Brain docosahexaenoic acid accretion is greater when supplied as phosphatidylcholine than as triacylglycerol in piglets (821.11)

Abstract

Introduction. Docosahexaenoic acid (DHA) is the most abundant n‐3 PUFA in the brain. Preformed DHA is more efficacious for brain DHA accretion than precursors, but the relative efficacy of DHA bound to phospholipid (PC) and/or triacylglycerol (TAG) has not been measured yet. Our aim was to determine the relative efficacy of DHA when provided in formula to the growing piglet as a dose of 13C‐DHA bound to the sn‐2 positions of either PC or TAG.Methods. Piglets (n=8 per group) were assigned to two identical formula diets from day 3 of life and provided with a single oral dose of TAG‐13C‐DHA or PC‐13C‐DHA at 16 days of life. At day 23, selected piglet organs were analyzed for 13C‐DHA and other fatty acid metabolites.Results. The PC‐13C‐DHA was 1.9‐fold greater in brain gray matter than TAG‐13C‐DHA, and was similarly more efficacious in synaptosomes, retina, liver, and RBC. Liver labeling was by far the greatest implying initial processing in that organ followed by export to other organs, and in turn that transfer from gut to bloodstream to liver in part drove the relative efficacy for tissue accretion. Apparent retroconversion to 22:5n‐3 was more than 2‐fold greater for PC and was much more prominent in neural tissue than in liver or RBC.Conclusions. These data directly support greater efficacy for PC as a carrier for LCPUFA compared to TAG, consistent with previous studies of arachidonic acid and DHA measured in other species.Grant Funding Source: Supported by NIH R01 AT007003