Chain Omega-3 Research Articles

PSIX-6 Algal oil as an alternative source of docosahexaenoic acid in feline diets

Abstract The global demand for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation by humans and their necessity in companion animal foods has raised questions related to environmental sustainability and nutrient content of fish oil. The combination of reported diminishing EPA and DHA content in fish oil and the forecasting of a significant decline in global fish stocks over the next decade make it critical to consider alternative sources of omega-3 fatty acids to reduce dependence on fish harvests. Cultured algal oil has been identified as a promising and viable alternative to fish-based oils. As such, the purpose of this study was to determine the inclusion level of algal oil in cat foods necessary to deliver the same serum concentrations of DHA provided from fish oil. Cats (n = 26) were first fed a control food formulated to avoid ingredients that contain long chain omega-3 fatty acids [ɑ-linolenic (ALA), EPA, and DHA] for 5 wk, to establish a baseline serum concentrations of these fatty acids. Cats were then randomized into two groups, and fed test foods containing either fish oil or algal oil in sequential increasing levels of DHA (0.2%, 0.4%, and 0.6%) for 5-wk periods each. Blood was analyzed for serum DHA and EPA concentrations after each of these feeding periods. A regression analysis was used to calculate a bioequivalence factor between fish oil and algal oil inclusion levels. There was no difference (P > 0.05) in intake or body weight between cats consuming diets containing algal oil or fish oil. Analysis of serum fatty acid concentrations showed that increasing fish and algal oil had no effect (P > 0.05) on serum linolenic acid, ALA, or arachidonic acid; however, increasing fish and algal oil did have an effect on DHA such that serum DHA was increased at similar rates as fish oil (P = 0.050) and algal oil (P = 0.026) levels were increased in the diet. Although increasing levels of fish and algal oil both increased serum EPA concentrations (P < 0.001), fish oil increased serum EPA to a greater extent than algal oil when fed at all levels. Overall, these data indicate that inclusion of algal oil is a good alternative dietary source of DHA, but less of EPA, and that algal oil will need to be added to the diet in higher concentrations to achieve similar serum EPA concentrations as fish oil.

A Low Omega-3 Index and High AA/EPA Ratio in American College Football Players are Both Improved Following 5 Weeks of DHA-Rich Algae Oil Supplementation

Abstract Purpose Many athletes are deficient in long chain omega-3 polyunsaturated fatty acids (LC n-3 PUFA). A consequent low Omega-3 Index (O3I) and high arachidonic acid/eicosapentaenoic acid (AA/EPA) ratio increase cardiovascular disease risk and inflammation. Algae oil is a plant-based, sustainable source of LC n-3 PUFA, suitable for vegans and vegetarians. Effects of algae oil supplementation on whole blood fatty acids among athletes has not been previously reported. This study evaluated the effects of 5 weeks of DHA-rich algae oil supplementation on the whole blood fatty acid profile, O3I and AA/EPA ratio of omnivorous Division I American College Football (ACF) players. Methods: Data, including a spot blood sample, were collected at baseline for all participants (n = 47), then for a subset of players (n = 22) following a 5-week control period (usual diet) and 5 weeks of algae oil supplementation (usual diet + 1575 mg docosahexaenoic acid (DHA) + eicosapentaenoic acid (EPA) 5 days/week; average 1125 mg/day). Results: Baseline O3I was 4.3% ± 0.1% and AA/EPA ratio was 45.6 ± 23.8. After 5 weeks of algae oil supplementation, the O3I was 6.1% ± 1.0% and the AA/EPA ratio was 25.1 ± 11.6. The O3I was significantly higher and the AA/EPA ratio was significantly lower (P < 0.0001 for both) compared with both baseline and the end of the control period. The increase in O3I from baseline was correlated with calculated DHA + EPA dose per unit body mass (R = 0.641, P = 0.001). Conclusions: Algae oil supplementation for 5 weeks improved both the low baseline O3I and high AA/EPA ratio among ACF players, with body mass specific dose effects.

