Influence of coenzyme Q10 and cerivastatin on the flow-mediated vasodilation of the brachial artery: results of the ENDOTACT study

Aim: Endothelial dysfunction (ED) is the functional prestep in atherosclerosis. Aim of the present study was to evaluate the effects of a potent antioxidant (coenzyme Q10, CoQ10) and of cerivastatin on ED of the brachial artery. Methods and Results: Twenty-five male patients with manifest ED (flow-mediated vasodilation [FMD%]<4.5%) were included in this prospective, randomized, cross-over study. ED of the brachial artery was assessed by the use of high-resolution ultrasound. Each patient had to pass through three treatment phases ((1) single therapy with cerivastatin (C), (2) single therapy with CoQ10, (3) combination therapy). FMD% significantly improved throughout all treatment phases ((1) 3.50±4.05% vs. 8.80±6.39%, p=0.009; (2) −0.25±4.0% vs. 7.06%±4.39%, p=0.004; (3) 3.14±3.54% vs. 8.82±5.78%, p=0.011). C led to a significant decrease of CoQ10 plasma levels (1.23±0.34 vs. 0.87±0.39 μg/ml, p=0.004). Conclusion: Our results indicate a positive influence of CoQ10 supplementation on human ED, which appears to be independent of lipid lowering. Although large-scale studies evaluating other antioxidants failed to demonstrate a positive prognostic effect, Q10 has never been evaluated in larger trials. Experimental as well as clinical results indicate that CoQ10 warrants further attention in atherosclerosis research.