ubiquinone and 20-hydroxy-5-8-11-14-eicosatetraenoic-acid

The vascular benefits of statins might be attenuated by inhibition of coenzyme Q(10) (CoQ(10)) synthesis. We investigated whether oral CoQ(10) supplementation improves endothelial dysfunction in statin-treated type 2 diabetic patients.. In a double-blind crossover study, 23 statin-treated type 2 diabetic patients with LDL cholesterol <2.5 mmol/l and endothelial dysfunction (brachial artery flow-mediated dilatation [FMD] <5.5%) were randomized to oral CoQ(10) (200 mg/day) or placebo for 12 weeks. We measured brachial artery FMD and nitrate-mediated dilatation (NMD) by ultrasonography. Plasma F(2)-isoprostane and 24-h urinary 20-hydroxyeicosatetraenoic acid (HETE) levels were measured as systemic oxidative stress markers.. Compared with placebo, CoQ(10) supplementation increased brachial artery FMD by 1.0 +/- 0.5% (P = 0.04), but did not alter NMD (P = 0.66). CoQ(10) supplementation also did not alter plasma F(2)-isoprostane (P = 0.58) or urinary 20-HETE levels (P = 0.28).. CoQ(10) supplementation improved endothelial dysfunction in statin-treated type 2 diabetic patients, possibly by altering local vascular oxidative stress.

Topics: Adult; Aged; Blood Flow Velocity; Blood Pressure; Brachial Artery; Cholesterol, LDL; Cross-Over Studies; Diabetes Mellitus, Type 2; Double-Blind Method; Endothelium, Vascular; Humans; Hydroxyeicosatetraenoic Acids; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Middle Aged; Oxidative Stress; Placebos; Ubiquinone; Vasodilation