3 (EPA) and C22:6n‐3 (DHA). The highest amounts of long chain n‐3 fatty acids, mainly EPA and DHA, were located in PL from both body fractions. Cholestanol and cholesterol were the dominant sterols together with noticeable amounts of stellasterol, 22 (Z)‐dehydrocholesterol and lathosterol. Several other identified and two yet unidentified sterols were observed for the first time from C. intestinalis. Different molecular species of phosphatidylcholine (34 species), sphingomyelin (2 species), phosphatidylethanolamine (2 species), phosphatidylserine (10 species), phosphatidylglycerol (9 species), ceramide (38 species) and lysophospholipid (5 species) were identified, representing the most systematic PL profiling knowledge so far for the animal. It could be concluded that C. intestinalis lipids should be a good alternative for fish oil with high contents of n‐3 fatty acids. The lipids would be more bioavailable due to the presence of the fatty acids being mainly in the form of PL.     

Fish Oil Decreases C-Reactive Protein/Albumin Ratio Improving Nutritional Prognosis and Plasma Fatty Acid Profile in Colorectal Cancer Patients

Previous studies have shown that n‐3 polyunsaturated fatty acids n‐3 (n‐3 PUFA) have several anticancer effects, especially attributed to their ability to modulate a variety of genomic and immune responses. In this context, this randomized, prospective, controlled clinical trial was conducted in order to check whether supplementation of 2 g/day of fish oil for 9 weeks alters the production of inflammatory markers, the plasma fatty acid profile and the nutritional status in patients with colorectal cancer (CRC). Eleven adults with CRC in chemotherapy were randomized into two groups: (a) supplemented (SG) daily with 2 g/day of encapsulated fish oil [providing 600 mg/day of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA)] for 9 weeks (n = 6), and (b) control (CG) (n = 5). All outcomes were evaluated on the day before the first chemotherapy session and 9 weeks later. Plasma TNF‐α, IL‐1β, IL‐10 and IL‐17A, the pro/anti‐inflammatory balance (ratio TNF‐α/IL‐10 and IL‐1β/IL10) and serum albumin, showed no significant changes between times and study groups (p > 0.05). C‐reactive protein (CRP) and the CRP/albumin ratio showed opposite behavior in groups, significantly reducing their values in SG (p < 0.05). Plasma proportions of EPA and DHA increased 1.8 and 1.4 times, respectively, while the ARA reduced approximately 0.6 times with the supplementation (9 weeks vs baseline, p < 0.05). Patients from SG gained 1.2 kg (median) while the CG lost ?0.5 kg (median) during the 9 weeks of chemotherapy (p = 0.72). These results demonstrate that 2 g/day of fish oil for 9 weeks of chemotherapy improves CRP values, CRP/albumin status, plasma fatty acid profile and potentially prevents weight loss during treatment.     

Lipase selectivity toward fatty acids commonly found in fish oil

The main objective of this study was to compare the fatty acid selectivity of numerous commercially available lipases toward the most ubiquitous fatty acids present in fish oils in form of their corresponding ethyl esters. Special interest was taken in their ability to separate the n‐3 long‐chain polyunsaturated fatty acids (PUFA), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), from the more saturated fatty acids as well as exploiting the putative discrimination between these highly valuable n‐3 PUFA. Hydrolysis of sardine oil ethyl esters in a Tris buffer solution by 12 microbial lipases is described. The results reveal that all of the lipases strongly discriminate against the n‐3 PUFA and prefer the more saturated fatty acids as substrates. Most of the lipases discriminate between EPA and DHA in favor of EPA, however, 2 bacterial lipases from Pseudomonas were observed to prefer DHA to EPA. Digestive lipolytic enzymes isolated from salmon and rainbow trout intestines displayed reversed fatty acid selectivity when their fish oil triacylglycerol hydrolysis was studied. Thus, the n‐3 PUFA including EPA and DHA were observed to be hydrolyzed at a considerably higher rate than the more saturated fatty acids.     

n‐3 PUFA Esterified to Glycerol or as Ethyl Esters Reduce Non‐Fasting Plasma Triacylglycerol in Subjects with Hypertriglyceridemia: A Randomized Trial

