Effect of various n-3/n-6 fatty acid ratio contents of high fat diets on rat liver and heart peroxisomal and mitochondrial beta-oxidation.
The present work extends tissue investigations previously performed in rat gastric mucosa on lipid metabolism alterations caused by n-3 and n-6 fatty acid-enriched diets. Liver and heart tissues are here studied and demonstrated to undergo, upon exposure to high fat diets with various n-3/n-6 fatty acid ratio contents, biochemical and morphological changes which may be enumerated as follows: (1) Rat liver peroxisomal prostaglandin E2, fatty acid but not bile acid beta-oxidation rates are enhanced, especially upon the diet with the higher n-3/n-6 fatty acid ratio. Mitochondrial beta-oxidation rates are little or not affected by the high fat diets. (2) Rat liver carnitine acyltransferases are stimulated by the high fat diets, the more rich the n-3 fatty acid content, the more pronounced the stimulatory effect. (3) Rat heart peroxisomal and mitochondrial beta-oxidation rates were increased in animals receiving the n-3 fatty acid-enriched diet. At a low n-3/n-6 fatty acid ratio content of the diet, these oxidizing rate values were in control range. The carnitine acyltransferase activities were increased in rat heart to different extents, depending on the n-3/n-6 fatty acid ratio content of the diet. (4) Ultrastructural examination and morphometric determinations on hepatocytes from rats receiving the diets with the lowest and the highest n-3/n-6 fatty acid ratio contents disclose that in the latter case the numbers and fractional volumes of peroxisomes and mitochondria are significantly higher than in the former case.
North France Center for the Study of Childhood Epilepsy, Department of Paediatric Neurology, Hôpital B, Centre Hospitalier Universitaire de Lille.
J
J
Vamecq
L
L
Vallee
P L
PL
de la Porte
M
M
Fontaine
D
D
de Craemer
C
C
van den Branden
H
H
Lafont
R
R
Grataroli
G
G
Nalbone
D042962:Acyl-CoA Oxidase; D000818:Animals; D004041:Dietary Fats / Q000494:pharmacology*; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects*; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D008830:Microbodies / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D004041:Dietary Fats; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated; D010088:Oxidoreductases; D042962:Acyl-CoA Oxidase