Lipids

, Volume 39, Issue 6, pp 545–551

Incorporation of n−3 fatty acids into plasma and liver lipids of rats: Importance of background dietary fat

Articles

DOI: 10.1007/s11745-004-1261-z

Cite this article as:
MacDonald-Wicks, L.K. & Garg, M.L. Lipids (2004) 39: 545. doi:10.1007/s11745-004-1261-z

Abstract

The health benefits of long-chain n−3 PUFA (20∶5n−3 and 22∶6n−3) depend on the extent of incorporation of these FA into plasma and tissue lipids. This study aimed to investigate the effect of the background dietary fat (saturated, monounsaturated, or n−6 polyunsaturated) on the quantitative incorporation of dietary 18∶3n−3 and its elongated and desaturated products into the plasma and the liver lipids of rats. Female weanling Wistar rats (n=54) were randomly assigned to six diet groups (n=9). The fat added to the semipurified diets was tallow (SFA), tallow plus linseed oil (SFA-LNA), sunola oil (MUFA), sunola oil plus linseed oil (MUFA-LNA), sunflower oil (PUFA), or sunflower oil plus linseed oil (PUFA-LNA). At the completion of the 4-wk feeding period, quantitative FA analysis of the liver and plasma was undertaken by GC. The inclusion of linseed oil in the rat diets increased the level of 18∶3n−3, 20∶5n−3, and, to a smaller degree, 22∶6n−3 in plasma and liver lipids regardless of the background dietary fat. The extent of incorporation of 18∶3n−3, 20∶5n−3, and 22∶5n−3 followed the order SFA-LNA>MUFA-LNA>PUFA-LNA. Levels of 22∶6n−3 were increased to a similar extent regardless of the type of major fat in the rat diets. This indicates that the background diet affects the incorporation in liver and plasma FA pools of the n−3 PUFA with the exception of 22∶6n−3 and therefore the background diet has the potential to influence the already established health benefits of long-chain n−3 fatty acids.

Abbreviations

AA

arachidonic acid

LA

linoleic acid

LNA

α-linolenic acid

MUFA

monounsaturated FA

SFA

saturated FA

Copyright information

© AOCS Press 2004

Authors and Affiliations

  1. 1.Nutrition and Dietetics, School of Health Science, Faculty of Health, Level 3CallaghanAustralia