Important Long-chain Polyunsaturated Fatty Acids Research Articles

Роль довголанцюгових поліненасичених жирних кислот у харчуванні немовлят

Довголанцюгові поліненасичені жирні кислоти (ДЛПНЖК) є основними функціональними жирами материнського молока. Переважаючими та функціонально найважливішими ДЛПНЖК є арахідонова (АК) і докозогексаєнова кислота (ДГК). Крім імітації складу грудного молока, існують ще дві важливі причини, щоб додавати ДЛПНЖК у молочні суміші для немовлят. По-перше, немовлята не можуть синтезувати достатню кількість ДЛПНЖК, щоб компенсувати відсутність цих речовин у продуктах харчування. По-друге, тканина мозку, сітківка очей та імунна система потребують великої кількості ДЛПНЖК як будівельного матеріалу та функціональних складових, щоб підтримати інтенсивний ріст і розвиток у ранньому дитинстві. Цей період є критичним для формування та розвитку цих органів, тому оптимальне постачання субстратів є необхідним для їх оптимального функціонування. Ці ідеї в поєднанні з результатами понад 20 рандомізованих контрольованих клінічних випробувань і численних інших досліджень, що доводять позитивний вплив харчових ДЛПНЖК на здоров’я й розвиток немовлят, свідчать про необхідність збагачення продуктів дитячого харчування ДГК і АК. Найбільш вивченими позитивними ефектами такого збагачення є поліпшення зорової функції і когнітивного розвитку дітей раннього віку. Нові дані пов’язують підвищене споживання ДЛПНЖК із корисним впливом на імунні функції і серцево-судинну систему малюків.

Parasitic Chytrids Upgrade and Convey Primary Produced Carbon During Inedible Algae Proliferation

Microbial parasites have only recently been included in planktonic food web studies, but their functional role in conveying dietary energy still remains to be elucidated. Parasitic fungi (chytrids) infecting phytoplankton may constitute an alternative trophic link and promote organic matter transfer through the production of dissemination zoospores. Particularly, during proliferation of inedible or toxic algal species, such as large Cyanobacteria fostered by global warming, parasites can constitute an alternative trophic link providing essential dietary nutrients that support somatic growth and reproduction of consumers. Using phytoplankton-parasites associations grown under laboratory controlled conditions we assessed the fatty acids and biochemical composition of species with different nutritional quality and followed the metabolic pathway from the algal host and their parasites zoospores using compound-specific stable isotope analysis. This study demonstrated that chytrids are trophic upgraders able to retain essential nutrients that can be transferred to upper trophic levels both in terms of organic matter quantity and nutritional quality. Through the production of zoospores, nutritionally important long-chain polyunsaturated fatty acids that can be consequently assimilated by consumers. We conclude that parasitism at the base of aquatic food webs may represent a crucial trophic link for dietary nutrients and essential biomolecules alternative to herbivory or bacterivory, which can be particularly crucial during the proliferation of inedible or nutritionally inadequate algal species fostered by climate change.

ANMCO Position paper: New perspectives on the role of n-3 polyunsaturated fatty acids in cardiovascular prevention

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the most important long-chain polyunsaturated fatty acids of the n-3 series (n-3 PUFA). Recent studies have clarified that EPA and DHA have different tissue distribution and influence target organs in a distinct way. In addition to the main effect of reducing triglycerides (TG), they exert antithrombotic, antiarrhythmic, anti-inflammatory, anti-atherogenic, and hemodynamic effects. The different action of PUFA n-3 depends on the dosage and duration of treatment: the effect on TG requires high doses and a few weeks/months of treatment.Several epidemiological studies have shown a relationship between hypertriglyceridemia and cardiovascular risk, confirmed by post-hoc analysis of statin trials and by recent genetic linkage studies. Moreover in secondary prevention, the evidence of a significant "residual risk", even in the presence of an adequate control of LDL-cholesterol, has led the scientific community to consider further intervention objectives in the context of the individual lipid profile, the most promising of which is certainly hypertriglyceridemia.The recent landmark REDUCE-IT study is the first major lipid intervention study to demonstrate a benefit deriving from an approach not based on the LDL target, focusing on a determinant factor of residual risk such as hypertriglyceridemia and treating it with high doses of n-3 PUFA (4 g/day).Overall, the "lipid residual risk" approach involves two integrated actions: (i) the achievement of the LDL-cholesterol target (<70 mg/dl) by using statins, ezetimibe, PCSK9 inhibitors; (ii) checking TG levels in order to start n-3 PUFA in case of TG values >150 mg/dl, at an initial dosage of 2-3 g/day (up to 4 g/day after 10-12 weeks).

