Abegg K, Corteville C, Docherty NG, Boza C, Lutz TA, Muñoz R, le Roux CW. Effect of bariatric surgery combined with medical therapy versus intensive medical therapy or calorie restriction and weight loss on glycemic control in Zucker diabetic fatty rats. Am J Physiol Regul Integr Comp Physiol 308: R321-R329, 2015. First published December 24, 2014 doi:10.1152/ajpregu.00331.2014.-Bariatric surgery rapidly improves Type 2 diabetes mellitus (T2DM). Our objective was to profile and compare the extent and duration of improved glycemic control following Roux-en-Y gastric (RYGB) bypass surgery and vertical sleeve gastrectomy (SG) and compare against calorie restriction/weight loss and medical combination therapy-based approaches using the Zucker diabetic fatty rat (ZDF) rodent model of advanced T2DM. Male ZDF rats underwent RYGB (n ϭ 15) or SG surgery (n ϭ 10) at 18 wk of age and received postsurgical insulin treatment, as required to maintain mid-light-phase glycemia within a predefined range (10 -15 mmol/l). In parallel, other groups of animals underwent sham surgery with ad libitum feeding (n ϭ 6), with body weight (n ϭ 8), or glycemic matching (n ϭ 8) to the RYGB group, using food restriction or a combination of insulin, metformin, and liraglutide, respectively. Both bariatric procedures decreased the daily insulin dose required to maintain mid-light-phase blood glucose levels below 15 mmol/l, compared with those required by body weight or glycemia-matched rats (P Ͻ 0.001). No difference was noted between RYGB and SG with regard to initial efficacy. SG was, however, associated with higher food intake, weight regain, and higher insulin requirements vs. RYGB at study end (P Ͻ 0.05). Severe hypoglycemia occurred in several rats after RYGB. RYGB and SG significantly improved glycemic control in a rodent model of advanced T2DM. While short-term outcomes are similar, long-term efficacy appears marginally better after RYGB, although this is tempered by the increased risk of hypoglycemia. bariatric surgery; Roux-en-Y gastric bypass; sleeve gastrectomy; glycemic control; medical therapy; caloric restriction; Zucker diabetic fatty rat ROUX-EN-Y GASTRIC BYPASS (RYGB) and vertical sleeve gastrectomy (SG) surgery can be used as a treatment alternative to intensive management in obese patients (body mass index Ͼ30 kg/m 2 ) with Type 2 diabetes mellitus (T2DM) (5, 29, 39).After these operations, most patients have improved glycemic control, and ϳ40% of patients achieve a HbA1c Ͻ42 mmol/ mol (6%) after one year. It remains controversial whether RYGB and SG lead to comparable rates of metabolic improvement and T2DM remission. Some studies report a higher T2DM remission rate or that glycemic targets can be achieved with fewer medications after RYGB compared with SG surgery (3, 22, 23, 32), while others show a similar glycemic outcome for both procedures (12,16,28,46). Data on longterm remission and relapse rates are scarce, but at 3 years, 38% of those after RYGB and 24% of those after SG had a HbA1c Ͻ42 mmol/l (6%) (39). The use ...