Coenzyme Q10 improves endothelial function

Left ventricular ischemic diastolic dysfunction is a cause of heart failure. Congestive heart failure occurs when the heart no longer pumps efficiently enough to provide the body with freshly-oxygenated blood. Endothelial dysfunction, described as a malfunction of the cells which line the blood vessels, plays a key role in the development of cardiovascular disease.

Researchers at the University of Hong Kong divided 56 men and women with left ventricular ischemic diastolic dysfunction into two groups, one receiving 300mg of coenzyme Q10 a day for eight weeks, and the other a placebo. Endothelial function was evaluated before and after the supplementation period and blood samples were taken to determine fasting blood glucose levels, mitochondrial function (measured by the plasma lactate/pyruvate ratio), markers of oxidative stress and other factors.

At the end of the study, CoQ10 levels had trebled in the supplemented group and were unchanged in the placebo group. Improvements in endothelial function linked to an increase in mitochondrial function were observed in the CoQ10-supplemented group. The benefits from CoQ10 appeared to be greater in those subjects with the most serious mitochondrial and endothelial dysfunction. No effect was seen on blood pressure, lipids, blood glucose, C-reactive protein or oxidative stress, suggesting that the benefits observed were due to the favourable effect of CoQ10 on mitochondrial function.

These results suggest that supplementing with CoQ10 reverses endothelial dysfunction in subjects at significant risk of cardiovascular disease, with no side-effects. (Atherosclerosis 2011 Feb. 17 [Epub ahead of print]