Docosahexaenoic acid Omega-3 fatty acid

There is evidence that the level of an omega-3 fatty acid (docosahexaenoic acid) is low in the tissues of subjects who exhibit violent behaviour. Supplementation with this fatty acid has been shown to reduce aggression in a normal population of university students. 

Lim GP, Calon F, Morihara T, Yang F, Teter B, Ubeda O, Salem N Jr, Frautschy SA, Cole GM. A diet enriched with the omega-3 fatty acid docosahexaenoic acid reduces amyloid burden in an aged Alzheimer mouse model. J. Neurosci. 2005 25 3032-3040. Hashimoto M, Hossain S, Shimada T, Shido O. Docosahexaenoic acid-induced protective effect against impaired learning in amyloid beta-infused rats is associated with increased synaptosomal membrane fluidity. Clin. Exp. Pharmacol. Physiol. 2006 33 934-939. 

Oil from fish such as tuna and salmon is a good source of omega-3 fatty adds, including the C22 omega-3 fatty acid docosahexaenoic acid [DHA, whose full lUPAC name is (4Z, 7Z,10Z,13Z,16Z,19Z)-4,7,10,13,16,19-docosahexaenoic acid]. DHA is also found in breast milk, gray matter of the brain, and retinal tissue. 

Sijtsma, L. and de Swaaf, M.E. 2004. Biotechnological production and applications of the omega-3 polyunsaturated fatty acid docosahexaenoic acid. Appl. Microbiol. BiotechnoL 64, 146-153. 

Massaro M., Habib A., Lubrano L., Del Turco S., Lazzerini G., Bourcier T., Weksler B. B., and De Caterina R. (2006). The omega-3 fatty acid docosahexaenoate attenuates endothelial cyclooxygenase-2 induction through both NADP(H) oxidase and PKCe inhibition. Proc. Natl. Acad. Sci. USA 103 15184-15189. 

It has been postulated that increased consmnption of oily fish, rich in omega-3 fatty acids (eicosapentaenoic acid and docosahexaenoic acid) which... 

Pereira, S.L., Leonard, A.E., Huang, Y.S., Chuang, L.T., and Mukeiji, P. 2004. Identification of two novel microalgal enzymes involved in the conversion of the omega-3-fatty acid, eicosapentaenoic acid, into docosahexaenoic acid. Biochem. J. 384, 357-366. 

Speaking of food that is good for the body, scientists have also found an acid (called docosahexaenoic acid, or DHA) present in fish that they believe plays a very important role in the way the brain functions. DHA is an omega-3 fatty acid. About 60% of the human brain is made up of fat, and most of that appears to be DHA fat. 

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are omega-3 polyunsaturated fatty acids that are most abundant in fatty fish such as sardines, salmon, and mackerel. A diet high in EPA plus DHA or supplementation with these fish oils reduces the risk of cardiovascular mortality, reinfarction, and stroke in patients who have experienced an MI. 

Human milk is rich in essential fatty acids of both the omega-3 and omega-6 families. This suggests that the activity of the A -desaturase may be too low in the infant to provide a sufficient amount of these fatty acids for development of tissues, particularly the brain and retina. It has been shown that development of visual acuity in infants is dependent upon the presence of docosahexaenoic acid in mother s milk. Hence, it is recommended that breastfeeding should be carried out for as long as 12 months after birth. These fatty acids are now added to commercial infant feeds (Chapter 15, Table 15.8). 

There is some evidence that, in these patients, the interconversion between the polyunsaturated fatty acids is disturbed, which restricts the formation of eicosapentaenoic and docosahexaenoic acids. Such children are less likely to have been breastfed (breast milk contains these omega-3 fatty acids) they are more likely to suffer from allergies associated with essential fatty acid deficiency and also dry skin and hair and the membranes of the erythrocytes contain less omega-3 fatty acids compared with normal children. So far, the results of supplementation of the diet of these children with this disorder have not been conclusive. 

