Pancreatic polypeptide - a potential biomarker of GIP receptor activation in vivo.

The insulinotropic gut hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) are key factors in the regulation of normal postprandial glucose homeostasis, but in most reports, the glucose-lowering effect of GIP has been shown to be blunted or even absent in people with type 2 diabetes (T2D) (1). Despite previous reports that GIP does not potentiate the glucose-lowering effect of GLP-1 in type 2 diabetes (2), a dual GIP/GLP-1 receptor agonist (tirzepatide/LY3298176) has recently been reported to reduce HbA1c and body weight in overweight/obese individuals with type 2 diabetes beyond that of GLP-1 receptor monoagonism (dulaglutide) (3).