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: M500523-JLR200v1 47/6/1261    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal 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 Google Scholar Google Scholar Articles by Anwar, K. Articles by Hussain, M. M. Search for Related Content PubMed PubMed Citation Articles by Anwar, K. Articles by Hussain, M. M. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol. 47, 1261-1273, June 2006
Copyright © 2006 by American Society for Biochemistry and Molecular Biology

Transport of vitamin E by differentiated Caco-2 cells

Kamran Anwar^*, Herbert J. Kayden and M. Mahmood Hussain^1,*

^* Departments of Anatomy & Cell Biology and Pediatrics, State University of New York Downstate Medical Center, Brooklyn, NY
New York University Medical Center, New York, NY

Published, JLR Papers in Press, March 28, 2006.

¹ To whom correspondence should be addressed. e-mail: mahmood.hussain{at}downstate.edu

In hepatocytes, vitamin E is secreted via the efflux pathway and is believed to associate with apolipoprotein B (apoB)-lipoproteins extracellularly. The molecular mechanisms involved in the uptake, intracellular trafficking, and secretion of dietary vitamin E by the intestinal cells are unknown. We observed that low concentrations of Tween-40 were better for the solubilization and delivery of vitamin E to differentiated Caco-2 cells, whereas high concentrations of Tween-40 and sera inhibited this uptake. Vitamin E uptake was initially rapid and then reached saturation. Subcellular localization revealed that vitamin E primarily accumulated in microsomal membranes. Oleic acid (OA) treatment, which induces chylomicron assembly and secretion, decreased microsomal membrane-bound vitamin E in a time-dependent manner. To study secretion, differentiated Caco-2 cells were pulse-labeled with vitamin E and chased in the presence and absence of OA. In the absence of OA, vitamin E was associated with intestinal high density lipoprotein (I-HDL), whereas OA-treated cells secreted vitamin E with I-HDL and chylomicrons. No extracellular transfer of vitamin E between these lipoproteins was observed. Glyburide, an antagonist of ABCA1, partially inhibited its secretion with I-HDL, whereas plasma HDL increased vitamin E efflux. An antagonist of microsomal triglyceride transfer protein, brefeldin A, and monensin specifically inhibited vitamin E secretion with chylomicrons. These studies indicate that vitamin E taken up by Caco-2 cells is stored in the microsomal membranes and secreted with chylomicrons and I-HDL. Transport via I-HDL might contribute to vitamin E absorption in patients with abetalipoproteinemia receiving large oral doses of the vitamin.

Supplementary key words microsomal triglyceride transfer protein • lipoprotein assembly • triglycerides • cholesteryl esters • phospholipids • triacylglycerol • apolipoprotein B • tocopherol • abetalipoproteinemia

Abbreviations: apoB, apolipoprotein B; I-HDL, intestinal high density lipoprotein; MTP, microsomal triglyceride transfer protein; OA, oleic acid; SFM, serum-free medium; TC, taurocholate; TTP, -tocopherol transfer protein

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				D. Cheng, J. Iqbal, J. Devenny, C.-H. Chu, L. Chen, J. Dong, R. Seethala, W. J. Keim, A. V. Azzara, R. M. Lawrence, et al. Acylation of Acylglycerols by Acyl Coenzyme A:Diacylglycerol Acyltransferase 1 (DGAT1): FUNCTIONAL IMPORTANCE OF DGAT1 IN THE INTESTINAL FAT ABSORPTION J. Biol. Chem., October 31, 2008; 283(44): 29802 - 29811. [Abstract] [Full Text] [PDF]

				J. Iqbal, L. L. Rudel, and M. M. Hussain Microsomal Triglyceride Transfer Protein Enhances Cellular Cholesteryl Esterification by Relieving Product Inhibition J. Biol. Chem., July 18, 2008; 283(29): 19967 - 19980. [Abstract] [Full Text] [PDF]

				O. Kenny, Y. O'Callaghan, and N.M. O'Brien Effects of Ingredient Incorporation into Sausage Meat on the Micellarisation and uptake of {alpha}-tocopherol by Caco-2 Human Intestinal Cells Food Science and Technology International, February 1, 2008; 14(1): 79 - 86. [Abstract] [PDF]

				A. During and E. H. Harrison Mechanisms of provitamin A (carotenoid) and vitamin A (retinol) transport into and out of intestinal Caco-2 cells J. Lipid Res., October 1, 2007; 48(10): 2283 - 2294. [Abstract] [Full Text] [PDF]

				K. Anwar, J. Iqbal, and M. M. Hussain Mechanisms involved in vitamin E transport by primary enterocytes and in vivo absorption J. Lipid Res., September 1, 2007; 48(9): 2028 - 2038. [Abstract] [Full Text] [PDF]

				X. Pan, F. N. Hussain, J. Iqbal, M. H. Feuerman, and M. M. Hussain Inhibiting Proteasomal Degradation of Microsomal Triglyceride Transfer Protein Prevents CCl4-induced Steatosis J. Biol. Chem., June 8, 2007; 282(23): 17078 - 17089. [Abstract] [Full Text] [PDF]

				S. Fatma, R. Yakubov, K. Anwar, and M. M. Hussain Pluronic L81 enhances triacylglycerol accumulation in the cytosol and inhibits chylomicron secretion J. Lipid Res., November 1, 2006; 47(11): 2422 - 2432. [Abstract] [Full Text] [PDF]