Omega-3 Long-chain Polyunsaturated Fatty Acids Research Articles

Fortification of diets with omega-3 long-chain polyunsaturated fatty acids enhances feedlot performance, intramuscular fat content, fat melting point, and carcass characteristics of Tattykeel Australian White MARGRA lambs.

Meat eating quality indices such as intramuscular fat content (IMF) and fat melting point (FMP) of the Longissimus thoracis et lumborum muscle and the feedlot performance, carcass traits, and commercial wholesale cuts of lot-fed Tattykeel Australian White (TAW) MARGRA lambs as a result of dietary fortification of the diet with omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) were evaluated. A total of 75 TAW MARGRA lambs at 6 months of age with an average liveweight of 30 ± 1.2 kg were used. The lambs were randomly allocated to the following three dietary treatments of 25 lambs each in a 47-day feeding trial using a completely randomized experimental design: (1) control diet of hay plus pellets without omega-3 oil, (2) hay plus commercial whole grain pellets (MSM) without omega-3 oil, and (3) hay plus pellets fortified with omega-3 oil. It was hypothesized that dietary supplementation with omega-3 fortified pellets will improve feedlot performance, meat-eating quality indices of IMF, FMP, and carcass characteristics. Lot-fed lambs on the MSM whole grain had the highest feed intake of 1.69 kg/day, followed by the control at 1.57 kg/day and the lowest in the omega-3 diet at 1.01 kg/day (p = 0.0001). However, the omega-3 diet had the highest average daily gain of 230 g/head/day (p = 0.0001), indicating the greatest feed efficiency since it had the best growth response with minimal feed intake. Post-slaughter evaluation of the Longissimus thoracis et lumborum muscle revealed significant treatment variations in IMF (p = 0.0001), FMP (p = 0.0001), pH (p = 0.0380), and wholesale French rack primal cut (p = 0.0001). Strong correlations (p < 0.05) between liveweight, temperature, pH, FMP, and IMF were observed. Similarly, significant correlations between carcass characteristics of total saleable meat yield, lean trim, fat trims, bones, and leg shank were evident (p < 0.05). However, there were no treatment differences in the final liveweight, GR fat depth, hot standard carcass weight, or dressing percentage. The findings indicate that feedlot performance, meat-eating quality traits such as IMF and FMP, and commercial wholesale French rack cuts can be further improved during feedlot finishing of TAW MARGRA lambs through dietary supplementation with omega-3 oils, and hence the tested hypothesis of improved meat quality attributes is partially confirmed.

P3 - Omega-3 to Reduce the Incidence of Preterm Birth – from bench to bedside

Globally, preterm birth is the leading cause of death in children under 5 years. Around two thirds of preterm births occur without known biological cause, therefore prevention strategies are critical. Increased intake of omega-3 long chain polyunsaturated fatty acids (LCPUFAs) during pregnancy has been linked to increased length of gestation and reduction of preterm birth. We aimed to determine the effect of supplementing the diets of pregnant women with omega-3 LCPUFA on the incidence of early preterm birth (<34 weeks’ gestation). A national, multicentre, double blind, parallel group, randomised controlled trial. 5544 pregnant women were randomised to daily capsules containing 900 mg omega-3 (800 mg docosahexaenoic acid and 100 mg eicosapentaenoic acid) or vegetable oil (control) from <20 weeks until 34 weeks’ gestation. Our primary outcome was the incidence of early preterm birth. Overall, there was no significant difference in the incidence of early preterm birth in the omega-3 group compared to control. However, exploratory analyses (n=5070 singleton pregnancies) found the risk of early preterm birth in women with low omega-3 status at enrolment was significantly reduced by 77% with omega-3 supplementation (RR = 0.23, 95% CI 0.07-0.79). In contrast, women with replete omega-3 status were already at lower risk of early birth and supplementation increased their risk of early preterm birth (RR = 2.27, 95% CI 1.13-4.58). Women with low omega-3 status benefit most from omega-3 supplementation to reduce their risk of early preterm birth. The 2018 Cochrane review including >70 trials supports our findings reporting a 42% reduction in early preterm birth. The 2021 Australian Pregnancy Care Guidelines now contain a new evidence-based recommendation to advise omega-3 supplementation to reduce the risk of prematurity for women who are low in omega-3. A state-wide implementation and evaluation of the guideline is underway in South Australia.

