title: Inverse modifications of heart and liver alpha-tocopherol status by various dietary n-6/n-3 polyunsaturated fatty acid ratios.
abstract: The effect of dietary n-6/n-3 fatty acid ratio on alpha-tocopherol homeostasis was investigated in rats. Animals were fed diets containing fat (17% w/w) in which the n-6/n-3 ratio varied from 50 to 0.8. This was achieved by combining corn oil, fish oil, and lard. The polyunsaturated to saturated ratio and total alpha-tocopherol remained constant in all diets. Results showed that enrichment of n-3 polyunsaturated fatty acids in the diet, even at a low amount (3.9% w/w), resulted in a dramatic reduction of blood alpha-tocopherol concentration, which, in fact, is the result of a decrease in plasma lipids, since the alpha-tocopherol to total lipids ratio was not significantly altered. The most striking effect observed was a considerable alpha-tocopherol enrichment (x 4) of the heart as its membranes became enriched with n-3 polyunsaturated fatty acids. This process appeared even with a low amount of fish oil (3.9% w/w) added to the diet. Accordingly, a strong positive correlation was found between heart alpha-tocopherol and docosahexaenoic acid (r = 0.86) or docosahexaenoic acid plus eicosapentaenoic acid levels (r = 0.84). Conversely, the liver alpha-tocopherol level dropped dramatically when n-3 polyunsaturated fatty acids were gradually added to the diet. It is concluded that fish oil intake dramatically alters the alpha-tocopherol homeostasis in rats.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, U130, Marseille, France.
authors.forename: M
authors.initials: M
authors.lastname: Chautan
authors.forename: R
authors.initials: R
authors.lastname: Calaf
authors.forename: J
authors.initials: J
authors.lastname: Léonardi
authors.forename: M
authors.initials: M
authors.lastname: Charbonnier
authors.forename: M
authors.initials: M
authors.lastname: Andre
authors.forename: H
authors.initials: H
authors.lastname: Portugal
authors.forename: A M
authors.initials: AM
authors.lastname: Pauli
authors.forename: H
authors.initials: H
authors.lastname: Lafont
authors.forename: G
authors.initials: G
authors.lastname: Nalbone
mesh_terms: D000818:Animals; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage*; D006706:Homeostasis; D008055:Lipids / Q000097:blood; D008099:Liver / Q000378:metabolism*; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D014810:Vitamin E / Q000097:blood / Q000378:metabolism*
chemical_list: D004042:Dietary Fats, Unsaturated; D008055:Lipids; D014810:Vitamin E