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Roshani M, Jafari A, Loghman A, Sheida AH, Taghavi T, Tamehri Zadeh SS, Hamblin MR, Homayounfal M, Mirzaei H. Applications of resveratrol in the treatment of gastrointestinal cancer. Biomed Pharmacother 2022; 153:113274. [PMID: 35724505 DOI: 10.1016/j.biopha.2022.113274] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/28/2022] [Accepted: 06/08/2022] [Indexed: 12/15/2022] Open
Abstract
Natural product compounds have lately attracted interest in the scientific community as a possible treatment for gastrointestinal (GI) cancer, due to their anti-inflammatory and anticancer properties. There are many preclinical, clinical, and epidemiological studies, suggesting that the consumption of polyphenol compounds, which are abundant in vegetables, grains, fruits, and pulses, may help to prevent various illnesses and disorders from developing, including several GI cancers. The development of GI malignancies follows a well-known path, in which normal gastrointestinal cells acquire abnormalities in their genetic composition, causing the cells to continuously proliferate, and metastasize to other sites, especially the brain and liver. Natural compounds with the ability to affect oncogenic pathways might be possible treatments for GI malignancies, and could easily be tested in clinical trials. Resveratrol is a non-flavonoid polyphenol and a natural stilbene, acting as a phytoestrogen with anti-cancer, cardioprotective, anti-oxidant, and anti-inflammatory properties. Resveratrol has been shown to overcome resistance mechanisms in cancer cells, and when combined with conventional anticancer drugs, could sensitize cancer cells to chemotherapy. Several new resveratrol analogs and nanostructured delivery vehicles with improved anti-GI cancer efficacy, absorption, and pharmacokinetic profiles have already been developed. This present review focuses on the in vitro and in vivo effects of resveratrol on GI cancers, as well as the underlying molecular mechanisms of action.
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Affiliation(s)
- Mohammad Roshani
- Internal Medicine and Gastroenterology, Colorectal Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Ameneh Jafari
- Advanced Therapy Medicinal Product (ATMP) Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran; Proteomics Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Amir Hossein Sheida
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran; Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | | | | | - Michael R Hamblin
- Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein 2028, South Africa
| | - Mina Homayounfal
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran
| | - Hamed Mirzaei
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran.
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Zapletal O, Procházková J, Dubec V, Hofmanová J, Kozubík A, Vondráček J. Butyrate interacts with benzo[a]pyrene to alter expression and activities of xenobiotic metabolizing enzymes involved in metabolism of carcinogens within colon epithelial cell models. Toxicology 2018; 412:1-11. [PMID: 30439556 DOI: 10.1016/j.tox.2018.11.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 10/30/2018] [Accepted: 11/08/2018] [Indexed: 01/24/2023]
Abstract
Butyrate helps to maintain colon homeostasis and exhibits chemopreventive effects in colon epithelium. We examined the interactive effects of butyrate and benzo[a]pyrene (BaP), dietary carcinogen, in regulation of expression of a panel of phase I and II xenobiotic metabolizing enzymes (XMEs) in human colon cells. In human colon carcinoma HCT-116 and HT-29 cell lines, butyrate alone increased mRNA levels of some enzymes, such as N-acetyltransferases (in particular NAT2). In combination with BaP, butyrate potentiated induction of cytochrome P450 family 1 enzymes (CYP1A1), aldo-keto reductases (AKR1C1) or UDP-glucuronosyltransferases (UGT1A1). There were some notable differences between cell lines, as butyrate potentiated induction of NAD(P)H:quinone oxidoreductase 1 (NQO1) and UGT1A4 only in HCT-116 cells, and it even repressed AKR1C3 induction in HT-29 cells. Butyrate also promoted induction of CYP1, NQO1, NAT2, UGT1A1 or UGT1A4 in human colon Caco-2 cells, in a differentiation-dependent manner. Differentiated Caco-2 cells exhibited a higher inducibility of selected XME genes than undifferentiated cells. Butyrate increased induction of enzymatic activities of NATs, NQO1 and UGTs by BaP in HCT-116 and HT29 cells, whereas in differentiated Caco-2 cells it helped to increase only enzymatic activity of NQO1 and UGTs. Together, the present data suggest that butyrate may modulate expression/activities of several enzymes involved in metabolism of carcinogens in colon. In some cases (NAT2, UGT1 A1), this was linked to inhibition of histone deacetylases (HDAC), as confirmed by using HDAC inhibitor trichostatin A. These results may have implications for our understanding of the role of butyrate in regulation of XMEs and carcinogen metabolism in colon.