Phospholipid Species in Newborn and 4 Month Old Infants after Consumption of Different Formulas or Breast Milk

IntroductionArachidonic acid (AA) and docosahexaenoic acid (DHA) are important long-chain polyunsaturated fatty acids for neuronal and cognitive development and are ingredients of infant formulae that are recommended but there is no evidence based minimal supplementation level available. The aim of this analysis was to investigate the effect of supplemented AA and DHA on phospholipid metabolism.MethodsPlasma samples of a randomized, double-blind infant feeding trial were used for the analyses of phospholipid species by flow-injection mass spectrometry. Healthy term infants consumed isoenergetic formulae (intervention formula with equal amounts of AA and DHA—IF, control formula without additional AA and DHA—CF) from the first month of life until the age of 120 days. A group of breast milk (BM) -fed infants was followed as a reference.ResultsThe plasma profile detected in newborns was different from 4 month old infants, irrespective of study group. Most relevant changes were seen in higher level of LPC16:1, LPC20:4, PC32:1, PC34:1 and PC36:4 and lower level of LPC18:0, LPC18:2, PC32:2, PC36:2 and several ether-linked phosphatidylcholines in newborns. The sum of all AA and DHA species at 4 month old infants in the CF group showed level of 40% (AA) and 51% (DHA) of newborns. The supplemented amount of DHA resulted in phospholipid level comparable to BM infants, but AA phospholipids were lower than in BM infants. Interestingly, relative contribution of DHA was higher in ether-linked phosphatidylcholines in CF fed infants, but IF and BM fed infants showed higher overall ether-linked phosphatidylcholines levels.ConclusionIn conclusion, we have shown that infant plasma phospholipid profile changes remarkably from newborn over time and is dependent on the dietary fatty acid composition. A supplementation of an infant formula with AA and DHA resulted in increased related phospholipid species.

Omega-3 fatty acids transport through the placenta

The placenta is a temporary vital organ for sustaining the development of the fetus throughout gestation. Although the fatty acid composition delivered to the fetus is largely determined by maternal circulating levels, the placenta preferentially transfers physiologically important long-chain polyunsaturated fatty acids (LC-PUFAs), particularly omega-3 (n-3) FAs. The precise mechanisms governing these transfers were covered in a veil, but have started to be revealed gradually. Several evidences suggest fatty acid transport proteins (FATPs), placental specific membrane bound fatty acid binding proteins (pFABPpm) and fatty acid translocases (FAT/CD36) involved in LC-PUFAs uptake. Our studies have shown that the placental transfer of omega-3 FAs through the trophoblast cells is largely contributed by fatty acid binding protein 3 (FABP3). Recently there are considerable interests in the potential for dietary omega-3 FAs as a therapeutic intervention for fetal disorders. In fact, prenatal supply of omega-3 FAs is essential for brain and retinal development. Recent findings suggest a potential opportunity of omega-3 FA interventions to decrease the incidence of type 2 diabetes in future generations. In this review, we discuss the molecular mechanism of transportation of omega-3 FAs through the placenta and how omega-3 FAs deficiency/supplementation impact on fetal development.Asian J. Med. Biol. Res. March 2016, 2(1): 1-8

Metabolic engineering of long chain-polyunsaturated fatty acid biosynthetic pathway in oleaginous fungus for dihomo-gamma linolenic acid production

