Diabetes reversion is observed after bariatric surgeries even before significant weight loss could explain it, mainly in predominantly malabsorptive procedures, followed by those combining malabsorption and gastric restriction. Changes in the hormonal communication between the digestive system (incretins)and the pancreas would explain the antidiabetogenic role of the surgery, so this effect could be obtained in nonobese, diabetic individuals.~Based in a surgery technique studied in a non-obese diabetic mouse model by Rubino and Marescaux(2004), wich reversed diabetes in those animals, we have performed a previous study in human volunteers with type 2 diabetes and overweight (non-obese). The surgery is a duodenal exclusion: the stomach volume is kept intact, maintaining the caloric ingestion and the weight reduces less than 5%, without the potential nutritional deprivations commonly seen in the bariatric surgery. We observed improvement of glycemic control and hemoglobin A1c, allied to reduction of medicines: insulin was withdrawn or significantly lowered. An standardized mixed meal tolerance test showed favorable changes in the gastrointestinal hormones that stimulate insulin secretion (incretins): increase of GLP-1 and reduction of GIP.~Further improvement of diabetes could be achieved by intervention in insulin resistance, another factor of diabetes pathophysiology. As that factor is related to visceral fat, we hypothesize that surgical removal of the major omentum, a great component of central adiposity, could beneficial .~In fact, surgical removal of visceral fat in rodents improves insulin sensitivity. A pilot study in human, obese volunteers submitted to gastric adjustable band was promising int this aspect.~This study will evaluate the mechanisms of amelioration of type 2 diabetes mellitus after duodenal exclusion surgery plus total omentectomy , by the method of standardized meal stimulus and insulin tolerance test, in human non-obese, volunteers with diabetes type 2 and known insulin secretion capacity.~The previously studied volunteers submitted to duodenal exclusion without omentectomy will be the control group.
Based in a surgery technique studied in a non-obese diabetic mouse model by Rubino and Marescaux(2004), wich reversed diabetes in those animals, we have performed a previous study in human volunteers with type 2 diabetes and overweight (non-obese). The surgery is a duodenal exclusion in wich the stomach volume is kept intact. We observed improvement of glycemic control and hemoglobin A1c, allied to reduction of medicines: insulin was withdrawn or significantly lowered.~Further improvement of diabetes could be achieved by intervention in insulin resistance, another factor of diabetes pathophysiology. As that factor is related to visceral fat, we hypothesize that surgical removal of the major omentum, a great component of central adiposity, could beneficial .~This study will evaluate the mechanisms of amelioration of type 2 diabetes mellitus after duodenal exclusion surgery plus total omentectomy, by the method of standardized meal stimulus and insulin tolerance test, in human non-obese volunteers with diabetes type 2 and known insulin secretion capacity.~The previously studied volunteers submitted to duodenal exclusion without omentectomy will be the control group.