To date, treatment of hypertriglyceridemia with long‐chain n‐3 polyunsaturated fatty acids (n‐3 PUFA) has been investigated solely in fasting and postprandial subjects. However, non‐fasting triacylglycerols are more strongly associated with risk of cardiovascular disease. The objective of this study was to investigate the effect of long‐chain n‐3 PUFA on non‐fasting triacylglycerol levels and to compare the effects of n‐3 PUFA formulated as acylglycerol (AG‐PUFA) or ethyl esters (EE‐PUFA). The study was a double‐blinded randomized placebo‐controlled interventional trial, and included 120 subjects with non‐fasting plasma triacylglycerol levels of 1.7–5.65 mmol/L (150–500 mg/dL). The participants received approximately 3 g/day of AG‐PUFA, EE‐PUFA, or placebo for a period of eight weeks. The levels of non‐fasting plasma triacylglycerols decreased 28 % in the AG‐PUFA group and 22 % in the EE‐PUFA group (P < 0.001 vs. placebo), with no significant difference between the two groups. The triacylglycerol lowering effect was evident after four weeks, and was inversely correlated with the omega‐3 index (EPA + DHA content in erythrocyte membranes). The omega‐3 index increased 63.2 % in the AG‐PUFA group and 58.5 % in the EE‐PUFA group (P < 0.001). Overall, the heart rate in the AG‐PUFA group decreased by three beats per minute (P = 0.045). High‐density lipoprotein (HDL) cholesterol increased in the AG‐PUFA group (P < 0.001). Neither total nor non‐HDL cholesterol changed in any group. Lipoprotein‐associated phospholipase A2 (LpPLA2) decreased in the EE‐PUFA group (P = 0.001). No serious adverse events were observed. Supplementation with long‐chain n‐3 PUFA lowered non‐fasting triacylglycerol levels, suggestive of a reduction in cardiovascular risk. Regardless of the different effects on heart rate, HDL, and LpPLA2 that were observed, compared to placebo, AG‐PUFA, and EE‐PUFA are equally effective in reducing non‐fasting triacylglycerol levels.     

Forms of n‐3 (ALA,C18:3n‐3 or DHA,C22:6n‐3) Fatty Acids Affect Carcass Yield,Blood Lipids,Muscle n‐3 Fatty Acids and Liver Gene Expression in Lambs

The effects of supplementing diets with n‐3 alpha‐linolenic acid (ALA) and docosahexaenoic acid (DHA) on plasma metabolites, carcass yield, muscle n‐3 fatty acids and liver messenger RNA (mRNA) in lambs were investigated. Lambs (n = 120) were stratified to 12 groups based on body weight (35 ± 3.1 kg), and within groups randomly allocated to four dietary treatments: basal diet (BAS), BAS with 10.7 % flaxseed supplement (Flax), BAS with 1.8 % algae supplement (DHA), BAS with Flax and DHA (FlaxDHA). Lambs were fed for 56 days. Blood samples were collected on day 0 and day 56, and plasma analysed for insulin and lipids. Lambs were slaughtered, and carcass traits measured. At 30 min and 24 h, liver and muscle samples, respectively, were collected for determination of mRNA (FADS1, FADS2, CPT1A, ACOX1) and fatty acid composition. Lambs fed Flax had higher plasma triacylglycerol, body weight, body fat and carcass yield compared with the BAS group (P < 0.001). DHA supplementation increased carcass yield and muscle DHA while lowering plasma insulin compared with the BAS diet (P < 0.01). Flax treatment increased (P < 0.001) muscle ALA concentration, while DHA treatment increased (P < 0.001) muscle DHA concentration. Liver mRNA FADS2 was higher and CPT1A lower in the DHA group (P < 0.05). The FlaxDHA diet had additive effects, including higher FADS1 and ACOX1 mRNA than for the Flax or DHA diet. In summary, supplementation with ALA or DHA modulated plasma metabolites, muscle DHA, body fat and liver gene expression differently.     

