Development of techniques for gastrojejunal bypass surgery in obese mice

We have previously described a duodenojejunal bypass (DJB) surgical model in healthy C57BL/6 mice. However, our pilot study showed that the same surgical technique caused a high mortality rate in obese mice. In this study, to significantly improve animal survival rate following bariatric surgery and thereby providing a stable surgical model for the study of glucose homeostasis in obese mice, we have used modified techniques and developed the end-to-side gastrojejunal bypass (GJB) surgery in obese C57BL/6 with impaired glucose tolerance. The modification consisted of using the distal part of the jejunum for biliopancreatic diversion including: 1) ligation of the distal stomach at the level of the pylorus; 2) connection the jejunum to the anterior wall of stomach in an end-to-side fashion; and 3) diverting the biliopancreatic secretions through the blind limb into the distal jejunum through an end-to-side anastomosis. We found that by modifying the proximal end-to-end duodenojejunal anastomosis, described in our original model, to an end-to-side gastrojejunal anastomosis in these obese mice, we were able to significantly improve the postoperative mortality in this study. We have also demonstrated that performing the GJB surgery in obese mice resulted in significant weight loss, normalized blood glucose levels, and prevented acute pancreatitis. This newly developed GJB surgery in the obese mice offers a unique advantage to study the mechanisms of gastrointestinal surgery as treatment for type 2 diabetes.