Linoleate inhibits EPA incorporation from dietary fish-oil supplements in human subjects.
Thirty healthy male subjects were randomly allocated into one of two treatment groups: group H subjects were maintained on a high-linoleic acid (LA) diet with the saturated fatty acids kept low and those in group L were kept on a low-LA, low saturate diet. After a 3-wk run-in period, subjects consumed a fish-oil supplement containing 1.6 g eicosapentaenoic acid (EPA)/d and 0.32 g docosahexaenoic acid as triglycerides for a further 4 wk. The diets alone resulted in a significant change in neutrophil phospholipid LA (H = 12.7 +/- 2.9%, L = 9.0 +/- 0.9%; P less than 0.05). Dietary supplementation with fish oil resulted in a significant increase in EPA in neutrophil phospholipids that was greater in group L (mean 2.0 +/- 0.4%) than group H (mean 1.5 +/- 0.3%; P less than 0.005). Reductions in arachidonic acid concentrations in neutrophil membranes were not different, nor could differences in leukotriene B4 production be detected. Our study indicates that the ingestion of n-6 fatty acids within the diet is an important determinant of EPA incorporation into neutrophil membranes.
Cleland
L G
LG
Department of Paediatrics, Flinders Medical Centre, Bedford Park, Adelaide, Australia.
James
M J
MJ
Neumann
M A
MA
D'Angelo
M
M
Gibson
R A
RA
D004032:Diet; D004042:Dietary Fats, Unsaturated / Q000378:metabolism*; D015118:Eicosapentaenoic Acid / Q000493:pharmacokinetics*; D005227:Fatty Acids / Q000378:metabolism; D005395:Fish Oils / Q000493:pharmacokinetics*; D006801:Humans; D007975:Leukotriene B4 / Q000378:metabolism; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D009504:Neutrophils / Q000378:metabolism; D009994:Osmolar Concentration; D010743:Phospholipids / Q000378:metabolism
D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D005395:Fish Oils; D008041:Linoleic Acids; D010743:Phospholipids; D007975:Leukotriene B4; D019787:Linoleic Acid; D015118:Eicosapentaenoic Acid