Effects of gastric bypass and gastric banding on glucose kinetics and gut hormone release.
BACKGROUND
Bariatric surgery markedly improves glucose homeostasis in patients with type 2 diabetes even before any significant weight loss is achieved. Procedures that involve bypassing the proximal small bowel, such as Roux-en-Y gastric bypass (RYGBP), are more efficient than gastric restriction procedures such as gastric banding (GB).


OBJECTIVE
To evaluate the effects of RYGBP and GB on postprandial glucose kinetics and gastro-intestinal hormone secretion after an oral glucose load.


METHODS
This study was a cross-sectional comparison among non-diabetic, weight-stable women who had undergone RYGBP (n = 8) between 9 and 48 months earlier or GB (n = 6) from 25 to 85 months earlier, and weight- and age-matched control subjects (n = 8). The women were studied over 4 h following ingestion of an oral glucose load. Total glucose and meal glucose kinetics were assessed using glucose tracers and plasma insulin, and gut hormone concentrations were simultaneously monitored.


RESULTS
Patients who had undergone RYGBP showed a a more rapid appearance of exogenous glucose in the systemic circulation and a shorter duration of postprandial hyperglycemia than patients who had undergone GB and C. The response in RYGBP patients was characterized by early and accentuated insulin response, enhanced postprandial levels of glucagon-like peptide-1 (GLP-1) and polypeptide YY (PYY), and greater postprandial suppression of ghrelin.


CONCLUSIONS
These findings indicate that RYGBP is associated with alterations in glucose kinetics and glucoregulatory hormone secretion. These alterations are probably secondary to the anatomic rearrangement of the foregut, given the fact that they are not observed after GB. Increased PYY and GLP-1 concentrations and enhanced ghrelin suppression are compatible with reduced food intake after RYGBP.
Rodieux
Frédérique
F
Department of Physiology, University of Lausanne, Lausanne, Switzerland.
Giusti
Vittorio
V
D'Alessio
David A
DA
Suter
Michel
M
Tappy
Luc
L
D000293:Adolescent; D000328:Adult; D050110:Bariatric Surgery; D001786:Blood Glucose / Q000378:metabolism; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004435:Eating / Q000502:physiology; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D015390:Gastric Bypass; D005768:Gastrointestinal Hormones / Q000378:metabolism*; D054439:Ghrelin / Q000097:blood; D052216:Glucagon-Like Peptide 1 / Q000097:blood; D005947:Glucose / Q000378:metabolism*; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D007328:Insulin / Q000097:blood; D008875:Middle Aged; D019894:Peptide YY / Q000097:blood
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D005768:Gastrointestinal Hormones; D054439:Ghrelin; D007328:Insulin; D019894:Peptide YY; D052216:Glucagon-Like Peptide 1; D005947:Glucose