EPA,DHA, and Lipoic Acid Differentially Modulate the n-3 Fatty Acid Biosynthetic Pathway in Atlantic Salmon Hepatocytes

The aim of the present study was to investigate how EPA, DHA, and lipoic acid (LA) influence the different metabolic steps in the n‐3 fatty acid (FA) biosynthetic pathway in hepatocytes from Atlantic salmon fed four dietary levels (0, 0.5, 1.0 and 2.0%) of EPA, DHA or a 1:1 mixture of these FA. The hepatocytes were incubated with [1‐¹⁴C] 18:3n‐3 in the presence or absence of LA (0.2 mM). Increased endogenous levels of EPA and/or DHA and LA exposure both led to similar responses in cells with reduced desaturation and elongation of [1‐¹⁴C] 18:3n‐3 to 18:4n‐3, 20:4n‐3, and EPA, in agreement with reduced expression of the Δ6 desaturase gene involved in the first step of conversion. DHA production, on the other hand, was maintained even in groups with high endogenous levels of DHA, possibly due to a more complex regulation of this last step in the n‐3 metabolic pathway. Inhibition of the Δ6 desaturase pathway led to increased direct elongation to 20:3n‐3 by both DHA and LA. Possibly the route by 20:3n‐3 and then Δ8 desaturation to 20:4n‐3, bypassing the first Δ6 desaturase step, can partly explain the maintained or even increased levels of DHA production. LA increased DHA production in the phospholipid fraction of hepatocytes isolated from fish fed 0 and 0.5% EPA and/or DHA, indicating that LA has the potential to further increase the production of this health‐beneficial FA in fish fed diets with low levels of EPA and/or DHA.     

Oxidative stability and acceptability of camelina oil blended with selected fish oils

The effects of blending camelina oil with a number of fish oils on oxidative stability and fishy odour were evaluated. Camelina oil was found to be more stable than tuna oil, ‘omega‐3’ fish oil and salmon oil as indicated by predominantly lower ρ‐anisidine (AV), thiobarbituric acid reactive substances (TBARS) and conjugated triene levels (CT) during storage at 60 °C for 20 days (p < 0.05). Peroxide values (PV) were similar for all oils until Day 13 when values for camelina oil were higher. Values for blends of the fish oils (50, 25, 15, 5%) with camelina oil were generally between those of their respective bulk oils indicating a dilution effect. Camelina oil had a similar odour score (p < 0.05) to sunflower oil (9.2 and 9.6, respectively) indicating, as expected, an absence of fishy odours. In comparison, the fish oils had lower scores of 6.1 to 6.6 (p < 0.05) indicating mild to moderate fishy odours. Odour scores were improved at the 25% fish oil levels (p < 0.05) and were not different to camelina oil at the 15 or 5% levels (p < 0.05). Practical applications: Camelina oil is a potentially important functional food ingredient providing beneficial n‐3 PUFA. Oil extracted from Camelina sativa seeds contains greater than 50% polyunsaturated fatty acids of which 35‐40% is α‐linolenic acid (C18:3ω3, ALA), an essential omega‐3 fatty acid 1 . While EPA and DHA from fish oils are more potent nutritionally, they are less stable than ALA. This work evaluated innovative blends of fish oil with camelina oil for stability and acceptability. The results demonstrate that there is potential for use of blends of camelina oil with fish oils in food products, as the results show some benefits in terms of reduction of fishy odours. Such information could be valuable in relation to formulation of food products containing high levels of n‐3 PUFA from both plant and fish sources.     

Fatty Acid Composition of Tropical Fish Depends on Reservoir Trophic Status and Fish Feeding Habit

