Dietary Fish Oil Supplementation Research Articles

Sarcoplasmic Proteome Changes in Response to Aging and Diet

We seek to establish the change in the sarcoplasmic proteome the rat medial gastrocnemius (MG), as a function of age and dietary fish oil enriched diet. Physiological and behavioral measures were acquired in conjunction with quantitative two‐dimensional gel electrophoresis (2D PAGE) and immunoblotting (IB) of muscle sarcoplasm extracts. Significant proteomic changes were observed across experimental groups: young adult (8–9 months) and aged (22–23 months) S‐D rats assigned to control (Ctl) or Fish oil‐supplemented (FO) diets for 8 weeks (7 adult; 6 aged rats/group).Forelimb grip strength was assessed before & after the 8‐week diet. In situ twitch and tetanic (100 Hz) forces were assessed at completion. MG samples were extracted and the sarcoplasmic protein fraction analyzed by 2D PAGE and the integrated spot intensity analyzed. Spots showing significant changes (± ≥ 2.00, p < 0.05) were identified by HPLC/MS. For IB, PVDF blots were probed with primary antibody, then stripped and reprobed for GAPDH (loading control). Animal use and all procedures were approved by the Ohio Univ IACUC, and the “Principles of Laboratory Animal Care” (NIH Pub No. 86‐23, rev 1985), were followed throughout the study. Data were analyzed by 2 × 2 ANOVA (age × dietary group), except for grip strength, which was assessed using a repeated measures ANOVA, with time as the repeated factor.Body mass was reduced with age, but food intake did not differ across groups. Based on food disappearance, rats in the FO group ingested ~1.12 g/kg FO, with no age‐difference. There was an overall trend (P = 0.089) for FO maintaining greater grip strength vs. Ctl over time. Aged animals exhibited comparable significant reduction in MG mass and twitch & tetanic (15–20%). FO diet significantly increased tetanic (P = 0.046) but not twitch force (P = 0.262), despite having no effect on muscle mass. Twitch and tetanic force, when normalized to MG anatomical cross‐sectional area, exhibited a significant diet × age interaction (P = 0.027) and a strong trend (P = 0.051) for an effect of diet, respectively. Protein changes were classified into meta‐KOG groupings: Metabolic: 54%, Oxidative Stress: 20%, Cytoskeletal: 13% and Misc: 13%. Overall, Age × Diet interactions influenced energy metabolism proteins: CKM ‐ muscle creatine kinase; TPI 1 ‐ isoform 1 ‐ triose phosphate isomerase; DJ1 ‐ a protein deglycase; PKM ‐ muscle pyruvate kinase; BE ‐ beta enolase; NADHD ‐ NADH dehydrogenase. In Ctl conditions, CKM, NADHD and PKM were elevated in the old vs. young; BE was reduced and DJ1 and TPI1 were not different; In response to dietary FO, CKM and NADHD increased for the young and decreased for the old; BE decreased in the young only; TPI increased in the young only; DJ1 decreased in the young and increased in the old and PKM decreased in the old only.An 8‐week FO diet produced some mass‐independent improvements in muscle function and performance in young and aged rats. FO affected the expression of several proteins in young and aged MG muscle, predominantly ones related to energy metabolism.Support or Funding InformationSmith Coll Blakeslee Fund and SURF, and Ohio Univ Coll Health Sci and Professions Res Dean's Innovation ChallengeThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Standard Reference Material (SRM) 2378 fatty acids in frozen human serum. Certification of a clinical SRM based on endogenous supplementation of polyunsaturated fatty acids.

