Abstract 14131: Dark Chocolate Enhances Artery Dilatation Via Nox2 Down-regulation in Patients With Peripheral Arterial Disease
BACKGROUND: Peripheral arterial disease (PAD) is a clinical setting characterized by an exceptionally high risk for cardiovascular events. Oxidative stress seems to play a role in impairing flow-mediated dilation (FMD) and contributing to atherosclerosis in patients with PAD. Cocoa seems to exert artery dilatation via oxidative stress inhibition.
OBJECTIVES: To investigate whether in PAD patients dark chocolate elicits artery dilatation via down-regulation of NOX2, the catalytic core of NADPH oxidase.
METHODS: Flow-mediated dilatation (FMD), oxidative stress (as assessed by urinary isoprostanes excretion), nitric oxide generation (as assessed by serum levels of nitrite/nitrate (NOx)), NOX2 activity (as assessed by blood levels of soluble NOX2 derived peptide (sNOX2-dp)) and serum epicatechin were studied in 18 PAD patients (9 males and 9 females, mean age 68±9 years) in a crossover, single-blind study. Patients were randomly allocated to 40 g dark chocolate (>85% cocoa) or 40 g of milk chocolate (≤35% cocoa). FMD, urinary isoprostanes, NOx and sNOX2-dp, platelet oxidative stress and NOX2 activation, were assessed at baseline and 2 h after chocolate ingestion.
RESULTS: After dark chocolate intake, urinary isoprostanes and sNOX2-dp significantly decreased and FMD and NOx significantly increased. No changes of the above variables were observed after milk chocolate intake. Serum epicatechin significantly increased only after dark chocolate ingestion. Ex-vivo study showed that after dark chocolate intake platelet 8-iso-PGF2α and NOX2 activation significantly decreased; no effect of milk chocolate was detected.
CONCLUSION: This study suggests that in PAD patients, cocoa enhances artery dilatation by lowering of NOX2 activation. These results could open new therapeutic strategies to counteract oxidative stress and atherosclerotic progression in PAD.
- © 2013 by American Heart Association, Inc.