Recently, it has been reported that dietary supplementation with grape seed extract (GSE) ameliorates endothelial function and increase nitric oxide (NO) bioavailability. Thus, we investigated if elevated blood pressure and aortic stiffness (AoS) characterized in obese individuals are attenuated following acute GSE supplementation. Twenty men (obese=10; normal body weight (NBW)=10) participated in this study. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR), and AoS were compared 2 h after ingestion of GSE or placebo (PL) on different days, 1 wk apart. Compared with the PL, GSE supplementation significantly decreased SBP (NBW: 103±4 vs. 99±3 mmHg; obese: 118±3 vs. 112±5 mmHg) and MAP (NBW: 75±2 vs. 72±2 mmHg; obese: 86±3 vs. 84±3 mmHg) in both groups, while there were no differences in HR, SV, DBP, TPR, and AoS. GSE supplementation significantly decreased CO in only obese group. In NBW group, TPR tended to be decreased, but there was no significant difference. Our study suggests that acute supplementation with GSE reduced both SBP and MAP via a reduction in CO in obese individuals and decreased peripheral vasoconstriction in NBW group.
Keywords: blood pressure; endothelial function; grape seed extract; nitric oxide; vasoconstriction.