Omega-6 fatty acid synthesis

The biosynthesis of prostaglandins of the 2 series begins with a C20 polyenoic acid, arachidonic acid, an omega-6 fatty acid. (Synthesis of prostaglandins of the 1 series begins... 

Omega-3 fatty acids and increased prostacyclin synthesis. 

Deficiency of essential amino acid precursors in the diet can cause a dysregulation of neurotransmitter activity (e.g, L-tryptophan deficiency causes a decrease in 5-HT and melatonin synthesis and activity). Deficiency in essential fatty acids (e.g, omega-3 fatty acids) can cause a dysregulation of neurottansmitter... 

Prostaglandins are a subgroup of a larger family of compounds known collectively as eicosanoids, which are synthesized from arachidonic acid (arachidonate) this is a 20-carbon omega-6 unsaturated fatty acid (C20 4). The source of the arachidonic acid for PG synthesis is the cell membrane. Most membrane phospholipids have an unsaturated fatty acid as arachidonate at carbon 2 on the glycerol backbone to help maintain membrane fluidity. The arachidonic acid released from the membrane by the... 

The key substrate for synthesis of the eicosanoids is the omega-6,20-carbon fatty acid arachidonic acid ... 

In view of these factors, it has been suggested that a deficiency of omega-3 fatty acid in the diet will decrease the concentration of these fatty acids available for synthesis of the required phospholipids in the body, including the brain. If this was a chronic deficiency it could increase the risk of development of some disorders, including depression, schizophrenia and attention deficit syndrome. There is some evidence that this is the case. 

Figure 12-5 Series 1 prostaglandin synthesis pathway. In this scheme delta-5-desaturase plays a key role in producing arachi-donic acid, but its preferred substrate is omega-3 fatty acid. Compare with Figure 12-6. (From http //www.asthmaworld.org/ OMEGA3.htm)...

Linoleic acid and the family of fatty acids derived from it are called the omega-6 fatty acids (Figure 9.96). This is because the number of carbons from the methyl end to the first double bond is six. Linoleic acid is used to make arachidonic acid (20 4co6), a fatty acid essential for the synthesis of various hormones. These hormones are the prostaglandins, thromboxanes, and leukotrienes. These three classes... 

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. 

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. 

Sohal PS, Baracos VE. Clandinin MT. Dietary omega 3 fatty acid alters prostaglandin synthesis, glucose transport and protein turnover in skeletal muscle of healthy and diabetic rats. Biochem J 1992 286 405 11. 

Li, Z.Y, and Ward, O.P. 1994. Synthesis of monoglyceride containing omega-3 fatty acids by microbial lipase in organic solvent. J. Ind. Microbiol. 13 49-52. 

Neuronal membranes contain phospholipids. A lack of essential fatty acids, such as omega-3 fats, or excessive intake of saturated fats, margarine, cholesterol, and animal fatty acids, can result in abnormalities. The neuronal cell membrane regulates the passage of molecules into and out of the cell. Neuronal membrane fluidity is believed to impact behavior, mood, and mental function. Physical properties, including the fluidity, of neuronal membranes affect neurotransmitter synthesis, signal transmission, uptake of serotonin and other neurotransmitters, neurotransmitter binding, and the activity of key enzymes that break down neurotransmitters like serotonin, epinephrine, dopamine, and norepinephrine. 

Bazan NG (2005) Neuroprotectin Di (NPDi) a DHA-derived mediator that protects brain and retina against cell injury-induced oxidative stress. Brain Pathol 15 159-166 Bazan NG (2006) The onset of brain injury and neurodegeneration triggers the synthesis of docosanoid neuroprotective signahng. Cell Mol Neurobiol 26 901-913 Bazan NG (2007) Omega-3 fatty acids, pro-inflammatory signaling and neuroprotection. CurrOpin Clin Nutr Metab Care 10 136-141... 

Sohal, P.S., Baracos, VF., and Clandinin, M.T. (1992) Dietary Omega 3 Fatty Acid Alters Prostaglandin Synthesis, Glucose Transport and Protein Ihrnover in Skeletal Muscle of Healthy and Diabetic Rats, Biochem. J. 286.405-411. 

Honda Malca S, Scheps D, KUhnel L, Venegas-Venegas E, Seifert A, Nestl BM, Hauer B (2012) Bacterial CYP153A monooxygenases for the synthesis of omega-hydroxylated fatty acids. Chem Commun (Camb) 48 5115-5117... 

Illingworth R, Harris WS, Connor WE (1984) Inhibition of low density Upoprotein synthesis by dietary omega-3 fatty acids in humans. Arteriosclerosis 4 270... 

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