Evaluating the mechanisms of improved glucose homeostasis after bariatric surgery in ossabaw miniature swine

Jonathan G. Sham, Vlad V. Simianu, Andrew S. Wright, Skye D. Stewart, Mouhamad Alloosh, Michael Sturek, David E. Cummings, David R. Flum

Research output: Contribution to journalArticlepeer-review

9 Scopus citations


Background. Roux-en-Y gastric bypass (RYGB) is the most common bariatric operation; however, the mechanism underlying the profound weight-independent effects on glucose homeostasis remains unclear. Large animal models of naturally occurring insulin resistance (IR), which have been lacking, would provide opportunities to elucidate such mechanisms. Ossabaw miniature swine naturally exhibit many features that may be useful in evaluating the anti diabetic effects of bariatric surgery. Methods. Glucose homeostasis was studied in 53 Ossabaw swine. Thirty-two received an obesogenic diet and were randomized to RYGB, gastrojejunostomy (GJ), gastrojejunostomy with duodenal exclusion (GJD), or Sham operations. Intravenous glucose tolerance tests and standardized meal tolerance tests were performed prior to, 1, 2, and 8 weeks after surgery and at a single time-point for regular diet control pigs. Results. High-calorie-fed Ossabaws weighed more and had greater IR than regular diet controls, though only 70% developed IR. All operations caused weight-loss-independent improvement in IR, though only in pigs with high baseline IR. Only RYGB induced weight loss and decreased IR in the majority of pigs, as well as increasing AUCinsulin/AUCglucose. Conclusions. Similar to humans, Ossabaw swine exhibit both obesity-dependent and obesity-independent IR. RYGB promoted weight loss, IR improvement, and increased AUCinsulin/AUCglucose, compared to the smaller changes following GJ and GJD, suggesting a combination of upper and lower gut mechanisms in improving glucose homeostasis.

Original languageEnglish (US)
Article number526972
JournalJournal of Diabetes Research
StatePublished - 2014

Bibliographical note

Publisher Copyright:
© 2014 Jonathan G. Sham et al.


Dive into the research topics of 'Evaluating the mechanisms of improved glucose homeostasis after bariatric surgery in ossabaw miniature swine'. Together they form a unique fingerprint.

Cite this