A study to investigate the effect of taking CoenzymeQ10 supplements on abnormal artery blood vessel function in people with Type 2 diabetes who are on best-dose treatment with statin medication.

INTERVENTION: 12 week crossover study of Coenzyme Q10 in subjects with Type 2 diabetes who are receiving optimal dose statin therapy. CONDITION: Endothelial dysfunction in Type 2 Diabetes PRIMARY OUTCOME: Brachial artery ultrasound: change in %FMD (flow‐mediated dilatation, endothelium‐mediated). SECONDARY OUTCOME: 1.Forearm plethysmography: changes in forearm blood flow 2.Non‐invasive measures of arterial stiffness (applanation tonometry and arterial pulse wave analysis): Small and large artery compliance, Augmentation index, and Pulse wave velocity. 3. Biological Markers. INCLUSION CRITERIA: Subjects with type 2 diabetes; treatment with HMG‐CoA reductase inhibitor (statin) at a stable dose for 6 weeks; fasting LDL‐cholesterol<2.5mmol/L; brachial artery FMD 5.50% on screening ultrasound.