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Affiliation(s)
- Ondřej Zapletal
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, 61265 Brno, Czech Republic; Department of Experimental Biology, Faculty of Science, Masaryk University, 61137 Brno, Czech Republic
| | - Jiřina Procházková
- Department of Chemistry and Toxicology, Veterinary Research Institute, 62100 Brno, Czech Republic
| | - Vít Dubec
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, 61265 Brno, Czech Republic; Department of Experimental Biology, Faculty of Science, Masaryk University, 61137 Brno, Czech Republic
| | - Jiřina Hofmanová
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, 61265 Brno, Czech Republic
| | - Alois Kozubík
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, 61265 Brno, Czech Republic
| | - Jan Vondráček
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, 61265 Brno, Czech Republic.
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Rendic SP, Guengerich FP. Development and Uses of Offline and Web-Searchable Metabolism Databases - The Case of Benzo[a]pyrene. Curr Drug Metab 2018; 19:3-46. [PMID: 29219051 DOI: 10.2174/1389200219666171207123939] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 11/04/2017] [Accepted: 11/11/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND The present work describes development of offline and web-searchable metabolism databases for drugs, other chemicals, and physiological compounds using human and model species, prompted by the large amount of data published after year 1990. The intent was to provide a rapid and accurate approach to published data to be applied both in science and to assist therapy. METHODS Searches for the data were done using the Pub Med database, accessing the Medline database of references and abstracts. In addition, data presented at scientific conferences (e.g., ISSX conferences) are included covering the publishing period beginning with the year 1976. RESULTS Application of the data is illustrated by the properties of benzo[a]pyrene (B[a]P) and its metabolites. Analysis show higher activity of P450 1A1 for activation of the (-)- isomer of trans-B[a]P-7,8-diol, while P4501B1 exerts higher activity for the (+)- isomer. P450 1A2 showed equally low activity in the metabolic activation of both isomers. CONCLUSION The information collected in the databases is applicable in prediction of metabolic drug-drug and/or drug-chemical interactions in clinical and environmental studies. The data on the metabolism of searched compound (exemplified by benzo[a]pyrene and its metabolites) also indicate toxicological properties of the products of specific reactions. The offline and web-searchable databases had wide range of applications (e.g. computer assisted drug design and development, optimization of clinical therapy, toxicological applications) and adjustment in everyday life styles.
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Affiliation(s)
| | - Frederick P Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
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Butyrate alters expression of cytochrome P450 1A1 and metabolism of benzo[a]pyrene via its histone deacetylase activity in colon epithelial cell models. Arch Toxicol 2016; 91:2135-2150. [PMID: 27830268 DOI: 10.1007/s00204-016-1887-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 11/02/2016] [Indexed: 01/24/2023]
Abstract
Butyrate, a short-chain fatty acid produced by fermentation of dietary fiber, is an important regulator of colonic epithelium homeostasis. In this study, we investigated the impact of this histone deacetylase (HDAC) inhibitor on expression/activity of cytochrome P450 family 1 (CYP1) and on metabolism of carcinogenic polycyclic aromatic hydrocarbon, benzo[a]pyrene (BaP), in colon epithelial cells. Sodium butyrate (NaBt) strongly potentiated the BaP-induced expression of CYP1A1 in human colon carcinoma HCT116 cells. It also co-stimulated the 7-ethoxyresorufin-O-deethylase (EROD) activity induced by the 2,3,7,8-tetrachlorodibenzo-p-dioxin, a prototypical ligand of the aryl hydrocarbon receptor. Up-regulation of CYP1A1 expression/activity corresponded with an enhanced metabolism of BaP and formation of covalent DNA adducts. NaBt significantly potentiated CYP1A1 induction and/or metabolic activation of BaP also in other human colon cell models, colon adenoma AA/C1 cells, colon carcinoma HT-29 cells, or in NCM460D cell line derived from normal colon mucosa. Our results suggest that the effects of NaBt were due to its impact on histone acetylation, because additional HDAC inhibitors (trichostatin A and suberanilohydroxamic acid) likewise increased both the induction of EROD activity and formation of covalent DNA adducts. NaBt-induced acetylation of histone H3 (at Lys14) and histone H4 (at Lys16), two histone modifications modulated during activation of CYP1A1 transcription, and it reduced binding of HDAC1 to the enhancer region of CYP1A1 gene. This in vitro study suggests that butyrate, through modulation of histone acetylation, may potentiate induction of CYP1A1 expression, which might in turn alter the metabolism of BaP within colon epithelial cells.
