Steviol Glycoside Rebaudioside A Induces Glucagon-like Peptide-1 and Peptide YY Release in a Porcine ex Vivo Intestinal Model

Glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) are hormones important for satiation and are involved in the process called ileal brake. The aim of this study was to investigate the GLP-1- and PYY-stimulating efficacy of rebaudioside A, casein, and sucrose. This was studied using tissue segments collected from various regions of the pig small intestine. GLP-1 release was strongest from the distal ileum. There, control release was 0.06 +/- 0.01 (GLP-1) and 0.07 +/- 0.01 (PYY) pmol/cm(2) of tissue. Rebaudioside A (2.5, 12.5, and 25 mM) stimulated GLP-1 release (0.14 +/- 0.02, 0.16 +/- 0.02, and 0.13 +/- 0.02 pmol/cm(2) of tissue, p < 0.001) and PYY release (0.19 +/- 0.02, 0.42 +/- 0.06, and 0.27 +/- 0.03 pmol/cm2 of tissue, p < 0.001). Sucrose stimulated GLP-1 release (0.08 +/- 0.01 pmol/cm2 of tissue, p < 0.05) only at 10 mM. Casein (0.5%, 1%, and 2.5%, w/v) stimulated GLP-1 release (0.15 +/- 0.03, 0.13 +/- 0.02, and 0.14 +/- 0.01 pmol/cm(2) of tissue, p < 0.001) and PYY release (0.13 +/- 0.02, 0.20 +/- 0.03, and 0.27 +/- 0.03 pmol/cm(2) of tissue, p < 0.01). These findings may help in developing dietary approaches for weight management.