Microbial lipids are promising alternative sources of long chain-polyunsaturated fatty acids (LC-PUFAs) for food, feed, nutraceutical and pharmaceutical sectors. Dihomo-γ-linolenic acid (C20:3Δ8,11,14; DGLA) is an important LC-PUFAs with anti-inflammatory and anti-proliferative effects. To generate a DGLA-producing strain, fatty acid reconstitution in Aspergillus oryzae was performed by metabolic engineering through co-expression of codon-optimized Pythium Δ6-desaturase and Δ6-elongase, which had high conversion rates of substrates to respective products as compared to the native enzymes. The Δ6-desaturated and Δ6-elongated products, γ-linolenic acid (C18:3Δ6,9,12; GLA) and DGLA, were accumulated in phospholipids rather than triacylglycerol. Interestingly, the manipulation of lipid quality in the oleaginous fungus did not affect growth and lipid phenotypes. This strategy might expand to development of the oleaginous fungal strain for producing other tailor-made oils with industrial applications.

Maternal dietary omega-3 fatty acids and placental function

The developing fetus requires substantial amounts of fatty acids to support rapid cellular growth and activity. Although the fatty acid composition delivered to the fetus is largely determined by maternal circulating levels, the placenta preferentially transfers physiologically important long-chain polyunsaturated fatty acids (LC-PUFAs), particularly omega-3 (n-3) PUFAs. Maternal dietary supplementation with n-3 PUFAs during pregnancy has been shown to increase gestation length, enhance fetal growth, and reduce the risk of pregnancy complications, although the precise mechanisms governing these effects remain uncertain. Omega-3 PUFAs are involved in several physiological pathways which could account for these effects, including anti-inflammatory, pro-resolving, and anti-oxidative pathways. Recent studies have shown that maternal dietary n-3 PUFA supplementation during rat pregnancy can reduce placental oxidative damage and increase placental levels of pro-resolving mediators, effects associated with enhanced fetal and placental growth. Because several placental disorders, such as intrauterine growth restriction, preeclampsia, and gestational diabetes mellitus, are associated with heightened placental inflammation and oxidative stress, there is considerable interest in the potential for dietary n-3 PUFAs as a therapeutic intervention for these disorders. In this study, we review the impact of dietary n-3 PUFAs on placental function, with particular focus on placental inflammation, inflammatory resolution, and oxidative stress.

Circulating Docosahexaenoic Acid Levels Are Associated with Fetal Insulin Sensitivity

BackgroundArachidonic acid (AA; C20∶4 n-6) and docosahexaenoic acid (DHA; C22∶6 n-3) are important long-chain polyunsaturated fatty acids (LC-PUFA) in maintaining pancreatic beta-cell structure and function. Newborns of gestational diabetic mothers are more susceptible to the development of type 2 diabetes in adulthood. It is not known whether low circulating AA or DHA is involved in perinatally “programming” this susceptibility. This study aimed to assess whether circulating concentrations of AA, DHA and other fatty acids are associated with fetal insulin sensitivity or beta-cell function, and whether low circulating concentrations of AA or DHA are involved in compromised fetal insulin sensitivity in gestational diabetic pregnancies.Methods and Principal FindingsIn a prospective singleton pregnancy cohort, maternal (32-35 weeks gestation) and cord plasma fatty acids were assessed in relation to surrogate indicators of fetal insulin sensitivity (cord plasma glucose-to-insulin ratio, proinsulin concentration) and beta-cell function (proinsulin-to-insulin ratio) in 108 mother-newborn pairs. Cord plasma DHA levels (in percentage of total fatty acids) were lower comparing newborns of gestational diabetic (n = 24) vs. non-diabetic pregnancies (2.9% vs. 3.5%, P = 0.01). Adjusting for gestational age at blood sampling, lower cord plasma DHA levels were associated with lower fetal insulin sensitivity (lower glucose-to-insulin ratio, r = 0.20, P = 0.036; higher proinsulin concentration, r = −0.37, P <0.0001). The associations remained after adjustment for maternal and newborn characteristics. Cord plasma saturated fatty acids C18∶0 and C20∶0 were negatively correlated with fetal insulin sensitivity, but their levels were not different between gestational diabetic and non-diabetic pregnancies. Cord plasma AA levels were not correlated with fetal insulin sensitivity.ConclusionLow circulating DHA levels are associated with compromised fetal insulin sensitivity, and may be involved in perinatally “programming” the susceptibility to type 2 diabetes in the offspring of gestational diabetic mothers.