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Nrf2 activators as potential modulators of injury in human kidney cells. Toxicol Rep 2016; 3:153-159. [PMID: 28959534 PMCID: PMC5615789 DOI: 10.1016/j.toxrep.2016.01.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 01/07/2016] [Accepted: 01/07/2016] [Indexed: 12/14/2022] Open
Abstract
Cisplatin is a chemotherapeutic agent used in the treatment of solid tumors, with clinical use often complicated by kidney toxicity. Nuclear factor (erythroid-derived-2)-like 2 (Nrf2) is a transcription factor involved in kidney protectant effects. The purpose of this study was to determine whether the Nrf2 activators oltipraz, sulforaphane, and oleanolic acid could protect human kidney cells against cisplatin-induced injury and to compare the protective effects between three Nrf2 activators. Human proximal tubule cells (hPTC) and human embryonic kidney 293 cells (HEK293) were exposed to cisplatin doses in the absence and presence of Nrf2 activators. Pre- and delayed-cisplatin and Nrf2 activator exposures were also assessed. Cell viability was enhanced with Nrf2 activator exposures, with differences detected between pre- and delayed-treatments. Both sulforaphane and oltipraz increased the expression of anti-oxidant genes GCLC and NQO1. These findings suggest potential human kidney protective benefits of Nrf2 activators with planned exposures to cisplatin.
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Xie G, Raufman JP. Role of the Aryl Hydrocarbon Receptor in Colon Neoplasia. Cancers (Basel) 2015; 7:1436-46. [PMID: 26264025 PMCID: PMC4586780 DOI: 10.3390/cancers7030847] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 07/27/2015] [Accepted: 07/29/2015] [Indexed: 12/27/2022] Open
Abstract
For both men and women, colorectal cancer (CRC) is the second leading cause of cancer death in the United States, primarily as a consequence of limited therapies for metastatic disease. The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor with diverse functions in detoxification of xenobiotics, inflammatory responses, and tissue homeostasis. Emerging evidence indicates that AhR also plays an important role in regulating intestinal cell proliferation and tumorigenesis. Here, we review both the pro- and anti-carcinogenic properties of AhR signaling and its potential role as a therapeutic target in CRC.
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Affiliation(s)
- Guofeng Xie
- Division of Gastroenterology and Hepatology, Veterans Administration Maryland Health Care System, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
| | - Jean-Pierre Raufman
- Division of Gastroenterology and Hepatology, Veterans Administration Maryland Health Care System, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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Verma N, Pink M, Petrat F, Rettenmeier AW, Schmitz-Spanke S. Proteomic Analysis of Human Bladder Epithelial Cells by 2D Blue Native SDS-PAGE Reveals TCDD-Induced Alterations of Calcium and Iron Homeostasis Possibly Mediated by Nitric Oxide. J Proteome Res 2014; 14:202-13. [DOI: 10.1021/pr501051f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Nisha Verma
- Gene
Center, Ludwig-Maximilians-University, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Mario Pink
- Institute
and Outpatient Clinic of Occupational, Social and Environmental Medicine, University of Erlangen-Nuremberg, Schillerstr. 25/29, 91054 Erlangen, Germany
| | | | | | - Simone Schmitz-Spanke
- Institute
and Outpatient Clinic of Occupational, Social and Environmental Medicine, University of Erlangen-Nuremberg, Schillerstr. 25/29, 91054 Erlangen, Germany
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McCalley AE, Kaja S, Payne AJ, Koulen P. Resveratrol and calcium signaling: molecular mechanisms and clinical relevance. Molecules 2014; 19:7327-40. [PMID: 24905603 PMCID: PMC4160047 DOI: 10.3390/molecules19067327] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 05/23/2014] [Accepted: 05/23/2014] [Indexed: 11/16/2022] Open
Abstract
Resveratrol is a naturally occurring compound contributing to cellular defense mechanisms in plants. Its use as a nutritional component and/or supplement in a number of diseases, disorders, and syndromes such as chronic diseases of the central nervous system, cancer, inflammatory diseases, diabetes, and cardiovascular diseases has prompted great interest in the underlying molecular mechanisms of action. The present review focuses on resveratrol, specifically its isomer trans-resveratrol, and its effects on intracellular calcium signaling mechanisms. As resveratrol's mechanisms of action are likely pleiotropic, its effects and interactions with key signaling proteins controlling cellular calcium homeostasis are reviewed and discussed. The clinical relevance of resveratrol's actions on excitable cells, transformed or cancer cells, immune cells and retinal pigment epithelial cells are contrasted with a review of the molecular mechanisms affecting calcium signaling proteins on the plasma membrane, cytoplasm, endoplasmic reticulum, and mitochondria. The present review emphasizes the correlation between molecular mechanisms of action that have recently been identified for resveratrol and their clinical implications.
