Regulation of sucrase-isomaltase and hexose transporters in caco-2
cells: a role for cytochrome p450 1a1?.
Carri[grave]ere, V[acute]eronique, Alain Barbat, Monique Rousset,
Edith Brot-Laroche, Elisabeth Dussaulx, Dani[grave]ele Cambier,
Isabelle De Waziers, Philippe Beaune, and Alain Zweibaum.
Unit[acute]e de Recherches sur la Diff[acute]erenciation Cellulaire
Intestinale, INSERM U178, 16 avenue Paul-Vaillant-Couturier 94807
Villejuif Cedex, France, and Unit[acute]e de Recherches de Biochimie
Pharmacologique et M[acute]etabolique, INSERM U75, Centre Hospitalo
-Universitaire Necker-Enfants Malades, 156 rue de Vaugirard, 75730
Paris Cedex 15, France
APStracts 2:0254G, 1995.
Involvement of CYP1A1 in the regulation of sucrase-isomaltase and
hexose transporters was analyzed in low- (TC7) and high- (PF11)
glucose consuming Caco-2 clones. CYP1A1 mRNA is elevated in
exponentially growing cells, concomitantly with high rates of glucose
consumption and high levels of GLUT1 and GLUT3 mRNA. After confluency
CYP1A1 is not detectable in TC7 cells, this being associated with a
decreased glucose consumption, a downregulation of GLUT1 and GLUT3,
and an upregulation of sucrase-isomaltase, SGLT1, GLUT2 and GLUT5. In
PF11 cells CYP1A1 mRNA remains elevated, along with high glucose
consumption, high levels of GLUT1 and GLUT3 and minimal expression of
sucrase-isomaltase, SGLT1, GLUT2 and GLUT5. Exposure of TC7 cells to
inducers of CYP1A1 results in high levels of CYP1A1 mRNA, a tenfold
increase of glucose consumption after confluency, an upregulation of
GLUT1 and GLUT3 and a downregulation of sucrase-isomaltase, GLUT2,
and to a lower extent SGLT1 and GLUT5. These results suggest that
activation of CYP1A1, whether spontaneous or drug-induced, is
involved in the variations of glucose utilization and in the
associated modifications of expression of sucrase-isomaltase and
hexose transporters.
Received 14 August 1995; accepted in final form 30 Novmeber 1995.
APS Manuscript Number G350-5.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 12 December 95