| First Author | Zukerman S | Year | 2013 |
| Journal | Am J Physiol Regul Integr Comp Physiol | Volume | 305 |
| Issue | 7 | Pages | R840-53 |
| PubMed ID | 23926132 | Mgi Jnum | J:201615 |
| Mgi Id | MGI:5514466 | Doi | 10.1152/ajpregu.00297.2013 |
| Citation | Zukerman S, et al. (2013) Post-oral appetite stimulation by sugars and nonmetabolizable sugar analogs. Am J Physiol Regul Integr Comp Physiol 305(7):R840-53 |
| abstractText | Post-oral sugar actions enhance the intake of and preference for sugar-rich foods, a process referred to as appetition. Here, we investigated the role of intestinal sodium glucose cotransporters (SGLTs) in sugar appetition in C57BL/6J mice using sugars and nonmetabolizable sugar analogs that differ in their affinity for SGLT1 and SGLT3. In experiments 1 and 2, food-restricted mice were trained (1 h/day) to consume a flavored saccharin solution [conditioned stimulus (CS-)] paired with intragastric (IG) self-infusions of water and a different flavored solution (CS+) paired with infusions of 8 or 12% sugars (glucose, fructose, and galactose) or sugar analogs (alpha-methyl-d-glucopyranoside, MDG; 3-O-methyl-d-glucopyranoside, OMG). Subsequent two-bottle CS+ vs. CS- choice tests were conducted without coinfusions. Infusions of the SGLT1 ligands glucose, galactose, MDG, and OMG stimulated CS+ licking above CS- levels. However, only glucose, MDG, and galactose conditioned significant CS+ preferences, with the SGLT3 ligands (glucose, MDG) producing the strongest preferences. Fructose, which is not a ligand for SGLTs, failed to stimulate CS+ intake or preference. Experiment 3 revealed that IG infusion of MDG+phloridzin (an SGLT1/3 antagonist) blocked MDG appetition, whereas phloridzin had minimal effects on glucose-induced appetition. However, adding phloretin (a GLUT2 antagonist) to the glucose+phloridzin infusion blocked glucose appetition. Taken together, these findings suggest that humoral signals generated by intestinal SGLT1 and SGLT3, and to a lesser degree, GLUT2, mediate post-oral sugar appetition in mice. The MDG results indicate that sugar metabolism is not essential for the post-oral intake-stimulating and preference-conditioning actions of sugars in mice. |
