Profiles of antioxidant/electrophile response element (ARE/EpRE) nuclear protein binding and c-Ha-ras transactivation in vascular smooth muscle cells treated with oxidative metabolites of benzo[a]pyrene
Section snippets
Reagents
BaP (98% purity) was obtained from the Aldrich Chemical Co., and BaP 3,6-Q (≥98% purity by HPLC), 3-hydroxy BaP (≥99% purity by HPLC), and BaP 7,8-diol (≥98% purity by HPLC) were obtained from the National Cancer Institute Chemical Carcinogen Reference Standard Repositories (c/o Midwest Research Institute). All other chemicals were purchased from the Sigma Chemical Co. unless otherwise noted. BaP, 3-OH BaP, BaP 7,8-diol, and BaP 3,6-Q stock solutions were prepared in DMSO, and H2O2 stock
Activation of protein binding to c-Ha-ras ARE/EpRE by BaP metabolites
Previous work in this laboratory has shown that BaP induces specific protein binding to hHa-ras ARE/EpRE [8]. To assess the possible role of BaP metabolites in the activation of protein binding, the effects of 3-OH BaP, BaP 7,8-diol, and BaP 3,6-Q in vSMCs were examined. Cells were challenged for 3 hr with individual metabolites at concentrations comparable to or lower than those required to activate ARE/EpRE protein binding by the parent compound. The range of concentrations examined was based
Discussion
In this report we showed that oxidative intermediates of BaP activate protein binding to the ARE/EpRE and up-regulate transcription of reporter plasmids containing the ARE/EpRE sequence directly upstream of c-Ha-ras regulatory sequences. The threshold and concentration-dependent profiles of protein binding and transactivation in response to 3-OH BaP, BaP 7,8-diol, and BaP 3,6-Q suggest that oxidative intermediates participate in the deregulation of c-Ha-ras gene expression by BaP in vSMCs.
Acknowledgements
This work was supported, in part, by NIEHS Grants 04849 to K. S. R. and Center Grant ES 09106. K. P. M. is a predoctoral fellow on NIEHS Training Grant T32 ES 07273.
References (45)
- et al.
Growth-related signaling as a target of toxic insult in vascular tissue
Life Sci
(1995) - et al.
Further investigations of the capacity of polynuclear aromatic hydrocarbons to elicit atherosclerotic lesions
J Toxicol Environ Health
(1981) - et al.
An ultrastructural comparison of carcinogen-associated and spontaneous aortic lesions in the cockerel
Am J Pathol
(1984) - et al.
Proliferative responses of quail aortic smooth muscle cells to benzo[a]pyreneImplications in PAH-induced atherogenesis
Toxicology
(1992) - et al.
Benzo[a]pyrene enhances atherosclerosis in White Carneau and Show Racer pigeons
Arterioscler Thromb
(1993) - et al.
Interference with PKC-related mitogenic signal transduction in vascular smooth muscle cells
Arch Biochem Biophys
(1995) - et al.
Modulation of protooncogene expression in rat aortic smooth muscle cells by benzo[a]pyrene
Arch Biochem Biophys
(1993) - et al.
Identification of benzo[a]pyrene-inducible cis-acting elements within c-Ha-ras transcriptional regulatory sequences
Mol Pharmacol
(1997) - et al.
Metabolism of benzo[a]pyrene and 7,12-dimethylbenz[a]anthracene in chicken aortasMonooxygenation, bioactivation to mutagens, and covalent binding to DNA in vitro
Toxicol Appl Pharmacol
(1980) - et al.
