Effects of short-term infusion of lipid emulsions on pro-inflammatory cytokines and lymphocyte apoptosis in septic and non-septic rats

Long-term administration of PUFA is known to modulate immune functions and apoptotic pathways depending on the respective amount of n-6 and n-3 fatty acids (FA). Data on short-term effects on apoptotic pathways are rare. Apoptosis of splenic lymphocytes is the hallmark of detrimental sepsis. Therefore, we aimed to compare the immediate effects of parenterally administered n-6-enriched soyabean oil (SO)- and n-3-enriched fish oil (FO)-based lipid emulsions after laparotomy (LAP; sham procedure) and after induction of acute, severe sepsis by caecal ligation and incision. After 390?min of observation time, plasma was analysed for IL-1β, IL-6 and NEFA. Apoptosis in splenic lymphocytes was quantified by Annexin-V expression. After LAP, infusion of both FO and SO did not change cytokine concentrations. Sepsis increased both cytokines. FO but not SO further augmented the rise. After LAP, SO increased NEFA, and both lipid emulsions reduced free arachidonic acid (AA). Sepsis resulted in a dramatic decrease in NEFA and AA. The drop in NEFA and AA was prevented by both SO and FO. In addition, FO resulted in an increased concentration of n-3 FA under both conditions. Infusion of both lipid emulsions induced apoptosis in splenic lymphocytes after LAP. Sepsis-induced apoptosis was not further enhanced by FO or SO. The present study shows that short-term administration of FO as opposed to SO caused pro-inflammatory effects during sepsis. Moreover, short-term administration of both SO and FO suffices to induce apoptosis in splenic lymphocytes. Finally, SO and FO do not further enhance sepsis-induced splenic apoptosis.     

Use of Lipids in Neonates Requiring Parenteral Nutrition

Neonates have limited antioxidative capacity and are at increased risk of infection and inflammation—a situation that is exacerbated in preterm neonates. Together, oxidative stress and inflammation are implicated in many serious conditions affecting neonates, such as bronchopulmonary dysplasia and periventricular leukomalacia. Neonates requiring parenteral nutrition have certain nutritional requirements. For example, very long-chain ω-3 polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are regarded as conditionally essential with critical roles during early retinal and brain development, and may also have other benefits such as anti-inflammatory effects. Because of these factors, the choice of lipid emulsion used as part of parenteral nutrition support may influence clinical outcomes in neonates. There are concerns that lipid emulsions based purely on soybean oil may increase lipid peroxidation, oxidative stress, and inflammation because of their high ω-6 PUFA and low ω-3 PUFA concentrations. Composite fish-oil containing lipid emulsions may provide advantages for neonates owing to their high DHA and EPA content and high antioxidant (α-tocopherol) levels. Here, we discuss clinical trials of lipid emulsions in preterm and term neonatal populations, with a particular emphasis on markers of oxidative stress and DHA and EPA levels. Olive oil/soybean oil lipid emulsions have shown few advantages in neonates over other lipid emulsions. However, compared with either pure soybean or soybean/olive-oil based emulsions, composite fish-oil containing lipid emulsions reduce oxidative stress/lipid peroxidation and also increase DHA and EPA levels. These advantages may translate into clinical benefits for neonates requiring parenteral nutrition.     

DHA-Enriched Fish Oil Ameliorates Deficits in Cognition Associated with Menopause and the APOE4 Genotype in Rodents

Female APOE4 carriers have a greater predisposition to developing Alzheimer’s disease (AD) compared to their male counterparts, which may partly be attributed to menopause. We previously reported that a combination of menopause and APOE4 led to an exacerbation of cognitive and neurological deficits, which were associated with reduced brain DHA and DHA:AA ratio. Here, we explored whether DHA-enriched fish oil (FO) supplementation mitigated the detrimental impact of these risk factors. Whilst DHA-enriched fish oil improved recognition memory (NOR) in APOE4 VCD (4-vinylcyclohexene diepoxide)-treated mice (p < 0.05), no change in spatial working memory (Y-maze) was observed. FO supplementation increased brain DHA and nervonic acid and the DHA:AA ratio. The response of key bioenergetic and blood–brain barrier related genes and proteins provided mechanistic insights into these behavioural findings, with increased BDNF protein concentration as well as mitigation of aberrant Erβ, Cldn1 and Glut-5 expression in APOE4 mice receiving fish oil supplementation (p < 0.05). In conclusion, supplementation with a physiologically relevant dose of DHA-enriched fish oil appears to offer protection against the detrimental effects of menopause, particularly in “at-risk” APOE4 female carriers.     