Eutrophication results in a deficiency of n‐3 LC‐PUFA (long‐chain polyunsaturated fatty acids) in aquatic food chains, affecting fish nutrition and physiology. The trophic transfer of FA (fatty acids) to fish species of different feeding habits was investigated in two reservoirs in southeast Brazil—the mesotrophic Ponte Nova Reservoir (PN) and the hypereutrophic Billings Reservoir (Bil). Total FA profile of stomach contents and adipose tissue, triacylglycerols (TAG), and phospholipids (PL) from liver and muscle of the omnivorous Astyanax fasciatus and the carnivorous Hoplias malabaricus were analyzed by gas chromatography. A prevalence of n‐6PUFA, as 18:2n‐6 (linoleic acid) and 20:4n‐6 (arachidonic acid, ARA) was observed in the stomach contents and in the tissues of A. fasciatus from the PN reservoir. In contrast, n‐3 LC‐PUFA, as 20:5n‐3 (eicosapentaenoic acid, EPA) was accumulated in fish tissues from Bil, resulting in higher n3/n6 and EPA/ARA ratios, compared to fish from PN. This differential FA accumulation was also observed for H. malabaricus, but differences were slightly minor, and no changes were observed in the EPA/ARA ratios between fish from both reservoirs. Regardless reservoir, FA profiles of TAG resembled that of their diet, whereas FA profiles of PL were more conservative and mainly comprised by LC‐PUFA. We conclude that reservoir trophic status affected the FA composition of food resources available to these fish species, resulting in differential allocation of n‐3 and n‐6 FA. As expected, FA profile of the investigated fish species also reflected their feeding habit and physiological demands.     

The effects of season on fat and fatty acids contents of shrimp and prawn species

The effects of seasons on the lipid content and fatty acid compositions of five different shrimp and prawn species (green tiger prawn – Penaeus semisulcatus, kuruma prawn – Marsupenaeus japonicus, caramote prawn – Melicertus kerathurus, deepwater pink shrimp – Parapenaeus longirostris, speckled shrimp – Metapenaeus monoceros) were evaluated. Results showed that lipid content ranged from 0.89 to 1.55% in muscle, showing that all species were considered as lean. There were significant differences (p<0.05) in the levels of saturated fatty acids (SFA), monounsaturated fatty acids and polyunsaturated fatty acids (PUFA) in terms of season and species. They were rich in n‐3 fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The highest proportions of EPA were obtained from kuruma prawn (180.9 mg/100 g) in spring and deepwater pink shrimp (173.2 mg/100 g) and caramote prawn (146.3 mg/100 g) in summer. Kuruma prawn had the highest DHA in spring (140.8 mg/100 g) followed by deepwater pink shrimp (132.2 mg/100 g) and caramote prawn (129.6 mg/100 g) in summer. The results also showed that the seasons affected lipid content and the fatty acid composition of shrimp and prawn species. Practical Application: The beneficial effect of seafood consumption on human health has been related to the high content of n‐3 fatty acids, especially EPA (20:5n‐3) and DHA (22:6n‐3). The ratios of n‐6/n‐3, PUFA/SFA and EPA + DHA are considered as useful criteria for comparing relative nutritional and oxidation values of marine oils. In the current study, the influence of seasonality on the lipid content and the fatty acid compositions of shrimp and prawn were investigated in order to find the best source of n‐3 fatty acids during the year.     

Thermal degradation of long‐chain polyunsaturated fatty acids during deodorization of fish oil

Long‐chain polyunsaturated fatty acids (LC‐PUFA) of the n‐3 series, particularly eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid, have specific activities especially in the functionality of the central nervous system. Due to the occurrence of numerous methylene‐interrupted ethylenic double bonds, these fatty acids are very sensitive to air (oxygen) and temperature. Non‐volatile degradation products, which include polymers, cyclic fatty acid monomers (CFAM) and geometrical isomers of EPA and DHA, were evaluated in fish oil samples obtained by deodorization under vacuum of semi‐refined fish oil at 180, 220 and 250 °C. Polymers are the major degradation products generated at high deodorization temperatures, with 19.5% oligomers being formed in oil deodorized at 250 °C. A significant amount of CFAM was produced during deodorization at temperatures above or equal to 220 °C. In fact, 23.9 and 66.3 mg/g of C20 and C22 CFAM were found in samples deodorized at 220 and 250 °C, respectively. Only minor changes were observed in the EPA and DHA trans isomer content and composition after deodorization at 180 °C. At this temperature, the formation of polar compounds and CFAM was also low. However, the oil deodorized at 220 and 250 °C contained 4.2% and 7.6% geometrical isomers, respectively. Even after a deodorization at 250 °C, the majority of geometrical isomers were mono‐ and di‐trans. These results indicate that deodorization of fish oils should be conducted at a maximal temperature of 180 °C. This temperature seems to be lower than the activation energy required for polymerization (intra and inter) and geometrical isomerization.     

