Dietary PUFA Research Articles

Association of serum fatty acids with bone health in rural elderly population in Qingdao, China: A cross-sectional study.

As a type of macronutrient, fatty acids (FA) play significant roles in the bone health of elderly people. However, the specific association between different types of FA and bone health is not fully understood, especially in rural elderly populations. To address this gap, a study was conducted in rural areas of Qingdao, China. Participants aged 65 and older were randomly recruited from 11 rural villages in Licha town, Qingdao City. The levels of serum FA in their serum were measured to investigate the associations between FA and bone mass. The results showed that levels of saturated fatty acids (SFA), n-3 polyunsaturated fatty acids (n-3 PUFA), and n-6 polyunsaturated fatty acids (n-6 PUFA) were all significantly associated with bone mass. Specifically, higher levels of SFA were positively correlated with low bone mass (LBM), while PUFA levels were inversely correlated with LBM. Furthermore, the odds ratio (OR) for LBM exhibited a significant nonlinear dose-response relationship (pnonlinearity = 0.1989) with SFA levels, and a significant nonlinear dose-dependent relationship was also observed with the levels of n-3PUFA and n-6PUFA (pnonlinearity = 0.6183, 0.5808, respectively), indicating that increasing dietary PUFA intake appropriately and controlling SFA intake may benefit the bone health of elderly individuals in rural areas.

Crucial Interactions between Altered Plasma Trace Elements and Fatty Acids Unbalance Ratio to Management of Systemic Arterial Hypertension in Diabetic Patients: Focus on Endothelial Dysfunction.

The coexistence of SAH with T2DM is a common comorbidity. In this study, we investigated the link between altered plasma antioxidant trace elements (ATE: manganese, selenium, zinc, and copper) and fatty acids ratio (FAR: polyunsaturated/saturated) imbalance as transition biomarkers between vascular pathology (SAH) to metabolic pathology (T2DM). Our data revealed strong correlation between plasma ATE and FAR profile, which is modified during SAH-T2DM association compared to the healthy group. This relationship is mediated by lipotoxicity (simultaneously prominent visceral adipose tissue lipolysis, significant flow of non-esterified free fatty acids release, TG-Chol-dyslipidemia, high association of total SFA, palmitic acid, arachidonic acid, and PUFA ω6/PUFA ω3; drop in tandem of PUFA/SFA and EPA + DHA); oxidative stress (lipid peroxidation confirmed by TAS depletion and MDA rise, concurrent drop of Zn/Cu-SOD, GPx, GSH, Se, Zn, Se/Mn, Zn/Cu; concomitant enhancement of Cu, Mn, and Fe); endothelial dysfunction (endotheline-1 increase); athero-thrombogenesis risk (concomitant rise of ApoB100/ApoA1, Ox-LDL, tHcy, and Lp(a)), and inflammation (higher of Hs-CRP, fibrinogen and ferritin). Our study opens to new therapeutic targets and to better dietary management, such as to establishing dietary ATE and PUFA ω6/PUFA ω3 or PUFA/SFA reference values for atherosclerotic risk prevention in hypertensive/diabetic patients.

Sustainable Livestock Farming with Oil Seed Crops and Their By-Products

The increasing human population and food shortage are fueling the demand for alternative feed resources for animals not meant for human consumption. Oil seeds and their derivatives are suitable options to meet the escalating global demand for animal feed proteins; camelina is one of them. Camelina sativa (CS), an ancient oilseed crop belonging to the Brassicaceae family, is known for its resistance to drought and cold, as well as its various uses for meal, oil, and other products. However, it also has some anti-nutritional factors (ANF) that can limit its use as animal feed. These ANFs can be reduced by various methods, such as enzyme addition, heat treatment, fermentation, or genetic engineering. CS and its by-products can affect animal metabolism, especially lipid metabolism and hormone levels, and can also improve the fat profile of meat and milk products, making them more suitable for human consumption and health. CS and its by-products achieved weight gain and protected dietary PUFAs, but decreased bio-hydrogenation intermediates. Small ruminants fed CS-supplemented diets produced meat with a suitable fat profile for human consumption. Feeding with CS seeds and derivatives decreased milk fat concentration, yield, and fat-corrected milk. Camelina forage, however, increased the milk fat percentage. The effects of CS and its by-products on milk fatty acid composition were contradictory. CS meals may improve the composition of milk products, making them healthier for humans. Researchers need to determine how CS meals can be used in dairy ewe and goat diets at different life stages.