Rise in DPA Following SDA-Rich Dietary Echium Oil Less Effective in Affording Anti-Arrhythmic Actions Compared to High DHA Levels Achieved with Fish Oil in Sprague-Dawley Rats

Stearidonic acid (SDA; C18:4n-3) has been suggested as an alternative to fish oil (FO) for delivering health benefits of C ≥ 20 long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA). Echium oil (EO) represents a non-genetically-modified source of SDA available commercially. This study compared EO and FO in relation to alterations in plasma and tissue fatty acids, and for their ability to afford protection against ischemia-induced cardiac arrhythmia and ventricular fibrillation (VF). Rats were fed (12 weeks) diets supplemented with either EO or FO at three dose levels (1, 3 and 5% w/w; n = 18 per group). EO failed to influence C22:6n-3 (DHA) but increased C22:5n-3 (DPA) in tissues dose-dependently, especially in heart tissue. Conversely, DHA in hearts of FO rats showed dose-related elevation; 14.8%–24.1% of total fatty acids. Kidney showed resistance for incorporation of LC n-3 PUFA. Overall, FO provided greater cardioprotection than EO. At the highest dose level, FO rats displayed lower (p < 0.05) episodes of VF% (29% vs. 73%) and duration (22.7 ± 12.0 vs. 75.8 ± 17.1 s) than the EO group but at 3% EO was comparable to FO. We conclude that there is no endogenous conversion of SDA to DHA, and that DPA may be associated with limited cardiac benefit.     

Benefits of Structured and Free Monoacylglycerols to Deliver Eicosapentaenoic (EPA) in a Model of Lipid Malabsorption

In the present study, we used a preclinical model of induced lipolytic enzyme insufficiency, and hypothesized that the use of monoacylglycerols (MAG) will enhance their bioavailability and delivery to the tissues. Experimental diets containing 20% lipids were fed to rats for 21 days with or without Orlistat. The control diet of fish oil (FO), a source of EPA and DHA, was tested against: structured (A) vanillin acetal of sn-2 MAG (Vanil + O) and (B) diacetyl derivative of sn-2 MAG (Acetyl + O) and (C) free MAG (MAG + O). FA profiles with an emphasis on EPA and DHA levels were determined in plasma, red blood cells (RBC), liver, spleen, brain and retina. We observed significant reduction of lipid absorption when rats co-consumed Orlistat. As expected, the FO groups with and without Orlistat showed the biggest difference. The Vanil + O, Acetyl + O and MAG + O groups, demonstrated higher levels of EPA (5.5 ± 1.9, 4.6 ± 1.6 and 5.6 ± 0.6, respectively) in RBC compared with FO + O diets (3.3 ± 0.2, 2.6 ± 0.2). Levels of EPA incorporation, in plasma, were similar to those obtained for RBC, and similar trends were observed for the collected tissues and even with DHA levels. These observations with two MAG derivatives providing the fatty acid esterified in the sn-2 position, show that these molecules are efficient vehicles of EPA in malabsorption conditions which is in line with our hypothesis. Free MAG, characterized as having exclusively sn-1(3) isomers of EPA, demonstrated better absorption efficiencies and accretion to tissues when compared to structured MAG. The study demonstrated that structured and free MAG can be used efficiently as an enteral vehicle to supply bioactive fatty acids such as EPA and DHA in lipid malabsorption where diminished lipolytic activity is the underlying cause.     

