Cocoa consumption reduces NF-κB activation in peripheral blood mononuclear cells in humans

Background and aims: Epidemiological studies have demonstrated an association between high-polyphenol intake and reduced incidence of atherosclerosis. The healthy effects of cocoa-polyphenols may be due to their antioxidant and anti-inflammatory actions, although the exact mechanisms are unknown and depend on the matrix in which cocoa-polyphenols are delivered. Nuclear factor kappa B (NF-kappa B) is a key molecule in the pathophysiology of atherosclerosis involved in the regulation of adhesion molecules(AM) and cytokine expression and its activation is the first step in triggering the inflammatory process. The aim of this study was to evaluate the effect of acute cocoa consumption in different matrices related to the bioavailability of cocoa-polyphenols in NF-kappa B activation and the expression of AM. Methods and results: Eighteen healthy volunteers randomly received 3 interventions: 40g of cocoa powder with milk (CM), with water (CW), and only milk (M). NF-kappa B activation in leukocytes and AM (sICAM, sVCAM, E-selectin) were measured before and 6h after each intervention. Consumption of CW significantly decreased NF-kappa B activation compared to baseline and to CM (P < 0.05, both), did not change after CM intervention, and significantly increased after M intervention (P = 0.014). sICAM-1 concentrations significantly decreased after 6h of CW and CM interventions (P <= 0.026; both) and E-selectin only decreased after CW intervention (P = 0.028). No significant changes were observed in sVCAM-1 concentrations. Conclusions: The anti-inflammatory effect of cocoa intake may depend on the bioavailability of bioactive compounds and may be mediated at least in part by the modulation of NF-kappa B activation and downstream molecules reinforcing the link between cocoa intake and health. (C) 2011 Elsevier B. V. All rights reserved.