Perspective: Role of Micronutrients and Omega-3 Long-Chain Polyunsaturated Fatty Acids for Immune Outcomes of Relevance to Infections in Older Adults—A Narrative Review and Call for Action

ABSTRACTThe immune system is weakened by advancing age, often referred to as immunosenescence, increasing the vulnerability to, and frequently the severity of, infectious diseases in older people. This has become very apparent in the current coronavirus disease 2019 (COVID-19) pandemic for which older people are at higher risk of severe outcomes, even those who are fully vaccinated. Aging affects both the innate and adaptive immune systems and is characterized by an imbalanced inflammatory response. Increasing evidence shows that optimal status of nutrients such as vitamins C, D, and E and selenium and zinc as well as the omega-3 (n–3) fatty acids DHA and EPA can help compensate for these age-related changes. While inadequate intakes of these nutrients are widespread in the general population, this is often more pronounced in older people. Maintaining adequate intakes is a challenge for them due to a range of factors such as physical, physiological, and cognitive changes; altered absorption; and the presence of noncommunicable diseases. While nutritional requirements are ideally covered by a balanced diet, this can be difficult to achieve, particularly for older people. Fortified foods and nutritional complements are effective in achieving adequate micronutrient intakes and should be considered as a safe and cost-effective means for older people to improve their nutritional status and hence support their defense against infections. Complementing the diet with a combination of micronutrients, particularly those playing a key role in the immune system such as vitamins C, D, and E and selenium and zinc as well as DHA and EPA, is recommended for older people. Optimal nutrition to support the immune system in older people will remain essential, particularly in the face of the current COVID-19 pandemic and, thus, developing strategies to ensure adequate nutrition for the growing number of older adults will be an important and cost-effective investment in the future.

Dietary omega-3 LCPUFA intake in the prevention of neovascular age-related macular degeneration: a systematic review and meta-analysis.

Purpose: to evaluate the protective effect of omega-3 long-chain unsaturated fatty acids on the progression of wet age-related macular degeneration (wAMD). Methods: this meta-analysis was designed, implemented, and analyzed in accordance with the Meta-analysis of Observational Studies in Epidemiology (MOOSE) protocol and is reported following PRISMA guidelines. Results: in this study we included 5 observational trials, including 2 cross-sectional studies, 2 case-control studies, and 1 confrontation study. These tests are conducted in the U.S., Europe and Japan, and are of high quality. In general, people with high dietary long-chain omega-3 polyunsaturated fatty acids (omega-3 LCPUFAs) have a lower risk of progression to advanced age-related macular degeneration (AMD) (effect size, ES: 0.51, 95 % CI [0.34, 0.75], I2 = 70 %, p = 0.01). When assessing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) intake and wAMD risk a total of the three above studies were included, which also produced similar results. Conclusions: the highest DHA consumption reduced the risk of disease by 39 % (effect size: 0.61, 95 % CI [0.50, 0.74], I2 = 14 %, p = 0.31); compared with the lowest EPA consumption, the highest EPA consumption reduced the risk of wAMD by 32 % (ES: 0.68, 95 % CI [0.57, 0.82], I2 = 39 %, p = 0.20).

Potential Cardioprotective Effects and Lipid Mediator Differences in Long-Chain Omega-3 Polyunsaturated Fatty Acid Supplemented Mice Given Chemotherapy.

Many commonly used chemotherapies induce mitochondrial dysfunction in cardiac muscle, which leads to cardiotoxicity and heart failure later in life. Dietary long-chain omega-3 polyunsaturated fatty acids (LC n-3 PUFA) have demonstrated cardioprotective function in non-chemotherapy models of heart failure, potentially through the formation of LC n-3 PUFA-derived bioactive lipid metabolites. However, it is unknown whether dietary supplementation with LC n-3 PUFA can protect against chemotherapy-induced cardiotoxicity. To test this, 36 female ovariectomized C57BL/6J mice were randomized in a two-by-two factorial design to either a low (0 g/kg EPA + DHA) or high (12.2 g/kg EPA + DHA) LC n-3 PUFA diet, and received either two vehicle or two chemotherapy (9 mg/kg anthracycline + 90 mg/kg cyclophosphamide) tail vein injections separated by two weeks. Body weight and food intake were measured as well as heart gene expression and fatty acid composition. Heart mitochondria were isolated using differential centrifugation. Mitochondrial isolate oxylipin and N-acylethanolamide levels were measured by mass spectrometry after alkaline hydrolysis. LC n-3 PUFA supplementation attenuated some chemotherapy-induced differences (Myh7, Col3a1) in heart gene expression, and significantly altered various lipid species in cardiac mitochondrial preparations including several epoxy fatty acids [17(18)-EpETE] and N-acylethanolamines (arachidonoylethanolamine, AEA), suggesting a possible functional link between heart lipids and cardiotoxicity.