Dietary fatty acids can be both beneficial and detrimental to human health depending on the degree and type of saturation. Healthcare providers and research scientists monitor the fatty acid content of human plasma and serum as an indicator of health status and diet. In addition, both the Centers for Disease Control & Prevention (CDC) and the National Institutes of Health - Office of Dietary Supplements are interested in circulating fatty acids (FAs) because they may be predictive of coronary heart disease. The National Institute of Standards and Technology (NIST) provides a wide variety of reference materials (RMs) and Standard Reference Materials® (SRM®s) including blood, serum, plasma, and urine with values assigned for analytes of clinical interest. NIST SRM 2378 Fatty Acids in Frozen Human Serum was introduced in 2015 to help validate methods used for the analysis of FAs in serum, and consists of three different pools of serum acquired from (1) healthy donors who had taken fish oil dietary supplements (at least 1000mg per day) for at least one month (level 1 material), (2) healthy donors who had taken flaxseed oil dietary supplements (at least 1000mg per day) for at least one month (level 2 material), and (3) healthy donors eating "normal" diets who had not taken dietary supplements containing fish or plant oils (level 3 material). The use of dietary supplements by donors provided SRMs with natural endogenous ranges of FAs at concentrations observed in human populations. Results from analyses using two methods at NIST, including one involving a novel microwave-assisted acid hydrolysis procedure, and one at the CDC are presented here. These results and their respective uncertainties were combined to yield certified values with expanded uncertainties for 12 FAs and reference values with expanded uncertainties for an additional 18 FAs.

Effect of dietary n-3 polyunsaturated fatty acid rich fish oil on the endometrial prostaglandin production in the doe (Capra hircus)

Recently, we showed that dietary supplementation of n-3 PUFA rich fish oil (FO) decreased the metabolites of serum prostaglandin (PG) F2α and E2 during the window of pregnancy recognition in the doe. In this study, we investigated its effect on the changes on endometrial PG production in vitro. Cycling does (n = 12) of Rohilkhand region were divided into two equal groups and fed a concentrate diet supplemented with either FO containing 26% n-3 PUFA (TRT; n = 6) or palm oil (CON; n = 6) @ 0.6 mL/kg body weight for 57 days. Estrus was synchronized by two injections of PGF2α analogue viz, on day 25 and 36 of supplementation and laparo-hysterotomy was performed to obtain endometrial tissue on day 16 of the synchronized estrus. Endometrial explant culture was done using a defined medium.The basal PG production was assayed at 6 and 12 h. Endometrial explant was stimulated with oxytocin (OXT) and/or recombinant ovine interferon tau (roIFN-τ) and PGs were assayed at 3 and 12 h post-treatment. The relative expression of genes related to PG metabolism in the endometrium was done by Quantitative Real Time PCR technique (qRT-PCR). There was a significant (P < 0.05) decline in the basal production of PGF2α and PGE2 in the TRT as compared to the CON group. The cultured endometrial tissue produced PGF2α in a time- dependent fashion in both the groups (P < 0.05). Neither OXT nor roIFN-τ had a significant (P > 0.05) effect on the PGF2α and PGE2 production in the TRT group. Similarly, the PG production in the OXT and roIFN-τ was comparable with the control in TRT. Expression of mRNA for cyclooxygenase-2 (COX-2), cytosolic phospholipase A2 (cPLA2) and PGF synthase (PGFS) was lower (P < 0.05) whereas, PGE synthase and peroxisome proliferator-activated receptors such as PPAR-γ and δ was increased (P < 0.05) in n-3 PUFA fed doe. In conclusion, dietary supplementation of FO decreased the endometrial production of PGF2α and PGE2 by downregulating the COX-2, cPLA2 and PGFS transcripts in the doe. The findings suggest that n-3 PUFA influence embryo survival by modulating the endometrial PG.

Effect of dietary fish oil supplements alone or in combination with sunflower and linseed oil on ruminal lipid metabolism and bacterial populations in lactating cows

