title: Potency of isothiocyanates to induce luciferase reporter gene expression via the electrophile-responsive element from murine glutathione S-transferase Ya.
abstract: Isothiocyanates are electrophiles that are able to induce phase II biotransformation enzyme gene expression via an electrophile-responsive element (EpRE) in the gene regulatory region. To study the potency of different isothiocyanates to induce the expression of EpRE-regulated genes, a Hepa-1c1c7 luciferase reporter cell line was exposed to structurally different isothiocyanates. The reporter cell line, EpRE(mGST-Ya)-LUX, contains the EpRE from the regulatory region of the mouse glutathione S-transferase Ya gene. Isothiocyanates containing a methyl-sulfur side chain, e.g. sulforaphane, showed a lower EC(50) (0.8-3.2 microM) and a comparable induction factor (17-22.4) compared to the structurally different isothiocyanates containing an alkyl or aromatic side chain, e.g. allyl and phenylethyl isothiocyanate (EC(50) 3.9-6.5 microM, induction factor 17.5-23). After 24h of exposure, on average (+/-SD) 23+/-5% of the isothiocyanate was found in the cells and 77% in the cell medium. Isothiocyanates prove to be strong inducers of electrophile-responsive element-mediated gene expression at physiological concentrations. The here described luciferase reporter cell line is a suitable assay to measure the potency of compounds to induce EpRE-regulated gene expression.
authors.affiliation: Nutrients and Biomarkers Department, TNO Quality of Life, 3700 AJ Zeist, The Netherlands. Martijn.Vermeulen@tno.nl
authors.forename: Martijn
authors.initials: M
authors.lastname: Vermeulen
authors.forename: Anne-Marie M J F
authors.initials: AM
authors.lastname: Boerboom
authors.forename: Barry M G
authors.initials: BM
authors.lastname: Blankvoort
authors.forename: Jac M M J G
authors.initials: JM
authors.lastname: Aarts
authors.forename: Ivonne M C M
authors.initials: IM
authors.lastname: Rietjens
authors.forename: Peter J
authors.initials: PJ
authors.lastname: van Bladeren
authors.forename: Wouter H J
authors.initials: WH
authors.lastname: Vaes
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects*; D017930:Genes, Reporter; D005982:Glutathione Transferase / Q000235:genetics*; D017879:Isothiocyanates / Q000494:pharmacology*; D008156:Luciferases / Q000235:genetics*; D051379:Mice; D020218:Response Elements / Q000502:physiology*
chemical_list: D017879:Isothiocyanates; D008156:Luciferases; D005982:Glutathione Transferase