Gastric Bypass Surgery in Mice Does Not Change Islet Size nor Composition

Research output: Contribution to journalPublished meeting abstract


Gastric bypass surgery improves type 2 diabetes, but the weight loss independent mechanisms remain elusive. We set out to unravel a potential benefi cial role of gastric bypass surgery on islets of Langerhans. Eight week old male C57Bl/6 mice were fed a high fat diet (60% kcal fat) for 14 weeks and subsequently subjected to Roux-en-Y gastric bypass (RYGB; n=16). Weight matched (WMS; n=13) and pair fed sham operated mice (PFS; n=14) were used as controls. 8 weeks post-surgery, mice were phenotyped by intraperitoneal glucose tolerance test (IPGTT) and indirect calorimetry. Pancreatic tissue was analyzed by immunohistochemistry. Eight weeks after surgery, RYGB and WMS mice showed abundant weight loss, decreased fasting glucose and insulin levels, as well as improved glucose tolerance as compared to obese PFS mice (Table 1). Additionally, energy expenditure was higher in RYGB (2022 ± 145 kJ/day) as compared to WMS (1756 ± 284 kJ/day, P < 0.05) and PFS (1863 ± 195 kJ/day, P 0.11). Pancreatic islet size, as well as insulin, glucagon and somatostatin positive area per islet were similar between all groups. In summary, RYGB surgery improves glucose homeostasis and increases energy expenditure, but has no effect on size or cell composition of islets of Langerhans. As improved beta cell function has been reported after RYGB, RNA-Seq analysis of isolated islets is currently ongoing in order to reveal the underlying molecular mechanisms.


  • Roman Vangoitsenhoven
  • Michael Maris
  • Joao Paulo da Cunha
  • Matthias Lannoo
  • Lut Overbergh
  • Chantal Mathieu
  • Bart Van der Schueren
External organisations
  • University Hospitals Leuven
  • Catholic University of Leuven
Original languageEnglish
Pages (from-to)A550
Issue numberSuppl 1
Publication statusPublished - 2015
Publication categoryResearch
Externally publishedYes
Event75th Scientific Sessions of the American Diabetes Association - Boston, United States
Duration: 2015 Jun 52015 Jun 9