The knowledge, attitudes, and behaviours of pregnant women regarding seafood consumption during the antenatal period: a qualitative study

BackgroundMaternal nutrition impacts fetal growth and development. The Food Standards Australia New Zealand (FSANZ) guidelines recommend pregnant women consume 2–3 servings (224–336 g) of fish/seafood per week to support intake of long chain omega 3 fatty acids, given adequate consumption supports numerous health benefits including reduced risk of preterm and early preterm birth. Evidence indicates that pregnant women purposely lower their fish/seafood intake, largely due to fears of methylmercury exposure. The aim of this study was to explore pregnant women’s knowledge, attitudes, and behaviours regarding their fish/seafood consumption during the antenatal period.MethodsSemi-structured interviews were conducted between October 2018 and December 2020 among a purposive sample of 12 pregnant women from the Australian Capital Territory (ACT). The interviews were recorded, transcribed verbatim, and analysed using an interpretative phenomenological approach. Themes were developed on the women’s lived experience related to fish/seafood knowledge, attitudes, and consumption behaviour.ResultsThe most prominent finding was widespread non-adherence to fish/seafood consumption guidelines. This was largely owing to a lack of proactive health promotion related to the health benefits of fish/seafood throughout pregnancy, including the health promoting roles of long chain omega 3 fatty acids for fetal growth and development. Three themes were identified: nutrition knowledge; sources of health promotion; and barriers and enablers to fish/seafood consumption.ConclusionsTo support adequate maternal consumption of fish/seafood throughout pregnancy, emphasis should be placed on the benefits of consuming this food group regularly. Additionally, pregnant women should receive education about the health promoting role of long chain omega 3 fatty acids. Dietitians are well placed to provide this information.

Essential Amino Acid, Short Chain Fatty Acid and Omega Content of Skipjack Tuna Offal Meal and its Effects on the Nutrient Digestibility of Local Chicken

Essential Amino Acid, Short Chain Fatty Acid and Omega Content of Skipjack Tuna Offal Meal and its Effects on the Nutrient Digestibility of Local Chicken

Monocyte transcriptomic profile following EPA and DHA supplementation in men and women with low-grade chronic inflammation

BackgroundRecent data indicate considerable variability in response to very long chain omega-3 fatty acid supplementation on cardiovascular disease risk. This inconsistency may be due to differential effects of EPA vs DHA and/or sex-specific responses. MethodsSixteen subjects (eight men and eight women) 50–75 y and with low-grade chronic inflammation participated in a randomized controlled crossover trial comparing 3 g/d EPA, 3 g/d DHA, and placebo (3 g/d high oleic acid sunflower oil). Blood monocytes were isolated at the end of each phase for RNA-sequencing. ResultsSex dimorphism in monocyte gene expression was observed, therefore, data for men and women were analyzed separately. 1088 genes were differentially expressed in men and 997 in women (p < 0.05). In both men and women, EPA and DHA repressed genes involved in protein turnover and mitochondrial energy metabolism, relative to placebo. In men only, EPA and DHA upregulated genes related to wound healing and PPARα activation. In women only, EPA and DHA activated genes related to ER stress response. Relative to DHA, EPA resulted in lower expression of genes involved in inflammatory processes in men, and lower expression of genes involved in ER stress response in women. ConclusionsEPA and DHA supplementation elicited both similar and differential effects on monocyte transcriptome, some of which were sex specific. The observed variability in response to EPA and DHA in men and women could in part explain the conflicting results from previous cardiovascular clinical trials using omega-3 fatty acids.

Fish and Omega-3 Fatty Acids: Sex and Racial Differences in Cardiovascular Outcomes and Cognitive Function.

Both cardiovascular disease (CVD) and cognitive decline are common features of aging. One in 5 deaths is cardiac for both men and women in the United States, and an estimated 50 million are currently living with dementia worldwide. In this review, we summarize sex and racial differences in the role of fish and its very long chain omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in preventing CVD events and cognitive decline. In prospective studies, women with higher nonfried and fatty fish intake and women and Black individuals with higher plasma levels of EPA and DHA had a lower risk of CVD. In randomized controlled trials of EPA and DHA supplementation in primary CVD prevention, Black subjects benefited in a secondary outcome. In secondary CVD prevention, both men and women benefited, and Asians benefited as a prespecified subgroup. Fish and omega-3 polyunsaturated fatty acids are associated with prevention of cognitive decline in prospective studies. In randomized controlled trials of EPA and DHA supplementation, women have cognitive benefit. DHA seems more beneficial than EPA, and supplementation is more beneficial when started before cognitive decline. Although studies in women and racial groups are limited, life-long intake of nonfried and fatty fish lowers the risk of CVD and cognitive decline, and randomized controlled trials also show the benefit of EPA and DHA supplementation. These findings should be factored into recommendations for future research and clinical recommendations as dietary modalities could be cost-effective for disease prevention.

