A small clinical trial led by researchers at UC San Diego School of Medicine and VA San Diego Healthcare System (VASDHS) examined five profoundly ill patients with major damage to skeletal muscle mitochondria. Mitochondria are structures responsible for most of the energy produced in cells. These “fuel cells” are dysfunctional as a result of both type 2 diabetes and heart failure. Patients with heart failure and diabetes abnormalities in both the heart and skeletal muscle often complain of shortness of breath, lack of energy and have difficulty walking even short distances.
Doctors found that patients with advanced heart failure and type 2 diabetes showed improved mitochondrial structure after three months of treatment with epicatechin-enriched cocoa. Epicatechin is a flavonoid found in dark chocolate.
The trial participants consumed dark chocolate bars and a beverage with a total epicatechin content of approximately 100 mg per day for 3 months. Biopsies of skeletal muscle were conducted before and after treatment. After the 3-month treatment, the researchers looked at changes in mitochondria volume and the abundance of cristae, which are internal compartments of mitochondria that are necessary for efficient function of the mitochondria.
“The cristae had been severely damaged and decreased in quantity in these patients,” said one of the senior investigators, Francisco J. Villarreal, MD, PhD of UC San Diego’s Department of Medicine’s Division of Cardiology. “After 3 months, we saw recovery; cristae numbers back toward normal levels, and increases in several molecular indicators involved in new mitochondria production.”
The study was published by the journal Clinical and Translational Science.