Docosapentaenoic acid

Docosahexaenoic acid (DHA), 17 663, 665 Docosanoic acid, physical properties, 5 30t 4,8,12,15,19-Docosapentaenoic acid physical properties, 5 33t cis-ll-Docosenoic acid, physical properties, 5 3 It... 

Anderson GJ, Connor WE, Corliss JD (1990) Docosahexaenoic acid is the preferred dietary o>-3 fatty acid for the development of the brain and retina. Pediatr Res 27 89-97 Assies J, Lieverse R, Vreken P, Wanders RJA, Dingemans PMJA, Linszen DH (2001) Significantly reduced docosahexaenoic and docosapentaenoic acid concentrations in erythrocyte membranes form schizophrenic patients compared with a carefully matched control group. Biol Psychiatr 45 510-522... 

Litchfield, C. (1968) Predicting the positional distribution of docosahexaenoic and docosapentaenoic acids in aquatic animal triglycerides. Lipids, 3, 417-419. 

Values are given as means SEM. NR, Not Reported. AA, Arachidonic acid EPA, Eicosapentaenoic acid DPA, Docosapentaenoic acid DHA, Docoshexaenoic acid. Data are taken from J. Dyerberg and H. O. Bang, Lancet, II, 433-43S (1979). 

The essential fatty acids are also converted in the body to the 22-carbon fatty acids docosapentaenoic acid (DPA)and docosahexaenoic acid (DHA). DPAis made from linoleic acid DHA is made from linolenic acid.The functions of these 22-carb-on fatty acids are not clear, but they may be important for vision and for other functions of the nervous system. DPA and DHA can be further elongated, in the body, to the "very-long-chain fatty acids." The very-long-chain fatty adds contain 24 to 34 carbons, and occur in the brain, rods of the retina, and in the testes (Sixh et al., 1996). Their functions are not clear. 

On the other hand, from Thraustochytrium sp., a unicellular marine eukaryotic microorganism, which can produce substantial amounts of long chain polyunsaturated FA such as DHA and docosapentaenoic acid (22 5 DPA), two cDNAs encoding for two... 

A defect in the capability of the enzyme 5-6-desaturase to convert linoleic acid to y-linolenic acid is known to occur in patients with atopic dermatitis (9). Patients with atopic eczema have a dietary deficiency in metabolites of linoleic y-linolenic acid, dihomo-y-linolenic acid, arachidonic acid, adrenic acid, and docosapentaenoic acid caused by a reduced rate of activity in the 5-6-desturase enzyme (8). Galli et al. compared blood samples from babies born to parents who suffered from atopic eczema. Results showed... 

Sprecher and colleagues (Voss et al., 1991) established that the metabolism of docosapentaenoic acid (DPA), (22 5n-3) to DHA in liver is independent of a 4-desaturase (see Figure 10.2). This latter pathway involves the microsomal chain elongation of 22 5n-3 to 24 5n-3, followed by its desaturation to 24 6n-3 and conversion to DHA via a peroxisomal retroconversion of tetracosahexaenoic acid (24 6n-3). The conversion efficiency of LNA to DHA is limited in human adults, with conversion efficiencies estimated to be approximately 3.8% (Emken et al.,... 

FIG. 1 Metabolism of n-3, n-6, and n-9 fatty acids and their conversion to various eicosanoids. AA, arachidonic acid COX, cyclooxygenase DGLA, dihomo-gamma-linolenic acid DHA, docosahexaenoic acid DPA, docosapentaenoic acid EPA, eicosapentaenoic acid HETE, hydroxyeicosatetraenoic acid LOX, lipoxygenase LT, leukotriene TX, thromboxane. 

LA, linoleic acid LNA, linolenic acid AA, arachidonic acid EPA, eicosapentaenoic acid DTA, docosatetranoic acid DPA, docosapentaenoic acid DHA, docosahexaenoic acid. 

Pawlosky RJ. Salem N Jr. Ethanol exposure causes a decrease in docosahexaenoic acid and an increase in docosapentaenoic acid in feline brains and retinas. Am J Clin Nutr 1995 61 1284—1289. 

Voss A, Reinhart M, Sankarappa S, Sprecher H. The metabolism of 7,10,13,16,19-docosapentaenoic acid to 4,7,10,13,16,19-docosahexaenoic acid inrat liveris independent of a4-desaturase. J Biol Chem 1991 266 19,995-20,000. 

There are clear abnormalities of fatty acid concentrations in depression that are distinct from those in schizophrenia (Adams, Lawson, Sanigorski, Sinclair, 1996 Maes et al., 1996 Maes et al., 1999 Peet, Murphy, Shay, Horrobin, 1998 Edwards, Peet, Shay, Horrobin, 1998). Eirst, the abnormalities are present in both plasma and in red cells, raising the possibility that the problem may be in fatty acid metabolism in general, rather than membrane phospholipid metabolism in particular. Second, the abnormalities are specifically deficits in the omega-3 fatty acids EPA, DHA, and docosapentaenoic acid (DPA), and particularly in EPA. In contrast to the situation in schizophrenia, AA levels are either normal or elevated. 

Fig. 2. Biosynthetic pathways for the n-6 and n-3 families of fatty acids. Fatty acids are shown with the number of carbon atoms, followed by the number of double bonds with the positions of the double bonds in parentheses. LA, linoleic acid GLA, y-linolenic acid DGLA, dihomogamma linolenic acid ARA, arachidonic acid LNA, linolenic acid EPA, eicosapentaenoic acid DHA, docosapentaenoic acid.

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