Echium Oil Reduces Plasma Triglycerides by Increasing Intravascular Lipolysis in apoB100-Only Low Density Lipoprotein (LDL) Receptor Knockout Mice

Echium oil (EO), which is enriched in SDA (18:4 n-3), reduces plasma triglyceride (TG) concentrations in humans and mice. We compared mechanisms by which EO and fish oil (FO) reduce plasma TG concentrations in mildly hypertriglyceridemic male apoB100-only LDLrKO mice. Mice were fed one of three atherogenic diets containing 0.2% cholesterol and palm oil (PO; 20%), EO (10% EO + 10% PO), or FO (10% FO + 10% PO). Livers from PO- and EO-fed mice had similar TG and cholesteryl ester (CE) content, which was significantly higher than in FO-fed mice. Plasma TG secretion was reduced in FO vs. EO-fed mice. Plasma very low density lipoprotein (VLDL) particle size was ordered: PO (63 ± 4 nm) > EO (55 ± 3 nm) > FO (40 ± 2 nm). Post-heparin lipolytic activity was similar among groups, but TG hydrolysis by purified lipoprotein lipase was significantly greater for EO and FO VLDL compared to PO VLDL. Removal of VLDL tracer from plasma was marginally faster in EO vs. PO fed mice. Our results suggest that EO reduces plasma TG primarily through increased intravascular lipolysis of TG and VLDL clearance. Finally, EO may substitute for FO to reduce plasma TG concentrations, but not hepatic steatosis in this mouse model.     

A Food-Based Intervention in a Military Dining Facility Improves Blood Fatty Acid Profile

Enhancing dietary omega-3 highly unsaturated fatty acids (n-3 HUFA) intake may confer neuroprotection, brain resiliency, improve wound healing and promote cardiovascular health. This study determined the efficacy of substituting a few common foods (chicken meat, chicken sausage, eggs, salad dressings, pasta sauces, cooking oil, mayonnaise, and peanut butter) lower in omega-6 polyunsaturated fatty acids (n-6 PUFA) and higher in n-3 HUFA in a dining facility on blood fatty acid profile. An eight-week prospective, between-subjects (n = 77), repeated measures, parallel-arm trial was conducted. Participants self-selected foods consumed from conventionally produced foods (control), or those lower n-6 PUFA and higher n-3 HUFA versions (intervention). Changes in blood omega-3 index, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), n-6 PUFA, lipid profile, and food satisfaction were main outcomes. Between-group differences over time were assessed using a linear mixed model to measure the effect of diet on blood serum fatty acids and inflammatory markers. The intervention group achieved a higher omega-3 index score (3.66 ± 0.71 vs. 2.95 ± 0.77; p < 0.05), lower total n-6 (10.1 ± 4.6 vs. 15.3 ± 6.7 µg/mL; p < 0.05), and higher serum concentration of EPA (5.0 ± 1.31 vs. 4.05 ± 1.56 µg/mL; p < 0.05) vs. controls. Satisfaction in intervention foods improved or remained consistent. Substitution of commonly eaten dining facility foods with like-items higher in DHA and EPA and lower in n-6 PUFA can favorably impact fatty acid status and the omega-3 index.     

Linseed,Baru, and Coconut Oils: NMR-Based Metabolomics,Leukocyte Infiltration Potential In Vivo,and Their Oil Characterization. Are There Still Controversies?

