Higher Docosahexaenoic Acid Concentrations Research Articles

Intravitreal docosahexaenoic acid in a rabbit model: preclinical safety assessment.

PurposeThe purpose of the present study was to evaluate the retinal toxicity of a single dose of intravitreal docosahexaenoic acid (DHA) in rabbit eyes over a short-term period.MethodsSixteen New Zealand albino rabbits were selected for this pre-clinical study. Six concentrations of DHA (Brudy Laboratories, Barcelona, Spain) were prepared: 10 mg/50 µl, 5 mg/50 µl, 2’5 mg/50 µl, 50 µg/50 µl, 25 µg/50 µl, and 5 µg/50 µl. Each concentration was injected intravitreally in the right eye of two rabbits. As a control, the vehicle solution was injected in one eye of four animals. Retinal safety was studied by slit-lamp examination, and electroretinography. All the rabbits were euthanized one week after the intravitreal injection of DHA and the eyeballs were processed to morphologic and morphometric histological examination by light microscopy. At the same time aqueous and vitreous humor samples were taken to quantify the concentration of omega-3 acids by gas chromatography. Statistical analysis was performed by SPSS 21.0.ResultsSlit-lamp examination revealed an important inflammatory reaction on the anterior chamber of the rabbits injected with the higher concentrations of DHA (10 mg/50 µl, 5 mg/50 µl, 2'5 mg/50 µ) Lower concentrations showed no inflammation. Electroretinography and histological studies showed no significant difference between control and DHA-injected groups except for the group injected with 50 µg/50 µl.ConclusionsOur results indicate that administration of intravitreal DHA is safe in the albino rabbit model up to the maximum tolerated dose of 25 µg/50 µl. Further studies should be performed in order to evaluate the effect of intravitreal injection of DHA as a treatment, alone or in combination, of different retinal diseases.

Role of Omega-3 Polyunsaturated fatty acids in Inflammation and rheumatoid arthritis disorders

Reviewing the relationships between polyunsaturated FAs (PUFAs) with inflammation and rheumatoid arthritis disorders, the PUFAs containing ω-3, ω-6 and ω-9, these ω-3FAs levels were correlated with ω-6: ω-3 ratios including arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Based on previously-reports, the levels of ω-3 FAs considered being as a 'lower risk' category for inflammation and rheumatoid arthritis. Certain PUFAs ratios may aid in inflammation and rheumatoid arthritis-related risk assessment. PUFA are the most effective for the production of oil with high concentration of DHA and EPA content significantly.DOI: http://dx.doi.org/10.3126/ijasbt.v2i1.9783Int J Appl Sci Biotechnol, Vol. 2(1): 3-17

Tracking Diet Preferences of Bats Using Stable Isotope and Fatty Acid Signatures of Faeces

Stable isotope and fatty acid signatures of biomaterials can provide important information about the dietary niche of animals. Stable isotope and fatty acid signatures differ between aquatic and terrestrial food webs, and therefore can be used to assess the aquatic and terrestrial contributions to the diets of species. We studied faecal samples of three co-occurring bat species with known differences in feeding preferences. The aim was to assess whether stable isotope and fatty acid signatures of faeces can be used to determine feeding preferences. We used bat faeces because they can be easily and non-invasively collected. We hypothesised that faeces stable isotope and fatty acid signatures will reveal the terrestrial, aquatic and mixed feeding niches of Myotis myotis, M. daubentonii, and M. mystacinus, respectively. As predicted, the faeces of M. myotis were characterized by higher δ 13C values and higher concentrations of linoleic acid and total ω6 polyunsaturated fatty acids (PUFAs), which are typically higher in terrestrial food webs. The faeces of M. daubentonii had higher δ 15Ν values and higher concentrations of docosahexaenoic acid and total ω3 PUFAs, characteristic features of aquatic systems. Myotis mystacinus faeces had intermediate δ 15Ν values and concentrations of both types of fatty acids. Our results show that analysing stable isotope and/or fatty acid signatures of faeces provides a promising, non-invasive tool to study the feeding ecology of bats and to assess aquatic-terrestrial interactions.

