Elucidating the Mechanism of Remission of Type 2 Diabetes in Morbid Obese Patients After Bariatric Surgery-focused on Beta Cell Function and Insulin Sensitivity Changes

In this study four groups including: Group I - Morbid Obese Diabetics, Group II - Morbid Obese Non Diabetics, Group III - Lean Diabetics, and Group IV - Lean Non Diabetics will be studies. The bariatric surgical procedure should include Laparoscopic Sleeve Gastrectomy (LSG). All participants will be assessed by members of a multidisciplinary obesity team including a surgeon, endocrinologist, dietician, and nurse specialist who will usually have input into patient selection.

Briefly the study will be explained to the each participant, and after his/her agreement, the informed Consent Form will be deliver to him/her for completion and signature. Within a week before surgery each enrolled participant of group I and II will be subjected to a medical questionnaire and other routine laboratory analyses before surgery such as fasting glucose, liver, renal, lipid and coagulation profiles. At this time a Mixed Meal Tolerance Test (MMTT) will be performed and blood samples will be collected for further analysis as it is described in the protocol.

Participants in group I and II will be admitted at Dasman Diabetes Institute for post-surgery follow up, performing MMTT, and donating blood samples on days 07, 15, 30, 60, 90, 180, and 360 post-surgery. Adipose, muscle biopsies, and a sample from remnant surgical tissue from these participants will be harvested during of the LSG (days 0). Participants in group I will be asked to monitor their fasting blood glucose level everyday at early morning and the dose of anti-hyperglycemia medications will be adjusted by the recommendation provided by the physician member of team. This data will be recorded as their continuous blood glucose monitoring.

Group III and IV participants, as control groups with no surgical intervention, will be subjected to the medical questionnaire and other routine laboratory analyses and MMTT in just one visit.

All demographic and clinical information collected from the participants will be recorded in the information form identified by identification number (ID number). Only samples from the cases that do not have any post-surgery related complications or not have any emergency clinical condition will be used for genomics and proteomics analysis.