Different fatty acid proportions produce potential inflammatory and metabolic changes in organisms. However, the evidence for how each fatty acid mediates the metabolic pathway, and its lipid stability remains controversial. To resolve this controversy, the present study investigated the metabolic effects of cold-pressed linseed (LG), coconut (CG), and baru (BG) oils in comparison to those of soybean oil (SG) in mice, in terms of their oil characterization and stability. The quality analysis showed less oxidative behavior among PUFA-rich oils (SO, BO, and LO, with induction periods lower than 2 h compared to 39.8 h for CG), besides the high contents of tocopherols and carotenoids in SG and LG. In the experimental study, CG presented higher triglyceride (257.93 ± 72.30) and VLDL-cholesterol levels (51.59 ± 14.46, p < 0.05), while LG reduced LDL levels (59.29 ± 7.56, p < 0.05) when compared to SG (183.14 ± 22.06, 36.63 ± 4.41 and 131.63 ± 29.0, respectively). For visceral fats, the adiposity index was lower for BG (7.32 ± 3.13) and CG (9.58 ± 1.02, p < 0.05) in relation to SG (12.53 ± 2.80), and for leukocyte recruitment, CG presented lower polymorphonuclear (PMN) (p < 0.0001) and mononuclear (MN) (p < 0.05) cell infiltration, demonstrating anti-inflammatory potential. In NMR-based metabolomics, although CG presented higher values for the glucose, lactate, and LDL/VLDL ratio, this group also evidenced high levels of choline, a lipotropic metabolite. Our study emphasized the controversies of saturated fatty acids, which impair serum lipids, while alfa-linolenic acid presented cardioprotective effects. However, coconut oil also has a positive immunomodulatory pathway and was found to reduce visceral bodyfat in mice. Therefore, for future applications, we suggest a combination of lauric and al-fa-linolenic acid sources, which are present in coconut and linseed oil, respectively. This combination could be less obesogenic and inflammatory and exert cardioprotective action.     

Adaptation of lipid metabolism, tissue composition and flesh quality in gilthead sea bream (Sparus aurata) to the replacement of dietary fish oil by linseed and soyabean oils

Linseed (LO) and soyabean (SO) oils were evaluated as fish-oil (FO) substitutes in the diets of marketable-sized gilthead sea bream (Sparus aurata). Practical diets were designed factorially with the lipid added as follows (%): FO 100, LO 60+FO 40, LO 80+FO 20, SO 60+FO 40, SO 80+FO 20. The effects of experimental diets on growth, fatty acids patterns in liver and muscle, flesh quality variables and activities of selected enzymes involved in lipid synthesis and catabolism were determined at the end of a 7-month trial. Fatty acid composition of liver and muscle generally reflected the fatty acid composition of the diets. The n-3 PUFA levels were significantly reduced by the inclusion of vegetable oils. This tendency was more pronounced for EPA than for docosahexaenoic acid. The n-3:n-6 fatty acid ratio reached the lowest values in fish fed the SO diets; this was associated with a higher liver lipid deposition. No differences were found in fillet texture and pH. However, under conditions of forced peroxidation, muscles from fish fed the SO diets had lower peroxidation levels. Vegetable oil substitution decreased lipogenesis in liver and this effect was greatest at the highest substitution level. In contrast, muscle beta-oxidation enzymes had increased activities with vegetable oil substitution. Thus, the lower hepatic lipogenesis was correlated with an increased lipid utilisation in muscle. It is concluded that growth and lipid metabolism were affected by experimental diets.     

Administration of an Intravenous Fat Emulsion Enriched with Medium-Chain Triglyceride/ω-3 Fatty Acids is Beneficial Towards Anti-Inflammatory Related Fatty Acid Profile in Preterm Neonates: A Randomized,Double-Blind Clinical Trial

Intravenous administration of pure soybean oil emulsions high in linoleic acid may lead to inflammation and lipid peroxidation in preterm neonates. We aimed to investigate the effects of a medium-chain triglyceride (MCT)/ω-3 polyunsaturated fatty acid (PUFA)-enriched intravenous fat emulsion (IVFE) on plasma fatty acid (FA) profile and serum interleukin-6 (IL-6) in preterm neonates. In this double-blind randomized study, 92 preterm neonates (gestational age < 32 weeks, birth weight < 1500 g) were assigned to receive either MCT/ω-3 PUFA-enriched IVFE (Intervention Group) or soybean oil-based IVFE (Control Group). Levels of FAs were measured at baseline (day 0) and day 15 of parenteral nutrition with gas-chromatography mass-spectrometry. Serum IL-6 was measured with sandwich ELISA in 59 neonates. Plasma FAs changed significantly over time; the MCT/ω-3 PUFA-IVFE group showed higher ω-3 PUFAs (p = 0.031), eicosapentaenoic acid (p = 0.000), and oleic acid (p = 0.003), and lower ω-6/ω-3 PUFAs ratio (p = 0.001) and ω-6 PUFAs (p = 0.023) compared to control group. Linoleic acid was higher in the soybean oil (SO)-based IVFE arm compared to the MCT/ω-3 PUFAs-IVFE arm (p = 0.006). Both fat emulsion types decreased IL-6 compared to baseline, but changes were insignificant between groups. Administration of MCT/ω-3 PUFA-enriched IVFE in preterm neonates is beneficial in changing the FA profile consistent with attenuated inflammatory response.     