Dietary Unsaturated Fatty Acids Modulate Maternal Dyslipidemia‐Induced DNA Methylation and Histone Acetylation in Placenta and Fetal Liver in Rats

The present study assessed the role of dietary unsaturated fatty acids in maternal dyslipidemia‐induced DNA methylation and histone acetylation in placenta and fetal liver and accumulation of lipids in the fetal liver. Weanling female Wistar rats were fed control and experimental diets for 2 months, mated, and continued on their diets during pregnancy. At gestation days of 18–20, rats were euthanized to isolate placenta and fetal liver. DNA methylation, DNA methyl transferase‐1 (DNMT1) activity, acetylation of histones (H2A and H2B), and histone acyl transferase (HAT) activity were evaluated in placenta and fetal liver. Fetal liver lipid accumulation and activation of peroxisome proliferator‐activated receptor‐α (PPAR‐α) were assessed. Maternal dyslipidemia caused significant epigenetic changes in placenta and fetal liver. In the placenta, (1) global DNA methylation increased by 37% and DNMT1 activity by 86%, (2) acetylated H2A and H2B levels decreased by 46% and 24% respectively, and (3) HAT activity decreased by 39%. In fetal liver, (1) global DNA methylation increased by 52% and DNMT1 activity by 78%, (2) acetylated H2A and H2B levels decreased by 28% and 26% respectively, and (3) HAT activity decreased by 37%. Maternal dyslipidemia caused a 4.75‐fold increase in fetal liver triacylglycerol accumulation with a 78% decrease in DNA‐binding ability of PPAR‐α. Incorporation of dietary unsaturated fatty acids in the maternal high‐fat diet significantly (p < 0.05) modulated dyslipidemia‐induced effects in placenta and fetal liver. Eicosapentaenoic acid (EPA, 20:5n‐3) + docosahexaenoic acid (DHA, 22:6n‐3) exhibited a profound effect followed by alpha‐linolenic acid (ALA, 18:3n‐3) than linoleic acid (LNA, 18:2n‐6) in modulating the epigenetic parameters in placenta and fetal liver.     

Higher Increase in Plasma DHA in Females Compared to Males Following EPA Supplementation May Be Influenced by a Polymorphism in ELOVL2: An Exploratory Study

Young adult females have higher blood docosahexaenoic acid (DHA), 22:6n-3 levels than males, and this is believed to be due to higher DHA synthesis rates, although DHA may also accumulate due to a longer half-life or a combination of both. However, sex differences in blood fatty acid responses to eicosapentaenoic acid (EPA), 20:5n-3 or DHA supplementation have not been fully investigated. In this exploratory analysis, females and males (n = 14–15 per group) were supplemented with 3 g/day EPA, 3 g/day DHA, or olive oil control for 12 weeks. Plasma was analyzed for sex effects at baseline and changes following 12 weeks' supplementation for fatty acid levels and carbon-13 signature (δ¹³C). Following EPA supplementation, the increase in plasma DHA in females (+23.8 ± 11.8, nmol/mL ± SEM) was higher than males (−13.8 ± 9.2, p < 0.01). The increase in plasma δ¹³C-DHA of females (+2.79 ± 0.31, milliUrey (mUr ± SEM) compared with males (+1.88 ± 0.44) did not reach statistical significance (p = 0.10). The sex effect appears driven largely by increased plasma DHA in the AA genotype of females (+58.8 ± 11.5, nmol/mL ± SEM, n = 5) compared to GA + GG in females (+4.34 ± 13.5, n = 9) and AA in males (−29.1 ± 17.2, n = 6) for rs953413 in the ELOVL2 gene (p < 0.001). In conclusion, EPA supplementation increases plasma DHA levels in females compared to males, which may be dependent on the AA genotype for rs953413 in ELOVL2.     

