Cross-over Study on Effect of Lipid Lowering by Acipimox on Cardiac and Skeletal Muscle Mitochondrial Function

Inclusion Criteria: * Male or postmenopausal females * Age 40-70 years * Obese (BMI \> 30 kg/m2), non-insulin dependent type 2 diabetic patients and BMI matched control subjects without diabetes. * Generally healthy with specifically no known cardiovascular disease, dyslipidemia, or gastric ulcers (contra-ind. of Acipimox), which can affect the study parameters. * Must be on sulphonylurea(SU)- derivate or metformin therapy for at least six months with a constant dose for at least two months, or on dietary treatment for at least six months * Well-controlled diabetes: HbA1c\<8%. * Control subjects must have a plasma glucose lower than 6,1 mmol/L. * Stable dietary habits (no weight loss/gain \> 3 kg in the last 6 months) Exclusion Criteria: * Known cardiovascular disease, dyslipidemia, hepatic or renal failure and gastric ulcers. * Insulin dependent Diabetic patients. * Use of lipid lowering agents, except from Statins, as these do not affect triglycerides levels (with exception to Lipitor). * Use of Thiazolidines (glitazone/rosiglitazone/pioglitazone/troglitazone) * Use of anti-coagulants (not thrombocyte-aggregation inhibitors) * Aberrant ECG (with signs of ischemia or cardiac failure or arrythmia's) * Weight gain/loss \> 3 kg in the last 6 months. * Hb \< 7,3 in women, and \< 7,8 in men. * Contraindications for MRI scans: * Electronic implants such as pacemakers or neurostimulator * Iron-containing corpora aliena in eyes or brain * Some hearing aids and artificial (heart) valves which are contraindicated for MRS * Claustrophobia * Subjects, who do not want to be informed about unexpected medical findings, or do not wish that their physician is informed, cannot participate in the study.