Acute Antioxidant Consumption Improves Vascular Function in the Elderly

Abstract

Oxidative stress has been implicated in the age‐related decrement in vascular health, and may contribute to the reduced vasodilatory capacity in the elderly. To examine the impact of oxidative stress on age‐related vascular dysfunction, 27 young (26 ± 1 yrs) and 20 older (71 ± 2 yrs) healthy volunteers partook in a flow‐mediated vasodilation (FMD) protocol following consumption of either placebo or an antioxidant (AO) cocktail (Vitamin C, E, and Alphalipoic acid). Ultrasound Doppler was utilized to determine blood velocity and brachial artery diameter, and reactive hyperemia was quantified to normalize FMD for the shear stimulus. An age‐related decline in brachial artery vasodilation was observed (6.7 ± 0.7, young vs. 4.9 ± 0.3 %, older), but this age difference was no longer significant after FMD was normalized for shear rate (0.31 ± 0.03, young vs. 0.27 ± 0.03 %/s‐1•s). Following AO consumption, FMD improved in the elderly (4.9 ± 0.3 to 7.7 ± 0.7 %, placebo vs AO) but tended to decline in young (6.7 ± 0.7 to 5.7 ±0.7, placebo vs. AO), effects which remained after shear rate normalization. These data demonstrate that consumption of an AO cocktail at over‐the‐counter doses acutely improves endothelial function in the elderly, restoring brachial artery vasodilation to that of their younger, healthy counterparts. These findings thus support a possible role of AOs in the maintenance of vascular health in the elderly.