Alpha‐Linolenic Acid,but Not Palmitic Acid,Negatively Impacts Survival,Asexual Reproductive Rate,and Clonal Offspring Size in Hydra oligactis

Hydra, as sit‐and‐wait predators with limited food selectivity, could serve as model organisms for the analysis of the effect of a particular dietary component on growth and reproduction. We investigated the effect of food quality and of diets enriched with palmitic (PAM) or α‐linolenic acid (ALA) on the life history traits of two hydra species: Hydra oligactis and Hydra vulgaris. We tested the hypothesis that a diet enriched with polyunsaturated fatty acids (PUFA) can stimulate growth and reproduction in simple metazoans with a sit‐and‐wait type of predatory strategy. Our results revealed that a diet based on Artemia nauplii, which are not a natural food for freshwater hydra, stimulated growth, asexual reproduction, and survival in hydra. Artemia nauplii were characterized by the highest lipid content of all used food sources. The analysis of the fatty acid content of hydra indicated the domination the n‐6 fatty acids over n‐3 (eicosapentaenoic acid [EPA], docosahexaenoic acid [DHA], and ALA). Arachidonic acid appeared to be the dominant PUFA in Hydra, irrespective of diet supplementation with palmitic acid or ALA. The dietary supplementation of ALA negatively affected the survival, asexual reproductive rate, and size of clonal offspring of H. oligactis and had no effect on the life history traits of H. vulgaris. Our results also suggest that the hydras are not able to efficiently convert ALA into other essential fatty acids, such as EPA and DHA. To our knowledge, this is the first report about the adverse effects of n‐3 fatty acid supplementation in primitive metazoans such as hydra.     

Marine phospholipids as dietary carriers of long‐chain polyunsaturated fatty acids

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are polyunsaturated fatty acids (PUFA) of the n‐3 series. Fish oil is a classical source of n‐3 PUFA, where they occur in the form of triacylglycerols (TAG). However, new sources of n‐3 PUFA esterified in phospholipids (PL) are emerging. We prepared liposomes from a natural marine lipid extract and examined their behaviour under conditions mimicking that of the gastrointestinal tract. This physicochemical approach proved that liposomes could be used as an effective oral PUFA delivery system. In vivo studies in rats were performed to examine the metabolic fate of EPA (20:5 n‐3) and DHA (22:6 n‐3) delivered either in PL from liposomes or in TAG from oil. Liposome ingestion increased PUFA bioavailability in lymph compared with fish oil. The proportion of n‐3 PUFA esterified in the sn‐2 position of chylomicron TAG depended on the dietary lipid source. Complex time‐course profiles were observed for plasma lipids with liposome supplementation over a 2‐week period, suggesting time‐dependent regulations. Taken together, the type of PUFA, EPA or DHA, as well as its intramolecular distribution in chylomicron TAG seemed to influence the metabolic fate of the fatty acids and their physiological activities.     

Improvement of Major Depression is Associated with Increased Erythrocyte DHA

The aim of this study was to determine if changes in omega‐3 polyunsaturated fatty acid status following tuna oil supplementation correlated with changes in scores of depression. A total of 95 volunteers receiving treatment for major depression were randomised to consume 8 × 1 g capsules per day of HiDHA (2 g DHA, 0.6 g EPA and 10 mg Vitamin E) or olive oil (placebo) for 16 weeks, whilst undergoing weekly counseling sessions by trained clinical psychologists using a standard empirically validated psychotherapy. Depression status was assessed using the 17 item Hamilton rating scale for depression and the Beck Depression Inventory by a psychodiagnostician who was blind to the treatment. Blood was taken at baseline and 16 weeks (n = 48) for measurement of erythrocyte fatty acids. With HiDHA supplementation, erythrocyte DHA content rose from 4.1 ± 0.2 to 7.9 ± 0.4 % (mean ± SEM, p < 0.001) of total fatty acids but did not change (4.0 ± 0.2 to 4.1 ± 0.2 %) in the olive oil group. The mean changes in scores of depression did not differ significantly between the two groups (?12.2 ± 2.1 for tuna oil and ?14.4 ± 2.3 for olive oil). However, analysis of covariance showed that in the fish oil group there was a significant correlation (r = ?0.51) between the change in erythrocyte DHA and the change in scores of depression (p < 0.05). Further study of the relationship between DHA and depression is warranted.