Effects of Antidiabetic Medications on the Postprandial State in Prediabetes

Inclusion Criteria: * Diagnosis of Prediabetes - defined as either impaired fasting glucose (fasting glucose of 100-125 mg/dL), impaired glucose tolerance (2-hour postprandial blood glucose of 140-199 mg/dL after 75 gram oral glucose challenge), and/or a hemoglobin A1C ranging from 5.7% to 6.4% * Subjects are allowed, but not required, to be on statins, ACE-inhibitors, beta-blockers, angiotensin-receptor blockers, thiazide diuretics, and/or loop diuretics at doses that have been stable for at least the last 3 months * BMI between 30-35 kg/m2 (±1 kg/m2) * Body weight has been stable (±4-5 pounds) over the prior three months. * Women of childbearing age must agree to use an acceptable method of pregnancy prevention (barrier methods, abstinence, or surgical sterilization) for the duration of the study * Patients must have the following laboratory values: Hematocrit ≥ 34 vol% S. creatinine \< 1.5 mg/dl in men and 1.4 mg/dl in women AST (SGOT) \< 2.5 times ULN, ALT (SGPT) \< 2.5 times ULN, alkaline phosphatase\< 2.5 times ULN Exclusion Criteria: * History of Type 1 or Type 2 diabetes mellitus * History of diabetic ketoacidosis or hyperosmolar nonketotic coma * Pregnant or breastfeeding women * Patients must not be receiving lipid-lowering medications other than statins within the last 3 months * Patient must not be receiving metformin, DPP-IV inhibitors, GLP-1 agonists, thiazolidinediones, insulin, sulfonylureas, acarbose, SGLT-2 inhibitors, corticosteroids, or immunosuppressive therapy within the last 3 months and cannot take them for the duration of the study. Patient must not be receiving NSAIDS or antioxidant vitamins within the last 1 week, and cannot take them for the duration of the study. * Patients must not be on hormone replacement therapy. * Patients with diabetic gastroparesis * Patients with current tobacco use * Patients with active malignancy * Patients with history of urinary bladder cancer * Patients with dietary restrictions precluding a high-fat meal * Patients with a history of clinically significant heart disease (NYHA III or IV; more than non- specific ST-T wave changes on the EKG), peripheral vascular disease (history of claudication), or pulmonary disease (dyspnea on exertion of one flight or less; abnormal breath sounds on auscultation) will not be studied * Subjects with a history of any serious hypersensitivity reaction to the study medications * Prisoners or subjects who are involuntarily incarcerated * Subjects who are compulsorily detained for treatment of either a psychiatric or physical (e.g., infectious disease) illness * Subjects with known allergic reactions to the study medications or test meal * Subjects unwilling or unable to provide informed consent * Subjects determined by the investigator(s) to not be appropriate candidates for the study