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Affiliation(s)
- Audrey E McCalley
- Vision Research Center, Department of Ophthalmology, School of Medicine, University of Missouri-Kansas City, 2411 Holmes St., Kansas City, MO 64108, USA.
| | - Simon Kaja
- Vision Research Center, Department of Ophthalmology, School of Medicine, University of Missouri-Kansas City, 2411 Holmes St., Kansas City, MO 64108, USA.
| | - Andrew J Payne
- Vision Research Center, Department of Ophthalmology, School of Medicine, University of Missouri-Kansas City, 2411 Holmes St., Kansas City, MO 64108, USA.
| | - Peter Koulen
- Vision Research Center, Department of Ophthalmology, School of Medicine, University of Missouri-Kansas City, 2411 Holmes St., Kansas City, MO 64108, USA.
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Calcium signaling and β2-adrenergic receptors regulate 1-nitropyrene induced CXCL8 responses in BEAS-2B cells. Toxicol In Vitro 2014; 28:1153-7. [PMID: 24904980 DOI: 10.1016/j.tiv.2014.05.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 04/25/2014] [Accepted: 05/26/2014] [Indexed: 02/06/2023]
Abstract
Nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) are widespread environmental pollutants, generated from reactions between PAHs and nitrogen oxides during combustion processes. In the present study we have investigated the mechanisms of CXCL8 (IL-8) responses induced by 1-nitropyrene (1-NP) in human bronchial epithelial BEAS-2B cells, with focus on the possible importance of Ca(2+)-signaling and activation of β2-adrenergic receptors (β2AR). Ca(2+)-chelator treatment obliterated 1-NP-induced CXCL8 (IL-8) responses. 1-NP at 10μM (but not 1μM) induced a rapid and sustained increase in intracellular Ca(2+)-levels ([Ca(2+)]i). The early but not the later, sustained phase of 1-NP-induced [Ca(2+)]i was suppressed by beta-blocker treatment (carazolol). Moreover, inhibition of β2AR by blocking-antibody, beta-blocker treatment (ICI 118551) or siRNA transfection attenuated CXCL8 responses induced by 1-NP. The results confirm that PAHs may induce Ca(2+)-signaling also in BEAS-2B cells, at least partly through activation of β2AR, and suggest that both β2AR- and Ca(2+)-signaling may be involved in 1-NP-induced CXCL8 responses in bronchial epithelial cells.