DHA, nutrient intake, and maternal characteristics as predictors of pregnancy outcomes in a randomised clinical trial of DHA supplementation

To investigate the relationships among docosahexaenoic acid (DHA) intake, nutrient intake, and maternal characteristics on pregnancy outcomes in a phase III randomised clinical trial designed to determine the effect of a DHA dose of 1000mg/day compared to 200mg/day on early preterm birth (<34 weeks gestation). A secondary aim of the phase III randomised trial was to explore the relationships among pregnancy outcomes (maternal red blood cell phospholipid (RBC-PL) DHA at delivery, preterm birth, gestational age at delivery, labor type, birth anthropometric measures, low birth weight, gestational diabetes, pre-eclampsia, and admission to a neonatal intensive care unit) in participants (n=1100). We used Bayesian multiple imputation and linear and logistic regression models to conduct an analysis of five general classes of predictor variables collected during the trial: a) DHA intake, b) nutrient intake from food and supplements, c) environmental exposure to tobacco and alcohol, d) maternal demographics, and e) maternal medical history. DHA supplementation lowered the risk of preterm birth and NICU admission, and increased gestation and birth weight as observed in the primary analysis. Higher maternal RBC-PL-DHA at delivery was associated with DHA supplementation and formal education of a bachelor's degree or higher. DHA supplementation and maternal age were associated with a higher risk of gestational diabetes. Total vitamin A intake was associated with longer gestation, while fructose and intake of the long chain omega-6 fatty acid, arachidonic acid, were associated with shorter gestation. Risk of preterm birth was associated with a history of low birth weight, preterm birth, pre-eclampsia, and NICU admission. Bayesian models provide a comprehensive approach to relationships among DHA intake, nutrient intake, maternal characteristics, and pregnancy outcomes. We observed previously unreported relationships between gestation duration and fructose, vitamin A, and arachidonic acid that could be the basis for future research. ClinicalTrials.gov (NCT02626299); December 10, 2015.

Extrusion processing improves rainbow trout digestibility of microalgal Nannochloropsis oculata co-product biomass for more sustainable aquaculture diets

Aquaculture feeds include fishmeal (FM) and fish oil (FO), derived from wild-caught marine fish such as anchovy and sardines, and pose ecological, food security, and economic drawbacks for sustainable aquaculture, the world's fastest-growing agricultural sector. Protein-rich microalgal co-product is a promising alternative to unsustainably sourced fishmeal in aquaculture diets. Microalgal co-product is a defatted biomass left over after extracting omega-3-rich oil for human nutraceuticals and crude oil for fuels. In this study, we report the first evaluations of nutritive values and digestibility of raw, extrusion- and enzymatic-processed co-product of the marine microalga Nannochloropsis oculata (N. oculata co-product). Results allowed us to evaluate the feasibility of using processed biomass in aquafeed for rainbow trout (Oncorhynchus mykiss), an important model for all salmonid aquaculture. Extrusion processing temperature (90 °C vs 127 °C) influenced the nutritional value of N. oculata. Protein and energy levels were significantly higher in co-product from both extrusion temperature treatments than in non-extruded raw co-product. Essential amino acid levels did not differ between extrusion temperatures, except that methionine was significantly lower in coproduct from 127 °C extrusion processing than from 90 °C extrusion processing. The protein level in extrusion processed co-product was not significantly influenced by pre-cooking. We detected the highest digestibility of crude protein, energy, most of the amino acids, and omega 3 polyunsaturated fatty acids (n3 PUFA) in extruded (90 °C) N. oculata co-product ingredient. Nutrient digestibility of enzymatic processed N. oculata co-product were mostly the same as extrusion processing or lower for certain nutrients. Overall, extrusion processing of N. oculata at 90 °C provided the best outcome for digestible protein, and yielded an excellent source of digestible protein, amino acids, and long chain omega-3 profile for rainbow trout and which could be an alternative to replace fishmeal in rainbow trout diets.

