Correction: Safety of a novel feed ingredient, Algal Oil containing EPA and DHA, in a gestation-lactation-growth feeding study in Beagle dogs.

[This corrects the article DOI: 10.1371/journal.pone.0217794.].

Safety of Algal Oil Containing EPA and DHA in cats during gestation, lactation and growth.

Algal Oil Containing EPA and DHA (AOCED) at approximately 50% was developed as a sustainable n-3 fatty acid source. AOCED was incorporated in diets at dose levels of 0%, 0.75%, 1.5% and 3.0% (w/w) and administered to healthy domestic shorthair female cats starting two weeks before mating, then during mating, gestation, lactation and to their kittens until they reached 32 weeks of age. The diets were made isocaloric and met the Association of American Feed Control Officials (AAFCO) nutrient requirements of cats for growth and reproduction. Dietary AOCED treatment did not affect the overall health, physiological parameters, food consumption and body weights of the queens and their kittens. No AOCED-related changes in haematology, coagulation or clinical chemistry parameters were observed in either generation when compared to control cats. Plasma levels of EPA and DHA were dose-dependently increased in both generations, demonstrating bioavailability of the fatty acids. In this study, safety of AOCED at levels up to 3.0% in the diet was demonstrated in cats with administration starting in utero and until kittens reached 32 weeks of age. Bioavailability of EPA and DHA in cats supports use of AOCED as a source of EPA and DHA for feline growth and reproduction.

Safety of a novel feed ingredient, Algal Oil containing EPA and DHA, in a gestation-lactation-growth feeding study in Beagle dogs.

An Algal Oil Containing EPA and DHA (AOCED) at ~50% was developed as a sustainable source of omega-3 fatty acids. AOCED was incorporated into extruded dry foods for dogs at 0, 0.75%, 1.5% and 3.0% levels (equivalent to 0, 7.5, 15 and 30 g/kg diet) on dry matter basis at the expense of chicken fat and fed to healthy female Beagle dogs starting at mating and throughout gestation and lactation. The offspring were fed their maternal corresponding diets for 26 weeks after weaning. AOCED-enriched diets were well tolerated by dogs in both generations and did not affect their overall health, physiological parameters, food consumption, body weights and body weight gains. There were no changes in hematology, clinical chemistry, and coagulation parameters in both generations of dogs fed the AOCED diets when compared to those in the control group. Plasma levels of DHA and EPA increased significantly and generally dose-dependently in both generations. The study demonstrated the safety of AOCED in dogs during gestation, lactation, and growth periods at dietary levels up to 3.0wt%, equivalent to 30 g/kg diet. AOCED's bioavailability as a source of DHA and EPA in dogs was demonstrated by the increased plasma concentrations of these nutritional lipids.

Kinetics of docosahexaenoic acid ethyl ester accumulation in dog plasma and brain.

This study explores dog plasma and brain fatty acid composition achieved after long-term supplementation at high DHA doses. A 90% concentrate of DHA Ethyl Ester (DHA-EE) administered by oral gavage to Beagle dogs at doses of 100, 500, 1000, and 2000mg/kg bw/day for 8 weeks resulted in DHA increases in both plasma and brain. In a subsequent 9-month study, DHA-EE was administered at 150, 1000 and 2000mg/kg bw/day. Plasma DHA increased between 150 and 1000mg/kg bw/day but not between 1000 and 2000mg/kg bw/day and there were increases from Day 1to 92 but not between days 92 and 273. Doses >500mg/kg bw/day in the 8-week and all doses in the 9-month study resulted in DHA increases in the brain. The dose of 150mg/k gbw/day is sufficient to achieve maximal brain concentrations if DHA is administered chronically. For shorter than 6 months of supplementation, higher doses are required.

The effect of APOE genotype on the delivery of DHA to cerebrospinal fluid in Alzheimer's disease.