Vitamin E content in fish oil emulsion does not prevent lipoperoxidative effects on human colorectal tumors

ObjectiveThe anticancer action exerted by polyunsaturated fatty acid peroxidation may not be reproduced by commercially available lipid emulsions rich in vitamin E. Therefore, we evaluated the effects of fish oil (FO) emulsion containing α-tocopherol 0.19 g/L on human colorectal adenocarcinoma cells and tumors.MethodsHT-29 cell growth, survival, apoptosis, and lipid peroxidation were analyzed after a 24-h incubation with FO 18 to 80 mg/L. Soybean oil (SO) emulsion was used as an isocaloric and isolipidic control. In vivo, nude mice bearing HT-29 tumors were sacrificed 7 d after an 11-d treatment with intravenous injections of FO or SO 0.2 g ? kg^?1 ? d^?1 FO or SO to evaluate tumor growth, necrosis, and lipid peroxidation.ResultsThe FO inhibited cell viability and clonogenicity in a dose-dependent manner, whereas SO showed no significant effect compared with untreated controls. Lipid peroxidation and cell apoptosis after treatment with FO 45 mg/L were increased 2.0-fold (P < 0.01) and 1.6-fold (P = 0.04), respectively. In vivo, FO treatment did not significantly affect tumor growth. However, immunohistochemical analyses of tumor tissue sections showed a decrease of 0.6-fold (P < 0.01) in the cell proliferation marker Ki-67 and an increase of 2.3-fold (P = 0.03) in the necrotic area, whereas malondialdehyde and total peroxides were increased by 1.9-fold (P = 0.09) and 7.0-fold (P < 0.01), respectively, in tumors of FO-treated compared with untreated mice.ConclusionThese results suggest that FO but not SO has an antitumor effect that can be correlated with lipid peroxidation, despite its vitamin E content.     

Effect of sex and genotype on cardiovascular biomarker response to fish oils: the FINGEN Study

BACKGROUND: The lipid-modulatory effects of high intakes of the fish-oil fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are well established and likely to contribute to cardioprotective benefits. OBJECTIVES: We aimed to determine the effect of moderate EPA and DHA intakes (<2 g EPA+DHA/d) on the plasma fatty acid profile, lipid and apolipoprotein concentrations, lipoprotein subclass distribution, and markers of oxidative status. We also aimed to examine the effect of age, sex, and apolipoprotein E (APOE) genotype on the observed responses. DESIGN: Three hundred twelve adults aged 20-70 y, who were prospectively recruited according to age, sex, and APOE genotype, completed a double-blind placebo-controlled crossover study. Participants consumed control oil, 0.7 g EPA+DHA/d (0.7FO), and 1.8 g EPA+DHA/d (1.8FO) capsules in random order, each for an 8-wk intervention period, separated by 12-wk washout periods. RESULTS: In the group as a whole, 8% and 11% lower plasma triacylglycerol concentrations were evident after 0.7FO and 1.8FO, respectively (P < 0.001): significant sex x treatment (P = 0.038) and sex x genotype x treatment (P = 0.032) interactions were observed, and the greatest triacylglycerol-lowering responses (reductions of 15% and 23% after 0.7FO and 1.8FO, respectively) were evident in APOE4 men. Furthermore, lower VLDL-cholesterol (P = 0.026) and higher LDL-cholesterol (P = 0.010), HDL-cholesterol (P < 0.001), and HDL2 (P < 0.001) concentrations were evident after fish-oil intervention. CONCLUSIONS: Supplements providing EPA+DHA at doses as low as 0.7 g/d have a significant effect on the plasma lipid profile. The results of the current trial, which used a prospective recruitment approach to examine the responses in population subgroups, are indicative of a greater triacylglycerol-lowering action of long-chain n-3 polyunsaturated fatty acids in males than in females.     