Common carp (Cyprinus carpio) obtain omega-3 long-chain polyunsaturated fatty acids via dietary supply and endogenous bioconversion in semi-intensive aquaculture ponds

Omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) are essential micronutrients for aquatic consumers. Synthesized by aquatic primary producers, n-3 LC-PUFA are transferred across trophic levels and may eventually end up accumulating in fish. However, if short in dietary supply, fish may also biosynthesize n-3 LC-PUFA from dietary precursors (i.e., n-3 C18-PUFA). We applied compound-specific hydrogen stable isotope analysis (CSIA) of fatty acids to investigate sources and metabolic processes of n-3 LC-PUFA, and in particular of docosahexaenoic acid (22:6n-3, DHA), in common carp (Cyprinus carpio) raised in semi-intensive aquaculture ponds. Carp were feeding on natural pond zooplankton and benthic macroinvertebrates rich in n-3 LC-PUFA and cereal-based pellet feeds rich in C18-PUFA. Results provide isotopic evidence that carp obtained a significant amount of dietary lipids and nitrogen from added cereal-based feeds, while n-3 LC-PUFA were generally acquired by feeding on benthic macroinvertebrates and zooplankton. However, DHA retained in carp was also generated endogenously via bioconversion from dietary PUFA precursors, such as EPA. DHA was isotopically lighter than EPA and likely not supplied in sufficient quantities to meet the physiological requirements for DHA in carp. Our data show that depending on the natural abundance of dietary DHA in these eutrophic ponds, farmed carp can obtain DHA by two different pathways; i.e., directly via dietary uptake and indirectly via bioconversion. This field study highlights the importance of dietary LC-PUFA supply in eutrophic aquatic ecosystems and the ability of carp to biosynthesize highly valuable LC-PUFA, eventually also benefiting human health.

Lipogenic Gene Single Nucleotide Polymorphic DNA Markers Associated with Intramuscular Fat, Fat Melting Point, and Health-Beneficial Omega-3 Long-Chain Polyunsaturated Fatty Acids in Australian Pasture-Based Bowen Genetics Forest Pastoral Angus, Hereford, and Wagyu Beef Cattle.

This study used targeted sequencing aimed at identifying single nucleotide polymorphisms (SNP) in lipogenic genes and their associations with health-beneficial omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA), intramuscular fat (IMF), and fat melting point (FMP) of the M. longissimus dorsi muscle in Australian pasture-based Bowen Genetics Forest Pastoral Angus, Hereford, and Wagyu cattle. It was hypothesized that SNP encoding for the fatty acid-binding protein 4 (FABP4), stearoyl-CoA desaturase (SCD), and fatty acid synthase (FASN) genes will be significantly associated with health-beneficial n-3 LC-PUFA and the meat eating quality traits of IMF and FMP in an Australian pasture-based beef production system. Two SNP mutations, g.21267406 T>C and g.21271264 C>A, in the SCD gene were significantly (p < 0.05) associated with IMF, FMP, oleic acid (18:1n-9), linoleic acid (LA) 18:2n-6, alpha-linolenic acid (ALA) 18:3n-3, eicosapentaenoic acid (EPA) 20:5n-3, docosahexaenoic acid (DHA) 22:6-n-3, and docosapentaenoic acid (DPA) 22:5n-3. Significant positive correlations (p < 0.05) between FASN SNP g. 50787138 A>G and FMP, 18:1n-9, ALA, EPA, DHA, DPA, and total n-3 LC-PUFA were also detected. An SNP (g.44678794 G>A) in the FABP4 gene was associated with FMP. These results provide significant insights into the contributions of lipogenic genes to intramuscular fat deposition and the biosynthesis of health-beneficial n-3 LC-PUFA. The findings also unravel the potential use of lipogenic gene polymorphisms in marker-assisted selection to improve the content of health-promoting n-3 LC-PUFA and meat eating quality traits in Australian pasture-based Bowen Genetics Forest Pastoral Angus, Hereford, and Wagyu beef cattle.

