Essential fatty acids, pregnancy, and pregnancy outcome : relationship between mother and child
Year: 1994
Type: dissertation
Abstract: Since men, in contrast to plants, lack A-12-and A-15-desaturase, they cannot synthesize the fatty acids linoleic acid (18:2(n-6)O , LA) and a-linolenic acid (18:3(n-3), LnA) <fe novo.Therefore, LA and LnA must be derived from the diet (3).Once in the body, these parent EFAs can be desaturated and elongated to longer chain, more unsaturated derived EFAs of the (n-6) and (n-3) family, respectively (see figure 1 ).For the synthesis of long chain polyenes (polyunsaturated fatty acid with 20 or more carbon atoms and at least one more double bond than their parent essential fatty acid, LCPs), the activity of A-6-desaturase is rate limiting.The substrate affinity of this enzyme is in the order 18:3(n-3)>18:2(n-6)>18:l(n-9).In addition, the activity of A-6 desaturation is influenced by the concentration of the reaction substrate as well as product.This latter also applies to the A-5-desaturase activity (4,5).In mammals, there is no interconversion between the fatty acids of the different families.Fatty acids of the (n-3) and (n-6) family are found especially in membrane phospholipids, where they serve important functions.Linoleic acid is essential in maintaining the epidermal water barrier (6,7).In addition, LA is the precursor of dihomo-y-linolenic acid (20:3(n-6), DHGL) and arachidonic acid (20:4(n-6), AA), which are substrates for the production of the eicosanoids of the 1 -and 2-series, respectively (8,9).AA is also an important structural fatty acid in the brain (10,11).Evidence for a specific function for 18:3(n-3) other than being a precursor of (n-3) long chain polyenes has not yet been reported (12).The most important fatty acids derived from LnA are timnodonic acid (20:5(n-3), TA) and cervonic acid (22:6(n-3),• " The nomenclature used for fatty acids is as follows: the number of carbon atoms, followed by a colon and the number of double bonds: between brackets the fatty acid family is indicated by designation of the position of the first double bond from the methyl end of the carbon chain.Biochemical EFA status of mothers and their neonates after normal pregnancy
Author: M.D.M. Al
Language: English
Subfield: Nutrition and Dietetics
Field: Nursing
Domain: Health Sciences
Open Access status: gold
OpenAlex ID: W1592652020