Fatty acid dietary

Degradation of Dietary Fatty Acids Occurs Primarily in the Duodenum... 

O Farrell, S. (1994). Dietary fatty acids and tissue damage. PhD Thesis, University of Liverpool. 

FIGURE 3-7 Pathways for the interconversion of brain fatty acids. Palmitic acid (16 0) is the main end product of brain fatty acid synthesis. It may then be elongated, desaturated, and/or P-oxidized to form different long chain fatty acids. The monoenes (18 1 A7, 18 1 A9, 24 1 A15) are the main unsaturated fatty acids formed de novo by A9 desaturation and chain elongation. As shown, the very long chain fatty acids are a-oxidized to form a-hydroxy and odd numbered fatty acids. The polyunsaturated fatty acids are formed mainly from exogenous dietary fatty acids, such as linoleic (18 2, n-6) and a-linoleic (18 2, n-3) acids by chain elongation and desaturation at A5 and A6, as shown. A A4 desaturase has also been proposed, but its existence has been questioned. Instead, it has been shown that unsaturation at the A4 position is effected by retroconversion i.e. A6 unsaturation in the endoplasmic reticulum, followed by one cycle of P-oxidation (-C2) in peroxisomes [11], This is illustrated in the biosynthesis of DHA (22 6, n-3) above. In severe essential fatty acid deficiency, the abnormal polyenes, such as 20 3, n-9 are also synthesized de novo to substitute for the normal polyunsaturated acids. 

Adrenoleukodystrophy is an X-linked dysmyelinative disorder caused by mutations in the ABCD1 gene, which encodes the peroxisomal integral membrane ALD protein, a member of the ATP binding cassette transporter family. These mutations result in impaired clearance of plasma very-long-chain fatty acids. Affected males may present with symmetrical distal axonal polyneuropathy, adrenocortical insufficiency or CNS demyelination, while occasional heterozygous women demonstrate deficits suggestive of multiple sclerosis [56]. Manipulation of dietary fatty acid intake has some minimal therapeutic effect, while bone marrow transplantation has diminished deficits in a few patients. (See in Ch. 41.)... 

Figure 6.15 (a) Metabolic modification of endogenously synthesized fatty acids, (b) Metabolic modification of essential dietary fatty acids... 

Most of our fat intake will consist of fatty acids with an even number of carbon atoms, but not all dietary fatty acids nor all those synthesized in the liver are saturated. A variable, but probably not inconsiderable, proportion of dietary fatty acids are unsaturated, partly perhaps because a high intake of unsaturated fat is recommended to help reduce the risk for diseases of the heart and vascular system. Unsaturated and odd-numbered fatty acids pose particular chemical problems to the 3-oxidation pathway and additional enzymes are required for their metabolism. 

However, similar changes in hpid conposition are possible using a variety of other cell types (Bums and Wagner, 1993) such as an adenocarcinoma (Awad and Specter, 1976), and hepatoma (Wood et al, 1975). The dietary fatty acid modification is not limited to tumor cells, since many tissues of the host are affected (Bums et al., 1983). However, different tissues are modified to varying extents, and because of this it will likely be possible to develop protocols that provide therapeuhc selechvity by producing greater or lesser enrichment of the neoplashc cells with a particular type of fatty acid as compared to normal tissues. We have also demonstrated that L1210 leukemia cells that were fatty acid modified in vivo and then placed into tissue culture maintain their experimentally-induced fatty acid composition for up to 4 days (Bums et al, 1980). Therefore, this is a versahle model. 

Harbige, L. S., and Fisher, B. A. (2001). Dietary fatty acid modulation of mucosaUy-induced tolerogenic immune responses. Proc. Nutr. Soc. 60,449 56. 

CN164 Arechaga, G., I. Prieto, A. B. Segarra, et al. Dietary fatty acid composition affects aminopeptidase activities in the testes of mice. Int J Androl 2002 25(2) 113-118. 

CN177 Wallace, F. A., E. A. Miles, and P. C. Calder. Activation state alters the effect of dietary fatty acids on pro-inflammatory mediator production by murine macrophages. Cytokine 2000 12(9) 1374-1379. 

CN198 Prieto, R. M., W. Stremmel, C. Sales, and J. A. Tur. Effect of dietary fatty acids on jejunal and ileal oleic acid uptake by rat brush border membrane vesicles. Eur J Med Res 1996 1(7) 355-360. 

F. Belch, and R. D. Sturrock. The therapeutic affects of dietary fatty acid supplementation in the autoimmune disease of the MRL-MP-IPR mouse. 

Kremer, J.M., Michalek, A.V., Lininger, L., Huyck, C., Bigauoette, J., Timchalk, M.A., Rynes, R.I., Zieminski, J., Bartholomew, L.E. (1985). Effects of manipulation of dietary fatty-acids on clinical manifestations of rheumatoid-arthritis. Lancet, 325, 184-187. 

The carcinogenicity of af la toxin is reduced by protein deficiency, presumably because of reduced metabolic activation to the epoxide intermediate, which may be the ultimate carcinogen, which binds to DNA (Fig. 5.14). A deficiency in dietary fatty acids also decreases the activity of the microsomal enzymes. Thus, ethylmorphine, hexobarbital, and aniline metabolism are decreased, possibly because lipid is required for cytochromes P-450. Thus, a deficiency of essential fatty acids leads to a decline in both cytochromes P-450 levels and activity in vivo. 

Fang, J.-L., Vaca, C.E., Valsta, L.M. Mutanen. M. (1996) Determination of DNA adducts of malonaldehyde in humans effects of dietary fatty acid composition. Carcinogenesis, 17, 1035-1040... 

