Effects of Fenofibrate Therapy on Plasma Ubiquinol‐10 and Ubiquinone‐10 Levels in Japanese Patients with Hyperlipidemia and Type 2 Diabetes Mellitus

Study Objective. To assess the effects of fenofibrate therapy on concentrations of plasma ubiquinol-10 and ubiquinone-10—the reduced and oxidized forms, respectively, of coenzyme Q10. Design. Prospective, open-label, noncontrolled study. Setting. University clinic and laboratory. Patients. Eighteen patients with hyperlipidemia and type 2 diabetes mellitus. Intervention. Patients received fenofibrate 150 mg/day for 12 weeks. Measurements and Main Results. Metabolic parameters were assessed 4, 8, and 12 weeks after the start of fenofibrate treatment. Plasma ubiquinol-10 and ubiquinone-10 levels were measured by reverse-phase high-performance liquid chromatography. At 4, 8, and 12 weeks, significant reductions in fasting triglyceride levels and significant increases in high-density lipoprotein cholesterol levels were noted. Total cholesterol, low-density lipoprotein cholesterol, fasting plasma glucose, and adiponectin levels, however, did not change significantly. Plasma ubiquinol-10 concentrations significantly increased after 8 and 12 weeks (p<0.05 for both), whereas ubiquinone-10 concentrations tended to decease, especially at 12 weeks. Conclusion. Our findings suggest that fenofibrate may help produce energy or prevent oxidization by increasing plasma ubiquinol-10 concentration; this effect may protect against the development and progression of atherosclerosis. In addition, treatment with fenofibrate demonstrated a favorable effect on serum lipid parameters.