The effect of various dietary MUFA content and n-6/n-3 ratios on rainbow trout (Oncorhynchus mykiss) fed on a whole plant protein based diet: growth performance, digestive enzymes activity, intestinal morphometry and fatty acids profile of muscle and liver.

The effect of diets with various dietary MUFA content and n-6/n-3 ratios, diets 1 (55.33, 1.00), 2 (25.30, 1.00), 3 (55.13, 2.05), 4 (24.92, 2.03), 5 (54.94, 8.06) and 6 (24.91, 8.06) and a control diet with fish oil (FO), diet 7 (33.60, 5.97), was studied on growth and digestive physiology of rainbow trout, Oncorhynchus mykiss. Juveniles, 14.65g ± 0.17, were fed the experimental diets for eight weeks. Those fish fed diet 1 (55.33, 1.00) had the lowest growth and nutritional indices, while fish fed diet 6 (24.91, 8.06) possessed the highest indices. However, fish fed D7 (33.60, 5.97) was intermediate in this regard. Proximate body composition results revealed no significant differences among various experimental groups (P > 0.05). Fish fed on diet 1 possessed the highest alkaline protease activity, while fish raised on diet 2 showed the lowest enzyme activity (P < 0.05). Fish fed on diets 1, 3 and 4 had the highest lipase activity (P > 0.05). Amylase activity and intestinal parameters did not differ among groups (P > 0.05). MUFA contents of liver and muscle reflected the MUFA contents of the diets; however, liver PUFA contents was not affected by dietary PUFA contents (P < 0.05). However, 18:3n-3 contents of liver decreased as dietary n-6/n-3 ratio increased (P < 0.05). Furthermore, the liver 20:4n-6 contents considerably increased as dietary n-6/n-3 increased to 8.06 (P < 0.05). Muscle 22:6n-3 content of groups 1 to 6 was lower than group 7 (P < 0.05). In conclusion, rainbow trout was considerably capable of de novo synthesis of 22:6n-3. Meanwhile, increasing dietary n-6/n-3 ratio to 8.06 decreased the muscle 22:6n-3 content which requires further considerations regarding fish immune competence and nutritional quality for human consumption.

The Proximate Composition, Mineral and Pectin Content and Fatty Acid Profile of the Pomace Fraction of 16 Rowanberry Cultivars

The berry pomace could be a potential source for food applications due to its high content of polyphenols, but also dietary fiber, PUFAs and pectin. This is the first study that aims to compare the total dietary fiber (TDF), protein, fat, mineral, pectin and fatty acid content of the following 16 different pomace samples of Sorbus aucuparia L. cultivars (cvs): ‘Likernaja’, ‘Burka’, ‘Alaja Krupnaja’, ‘Granatnaja’, ‘Rubinovaja’, ‘Bussinka’, ‘Vefed’, ‘Angri’, ‘Krasnaja’, ‘Solnechnaja’, ‘Sahharnaja’, ‘Oranzevaja’, ‘Kubovaja’, ‘Moravica’, ‘Rosina’ and ‘Rossica’, in order to find new natural materials for valorization. The contents of pectin and dietary fibers were analyzed using the respective Megazyme enzymatic kits. The TDF content was the highest in the pomace samples of hybrid cvs ‘Granatnaja’ (63.04% dry mass DM), ‘Burka’ (64.52% DM), ‘Rubinovaja’ (65.66% DM) and ‘Likernaja’ (67.17% DM). The pomace of hybrid cv ‘Rubinovaja’ was distinguished from other samples by its high protein content, cv ‘Alaja Krupnaja’ by its high pectin content and cv ‘Oranzevaja’ by its high fat content, which were 7.58% DM, 8.39% DM and 7.47% DM, respectively. The pomace of cv ‘Sahharnaja’ possessed the highest average macro-element content (1.56 g/kg DM). The average fatty acids profile was characterized by a high content of linoleic acid (51.94%), oleic acid (20.55%) and palmitic acid (12.96%). The lowest n6/n3 ratio was found in the hybrid cv ‘Alaja Krupnaja’ (6.70%). The data obtained demonstrate that the pomaces of certain cultivars of rowanberry contain significant amounts of valuable components, which can be used in functional food and cosmetic applications.

