Effects of rectal administration of taurocholic acid on glucagon‐like peptide‐1 and peptide YY secretion in healthy humans

Glucagon‐like peptide‐1 ( GLP ‐1) and peptide YY ( PYY ), secreted by enteroendocrine L‐cells located most densely in the colon and rectum, are of fundamental importance in blood glucose and appetite regulation. In animal models, colonic administration of bile acids can stimulate GLP ‐1 and PYY by TGR5 receptor activation. We evaluated the effects of taurocholic acid ( TCA ), administered as an enema, on plasma GLP ‐1 and PYY , as well as gastrointestinal sensations in 10 healthy male subjects, and observed that rectal administration of TCA promptly stimulated secretion of both GLP ‐1 and PYY , and increased fullness, in a dose‐dependent manner. These observations confirm that topical application of bile acids to the distal gut may have potential for the management of type 2 diabetes and obesity.