Effects of Glucagon Like Peptide-1(GLP-1) and Liraglutide on Brain Satiety and Reward Circuits and Feeding Behavior in Diabetes

liraglutide will be started with a titration period of 2 weeks: week 1 0.6mg once daily, week 2 1.2mg once daily. If well tolerated, treatment will be continued for 10 more weeks in dosage of 1.8mg once daily

Insulin glargine treatment consist a treatment period of 12 weeks. Treatment will start with a dosage of 10 IU once daily. Patient will self-titrate the insulin glargine dosage based on self-monitored fasting blood glucose (FBG) concentrations for the previous 3 days using the following guideline: If FBG levels are above 5.6 mmol/L (100-153 mg/dL) on 3 consecutive mornings, the daily dose is to be increased by 2 IU/day. If hypoglycemia documented by glucose concentration \< 3.3 mmol/L (60 mg/dL) or requiring assistance occurs without an easily identifiable reason (skipped meal, excessive physical activity), the daily dose is to be downregulated, with -2 IU/day

Exendin 9-39 will be infused intravenously at doses of 600 pM/kg • min. This will only be during one of the visit for the healthy lean controls and the T2DM group, and during two visits in the group with obesity planned for gastric bypass surgery