title: Metabolic fate (absorption, β-oxidation and deposition) of long-chain n-3 fatty acids is affected by sex and by the oil source (krill oil or fish oil) in the rat.
abstract: The effects of krill oil as an alternative source of n-3 long-chain PUFA have been investigated recently. There are conflicting results from the few available studies comparing fish oil and krill oil. The aim of this study was to compare the bioavailability and metabolic fate (absorption, β-oxidation and tissue deposition) of n-3 fatty acids originating from krill oil (phospholipid-rich) or fish oil (TAG-rich) in rats of both sexes using the whole-body fatty acid balance method. Sprague-Dawley rats (thirty-six male, thirty-six female) were randomly assigned to be fed either a krill oil diet (EPA+DHA+DPA=1·38 mg/g of diet) or a fish oil diet (EPA+DHA+DPA=1·61 mg/g of diet) to constant ration for 6 weeks. The faeces, whole body and individual tissues were analysed for fatty acid content. Absorption of fatty acids was significantly greater in female rats and was only minimally affected by the oil type. It was estimated that most of EPA (>90 %) and more than half of DHA (>60 %) were β-oxidised in both diet groups. Most of the DPA was β-oxidised (57 and 67 % for female and male rats, respectively) in the fish oil group; however, for the krill oil group, the majority of DPA was deposited (82-83 %). There was a significantly greater deposition of DPA and DHA in rats fed krill oil compared with those fed fish oil, not due to a difference in bioavailability (absorption) but rather due to a difference in metabolic fate (anabolism v. catabolism).
authors.affiliation: 1School of Medicine,Deakin University,Geelong,VIC 3216,Australia.
authors.forename: Samaneh
authors.initials: S
authors.lastname: Ghasemifard
authors.affiliation: 2School of Life and Environmental Sciences,Deakin University,Warrnambool,VIC 3280,Australia.
authors.forename: Karen
authors.initials: K
authors.lastname: Hermon
authors.affiliation: 2School of Life and Environmental Sciences,Deakin University,Warrnambool,VIC 3280,Australia.
authors.forename: Giovanni M
authors.initials: GM
authors.lastname: Turchini
authors.affiliation: 1School of Medicine,Deakin University,Geelong,VIC 3216,Australia.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Sinclair
mesh_terms: D000818:Animals; D001682:Biological Availability; D004032:Diet; D004041:Dietary Fats / Q000378:metabolism / Q000493:pharmacokinetics; D004281:Docosahexaenoic Acids / Q000378:metabolism* / Q000493:pharmacokinetics; D015118:Eicosapentaenoic Acid / Q000378:metabolism* / Q000493:pharmacokinetics; D033201:Euphausiacea; D005260:Female; D005395:Fish Oils / Q000378:metabolism* / Q000493:pharmacokinetics; D005399:Fishes; D007408:Intestinal Absorption; D008297:Male; D009821:Oils / Q000378:metabolism* / Q000493:pharmacokinetics; D010084:Oxidation-Reduction; D010743:Phospholipids / Q000378:metabolism; D011897:Random Allocation; D017207:Rats, Sprague-Dawley; D012737:Sex Factors; D014018:Tissue Distribution; D014280:Triglycerides / Q000378:metabolism
chemical_list: D004041:Dietary Fats; D005395:Fish Oils; D009821:Oils; D010743:Phospholipids; D014280:Triglycerides; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid
keywords: BW body weight; DHA; DPA; EPA; Krill oil; LC-PUFA long-chain PUFA; Metabolic fate; PL phospholipids; Sex; Tissue deposition