Unsaturated fatty acids roles

McPhail, L.C., Clayton, C.L. and Snyderman, R (1984). A potential messenger role for unsaturated fatty acids activation of Ca -dependent protein kinase. Science 224, 622-625. 

In the last decade numerous studies were dedicated to the study of biological role of nonenzymatic free radical oxidation of unsaturated fatty acids into isoprostanes. This task is exclusively difficult due to a huge number of these compounds (maybe many hundreds). Therefore, unfortunately, the study of several isoprostanes is not enough to make final conclusions even about their major functions. F2-isoprostanes were formed in plasma and LDL after the treatment with peroxyl radicals [98], It is interesting that their formation was observed only after endogenous ascorbate and ubiquinone-10 were exhausted, despite the presence of other antioxidants such as urate or a-tocopherol. LDL oxidation was followed by... 

Saturated fatty acids do not contain double bonds in the hydrocarbon chain. Unsaturated fatty acids contain from one to hve double bonds. Those with one double bond are known as monounsaturated, those with two as diunsatu-rated and those with more than two as polyunsaturated fatty acids. A brief summary of the roles of saturated and unsaturated fatty acids is given in Table 11.1. The proportion of these fatty acids in triacylglycerol in human adipose tissue is presented in Table 11.2. 

Oleamide, an unsaturated fatty acid amide, which can modulate central nervous system fiinctions, was isolated from the cerebrospinal fluid of sleep deprived cats. Nanogram amounts of oleamide in biological fluids (using GC/MS) were measured. This quantitative assay may help determine the role of oleamide in additional physiological processes. 

General physiological roles for fatty acids in cellular lipids are caloric storage, membrane fluidity, and prostaglandin precursors. The first of these mainly involved the formation and hydrolysis of triacyl glycerols, transport and activation of non-esterified fatty acids, and other steps leading to energy conversion (110). The second role primarily involves activation and incorporation into 1- and 2- positions of different phospholipids which form a major part of membranes. The third role is linked to the requirement for certain unsaturated fatty acids in the diets of most animals (110). 

Ensenauer R, He M, Willard JM, et al (2005) Human acyl-CoA dehydrogenase-9 plays a novel role in the mitochondrial beta-oxidation of unsaturated fatty acids. J Biol Chem 280 32309-32316... 

In cereals the role of unsaturated fatty acids in cold acclimation has been demonstrated using a chemical (BASF 13-338) that reduces the linolenic acid content in polar lipids (St John et al., 1979). 

Primary amides of unsaturated fatty acids have been characterized in humans and other mammals, and although their biological role is not fully understood, they may represent a group of important signalling molecules. Oleamide, the simple amide of oleic acid, has been shown to be a sleep-inducing lipid, and the amide of erucic acid, eru-camide, stimulates the growth of blood vessels. 

Similar to Scd2 in mice (Kaestner et al., 1989), desatl mRNA is found at higher levels in brain. The role of the desaturase in brain is to supply unsaturated fatty acids necessary for the synthesis of membrane phospholipids, particularly for myelination. 

Experimental 1 T, dietary fats, both quantity and quality, play important roles in the genesis of cancers of many organs (18,19). Earlier, we demonstrated that a high fat CD diet is a more efficient liver tumor promoter than the diet with a low fat content (5). The proportion of saturated and polyunsaturated fatty acids in a CD diet is an important determining factor for the severity of the diet-induced fatty liver (20,21). Saturated fatty acids containing 14 to 18 carbons in the diet appeared to increase the deposition of fat in the liver more so than unsaturated fatty acids (22). It became of considerable interest to determine whether and how changing the quality of fat in a CD diet modifies the promoting efficacy of the diet. 

Coffee oil contains about 47% linoleic, 8% oleic, 1% hexa-decenoic, 32% palmitic, 8% stearic, and 5% behenic and longer chain fatty acids (64). As linoleic acid is the major unsaturated fatty acid in coffee oil, its major oxidation products 2,4-alkadienals and hexen-1,6-dial would play a major role in... 

---