Dietary Triacylglycerols with Palmitic Acid (16:0) in the 2-Position Increase 16:0 in the 2-Position of Plasma and Chylomicron Triacylglycerols, but Reduce Phospholipid Arachidonic and Docosahexaenoic Acids, and Alter Cholesteryl Ester Metabolism in Formula-Fed Piglets ,

Abstract

Milk triacylglycerols have an unusual fatty acid distribution, with palmitic acid (16:0) esterified predominately at the center (sn-2) position. Other dietary triacylglycerols contain 16:0 predominantly at the sn-1,3 positions. This study was designed to evaluate the effect of formula triacylglycerol fatty acid distribution on the composition and distribution of plasma lipoprotein fatty acids in piglets fed formula containing synthesized triacylglycerols or palm olein oil with about 32 or 4.2% 16:0, respectively, in fatty acids at the sn-2 position, with comparison to piglets fed sow’s milk. Feeding formula with 16:0 at the triglyceride sn-2 position or sow’s milk resulted in higher chylomicron triacylglycerol sn-2 16:0 than when palm olein was fed. This suggests that dietary triacylglycerol sn-2 position fatty acids are conserved during digestion, absorption and reassembly to chylomicron triacylglycerols. The increased chylomicron triacylglycerol sn-2 position 16:0 in piglets fed synthesized triacylglycerols was accompanied by lower chylomicron triacylglycerol arachidonic and docosahexaenoic acid than in piglets fed formula with palm olein, suggesting an interaction between dietary triacylglycerol saturated fatty acid distribution and (n-6) and (n-3) fatty acid transport.