AGE-DEPENDENT INCREASE IN ENDOTHELIAL MICROPARTICLES IN HEALTHY SUBJECTS: IMPACT OF COCOA FLAVANOLS

Abstract

Background: Clinical studies show that cocoa flavanols (CF) can decrease vascular stiffness and blood pressure and improve endothelial function even in healthy elderly subjects. We investigated whether age-dependent changes in circulating endothelial microparticles (EMPs) exist, whether these correlate with age-dependent vascular changes, and whether a CF-intervention also affects EMPs. Methods: EMPs were determined in 52 healthy subjects (22-75years) by flow cytometry. Endothelial function (flow-mediated-vasodilation; FMD), blood pressure, and wall-shear-stress (WSS) were measured. Using pulse-wave-analysis, pulse wave velocity (PWV) and aortic augmentation index (AIX) were measured. 22 young (<35yrs) and 20 elderly (50-80yrs) non-smoking healthy male consumed either CF-containing-drink [450mg] or nutrient-matched, CF-free-control BID for 14 days. Measurements were taken after overnight fasting before and 1h after the first drink on day 1 and day 14. Results: With increasing age, CD62e+ but not CD31+/41- and CD144+-EMPs, increased. Significant correlations were found between age and systolic blood pressure (SBP) and AIX. In elderly subjects, we observed an increased BA diameter and hence reduced WSS and FMD. CD62e+ correlated with SBP and inversely with FMD. Following 2 weeks of daily CF intake, FMD and PWV improved in young and elderly individuals. CF decreased AIX and thus SBP in elderly. CD62e+ and CD31+/41--MPs but not CD144+ significantly decreased in both groups. The decrease in CD62e+ correlated with decreases in SBP, AIX, and inversely with FMD improvements. Conclusion: In healthy humans, cardiovascular aging is associated with EMPs indicative of endothelial injury and can be modulated by dietary CFs along with improvements in vascular function.