Dietary type and amount of fat modulate lipid metabolism gene expression in liver and in adipose tissue in high-fat diet-fed rats.
OBJECTIVE
Dietary fat plays a central role in the development of obesity. However, the metabolic consequences of dietary fat can vary depending on their fatty acid composition. Therefore, the aim of the present work was to study the effect of the type and amount of dietary fat on the expression of genes controlling lipogenesis and fatty acid oxidation in the liver or adipose tissue of rats.


METHODS
The expression of hepatic or adipose tissue lipid metabolic genes from Sprague Dawley or Zucker(fa/fa) rats, respectively, was measured after chronic consumption of diets containing different types/amounts of dietary fats or after rats were adapted for 2 months to a high-fat Western diet and then fed different types and amounts of fats.


RESULTS
Each fat or oil in the diet regulated differentially the expression of transcription factors involved in lipogenesis and fatty acid oxidation as well as some of its target genes in liver. The expression of these genes after a chronic consumption of a high-fat Western diet was reestablished in the presence of less dietary fat and was dependent on the type of fat. In obese Zucker(fa/fa) rats, consumption of a high-fat diet repressed the expression of lipogenic, fatty acid oxidation and thermogenic genes in adipose tissue.


CONCLUSIONS
Type of fat influences the expression of genes that are involved in lipid metabolism in liver and adipose tissue, but this response is repressed when the amount of dietary fat is excessive, diminishing the differences between each type of fat.
Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México, D.F., Mexico.
Armando R
AR
Tovar
Andrea
A
Díaz-Villaseñor
Natally
N
Cruz-Salazar
Guillermo
G
Ordáz
Omar
O
Granados
Berenice
B
Palacios-González
Claudia
C
Tovar-Palacio
Patricia
P
López
Nimbe
N
Torres
D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D004041:Dietary Fats / Q000008:administration & dosage* / Q000378:metabolism; D015870:Gene Expression; D050356:Lipid Metabolism / Q000235:genetics*; D008099:Liver / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011924:Rats, Zucker; D060888:Real-Time Polymerase Chain Reaction
D004041:Dietary Fats