The usual diet of ruminants consists of fresh and preserved herbage and cereals. As a result of microbial activity in the rumen, esterified dietary fatty acids are hydrolyzed, short chain fatty acids are produced by fermentation of cellulose and other polysaccharides, unsaturated fatty acids are hydrogenated and/or converted to geometric (trans) and positional isomers, and microbial lipids are synthesized. These activities account in part for the enormous diversity of fatty acids in milk and the unique features short-chain and a high proportion of long chain saturated fatty acids. (Patton and Jensen, 1976 Christie, 1979B). 

Theodoratou E, McNeill G, Cetnarskyj R, Farrington SM, Tenesa A, Barnetson R, Porteous M, Dunlop M, Campbell H. 2007. Dietary fatty acids and colorectal cancer A case-control study. Am J Epidemiol 166 181-195. 

Data on the proportions of different fatty acids in plasma lipid esters (cholesteryl esters, phospholipids, free fatty acids, or triacylglycerol), erythrocyte membranes, or adipose tissue may provide a more objective and accurate path to evaluating dietary fatty acid composition (Arab, 2003 Baylin and Campos, 2006). The fatty acid composition in blood and body tissues reflects the fatty acid composition of the diet at different time points after ingestion. Short and medium-term changes in the composition of dietary fatty acid intake are reflected in plasma lipids and erythrocyte membranes, weeks and months after intake, respectively. The incorporation of fatty acids in adipose tissue reflects long-term changes in the diet (years) (Baylin and Campos, 2006 Katan et al., 1997 Ma et al., 1995 Zock et al, 1997). 

Katan, M. B., Deslypere, J. P., van Birgelen, A. P., Penders, M., and Zegwaard, M. (1997). Kinetics of the incorporation of dietary fatty acids into serum cholesteryl esters, erythrocyte membranes, and adipose tissue An 18-month controlled study. J. Lipid Res. 38, 2012-2022. 

Saadatian-Elahi, M., Norat, T., and Goudable, J. 2004. Biomarkers of dietary fatty acid intake and the risk of breast cancer A meta-analysis. Int. J. Cancer 111, 584-591. 

Brenner, R.R., Vazza, D.V. and De Tomas, M.E. (1963). Effect of a fat-free diet and of different dietary fatty acids (palmitate, oleate and linoleate) on the fatty composition of freshwater fish lipids. Journal of Lipid Research 4,341-345. 

Owen, J.M., Adron, J.W., Middleton, C. and Cowey, C.B. (1975). Elongation and desaturation of dietary fatty acids in turbot Scophthalmus maximus L. and rainbow trout, Salmo gairdnerii Rich. Lipids 10,528-531. 

Atteh, J.O. and Leeson, S. (1983) Effects of dietary fatty acids and calcium levels on performance and mineral metabolism of broiler chickens. Poultry Science 62, 2412-2419. 

PPARs are activated by a wide range of molecules including the fibrate hypolipidemic drugs and a range of saturated and unsaturated dietary fatty acids, eicosanoids and prostanoids.120,121 Recently, triterpenoids such as ursolic and oleanolic have also been reported to stimulate the alpha receptor122 and increase filaggrin biosynthesis. 

Okuyama, H., Kobayashi, T., and Watanabe, S., Dietary fatty acids — the N-6/N-3 balance and chronic elderly diseases. Excess linoleic acid and relative N-3 deficiency syndrome seen in Japan, Prog. Lipid Res., 35, 409, 1996. 

Murphy, M.G., Dietary fatty acids and membrane protein function, J. Nutr. Biochem., 1, 68, 1990. 

Burton, J.L., Dietary fatty acids and inflammatory skin disease, Lancet, i, 27,1989. 

Calder, P.C. 1998. Dietary fatty acids and the immune system. NutrRev 56(1) Part II S70-S83. 

Frank, C.L. (1992). The influence of dietary fatty acids on hibernation by golden-mantled ground squirrels (Spermophilus lateralis). Physiol. Zool. 65 906-920. 

Belch, J.J.F., Ansell, D., Madhock, R., O Dowd, A. and Sturrock, R.D. (1988) Effects of altering essential dietary fatty acids on requirements for non-steroidal anti-inflammatory drugs in patients with rheumatoid arthritis a double blind placebo controlled study. Ann. Rheum. Dis., 47, 404-405. 

Incorporation of dietary unsaturated fat into milk fat by ruminants is low because of the efficient ruminal biohydrogenation process (Jenkins, 1993). Nevertheless, dietary fatty acids have profound effects on milk fat composition that have led to a prodigious amount of literature in the past 20 years (for reviews see Sutton, 1989 Grummer, 1991 Palmquist et al., 1993 Kennedy, 1996 Mansbridge and Blake, 1997 Chilliard et al., 2000, 2001). 

Kelly, M.L., Berry, J.R., Dwyer, D.A., Griinari, J.M., Chouinard, P.Y., Van Amburgh, M.E., Bauman, D.E. 1998a. Dietary fatty acid sources affect conjugated linoleic acid concentrations in milk from lactating dairy cows. J. Nutr. 128, 881-885. 

Mensink, R.P., Zock, P.L., Kester, A.D.M., Katan, M.B. 2003. Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins a meta-analysis of 60 controlled trials. Am. J. Clin. Nutr. 77, 1146-1155. 

Figure 23-2. Metabolism in the fed state. An adequate supply of carbohydrate provides glucose to replenish glycogen stores. Dietary protein provides amino acids for protein synthesis. Dietary carbohydrates, fats, and proteins can all be metabolized to generate ATP. (For clarity, ATP generation during P-oxidation of fatty acids and substrate-level phosphorylation during glycolysis is not depicted.) Excess dietary carbohydrates and amino acids are converted to fatty acids and, along with excess dietary fatty acids, stored as triacylglycerols. DHAP, dihydroxyacetone phosphate.

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