Dietary polyunsaturated fatty acids intake is negatively associated with hyperuricemia: The National Health and Nutrition Examination Survey 2003–2015

Background and aimsThe objective of this research was to explore the associations between dietary PUFAs intake and hyperuricemia risk. Methods and resultsBased on the National Health and Nutrition Examination Survey (NHANES) 2003–2015, all eligible individuals were divided into hyperuricemia and non-hyperuricemia groups based on diagnostic criteria for hyperuricemia (serum uric acid >420 μmol/L for men and >360 μmol/L for women). Multivariate-adjusted logistic regression was employed to explore the relationship between dietary PUFAs intake and hyperuricemia risk. Total PUFAs and their subtypes were modeled to isocalorically replace saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs). Higher intake of n-3 PUFAs, n-6 PUFAs, linoleic acid (LA), alpha-linoleic acid (ALA), and non-marine PUFAs intake correlated with decreased hyperuricemia risk, with adjusted odds ratio (OR) and 95% confidence interval (95%CIs) were 0.77 (0.63, 0.93), 0.75 (0.61, 0.92), 0.75 (0.61, 0.91), 0.69 (0.55, 0.87), and 0.73 (0.59, 0.91), respectively. Replacing 5% of total energy intake from SFAs with isocaloric PUFAs was associated with decreased odds of hyperuricemia in men (0.69 (0.57, 0.84)) and in individuals (0.81 (0.71, 0.92)). Similar trends were observed in the substitution of SFAs with non-marine PUFAs in men (0.87 (0.80, 0.94)) and in all individuals (0.92 (0.88, 0.98)). Sensitivity analyses exhibited consistent results with primary analyses. ConclusionHigher dietary intake of n-3 PUFAs, n-6 PUFAs, LA, ALA, and non-marine PUFAs was associated with decreased hyperuricemia risk. These results support the recommendation to substitute SFAs with PUFAs in diet.

Dietary fatty acids modulate oxidative stress response to air pollution but not to infection.

Anthropogenic changes to the environment expose wildlife to many pollutants. Among these, tropospheric ozone is of global concern and a highly potent pro-oxidant. In addition, human activities include several other implications for wildlife, e.g., changed food availability and changed distribution of pathogens in cities. These co-occurring habitat changes may interact, thereby modulating the physiological responses and costs related to anthropogenic change. For instance, many food items associated with humans (e.g., food waste and feeders for wild birds) contain relatively more ω6-than ω3-polyunsaturated fatty acids (PUFAs). Metabolites derived from ω6-PUFAs can enhance inflammation and oxidative stress towards a stimulus, whereas the opposite response is linked to ω3-derived metabolites. Hence, we hypothesized that differential intake of ω6-and ω3-PUFAs modulates the oxidative stress state of birds and thereby affects the responses towards pro-oxidants. To test this, we manipulated dietary ω6:ω3 ratios and ozone levels in a full-factorial experiment using captive zebra finches (Taeniopygia guttata). Additionally, we simulated an infection, thereby also triggering the immune system's adaptive pro-oxidant release (i.e., oxidative burst), by injecting lipopolysaccharide. Under normal air conditions, the ω3-diet birds had a lower antioxidant ratio (GSH/GSSG ratio) compared to the ω6-diet birds. When exposed to ozone, however, the diet effect disappeared. Instead, ozone exposure overall reduced the total concentration of the key antioxidant glutathione (tGSH). Moreover, the birds on the ω6-rich diet had an overall higher antioxidant capacity (OXY) compared to birds fed a ω3-rich diet. Interestingly, only the immune challenge increased oxidative damage, suggesting the oxidative burst of the immune system overrides the other pro-oxidative processes, including diet. Taken together, our results show that ozone, dietary PUFAs, and infection all affect the redox-system, but in different ways, suggesting that the underlying responses are decoupled despite that they all increase pro-oxidant exposure or generation. Despite lack of apparent cumulative effect in the independent biomarkers, the combined single effects could together reduce overall cellular functioning and efficiency over time in wild birds exposed to pathogens, ozone, and anthropogenic food sources.

Integrated analysis revealing novel associations between dietary patterns and the immune system in older adults.