Several methods have been proposed to produce polyunsaturated fatty acid (PUFA) concentrates particularly high in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Most PUFA enrichment methods are based upon a combination of techniques such as saponification, solvent extraction, urea fractionation, molecular distillation, fractionation distillation, liquid chromatography, and super critical carbondioxide extraction. Current evidence suggests that the physiological effects of omega-3 fatty acids are such that the annual world supply of fish oils will be grossly inadequate as a source of these materials, and alternative sources will be needed (Belarbi et al, 2000). 

Omega-3 fatty acids are long-chain polyunsaturated fatty acids. The parent fatty acid of this group is alpha-linolenic acid, an essential fatty acid that the body is unable to synthesize alpha-linolenic acid can be converted in the body to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In animals and man, these acids reduce the production of several compounds that are involved in inflammation and thrombosis, such as eicosanoids (prostaglandins, thromboxanes, prostacyclin, and leukotrienes) and cytokines (interleukin II-l) (1). The extent of the conversion of alpha-linolenic acid to EPA and DHA is unclear. The conversion process appears to be inhibited by a high intake of linoleic acid, another essential fatty acid (2). In addition, alpha-linolenic acid is found in dark green vegetables and the oils of certain nuts and seeds, especially rape seeds and soya beans. 

Supercritical fluid carbon dioxide (SC-CO2) fractionation of fish oil ethyl esters (EE) was employed to prepare EE of two omega-3 fatty acids, all cis-5,8,11,14, 17-eicosapentaenoic acid (EPA) and all cis-4,7,10,13, 16,19-docosahexaenoic acid (DHA) in 90% purity and to separate the synthetic triacylglycerols (TG), trieicosapentaenoylglycerol (tri-EPA), and tridocosahexaenoyl-glycerol (tri-DHA) in > 92% purity from other reaction mixture components. In the synthesis, glycerine reacted with EE and sodium glyceroxide catalyst to form TG. 

Kyle, D. (2001) The large-scale production and use of a single-cell oil highly enriched in docosahexaenoic acid. In Omega-3 Fatty Acids Chemistry, Nutrition and Health Effects. (Shahidi, F. and Finley, J.W., eds.) Washington, D.C. American Chemical Society, Oxford University Press, pp. 92-107. 

Omega-3 PUFAs are essential unsaturated fatty acids obtained from food sources or from supplements. Amongst nutritionally important polyunsaturated n-3 fatty acids, a-linolcnic acid (ALA), eicosapentae-noic acid (EPA), and docosahexaenoic acid (DHA) are highly concentrated in the brain and have antioxidative stress, anti-inflammatory and antiapoptotic effects. The exposure to n-3 fatty acids enhances adult hippocampal neurogenesis associated with cognitive and behavioral processes, promotes synaptic plasticity by increasing longterm potentiation, and modulates synaptic protein expression to stimulate the dendritic arborization and new spine formation [496]. 

One important group of nutrients, rarely included in the Western diet, is the essential fatty acids. These compounds are precursors to prostaglandins, which inhibit testosterone binding in the prostate. They also act as anti-inflammatory agents and restrain protein synthesis and cell growth in the prostate. The omega-3 marine lipids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been shown to inhibit the growth of prostatic tumors. Flax seed, a rich source of essential fatty acids, has been shown to inhibit cancer metastasis in studies done with mice. 

Kafawy O, Zerouga M, Stillwell W, Jenski LJ. Docosahexaenoic acid in phosphatidylchohne mediates cytotoxicity more effectively than other omega-3 and omega-6 fatty acids. Cancer Lett 1998 132 23-29. 

Alpha-linolenic acid (LNA or 18 3n-3) An 18-carbon, three double-bond fatty acid in the omega-3 family. This polyunsaturated fatty acid is produced in the chloroplast of terrestrial and marine plants. In animals, alpha-linolenic acid is metabolized into the longer-chain omega-3 fatty acids, eicosapentaenoic acid, and docosahexaenoic acid. 

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