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

This Article Full Text (PDF) 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 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 Bettendorff, L. Articles by Wins, P. Search for Related Content PubMed PubMed Citation Articles by Bettendorff, L. Articles by Wins, P. Social Bookmarking                      What's this?

J. Biol. Chem., Vol. 269, Issue 20, 14379-14385, May, 1994

Mechanism of thiamine transport in neuroblastoma cells. Inhibition of a high affinity carrier by sodium channel activators and dependence of thiamine uptake on membrane potential and intracellular ATP

L Bettendorff and P Wins
Laboratory of General and Comparative Biochemistry, University of Liege, Belgium.

Nerve cells are particularly sensitive to thiamine deficiency. We studied thiamine transport in mouse neuroblastoma (Neuro 2a) cells. At low external concentration, [14C]thiamine was taken up through a saturable high affinity mechanism (Km = 35 nM). This was blocked by low concentrations of the Na+ channel activators veratridine (IC50 = 7 +/- 4 microM) and batrachotoxin (IC50 = 0.9 microM). These effects were not antagonized by tetrodotoxin and were also observed in cell lines devoid of Na+ channels, suggesting that these channels are not involved in the mechanism of inhibition. At high extracellular concentrations, thiamine uptake proceeds essentially via a low affinity carrier (Km = 0.8 mM), insensitive to veratridine but blocked by divalent cations. In both cases, the uptake was independent on external sodium, partially inhibited (10-35%) by depolarization and sensitive to metabolic inhibitors. A linear relationship between the rate of thiamine transport and intracellular ATP concentration was found. When cells grown in a medium of low thiamine concentration (6 nM) were exposed to 100 nM extracellular thiamine, a 3-fold increase in intracellular thiamine diphosphate was observed after 2 h while the concomitant increase in intracellular free thiamine was barely significant. These data suggest a secondary active transport of thiamine, the main driving force being thiamine phosphorylation rather than the sodium gradient.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				B. Ashokkumar, N. D. Vaziri, and H. M. Said Thiamin uptake by the human-derived renal epithelial (HEK-293) cells: cellular and molecular mechanisms Am J Physiol Renal Physiol, October 1, 2006; 291(4): F796 - F805. [Abstract] [Full Text] [PDF]

				L. de Jong, Y. Meng, J. Dent, and S. Hekimi Thiamine Pyrophosphate Biosynthesis and Transport in the Nematode Caenorhabditis elegans Genetics, October 1, 2004; 168(2): 845 - 854. [Abstract] [Full Text] [PDF]

				M. E. Schweingruber The Melaminophenyl Arsenicals Melarsoprol and Melarsen Oxide Interfere with Thiamine Metabolism in the Fission Yeast Schizosaccharomyces pombe Antimicrob. Agents Chemother., September 1, 2004; 48(9): 3268 - 3271. [Abstract] [Full Text] [PDF]

				B. Lakaye, A. F. Makarchikov, A. F. Antunes, W. Zorzi, B. Coumans, E. De Pauw, P. Wins, T. Grisar, and L. Bettendorff Molecular Characterization of a Specific Thiamine Triphosphatase Widely Expressed in Mammalian Tissues J. Biol. Chem., April 12, 2002; 277(16): 13771 - 13777. [Abstract] [Full Text] [PDF]

				P. K. Dudeja, S. Tyagi, R. J. Kavilaveettil, R. Gill, and H. M. Said Mechanism of thiamine uptake by human jejunal brush-border membrane vesicles Am J Physiol Cell Physiol, September 1, 2001; 281(3): C786 - C792. [Abstract] [Full Text] [PDF]

				H. M. Said, A. Ortiz, V. S. Subramanian, E. J. Neufeld, M. P. Moyer, and P. K. Dudeja Mechanism of thiamine uptake by human colonocytes: studies with cultured colonic epithelial cell line NCM460 Am J Physiol Gastrointest Liver Physiol, July 1, 2001; 281(1): G144 - G150. [Abstract] [Full Text] [PDF]

				K. Nosaka, M. Onozuka, H. Nishino, H. Nishimura, Y. Kawasaki, and H. Ueyama Molecular Cloning and Expression of a Mouse Thiamin Pyrophosphokinase cDNA J. Biol. Chem., November 26, 1999; 274(48): 34129 - 34133. [Abstract] [Full Text] [PDF]

				B. Dutta, W. Huang, M. Molero, R. Kekuda, F. H. Leibach, L. D. Devoe, V. Ganapathy, and P. D. Prasad Cloning of the Human Thiamine Transporter, a Member of the Folate Transporter Family J. Biol. Chem., November 5, 1999; 274(45): 31925 - 31929. [Abstract] [Full Text] [PDF]

				H. M. Said, A. Ortiz, C. K. Kumar, N. Chatterjee, P. K. Dudeja, and S. Rubin Transport of thiamine in human intestine: mechanism and regulation in intestinal epithelial cell model Caco-2 Am J Physiol Cell Physiol, October 1, 1999; 277(4): C645 - C651. [Abstract] [Full Text] [PDF]

				P. V. Blair, R. Kobayashi, H. M. Edwards, N. F. Shay, D. H. Baker, and R. A. Harris Dietary Thiamin Level Influences Levels of Its Diphosphate Form and Thiamin-Dependent Enzymic Activities of Rat Liver J. Nutr., March 1, 1999; 129(3): 641 - 648. [Abstract] [Full Text]

				R. Zhao, F. Gao, and I. D. Goldman Reduced folate carrier transports thiamine monophosphate: an alternative route for thiamine delivery into mammalian cells Am J Physiol Cell Physiol, June 1, 2002; 282(6): C1512 - C1517. [Abstract] [Full Text] [PDF]