With the expanding ageing population, there is a growing interest in the maintenance of immune health to support healthy ageing. Enthusiasm exists for unravelling the impact of diet on the immune system and its therapeutic potential. However, a key challenge is the lack of studies investigating the effect of dietary patterns and nutrients on immune responses. Thus, we have used an integrative analysis approach to improve our understanding of diet-immune system interactions in older adults. To do so, dietary data were collected in parallel with performing immunophenotyping and functional assays from healthy older (n = 40) participants. Food Frequency Questionnaire (FFQ) was utilised to derive food group intake and multi-colour flow cytometry was performed for immune phenotypic and functional analysis. Spearman correlation revealed the strength of association between all combinations of dietary components, micronutrients, and hallmarks of immunesenescence. In this study, we propose for the first time that higher adherence to the Mediterranean diet is associated with a positive immune-ageing trajectory (Lower IMM-AGE score) in older adults due to the immune protective effects of high dietary fibre and PUFA intake in combating accumulation or pro-inflammatory senescent T cells. Furthermore, a diet rich in Vit A, Vit B6 and Vit B12 is associated with fewer features of immunesenescence [such as accumulation of terminally differentiated memory CD8 T cells] in older adults. Based on our findings we propose a future nutrition-based intervention study evaluating the efficacy of adherence to the MED dietalongside a multi-nutrient supplementation on immune ageing in older adults to set reliable dietary recommendations with policymakers that can be given to geriatricians and older adults. Insight box: There is a growing interest in the maintenance of immune health to boost healthy ageing. However, a key challenge is the lack of studies investigating the effect of dietary patterns and nutrients on immune responses. Thus, to do so we collected dietary data in parallel with performing immunophenotyping and functional assays on healthy older (n = 40) participants, followed by an integrative analysis approach to improve our understanding of diet-immune system interactions in older adults. We strongly believe that these new findings are appropriate for IB and will be of considerable interest to its broad audience.

Lipidomic Profile of Human Sperm Membrane Identifies a Clustering of Lipids Associated with Semen Quality and Function.

Reduced sperm motility and/or count are among the major causes of reduced fertility in men, and sperm membranes play an important role in the spermatogenesis and fertilization processes. However, the impact of sperm lipid composition on male fertility remains under-investigated. The aim of the present study was to perform a lipidomic analysis of human sperm membranes: we performed an untargeted analysis of membrane lipid composition in fertile (N = 33) and infertile subjects (N = 29). In parallel, we evaluated their serum lipid levels. Twenty-one lipids were identified by their mass/charge ratio and post-source decay spectra. Sulfogalactosylglycerolipid (SGG, seminolipid) was the most abundant lipid component in the membranes. In addition, we observed a significant proportion of PUFAs. Important differences have emerged between the fertile and infertile groups, leading to the identification of a lipid cluster that was associated with semen parameters. Among these, cholesterol sulfate, SGG, and PUFAs represented the most important predictors of semen quality. No association was found between the serum and sperm lipids. Dietary PUFAs and SGG have acknowledged antioxidant functions and could, therefore, represent sensitive markers of sperm quality and testicular function. Altogether, these results underline the important role of sperm membrane lipids, which act independently of serum lipids levels and may rather represent an independent marker of reproductive function.

Effect of Low Protein Diets Supplemented with Sodium Butyrate, Medium-Chain Fatty Acids, or n-3 Polyunsaturated Fatty Acids on the Growth Performance, Immune Function, and Microbiome of Weaned Piglets.

This study aimed to investigate the effects of low-protein (LP) diets supplemented with sodium butyrate (SB), medium-chain fatty acids (MCT), or n-3 polyunsaturated fatty acids (n-3 PUFA) on the growth performance, immune function, and the microbiome of weaned piglets. A total of 120 healthy weaned piglets ((Landrace × Large White × Duroc); 7.93 ± 0.7 kg initial body weight), were randomly divided into five groups. Each group consisted of six replications with four piglets per replication. Dietary treatments included control diet (CON); LP diet (LP); LP + 0.2% SB diet (LP + SB); LP + 0.2% MCT diet (LP + MCT); and LP + PUFA diet (LP + PUFA). The experimental period lasted for 4 weeks. Compared with the CON diet, LP, LP + SB, LP + MCT, and LP + PUFA diets decreased the final weight and average daily gain (ADG) of piglets (p < 0.05). There were lower (p < 0.05) concentrations of IL-8 and higher (p < 0.05) Glutathione peroxidase (GSH-Px) activity in the plasma of piglets fed with LP + SB, LP + MCT, and LP + PUFA diets than those fed with the LP diet. The piglets in the LP + SB and LP + PUFA groups had lower IKK-alpha (IKKa) mRNA expression in the colonic mucosa compared with those in the CON and LP groups (p < 0.05). The mRNA expression of TLR4 in the colonic mucosa of piglets in the LP + SB, LP + MCT, and LP + PUFA groups was decreased when compared with the CON and LP groups (p < 0.05). The LP + MCT diets increased the gene expression of nuclear factor erythroid 2-related factor 2 (Nrf2) in the colonic mucosa of piglets compared with CON, LP, and LP + SB diets (p < 0.05). The abundance of Erysipelotrichaceae in the colonic microbiome of piglets in the LP group was higher than that in the other four groups (p < 0.05). Collectively, this study showed that LP diets supplemented with SB, MCT, or n-3 PUFA reduced plasma inflammatory factor levels, increased plasma GSH-Px activity, and declined mRNA expression of TLR4 and IKKa in the colonic epithelium, whereas it reduced the abundance of Erysipelotrichaceae in the colon of piglets.