Effect of Tyrosol Acyl Esters on the Antioxidant Status of Mussel (Mytilus edulis) Oil During Accelerated Oxidative Storage

ABSTRACT The effect of tyrosol (Tyr) and tyrosol acyl ester (TYr-Es) on thiobarbituric acid reactive substance, peroxide value, acid value, aldehyde content, fatty acid composition, and tyrosol content of mussel (Mytilus edulis) oil (MO) during accelerated storage at 60°C was evaluated. The results indicated that TYr-Es and TYr showed effective protection of MO against lipid oxidation. However, the poor solubility of TYr may lead to the formation of a suspension in oils. Therefore, TYr-Es with good lipid solubility and oxidation resistance may serve as potential antioxidant in marine oils highly enriched in long chain omega-3 polyunsaturated fatty acids in phospholipid form.

Different Diets Based on Yellow Mealworm (Tenebrio molitor)—Part B: Modification of the Intestinal Inflammatory Response and the Microbiota Composition of Rainbow Trout (Oncorhynchus mykiss)

With the purpose of improving aquaculture sustainability, the search for protein alternatives to fishmeal makes it necessary to test different variables and the possible repercussions of new ingredients. The use of insect meal as a protein source for aquaculture is well described, but the complex composition of insect meals (fat and other components) can affect the physiology of fish. For this reason, as a part of a bigger study, the aim of the current manuscript was to test diets based on three different presentations of insect meal coming from yellow mealworm (Tenebrio molitor): full fat, partially defatted, and supplemented with a long chain omega–3-enriched oil, and to evaluate their effects on protein digestibility, biometric indices, immunological system and gut health (intestinal histomorphology and microbiota) of rainbow trout (Oncorhynchus mykiss). Digestibility of the protein and body indices showed a minor but consistent trend. The non-specific immunological system did not show changes, but the histology of the intestine showed signs that insect meals could be softening a mild inflammatory response. The gut microbiota suffered several changes, which could be associated with the different amino acid and fatty acid compositions of the diets.

Full replacement of fish oil with algae oil in farmed Atlantic salmon (Salmo salar) – Debottlenecking omega 3

The global goal of developing sustainable aquafeed has faced increased complexity in sourcing raw materials. The limited availability of fish oil (FO) is a well-known bottleneck for the aquaculture industry and pairing it with EFSA (EFSA CONTAM, 2018) reduced tolerable weekly intake of marine contaminants [polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) and dioxin-like polychlorinated biphenyls (DLPCB)] creates another challenge for wild caught FO and its use in fish feed. In recent years, commercial algal alternatives have increasingly become available. Not only would omega-3 sources from algae reduce the reliance on FO; it would allow for restoration of the long chain omega-3 levels in farmed salmon. To this end, a study was conducted to establish knowledge on full replacement of FO by algae oil (Schizochytrium sp.) in Atlantic salmon with the aim of reducing contaminants levels in the fillet and maintaining the level of omega-3 fatty acid (FA), growth performance, health, and final product quality. Atlantic salmon (531 g) were distributed into twelve 5 × 5 × 5 m sea cages and fed one of four diets for 369 days: a control diet (Control) containing FO + rapeseed oil (VO1); a diet where AlgaPrime (AP) replaced 50% of the sum of EPA + DHA from FO (50AP + VO1); a diet where AP replaced 100% of the sum of EPA + DHA from FO (100AP + VO1), and a diet the same as the previous but using linseed instead of rapeseed oil (VO2; 100AP + VO2). All diets were balanced for key micronutrients. At the end of the trial, zootechnical parameters were obtained, health and welfare assessed, and final fillet quality analysed for contaminants and fillet quality post slaughter. Full replacement of FO significantly reduced the levels of PCDD/F and DLPCB in the fillet of 4 kg salmon by 70% and 79% respectively for 100AP + VO1 and 40% and 43% respectively for 100AP + VO2 fed fish. Fish gained an average of 3.7 kg across treatments (average final weight 4235.8 g ± 191.8); almost an 8-fold increase for all treatments. No significant differences were found among diets for performance, feed intake, gut health, histology, welfare, pigmentation, or fillet quality. This study demonstrates that AlgaPrime can be used to fully replace FO in Atlantic salmon grower feed without negative effects, achieving an important impact on food safety and sustainability for aquafeed producers and salmon consumers.

