Livingstone KM, Givens DI, Jackson KG, Lovegrove JA. - 45303 N - Atherosclerosis 2014 ; 234(1) : 65-72.
Objective : Dairy intake, despite its high saturated fatty acid (SFA) content, is associated with a lower risk of cardiovascular disease and diabetes. This in vitro study determined the effect of individual fatty acids (FA) found in dairy, and FA mixtures representative of a high SFA and a low SFA dairy lipid on markers of endothelial function in healthy and type II diabetic aortic endothelial cells.
Methods : Cells were incubated for 24 h with FA mixtures (400 µM) and individual FA: oleic acid (OA; 150 µM); palmitic acid (PA; 150 µM); stearic acid (SA: 40 µM); trans-palmitelaidic acid (trans-PA; 20 µM); trans-vaccenic acid (trans-VA; 20 µM); a-linolenic acid (ALA; 20 µM) and linoleic acid (LA; 20 µM). Cellular adhesion molecules (sICAM-1, sVCAM-1 and sE-selectin) and nitric oxide (NO) were measured using ELISA and a chemiluminescent-based assay, respectively. Relative gene expression of these markers, including the insulin receptor, was performed using real-time PCR as well as FA compositions of cell pellets by gas chromatography.
Results : FA mixtures affected sE-selectin concentrations (P = 0.008), with concentrations lower following the high SFA compared to the low SFA mixture (P = 0.004), while NO concentrations were higher in diabetic compared to healthy cells (P = 0.029). Individual FA affected NO (P = 0.007) and sE-selectin (P = 0.040) concentrations with an increase following PA incubation relative to all other FA treatments (P < 0.05). PA increased sE-selectin compared with other FA treatments (P < 0.05). sE-selectin concentrations were also higher in healthy compared to diabetic cells (P = 0.023). Expression of ICAM-1 and insulin receptor was up-regulated in healthy compared to diabetic cells (P = 0.014 and P = 0.006 respectively).
Conclusions : Healthy and type II diabetic cells respond differently to incubation with FA treatments. Overall, physiological concentrations of dairy FA, but not dairy FA mixtures, substantially affected markers of endothelial function.