Activation of Brown Adipose Tissue Metabolism Using Mirabegron

Inclusion Criteria: * Healthy subjects with normal glucose tolerance determined according to an oral glucose tolerance test; * BMI ≤ 30 kg/m2. Exclusion Criteria: * Plasma triglycerides \> 5.0 mmol/L at fasting; * More than 2 alcohol consumption per day; * More than 1 cigarette per day; * History of total cholesterol level \> 7 mmol/L, of cardiovascular disease, hypertensive crisis; * Treatment with fibrates, thiazolidinedione, insulin,betablockers or other drugs with effects on insulin resistance or lipid metabolism (exception for antihypertensive drugs, statins or metformin); * Presence of a noncontrolled thyroid disease, renal or hepatic disease, history of pancreatitis, bleeding diatheses, cardiovascular disease or any other serious medical conditions; * History of serious gastrointestinal disorders (malabsorption, peptic ulcer, gastroesophageal reflux having required a surgery, etc.); reflux having required a surgery, etc.); * Presence of a pacemaker; * Have undergone of PET study or CT scan in the past year; * Chronic administration of any medication;