Fish oil (FO) alters ruminal biohydrogenation causing trans fatty acid (FA) intermediates to accumulate, but the effects of 18-carbon polyunsaturated FA supply on ruminal long-chain FA metabolism and microbial communities in cattle fed FO are not well established. Four cows fitted with rumen cannula were used in a 4 × 4 Latin square with 21-d experimental periods to evaluate the effects of FO alone or in combination with plant oils high in 18:2n-6 or 18:3n-3 on rumen microbial ecology and flow of FA at the omasum. Treatments comprised a basal grass silage-based diet containing no additional oil (control) or supplements of FO (200 g/d) or FO (200 g/d) plus 500 g/d of sunflower oil (SFO) or linseed oil (LFO). Flow of FA was determined using the omasal sampling technique. The relative abundance of key biohydrogenating bacteria was assessed by quantitative PCR on 16S rRNA genes in omasal digesta. Fish oil-supplemented treatments increased the amounts of trans-18:1, trans-18:2, and 20- to 22-carbon polyunsaturated FA escaping the rumen. Relative to the control, oil supplements had no effect on the amount of 18:0 leaving the rumen, but LFO decreased the flow of 18:0 at the omasum compared with SFO. Both SFO and LFO increased trans-18:1 relative to FO, whereas LFO resulted in the highest trans-18:2 and 20- to 22-carbon FA flow. Supplements of FO plus plant oils shifted biohydrogenation toward trans-10 18:1 formation. Compared with FO alone, the ruminal metabolism of 22:6n-3 in the rumen of lactating cows is more extensive on diets containing higher amounts of 18-carbon polyunsaturated FA. However, the biohydrogenation of 22:5n-3 was less extensive in LFO than SFO, but showed no difference between FO and diets containing plant oils. Ruminal outflow of 20:5n-3 was not altered when plant oils were added to FO. Alterations in the amount of intermediates at the omasum or ruminal biohydrogenation pathways were not accompanied by major changes in analyzed bacterial populations. In conclusion, dietary supplements of FO alone or in combination with plant oils increase the amount of biohydrogenation intermediates containing 1 or more trans double bonds escaping the rumen, which may have implications for host metabolism and the nutritional quality of ruminant foods.

Ozone-Induced Vascular Contractility and Pulmonary Injury Are Differentially Impacted by Diets Enriched With Coconut Oil, Fish Oil, and Olive Oil.

Fish, olive, and coconut oil dietary supplementation have several cardioprotective benefits, but it is not established if they protect against air pollution-induced adverse effects. We hypothesized that these dietary supplements would attenuate ozone-induced systemic and pulmonary effects. Male Wistar Kyoto rats were fed either a normal diet, or a diet supplemented with fish, olive, or coconut oil for 8 weeks. Animals were then exposed to air or ozone (0.8 ppm), 4 h/day for 2 days. Ozone exposure increased phenylephrine-induced aortic vasocontraction, which was completely abolished in rats fed the fish oil diet. Despite this cardioprotective effect, the fish oil diet increased baseline levels of bronchoalveolar lavage fluid (BALF) markers of lung injury and inflammation. Ozone-induced pulmonary injury/inflammation were comparable in rats on normal, coconut oil, and olive oil diets with altered expression of markers in animals fed the fish oil diet. Fish oil, regardless of exposure, led to enlarged, foamy macrophages in the BALF that coincided with decreased pulmonary mRNA expression of cholesterol transporters, cholesterol receptors, and nuclear receptors. Serum microRNA profile was assessed and demonstrated marked depletion of a variety of microRNAs in animals fed the fish oil diet, several of which were of splenic origin. No ozone-specific changes were noted. Collectively, these data indicate that although fish oil offered vascular protection from ozone exposure, it increased pulmonary injury/inflammation and impaired lipid transport mechanisms resulting in foamy macrophage accumulation, demonstrating the need to be cognizant of potential off-target pulmonary effects that might offset the overall benefit of this vasoprotective supplement.

Effect of Dietary Supplementation of Fish Oil on Nutrient Utilization, Haematology and Serum Metabolites of Captive Indian Leopards (Panthera pardus fusca)

This experiment was conducted to asses the effect of fish oil supplementation on nutrient utilization, haematology and serum metabolites of captive Indian leopards fed solely on buffalo meat on bone (BMB). Nine adult leopards (age 3–18 yrs; average BW 42.5 kg) were randomly distributed into 3 equal groups, in a replicated Latin square design. All the animals were fed normal zoo diet of BMB at 2.5 kg/d/animal for 6-d a week. The basal diets of the animals in three groups were supplemented with either 13 g of tallow (T1), 6.5 g of tallow and 6.5 g of fish oil (T2), or 13 g of fish oil (T3). Intake of nutrients was similar (P>0.05) among the groups. Digestibility of OM, CP and gross energy was higher (P<0.01) in groups T2 and T3. Serum concentrations of urea (P<0.001), total protein and globulins were higher and ratio of albumin: globulin was lower (P<0.05) in T2 and T3 as compared T1. However, serum total cholesterol was lower (P<0.05) in T3, only. Thus, it is concluded that supplementation of fish oil in captive Indian leopards would improve protein digestion and reduce serum cholesterol without affecting diet palatability, nutrient utilization and haematology.