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Yun JH, Lee SB, Kang K, Lee EH, Lee HJ, Jung SH, Nho CW. Bifunctional chemopreventive effects of Adenocaulon himalaicum through induction of detoxification enzymes and apoptosis. J Med Food 2014; 16:701-10. [PMID: 23957354 DOI: 10.1089/jmf.2012.2625] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Phase II detoxification enzymes are known to play essential roles in the detoxification and elimination of activated carcinogens during tumor initiation, while apoptosis is one of the most important chemopreventive targets for inhibiting tumor promotion in cancer. In this study, we investigated the cancer chemopreventive activity of two plant extracts, the ethanolic extract of Adenocaulon himalaicum (AHE) and the butanolic fraction of AHE (AHB). Both, the AHE and AHB induced NQO1 activity and had relatively high chemoprevention indices (CI=12.4). The AHE and AHB were associated with increased NQO1 and HO-1 mRNA levels via Nrf2-ARE pathway activation. In addition, the AHB increased CYP1A1 activity through AhR-XRE pathway activation. We also found that the AHE and AHB induced apoptosis, as evidenced by phosphatidylserine externalization, an increase in the sub-G0/G1 content, chromatin condensation, poly(ADP-ribose) polymerase cleavage, and p53 induction. These data suggest that AHE and AHB act as bifunctional inducers and that their chemopreventive effects result from the biphasic induction of phase II detoxification enzymes and apoptosis. Therefore, these results suggest that A. himalaicum plant extracts have potential for use as chemopreventive agents for the prevention and/or treatment of human cancers.
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Affiliation(s)
- Ji Ho Yun
- Functional Food Center, Korea Institute of Science and Technology, Gangneung, Korea
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Deng R, Xu C, Chen X, Chen P, Wang Y, Zhou X, Jin J, Niu L, Ying M, Huang M, Bi H. Resveratrol Suppresses the Inducible Expression of CYP3A4 Through the Pregnane X Receptor. J Pharmacol Sci 2014; 126:146-54. [DOI: 10.1254/jphs.14132fp] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Weerachayaphorn J, Luo Y, Mennone A, Soroka CJ, Harry K, Boyer JL. Deleterious effect of oltipraz on extrahepatic cholestasis in bile duct-ligated mice. J Hepatol 2014; 60:160-6. [PMID: 23978715 PMCID: PMC4054607 DOI: 10.1016/j.jhep.2013.08.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/18/2013] [Accepted: 08/08/2013] [Indexed: 12/30/2022]
Abstract
BACKGROUND & AIMS Oltipraz (4-methyl-5(pyrazinyl-2)-1-2-dithiole-3-thione), a promising cancer preventive agent, has an antioxidative activity and ability to enhance glutathione biosynthesis, phase II detoxification enzymes and multidrug resistance-associated protein-mediated efflux transporters. Oltipraz can protect against hepatotoxicity caused by carbon tetrachloride, acetaminophen and alpha-naphthylisothiocyanate. Whether oltipraz has hepato-protective effects on obstructive cholestasis is unknown. METHODS We administered oltipraz to mice for 5 days prior to bile duct ligation (BDL) for 3 days. Liver histology, liver function markers, bile flow rates and hepatic expression of profibrogenic genes were evaluated. RESULTS Mice pretreated with oltipraz prior to BDL demonstrated higher levels of serum aminotransferases and more severe liver damage than in control mice. Higher bile flow and glutathione secretion rates were observed in unoperated mice treated with oltipraz than in control mice, suggesting that liver necrosis in oltipraz-treated BDL mice may be related partially to increased bile-acid independent flow and biliary pressure. Oltipraz treatment in BDL mice enhanced α-smooth muscle actin expression, consistent with activation of hepatic stellate cells and portal fibroblasts. Matrix metalloproteinases (Mmp) 9 and 13 and tissue inhibitors of metalloproteinases (Timp) 1 and 2 levels were increased in the oltipraz-treated BDL group, suggesting that the secondary phase of liver injury induced by oltipraz might be due to excessive Mmp and Timp secretions, which induce remodeling of the extracellular matrix. CONCLUSIONS Oltipraz treatment exacerbates the severity of liver injury following BDL and should be avoided as therapy for extrahepatic cholestatic disorders due to bile duct obstruction.
