Excessive dietary linoleic acid induces proinflammatory markers in rats.
Following the historical dietary recommendations, the substitution of polyunsaturated fatty acids (PUFAs) for saturated fatty acids (SFAs) resulted in a dramatic increase of linoleic acid (LA) in the Western diet. While proatherogenic properties of SFAs have been described, the involvement of LA on the inflammatory process remains controversial. Herein, we evaluated the effects of an excessive LA intake on the cytokine-induced expression of endothelial adhesion molecules vascular cell adhesion molecule-1 (VCAM-1) and intercellular cell adhesion molecule-1 (ICAM-1), through the nuclear factor (NF)-κB pathway, in comparison with a control diet and regarding a "positive" SFA diet. Wistar rats were fed experimental diets - a control diet or diets enriched with LA or SFA - for 11 weeks. Plasma lipid parameters and proinflammatory cytokine production such as interleukin-1β and tumor necrosis factor (TNF)-α were analyzed. Expression of endothelial adhesion molecules and NF-κB was determined by immunohistochemical analysis. No difference was observed in body weight. The enriched diets did not affect triglyceride and total cholesterol levels in plasma. Our results demonstrated that excessive dietary LA intake increased TNF-α levels (P<.05) in plasma. Rats fed the LA-enriched diet showed a significantly higher expression of VCAM-1, ICAM-1 and NF-κB in aortas. In addition, our results demonstrated that an excess of LA is more efficient to activate endothelial molecular process than an excess of SFA. The present study provides further support for the proinflammatory properties of LA and suggests an LA-derivatives pathway involved in the inflammatory process.
Laboratoire de Biochimie et Nutrition Humaine, INRA USC 2012, Agrocampus Ouest, Rennes, France.
Justine
J
Marchix
Laboratoire de Biochimie et Nutrition Humaine, INRA USC 2012, Agrocampus Ouest, Rennes, France.
Benjamin
B
Choque
Laboratoire de Biochimie et Nutrition Humaine, INRA USC 2012, Agrocampus Ouest, Rennes, France.
Maryline
M
Kouba
INSERM U620, IFR 120 Core histopathology platform, University of Rennes 1, Rennes, France.
Alain
A
Fautrel
Laboratoire de Biochimie et Nutrition Humaine, INRA USC 2012, Agrocampus Ouest, Rennes, France.
Daniel
D
Catheline
Laboratoire de Biochimie et Nutrition Humaine, INRA USC 2012, Agrocampus Ouest, Rennes, France. Electronic address: philippe.legrand@agrocampus-ouest.fr.
Philippe
P
Legrand
D000818:Animals; D001011:Aorta / Q000378:metabolism; D001835:Body Weight; D051546:Cyclooxygenase 2 / Q000378:metabolism; D004032:Diet; D042783:Endothelial Cells / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D007150:Immunohistochemistry; D007249:Inflammation / Q000378:metabolism*; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D019787:Linoleic Acid / Q000008:administration & dosage*; D008055:Lipids / Q000737:chemistry; D016328:NF-kappa B / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
D005227:Fatty Acids; D053583:Interleukin-1beta; D008055:Lipids; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D019787:Linoleic Acid; D051546:Cyclooxygenase 2
Adhesion molecules; Diet; Endothelial activation; Linoleic acid; Saturated fatty acids; Tumor necrosis factor-α