Cardiovascular disease and omega-3s: Prescription products and fish oil dietary supplements are not the same

Despite achievement of optimal low-density lipoprotein cholesterol (LDL-C) control with statin therapy, patients with elevated triglycerides (TGs) and residual cardiovascular risk are commonly encountered in clinical practice. We present information from completed and ongoing clinical trials examining Rx omega-3s for TG-lowering and omega-3 dietary supplements to highlight important differences affecting patient management for nurse practitioners. Rx omega-3s demonstrate robust reductions in TGs and may have a role in reducing residual cardiovascular risk. Products containing docosahexaenoic acid (DHA) may raise LDL-C and should not be substituted for Rx eicosapentaenoic acid (EPA)-only icosapent ethyl, which does not raise LDL-C. Omega-3 dietary supplements (e.g., fish oils containing EPA and DHA) may be used for general health promotion; however, they are not regulated as medications and concerns regarding quality, purity, safety, and variability of content exist. It is important to advise patients that omega-3 dietary supplements are not medications and should not be substituted for Rx omega-3s. Large-scale cardiovascular outcomes studies are underway for Rx omega-3s in statin-treated patients. Nurse practitioners can take an active role in reducing residual cardiovascular risk and educating patients about important differences between Rx omega-3s and fish oil supplements.

Dietary Fish Oil Supplementation Enhances Expression of Genes Involved in Cornified Cell Envelope Formation in Rat Skin

Dietary Fish Oil Supplementation Enhances Expression of Genes Involved in Cornified Cell Envelope Formation in Rat Skin

Modulation of the gut microbiota by the mixture of fish oil and krill oil in high-fat diet-induced obesity mice.

Previous studies confirmed that dietary supplements of fish oil and krill oil can alleviate obesity in mice, but the underlying mechanism remains unclear. This study aims to discern whether oil treatment change the structure of the gut microbiota during the obesity alleviation. The ICR mice received high-fat diet (HFD) continuously for 12 weeks after two weeks of acclimatization with a standard chow diet, and the mice fed with a standard chow diet were used as the control. In the groups that received HFD with oil supplementation, the weight gains were attenuated and the liver index, total cholesterol, triglyceride and low-density lipoprotein cholesterol were reduced stepwise compared with the HFD group, and the overall structure of the gut microbiota, which was modulated in the HFD group, was shifted toward the structure found in the control group. Moreover, eighty-two altered operational taxonomic units responsive to oil treatment were identified and nineteen of them differing in one or more parameters associated with obesity. In conclusion, this study confirmed the effect of oil treatment on obesity alleviation, as well as on the microbiota structure alterations. We proposed that further researches are needed to elucidate the causal relationship between obesity alleviation and gut microbiota modulation.

Effects of dietary fish oil supplementation on performance, meat quality, and cecal fermentation of growing rabbits.

The objective of this study was to investigate the effect of dietary supplementation with fish oil on growth performance (during all fatening period), carcass characteristics and fatty acid (FA) profile of muscle and fat tissues (at slaughter), as well as cecal fermentation and ileal mucosa morphology of growing rabbits (at 30, 45, and 60 d of age). Two isonitrogenous and isoenergetic diets, only differing in their fat source, were formulated and provided each to 24 does (12 per diet) and their offspring during pregnancy and lactation. The control diet contained 4.59 g of n-3 per 100 g of total FA, and the enriched diet contained 14.9 g of n-3 per 100 g of total FA. From weaning (30 d of age) to slaughter (60 d), the litters (12 per diet; 8 kits each) continued fed the corresponding experimental diet. There were no differences ( > 0.05) between groups in ADFI, ADG and G:F ratio during the growing period. At slaughter, BW, full gastrointestinal tract weight, carcass yield, meat color and pH, drip loss percentage, content of scapular fat and tissue composition of the left hind leg were similar between groups ( > 0.05), but perirenal fat was lower ( = 0.020) and skin weight and abdominal fat tended to be lower ( = 0.055 and = 0.063, respectively) in enriched rabbits than in control ones. Total PUFA content in both LM and perirenal fat was greater ( = 0.021 and < 0.001, respectively) in enriched rabbits, that also showed lower n-6/n-3 ratios in LM (1.61 vs. 5.80; < 0.001) and perirenal fat (4.71 vs. 12.0; < 0.001) than those fed the control diet. Cecal concentrations of total VFA were greater ( < 0.001) in enriched than in control group at 30, 45 and 60 d of age, but diet did not affect ( ≥ 0.332) VFA profile, with the exception of a lower ( = 0.013) proportion of minor VFA (sum of isobutyrate, isovalerate, and valerate) in control group. Diet did not affect ( > 0.255) either pH and NH-N concentrations in the cecum or ileal morphology (crypt depth and villi length). The results showed that dietary fish oil supplementation enhanced beneficial long-chain n-3 FA and decreased n-6/n-3 ratio in rabbit meat and fat, being healthier for human consumption, without having negative effects on growth performance, cecal fermentation, and ileal morphology or carcass characteristics.