Genes regulating levels of ω-3 long-chain polyunsaturated fatty acids are associated with alcohol use disorder and consumption, and broader externalizing behavior in humans.

Individual variation in the physiological response to alcohol is predictive of an individual's likelihood to develop alcohol use disorder (AUD). Evidence from diverse model organisms indicates that the levels of long-chain polyunsaturated omega-3 fatty acids (ω-3 LC-PUFAs) can modulate the behavioral response to ethanol and therefore may impact the propensity to develop AUD. While most ω-3 LC-PUFAs come from diet, humans can produce these fatty acids from shorter chain precursors through a series of enzymatic steps. Natural variation in the genes encoding these enzymes has been shown to affect ω-3 LC-PUFA levels. We hypothesized that variation in these genes could contribute to the susceptibility to develop AUD. We identified nine genes (FADS1, FADS2, FADS3, ELOVL2, GCKR, ELOVL1, ACOX1, APOE, and PPARA) that are required to generate ω-3 LC-PUFAs and/or have been shown or predicted to affect ω-3 LC-PUFA levels. Using both set-based and gene-based analyses we examined their association with AUD and two AUD-related phenotypes, alcohol consumption, and an externalizing phenotype. We found that the set of nine genes is associated with all three phenotypes. When examined individually, GCKR, FADS2, and ACOX1 showed significant association signals with alcohol consumption. GCKR was significantly associated with AUD. ELOVL1 and APOE were associated with externalizing. Taken together with observations that dietary ω-3 LC-PUFAs can affect ethanol-related phenotypes, this work suggests that these fatty acids provide a link between the environmental and genetic influences on the risk of developing AUD.

Linking omega-3 polyunsaturated fatty acids in natural diet with brain size of wild consumers.

Omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) are key structural lipids and their dietary intake is essential for brain development of virtually all vertebrates. The importance of n-3 LC-PUFA has been demonstrated in clinical and laboratory studies, but little is known about how differences in the availability of n-3 LC-PUFA in natural prey influence brain development of wild consumers. Consumers foraging at the interface of aquatic and terrestrial food webs can differ substantially in their intake of n-3 LC-PUFA, which may lead to differences in brain development, yet this hypothesis remains to be tested. Here we use the previously demonstrated shift towards higher reliance on n-3 LC-PUFA deprived terrestrial prey of native brown trout Salmo trutta living in sympatry with invasive brook trout Salvelinus fontinalis to explore this hypothesis. We found that the content of n-3 LC-PUFA in muscle tissues of brown trout decreased with increasing consumption of n-3 LC-PUFA deprived terrestrial prey. Brain volume was positively related to the content of the n-3 LC-PUFA, docosahexaenoic acid, in muscle tissues of brown trout. Our study thus suggests that increased reliance on diets low in n-3 LC-PUFA, such as terrestrial subsidies, can have a significant negative impact on brain development of wild trout. Our findings provide the first evidence of how brains of wild vertebrate consumers response to scarcity of n-3 LC-PUFA content in natural prey.

A dose-response meta-analysis of the association between the maternal omega-3 long-chain polyunsaturated fatty acids supplement and risk of asthma/wheeze in offspring