BACKGROUND: Apolipoprotein E (APOE) ɛ4 and low cerebrospinal fluid (CSF) amyloid-ß42 (Aß42) levels are predictors for developing Alzheimer's disease (AD). The results of several studies indicate an interaction between docosahexaenoic acid (DHA) consumption and cognitive outcomes by APOE genotype. Our objective in the present study was to examine whether APOE ɛ4 genotype and low CSF Aß42 levels were associated with reduced delivery of DHA to CSF in the Alzheimer's Disease Cooperative Study-sponsored DHA clinical trial. METHODS: Phospholipid DHA was assayed in the plasma of 384 participants and CSF of 70 participants at baseline. Forty-four of the 70 participants completed the 18-month follow-up visit after allocation to placebo (n = 15) or DHA (n = 29). Plasma and CSF DHA levels, CSF Aß42, Tau, and phosphorylated Tau were measured at baseline and after the 18-month intervention. Participants were divided into tertiles based on baseline Aß42 CSF levels. To assess DHA delivery across the blood-brain barrier, the ratio of CSF to plasma DHA levels was calculated. RESULTS: At baseline, there were no significant differences between CSF or plasma phospholipid DHA levels by CSF Aß42 tertiles or ɛ4 status. After 18 months of DHA supplementation, participants at the lowest Aß42 tertile had significantly lower CSF DHA levels (p = 0.01) and lower CSF-to-plasma DHA ratios (p = 0.05) compared to the other tertiles. Baseline CSF Aß42 levels were significantly lower in ɛ4 carriers than in ɛ4 noncarriers (p = 0.01). Participants carrying the ɛ4 allele (n = 25) demonstrated a less pronounced increase in CSF DHA level compared with noncarriers (n = 4), with a possible interaction effect between treatment and APOE genotype (p = 0.07). CONCLUSIONS: APOE ɛ4 allele and lower CSF Aß42 levels were associated with less transport of DHA to CSF. Brain amyloid pathology may limit the delivery of DHA to the brain in AD. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT00440050 . Registered on 22 Feb 2007.

Similar eicosapentaenoic acid and docosahexaenoic acid plasma levels achieved with fish oil or krill oil in a randomized double-blind four-week bioavailability study.

BACKGROUND: Long-chain n-3 polyunsaturated fatty acids (LC n-3-PUFA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) provide multiple health benefits for heart, brain and eyes. However, consumption of fatty fish, the main source of LC n-3-PUFAs is low in Western countries. Intakes of LC n-3-PUFA can be increased by taking dietary supplements, such as fish oil, algal oil, or krill oil. Recently, conflicting information was published on the relative bioavailability of these omega-3 supplements. A few studies suggested that the phospholipid form (krill) is better absorbed than the fish oil ethyl ester (EE) or triglyceride (TG) forms. Yet studies did not match the doses administered nor the concentrations of DHA and EPA per supplement across such comparisons, leading to questionable conclusions. This study was designed to compare the oral bioavailability of the same dose of both EPA and DHA in fish oil-EE vs. fish oil-TG vs. krill oil in plasma at the end of a four-week supplementation. METHODS: Sixty-six healthy adults (n = 22/arm) were enrolled in a double blind, randomized, three-treatment, multi-dose, parallel study. Subjects were supplemented with a 1.3 g/d dose of EPA + DHA (approximately 816 mg/d EPA + 522 mg/d DHA, regardless of formulation) for 28 consecutive days, as either fish oil-EE, fish oil-TG or krill oil capsules (6 caps/day). Plasma and red blood cell (RBC) samples were collected at baseline (pre-dose on Day 1) and at 4, 8, 12, 48, 72, 336, and 672 h. Total plasma EPA + DHA levels at Week 4 (Hour 672) were measured as the primary endpoint. RESULTS: No significant differences in total plasma EPA + DHA at 672 h were observed between fish oil-EE (mean = 90.9 ± 41 ug/mL), fish oil-TG (mean = 108 ± 40 ug/mL), and krill oil (mean = 118.5 ± 48 ug/mL), p = 0.052 and bioavailability differed by < 24 % between the groups. Additionally, DHA + EPA levels were not significantly different in RBCs among the 3 formulations, p = 0.19, providing comparable omega-3 indexes. CONCLUSIONS: Similar plasma and RBC levels of EPA + DHA were achieved across fish oil and krill oil products when matched for dose, EPA, and DHA concentrations in this four week study, indicating comparable oral bioavailability irrespective of formulation. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT02427373.

