Article
Challenging the foregut hypothesis – Remission of Type 2 Diabetes after Roux-en Y Gastric Bypass but not after Duodeno-Jejunal Bypass in genetically diabetic rats
Search Medline for
Authors
Published: | April 26, 2013 |
---|
Outline
Text
Introduction: Bariatric surgery is currently the most effective therapeutic option to treat type 2 diabetes mellitus (T2DM) associated with morbid obesity, but the underlying mechanisms remain unclear. Roux-en-Y Gastric Bypass (RYGB) and Duodenal-Jejunal Bypass (DJB) bypass the proximal small intestine, but only RYGB is known to reduce food intake and body weight. We aimed to investigate the immediate, short and midterm effects of RYGB and DJB on glucose control.
Material and methods: Male ZDF fa/fa rat, aged 12 weeks (339 ± 21g), were randomized to either RYGB (n=18), DJB (n=16), sham procedure (n=15) or no intervention (n=10). Age and bodyweight matched ZDF fa/+ animals (n=10) were used as nondiabetic controls. Food intake and body weight were recorded daily. Animals were Fasting Glucose, Insulin, HOMA and gut hormones (GLP-1 and PYY) were measured at baseline and postoperative day 2, 10 and 35. An oral Glucose tolerance test (OGTT) was performed on postoperative days 12 and 26.
Results: RYGB ZDF fa/fa rats lost weight immediately after surgery and weighed less than all other groups (postoperative day 35, p<0.001). Daily food intake was consistently lower after RYGB (p<0.001), but not after DJB, in comparison to all other groups. Fasting glucose, insulin and HOMA were not different after RYGB compared to nondiabetic ZDF fa/+ controls (p>0.05), while fasting glucose (p<0.001), insulin (p<0.05) and HOMA (p<0.001) remained higher after DJB. RYGB rats showed reduced glucose responses during an oral glucose tolerance test compared to DJB and sham-operated ZDF fa/fa rats (p<0.001). There were no conclusive differences in fasting GLP-1 and PYY levels between ZDF fa/fa rats that received RYGB or DJB surgery.
Conclusion: These data suggest that changes in the enteroendocrine axis alone are not sufficient for improved glycaemic control after DJB or RYGB, but that reduced caloric intake and body weight loss after RYGB might play an important role.