INCORPORATION OF OMEGA-3 FATTY ACID AND SYNTHESIS OF THEIR METABOLITES IN MUSCLE TISSUE IN MICE FED WITH FLAXSEED AND PERILLA-ENRICHED DIET

Polyunsaturated fatty acids omega 3 and omega 6 are believed to have beneficial physiological effects on the human body. The present study aimed to evaluate the incorporation and synthesis of omega-3 fatty a cid and their metabolites in muscle tissue in mice fed with a flaxseed and perilla-enriched diet. The anim als were fed a diet supplemented with flaxseed and peri lla meals for fifty-six days and control animals re ceived a commercial diet. Mice were sacrificed on the 7th, 28th and 56th days and the muscle tissue was colle cted. The FA concentration was analyzed by gas chromatography. The levels of alpha-Linolenic Acid (LNA) and their metabolites, Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) increased as a function of feeding length in the groups given the supplemen ted diet. LNA was incorporated into muscle tissue a nd conversion into Very Long Chain Polyunsaturated Fatty Acids (VLC-PUFA) was observed. The muscle tissue of animals fed with enriched diets presented a high sum of n-3 FA and high concentrations of LNA, EPA and DHA, as compared to mice fed commercial diet. The intake of flaxseed and perilla-meal enriched diets by mice may result in the deposition of LNA a nd its metabolites EPA and DHA into muscle tissue.

Isolation and characterization of Aurantiochytrium species: high docosahexaenoic acid (DHA) production by the newly isolated microalga, Aurantiochytrium sp. SD116

A heterotrophic microalga, strain SD116, with the ability to produce high concentrations of docosahexaenoic acid (DHA, C22:6n-3) was isolated from Shuidong Bay, Guangdong Province, China. Nucleotide sequence analysis of the 18S rDNA of SD116 showed that the strain has a close phylogenetic relationship to Aurantiochytrium species. The highest rates for growth and DHA accumulation for SD116 were obtained in 6.0% glucose, 2.0% yeast extract, and 50% artificial seawater (ASW) at a pH of 7 at 28°C. The maximum total lipid content reached 56.3% of the dry cell weight (DCW), and the maximum DHA content accounted for 50.9% of the total fatty acid (TFA) content. It was further found that urea may be a potential nitrogen source for industrial fermentation because of its cheap price and ability to induce a relatively high biomass and lipid production capacity. Using 5 L fermenters, the DCW, total lipid content, and DHA yield were found to be 70.43 g L(-1), 71.09% of the DCW, and 17.42 g L(-1) (34.79% of the TFA), respectively. The results show that Aurantiochytrium sp. SD116 is a promising candidate for commercial DHA production and could be useful for the synthesis of biomass-related products.

Enhancement of docosahexaenoic acid production by Schizochytrium sp. using a two-stage oxygen supply control strategy based on oxygen transfer coefficient

To improve the yield and productivity of docosahexaenoic acid (DHA) by Schizochytrium sp. in terms of the analysis of microbial physiology. A two-stage oxygen supply control strategy, aimed at achieving high concentration and high productivity of DHA, was proposed. At the first 40 h, K(L) a was controlled at 150·1 h(-1) to obtain high μ for cell growth, subsequently K(L) a was controlled at 88·5 h(-1) to maintain high q(p) for high DHA accumulation. Finally, the maximum lipid, DHA content and DHA productivity reached 46·6, 17·7 g l(-1) and 111 mg l(-1) h(-1), which were 43·83%, 63·88% and 32·14% over the best results controlled by constant K(L) a. This paper described a two-stage oxygen supply control strategy based on the kinetic analysis for efficient DHA fermentation by Schizochytrium sp. This study showed the advantage of two-stage control strategy in terms of microbial physiology. As K(L) a is a scaling-up parameter, the idea developed in this paper could be scaled-up to industrial process and applied to other industrial biotechnological processes to achieve both high product concentration and high productivity.

