Abstract
The secretion of a glutathione-S-conjugate, dinitrophenyl-glutathione (GS-DNP) was studied in the Caco-2 cells, a cultured human colonic adenocarcinoma cell line with many of the characteristics of enterocytes. The labelled glutathione conjugate was generated within the cell by incubation with 14C-labelled 1-chloro-2,4-dinitrobenzene (CDNB). This compound is hydrophobic and enters the cell by simple diffusion. Cells incubated with CDNB at 10 degrees C form only one metabolite, GS-DNP. After secretion into the medium GS-DNP is partly converted into one or two slightly more hydrophobic products. This must represent hydrolysis of the glutathione moiety by the action of gamma-glutamyltransferase (EC 2.3.2.2.; gamma-GT) because the reaction was completely inhibited by acivicin, an inhibitor of gamma-GT. Secretion of GS-DNP was a temperature-sensitive, saturable process with an apparent Km of 1.03 +/- 0.26 nmol/mg of protein and a Vmax of 111 +/- 17 pmol/min per mg of protein. The secretion was not sensitive to trans-stimulation by extracellular concentrations of GS-DNP up to 2.5 mM. Furthermore the initial GS-DNP secretion rate was sensitive to dissipation of the membrane potential and correlated closely with the cellular ATP content. Caco-2 cells cultured on nitrocellulose filters secreted GS-DNP significantly faster over the basolateral membrane than over the apical membrane (146 +/- 25 versus 90 +/- 18 pmol/min per mg respectively). Secretion over both membrane domains of the cell was sensitive to ATP depletion. In conclusion, Caco-2 cells contain an active-transport system that is primarily involved in the secretion of glutathione conjugates and that is present in both plasma membrane domains of the cell.
Full text
PDF





Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Akerboom T. P., Narayanaswami V., Kunst M., Sies H. ATP-dependent S-(2,4-dinitrophenyl)glutathione transport in canalicular plasma membrane vesicles from rat liver. J Biol Chem. 1991 Jul 15;266(20):13147–13152. [PubMed] [Google Scholar]
- Elferink R. P., Ottenhoff R., Liefting W., de Haan J., Jansen P. L. Hepatobiliary transport of glutathione and glutathione conjugate in rats with hereditary hyperbilirubinemia. J Clin Invest. 1989 Aug;84(2):476–483. doi: 10.1172/JCI114189. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Exton J. H. Signaling through phosphatidylcholine breakdown. J Biol Chem. 1990 Jan 5;265(1):1–4. [PubMed] [Google Scholar]
- Hartiala K. Metabolism of hormones, drugs and other substances by the gut. Physiol Rev. 1973 Apr;53(2):496–534. doi: 10.1152/physrev.1973.53.2.496. [DOI] [PubMed] [Google Scholar]
- Hidalgo I. J., Borchardt R. T. Transport of a large neutral amino acid (phenylalanine) in a human intestinal epithelial cell line: Caco-2. Biochim Biophys Acta. 1990 Sep 21;1028(1):25–30. doi: 10.1016/0005-2736(90)90261-l. [DOI] [PubMed] [Google Scholar]
- Hidalgo I. J., Raub T. J., Borchardt R. T. Characterization of the human colon carcinoma cell line (Caco-2) as a model system for intestinal epithelial permeability. Gastroenterology. 1989 Mar;96(3):736–749. [PubMed] [Google Scholar]
- Inui K., Yamamoto M., Saito H. Transepithelial transport of oral cephalosporins by monolayers of intestinal epithelial cell line Caco-2: specific transport systems in apical and basolateral membranes. J Pharmacol Exp Ther. 1992 Apr;261(1):195–201. [PubMed] [Google Scholar]
- Ishikawa T. ATP/Mg2+-dependent cardiac transport system for glutathione S-conjugates. A study using rat heart sarcolemma vesicles. J Biol Chem. 1989 Oct 15;264(29):17343–17348. [PubMed] [Google Scholar]
- Jansen P. L., Oude Elferink R. P. Hereditary hyperbilirubinemias: a molecular and mechanistic approach. Semin Liver Dis. 1988 May;8(2):168–178. doi: 10.1055/s-2008-1040537. [DOI] [PubMed] [Google Scholar]
