title: DHA-rich fish oil reverses the detrimental effects of saturated fatty acids on postprandial vascular reactivity.
abstract: BACKGROUND
  Experimental elevation of nonesterified fatty acids (NEFAs) impairs endothelial function, but the effect of NEFA composition is unknown.
  
  
  OBJECTIVE
  The objective was to test the effect of acute elevation of NEFAs enriched with either saturated fatty acids (SFAs) or SFAs with long-chain (LC) n-3 (omega-3) PUFAs on vascular function measured via flow-mediated dilatation (FMD), laser Doppler iontophoresis (LDI), and digital volume pulse (DVP).
  
  
  METHODS
  In 59 subjects (30 men and 29 women), repeated oral fat feeding of either palm stearin (SFA) or palm stearin with DHA-rich fish oil (SFA + LC n-3 PUFA) was performed on 2 separate occasions with continuous heparin infusion to elevate NEFAs for a duration of 60 to 240 min. Vascular function was measured at baseline and at the end of NEFA elevation; venous blood was collected for measurement of lipids and circulating markers of endothelial function.
  
  
  RESULTS
  NEFA elevation during consumption of the SFA-rich drinks was associated with a marked impairment of FMD, whereas consumption of SFAs + LC n-3 PUFAs improved FMD response, with a mean (±SEM) difference of 2.06 ± 0.29% (P < 0.001). Positive correlations were found with percentage weight of LC n-3 PUFAs in circulating NEFAs and change in FMD response [Spearman's rho (r(s)) = 0.460, P < 0.001]. LDI measures increased during both treatments (P ≤ 0.026), and there was no change in DVP indexes.
  
  
  CONCLUSIONS
  The composition of NEFAs can acutely affect FMD. The beneficial effect of LC n-3 PUFAs on postprandial vascular function warrants further investigation but may be mediated by nitric oxide-independent mechanisms. This trial is registered at clinicaltrials.gov as NCT01351324.
authors.affiliation: Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, University of Reading, United Kingdom. k.j.newens@reading.ac.uk
authors.forename: Katie J
authors.initials: KJ
authors.lastname: Newens
authors.forename: Abby K
authors.initials: AK
authors.lastname: Thompson
authors.forename: Kim G
authors.initials: KG
authors.lastname: Jackson
authors.forename: John
authors.initials: J
authors.lastname: Wright
authors.forename: Christine M
authors.initials: CM
authors.lastname: Williams
mesh_terms: D000328:Adult; D004041:Dietary Fats / Q000008:administration & dosage*; D004106:Dilatation; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000503:physiopathology; D005227:Fatty Acids / Q000009:adverse effects*; D005230:Fatty Acids, Nonesterified / Q000009:adverse effects* / Q000097:blood; D005260:Female; D005395:Fish Oils / Q000494:pharmacology*; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D007478:Iontophoresis; D008297:Male; D000073878:Palm Oil; D010938:Plant Oils / Q000008:administration & dosage; D019518:Postprandial Period; D018709:Statistics, Nonparametric; D014652:Vascular Diseases / Q000503:physiopathology / Q000517:prevention & control*
chemical_list: D004041:Dietary Fats; D005227:Fatty Acids; D005230:Fatty Acids, Nonesterified; D005395:Fish Oils; D010938:Plant Oils; D004281:Docosahexaenoic Acids; D000073878:Palm Oil; D006493:Heparin