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Affiliation(s)
- Jittima Weerachayaphorn
- Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA,Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Yuhuan Luo
- Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA
| | - Albert Mennone
- Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA
| | - Carol J. Soroka
- Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA
| | - Kathy Harry
- Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA
| | - James L. Boyer
- Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA,The corresponding author: James L. Boyer, M.D., Emeritus Director, Liver Center, Yale University School of Medicine, 333 Cedar Street, 1080 LMP, New Haven, CT 06520. Phone: (203) 785-5279; Fax: (203) 785-7273;
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Dephosphorylation of Sp1 at Ser-59 by protein phosphatase 2A (PP2A) is required for induction of CYP1A1 transcription after treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin or omeprazole. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2013; 1839:107-15. [PMID: 24382322 DOI: 10.1016/j.bbagrm.2013.12.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 12/01/2013] [Accepted: 12/23/2013] [Indexed: 11/23/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is a transcription factor that is activated by either 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or omeprazole (OP). Activated AhR can induce CYP1A1 transcription by binding to the xenobiotic responsive element (XRE). However, the mechanism of activation of the CYP1A1 promoter region is poorly understood. Previous reports showed that Sp1 could bind to a GC-rich region near the CYP1A1 promoter. This study sought to clarify the function of Sp1 in CYP1A1 transcription. Phosphorylation of Sp1 at Ser-59 (pSer-59) was previously reported to be closely related to transcriptional regulation. We used a site-specific phospho-antibody to show that treatment with TCDD or OP drastically reduced the level of pSer-59 in Sp1 from HepG2 cells. This reduction was too much, we hypothesized that the reduced phosphorylation level resulted from activation of phosphatase activity. Given that pSer-59 is dephosphorylated by PP2A, we examined the effect of a PP2A inhibitor, okadaic acid (OA), on pSer-59 and transcription of CYP1A1. The results showed that OA blocked dephosphorylation of Ser-59 and drastically inhibited transcription of CYP1A1. Similar results were obtained after knockdown of PP2A. Treatment with OA had no effect on the expression of AhR, its nuclear translocation, or its ability to bind to the XRE. Furthermore, dephosphorylation of Sp1 at Ser-59 was not affected by knockdown of AhR. These results indicate that the signals from TCDD or OP caused PP2A-mediated dephosphorylation of Sp1 at Ser-59 and induced CYP1A1 transcription. This signaling pathway was independent of the AhR-mediated pathway.
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Safe S, Lee SO, Jin UH. Role of the aryl hydrocarbon receptor in carcinogenesis and potential as a drug target. Toxicol Sci 2013; 135:1-16. [PMID: 23771949 PMCID: PMC3748760 DOI: 10.1093/toxsci/kft128] [Citation(s) in RCA: 205] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 06/03/2013] [Indexed: 12/22/2022] Open
Abstract
The aryl hydrocarbon receptor (AHR) is highly expressed in multiple organs and tissues, and there is increasing evidence that the AHR plays an important role in cellular homeostasis and disease. The AHR is expressed in multiple tumor types, in cancer cell lines, and in tumors from animal models, and the function of the AHR has been determined by RNA interference, overexpression, and inhibition studies. With few exceptions, knockdown of the AHR resulted in decreased proliferation and/or invasion and migration of cancer cell lines, and in vivo studies in mice overexpressing the constitutively active AHR exhibited enhanced stomach and liver cancers, suggesting a pro-oncogenic role for the AHR. In contrast, loss of the AHR in transgenic mice that spontaneously develop colonic tumors and in carcinogen-induced liver tumors resulted in increased carcinogenesis, suggesting that the receptor may exhibit antitumorigenic activity prior to tumor formation. AHR ligands also either enhanced or inhibited tumorigenesis, and these effects were highly tumor specific, demonstrating that selective AHR modulators that exhibit agonist or antagonist activities represent an important new class of anticancer agents that can be directed against multiple tumors.
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Affiliation(s)
- Stephen Safe
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, Texas 77843-4466, USA.