Induction of cytochrome CYPIA1 and formation of toxic metabolites of benzo[a]pyrene by rat aortaA possible role in atherogenesis
Proc Natl Acad Sci USA
(1994)
Kinetics, activation, and induction of aortic mono-oxygenases—Biotransformation of benzo[a]pyrene
Biochem Pharmacol
Benzo[a]pyrene inhibits protein kinase C activity in subcultured rat aortic smooth muscle cells
Chem Biol Interact
Activation of c-Ha-ras by benzo[a]pyrene in vascular smooth muscle cells involves redox stress and aryl hydrocarbon receptor
Mol Pharmacol
Benzo[a]pyrene metabolism, activation and carcinogenesisRole and regulation of mixed-function oxidases and related enzymes
Physiol Rev
Benzo[a]pyrene dione–benzo[a]pyrene diol oxidation—reduction couples; Involvement in DNA damage, cellular toxicity, and carcinogenesis
J Toxicol Environ Health
Benzo[a]pyrenedione/benzo[a]pyrenediol oxidation-reduction couples and the generation of reactive reduced molecular oxygen
Biochemistry
Metabolic conversion of benzo[a]pyrene by Syrian hamster liver microsomes and binding of metabolites to deoxyribonucleic acid
J Med Chem
High-pressure liquid chromatographic analysis of benzo(a)pyrene metabolism and covalent binding and the mechanism of action of 7,8-benzoflavone and 1,2-epoxy-3,3,3-trichloropropane
Cancer Res
The rat liver glutathione S-transferase Ya subunit geneCharacterization of the binding properties of a nuclear protein from HepG2 cells that has high affinity for the antioxidant response element
Biochemistry
Oxy radicals and antioxidative responses in cancer12th Sapporo Cancer Seminar
Cancer Res
The antioxidant responsive element
J Biol Chem
Transcriptional regulation of a rat liver glutathione S-transferase Ya subunit gene
J Biol Chem
Cited by (20)
Flavonoids as detoxifying and pro-survival agents: What's new?
2017, Food and Chemical ToxicologyCitation Excerpt :This evidence should encourage the study of plant-derived flavonoids as detoxifying agents. The polyphenols could activate detoxification enzyme through the antioxidant/electrophile response element (ARE/EpRE) in the promoter domain (Mullinck and van Blomberg, 1980; Miller et al., 2000; Day and Williamson, 2001; Slama et al., 2017). Interestingly, the effects that flavonoids, in general, have on enzymes depend on the levels the latter have inside the cell, their tissue distribution, and flavonoids bioactivity and bioavailability, besides their chemistry.
Benzo[a]pyrene affects Jurkat T cells in the activated state via the antioxidant response element dependent Nrf2 pathway leading to decreased IL-2 secretion and redirecting glutamine metabolism
2013, Toxicology and Applied PharmacologyCitation Excerpt :Due to oxidation KEAP loses its ability to sequester Nrf2 in the cytosol. The dissociated Nrf2 then translocates into the nucleus, where it binds and activates the antioxidant/electrophile response element (ARE/EpRE), which is responsible for the transcription of second phase detoxification enzymes (Burczynski and Penning, 2000; Miller et al., 2000), and other proteins (Garg et al., 2008; Tkachev et al., 2011). In particular, ARE regulates proteins involved in hydrolysis (carbonyl esterase), reduction (carbonyl reductase), oxidation (aldehyde dehydrogenase), glucuronidation pathway (UDP-glucose dehydrogenase) and glutathione synthesis (GCS, regulatory subunit) as well as glutathione transferases (GST class mu), antioxidants (glutathione peroxidase), protective proteins (multidrug resistance protein), NADPH regenerating enzymes (G6PDH), inflammatory suppressive genes (glucocorticoid-regulated kinase) and others that cannot be summed up in a common group like tryptophan hydrolase (Thimmulappa et al., 2002).
Genetic and molecular mechanisms of chemical atherogenesis
2007, Mutation Research - Fundamental and Molecular Mechanisms of MutagenesisDietary chemopreventive compounds and ARE/EpRE signaling
2004, Free Radical Biology and MedicineRedox regulation of a novel L1Md-A2 retrotransposon in vascular smooth muscle cells
2003, Journal of Biological ChemistryCitation Excerpt :ARE-binding proteins are redox-regulated transcription factors of the basic leucine zipper superfamily that “sense” alterations in cellular redox balance following environmental stress (44). Over production of free radicals via cycles of reduction and oxidation between phenolic and quinone intermediates in BaP-treated cells induces oxidative stress and activates ARE signaling in vascular smooth muscle cells (51). As shown for other BaP-responsive genes, AREs mediate transcriptional regulation of L1Md-A3.6.
- ∗
Present address: Schering Plough Research Institute, Lafayette, NJ 07848.