Fish Oil Supplementation Reduces Heart Levels of Interleukin-6 in Rats with Chronic Inflammation due to Epilepsy

Sudden unexpected death in epilepsy (SUDEP) is a major cause of premature death related to epilepsy. The causes of SUDEP remain unknown, but cardiac arrhythmias and asphyxia have been suggested as a major mechanism of this event. Inflammation has been implicated in the pathogenesis of both epilepsy and ventricular arrhythmia, with interleukin-6 (IL-6) being recognized as a crucial orchestrator of inflammatory states. Our group previously reported that levels of IL-6 were increased in the hearts of epileptic rats. In this scenario, anti-inflammatory actions are among the beneficial effects of fish oil dietary supplementation. This investigation revealed that elevated levels of IL-6 in the heart were markedly reduced in epileptic rats that were treated in the long-term with fish oil, suggesting protective anti-inflammatory actions against dangerously high levels of IL-6. Based on these findings, our results suggest beneficial effects of long-term intake of fish oil in reducing the inflammation associated with chronic epilepsy.

The future for long chain n-3 PUFA in the prevention of coronary heart disease: do we need to target non-fish-eaters?

Dietary guidelines in many countries include a recommendation to consume oily fish, mainly on the basis of evidence from prospective cohort studies that fish consumption is cardioprotective. However, average intakes are very low in a large proportion of the UK population. Some groups, such as vegans and vegetarians, purposely omit fish (along with meat) from their diet resulting in zero or trace intakes of long chain (LC) n-3 PUFA. Although the efficacy of dietary fish oil supplementation in the prevention of CVD has been questioned in recent years, the balance of evidence indicates that LC n-3 PUFA exert systemic pleiotropic effects through their influence on gene expression, cell signalling, membrane fluidity and by conversion to specialised proresolving mediators; autacoid lipid mediators that resolve inflammatory events. The long-term impact of reduced tissue LC n-3 PUFA content on cardiovascular health is surprisingly poorly understood, particularly with regard to how low proportions of LC n-3 PUFA in cell membranes may affect cardiac electrophysiology and chronic inflammation. Randomised controlled trials investigating effects of supplementation on prevention of CHD in populations with low basal LC n-3 PUFA tissue status are lacking, and so the clinical benefits of supplementing non-fish-eating groups with vegetarian sources of LC n-3 PUFA remain to be determined. Refocusing dietary LC n-3 PUFA intervention studies towards those individuals with a low LC n-3 PUFA tissue status may go some way towards reconciling results from randomised controlled trials with the epidemiological evidence.

Repetitive and Prolonged Omega-3 Fatty Acid Treatment after Traumatic Brain Injury Enhances Long-Term Tissue Restoration and Cognitive Recovery