Metabolism and biological production of resolvins derived from docosapentaenoic acid (DPAn-6).

17S-HDPAn-6 (17S-hydroxydocosa-4Z,7Z,10Z,13Z,15E-pentaenoic acid) and 10S,17S-HDPAn-6 (10S,17S-dihydroxydocosa-4Z,7Z,11E,13Z,15E-pentaenoic acid) are potent anti-inflammatory resolvins derived from DPAn-6 (docosapentaenoic acid n-6) and are analogous in structure and action to DHA (docosahexaenoic acid)-derived resolvins. These resolvins have proven to be potential drug candidates, albeit with therapeutic profiles that need optimization. The main objectives of this study were to evaluate key features of DPAn-6 derived resolvins that are important for therapeutic efficacy, demonstrate that these DPAn-6 resolvins could be produced naturally, and could therefore have physiological significance. Here we demonstrate biological production, examine pharmacokinetic profiles and identify key routes of metabolic inactivation of DPAn-6 derived resolvins. We compare their metabolic stability to a known resolvin, 17S-HDHA (17S-hydroxydocosa-4Z,7Z,10Z,13Z,15E,19Z-hexaenoic acid) and show that order of their stabilities is 10S,17S-HDPAn-6>17S-HDPAn-6>17S-HDHA. We show that both these compounds are not strong inhibitors of cytochrome-P450 enzymes. We evaluate activity of compounds in the delayed-type hypersensitivity model, results of which show that compounds need optimization for enhanced duration and magnitude of action. Analysis of the metabolic stability and identification of metabolites of these compounds could play an important role in the design of better analogs with longer durations of action and hence better efficacy.

The hypolipidemic effect of an ethyl ester of algal-docosahexaenoic acid in rats fed a high-fructose diet.

Preclinical and clinical studies demonstrate that the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) as a triacylglycerol (TAG) or an ethyl ester are protective against cardiovascular disease. Both have significant TAG-lowering effects. We developed a concentrated ethyl ester of DHA (MATK-90, 900 mg/g) using microalgae as its source. This study evaluated the effects that different doses of MATK-90 had on lipid levels and clinical parameters in male Wistar rats fed a high-fructose diet used to induce hypertriglyceridemia (TAG > or = 300 mg/dL). Effects of MATK-90 were compared to those produced by a pharmaceutical product (Lovaza, formerly Omacor, P-OM3; 465 mg EPA + 375 mg DHA), a TAG oil used in food (DHASCO, algal-DHA, 40% DHA by weight), and a control (corn oil). Doses of MATK-90 (0.6, 1.3, 2.5, 5.0 g kg(-1) day(-1)), algal-DHA (2 g DHA kg(-1) day(-1)), and P-OM3 (5.0 g kg(-1) day(-1)) were administered by oral gavage for 28 days. A significant dose-related decrease was observed in TAG and cholesterol levels in all but the lowest dose of MATK-90 treatment group vs. control. The high-dose group of MATK-90 and the P-OM3 group produced similar reductions in TAG levels.

Algal-oil capsules and cooked salmon: nutritionally equivalent sources of docosahexaenoic acid.