- Kitamura T., Jansen P., Hardenbrook C., Kamimoto Y., Gatmaitan Z., Arias I. M. Defective ATP-dependent bile canalicular transport of organic anions in mutant (TR-) rats with conjugated hyperbilirubinemia. Proc Natl Acad Sci U S A. 1990 May;87(9):3557–3561. doi: 10.1073/pnas.87.9.3557. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LaBelle E. F., Singh S. V., Srivastava S. K., Awasthi Y. C. Dinitrophenyl glutathione efflux from human erythrocytes is primary active ATP-dependent transport. Biochem J. 1986 Sep 1;238(2):443–449. doi: 10.1042/bj2380443. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Leibovitz A., Stinson J. C., McCombs W. B., 3rd, McCoy C. E., Mazur K. C., Mabry N. D. Classification of human colorectal adenocarcinoma cell lines. Cancer Res. 1976 Dec;36(12):4562–4569. [PubMed] [Google Scholar]
- Lindwall G., Boyer T. D. Excretion of glutathione conjugates by primary cultured rat hepatocytes. J Biol Chem. 1987 Apr 15;262(11):5151–5158. [PubMed] [Google Scholar]
- Mohrmann I., Mohrmann M., Biber J., Murer H. Sodium-dependent transport of Pi by an established intestinal epithelial cell line (CaCo-2). Am J Physiol. 1986 Mar;250(3 Pt 1):G323–G330. doi: 10.1152/ajpgi.1986.250.3.G323. [DOI] [PubMed] [Google Scholar]
- Oude Elferink R. P., Ottenhoff R., Liefting W. G., Schoemaker B., Groen A. K., Jansen P. L. ATP-dependent efflux of GSSG and GS-conjugate from isolated rat hepatocytes. Am J Physiol. 1990 May;258(5 Pt 1):G699–G706. doi: 10.1152/ajpgi.1990.258.5.G699. [DOI] [PubMed] [Google Scholar]
- Pekas J. C. Naphthol metabolism: glucuronide conjugation and transport by the rat intestine in vitro. Toxicol Appl Pharmacol. 1974 Sep;29(3):404–419. doi: 10.1016/0041-008x(74)90113-6. [DOI] [PubMed] [Google Scholar]
- Peters W. H., Roelofs H. M., Nagengast F. M., van Tongeren J. H. Human intestinal glutathione S-transferases. Biochem J. 1989 Jan 15;257(2):471–476. doi: 10.1042/bj2570471. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peters W. H., Roelofs H. M. Time-dependent activity and expression of glutathione S-transferases in the human colon adenocarcinoma cell line Caco-2. Biochem J. 1989 Dec 1;264(2):613–616. doi: 10.1042/bj2640613. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schwenk M., Schiemenz C., del Pino V. L., Remmer H. First pass biotransformation of ethinylestradiol in rat small intestine in situ. Naunyn Schmiedebergs Arch Pharmacol. 1982 Dec;321(3):223–225. doi: 10.1007/BF00505490. [DOI] [PubMed] [Google Scholar]
- Wahlländer A., Sies H. Glutathione S-conjugate formation from 1-chloro-2,4-dinitrobenzene and biliary S-conjugate excretion in the perfused rat liver. Eur J Biochem. 1979 Jun 1;96(3):441–446. doi: 10.1111/j.1432-1033.1979.tb13056.x. [DOI] [PubMed] [Google Scholar]
- Wollenberg P., Rummel W. Vectorial release of sulfoconjugates in the vascularly perfused mouse small intestine. Biochem Pharmacol. 1984 Jan 15;33(2):205–208. doi: 10.1016/0006-2952(84)90477-5. [DOI] [PubMed] [Google Scholar]
- de Vries M. H., Hofman G. A., Koster A. S., Noordhoek J. Absorption and presystemic glucuronidation of 1-naphthol in the vascularly fluorocarbon emulsion perfused rat small intestine. The influence of 1-naphthol concentration, perfusate flow and noradrenaline. Naunyn Schmiedebergs Arch Pharmacol. 1989 Aug;340(2):239–245. doi: 10.1007/BF00168975. [DOI] [PubMed] [Google Scholar]
- de Vries M. H., Redegeld F. A., Koster A. S., Noordhoek J., de Haan J. G., Oude Elferink R. P., Jansen P. L. Hepatic, intestinal and renal transport of 1-naphthol-beta-D-glucuronide in mutant rats with hereditary-conjugated hyperbilirubinemia. Naunyn Schmiedebergs Arch Pharmacol. 1989 Nov;340(5):588–592. doi: 10.1007/BF00260615. [DOI] [PubMed] [Google Scholar]
