Abstract
BACKGROUND: Expression and function of hexose transporters vary diurnally in rat small intestine; however, this subject remains unexplored in mice. AIM: The aim of the study was to investigate the diurnal expression and function of hexose transporters SGLT1, GLUT2, and GLUT5 in mouse small bowel. METHODS: Twenty-four c57bl6 mice maintained in a 12-h light/dark room (6 AM: -6 PM: ) were sacrificed at 9 AM: , 3 PM: , 9 PM: , and 3 AM: (n = 6 each). In duodenal, jejunal, and ileal mucosa, total cellular mRNA and protein levels were quantitated by real-time PCR and semiquantitative Western blotting, respectively. The everted sleeve technique measured transporter-mediated glucose uptake at 9 AM: and 9 PM: . RESULTS: mRNA expression of SGLT1, GLUT2, and GLUT5 varied diurnally in all three intestinal segments (p 70% of food intake occurred; glucose transport followed a similar pattern with increased uptake at 9 PM: . CONCLUSION: Hexose transporter expression and function vary diurnally with nocturnal feeding patterns of mice.