A Novel Approach to Improving Fat Delivery in Neonatal Enteral Feeding

Continuous infusion systems used for enteral nutrition support in the neonatal intensive care unit deliver as little as 60% of the fat in human milk to the neonate. This study determined the effect of mixing common feedings for preterm infants in the feeding bag and tubing on fat losses during enteral feeding. Laboratory models were developed to assess the contribution of various mixing techniques to delivered fat content. Fat content was measured periodically during feeding and compared to baseline measurements. A multistage approach incorporating a feeding bag inverter and a tubing circulation loop delivered >90% of milk fat when used in conjunction with a commercial continuous infusion system. With unfortified human milk, this approach delivered 91.9% ± 1.5% of fat content over a one hour feed, significantly greater (p < 0.01) than 77.5% ± 2.2% delivered by continuous infusion controls (Mean ± SEM). With fortified human milk, this approach delivered 92.1% ± 2.4% of fat content, significantly greater (p < 0.01) than 79.4% ± 1.0% delivered by a non-adapted infusion system (Mean ± SEM). Mixing human milk during continuous infusion improves fat delivery, which may improve nutrition and growth outcomes in low birth weight neonates.     

Manipulation of tissue fatty acid profile by intravenous lipids in dogs

This study was undertaken to determine the effects on the fatty acid (FA) composition of various dog tissues of 4 different lipid emulsions (a 100% long-chain triacylglycerol (LCT) derived from soya bean oil emulsion, a mixed 50% medium-chain triacylglycerol (MCT)/50% LCT emulsion as well as both these emulsions supplemented with 10% fish oil (FO) triacylglycerols), when daily infused over 15 days as a substantial component of total parenteral nutrition. Lipids represented 55% of the non-protein energy. Blood samples as well as biopsies from liver, muscle and adipose tissue were taken 15 days before, and again immediately after TPN. In addition, the spleen was also removed immediately after TPN. Tissue FA composition was analysed by gas liquid chromatography of each lipid component after separation by thin layer chromatography. No differences in either safety or tolerance were detected between the different TPN preparations. In particular, infusion over 2 weeks of fat emulsions containing 10% fish oil was tolerated as well as conventional LCT and MCT/LCT emulsions. Relative linoleate content of tissue triacylglycerol (TG) was markedly increased in animals that received the LCT emulsions (e.g. from 22.6 +/- 2.5% to 32.2 +/- 0.6% in the liver), this effect being markedly reduced with MCT/LCT preparations. n-3FA were slightly incorporated into liver TG (from 0.0 +/- 0.0% to 2.3 +/- 0.7% and 1.2 +/- 0.4% for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) respectively, with LCT + FO), but remained undetectable in extrahepatic tissue TG. Of interest, medium chain FA were found in tissue TG after infusion of the mixed MCT/LCT emulsions. As expected, changes of tissue phospholipid (PL) composition involved only long-chain FA. Infusion of soya bean oil emulsion was associated with an increased content of linoleate in liver PL (from 13.6 +/- 0.4% to 17.7 +/- 0.4%), but not in other tissues. MCT/LCT did not markedly affect PL/FA pattern in any tissue. Supplementation with fish oil was associated with an efficient incorporation of n-3FA into tissue PL, particularly in the liver (from 0.4 +/- 0.1% to 2.5 +/- 0.3% for EPA and from 3.9 +/- 0.8% to 9.1 +/- 0.4% for DHA, with the LCT + FO emulsion).     

