Formula α-linolenic (18:3 ( n−3)) and linoleic (18:2( n−6)) acid influence neonatal piglet liver and brain saturated fatty acids, as well as docosahexaenoic acid (22:6 ( n−3))

Abstract

Saturated fatty acids can be synthesized de novo and play a role in determining properties of structural membranes. The effect of dietary essential fatty acids, linoleic acid (18:2 ( n−6)) and α-linolenic acid (18:3 ( n−3)), on the saturated fatty acid content of membrane phospholipid has not previously been considered in newborn nutrition. The studies report the effect of low (1% fatty acids) or high (4%) formula 18:3 ( n−3) with low (16%) or high (30–35%) formula 18:2 ( n−6) on the saturated and unsaturated fatty acid composition of liver and brain structural lipid of piglets fed formula from birth for 15 days. A significant inverse relationship between the formula % 18:3 ( n−3), but not 18:2 ( n−6), and the liver phospholipid palmitic acid (16:0) was found. This may indicate a possible effect of dietary 18:3 ( n−3) on de novo synthesis of 16:0 and requires further investigation. Monounsaturated fatty acids in both liver and brain were significantly lower in response to high 18:3 ( n−3) and to high 18:2 ( n−6) plus low 18:1 ( n−9) in the formula. Liver phospholipid and brain total lipid % docosahexaenoic acid (22:6 ( n−3)) were significantly higher when formula containing 4% rather than 1% 18:3 ( n−3) was fed, suggesting that 1% 18:3 ( n−3) may limit tissue ( n−3) fatty acid accretion. These results suggest that future studies of essential fatty acid requirements. specifically 18:3 ( n−3), should consider possible influences on the saturated fatty acids which also play a functional role in tissue structural lipids.