Date: October 9, 2013
Welcome to our latest edition of the NCAlert – an e-update series sponsored by the National Confectioners Association. Our goal is to provide timely research updates, thoughtful commentaries and useful educational resources on the role of candy in health and well-being. We’re honored to share this edition with Francisco Villarreal MD, PhD, Professor of Medicine at University of California San Diego School of Medicine. Dr. Villarreal and his research team have recently published a cutting edge new series of articles detailing novel effects of cocoa flavanols on skeletal muscle structure and function.
In good health,
|Laura Shumow M.H.S.
Director of Scientific and Regulatory Affairs
National Confectioners Association
Disclosure: The views and opinions expressed below do not necessarily reflect the position of NCA or its members. NCA did not endorse or fund this research.
I am excited to share some recent findings by my research team at the University of California, San Diego, on the effects of cocoa flavanols on skeletal muscle structure and function. This pilot study was conducted in patients diagnosed with both heart failure and type 2 diabetes – who are known to have compromised heart and skeletal muscle function. Over a three month period, the patients consumed a prescribed amount of cocoa in the form of dark chocolate and a cocoa beverage designed to provide ~100 mg of the flavanol (-)-epicatechin. This study is observational only and had no control group.
In the first report, we focused on specific changes that occurred in the mitochondria of skeletal muscle in the patients following cocoa consumption. Mitochondria are the organelles that generate most of the energy (i.e., ATP) for all cells. As such, these organelles are crucial in maintaining muscle function. Results confirmed (as per previous findings by others) that mitochondria found in the muscle of heart failure patients are largely broken, which may explain the marked loss of muscle function observed in these patients. However, after three months of cocoa consumption, mitochondrial structure was partially restored.
In the second report, using the same muscle samples from the patients described above, we expanded our focus to examine the impact of cocoa consumption on the structural indicators of overall muscle integrity and growth. Using biochemical and microscopy techniques, the research team observed that heart failure/type 2 diabetes patients had a marked loss of structural components (in particular, dystrophin) that prevent muscle fiber injury. In addition, the levels for multiple regulators of muscle growth were also severely disrupted. Interestingly, following the three month cocoa consumption, the levels of structural components and regulators of growth notably recovered hinting at improvements in muscle function.
In the most recent report, and using the same patient samples, we examined the effects of cocoa flavanols on various indicators of oxidative stress within skeletal muscles. As previously reported by others, multiple indicators of tissue oxidative stress are greatly increased with heart failure and diabetes accompanied by a depletion of tissue antioxidant buffers such as glutathione. The diseases are also known to distort the pathways that regulate these systems. The patients in our study showed a striking recovery of markers of tissue oxidative stress and their control systems as well as antioxidant buffers following cocoa consumption compared to baseline. In looking at these three reports, we believe that the naturally occurring compounds in cocoa called flavanols are the key regulators of the mitochondrial, muscle and antioxidative effects we observed. Our hypothesis is that cocoa, as a food naturally concentrated in flavanols may not only neutralize high oxidative stress condition, but also have specific and beneficial actions on important control system pathways in muscle tissue.
The articles that relate to these findings are:
1. Taub P, Ramirez-Sanchez I, Ciaraldi T, Perkins G, Murphy A, Naviaux R, Hogan M, Maisel A, Henry R, Ceballos G, Villarreal F: Alterations in skeletal muscle indicators of mitochondrial structure and biogenesis in patients with type 2 diabetes and heart failure: Effects of epicatechin rich cocoa: Clin Trans Sci, 5:43-47, 2012
2. Taub P, Ramirez-Sanchez I, Ciaraldi T, Gonzalez-Basurto S, Coral-Vazquez R, Perkins G, Hogan M, Maisel A, Henry R, Ceballos G, Villarreal, F: Severe perturbations in skeletal muscle sarcomere structure of heart failure and type 2 diabetes patients: Restorative effects of (-)-epicatechin-rich cocoa. Clin Sci, 125:383-389, 2013
3. Ramirez-Sanchez I, Taub P, Nogueira L, Ciaraldi T, Hogan M, Maisel A, Henry R, Ceballos G, Villarreal, F: Modulation of skeletal muscle oxidative stress regulatory systems by (-)-epicatechin in heart failure and type 2 diabetes. In Press, Int J Cardiol, 2013
Francisco Villarreal MD, PhD
Professor of Medicine
UCSD School of Medicine