The effect of long-term supplementation with different dietary ω-6/ω-3 ratios on mineral content and ex vivo prostaglandin E2 release in bone of growing rabbits

BACKGROUND/OBJECTIVES

The aim of this research was to study the different long term effects of consumption of dietary oil sources with varying omega-6/omega-3 (ω-6/ω-3) polyunsaturated fatty acids (PUFAs) ratios on bone marrow fatty acid level, ex vivo prostaglandin E₂ (PGE₂) release, and mineral content of bone in rabbits.

MATERIALS/METHODS

For this purpose, weaning and female New Zealand white rabbits were purchased and randomly divided into five groups and offered ad libitum diets containing 70 g/kg of added oil for 100 days. The dietary lipid treatments were formulated to provide the following ratios of ω-6/ω-3 fatty acids: 8.68 soy bean oil (SBO control), 21.75 sesame oil (SO), 0.39 fish oil (FO), 0.63 algae oil (DHA), and 0.68 algae oils (DHA/ARA). DHA and ARA are two types of marine microalgae of the genus Crypthecodinium cohnii.

RESULTS

The dietary treatments had significant effects on the bone marrow fatty acids of rabbits. Rabbits fed the FO diet, containing the highest ω-3 PUFA concentration, and those fed the SBO diet showed the highest ω-6 PUFA. On the other hand, a positive correlation was observed between Ex vivo PGE₂ level and the ω-6/ω-3 dietary ratio. Significant effects of dietary treatment on femur Ca, P, Mg, and Zn contents were observed in both genders.

CONCLUSIONS

Findings of the current study clearly demonstrated that dietary PUFA, particularly ω-6/ω-3 and ARA/EPA ratios are important factors in determining bone marrow fatty acid profile, and this in turn determines the capacity of bone for synthesis of PGE₂, thereby reducing bone resorption and improving bone mass during growth.     

Associations of Vitamin B6 Intake and Plasma Pyridoxal 5′-Phosphate with Plasma Polyunsaturated Fatty Acids in US Older Adults: Findings from NHANES 2003–2004

Previous evidence suggests a potential dual impact of aging and vitamin B6 (B6) deficiency on polyunsaturated fatty acid (PUFA) metabolism; gender may influence PUFA biosynthesis. Perturbation of PUFA compositions during B6 deficiency could be linked to age-related health outcomes. However, little is known about the interrelationships between vitamin B6, PUFA, and gender in the older population. Therefore, we investigated whether gender-specific associations of B6 intake and plasma pyridoxal 5’-phosphate (PLP) concentration, respectively, with plasma PUFA concentrations and ratios (eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA), EPA + DHA, EPA/AA, and (EPA + DHA)/AA) existed in older adults. We further examined the relationships of adequate B6 status (PLP ≥ 20 nmol/L) with high (above median) plasma PUFA relative to deficient B6 status. This cross-sectional study analyzed 461 participants aged ≥60 years from NHANES 2003–2004. Nutrient intakes were assessed using two 24-h recalls and supplement questionnaires. PLP and PUFA concentrations were measured. Multivariate linear regression assessed the association of B6 intake and PLP with PUFA; multivariate logistic regression evaluated the relationship of adequate B6 status with high plasma PUFA, adjusting for demographic, socioeconomic, and dietary factors; physical activity; smoking; alcohol; medication; and BMI. There were interactions between gender and B6 intake on EPA (P-_interaction = 0.008) and AA (P-_interaction = 0.004) only, whereas no interaction existed between gender and PLP on PUFA. PLP was directly associated with EPA (β = 0.181, P = 0.002), DHA (β = 0.109, P = 0.005), EPA + DHA (β = 0.14, P = 0.002), EPA/AA (β = 0.186, P = 0.004), and (EPA + DHA)/AA (β = 0.13, P = 0.026). The odds of having high plasma EPA (adjusted (a) OR: 2.03, P = 0.049) and EPA/AA (aOR: 3.83, P < 0.0001) were greater in those with adequate B6 status compared to those with deficient B6 status. In conclusion, in US older adults, a higher PLP level was associated with a greater level of EPA, DHA, EPA + DHA, EPA/AA, and (EPA + DHA)/AA. Adequate B6 status was associated with high EPA and EPA/AA status. These findings suggest that sufficient vitamin B6 status may positively influence PUFA metabolism in older adults.     