Isolation of intake mediated effects demonstrate that the phenomic benefits of dietary omega-3 are nominal to Atlantic salmon when reared in a challenging (hypoxic) environment

The present study was designed to examine whether challenging environmental conditions (such as hypoxia) influence a fish's response to diet by changing responses to nutrient utilisation or down-regulation of appetite. To examine this, post-smolt Atlantic salmon (138.8 ± 0.65 g/fish; mean ± SD) were fed sub- (2.6% TFA; Ln3) and optimal (6.0% TFA; Hn3) levels of long-chain polyunsaturated omega-3 fatty acids (n-3 LC-PUFA) when maintained under either normoxic (8.1 ± 0.6 mg/L) or hypoxic (6.8 ± 0.5 mg/L) environmental conditions. To control for the anticipated effects of hypoxia on appetite and food intake, two additional treatments included the two diets that were pair-fed to the same intake levels as in the hypoxic treatments. The reduction in dissolved oxygen was accompanied by an increase in dissolved CO2 and decline in seawater pH, with no change in total alkalinity. After 138 days of the study the fish increased their average weight to between 616 and 720 g/fish subject to treatment. Hypoxia had a significant negative impact on final weight and weight gain, and these were the result primarily of effects on feed intake. No effects of treatments on feed conversion were observed. Significant diet x oxygen interactions were observed on whole-body lipid levels, but no other proximate compositional parameters. Sub-clinical effects of hypoxia and ration on several plasma chemistry parameters were observed, but few responses were diet related. Hypoxia affected plasma total protein, cholesterol, and red blood cell counts. Diet digestibility was typically not affected by hypoxia or ration, though a range of diet related effects were evident. Nutrient retention data showed evidence of elongation and desaturation of dietary short-chain PUFA, with clear effects of diet affecting the deposition of both omega-6 and omega-3 fatty acids. This study builds on findings from earlier studies, but crucially now include controls for the feed intake effects to clarify the roles of hypoxia on the nutrient and intake mediated effects. As a result of these controls, it is now clearer that many of the phenomic responses to long-chain omega-3 by Atlantic salmon are nominal and are largely unaffected by challenging environmental conditions like hypoxia. The inclusion of a series of pair-fed treatments, matching the feed intake levels of corresponding hypoxic treatments, shows that the effects of n-3 LC-PUFA appear to be largely intake mediated effects for Atlantic salmon post-smolts.

Dietary fatty acids and flight-training influence the expression of the eicosanoid hormone prostacyclin in songbirds

Diet shifts can alter tissue fatty acid composition in birds, which is subsequently related to metabolic patterns. Eicosanoids, short-lived fatty acid-derived hormones, have been proposed to mediate these relationships but neither baseline concentrations nor the responses to diet and exercise have been measured in songbirds. We quantified a stable derivative of the vasodilatory eicosanoid prostacyclin in the plasma of male European Starlings (Sturnus vulgaris, N = 25) fed semisynthetic diets with either high (PUFA) or low (MUFA) amounts of n6 fatty acid precursors to prostacyclin. Plasma samples were taken from each bird before, immediately after, and two days following a 15-day flight-training regimen that a subset of birds (N = 17) underwent. We found elevated prostacyclin levels in flight-trained birds fed the PUFA diet compared to those fed the MUFA diet and a positive relationship between prostacyclin and body condition, indexed by fat score. Prostacyclin concentrations also significantly decreased at the final time point. These results are consistent with the proposed influences of precursor availability (i.e., dietary fatty acids) and regulatory feedback associated with exercise (i.e., fuel supply and inflammation), and suggest that prostacyclin may be an important mediator of dietary influence on songbird physiology.