Effect of dietary DHA supplementation on sperm DNA integrity

OBJECTIVE: Oxidative stress is an imbalance between the amount of reactive oxygen species (ROS) produced and the ability of the antioxidants to scavenge these.High levels of ROS produce DNA damage which could cause infertility. Docosahexaenoic acid (DHA) is a polyunsaturated Omega-3 fatty acid and is found in high concentrations in sperm membranes.Several studies suggest an antioxidant capacity for DHA.The aim of this study is to evaluate the effect of Brudy Plus® an enzymatic nutraceutical triglyceride oil with a high concentration of DHA in damaged spermatozoa DNA.

Protective effect of Mediterranean fish oil extracts on heat-induced denaturation of albumin

Three oily extracts, obtained by acetone extraction from the entrails of different varieties of Mediterranean fishes, such as mackerel (Scomber scombrus), sardine (Sardina pilchardus) and horse mackerel (Trachurus mediterraneus), were characterized to determine their unsaturated fatty acid content. In an in-vitro model, their inhibitory effect was then evaluated against protein aggregation and their protective efficacy against heat-induced albumin denaturation assessed. The fish oil extracts tested in this study presented a significant amount of unsaturated fatty acids; in particular the extract obtained from the entrails of horse mackerel proved to have higher concentrations of DHA (docosahexaenoic acid) and oleic acid compared with the other two oils. The in-vitro study revealed an interesting protective effect of the oil extracts (particularly the horse mackerel extract) against heat-induced denaturation of albumin.

Selective decrease of bis(monoacylglycero)phosphate content in macrophages by high supplementation with docosahexaenoic acid

Bis(monoacylglycero)phosphate (BMP) is a unique phospholipid (PL) preferentially found in late endosomal membranes, where it forms specialized lipid domains. Recently, using cultured macrophages treated with anti-BMP antibody, we showed that BMP-rich domains are involved in cholesterol homeostasis. We had previously stressed the high propensity of BMP to accumulate docosahexaenoic acid (DHA), compared with other PUFAs. Because phosphatidylglycerol (PG) was reported as a precursor for BMP synthesis in RAW macrophages, we examined the effects of PG supplementation on both FA composition and amount of BMP in this cell line. Supplementation with dioleoyl-PG (18:1/18:1-PG) induced BMP accumulation, together with an increase of oleate proportion. Supplementation with high concentrations of didocosahexaenoyl-PG (22:6/22:6-PG) led to a marked enrichment of DHA in BMP, resulting in the formation of diDHA molecular species. However, the amount of BMP was selectively decreased. Similar effects were observed after supplementation with high concentrations of nonesterified DHA. Addition of vitamin E prevented the decrease of BMP and further increased its DHA content. Supplementation with 22:6/22:6-PG promoted BMP accumulation with an enhanced proportion of 22:6/22:6-BMP. DHA-rich BMP was significantly degraded after cell exposure to oxidant conditions, in contrast to oleic acid-rich BMP, which was not affected. Using a cell-free system, we showed that 22:6/22:6-BMP is highly oxidizable and partially protects cholesterol oxidation, compared with 18:1/18:1-BMP. Our data suggest that high DHA content in BMP led to specific degradation of this PL, possibly through the diDHA molecular species, which is very prone to peroxidation and, as such, a potential antioxidant in its immediate vicinity.

Effects of docosahexaenoic acid on some megakaryocytic cell gene expression of some enzymes controlling prostanoid synthesis

Beneficial effects of docosahexaenoic acid (DHA) intake in the prevention of cardiovascular diseases are known, and platelets play a crucial role in cardiovascular complications. However, high doses of DHA may increase lipid peroxidation and induce deleterious effects, notably in platelets. This led us to investigate the effect of DHA on gene expression of some enzymes controlling redox status and prostanoid formation in human megakaryoblastic cells (MEG-01 cell line). MEG-01 cells were incubated in presence of DHA (10 and 100 μmol/L) for 6 h. DHA enrichment up-regulated glutathione peroxidase-1 and thromboxane synthase mRNA. DHA increased gene catalase expression and up-regulated PPAR β/δ and PPAR γ mRNA in presence of high concentration of DHA. In conclusion, our results support an antioxidant mechanism of DHA. The effects of DHA on cellular redox status could, with others, provide an explanation for the beneficial influence of low consumption of DHA on cardiovascular events.

