Peptide YY and Glucagon-like Peptide-1 Secretion in Obesity

Objective: The regulation of food intake is disturbed in obesity, possibly resulting from alterations in gut peptide secretion. We hypothesize that obesity is associated with attenuated systemic and tissue concentrations of the gut peptides PYY and GLP-1. Methods: A prospective single-center study in which we included 13 individuals with obesity (BMI 39.5 +/- 2.8 kg/m2) and 11 lean individuals as controls (BMI 20.7 +/- 1.2 kg/m2) matched for age and gender. We measured: (1) tissue concentrations and mRNA expression of GLP-1 and PYY in ileal and colonic biopsies taken during routine colonoscopy and (2) plasma concentrations of PYY and GLP-1 in response to a meal in the same group. Results: Plasma GLP-1 and PYY responses did not differ between individuals with obesity and lean controls. Neither were tissue concentrations and mRNA expression of both peptides different between both groups. Conclusions: Systemic and local PYY and GLP-1 concentrations in individuals with obesity do not differ from those in lean subjects.