Blood and tissue docosahexaenoic acid (DHA, 22:6n-3) turnover rates from Ahiflower® oil are not different than from DHA ethyl ester oil in a diet switch mouse model

Ahiflower® oil is high in α-linolenic and stearidonic acids, however, tissue/blood docosahexaenoic acid (DHA, 22:6n-3) turnover from dietary Ahiflower oil has not been investigated. In this study, we use compound-specific isotope analysis to determine tissue DHA synthesis/turnover from Ahiflower, flaxseed and DHA oils. Pregnant BALB/c mice (13–17 days) were placed on a 2 % algal DHA oil diet of high carbon-13 content (δ13C) and pups (n = 132) were maintained on the diet until 9 weeks old. Mice were then randomly allocated to a low δ13C-n-3 PUFA diet of either: 1) 4 % Ahiflower oil, 2) 4.35 % flaxseed oil or 3) 1 % fish DHA ethyl ester oil for 1, 3, 7, 14, 30, 60 or 120 days (n = 6). Serum, liver, adipose and brains were collected and DHA levels and δ13C were determined. DHA concentrations were highest (p < 0.05) in the liver and adipose of DHA-fed animals with no diet differences in serum or brain (p > 0.05). Based on the presence or absence of overlapping 95 % C.I.'s, DHA half-lives and synthesis/turnover rates were not different between Ahiflower and DHA diets in the liver, adipose or brain. DHA half-lives and synthesis/turnover rates from flaxseed oil were significantly slower than from the DHA diet in all serum/tissues. These findings suggest that the distinct Ahiflower oil n-3 PUFA composition could support tissue DHA needs at a similar rate to dietary DHA, making it a unique plant-based dietary option for maintaining DHA turnover comparably to dietary DHA.

Growth and fatty acid composition of pikeperch (Sander lucioperca L., 1758) larvae under altered feeding protocol including the copepod Apocyclops panamensis (Marsh, 1913)

Alternative live feeds for small and sensitive fish early life stages such as pikeperch (Sander lucioperca L., 1758) can improve the larval quantity, quality and performance in aquaculture. Therefore, this study evaluated the cyclopoid copepod Apocyclops panamensis (Marsh, 1913) as live feed for pikeperch larviculture from day 11 post hatch (dph) in two independent experiments. In both experiments, pikeperch larvae had the highest specific growth rate (SGR) when they fed on Brachionus plicatilis until dph 11 and A. panamensis until dph 16–18. SGR was related to a decrease in total fatty acids (FAs), saturated FAs and monounsaturated FAs in pikeperch larvae, indicating their use as energy for growth. Within the polyunsaturated FAs, docosahexaenoic acid (DHA) increased in larvae fed with A. panamensis and coincided with the highest SGR suggesting that DHA is accumulated in larvae as structural FA. Our study demonstrated a suitable pikeperch larval fatty acid composition for growth after feeding A. panamensis compared with Artemia sp. from dph 11 until dph 16 and previously fed with B. plicatilis. Moreover, it highlighted the importance of the dietary PUFAs in pikeperch rearing, specifically of linoleic acid (LA) from dph 4 until dph 11 and of DHA from dph 11 onwards.

Sexual dimorphism in the context of nutrition and health.

Diets and dietary constituents that we consume have a considerable impact on disease risk. Intriguingly these effects may be modulated to some extent by sex. Lack of female representation in nutritional studies as well as a lack of stratification by sex has and continues to limit our understanding of these sex × diet interactions. Here we provide an overview of the current and available literature describing how exposure to certain dietary patterns (Western-style diet, Mediterranean diet, vegetarian/vegan, ketogenic diet) and dietary constituents (dietary fibre, PUFA and plant bioactive) influences disease risk in a sex-specific manner. Interestingly, these sex differences appear to be highly disease-specific. The identification of such sex differences in response to diet stresses the importance of sex stratification in nutritional research.

Fatty Acid Composition of a Maternal Diet and Erythrocyte Phospholipid Status in Latvian Pregnant Women.