Plasma and Red Blood Cell PUFAs in Home Parenteral Nutrition Paediatric Patients—Effects of Lipid Emulsions

Background: Mixed lipid emulsions (LE) containing fish oil present several advantages compared to the sole soybean oil LE, but little is known about the safety of essential fatty acids (EFA) profile in paediatric patients on long-term Parenteral Nutrition (PN). Aim of the study: to assess glycerophosfolipid polyunsaturated fatty acids (PUFA) levels on plasma and red blood cell (RBC) membrane of children on long term PN with composite LE containing fish oil (SMOF), and to compare it with a group receiving olive oil LE (Clinoleic^®) and to the reference range for age, previously determined on a group of healthy children. Results: A total of 38 patients were enrolled, median age 5.56 (0.9–21.86) years, 15 receiving Clinoleic^®, 23 receiving SMOF. Patients on SMOF showed significantly higher levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), lower levels of arachidonic acid (ARA) and Mead acid (MEAD)/ARA ratio in plasma and RBC compared with patients on Clinoleic^® and with healthy children. Triene:tetraene (T:T) ratio of both groups of patients did not differ from that of healthy children-median plasma (MEAD/ARA: 0.01, interquartile rage (IQR) 0.01, p = 0.61 and 0.02, IQR 0.02, p = 0.6 in SMOF and Clinoleic^® patients, respectively), and was considerably lower than Holman index (>0.21). SMOF patients showed no statistically significant differences in growth parameters compared with Clinoleic^® patients. Patients of both groups showed stiffness class F0-F1 of liver stiffness measure (LSM) 5.6 (IQR 0.85) in SMOF patients and 5.3 (IQR 0.90) in Clinoleic^® patients, p = 0.58), indicating absence of liver fibrosis. Conclusions: Fatty acids, measured as concentrations (mg/L), revealed specific PUFA profile of PN patients and could be an accurate method to evaluate nutritional status and eventually to detect essential fatty acid deficiency (EFAD). SMOF patients showed significantly higher EPA, DHA and lower ARA concentrations compared to Clinoleic^® patients. Both LEs showed similar hepatic evolution and growth.     

A Comparison of Fish Oil Sources for Parenteral Lipid Emulsions in a Murine Model

Background: Fat emulsions are important components of parenteral nutrition (PN). Fish oil (FO) emulsions reverse cholestasis in PN‐associated liver disease. There are 2 FO monographs. One is “FO; rich in omega‐3 fatty acids” (NFO). The other, “omega‐3 acids,” (PFO), is enriched in omega‐3 fatty acids, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The purpose of this study is to compare the effects of 20% NFO and PFO emulsions produced in the laboratory in a murine model. Methods: Emulsions were compounded containing different oils: soybean oil (SO), NFO, and two PFOs differing in percentage of fatty acids as triglycerides (PFO66 and PFO90). Chow‐fed mice received saline, one of the above emulsions, or a commercial FO (OM) intravenously (2.4 g/kg/day) for 19 days. On day 19, animals were euthanized. Livers, spleens, and lungs were procured for histologic analysis. Results: OM, SO, NFO, and PFO90 were well‐tolerated clinically. PFO66 resulted in tachypnea and lethargy for ~1 minute following injections. At euthanasia, PFO66 and PFO90 groups had organomegaly. Histologically, these groups had splenic and hepatic fat‐laden macrophages, and lungs had scattered fat deposits. Other groups had normal organs. Conclusions: PFO emulsions present an attractive possibility for improving inflammation in PN‐dependent patients by concentrating anti‐inflammatory EPA and DHA. However, 20% PFO emulsions were poorly tolerated and precipitated adverse end organ sequelae, suggesting that they may not be safe. Development of novel manufacturing methods may achieve safe 20% PFO parenteral emulsions, but by established formulation methods, these emulsions were clinically suboptimal despite meeting pharmacopeial standards.