Influence of Dietary Fat Intake on Endothelial Progenitor Cell Function (LB678)

Abstract

High dietary fat intake has been linked to promoting cardiovascular disease and increasing the risk of heart attack. Bone‐marrow derived circulating endothelial progenitor cells (EPCs) play an important role in repairing and maintaining the health of the cardiovascular system. Circulating EPCs home to sites of vascular damage to initiate a repair response. Declines in circulating EPC function has been linked to greater risk of cardiovascular disease and vascular events. It is currently unknown whether habitual consumption of a diet high in fat is associated with impairments in EPC function. Cells with phenotypic EPC characteristics were isolated from peripheral blood samples collected from 26 middle‐aged and older adults: 13 who habitually consumed a diet high in fat (蠅35% of total calories); 13 who habitually consumed a diet lower in fat (<35% of total calories). All subjects were sedentary and free of cardiometabolic disease. Diet was assessed using 4‐day food records and analyzed using a nutritional software. EPC functional characteristics were assessed by the following: colony formation (in vitro colony forming assay); migration (modified Boyden chamber); release of angiogenic growth factors (ELISA); and apoptosis (active intracellular caspase‐3). There were no significant differences between the high and lower fat groups in EPC colony formation (11±3 vs 8±2) and migration (1297±114 vs 1035±124 RFUs). Basal and phytohemagglutinin (PHA; 10 µg/mL) stimulated release of vascular endothelial growth factor (21.5±2.1 to 84.1±14.3 vs 22.9±1.4 to 95.6±14.1 ng/mL) and granulocyte colony stimulating factor (34.0±6.3 to 1246.9±283.6 vs 38.0±6.6 to 873.7±143.1 ng/mL). Moreover, there was no difference in unstimulated (0.3±0.1 vs 0.3±0.1 ng/mL) and stimulated (2.6±0.3 and 2.5±0.3 ng/mL) active caspase‐3 concentrations between the high and lower fat groups. In conclusion, regular consumption of a diet high in fat (蠅35% of calories) does not appear to adversely influence circulating EPC function in middle‐aged and older adults. Impaired EPC function may not contribute to the increased cardiovascular risk associated with a high fat diet.