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15
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Patri M, Singh A, Mallick BN. Protective role of noradrenaline in benzo[a]pyrene-induced learning impairment in developing rat. J Neurosci Res 2013; 91:1450-62. [PMID: 23996611 DOI: 10.1002/jnr.23265] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 05/09/2013] [Accepted: 05/22/2013] [Indexed: 01/12/2023]
Abstract
Benzo[a]pyrene (B[a]P), a carcinogen, affects brain development, learning, and memory. Isolated studies have reported that B[a]P elevates noradrenaline (NA) level that may modulate neuronal growth, learning, and memory. Therefore, we investigated in vivo and in vitro the effects of B[a]P on learning and memory and its possible mechanism of action. Intracisternal administration of B[a]P on postnatal day 5 significantly reduced learning and memory in adolescent rats as observed by probe test using the Morris water maze. The density of both the subunits of the N-methyl-D-aspartate (NMDA) receptor, NMDAR1 and NMDAR2B, significantly increased in the hippocampus. In vitro, B[a]P significantly increased NMDAR1 in both C6 and Neuro2a cell lines, whereas NMDAR2B was significantly increased in C6 but was significantly decreased in Neuro2a. Pretreatment with NA prevented the B[a]P-induced effect on NMDAR1 expression in both cell lines. However, although NA prevented the B[a]P-mediated increase in NMDAR2B expression in C6, it further potentiated the decrease of NMDAR2B in Neuro2a cells. Also, NA prevented the B[a]P-induced increase in intracellular Ca(2+) both in C6 and in Neuro2a. Our findings show that postnatal exposure of developing rats to B[a]P impairs learning and memory even when the rats became adolescent. We also observed that the effects were mediated by elevated intracellular Ca(2+) levels and increased expression of NMDAR; furthermore, NA exerted a protective effect by modulating those factors. NA differentially affects neurons and glia, which may have a compensatory role during toxic insults, especially from B[a]P.
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Affiliation(s)
- Manorama Patri
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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Kasai S, Ishigaki T, Takumi R, Kamimura T, Kikuchi H. Beta-catenin signaling induces CYP1A1 expression by disrupting adherens junctions in Caco-2 human colon carcinoma cells. Biochim Biophys Acta Gen Subj 2013; 1830:2509-16. [PMID: 23174221 DOI: 10.1016/j.bbagen.2012.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 10/15/2012] [Accepted: 11/12/2012] [Indexed: 11/19/2022]
Abstract
BACKGROUND The aryl hydrocarbon (Ah) receptor is one of the best known ligand-activated transcription factors. The present study has focused on the wound-healing process on Ah receptor function. METHODS Depletion of calcium from culture medium of Caco-2 human colon carcinoma cells by transfer to Minimal Essential Medium (Spinner Modification; S-MEM) destroyed adherens junctions and the cells were used as the model of wound-healing process. RESULTS Calcium depletion induced both nuclear translocation of the Ah receptor, and increased expression of CYP1A1 and Slug mRNAs in Caco-2 cells. However, expression of Slug mRNA was not significantly induced by treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin. Knockdown of the Ah receptor and treatment with Ah receptor antagonists decreased level of CYP1A1 mRNA. The fragment of E-cadherin released by gamma-secretase was not involved in induction of CYP1A1 mRNA following S-MEM treatment. Knockdown of beta-catenin increased levels of Ah receptor mRNA, which may be attributable to direct or indirect involvement of beta-catenin in suppression of the Ah receptor gene. CONCLUSIONS Our results suggest that mRNA induction of some genes by destruction of adherens junctions depends on the Ah receptor. beta-Catenin, one of the components of the adherens junction, was released from the E-cadherin complex, which resulted in its increased interaction with the Ah receptor, and was translocated into the nucleus, and consequently the target genes would be transcribed. GENERAL SIGNIFICANCE Our observations suggest that some aspects of the molecular mechanism of wound healing involve the Ah receptor.