Association of fatty acids in serum phospholipids with lung function and bronchial hyperresponsiveness in adults

The dietary intake of certain fatty acids might have an impact on inflammatory processes in the lung and therefore contribute to the development of lung diseases like asthma or COPD. In this study data from a population based cross-sectional study on respiratory health including measurement of fatty acids in serum phospholipids of 593 adults between 20 and 64 years of age were analyzed. Statistically significant positive associations were found between percentage predicted FEV1 (P = 0.0085) and FVC (P = 0.0267) and docosahexaenoic acid concentration in serum phospholipids in men. Dihomo-gamma-linolenic acid content in serum phospholipids was significantly negatively associated with percentage predicted FEV1 (P = 0.0003) and FVC (P = 0.0045) and transformed dose-response slopes (P = 0.0488) in men. Palmitoleic acid was negatively associated with percentage predicted FEV1 (P = 0.0037) and FVC (P = 0.0029) in men. Other fatty acids in serum phospholipids did not consistently affect lung function parameters or bronchial hyperreactivity. A high concentration of docosahexaenoic acid in serum phospholipids may have a protective effect on lung function. Because this long-chain n-3 polyunsaturated fatty acid is almost exclusively derived from marine oils, fish might have a beneficial effect on lung diseases.

Maternal Organo-Selenium Compounds and Polyunsaturated Fatty Acids Affect Progeny Performance and Levels of Selenium and Docosahexaenoic Acid in the Chick Tissues

The effects of supplementing broiler breeder diets with polyunsaturated fatty acids (PUFA) and organo-Se compounds on the levels of Se and PUFA in chick tissues and on chick performance were assessed. Prepeak (23 wk) and peak (27 wk) production broiler breeders were fed 1 of 4 diets: a wheat-based commercial diet with soybean oil or fish oil but no added Se, and each diet with added Se as Sel-Plex (soybean oil + Se, fish oil + Se; Alltech Inc, Nicholasville, KY). The diets were designed to contain less than 0.1 mg of Se/kg and about 0.5 mg/kg for the nonsupplemented and the supplemented diets, respectively. As-hatched chicks from the 4 parental treatments were fed a nutritionally high quality diet (ME = 12.57 MJ/kg; CP = 228.7 g/kg) or a low quality diet (ME = 10.28 MJ/kg; CP = 182.8 g/kg), resulting in 8 dietary treatments. Performance was better and mortality lower in chicks from 27-wk-old breeders compared with those from 23-wk-old breeders. Fish oil in the maternal diet increased progeny mortality and reduced chick body mass at hatch. Body mass at 7 and 14 d posthatch was lower in chicks fed the low quality diet compared with chicks fed the high quality diet. At hatch, and for up to 14 d posthatch, chicks from hens fed diets high in PUFA had higher concentrations of docosahexaenoic acid (DHA) in the brain and liver compared with chicks hatched from hens fed diets low in PUFA. The DHA content of the tissues of chicks from breeders fed diets supplemented with Se was higher than that in chicks from breeders fed unsupplemented diets. Even after 14 d of being fed a diet with identical levels of Se, chicks hatched from parents fed diets high in Se had higher tissue Se concentrations than those hatched from parents fed diets low in Se. Supplementation of the maternal diet of chicks with organo-Se appears to enhance the DHA concentration of the chick brain, which may improve brain function.