Literature review: nutrition supplementation for muscle fatigue in athletes

The use of natural or conventional-based supplementation has become a popular strategy among athletes seeking to reduce oxidative stress, improve recovery, and enhance athletic performance. This literature review searched four reputable international electronic databases, including PubMed, MedRxiv, Cochrane, and Clinical Trial.gov until December 2021, using Boolean operators with keywords and Mesh methods. The keywords used were "Supplementation", AND "Muscle Fatigue Recovery", AND "Athletes", which yielded 24 articles as study findings. The literature review found that exhaustive exercise can induce a neutrophil antioxidant response by increasing antioxidant enzymes. Nutritional supplements, specifically antioxidant supplements, Branched Chain Amino Acid (BCAA), citrulline, omega-3, and caffeine, have been scientifically proven to reduce oxidative damage, which can block signaling pathways related to muscle hypertrophy. In order to combat muscle fatigue in athletes based on this research (literature review), natural ingredients and synthetic nutritional supplements have been utilized as dietary interventions. This literature review identified numerous natural micronutrients and synthetic supplements used in sports that possess anti-fatigue properties, decrease oxidative stress and enhance athletes' endurance capacity. The effectiveness of nutritional supplements in addressing muscle fatigue may vary based on the various ingredients in the supplements. However, natural-based supplements have become a preferred option among athletes and coaches currently.

Comparison of Ahiflower oil containing stearidonic acid to a high-alpha-linolenic acid flaxseed oil at two dietary levels on omega-3 enrichment of egg yolk and tissues in laying hens.

Enrichment of egg yolks with very long chain omega-3 fatty acids (VLCn-3 FA) is of interest because of their beneficial effects on human health. The ability of Ahiflower® oil (AHI; Buglossoides arvensis), which is naturally rich in stearidonic acid (SDA), and a high-alpha-linolenic acid (ALA) flaxseed (FLAX) oil to enrich eggs and tissues of laying hens with VLCn-3 FA was investigated. Forty 54-week-old Hy-Line W-36 White Leghorn hens were fed a diet that contained soybean oil (control; CON) or AHI or FLAX oils at 7.5 or 22.5 g/kg of the diet in substitution for the soybean oil for 28 days. Dietary treatments had no effects on egg number or components or follicle development. Total VLCn-3 FA contents of egg yolk, liver, breast, thigh, and adipose tissue were greater in the n-3 treatments compared to CON, with the greatest increase observed at the higher oil level, especially for AHI oil which had the greater VLCn-3 enrichment than FLAX in yolk (p < 0.001). Efficiency of VLCn-3 enrichment of egg yolks was decreased with n-3 oils and by increasing oil level with lowest efficiency at 22.5 g/kg FLAX. In conclusion, both SDA-rich (AHI) and ALA-rich (FLAX) oils increased VLCn-3 FA deposition into egg yolks and hens' tissues, but dietary AHI oil promoted a greater enrichment than comparative amounts of FLAX oil, especially in liver and egg yolks.

Lower omega-3 status associated with higher erythrocyte distribution width and neutrophil-lymphocyte ratio in UK Biobank cohort

High red blood distribution width (RDW) is associated with decreased red blood cell deformability, and high neutrophil-lymphocyte ratio (NLR) is a biomarker of systemic inflammation and innate-adaptive immune system imbalance. Both RDW and NLR are predictors of chronic disease risk and mortality. Omega-3 index (O3I) values have previously been shown to be inversely associated with RDW and NLR levels. Our objective was to determine if total plasma long chain omega-3 fatty acids (Omega3%) measured in the UK Biobank cohort were associated with RDW and NLR values. RDW- and NLR- relationships with Omega3% were characterized in 109,191 adults (58.4% female). RDW- and NLR-Omega3% relationships were inversely associated with Omega3% (both p < 0.0001). These cross-sectional associations confirm previous findings that increasing RDW and NLR values are associated with low O3I. The hypothesis that RDW and/or NLR values can be reduced in individuals with less-than optimal long chain omega 3 values need to be tested in randomized controlled intervention trials using EPA and/or DHA.

