title: Impaired postprandial endothelial function depends on the type of fat consumed by healthy men.
abstract: Postprandial lipemia impairs endothelial function possibly via an oxidative stress mechanism. A stearic acid-rich triacylglycerol (TAG) (shea butter) results in a blunted postprandial increase in plasma TAG compared with an oleic acid-rich TAG; however, its acute effects on endothelial function and oxidative stress are unknown. A randomized crossover trial (n = 17 men) compared the effects of 50 g fat, rich in stearic acid [shea butter blend (SA)] or oleic acid [high oleic sunflower oil (HO)], on changes in endothelial function [brachial artery flow-mediated dilatation (FMD)], arterial tone [pulse wave analysis (PWA), and carotid-femoral pulse wave velocity (PWV(c-f))], and oxidative stress (plasma 8-isoprostane F2alpha) at fasting and 3 h following the test meals. The postprandial increase in plasma TAG was lower (66% lower incremental area under curve) following the SA meal [28.3 (9.7, 46.9)] than after the HO meal [83.4 (57.0, 109.8); P < 0.001] (geometric means with 95% CI, arbitary units). Following the HO meal, there was a decrease in FMD [-3.0% (-4.4, -1.6); P < 0.001] and an increase in plasma 8-isoprostane F2alpha [10.4ng/L (3.8, 16.9); P = 0.005] compared with fasting values, but no changes followed the SA meal. The changes in 8-isoprostane F2alpha and FMD differed between meals and were 14.0 ng/L (6.4, 21.6; P = 0.001) and 1.75% (0.10, 3.39; P = 0.02), respectively. The reductions in PWA and PWV c-f did not differ between meals. This study demonstrates that a stearic acid-rich fat attenuates the postprandial impairment in endothelial function compared with an oleic acid-rich fat and supports the hypothesis that postprandial lipemia impairs endothelial function via an increase in oxidative stress.
authors.affiliation: Nutritional Sciences Division, King's College London, London SE1 9NH, United Kingdom. sarah.e.berry@kcl.ac.uk
authors.forename: Sarah E E
authors.initials: SE
authors.lastname: Berry
authors.forename: Sally
authors.initials: S
authors.lastname: Tucker
authors.forename: Radhika
authors.initials: R
authors.lastname: Banerji
authors.forename: Benyu
authors.initials: B
authors.lastname: Jiang
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Chowienczyk
authors.forename: Sonia M
authors.initials: SM
authors.lastname: Charles
authors.forename: Thomas A B
authors.initials: TA
authors.lastname: Sanders
mesh_terms: D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D001916:Brachial Artery / Q000502:physiology; D004041:Dietary Fats / Q000009:adverse effects / Q000145:classification; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology*; D005542:Forearm / Q000098:blood supply; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D018579:Patient Selection; D019518:Postprandial Period / Q000502:physiology*; D012016:Reference Values; D014664:Vasodilation
chemical_list: D004041:Dietary Fats; D008055:Lipids