Sustained Benefits in Vascular Function Through Flavanol-Containing Cocoa in Medicated Diabetic Patients

Department for Cardiology, Pulmonology, and Vascular Medicine, University Hospital RWTH Aachen, Aachen, Germany.
Journal of the American College of Cardiology (Impact Factor: 15.34). 07/2008; 51(22):2141-9. DOI: 10.1016/j.jacc.2008.01.059
Source: PubMed

ABSTRACT Our goal was to test feasibility and efficacy of a dietary intervention based on daily intake of flavanol-containing cocoa for improving vascular function of medicated diabetic patients.
Even in fully medicated diabetic patients, overall prognosis is unfavorable due to deteriorated cardiovascular function. Based on epidemiological data, diets rich in flavanols are associated with a reduced cardiovascular risk.
In a feasibility study with 10 diabetic patients, we assessed vascular function as flow-mediated dilation (FMD) of the brachial artery, plasma levels of flavanol metabolites, and tolerability after an acute, single-dose ingestion of cocoa, containing increasing concentrations of flavanols (75, 371, and 963 mg). In a subsequent efficacy study, changes in vascular function in 41 medicated diabetic patients were assessed after a 30-day, thrice-daily dietary intervention with either flavanol-rich cocoa (321 mg flavanols per dose) or a nutrient-matched control (25 mg flavanols per dose). Both studies were undertaken in a randomized, double-masked fashion. Primary and secondary outcome measures included changes in FMD and plasma flavanol metabolites, respectively.
A single ingestion of flavanol-containing cocoa was dose-dependently associated with significant acute increases in circulating flavanols and FMD (at 2 h: from 3.7 +/- 0.2% to 5.5 +/- 0.4%, p < 0.001). A 30-day, thrice-daily consumption of flavanol-containing cocoa increased baseline FMD by 30% (p < 0.0001), while acute increases of FMD upon ingestion of flavanol-containing cocoa continued to be manifest throughout the study. Treatment was well tolerated without evidence of tachyphylaxia. Endothelium-independent responses, blood pressure, heart rate, and glycemic control were unaffected.
Diets rich in flavanols reverse vascular dysfunction in diabetes, highlighting therapeutic potentials in cardiovascular disease.


Available from: Carl L Keen, May 30, 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: Polyphenols and other compounds found in cocoa and chocolate have therapeutic potential in the management of diabetes in humans. Polyphenols benefits have been proposed supported by in vitro studies, animal work and clinical trials, which have been conducted mostly in healthy volunteers. The energy dense formulations of many cocoa and chocolate products which can be up to 50% sugar by weight have given the perception that chocolate may be harmful through its contribution to obesity. A review of both clinical trial databases and published literature yielded 15 registered trials and seven published studies. The published data interventions reported are diverse vary widely in quality, including poor selection of control products or inadequate blinding procedures. There are also inconsistencies in reporting of data with limited information on the effect of cocoa and chocolate supplementation on weight and glycemic control despite the potential benefits reported with respect to the cardiovascular risk factors of endothelial function and lipids. More studies are required powered for primary clinical outcomes together with the development of standardized product formulations that optimize the dose of polyphenols within a palatable and energy restricted product.
    Journal of Agricultural and Food Chemistry 03/2015; DOI:10.1021/acs.jafc.5b00776 · 3.11 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Significance: Disruption of endothelial function is considered as a key event in the development and progression of atherosclerosis. Endothelial nitric oxide synthase is a central regulator of cellular function important to maintain endothelial homeostasis. Recent Advances: Endothelial homeostasis encompasses acute responses such as adaption of flow to tissue´s demand and more sustained responses to injury such as re-endothelialization and sprouting of endothelial cells and attraction of circulating angiogenic cells (CAC) both supporting repair of damaged endothelium. The balance and the intensity of endothelial damage and repair might be reflected by changes in circulating endothelial microparticles (EMP) and CAC. Whereas flow-mediated vasodilation (FMD) is a generally accepted clinical read-out of nitric oxide dependent vasodilation, EMP are up-coming prognostically validated markers of endothelial injury and CAC are reflective of the regenerative capacity with both expressing a functional eNOS. These markers can be integrated in a clinical endothelial phenotype, reflecting the net result between damage from risk factors and endogenous repair capacity with nitric oxide representing a central signaling molecule. Critical Issues: Improvements of reproducibility and observer-independence of FMD measurements and definitions of relevant EMP and CAC subpopulations warrant further research. Future Directions: Endothelial homeostasis may be a clinical therapeutic target for cardiovascular health maintenance.
    Antioxidants and Redox Signaling 10/2014; DOI:10.1089/ars.2014.6158 · 7.67 Impact Factor
  • Free Radical Biology and Medicine 11/2012; 53:S87. DOI:10.1016/j.freeradbiomed.2012.10.347 · 5.71 Impact Factor