Changes in fatty acids during storage of artisanal-processed freshwater sardines (Rastrineobola argentea).

For ages, indigenous small fish species have been important in food and nutritional security of poor communities in low income countries. Freshwater fish, in particular fatty fish species are attracting a great attention because they are good sources of health promoting long chain omega-3 fatty acids. Docosahexaenoic acid (DHA, C22:6n-3), Docosapentaenoic acid (DPA, C22:5n-3) and eicosapentaenoic acid (EPA, C20:5n-3) are the main omega-3 PUFAs known to confer health benefits in humans if consumed in required amounts. While nutritionally valued, omega-3 PUFAs in fish are susceptible to oxidative damage during processing, transportation and subsequent storage. Lake Victoria sardines (Rastrineobola argentea), are rich source of chemically unstable omega-3 fatty acids DHA, DPA and EPA. Traditionally, sardines are preserved by sun drying, deep frying and smoking. Sardine products are transported, stored and marketed at ambient temperatures. Generally, uncontrolled and higher temperatures are known to increase vulnerability of polyunsaturated fatty acids to oxidation which in turn results into loss of nutritional and sensory qualities. This study investigated changes of fat acids in sun dried, deep fried and smoked sardines during storage. Lipolysis and the progressive hydroperoxides formation were monitored by free fatty acids (FFAs) and peroxide value (PV) respectively. None volatile secondary products of lipid oxidation were measured by thiobabituric acid reactive substances (TBARS). Fatty acids were analyzed by gas chromatography with a flameionization detector (GC-FID). Deep fried sardines maintained the lowest and apparently stable PV, TBARS and FFAs. Proportions of saturated fatty acids and polyunsaturated fatty acids decreased with time while that of monounsaturated fatty acids increased. Omega-3 fatty acids EPA, DPA and DHA decreased with increase in storage time. In 21 days of storage, DHA was oxidized beyond detectable levels in all sardine products. Gradual increase in FFAs in sun dried sardines was suggestive of lipid hydrolysis induced by enzymes.

Comparison of Fish, Krill and Flaxseed as Omega-3 Sources to Increase the Omega-3 Index in Dogs

(1) Background: it is only the longer chain omega-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (20:5n-3, EPA), and docosahexaenoic acid (22:6n-3, DHA) and not the shorter chain α-linolenic acid (ALA, 18:3n-3) that have been linked to health benefits. (2) Methods: 45 dogs divided into three groups were first given premium dry food for 38 days (baseline). The O3I was then used as a diagnostic tool to provide a measure of the sum of EPA + DHA in red blood cell membranes given as a percentage of all fatty acids. The dogs were subsequently fed with either krill meal (krill), fishmeal/oil (fish) or flaxseed cake (flax) included in raw food providing daily 416 mg EPA + DHA (971 mg ALA), 513 mg EPA + DHA (1027 mg ALA) and 1465 mg ALA (122 mg EPA + DHA), respectively. (3) Results: the average baseline O3I level of all dogs was low (1.36%), warranting n-3 supplementation. After four weeks, O3I levels were significantly increased in the krill (from 1.36 ± 0.44 to 2.36 ± 0.39%) and fish (from 1.35 ± 0.22 to 1.9 ± 0.35%) groups (p < 0.001). No significant modification of the O3I was detected in the flax animals. (4) Conclusions: only marine n-3 PUFAs resulted in a significantly increased O3I, with dietary krill meal providing the highest increase.

Dysregulated hepatic lipid metabolism and gut microbiota associated with early-stage NAFLD in ASPP2-deficiency mice

