title: Nutritional regulation of apolipoprotein genes: effect of dietary carbohydrates and fatty acids.
abstract: The effect of nutritional factors on apolipoprotein gene expression by rat liver were studied. Dietary carbohydrates or fatty acids regulate the expression of apo E gene, by altering either gene transcription or mRNA stability. Conversely, apo AI regulation occurs at a post transcriptional level. In vivo and in vitro experiments gave contradictory results concerning apo B gene expression. The more dramatic changes in plasma lipids and apolipoproteins are obtained under dietary fish oil. Hepatocytes from fish oil-fed rats retain for several days modification in fatty acid metabolism, i.e. a shift in oleic acid channeling towards oxidation at the expense of esterification and a reduced ability to synthesize and secrete triacylglycerol. These modifications are paralleled with a decrease in the synthesis and in the secretion of apo Bs. Hepatocytes from fish oil fed rats secrete degradative forms of apo B which might result from either a sluggish VLDL synthesis and secretion or a more specific effect of n-3 long chain polyunsaturated fatty acid peroxidative products. Hepatocytes from fish oil fed rats exhibit a reduced ability to synthesize cholesterol, associated with a decrease in apo AI synthesis and secretion without any modification in apo AI mRNA. In contrast, the hepatocytes exhibit a concomitent decrease in apo E synthesis and secretion and in cellular apo E mRNA levels.
authors.affiliation: Laboratoire de biochimie (CNRS URA 1283) CHU Saint-Antoine, Université Pierre et Marie Curie, Paris, France.
authors.forename: A
authors.initials: A
authors.lastname: Ribeiro
authors.forename: M
authors.initials: M
authors.lastname: Mangeney
authors.forename: P
authors.initials: P
authors.lastname: Cardot
authors.forename: C
authors.initials: C
authors.lastname: Loriette
authors.forename: J
authors.initials: J
authors.lastname: Chambaz
authors.forename: Y
authors.initials: Y
authors.lastname: Rayssiguier
authors.forename: G
authors.initials: G
authors.lastname: Béréziat
mesh_terms: D000818:Animals; D001053:Apolipoproteins / Q000235:genetics*; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D004041:Dietary Fats / Q000494:pharmacology*; D005227:Fatty Acids / Q000494:pharmacology*; D005786:Gene Expression Regulation; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D001053:Apolipoproteins; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D005227:Fatty Acids