title: Increase of EPA-derived hydroxy, epoxy and dihydroxy fatty acid levels in human plasma after a single dose of long-chain omega-3 PUFA.
abstract: BACKGROUND
  Several supplementation studies with long-chain omega-3 polyunsaturated fatty acids (LC n-3 PUFA) describe an increase of EPA-derived hydroxy, epoxy and dihydroxy fatty acids in blood, while changes in levels of other LC n-3 and n-6 PUFA-derived oxylipins were minor. In order to investigate the kinetics of changes in oxylipin levels in response to LC n-3 PUFA ingestion, we conducted a single dose treatment study with healthy subjects.
  
  
  METHODS
  In the present kinetic study, we compared patterns of hydroxy, epoxy and dihydroxy fatty acids in plasma of 6 healthy men before and after 6, 8, 24, and 48h of fish oil (1008mg EPA and 672mg DHA) ingestion. Levels of EPA- as well as other LC PUFA-derived hydroxy, epoxy and dihydroxy fatty acids were analyzed in plasma by LC-MS. Additionally, levels of these oxylipins were compared with their parent PUFA levels in plasma phospholipids.
  
  
  RESULTS
  All EPA-derived oxylipin levels were significantly increased 6h after LC n-3 PUFA ingestion and gradually drop thereafter reaching the baseline levels about 48h after treatment. The relative increase in EPA plasma phospholipid levels highly correlated with the increase of plasma EPA-derived oxylipin levels at different time points. In contrast, plasma levels of arachidonic acid- and DHA-derived oxylipins as well as parent PUFA levels in plasma phospholipids were hardly changed.
  
  
  CONCLUSIONS
  Our findings demonstrate that a single dose of LC n-3 PUFAs can rapidly induce a shift in the EPA oxylipin profile of healthy subjects within a few hours. Taking the high biological activity of the EPA-derived epoxy fatty acids into account, even short-term treatment with LC n-3 PUFAs may cause systemic effects, which warrant further investigation.
authors.affiliation: Institute of Food Science and Human Nutrition, Leibniz University of Hannover, Germany. Electronic address: Schuchardt@nutrition.uni-hannover.de.
authors.forename: Jan Philipp
authors.initials: JP
authors.lastname: Schuchardt
authors.affiliation: Institute of Food Science and Human Nutrition, Leibniz University of Hannover, Germany.
authors.forename: Inga
authors.initials: I
authors.lastname: Schneider
authors.affiliation: Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover, Germany.
authors.forename: Ina
authors.initials: I
authors.lastname: Willenberg
authors.affiliation: Department of Entomology and Comprehensive Cancer Center, University of California, Davis, CA, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Entomology and Comprehensive Cancer Center, University of California, Davis, CA, USA.
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Hammock
authors.affiliation: Institute of Food Science and Human Nutrition, Leibniz University of Hannover, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hahn
authors.affiliation: Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover, Germany.
authors.forename: Nils Helge
authors.initials: NH
authors.lastname: Schebb
mesh_terms: D000328:Adult; D015118:Eicosapentaenoic Acid / Q000097:blood* / Q000737:chemistry*; D004951:Esterification; D015525:Fatty Acids, Omega-3 / Q000737:chemistry* / Q000494:pharmacology*; D064368:Healthy Volunteers; D006801:Humans; D007700:Kinetics; D008297:Male; D054883:Oxylipins / Q000097:blood; D010743:Phospholipids / Q000097:blood
chemical_list: D015525:Fatty Acids, Omega-3; D054883:Oxylipins; D010743:Phospholipids; D015118:Eicosapentaenoic Acid
keywords: Arachidonic acid; Eicosanoids; Eicosapentaenoic acid; Oxylipins