Effects of docosahexaenoic acid on the survival and neurite outgrowth of rat cortical neurons in primary cultures

Effects of docosahexaenoic acid (DHA) on survival and neurite outgrowth were investigated in primary cultures of rat cortical neurons. Cell cultures were prepared from cortex on embryonic day 18 (E-18) for treatment with a series of DHA concentrations (12.5, 25, 50, 75, 100 and 200 μM). Docosahexaenoic acid (25–50 μM) significantly enhanced neuronal viability, but lower concentration of DHA (12.5 μM) did not show an obvious effect. In contrast, higher concentrations of DHA (100–200 μM) exerted the significant opposite effects by decreasing neuronal viability. Furthermore, treatment with 25 μM DHA significantly prevented the neurons from death after different culture days in vitro (DIV). Moreover, measurements from the cultures exposed to 25 μM DHA immediately after plating showed significant increases in the percentage of cells with neurites, the mean number of neurite branches, the total neuritic length per cell and the length of the longest neurite in each cell after 24 and 48 h in vitro (HIV). The DHA-treated neurons had greater growth-associated protein-43 (GAP-43) immunoactivity and higher phosphatidylserine (PS) and phosphatidylethanolamine (PE) contents, but lower phosphatidylcholine (PC) content than control neurons. The significant increased DHA contents were also observed in both PE and PS in the treated neurons. These findings suggest that optimal DHA (25 μM) may have positive effects on the survival and the neurite outgrowth of the cultured fetal rat cortical neurons, and the effects probably are related to DHA-stimulating neuron-specific protein synthesis and its enhancing the discrete phospholipid (PL) content through enrichment of DHA in the PL species.

The environment of increased concentration of docosahexaenoic acid in glioblastoma may suppress the anti-tumor effect of macrophages

Regarding glioblastoma, there has been controversy over whether a large number of infiltrating macrophages act as anti-tumor effectors or not. It has been exhibited that intratumoral lipid environments have a possible influence on anti-tumor immunity. Necrosis of glioblastoma and non-necrotic tissues of astrocytic tumors were analyzed to compare the amount of free docosahexaenoic acid (DHA) content. The apoptosis inducible effects of DHA on macrophages derived from peripheral blood monocytes and cultured glioma cells were evaluated by flow cytometry. The influence of DHA on the anti-tumor effects of macrophages was assessed at 0, 30, 60, and 90 mM of DHA by (51)Cr releasing assay and MTT assay. The mean concentration of free DHA in necrotic tissues (757.6 mmol/kg) was 5 times higher than that in non-necrotic tissues (147.2 mmol/kg). The DHA concentration of 30 mM induced apoptosis in macrophages, however, glioma cells were not affected even at a DHA concentration of 60 mM. Macrophages pre-exposed to DHA for 24 h decreased the cytotoxicity to U251MG cells as shown by (51)Cr releasing assay. Total viability of co-cultured macrophages and U251MG cells showed an increase at high concentrations of DHA (60 and 90 mM) according to 24 h MTT assay, although each separate culture did not. The DHA concentration in necrosis of glioblastoma was sufficient for macrophages to cause apoptosis and suppress their anti-tumor effects. The results suggest that liberated DHA in necrosis can induce apoptosis in macrophages and inhibit their functions.

Docosahexaenoic acid concentrations are higher in women than in men because of estrogenic effects

During pregnancy there is a high demand for docosahexaenoic acid (DHA), which is needed for formation of the fetal brain. Women who do not consume marine foods must synthesize DHA from fatty acid precursors in vegetable foods. We studied sex differences in DHA status and the role of sex hormones. First, DHA status was compared between 72 male and 103 female healthy volunteers who ate the same rigidly controlled diets. Second, the effects of sex hormones were studied in 56 male-to-female transsexual subjects, who were treated with cyproterone acetate alone or randomly assigned to receive oral ethinyl estradiol or transdermal 17beta-estradiol combined with cyproterone acetate, and in 61 female-to-male transsexual subjects, who were treated with testosterone esters or randomly assigned for treatment with the aromatase inhibitor anastrozole or placebo in addition to the testosterone regimen. The proportion of DHA was 15 +/- 4% (x +/- SEM; P < 0.0005) higher in the women than in the men. Among the women, those taking oral contraceptives had 10 +/- 4% (P = 0.08) higher DHA concentrations than did those not taking oral contraceptives. Administration of oral ethinyl estradiol, but not transdermal 17beta-estradiol, increased DHA by 42 +/- 8% (P < 0.0005), whereas the antiandrogen cyproterone acetate did not affect DHA. Parenteral testosterone decreased DHA by 22 +/- 4% (P < 0.0005) in female-to-male transsexual subjects. Anastrozole decreased estradiol concentrations significantly and DHA concentrations nonsignificantly (9 +/- 6%; P = 0.09). Estrogens cause higher DHA concentrations in women than in men, probably by upregulating synthesis of DHA from vegetable precursors.

