Importance of small bowel peptides for the improved glucose metabolism 20 years after jejunoileal bypass for obesity.
BACKGROUND
Obese patients operated with jejunoileal bypass (JIB) have reduced plasma concentrations of insulin and glucose. Gastric inhibitory peptide/glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide-1 (GLP-1) have been found to have a profound incretin effect in humans. The aim of the present study was to examine the long-term effect of JIB on glucose metabolism.


METHODS
Four groups (lean, nonoperated obese, obese 9 months after JIB and obese 20 years after JIB) of six females each were given a mixed meal (280 kcal). Plasma samples were obtained every 10 min for 60 min postprandially and were analyzed for glucose, insulin, GIP and GLP-1.


RESULTS
A reduction in body mass index (kg/m2) was seen for the two patient groups operated with JIB (12.1, at 9 months post-op; 13.1, at 20 years post-op). Surgery by JIB resulted in a reduction of glucose and insulin values. Concomitantly there was an elevation of postprandial GIP and GLP-1 plasma concentrations. In the obese subjects 20 years after JIB both fasting and postprandial GIP and GLP-1 values were markedly elevated compared with the other three groups; and plasma glucose and insulin concentrations were maintained at normal levels.


CONCLUSIONS
The improvement in glucose metabolism seen after JIB may be due to reduced insulin resistance after weight loss and/or increased levels of the incretin hormones GIP and GLP-1. Progressively, elevated levels of GIP and GLP-1 seem to be necessary to maintain glucose homeostasis at long-term follow-up after this procedure.
Näslund
E
E
Department of Surgery, Karolinska Institute, Stockholm, Sweden. erik.naslund@kir.ds.sll.se
Backman
L
L
Holst
J J
JJ
Theodorsson
E
E
Hellström
P M
PM
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D005749:Gastric Inhibitory Polypeptide / Q000378:metabolism; D005934:Glucagon / Q000378:metabolism; D052216:Glucagon-Like Peptide 1; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007421:Intestine, Small / Q000378:metabolism*; D007581:Jejunoileal Bypass; D008875:Middle Aged; D010446:Peptide Fragments / Q000378:metabolism; D019518:Postprandial Period; D011498:Protein Precursors / Q000378:metabolism; D013997:Time Factors; D015431:Weight Loss
D001786:Blood Glucose; D007328:Insulin; D010446:Peptide Fragments; D011498:Protein Precursors; D005749:Gastric Inhibitory Polypeptide; D052216:Glucagon-Like Peptide 1; D005934:Glucagon; D005947:Glucose