title: Influence of habitual high dietary fat intake on endothelium-dependent vasodilation.
abstract: High-fat diets are associated with an increased risk of cardiovascular disease. A potential underlying mechanism for the increased cardiovascular risk is endothelial dysfunction. Nitric oxide (NO)-mediated endothelium-dependent vasodilation is critical in the regulation of vascular tone and overall vascular health. The aim of this study was to determine the influence of dietary fat intake on endothelium-dependent vasodilation. Forty-four middle-aged and older sedentary, healthy adults were studied: 24 consumed a lower fat diet (LFD; 29% ± 1% calories from fat) and 20 consumed a high-fat diet (HFD; 41% ± 1% calories from fat). Four-day diet records were used to assess fat intake, and classifications were based on American Heart Association guidelines (<35% of total calories from fat). Forearm blood flow (FBF) responses to acetylcholine, in the absence and presence of the endothelial NO synthase inhibitor N(G)-monomethyl-l-arginine (L-NMMA), as well as responses to sodium nitroprusside were determined by plethysmography. The FBF response to acetylcholine was lower (∼15%; P < 0.05) in the HFD group (4.5 ± 0.2 to 12.1 ± 0.8 mL/100 mL tissue/min) than in the LFD group (4.6 ± 0.2 to 14.4 ± 0.6 mL/100 mL tissue/min). L-NMMA significantly reduced the FBF response to acetylcholine in the LFD group (∼25%) but not in the HFD group. There were no differences between groups in the vasodilator response to sodium nitroprusside. These data indicate that a high-fat diet is associated with endothelium-dependent vasodilator dysfunction due, in part, to diminished NO bioavailability. Impaired NO-mediated endothelium-dependent vasodilation may contribute to the increased cardiovascular risk with high dietary fat intake.
authors.affiliation: a Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309, USA.
authors.forename: Caitlin A
authors.initials: CA
authors.lastname: Dow
authors.affiliation: a Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309, USA.|b Department of Medicine, University of Colorado Denver and the Health Sciences Center, Aurora, CO 80045, USA.|c Denver Health Medical Center, Denver, CO 80204, USA.
authors.forename: Brian L
authors.initials: BL
authors.lastname: Stauffer
authors.affiliation: a Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309, USA.
authors.forename: Jared J
authors.initials: JJ
authors.lastname: Greiner
authors.affiliation: a Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309, USA.|b Department of Medicine, University of Colorado Denver and the Health Sciences Center, Aurora, CO 80045, USA.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: DeSouza
mesh_terms: D000109:Acetylcholine / Q000097:blood; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D059305:Diet, High-Fat / Q000009:adverse effects*; D004041:Dietary Fats / Q000009:adverse effects* / Q000097:blood; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D052250:Nitric Oxide Synthase Type III / Q000097:blood; D009599:Nitroprusside; D010991:Plethysmography; D012307:Risk Factors; D014664:Vasodilation / Q000502:physiology*; D019323:omega-N-Methylarginine / Q000097:blood
chemical_list: D004041:Dietary Fats; D009599:Nitroprusside; D019323:omega-N-Methylarginine; D052250:Nitric Oxide Synthase Type III; D000109:Acetylcholine
keywords: cardiovascular disease; débit sanguin dans l’avant-bras; endothelium; endothélium; forearm blood flow; high-fat diet; maladie cardiovasculaire; nitric oxide; oxyde nitrique; régime riche en gras; vasodilatation; vasodilation