Dietary lipids regulate beta-oxidation enzyme gene expression in the developing rat kidney.
This study examines the ability of dietary lipids to regulate gene expression of mitochondrial and peroxisomal fatty acid beta-oxidation enzymes in the kidney cortex and medulla of 3-wk-old rats and evaluates the role of glucagon or of the alpha-isoform of peroxisome proliferator-activated receptor (PPARalpha) in mediating beta-oxidation enzyme gene regulation in the immature kidney. The long-chain (LCAD) and medium-chain acyl-CoA dehydrogenases (MCAD) and acyl-CoA oxidase (ACO) mRNA levels were found coordinately upregulated in renal cortex, but not in medulla, of pups weaned on a high-fat diet from day 16 to 21. Further results establish that switching pups from a low- to a high-fat diet for only 1 day was sufficient to induce large increases in cortical LCAD, MCAD, and ACO mRNA levels, and gavage experiments show that this upregulation of beta-oxidation gene expression is initiated within 6 h following lipid ingestion. Treatment of pups with clofibrate, a PPARalpha agonist, demonstrated that PPARalpha can mediate regulation of cortical beta-oxidation enzyme gene expression, whereas glucagon was found ineffective. Thus dietary lipids physiologically regulate gene expression of mitochondrial and peroxisomal beta-oxidation enzymes in the renal cortex of suckling pups, and this might involve PPARalpha-mediated mechanisms.
Ouali
F
F
Institut National de la Santé et de la Recherche Médicale Unité 319, Université Paris 7 Denis Diderot, 75251 Paris Cedex 05, France.
Djouadi
F
F
Merlet-Bénichou
C
C
Bastin
J
J
D042964:Acyl-CoA Dehydrogenase; D044942:Acyl-CoA Dehydrogenase, Long-Chain / Q000378:metabolism*; D042962:Acyl-CoA Oxidase; D000818:Animals; D004041:Dietary Fats / Q000008:administration & dosage*; D005227:Fatty Acids / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D007672:Kidney Cortex / Q000254:growth & development / Q000378:metabolism*; D007679:Kidney Medulla / Q000254:growth & development / Q000378:metabolism*; D010088:Oxidoreductases / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D004041:Dietary Fats; D005227:Fatty Acids; D010088:Oxidoreductases; D042962:Acyl-CoA Oxidase; D042964:Acyl-CoA Dehydrogenase; D044942:Acyl-CoA Dehydrogenase, Long-Chain