TY - JOUR
T1 - Hexose transporter expression and function in mouse small intestine
T2 - Role of diurnal rhythm
AU - Fatima, Javairiah
AU - Iqbal, Corey W.
AU - Houghton, Scott G.
AU - Kasparek, Michael S.
AU - Duenes, Judith A.
AU - Zheng, Ye
AU - Sarr, Michael G.
N1 - Funding Information:
Presented in part at Academic Surgical Congress in Phoenix, Arizona (Feb 7, 2007) and published in abstract form in Journal of Surgical Research (2007;137:255–256). This work was supported in part by the National Institutes of Health (Grant DK 39337-MGS). J.Fatima.C.W.Iqbal.S.G.Houghton.M.S.Kasparek. J. A. Duenes.Y. Zheng.M. G. Sarr (*) Gastroenterology Research Unit (GU 1001), Department of Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA e-mail: Sarr.Michael@mayo.edu
PY - 2009/4
Y1 - 2009/4
N2 - 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∈ ∈0.03). SGLT1, GLUT2, and GLUT5 protein levels varied diurnally in duodenum and jejunum (p∈<∈0.05) but not in ileum. Transporter-mediated glucose uptake was greater at 9 pm than 9 am (p∈ ∈0.04) in all three segments. V max was greater in duodenum (10 vs 6 nmol/cm/s) and jejunum (8 vs 5 nmol/cm/s) at 9 pm compared to 9 am (p∈=∈0.01); K m remained unchanged. Summary: mRNA levels of intestinal hexose transporters varied diurnally. Protein levels peaked 6-12 h later during dark cycle when >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.
AB - 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∈ ∈0.03). SGLT1, GLUT2, and GLUT5 protein levels varied diurnally in duodenum and jejunum (p∈<∈0.05) but not in ileum. Transporter-mediated glucose uptake was greater at 9 pm than 9 am (p∈ ∈0.04) in all three segments. V max was greater in duodenum (10 vs 6 nmol/cm/s) and jejunum (8 vs 5 nmol/cm/s) at 9 pm compared to 9 am (p∈=∈0.01); K m remained unchanged. Summary: mRNA levels of intestinal hexose transporters varied diurnally. Protein levels peaked 6-12 h later during dark cycle when >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.
KW - Diurnal rhythm
KW - Hexose transporters
KW - Mice
KW - Small intestine
KW - Sugar absorption
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U2 - 10.1007/s11605-008-0776-4
DO - 10.1007/s11605-008-0776-4
M3 - Article
C2 - 19082670
AN - SCOPUS:67349192167
VL - 13
SP - 634
EP - 641
JO - Journal of Gastrointestinal Surgery
JF - Journal of Gastrointestinal Surgery
SN - 1091-255X
IS - 4
ER -