BackgroundPrenatal exposure to omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) in oily fish may prevent asthma or wheeze in childhood.ObjectiveBy limiting n-3 LC-PUFA capsules interventions commenced in pregnancy, this systematic review aimed to find more clear evidence on the relationship between the supplement with n-3 LC-PUFA during pregnancy and the risk of asthma/wheeze in offspring and to improve the life satisfaction of children with asthma.MethodsThe Cochrane library, Embase, Medline, Web of Science, and PubMed were searched from origin to March 2021 in the above-mentioned databases. Studies selection, data of characteristics extraction, and risk of bias assessment were conducted by two authors, independently. A total of 3037 mother-infant pairs from eight randomized controlled trials were ultimately analyzed. The primary outcome was the risk of “asthma and/or wheeze”, and the secondary outcome was “Allergic asthma” in this dose-response meta-analysis. Sensitivity analysis and subgroup analysis were conducted. The robust-error meta-regression model was used for dose-response analysis.ResultsThis meta-analysis showed that n-3 LC-PUFA during pregnancy did not obviously reduce the risk of asthma/wheeze (RR 0.93; 95% CI 0.82 to 1.04, p = 0.21) and allergic asthma (RR 0.66, 95% CI 0.24 to 1.86, p = 0.44). The risk of asthma/wheeze in offspring was significantly decreased in the subgroup analysis when:: (1) studies conducted in Europe (RR 0.69; 95% CI 0.53 to 0.89); (2) daily supplementary dose of n-3 LC-PUFA was at least 1200 mg (RR 0.69; 95% CI 0.55 to 0.88); (3) supplementation lasts from pregnancy to lactation period (RR 0.69; 95% CI 0.51 to 0.95). Furthermore, the risk of asthma/wheeze reduce 2% when daily supplemental dose of n-3 LC-PUFA was increased by 100 mg in the linear dose-response analysis model.ConclusionsPerinatal supplementation with n-3 LC-PUFA can reduce the incidence of asthma/wheeze and allergic asthma in children under certain conditions, and higher doses indicate better protective effects. Further studies are required to confirm the hypothesis of an association between n-3 LC-PUFA intake and childhood asthma/wheeze prevention.

Towards Sustainable Sources of Omega-3 Long-Chain Polyunsaturated Fatty Acids in Northern Australian Tropical Crossbred Beef Steers through Single Nucleotide Polymorphisms in Lipogenic Genes for Meat Eating Quality

This study aimed to identify single nucleotide polymorphisms (SNP) in lipogenic genes of northern Australian tropically adapted crossbred beef cattle and to evaluate associations with healthy lipid traits of the Longissimus dorsi (loin eye) muscle. The hypothesis tested was that there are significant associations between SNP loci encoding for the fatty acid binding protein 4 (FABP4), stearoyl-CoA desaturase (SCD) and fatty acid synthase (FASN) genes and human health beneficial omega-3 long-chain polyunsaturated fatty acids (ω3 LC-PUFA) within the loin eye muscle of northern Australian crossbred beef cattle. Brahman, Charbray, and Droughtmaster crossbred steers were fed on Rhodes grass hay augmented with desmanthus, lucerne, or both, for 140 days and the loin eye muscle sampled for intramuscular fat (IMF), fat melting point (FMP), and fatty acid composition. Polymorphisms in FABP4, SCD, and FASN genes with significant effects on lipid traits were identified with next-generation sequencing. The GG genotype at the FABP4 g.44677239C&gt;G locus was associated with higher proportion of linoleic acid than the CC and CG genotypes (p &lt; 0.05). Multiple comparisons of genotypes at the SCD g.21266629G&gt;T locus indicated that the TT genotype had significantly higher eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids than GG genotype (p &lt; 0.05). Significant correlations (p &lt; 0.05) between FASN SNP and IMF, saturated and monounsaturated fatty acids were observed. These results provide insights into the contribution of lipogenic genes to intramuscular fat deposition and SNP marker-assisted selection for improvement of meat-eating quality, with emphasis on alternate and sustainable sources of ω3 LC-PUFA, in northern Australian tropical crossbred beef cattle, hence an acceptance of the tested hypothesis.

Comparative analysis of muscle nutrient in two types of hybrid bream and native bream