Growing evidence indicates that lipid metabolism disorders and gut microbiota dysbiosis were related to the progression of non-alcoholic fatty liver disease (NAFLD). Apoptosis-stimulating p53 protein 2 (ASPP2) has been reported to protect against hepatocyte injury by regulating the lipid metabolism, but the mechanisms remain largely unknown. In this study, we investigate the effect of ASPP2 deficiency on NAFLD, lipid metabolism and gut microbiota using ASPP2 globally heterozygous knockout (ASPP2+/-) mice. ASPP2+/- Balb/c mice were fed with methionine and choline deficient diet for 3, 10 and 40 day to induce an early and later-stage of NAFLD, respectively. Fresh fecal samples were collected and followed by 16S rRNA sequencing. HPLC-MRM relative quantification analysis was used to identify changes in hepatic lipid profiles. The expression level of innate immunity-, lipid metabolism- and intestinal permeability-related genes were determined. A spearman's rank correlation analysis was performed to identify possible correlation between hepatic medium and long-chain fatty acid and gut microbiota in ASPP2-deficiency mice. Compared with the WT control, ASPP2-deficiency mice developed moderate steatosis at day 10 and severe steatosis at day 40. The levels of hepatic long chain omega-3 fatty acid, eicosapentaenoic (EPA, 20:5 n-3) and docosahexaenoic (DHA, 22:6 n-3), were decreased at day 10 and increased at day 40 in ASPP+/- mice. Fecal microbiota analysis showed significantly increased alpha and beta diversity, as well as the composition of gut microbiota at the phylum, class, order, family, genus, species levels in ASPP2+/- mice. Moreover, ASPP-deficiency mice exhibited impaired intestinal barrier function, reduced expression of genes associated with chemical barrier (REG3B, REG3G, Lysozyme and IAP), and increased expression of innate immune components (TLR4 and TLR2). Furthermore, correlation analysis between gut microbiota and fatty acids revealed that EPA was significantly negatively correlated with Bifidobacterium family. Our findings suggested that ASPP2-deficiency promotes the progression of NAFLD, alterations in fatty acid metabolism and gut microbiota dysbiosis. The long chain fatty acid EPA was significantly negatively correlated with Bifidobacterial abundance, which is a specific feature of NAFLD in ASPP2-deficiency mice. Totally, the results provide evidence for a mechanism of ASPP2 on dysregulation of fatty acid metabolism and gut microbiota dysbiosis.

Single cell analysis of docosahexaenoic acid suppression of sequential LPS-induced proinflammatory and interferon-regulated gene expression in the macrophage.

Preclinical and clinical studies suggest that consumption of long chain omega-3 polyunsaturated fatty acids (PUFAs) reduces severity of chronic inflammatory and autoimmune diseases. While these ameliorative effects are conventionally associated with downregulated expression of proinflammatory cytokine and chemokine genes, our laboratory has recently identified Type 1 interferon (IFN1)-regulated gene expression to be another key target of omega-3 PUFAs. Here we used single cell RNA sequencing (scRNAseq) to gain new mechanistic perspectives on how the omega-3 PUFA docosahexaenoic acid (DHA) influences TLR4-driven proinflammatory and IFN1-regulated gene expression in a novel self-renewing murine fetal liver-derived macrophage (FLM) model. FLMs were cultured with 25 µM DHA or vehicle for 24h, treated with modest concentration of LPS (20 ng/ml) for 1 and 4h, and then subjected to scRNAseq using the 10X Chromium System. At 0h (i.e., in the absence of LPS), DHA increased expression of genes associated with the NRF2 antioxidant response (e.g. Sqstm1, Hmox1, Chchd10) and metal homeostasis (e.g.Mt1, Mt2, Ftl1, Fth1), both of which are consistent with DHA-induced polarization of FLMs to a more anti-inflammatory phenotype. At 1h post-LPS treatment, DHA inhibited LPS-induced cholesterol synthesis genes (e.g. Scd1, Scd2, Pmvk, Cyp51, Hmgcs1, and Fdps) which potentially could contribute to interference with TLR4-mediated inflammatory signaling. At 4h post-LPS treatment, LPS-treated FLMs reflected a more robust inflammatory response including upregulation of proinflammatory cytokine (e.g. Il1a, Il1b, Tnf) and chemokine (e.g.Ccl2, Ccl3, Ccl4, Ccl7) genes as well as IFN1-regulated genes (e.g. Irf7, Mx1, Oasl1, Ifit1), many of which were suppressed by DHA. Using single-cell regulatory network inference and clustering (SCENIC) to identify gene expression networks, we found DHA modestly downregulated LPS-induced expression of NF-κB-target genes. Importantly, LPS induced a subset of FLMs simultaneously expressing NF-κB- and IRF7/STAT1/STAT2-target genes that were conspicuously absent in DHA-pretreated FLMs. Thus, DHA potently targeted both the NF-κB and the IFN1 responses. Altogether, scRNAseq generated a valuable dataset that provides new insights into multiple overlapping mechanisms by which DHA may transcriptionally or post-transcriptionally regulate LPS-induced proinflammatory and IFN1-driven responses in macrophages.

