title: Gastric bypass surgery, but not caloric restriction, decreases dipeptidyl peptidase-4 activity in obese patients with type 2 diabetes.
abstract: The mechanism by which incretins and their effect on insulin secretion increase markedly following gastric bypass (GBP) surgery is not fully elucidated. We hypothesized that a decrease in the activity of dipeptidyl peptidase-4 (DPP-4), the enzyme which inactivates incretins, may explain the rise in incretin levels post-GBP. Fasting plasma DPP-4 activity was measured after 10-kg equivalent weight loss by GBP (n = 16) or by caloric restriction (CR,n = 14) in obese patients with type 2 diabetes. DPP-4 activity decreased after GBP by 11.6% (p = 0.01), but not after CR. The increased peak glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) response to oral glucose after GBP did not correlate with DPP-4 activity. The decrease in fasting plasma DPP-4 activity after GBP occurred by a mechanism independent of weight loss and did not relate to change in incretin concentrations. Whether the change in DPP-4 activity contributes to improved diabetes control after GBP remains therefore to be determined.
authors.forename: M L
authors.initials: ML
authors.lastname: Alam
authors.forename: B J
authors.initials: BJ
authors.lastname: Van der Schueren
authors.forename: B
authors.initials: B
authors.lastname: Ahren
authors.forename: G C
authors.initials: GC
authors.lastname: Wang
authors.forename: N J
authors.initials: NJ
authors.lastname: Swerdlow
authors.forename: S
authors.initials: S
authors.lastname: Arias
authors.forename: M
authors.initials: M
authors.lastname: Bose
authors.forename: P
authors.initials: P
authors.lastname: Gorroochurn
authors.forename: J
authors.initials: J
authors.lastname: Teixeira
authors.forename: J
authors.initials: J
authors.lastname: McGinty
authors.forename: B
authors.initials: B
authors.lastname: Laferrère
mesh_terms: D000328:Adult; D031204:Caloric Restriction; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism / Q000601:surgery*; D018819:Dipeptidyl Peptidase 4 / Q000378:metabolism*; D005260:Female; D015390:Gastric Bypass / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000601:surgery*; D011446:Prospective Studies
chemical_list: D018819:Dipeptidyl Peptidase 4