Insulin Regulation of Lipolysis and Lipolysis Proteins

Insulin Regulation of Lipolysis and Lipolysis Proteins

These studies will define the abnormalities in the adipocyte proteins that are involved in the failure of insulin to suppress lipolysis normally in humans with upper body obesity and will help discover the mechanism by which pioglitazone, a medication used to treat type 2 diabetes and improve insulin resistance, improves insulin-regulation of adipocyte fatty acid metabolism.

1. The investigators will determine whether impaired insulin-induced suppression of lipolysis (as measured by IC50) is related to the above mentioned lipolysis proteins in groups of volunteers known to vary widely with regards to abdominal adipocyte size and regulation of adipose tissue lipolysis.
2. The investigators will determine whether the improved insulin regulation of lipolysis resulting from treatment with the PPARγ agonist pioglitazone, with or without weight loss, can be linked to specific changes in sets of PPARγ-responsive adipocyte lipolysis proteins in UBO adults.

Inclusion Criteria:

• Men and Women between the ages of 18 and 55.
• Women will be premenopausal
• Non obese adults BMI between 18-25
• Obese BMI 30-38

Exclusion Criteria, Pioglitazone package insert of contraindications for use:

• Initiation in patients with established New York Heart Associations (NYHA) class III or IV Heart failure.
• Use in patients with known hypersensitivity to pioglitazone or any other component of ACTOSE.