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

This Article Full Text Full Text (PDF) All Versions of this Article: dmd.107.018036v1 36/2/276    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted 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 Meinl, W. Articles by Lampen, A. Search for Related Content PubMed PubMed Citation Articles by Meinl, W. Articles by Lampen, A.

Sulfotransferase Forms Expressed in Human Intestinal Caco-2 and TC7 Cells at Varying Stages of Differentiation and Role in Benzo[a]pyrene Metabolism

Department of Nutritional Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, Nuthetal, Germany (W.M., H.G.); Department of Food Toxicology, School of Veterinary Medicine, Hannover, Germany (B.E.); and Department of Food Safety, Federal Institute for Risk Assessment, Berlin, Germany (A.L.)

The Caco-2 cell line and its subclone TC7 are frequently used for studying human intestinal transport and metabolism of xenobiotics. We have investigated the expression of soluble sulfotransferases (SULT) in parental Caco-2 and TC7 cells by immunoblotting. SULT1A1, SULT1A2, SULT1A3, SULT1B1, SULT1C1, SULT1C2, and SULT2A1 were expressed in both cell lines. SULT2B1a, SULT2B1b, and SULT4A1 were absent. SULT1E1 protein was found in TC7 but not in Caco-2 cells. Other differences in SULT between the cell lines were minor. More important was the influence of differentiation. Expression of the various SULT forms was low or not detectable in cultures just reaching confluence but then increased strongly. Likewise, the rate of sulfation of the model substrate 3-hydroxybenzo[a]pyrene was increased with increasing culture duration. Benzo[a]pyrene-1-sulfate and -3-sulfate were formed in both cell lines when benzo[a]pyrene was used as a substrate. A further metabolite, 3-hydroxybenzo[a]pyrene-glucuronide, was detected in TC7 but not in parental Caco-2 cells. Cytochrome P450 inducers enhanced the conversion of benzo[a]pyrene to these metabolites without altering mRNA levels of major phenol-conjugating SULT forms (SULT1A1, SULT1A3, and SULT1B1). Overall, differentiated Caco-2 and TC7 cells are rich sources of SULT, as is human intestinal mucosa. The SULT pattern is most similar to that found in small intestine, although levels of SULT1A1 and SULT1B1 are lower, and those of SULT1C1 are higher in Caco-2 and TC7 cells than previously found in intestinal samples. The differentiation-dependent expression of SULT in the cultured cells reflects the in vivo situation, where SULT expression is focused to differentiated enterocytes.

This article has been cited by other articles:

				S. Siissalo, H. Zhang, E. Stilgenbauer, A. M. Kaukonen, J. Hirvonen, and M. Finel The Expression of Most UDP-Glucuronosyltransferases (UGTs) Is Increased Significantly during Caco-2 Cell Differentiation, whereas UGT1A6 Is Highly Expressed Also in Undifferentiated Cells Drug Metab. Dispos., November 1, 2008; 36(11): 2331 - 2336. [Abstract] [Full Text] [PDF]