Dietary fats are essential for maternal and fetal health. Fatty acids (FAs) in erythrocytes characterize the FA profile, which is influenced by diet and other factors. The aim of this study was to evaluate the association between the main FAs in erythrocyte membrane phospholipids and their influencing factors-dietary fat and supplement intake and lifestyle factors-in Latvian pregnant women. This cross-sectional study included 236 pregnant and postpartum women. The data were collected from medical documentation, a food frequency questionnaire, and a questionnaire on demographic, lifestyle, health status, and nutritional habits in outpatient clinics and maternity departments. FAs in erythrocyte membrane phospholipids were determined using gas chromatography. Correlations were found between dietary SFAs and erythrocyte SFAs (r = -0.140, p = 0.032) and PUFAs (r = 0.167, p = 0.01) and between dietary PUFAs and erythrocyte MUFAs (r = -0.143, p = 0.028). Dietary SFAs, MUFAs, and PUFAs positively correlated with the studied n-3 and n-6 FAs in erythrocytes. Vitamin D correlated positively with MUFA and negatively with total PUFA and AA in erythrocytes. There was a negative correlation between dietary vitamin A and linoleic acid in erythrocytes. Physical activity negatively correlated with erythrocyte MUFAs and positively with erythrocyte PUFAs. Alcohol consumption positively correlated with erythrocyte SFAs and negatively with erythrocyte PUFAs. There are indications that some dietary FAs may be correlated with erythrocyte FAs. Possible influencing factors for this association are alcohol, physical activity, vitamin D, and vitamin A.

Dietary Docosahexaenoic Acid and Glucose Systemic Metabolic Changes in the Mouse.

The endocannabinoid system (ECS) participates in regulating whole body energy balance. Overactivation of the ECS has been associated with the negative consequence of obesity and type 2 diabetes. Since activators of the ECS rely on lipid-derived ligands, an investigation was conducted to determine whether dietary PUFA could influence the ECS to affect glucose clearance by measuring metabolites of macronutrient metabolism. C57/blk6 mice were fed a control or DHA-enriched semi-purified diet for a period of 112 d. Plasma, skeletal muscle, and liver were collected after 56 d and 112 d of feeding the diets for metabolomics analysis. Key findings characterized a shift in glucose metabolism and greater catabolism of fatty acids in mice fed the DHA diet. Glucose use and promotion of fatty acids as substrate were found based on levels of metabolic pathway intermediates and altered metabolic changes related to pathway flux with DHA feeding. Greater levels of DHA-derived glycerol lipids were found subsequently leading to the decrease of arachidonate-derived endocannabinoids (eCB). Levels of 1- and 2-arachidonylglcerol eCB in muscle and liver were lower in the DHA diet group compared to controls. These findings demonstrate that DHA feeding in mice alters macronutrient metabolism and may restore ECS tone by lowering arachidonic acid derived eCB.

Metabolomics Biomarkers for Fatty Acid Intake and Biomarker-Calibrated Fatty Acid Associations with Chronic Disease Risk in Postmenopausal Women

BackgroundA substantial observational literature relating specific fatty acid classes to chronic disease risk may be limited by its reliance on self-reported dietary data. ObjectivesWe aimed to develop biomarkers for saturated (SFA), monounsaturated (MUFA), and polyunsaturated (PUFA) fatty acid densities, and to study their associations with cardiovascular disease (CVD), cancer, and type 2 diabetes (T2D) in Women’s Health Initiative (WHI) cohorts. MethodsBiomarker equations were based primarily on serum and urine metabolomics profiles from an embedded WHI human feeding study (n = 153). Calibration equations were based on biomarker values in a WHI nutritional biomarker study (n = 436). Calibrated intakes were assessed in relation to disease incidence in larger WHI cohorts (n = 81,894). Participants were postmenopausal women, aged 50–79 when enrolled at 40 United States Clinical Centers (1993–1998), with a follow-up period of ∼20 y. ResultsBiomarker equations meeting criteria were developed for SFA, MUFA, and PUFA densities. That for SFA density depended somewhat weakly on metabolite profiles. On the basis of our metabolomics platforms, biomarkers were insensitive to trans fatty acid intake. Calibration equations meeting criteria were developed for SFA and PUFA density, but not for MUFA density. With or without biomarker calibration, SFA density was associated positively with risk of CVD, cancer, and T2D, but with small hazard ratios, and CVD associations were not statistically significant after controlling for other dietary variables, including trans fatty acid and fiber intake. Following this same control, PUFA density was not significantly associated with CVD risk, but there were positive associations for some cancers and T2D, with or without biomarker calibration. ConclusionsHigher SFA and PUFA diets were associated with null or somewhat higher risk for clinical outcomes considered in this population of postmenopausal United States women. Further research is needed to develop even stronger biomarkers for these fatty acid densities and their major components.This study is registered with clinicaltrials.gov identifier: NCT00000611.

