Sleeve gastrectomy improves glucose homeostasis in Zucker diabetic fatty rats

Background: Bariatric surgery improves glucose homeostasis, but the mechanism of action is poorly understood. The aim of this study was to assess the effect of sleeve gastrectomy (SG) on glucose homeostasis in two obese populations of rats. Methods: Two strains of rats [Zucker fatty (ZF) and Zucker diabetic fatty (ZDF)] were each divided into two groups: sham and SG. Food intake was measured daily, and weight was measured bi-weekly. Oral glucose tolerance testing (OGTT) was performed before and 45 days after surgery. Results: In both strains of rats, there was no statistical difference in food intake and weight gain between the sham and SG rodents before and after surgery. In ZF rats, there was no change in fasting glucose or OGTT area under the curve (AUC) before or 45 days after surgery. In the ZDF rodents, the mean preoperative fasting glucose and OGTT AUC was 204±25 and 25,441±2,648, respectively. At 45 days after surgery, mean fasting glucose significantly increased in the sham (sham=529±26, p=0.0003) but not in the SG rodents (SG=289±46, p=0.1113). In ZDF sham animals, OGTT at 45 days showed a higher AUC compared to before surgery (44,983±6,338, p=0.006), whereas in ZDF SG rodents, the increase in AUC glucose approached but did not reach statistical significance (35,553±3,925, p=0.06). Conclusions: In ZF and ZDF rodents, SG did not influence food intake and weight evolution. In ZDF rodents, diabetes progressed in the sham group but not in the SG group.