Brown Fat Activity and Bariatric Surgery

The Role of Alternatively Activated Brown Fat in Bariatric Surgery-mediated Metabolic Improvements

The mechanisms of bariatric surgery-induced weight loss go beyond reductions in calorie intake and may involve several other pathways. Recently, brown adipose tissue (BAT) has been added as another potential player. Activation of BAT results in enhanced energy expenditure and promotes weight loss. Here, the investigators will study the effects of bariatric surgery on BAT function by PET/CT studies and molecular analyses of adipose biopsies. The investigators will explore different pathways that may affect BAT activation in this patient population.

Inclusion Criteria:

• Age 20 - 50 years
• Body mass index (BMI) 35 - 55kg/m2

Exclusion Criteria:

• Endocrine disease (except hyperlipidemia and substituted hypothyroidism or type 2 diabetes with fasting glucose concentrations <120mg/dl), kidney disease, inflammatory bowel disease, autoimmune or rheumatologic diseases that require immunosuppressive treatment, active oncologic disease, heart failure.
• Medication for any of the above mentioned conditions.
• Antibiotic treatment in the past three months
• Pregnancy