Traumatic brain injury (TBI) is one of the most disabling clinical conditions that could lead to neurocognitive disorders in survivors. Our group and others previously reported that prophylactic enrichment of dietary omega-3 polyunsaturated fatty acids (n-3 PUFAs) markedly ameliorate cognitive deficits after TBI. However, it remains unclear whether a clinically relevant therapeutic regimen with n-3 PUFAs administered after TBI would still offer significant improvement of long-term cognitive recovery. In the present study, we employed the decline of spatial cognitive function as a main outcome after TBI to investigate the therapeutic efficacy of post-TBI n-3 PUFA treatment and the underlying mechanisms. Mice were subjected to sham operation or controlled cortical impact, followed by random assignment to receive the following four treatments: (1) vehicle control; (2) daily intraperitoneal injections of n-3 PUFAs for 2 weeks, beginning 2 h after TBI; (3) fish oil dietary supplementation throughout the study, beginning 1 day after TBI; or (4) combination of treatments (2) and (3). Spatial cognitive deficits and chronic brain tissue loss, as well as endogenous brain repair processes such as neurogenesis, angiogenesis, and oligodendrogenesis, were evaluated up to 35 days after TBI. The results revealed prominent spatial cognitive deficits and massive tissue loss caused by TBI. Among all mice receiving post-TBI n-3 PUFA treatments, the combined treatment of fish oil dietary supplement and n-3 PUFA injections demonstrated a reproducible beneficial effect in attenuating cognitive deficits although without reducing gross tissue loss. Mechanistically, the combined treatment promoted post-TBI restorative processes in the brain, including generation of immature neurons, microvessels, and oligodendrocytes, each of which was significantly correlated with the improved cognitive recovery. These results indicated that repetitive and prolonged n-3 PUFA treatments after TBI are capable of enhancing brain remodeling and could be developed as a potential therapy to treat TBI victims in the clinic.

Fish Oil Dietary Supplement Modifies Inhaled Ozone‐Induced Vascular and Pulmonary Effects

The omega‐3 polyunsaturated fatty acids present in fish oil supplements are proposed to offer cardioprotective benefits, but it is not established if these supplements can protect against the adverse health effects induced by exposure to air pollution. Ozone, an ubiquitous air pollutant and a component of smog, is associated with premature cardiovascular mortality. We hypothesized that fish oil dietary supplementation would attenuate ozone‐induced vascular and pulmonary impairments. Male Wistar Kyoto (WKY) rats were fed either a normal diet or a diet enriched with fish oil (6% by weight) starting at 4 weeks of age. Eight weeks following the initial start of the diet, animals were exposed to filtered air or 0.8 ppm ozone, 4h/day for 2 days. Aortic segments were isolated for myograph assessment of vascular reactivity in response to pharmacological intervention. The phenylephrine‐induced vasoconstriction that was increased following ozone exposure in the animals fed the normal diet was completely abolished in the animals fed the fish oil diet, demonstrating vascular protection against this ozone‐induced effect. Contrary to the vasoprotective response, the fish oil supplementation exacerbated pulmonary injury and inflammation. The fish oil diet increased baseline levels of bronchoalveolar lavage fluid (BALF) total protein, inflammatory cells (macrophages, neutrophils, and eosinophils), inflammatory cytokines (TNF‐α and KC/GRO), as well as, lactate dehydrogenase, gamma‐glutamyl transpeptidase, and n‐acetyl glucosaminidase (NAG) activity, but did not increase albumin leakage. Fish oil further exacerbated increases in NAG activity, TNF‐α and IL‐6 proteins following ozone exposure, but attenuated the ozone‐induced albumin leakage, neutrophilic and eosinophilic inflammation. Furthermore, fish oil supplementation regardless of exposure led to enlarged, foamy macrophages in the BALF that coincided with decreased mRNA expression of cholesterol transporters (ABCA1 and ABCG1), cholesterol receptors (SR‐B1 and LDLR), and nuclear receptors (LXR‐α and PPAR‐α) in the lung. Collectively, these data indicate that while fish oil offered protection from ozone‐induced aortic vasoconstriction and vascular albumin leakage in the lung, it increased pulmonary injury/inflammation and impaired lipid transport mechanisms resulting in foamy macrophage accumulation. These data demonstrate the need to be cognizant of potential off‐target pulmonary effects that might offset the overall benefit of this vasoprotective dietary supplement. (Does not reflect the US EPA policy).Support or Funding InformationThis work was supported by US EPA funds.

Anti-cancer Mechanism of Docosahexaenoic Acid in Pancreatic Carcinogenesis: A Mini-review.