Impact of FADS gene variation and dietary fatty acid exposure on biochemical and anthropomorphic phenotypes in a Hispanic/Latino cohort.

Polyunsaturated fatty acids (PUFA) and highly unsaturated fatty acid (HUFA) synthetic products and their signaling metabolites play vital roles in immunity, inflammation, and brain development/function. Frequency differences of variants within the fatty acid desaturase (FADS) gene cluster affect levels of HUFAs, their biologically active products, and numerous physiological phenotypes. Fundamental questions remain regarding the impact of this genetic variation on the health of Hispanic/Latino populations. Data and biospecimens (plasma, red blood cells, buffy coat-derived DNA) from 135 participants (83.7% female) were used to assess the relationship(s) between dietary PUFA levels, a FADS haplotype tagging SNP, rs174537, and the capacity of Hispanic/Latino populations to generate HUFAs in plasma and RBC as well as its potential impact on anthropomorphic phenotypes. The dietary habits of the cohort showed that participant diets contained a high ratio (9.3 ± 0.2, mean ± SEM) of linoleic acid (n-6) to alpha-linolenic acid (n-3) and also contained extremely low levels of n-3 HUFAs (eicosapentaenoic acid, EPA and docosahexaenoic acid, DHA), both features of the Modern Western Diet. Compared to African and European American cohorts, the frequency of the TT rs174537 genotype was highly enriched (53% of subjects) in this Hispanic/Latino cohort and was strongly associated with lower circulating HUFA levels. For example, plasma levels of arachidonic acid (ARA: 20:4, n-6) and EPA (20:5, n-3) were 37% and 23%, respectively, lower in the TT versus the GG genotype. HUFA biosynthetic efficiency, as determined by metabolic product to precursor ratios, was highly dependent (p < 0.0001) on the rs174537 genotype (GG > GT > TT) for both circulating n-6 and n-3 HUFAs. In contrast, the RBC Omega-3 Index (EPA + DHA) was extremely low (2.89 ± 1.65, mean ± sd) in this population and independent of rs174537 genotype. Importantly, the rs174537 genotype was also related to female height with TT genotype participants being 4.5 cm shorter (p = 0.0001) than the GG + GT participants. Taken together, this study illustrates that dietary PUFA + HUFA × FADS gene- interactions place a large proportion (>50%) of Hispanic/Latino populations at high risk of a deficiency in both circulating and cellular levels of n-3 HUFAs.

Compound‐specific stable isotopes resolve sources and fate of polyunsaturated fatty acids in biota of headwater streams

Abstract Organisms at the base of stream food webs are typically poor in long‐chain polyunsaturated fatty acids (LC‐PUFA), especially in docosahexaenoic acid (DHA), whereas consumers at higher trophic levels are often rich in LC‐PUFA. For example, fish tissues, especially the brain, are DHA‐rich. This obvious mismatch between consumer LC‐PUFA and their basal dietary supply may result from selective retention and/or endogenous conversion of dietary precursors to LC‐PUFA. To determine which is more likely, we investigated compound‐specific carbon stable isotopes in PUFA (δ13CPUFA) of potential basal resources (stream epilithon, leaf litter) and consumers (invertebrates, European bullhead, and two salmonid species and their brain, eye, liver, and muscle tissues). We predicted that consumer‐PUFA, depleted in 13C values relative to their dietary sources, would indicate internal de novo PUFA synthesis. Alternatively, higher consumer‐δ13CPUFA values would imply selective retention of aquatic (epilithon and conditioned leaves) rather than terrestrial resources or internal production, irrespective of trophic levels. Invertebrate grazers and predators resembled δ13C values of essential fatty acids (δ13CEFA) of benthic algae, while shredder‐δ13CEFA values reflected those of conditioned rather than fresh leaves. Lower eye‐δ13CEFA values of salmonids than in livers indicated high retention of dietary PUFA sources (invertebrates and epilithon). Stable isotope values of eicosapentaenoic acid suggest that all consumers retained algal EPA, while insectivorous fish produced DHA in their liver. There is no further evidence from carbon stable isotopes for local PUFA conversion within neural tissues. Our study demonstrates that δ13CPUFA can be used to track sources of these highly functional molecules in aquatic consumers and highlights the importance of algal derived‐PUFA for these consumers in oligotrophic headwater streams.