Distant hybridization can integrate parental advantages to produce new varieties, which may also improve the fish meat quality. Fish is considered to be one of the healthiest meats because it can provide rich protein sources and high levels of omega-3 long-chain polyunsaturated fatty acids. Two types of hybrid bream (BBTB and BTBB) were obtained by the two rounds of backcrossing with an established hybrid lineage of blunt snout bream (Megalobrama amblycephala, BSB, ♀) ​× ​topmouth culter (Culter alburnus, TC, ♂). In the present study, the muscle nutrients, including moisture, fat, protein and ash contents, as well as amino acid and fatty acid compositions, in BBTB, BTBB and their parent BSB with the age of four months were investigated and analyzed by biochemical methods. The results showed that the moisture content of BTBB (76.6%) was lower than that of BSB (77.4%) and BBTB (77.3%), while the protein content of BBTB (17.1%) and BTBB (17.6%) was higher than that of BSB (16.3%). Seventeen amino acids were detected in the muscles from three kinds of fish, among which total amino acids, essential amino acids and delicious amino acids in BTBB and BBTB were all to different degrees higher than those of BSB. Further analysis of fatty acids revealed that BTBB and BBTB exhibited higher levels of unsaturated fatty acids (UFAs) content and the sum content of eicosapentaenoic acid (EPA, C20:5 n-3) and docosahexaenoic acid (DHA, C22:6 n-3) in muscle than BSB. Taken together, the results showed the advantages of BBTB and BTBB in nutritional value and taste, which provided theoretical support for their production application.

Fatty Acid Composition and Cytotoxic Activity of Lipid Extracts from Nannochloropsis gaditana Produced by Green Technologies.

Microalgae are alternatives and sustainable sources of omega-3 long chain-polyunsaturated fatty acids (LC-PUFA). However, the eco-friendly extraction of these bioactives remains unexplored. In this work, the use of enzyme-based methods in combination with ultrasounds was evaluated as green approaches to extract the omega-3 lipids from Nannochloropsis gaditana. Three commercial enzymatic solutions (Viscozyme® L, Celluclast® 1.5 L, and Saczyme®) were investigated, and results were compared with the traditional Folch method. A promising extraction approach was developed by using Saczyme®, achieving a lipid yield of 25.7% ± 0.5, comparable to the traditional method (27.3% ± 0.7) (p > 0.05). Similar omega-3 content was found by GC–MS analysis for both lipid extracts (30.2% ± 2.4 and 29.3% ± 0.8 for the green and the traditional method, respectively), showing that the green approaches did not affect the fatty acid profile. Moreover, the cytotoxic activity of produced lipids was assessed by comparing human colon cancer cells (HCT-116) and epithelial nontumorigenic immortalized cells (HCEC-1CT). Results suggest that the lipid extracts have a selective effect, reducing the viability of the colon carcinoma cells but not the nontumorigenic cells. Thus, this study provides new eco-innovative approaches for extracting the omega-3 LC-PUFA from microalgae with promising biological properties.

Improved long-chain omega-3 polyunsaturated fatty acids in sago palm weevil (Rhynchophorus ferrugineus) larvae by dietary fish oil supplementation

The nutritional values of sago palm weevil larvae (SPWL) reared on mixed plant-based diets (ground sago palm trunk (GS), cornmeal, rice bran, soybean, and perilla seed), containing different levels of dietary fish oil (FO) were compared to those reared on commercial pig feed (PF) and GS. Increased FO content resulted in an increase in ω-3 fatty acids (FA) in SPWL (p < 0.05), especially α-linolenic acid and eicosapentaenoic acid. When fed FO-fortified diets instead of PF, the health-promoting indices of the SPWL lipid improved significantly (e.g., decreased ω-6/ω-3 ratio, thrombogenicity index, and hypercholesterolemic FA with increased PUFA content). The lipid, protein, and mineral contents of SPWL were increased while growth performance was maintained on a 1.5% FO-fortified diet. Higher FO levels (3–5%) had a negative impact on the nutritional values and growth performance of the SPWL. Thus, there was a reasonable chance of developing a high-nutrient alternative insect for human consumption.

In vivo biosynthesis of long-chain polyunsaturated fatty acids by the euryhaline rotifer (Brachionus plicatilis)