A comparative study of fatty acids in human breast milk and breast milk substitutes in Kuwait

Specific standards of infant formula lack detailed recommendations about fatty acids in formula preparations except for linoleic acid [18:2(n-6)]. Many fatty acids were known to be very important in the development of early life. Human breast milk is considered the best model for designing breast milk substitutes with the ideal nutritive value. Fatty acid composition of human milk obtained from 19 full breast feeding Kuwaiti mothers and in 22 adapted formulas (breast milk substitutes) was determined by using capillary gas chromatographic technique. Palmitic acid (16:0), and as a consequence, total saturated fatty acids were found to be lower in human milk than formula milk. However, total mono- and polyunsaturated fatty acids were found to be higher in human milk than in formula milk. Linoleic acid [18:2(n-6)] content in formula milk was similar to human milk, while α-linolenic acid [18:3,(n-3)] showed a higher percentage in formula milk. Evidently formula milk preparations provide essential fatty acids for infants in adequate amounts as a results of their fat blend. Formula milk tends to contain lower percentages of cis- and trans-isomeric fatty acids compared to human milk. In contrast to human milk, most formulas lacked physiologically important long-chain polyunsaturated fatty acids (LCP).

Fatty acid composition of lipid classes in maternal and cord plasma at birth.

The fatty acid composition of plasma phospholipids, triglycerides, cholesterol esters and nonesterified fatty acids was determined by high-resolution capillary gas-liquid chromatography in 41 pairs of mothers and their term infants at time of birth. The total free fatty acid content in maternal and cord plasma was positively correlated, possibly reflecting a passive, gradient dependent transplacental passage of nonesterified fatty acids. Higher percentage values of several saturated and monounsaturated fatty acids in cord than in maternal plasma phospholipids, triglycerides and nonesterified fatty acids may have resulted from an active fetal fatty acid synthesis. Trans fatty acids were found in every lipid class at similar or slightly lower percentages in neonatal as in maternal plasma, thus confirming their placental passage. Long-chain n-6 and n-3 polyunsaturated fatty acids are preferentially incorporated into phospholipids and sterolesters of both maternal and cord plasma. Linoleic and alpha-linolenic acids were found in smaller portions in cord than in maternal fatty acids, in contrast to strikingly higher proportions of their long-chain polyunsaturated metabolites, which may indicate a discriminating placental transport for certain physiologically important long-chain polyunsaturated fatty acids. The fetus appears to obtain fatty acids from a combination of de novo synthesis, a passive gradient dependent transplacental passage of nonesterified fatty acids and a selective materno-fetal placental transport for certain fatty acids, such as physiologically important long-chain polyunsaturated fatty acids.

Fat content and fatty acid composition of infant formulas.

Fat content and fatty acid composition of 25 commercial infant formulas sold in the Federal Republic of Germany and of 3 home-made milk formulas were analysed, using gravimetry of extracted lipids and high-resolution capillary gas-chromatography. Results were compared with the composition of human milk. Fat contents of all commercial formulas were similar to human milk values and met current recommendations, but 2 home-made preparations were at the upper and lower limits of the recommended range. Milk formulas tended to contain higher percentages of saturated and lower ones of cis-monounsaturated and trans-isomeric fatty acids than human milk. Linoleic acid (C18:2n-6) content was similar to human milk in most products but deviated clearly from recommended values in 2 home-made mixtures. Alpha-linolenic acid (C18:3n-3) values were often low in formulas, resulting a high n-6/n-3-ratios. In contrast to human milk, all formulas contained only minor amounts of the physiologically important long-chain polyunsaturated fatty acids with 20 and 22 carbon atoms. Some seasonal variation in the content of palmitic (C16:0), oleic (C18:1n-9), linoleic and trans-fatty acids was found when five arbitrarily selected adapted formulas were analysed repeatedly over one year. The composition of a home-made formula made from fresh cow's milk was markedly different in winter and in summer, when percentages of saturated and trans-fatty acids were higher and of linoleic acid were lower. We conclude that the composition of most commercial formulas is better suited to meet the lipid requirements of young infants than the home-made preparations investigated.(ABSTRACT TRUNCATED AT 250 WORDS)