Pancreatic cancer is a highly aggressive malignant tumor of the digestive system and radical resection, which is available to very few patients, might be the only possibility for cure. Since therapeutic choices are limited at the advanced stage, prevention is more important for reducing incidence in high-risk individuals with family history of pancreatic cancer. Epidemiological studies have shown that a high consumption of fish oil or ω3-polyunsaturated fatty acids reduces the risk of pancreatic cancers. Dietary fish oil supplementation has shown to suppress pancreatic cancer development in animal models. Previous experimental studies revealed that several hallmarks of cancer involved in the pathogenesis of pancreatic cancer, such as the resistance to apoptosis, hyper-proliferation with abnormal Wnt/β-catenin signaling, expression of pro-angiogenic growth factors, and invasion. Docosahexaenoic acid (DHA) is a ω3-polyunsaturated fatty acid and rich in cold oceanic fish oil. DHA shows anti-cancer activity by inducing oxidative stress and apoptosis, inhibiting Wnt/β-catenin signaling, and decreasing extracellular matrix degradation and expression of pro-angiogenic factors in pancreatic cancer cells. This review will summarize anti-cancer mechanism of DHA in pancreatic carcinogenesis based on the recent studies.

Supplementing oregano essential oil to boar diet with strengthened fish oil: Effects on semen antioxidant status and semen quality parameters.

Previous research has shown benefits of dietary fish oil supplementation on semen quality of boars. However, little is known about how antioxidant protects lipid peroxidation on spermatozoa from n-3 polyunsaturated fatty acid (PUFA) addition. This study evaluated the effect of oregano essential oil (OEO) supplementation on semen antioxidant status and semen quality in boars fed a diet enriched with fish oil. Thirty-four mature boars of proven fertility, received daily 2.5kg basal diet top-dressed with 45g soybean oil and 15g fish oil to meet the n-3 PUFA requirement of spermatozoa, randomly allocated to one of four groups supplemented with 100mg α-tocopheryl acetate kg-1 (control), or 250 or 500 or 750mg OEO kg-1 for 16weeks. Semen was collected at weeks 0, 8, 12 and 16 for measurements of sperm production, motion characteristics, sperm α-tocopherol content, antioxidant enzyme activities, reactive oxygen species (ROS), DNA damage (8-hydroxydeoxyguanosine, 8-OHdG), lipoperoxidation (malondialdehyde, MDA) and seminal total antioxidant capacity (TAC). Sperm production and motion characteristics were similar (p>.05) among groups throughout the experimental week 16, but increased (p<.01) with experimental week. Although higher α-tocopherol content and superoxide dismutase (SOD) activities were in OEO group spermatozoa, feeding diet with 500mg/kg OEO resulted in elevation in seminal TAC, decrease in sperm ROS, MDA and 8-OHdG than control group (p<.05). Overall, these results support the view that oregano essential oil has a positive effect on antioxidant capacity in boar when used fish oil.

Effects of dietary fish oil supplementation on performance, meat quality, and cecal fermentation of growing rabbits

Effects of dietary fish oil supplementation on performance, meat quality, and cecal fermentation of growing rabbits

Omega-3 fatty acid fish oil dietary supplements contain saturated fats and oxidized lipids that may interfere with their intended biological benefits

Widely available fish oil dietary supplements (DS) may contain fats and oxidized lipids in addition to the beneficial omega-3 fatty acids (OM3FAs) for which they are purchased. Little is known about the potential biological effects of these oxidized lipids. The objective of this study was to assess the fatty acid content, oxidation products, and biological effects of leading fish oil DS available in the United States. Three top-selling fish oil DS in the US were included in this analysis. Fatty acid composition was measured using gas chromatography. Lipid oxidation (primary and secondary products) was measured by spectroscopy in both DS and a prescription OM3FA product. OM3FAs were also isolated and concentrated from DS and were tested for the ability to inhibit copper-induced oxidation of human small dense low-density lipoprotein particles (sdLDL) in vitro. Fish oil DS were found to contain more than 30 different fatty acids, including 10 to 14 different saturated species comprising up to 36% of the total fatty acid content. Levels of OM3FAs also varied widely among DS (33%–79%). Primary (peroxide), secondary (anisidine), and total oxidation products exceeded maximum levels established by international standards of quality in the DS but not the prescription OM3FA product. Oxidation of sdLDL was inhibited by >95% (P < 0.001) with non-oxidized forms of OM3FA but not with OM3FAs isolated from DS, which were a mixture of oxidized and non-oxidized OM3FAs. These data indicate that levels of saturated fat and oxidized OM3FAs found in common DS may interfere with their intended/potential biological benefits.