In order to increase omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA) availability and to improve the design of rotifer's enrichment protocols for marine larvae production, the endogenous fatty acid (FA) metabolism of the marine rotifer, Brachionus plicatilis was determined. To this purpose, the in vivo ability of this species to incorporate, esterify into the different lipid classes and to elongate/desaturate unsaturated FAs was investigated. Rotifers were incubated in 75 cm2 tissue culture flasks, at a density of 75,000 rotifers per incubation, for 4 h. Incubations (n = 4) were performed at 21 °C, with 0.3 μCi of [1-14C]FAs including C18 FAs (18:1n-9, OA; 18:2n-6, LA; 18:3n-3, ALA) and LC-PUFA (20:4n-6, ARA; 20:5n-3, EPA; 22:6n-3, DHA). The present study demonstrates that rotifers possess an active metabolism over dietary FAs, being this species able to produce LC-PUFA from its C18 FA precursors. Interestingly, the action of a Δ12 desaturase that converts OA to LA and of a Δ15 desaturase over LA to produce ALA, seems to be also present, in agreement with previously reported functional characterization of ωx desaturases genes in this species. However, a globally low transformation rate was obtained, in addition to a lower incorporation of DHA into rotifer tissues compared to the other incubated substrates. The aforementioned factors, together with a competitive esterification pattern of DHA, LA and ALA into phosphatidylcholine (PC) or of EPA and ARA into phosphatidylinositol (PI), may give rise to rotifers with inadequate essential FA ratios for marine larvae nutrition, if ignored or incorrectly handled in the lipid enrichment process of this live prey species.

The Potential of Phaeodactylum as a Natural Source of Antioxidants for Fish Oil Stabilization.

Worldwide, fish oil is an important and rich source of the health-beneficial omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). It is, however, troubled by its high susceptibility towards lipid oxidation. This can be prevented by the addition of (preferably natural) antioxidants. The current research investigates the potential of Phaeodactylum carotenoids in this regard. The oxidative stability of fish oil and fish oil with Phaeodactylum addition is evaluated by analyzing both primary (PV) and secondary (volatiles) oxidation products in an accelerated storage experiment (37 °C). A first experimental set-up shows that the addition of 2.5% (w/w) Phaeodactylum biomass is not capable of inhibiting oxidation. Although carotenoids from the Phaeodactylum biomass are measured in the fish oil phase, their presence does not suffice. In a second, more elucidating experimental set-up, fish oil is mixed in different proportions with a Phaeodactylum total lipid extract, and oxidative stability is again evaluated. It was shown that the amount of carotenoids relative to the n-3 LC-PUFA content determined oxidative stability. Systems with a fucoxanthin/n-3 LC-PUFA ratio ≥ 0.101 shows extreme oxidative stability, while systems with a fucoxanthin/n-3 LC-PUFA ratio ≤ 0.0078 are extremely oxidatively unstable. This explains why the Phaeodactylum biomass addition did not induce oxidative stability.

Correlation between intake of fish or supplements containing omega-3 fatty acids and early pregnancy plasma concentrations.

Long-chain polyunsaturated omega-3 fatty acids are considered important for fetal development, but previous studies suggest suboptimal intake in part of pregnant women in Iceland. The study aim was to evaluate intake of food and supplements containing omega-3 fatty acids, among pregnant women in Iceland and correlations to fatty acid composition in plasma. Subjects were 853 pregnant women attending their 11-14 weeks ultrasound appointment. Information on intake of food and supplements containing long-chain omega-3 fatty acids (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) as well as background was obtained by a questionnaire. Blood samples were collected for analysis of plasma fatty acids. Correlation was evaluated using the Spearman correlation. Median intake of lean fish was 1.3 times per week, while fatty fish was consumed once monthly. About 50% of the women took omega-3 containing supplements daily. Higher intake of both fish and omega-3 containing supplements was reflected in higher omega-3 plasma levels (r=0.37 p<0.001). A positive correlation was seen between intake of cod liver oil/capsules (r=0.23, p=0.001), omega-3 oil/capsules (r=0.20, p=0.001) and plasma concentration of omega-3. However, no correlation was seen between intake of a maternal multivitamin containing omega-3 and corresponding plasma concentration (r=0.03, p=0.98). Intake of food and supplements containing omega-3 fatty acids was reflected in plasma concentration, except for an Icelandic maternal multivitamin. One third of the women followed the recommendation of eating fish at least twice weekly. About 50% had a daily intake of supplements containing omega-3 fatty acids.

Photo-Oxidative Stability of Aqueous Model Systems Enriched with Omega-3 Long-Chain Polyunsaturated Fatty Acid-Rich Microalgae as Compared to Autoxidative Stability.