Food and nutrition professionals question whether supplement-sourced nutrients appear to be equivalent to those derived from natural food sources. We compared the nutritional availability of docosahexaenoic acid (DHA) from algal-oil capsules to that from assayed cooked salmon in 32 healthy men and women, ages 20 to 65 years, in a randomized, open-label, parallel-group study. In this 2-week study comparing 600 mg DHA/day from algal-oil capsules to that from assayed portions of cooked salmon, mean change from baseline in plasma phospholipids and erythrocyte DHA levels was analyzed and DHA levels were compared by Student's t tests. In post-hoc analyses to determine bioequivalence, least-squares mean ratios of percent change from baseline in plasma phospholipid and erythrocyte DHA levels were compared. DHA levels increased by approximately 80% in plasma phospholipids and by approximately 25% in erythrocytes in both groups. Changes in DHA levels in plasma phospholipids and erythrocytes were similar between groups. As measured by delivery of DHA to both plasma and erythrocytes, fish and algal-oil capsules were equivalent. Both regimens were generally well-tolerated. These results indicate that algal-oil DHA capsules and cooked salmon appear to be bioequivalent in providing DHA to plasma and red blood cells and, accordingly, that algal-oil DHA capsules represent a safe and convenient source of non-fish-derived DHA.

Validation of a rapid measure of blood PUFA levels in humans.

An assay involving a finger stick and filter paper blood spotting was developed to determine polyunsaturated fatty acid (PUFA) levels in blood. Capillary whole blood from a finger stick was blotted on antioxidant impregnated filter paper, air dried, saponified and methylated using sodium hydroxide and boron trifluoride in methanol. The method differed from those described previously because separation of plasma and red blood cells (RBCs) was not needed, thin-layer chromatography (TLC) was not required to separate phospholipids, initial extraction of lipids before transesterification was not necessary, and the fatty acid methyl ester (FAME) method was able to methylate steryl esters, free fatty acids, and sphingomyelins. Twenty-six subjects provided blood samples by finger stick and venipuncture. Levels of long-chain polyunsaturated fatty acids (LC-PUFA) from capillary whole blood were correlated with those from RBCs and PLs in venous blood (P < 0.001, R(2) ranged from 0.64 to 0.86). Although highly significant (P < 0.002), the R(2) values for the correlation between arachidonic acid (ARA) levels in capillary whole blood with ARA levels in RBCs and plasma phospholipids (PLs) were relatively lower (R(2) = 0.31-0.41, respectively). Results indicate that the described finger stick assay represents a fast, reliable method to measure specific LC-PUFA levels.

Bioequivalence of Docosahexaenoic acid from different algal oils in capsules and in a DHA-fortified food.

Docosahexaenoic acid (DHA), a long-chain omega-3 fatty acid, is important for eye and brain development and ongoing visual, cognitive, and cardiovascular health. Unlike fish-sourced oils, the bioavailability of DHA from vegetarian-sourced (algal) oils has not been formally assessed. We assessed bioequivalence of DHA oils in capsules from two different algal strains versus bioavailability from an algal-DHA-fortified food. Our 28-day randomized, placebo-controlled, parallel group study compared bioavailability of (a) two different algal DHA oils in capsules ("DHASCO-T" and "DHASCO-S") at doses of 200, 600, and 1,000 mg DHA per day (n = 12 per group) and of (b) an algal-DHA-fortified food (n = 12). Bioequivalence was based on changes in plasma phospholipid and erythrocyte DHA levels. Effects on arachidonic acid (ARA), docosapentaenoic acid-n-6 (DPAn-6), and eicosapentaenoic acid (EPA) were also determined. Both DHASCO-T and DHASCO-S capsules produced equivalent DHA levels in plasma phospholipids and erythrocytes. DHA response was dose-dependent and linear over the dose range, plasma phospholipid DHA increased by 1.17, 2.28 and 3.03 g per 100 g fatty acid at 200, 600, and 1,000 mg dose, respectively. Snack bars fortified with DHASCO-S oil also delivered equivalent amounts of DHA on a DHA dose basis. Adverse event monitoring revealed an excellent safety and tolerability profile. Two different algal oil capsule supplements and an algal oil-fortified food represent bioequivalent and safe sources of DHA.