A Post-stroke Therapeutic Regimen with Omega-3 Polyunsaturated Fatty Acids that Promotes White Matter Integrity and Beneficial Microglial Responses after Cerebral Ischemia.

White matter injury induced by ischemic stroke elicits sensorimotor impairments, which can be further deteriorated by persistent proinflammatory responses. We previously reported that delayed and repeated treatments with omega-3 polyunsaturated fatty acids (n-3 PUFAs) improve spatial cognitive functions and hippocampal integrity after ischemic stroke. In the present study, we report a post-stroke n-3 PUFA therapeutic regimen that not only confers protection against neuronal loss in the gray matter but also promotes white matter integrity. Beginning 2h after 60min of middle cerebral artery occlusion (MCAO), mice were randomly assigned to receive intraperitoneal docosahexaenoic acid (DHA) injections (10mg/kg, daily for 14days), alone or in combination with dietary fish oil (FO) supplements starting 5days after MCAO. Sensorimotor functions, gray and white matter injury, and microglial responses were examined up to 28days after MCAO. Our results showed that DHA and FO combined treatment-facilitated long-term sensorimotor recovery and demonstrated greater beneficial effect than DHA injections alone. Mechanistically, n-3 PUFAs not only offered direct protection on white matter components, such as oligodendrocytes, but also potentiated microglial M2 polarization, which may be important for white matter repair. Notably, the improved white matter integrity and increased M2 microglia were strongly linked to the mitigation of sensorimotor deficits after stroke upon n-3 PUFA treatments. Together, our results suggest that post-stroke DHA injections in combination with FO dietary supplement benefit white matter restoration and microglial responses, thereby dictating long-term functional improvements.

Effects of extruded linseed and level and type of starchy concentrate in a diet containing fish oil on dairy goat performance and milk fatty acid composition

Based on the potential benefits for long-term human health, nutritional strategies have been developed in order to increase the milk fat concentrations of bioactive fatty acids (FA) in ruminants. Dietary supplements of fish oil (FO), extruded linseed (EL) or a mixture of EL and FO increase c9,t11-CLA and n-3 PUFA in milk from bovine and caprine. These supplements associated with a high level of starch from concentrates cause milk fat depression in cows, but information for dairy goats is limited. An experiment was performed to investigate the effects of addition of extruded linseed to a diet containing fish oil in interaction with the type and level of starch concentrate on dairy goat performance and milk fatty acid (FA) profile. Following a 2×3 factorial design, 72 goats were allocated to 6 experimental diets based on alfalfa hay and with concentrates including fish oil (40g/d) without or with extruded linseed (360g/d) and either rich in starch from barley grain or extruded wheat or that were low in starch from barley grain. In contrast to cows, in goats adding extruded linseed to low-or high-starch diets based on hay and containing fish oil increases milk fat content and changes the milk FA composition in particular by increasing some bioactive FA with 18 carbons. In these conditions FA changes were characterized by decreases in SFA (on average 22% decrease) and increases in 18:0, c9-18:1, t11-18:1, c9,t11-CLA and 18:3n-3. The milk t10-18:1 concentration remained low (<1% total FA) and the t11-18:1/t10-18:1 ratio was much higher than in cows fed fish oil with plant oils. The combination of EL and FO induced larger concentrations in t11-18:1 and c9,t11-CLA than FO alone (2.9- and 2.1-fold higher, respectively). The apparent transfer rates of 20:5n-3 and 22:6n-3 from fish oil to milk were lower when EL was added to the diet (on average, 6.6 and 5.4%) compared to FO alone (on average, 8.0 and 7.4%, respectively). Extruded wheat, as the more rapidly degradable starch source in the rumen, decreased milk fat content. Based on the milk FA changes (e.g., c9,t11-CLA,18:2n-6, 18:3n-3, 20:5n-3, 22:6n-3), diets rich in starch from barley grain would induce a lower rumen bacterial biomass and a more extensive biohydrogenation of dietary FA in the rumen than diets rich in starch from extruded wheat. Starch level in the diets had negative effect on milk yield but moderate effects on milk fat and FA content, under these dietary conditions.