Perinatal biochemistry and physiology of long-chain polyunsaturated fatty acids

Docosahexaenoic acid (DHA) and arachidonic acid (ARA) are important structural components of the central nervous system. These fatty acids are transferred across the placenta, are present in human milk, and are accumulated in the brain and retina during fetal and infant development. The high concentrations of DHA in the retina and of DHA and ARA in brain gray matter suggests that these fatty acids have important roles in retinal and neural function. Animal studies have shown that depletion of DHA from the retina and brain results in reduced visual function and learning deficits. The latter effects may be explained by changes in the membrane bilayer that alter membrane-associated receptors and signal transduction systems, ion channel activity, or direct effects on gene expression. DHA can be formed in the liver from alpha linolenic acid, but it is unclear if the rate of DHA synthesis in humans is sufficient to support optimal brain and retinal development. Although there is no evidence that the ability to form ARA from linoleic acid is limiting, supplementation with DHA reduces tissue ARA, possibly creating a conditional need for ARA in infants with a dietary intake of DHA. The amount of DHA in human milk varies widely and is positively correlated with visual and language development in breast-fed infants. Advances in understanding essential fatty acid requirements will benefit from intervention studies that use functionally relevant tests to probe the deficiency or adequacy of physiologically important pools of DHA and ARA in developing infants.

Dietary conjugated linoleic acid with fish oil alters yolk n-3 and trans fatty acid content and volatile compounds in raw, cooked, and irradiated eggs

We investigated the effect of dietary conjugated linoleic acid (CLA) along with n-3 polyunsaturated fatty acid (n-3 PUFA) on yolk fatty acid composition and volatile compounds in eggs that were raw (RA), hard-boiled (HB), or hard-boiled, irradiated (HBI, 2.5 kGy). Single Comb White Leghorn laying hens (n = 40) were randomly assigned to one of the four experimental diets containing 0, 0.5, 1.0, or 2.0% CLA. Menhaden oil was used as the source of n-3 PUFA. Eggs collected after 6 wk of feeding were analyzed for fatty acids and volatile compounds. The content of docosahexaenoic acid (C22:6 n-3) was reduced (P < 0.05) in eggs from hens fed the 2.0% CLA diet. Eggs from hens fed 0.5% CLA incorporated the highest concentration of docosahexaenoic acid (P < 0.05) with a concomitant reduction in arachidonic acid (P < 0.05). The yolk contents of cis-9 trans-11 CLA and trans-10 cis-12 CLA increased linearly (P < 0.05) as the dietary CLA supply increased. Total monounsaturates were reduced (P < 0.05) with an increase in saturates in yolk. No difference was observed in the total PUFA content of eggs. Total volatiles were reduced in RA eggs from 1.0 and 2.0% CLA diets. 2-Propanone, hexane, and methyl cyclopentane were the major volatiles in RA eggs and were reduced by dietary CLA at 1.0 and 2.0%. Acetaldehyde, pentane, propanol, acetic acid methyl ester, acetic acid ethyl ester, propionic acid methyl ester, 2-methylmethyl propionic acid, 2-propanone, and octane were the major volatiles in HB eggs and were reduced by 2.0% CLA (P < 0.05). No difference was observed in the acetaldehyde, pentane, propanol, acetic acid ethyl ester, octane, or total volatile content of HBI eggs.

