HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 293/6/G1178    most recent 00295.2007v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Grenier, E. Articles by Levy, E. Search for Related Content PubMed PubMed Citation Articles by Grenier, E. Articles by Levy, E.

INFLAMMATION/IMMUNITY/MEDIATORS

Effect of retinoic acid on cell proliferation and differentiation as well as on lipid synthesis, lipoprotein secretion, and apolipoprotein biogenesis

Departments of ¹Nutrition and ⁴Biochemistry, CHU Sainte-Justine, Université de Montréal, Montreal; ²Group on the Intestinal Epithelium, Canadian Institute of Health Research and Department of Cellular Biology, Faculty of Medicine, Université de Sherbrooke, Sherbrooke; and ³Research Institute, McGill University, Montreal, Quebec, Canada

Submitted 28 June 2007 ; accepted in final form 2 October 2007

Dietary vitamin A and its active metabolites are essential nutrients for many functions as well as potent regulators of gene transcription and growth. Although the epithelium of the small intestine is characterized by rapid and constant renewal and enterocytes play a central role in the absorption and metabolism of alimentary retinol, very little is known about the function of retinoids in the human gastrointestinal epithelium and mechanisms by which programs engage the cell cycle are poorly understood. We have assessed the effects of 10 µM 9- and 13-cis-retinoic acid (RA) on proliferation and differentiation processes, lipid esterification, apolipoprotein (apo) biogenesis and lipoprotein secretion along with nuclear factor gene transcription. Treatment of Caco-2 cells with RA at different concentrations and incubation periods revealed the reduction of thymidine incorporation in 60% preconfluent or 100% confluent cells. Concomitantly, RA 1) modulated D-type cyclins by reducing the mitogen-sensitive cyclin D1 and upregulating cyclin D3 expressions and 2) caused a trend of increase in p38 MAPK, which triggers CDX2, a central protein in cell differentiation. RA remained without effect on lipoprotein output and apo synthesis, even for apo A-I that possesses RARE in its promoter. RA, in combination with 22-hydroxycholesterol, could induce apo A-I gene expression without any impact on apo A-I mass. Only the gene expression of peroxisome proliferator-activated receptor (PPAR)β, retinoic receptor (RAR)β, and RAR was augmented and no alteration was noted in PPAR, PPAR, liver X receptor (LXR), LXRβ, and retinoid X receptors. Taken together, these data highlight RA-induced cell differentiation via specific signaling without a significant impact on apo A-I synthesis.

retinoids; apolipoproteins; lipoproteins; nuclear factors; lipids

This article has been cited by other articles:

				F. Leblond, N. G. Seidah, L.-P. Precourt, E. Delvin, M. Dominguez, and E. Levy Regulation of the proprotein convertase subtilisin/kexin type 9 in intestinal epithelial cells Am J Physiol Gastrointest Liver Physiol, April 1, 2009; 296(4): G805 - G815. [Abstract] [Full Text] [PDF]

				Z. Ravid, M. Bendayan, E. Delvin, A. T. Sane, M. Elchebly, J. Lafond, M. Lambert, G. Mailhot, and E. Levy Modulation of intestinal cholesterol absorption by high glucose levels: impact on cholesterol transporters, regulatory enzymes, and transcription factors Am J Physiol Gastrointest Liver Physiol, November 1, 2008; 295(5): G873 - G885. [Abstract] [Full Text] [PDF]