The Effects of Antral Preservation and Antral Resection on Body Composition, Glycemic Control and Bone Mineral Density Following Vertical Sleeve Gastrectomy in C57BL/6J Mice with Obesity and Type 2 Diabetes

PURPOSE: Sleeve gastrectomy (SG) is the most currently popular operation for obesity and related metabolic disorders. The aim of this study was to compare the effect of antrum preservation SG (AP-SG) and antrum resection SG (AR-SG) on the body composition, glycemic control and bone mineral density (BMD) in mice. METHODS: Sham, AP-SG and AR-SG operation were performed on obese and T2D C57BL/6J mice (8 in each group). Body weight, food intake, and fasting glucose (FG) levels were measured at the 0, 2, 4, 6 and 8 weeks post-operatively. Oral glucose tolerance test (OGTT) was performed preoperatively and at the eighth postoperative week. The body fat content and total body BMD were evaluated by dual-energy x-ray absorptiometry. After being euthanized, the femurs were harvested and analyzed by micro-CT. RESULTS: The improvements in body weight, food intake, FG, glycemic control and body fat were statistically significant following AP-SG and AR-SG. Both AP-SG and AR-SG groups decreased total body BMD and regional BMD in the distal femur compared to the sham group. No significant difference of FG was observed in AP-SG and AR-SG group postoperatively, but AR-SG showed significantly superior OGTT glucose AUC than AP-SG. Except for a lower BMD, AR-SG achieved superior outcomes in body fat and glycemic control than AP-SG. CONCLUSION: Antrum resection SG shows a lower percentage of body fat and better glycemic control than antrum preservation SG. However, antrum resection SG has a higher risk of having a lower bone mass. Further human clinical trials are needed to confirm this finding.