Seafood consumption, the DHA content of mothers’ milk and prevalence rates of postpartum depression: a cross-national, ecological analysis

Background: Mothers selectively transfer docosahexaenoic acid (DHA) to their fetuses to support optimal neurological development during pregnancy. Without sufficient dietary intake, mothers become depleted of DHA and may increase their risk of suffering major depressive symptoms in the postpartum period. We postulated that the DHA content of mothers’ milk and seafood consumption would both predict prevalence rates of postpartum depression across countries. Methods: Published prevalence data for postpartum depression were included that used the Edinburgh Postpartum Depression Scale ( n=14 532 subjects in 41 studies). These data were compared to the DHA, eicosapentaenoic acid (EPA) and arachidonic acid (AA) content in mothers’ milk and to seafood consumption rates in published reports from 23 countries. Results: Higher concentrations of DHA in mothers’ milk ( r=−0.84, p<0.0001, n=16 countries) and greater seafood consumption ( r=−0.81, p<0.0001, n=22 countries) both predicted lower prevalence rates of postpartum depression in simple and logarithmic models, respectively. The AA and EPA content of mothers’ milk were unrelated to postpartum depression prevalence. Limitations: These findings do not prove that higher omega-3 status cause lower prevalence rates of postpartum depression. Data on potentially confounding factors were not uniformly available for all countries. Conclusions: Both lower DHA content in mothers’ milk and lower seafood consumption were associated with higher rates of postpartum depression. These results do not appear to be an artifact of cross-national differences in well-established risk factors for postpartum depression. Interventional studies are needed to determine if omega-3 fatty acids can reduce major postpartum depressive symptoms.

A randomized controlled trial of long-chain polyunsaturated fatty acid supplementation of formula in term infants after weaning at 6 wk of age

The critical period during which the dietary supply of long-chain polyunsaturated fatty acids (LCPs) may influence the maturation of cortical function in term infants is unknown. The aim of the present study was to determine the relative importance for maturation of the visual cortex of the dietary supply of LCPs during the first 6 wk of life compared with that during weeks 7-52. A randomized controlled clinical trial of LCP supplementation in 65 healthy term infants who were weaned from breast-feeding at 6 wk of age was conducted to determine whether the dietary supply of LCPs after weaning influenced the maturation of visual acuity and stereoacuity. Despite a dietary supply of LCPs from breast milk during the first 6 wk of life, infants who were weaned to formula that did not provide LCPs had significantly poorer visual acuity at 17, 26, and 52 wk of age and significantly poorer stereoacuity at 17 wk of age than did infants who were weaned to LCP-supplemented formula. Better acuity and stereoacuity at 17 wk was correlated with higher concentrations of docosahexaenoic acid in plasma. Better acuity at 52 wk was correlated with higher concentrations of docosahexaenoic acid in plasma and red blood cells. No significant effects of diet on growth were found. The results suggest that the critical period during which the dietary supply of LCPs can influence the maturation of cortical function extends beyond 6 wk of age.

Detection of docosahexaenoic acid hydroperoxides in retina by gas chromatography/mass spectrometry.

AbstractIn the retina, as well as in other organs, inflammation-mediated membrane lipid peroxidation is regarded as the major source of unsaturated fatty acid hydroperoxides. It is generally accepted that inflammatory infiltrates, such as polymorphonuclear leukocytes and macropahges, simultaneously generate superoxide and nitric oxide (NO) (1). Although both radicals display low chemical reactivity, their combination product, peroxynitrite, is a potent oxidant capable of oxidizing cellular macromolecules, including membrane lipids (2). Photoreceptor membranes in the retina contain an unusually high concentration of docosahexaenoic acid (22:6, omega 3), amounting to nearly 50% of the total fatty acid pool (3). By virtue of its structure, 22:6 is particularly susceptible to lipid peroxidation induced by peroxynitrite (2,2).Peroxidation of photoreceptor membranes in the retina has been recognized as a key component in various types of photoreceptor degeneration and pathogenesis (5). Interest in the pathological consequences of photoreceptor membrane lipid peroxidation has led to the development of several analytical approaches designed to detect peroxidized lipids in the retina.KeywordsDocosahexaenoic AcidButylate HydroxytoluenePositional IsomerTrimethylsilyl EtherFatty Acid MoietyThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.