Production of fungal biomass from oat flour for the use as a nutritious food source

Fermentation can be a powerful tool for developing new sustainable foods with increased nutritional value and fermented microbial biomass derived from filamentous fungi is a promising example. This study investigates the nutritional profile of edible Aspergillus oryzae biomass produced under submerged fermentation (SmF) using oat flour as a substrate. The fermentation occurred in a 1m3 airlift bioreactor during 48 h at 35 °C and the nutritional profile of the produced fungal biomass in terms of amino acids, fatty acids, minerals (Fe, Zn, Cu, Mn), vitamins (E, D2), and dietary fiber was compared to oat flour as well as pure fungal biomass grown on semi-synthetic medium. The total amount of amino acids increased from 11% per dry weight (dw) in oat flour to 23.5% dw in oat fungal biomass with an improved relative ratio of essential amino acids (0.37 to 0.42). An increase in dietary fibers, minerals (Fe, Zn, Cu), vitamin E, as well as vitamin D2 were also obtained in the oat fungal biomass compared to oat flour. Moreover, the short chain omega-3 α-linolenic acid (ALA) and omega-6 linoleic acid (LA) values increased from 0.6 to 8.4 and 21.7 to 68.4 (mg/g dry weight sample), respectively, in oat fungal biomass. The results indicate that fungal biomass grown on oat flour could have a potential application in the food industry as a nutritious source for a wide variety of products.

Dysregulation of Subcutaneous White Adipose Tissue Inflammatory Environment Modelling in Non-Insulin Resistant Obesity and Responses to Omega-3 Fatty Acids - A Double Blind, Randomised Clinical Trial.

BackgroundObesity is associated with enhanced lipid accumulation and the expansion of adipose tissue accompanied by hypoxia and inflammatory signalling. Investigation in human subcutaneous white adipose tissue (scWAT) in people living with obesity in which metabolic complications such as insulin resistance are yet to manifest is limited, and the mechanisms by which these processes are dysregulated are not well elucidated. Long chain omega-3 polyunsaturated fatty acids (LC n-3 PUFAs) have been shown to modulate the expression of genes associated with lipid accumulation and collagen deposition and reduce the number of inflammatory macrophages in adipose tissue from individuals with insulin resistance. Therefore, these lipids may have positive actions on obesity associated scWAT hypertrophy and inflammation.MethodsTo evaluate obesity-associated tissue remodelling and responses to LC n-3 PUFAs, abdominal scWAT biopsies were collected from normal weight individuals and those living with obesity prior to and following 12-week intervention with marine LC n-3 PUFAs (1.1 g EPA + 0.8 g DHA daily). RNA sequencing, qRT-PCR, and histochemical staining were used to assess remodelling- and inflammatory-associated gene expression, tissue morphology and macrophage infiltration.ResultsObesity was associated with scWAT hypertrophy (P < 0.001), hypoxia, remodelling, and inflammatory macrophage infiltration (P = 0.023). Furthermore, we highlight the novel dysregulation of Wnt signalling in scWAT in non-insulin resistant obesity. LC n-3 PUFAs beneficially modulated the scWAT environment through downregulating the expression of genes associated with inflammatory and remodelling pathways (P <0.001), but there were altered outcomes in individuals living with obesity in comparison to normal weight individuals.ConclusionOur data identify dysregulation of Wnt signalling, hypoxia, and hypertrophy, and enhanced macrophage infiltration in scWAT in non-insulin resistant obesity. LC n-3 PUFAs modulate some of these processes, especially in normal weight individuals which may be preventative and limit the development of restrictive and inflammatory scWAT in the development of obesity. We conclude that a higher dose or longer duration of LC n-3 PUFA intervention may be needed to reduce obesity-associated scWAT inflammation and promote tissue homeostasis.Clinical Trial Registration www.isrctn.com, identifier ISRCTN96712688.