Several species of microalgae are promising as an alternative source of omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). Photoautotrophic species show the greatest potential, since incorporating them into food products leads to oxidatively stable products; however, the presence of photosensitizers could reduce the shelf-life due to the appearance of photo-oxidation on exposure to light. This study investigated the oxidative impact of illumination for aqueous model suspensions enriched with Phaeodactylum (phototrophic microalgae─containing potential photosensitizers) and Schizochytrium (heterotrophic microalgae─lacking photosensitizers) during storage for 28 days at 37 °C. Primary (peroxide value) and secondary (volatiles with gas chromatography (GC)-mass spectrometry) oxidation products, n-3 LC-PUFA content (GC), and pigments (high-pressure liquid chromatography) were assessed. The results showed that photo-oxidation did not cause oxidative instability for Phaeodactylum samples compared with strong autoxidation in Schizochytrium samples. For the Phaeodactylum-enriched suspensions, only minimal photo-oxidation could be detected and the n-3 LC-PUFA content remained stable throughout storage regardless of illumination.

Ratio of Omega-6/Omega-3 Polyunsaturated Fatty Acids Associated With Somatic and Depressive Symptoms in People With Painful Temporomandibular Disorder and Irritable Bowel Syndrome

Somatic symptom disturbance is among the strongest predictors of painful temporomandibular disorder (TMD). Related psychological constructs, such as anxiety and depression, respond therapeutically to omega-3 polyunsaturated fatty acids (PUFAs) in clinical trials. This cross-sectional study investigated associations between the omega-6/omega-3 PUFA ratio and somatic symptom disturbance and depressive symptoms in a community-based sample of 501 adults and determined whether these associations differed between adults with and without TMD or irritable bowel syndrome (IBS). Liquid chromatography tandem mass spectrometry quantified PUFAs in circulating erythrocytes. Somatic symptoms and depression were quantified using Symptom Checklist-90-Revised subscales. Presence or absence of TMD and IBS, respectively, were determined by clinical examination and Rome III screening questions. The standardized beta coefficient for the omega-6/omega-3 long-chain PUFA ratio was 0.26 (95% confidence limits (CL): 0.08, 0.43) in a multivariable linear regression model in which somatic symptom disturbance was the dependent variable. When modelling depressive symptoms as the dependent variable, the standardized beta coefficient was 0.17 (95% CL:0.01, 0.34). Both associations were stronger among TMD cases and IBS cases than among non-cases. Future randomized control trials that lower the omega-6/omega-3 PUFA ratio could consider somatic or depressive symptoms as a therapeutic target for TMD or IBS pain. PerspectiveIn people with TMD or IBS, a high n-6/n-3 PUFA ratio was positively associated with somatic symptom disturbance and depressive symptoms. Both measures of psychological distress were elevated in people with painful TMD and IBS. Future randomized clinical trials will determine whether lowering the n-6/n-3 ratio is therapeutic for pain.

Editors' Note: Fish Intake and MRI Burden of Cerebrovascular Disease in Older Adults

In “Fish intake and MRI burden of cerebrovascular disease in older adults,” Thomas et al. reported that higher fish intake was associated with lower burden of cerebrovascular disease, particularly in subjects aged <75 years. Brenner commented that these findings might be attributed to lower consumption of red meat and dairy products, which contain glycolyneuraminic acid (Neu5Gc), a sialic acid that can cause chronic inflammation leading to atherosclerosis. Thomas and Samieri agreed that red meat and dairy products can lead to cerebrovascular disease, but noted that they adjusted for these and other confounders such as intake of fruit, vegetables, legumes, and olive oil. As such, they believe that their findings are directly attributed to higher fish intake, rather than lower intake of red meat and dairy. They reported that this may be due to the main beneficial effects of long-chain omega-3 polyunsaturated fatty acids. In “Fish intake and MRI burden of cerebrovascular disease in older adults,” Thomas et al. reported that higher fish intake was associated with lower burden of cerebrovascular disease, particularly in subjects aged <75 years. Brenner commented that these findings might be attributed to lower consumption of red meat and dairy products, which contain glycolyneuraminic acid (Neu5Gc), a sialic acid that can cause chronic inflammation leading to atherosclerosis. Thomas and Samieri agreed that red meat and dairy products can lead to cerebrovascular disease, but noted that they adjusted for these and other confounders such as intake of fruit, vegetables, legumes, and olive oil. As such, they believe that their findings are directly attributed to higher fish intake, rather than lower intake of red meat and dairy. They reported that this may be due to the main beneficial effects of long-chain omega-3 polyunsaturated fatty acids.