QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted 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 Daberkow, R. L. Articles by Zempleni, J. Search for Related Content PubMed PubMed Citation Articles by Daberkow, R. L. Articles by Zempleni, J.

---

Biochemical and Molecular Actions of Nutrients
Research Communication

Monocarboxylate Transporter 1 Mediates Biotin Uptake in Human Peripheral Blood Mononuclear Cells¹

Rachel L. Daberkow^*, Brett R. White, Rebecca A. Cederberg, Jacob B. Griffin^* and Janos Zempleni^*,,**,2

Departments of ^* Nutritional Science and Dietetics, Animal Science and ^** Biochemistry, University of Nebraska at Lincoln, Lincoln, NE

²To whom correspondence should be addressed. E-mail: jzempleni2{at}unl.edu.

Here the hypothesis was tested that monocarboxylate transporters (MCT) mediate biotin transport in human lymphoid cells. Uptake of [³H]biotin was measured in human lymphoid cells [peripheral blood mononuclear cells (PBMC) and Jurkat cells] under conditions known to affect MCT-mediated transport. When biotin uptake into PBMC was measured in the presence of excess concentrations of competitors (MCT substrates) and MCT inhibitors, transport rates decreased significantly to <75 and <67%, respectively, of controls. Biotin uptake correlated with the concentration of protons in culture media, consistent with cotransport of protons and the carboxylate biotin by MCT. Efflux of biotin from PBMC was stimulated by extracellular lactate (a known substrate for MCT), consistent with countertransport of the two substrates by the same transporter. PBMC responded to proliferation with parallel increases of transport rates for both biotin and lactate, providing circumstantial evidence that the same transporter mediates uptake of the two substrates in PBMC. Transfection of Jurkat cells with an expression vector encoding MCT1 caused a 50% increase in biotin uptake; in contrast, overexpression of MCT1 did not affect biotin uptake in various nonlymphoid cell lines. These findings are consistent with the hypothesis that MCT mediate biotin uptake in human lymphoid cells.

KEY WORDS: • biotin • human • monocarboxylate transporter • peripheral blood mononuclear cells • transport

This article has been cited by other articles:

				I. Peluso, D. Fina, R. Caruso, C. Stolfi, F. Caprioli, M. C. Fantini, G. Caspani, E. Grossi, L. Di Iorio, F. M. Paone, et al. Lactobacillus paracasei subsp. paracasei B21060 Suppresses Human T-Cell Proliferation Infect. Immun., April 1, 2007; 75(4): 1730 - 1737. [Abstract] [Full Text] [PDF]

				A. Alkemade, E. C Friesema, G. G Kuiper, W. M Wiersinga, D. F Swaab, T. J Visser, and E. Fliers Novel neuroanatomical pathways for thyroid hormone action in the human anterior pituitary. Eur. J. Endocrinol., March 1, 2006; 154(3): 491 - 500. [Abstract] [Full Text] [PDF]

				T. I. Vlasova, S. L. Stratton, A. M. Wells, N. I. Mock, and D. M. Mock Biotin Deficiency Reduces Expression of SLC19A3, a Potential Biotin Transporter, in Leukocytes from Human Blood J. Nutr., January 1, 2005; 135(1): 42 - 47. [Abstract] [Full Text] [PDF]