Abstract
Context:
The combination of peptide YY (PYY) and glucagon-like peptide-1 (GLP-1) has been proposed as a potential treatment for diabetes and obesity. However, the combined effects of these hormones, PYY3-36 and GLP-17-36 amide, on glucose homeostasis are unknown.
Objective:
This study sought to investigate the acute effects of PYY3-36 and GLP-17-36 amide, individually and in combination, on insulin secretion and sensitivity.
Setting and Design:
Using a frequently sampled iv glucose tolerance test (FSIVGTT) and minimal modeling, this study measured the effects of PYY3-36 alone, GLP-17-36 amide alone, and a combination of PYY3-36 and GLP-17-36 amide on acute insulin response to glucose (AIRg) and insulin sensitivity index (S-I) in 14 overweight human volunteers, studied in a clinical research facility.
Results:
PYY3-36 alone caused a small but nonsignificant increase in AIRg. GLP-17-36 amide alone and the combination of PYY3-36 and GLP-17-36 amide did increase AIRg significantly. No significant differences in SI were observed with any intervention.
Conclusions:
PYY3-36 lacks any significant acute effects on first-phase insulin secretion or SI when tested using an FSIVGTT. Both GLP-17-36 amide alone and the combination of PYY3-36 and GLP-17-36 amide increase first-phase insulin secretion. There does not seem to be any additive or synergistic effect between PYY3-36 and GLP-17-36 amide on first-phase insulin secretion. Neither hormone alone nor the combination had any significant effects on SI.