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Affiliation(s)
- Shuya Kasai
- Science of Biosources, United Graduate School of Agricultural Science, Iwate University, Morioka 020-8551, Japan
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Hur D, Jeon JK, Hong S. Analysis of immune gene expression modulated by benzo[a]pyrene in head kidney of olive flounder (Paralichthys olivaceus). Comp Biochem Physiol B Biochem Mol Biol 2013; 165:49-57. [DOI: 10.1016/j.cbpb.2013.03.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 02/26/2013] [Accepted: 03/03/2013] [Indexed: 11/16/2022]
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Schulz M, Brandner S, Eberhagen C, Eckardt-Schupp F, Larsen MR, Andrae U. Quantitative phosphoproteomic analysis of early alterations in protein phosphorylation by 2,3,7,8-tetrachlorodibenzo-p-dioxin. J Proteome Res 2013; 12:866-82. [PMID: 23298284 DOI: 10.1021/pr3009429] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A comprehensive quantitative analysis of changes in protein phosphorylation preceding or accompanying transcriptional activation by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in 5L rat hepatoma cells was performed using the SILAC approach. Following exposure of the cells to DMSO or 1 nM TCDD for 0.5 to 2 h, 5648 phosphorylated peptides corresponding to 2156 phosphoproteins were identified. Eight peptides exhibited a statistically significantly altered phosphorylation because of TCDD exposure and 22 showed a regulation factor of ≥ 1.5 in one of the experiments per time point. The vast majority of the TCCD-induced phosphorylation changes had not been reported before. The transcription factor ARNT, the obligate partner for gene activation by the TCDD-bound Ah receptor, exhibited an up-regulation of its Ser77 phosphorylation, a modification known to control the differential binding of ARNT homodimers and heterodimers to different enhancers suggesting that this phosphorylation represents a novel mechanism contributing to the alteration of gene expression by TCDD. Other proteins with altered phosphorylation included, among others, various transcriptional coregulators previously unknown to participate in TCDD-induced gene activation, regulators of small GTPases of the Ras superfamily, UBX domain-containing proteins and the oncogenic protein LYRIC. The results open up new directions for research on the molecular mechanisms of dioxin action and toxicity.
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Affiliation(s)
- Melanie Schulz
- Institute of Molecular Toxicology and Pharmacology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
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Hur D, Hong S. Cloning and characterization of a fish specific gelsolin family gene, ScinL, in olive flounder (Paralichthys olivaceus). Comp Biochem Physiol B Biochem Mol Biol 2012; 164:89-98. [PMID: 23159325 DOI: 10.1016/j.cbpb.2012.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Revised: 11/07/2012] [Accepted: 11/07/2012] [Indexed: 12/23/2022]
Abstract
Scinderin like (ScinL) gene is a unique gelsolin family gene found only in fish. In this study ScinL gene was cloned in olive flounder for the first time and characterized its expression and function. Flounder ScinL cDNA consists of 2911 nucleotides encoding a putative protein of 720 amino acids (79.4 kDa). In phylogenetic analysis, flounder ScinL is closely related to ScinL of zebra fish, anableps, and fugu with the similarity of 51-72%. Fish ScinLs are positioned between gelsolin and scinderin of other species. Flounder ScinL protein has the highly conserved actin and PIP2 binding sites, Ca(2+) coordination site, and a C-terminal latch helix preventing the activation of ScinL protein in the absence of Ca(2+). Putative binding sites for NFAT and AP-1 were found in 5' flanking region. Constitutive ScinL expression was found in most organs and the expression level was higher in gill, head kidney, trunk kidney, spleen and skin than muscle, stomach, intestine and brain. In Q-PCR analysis ScinL and CYP1A1 gene expression were significantly upregulated by BaP in head kidney in vivo and in vitro, and in macrophage cells. Upregulated ScinL expression by BaP was blocked by EGTA, indicating a calcium dependent regulation of ScinL expression.
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Affiliation(s)
- Deokhwe Hur
- Department of Marine Biotechnology, Gangneung Wonju National University, Gangneung 210-702, South Korea
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Mayati A, Le Ferrec E, Lagadic-Gossmann D, Fardel O. Aryl hydrocarbon receptor-independent up-regulation of intracellular calcium concentration by environmental polycyclic aromatic hydrocarbons in human endothelial HMEC-1 cells. ENVIRONMENTAL TOXICOLOGY 2012; 27:556-62. [PMID: 21452393 DOI: 10.1002/tox.20675] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) such as benzo(a)pyrene (B(a)P) constitute a major family of widely-distributed environmental toxic contaminants, known as potent ligands of the aryl hydrocarbon receptor (AhR). B(a)P has been recently shown to trigger an early and transient increase of intracellular calcium concentration ([Ca(2+)](i)), involved in AhR-related up-regulation of target genes by B(a)P. This study was designed to determine whether AhR may play a role in [Ca(2+)](i) induction provoked by B(a)P. We demonstrated that, in addition to B(a)P, various PAHs, including pyrene and benzo(e)pyrene, known to not or only very poorly interact with AhR, similarly up-regulated [Ca(2+)](i) in human endothelial HMEC-1 cells. Moreover, α-naphthoflavone, a flavonoïd antagonist of AhR, was also able to induce [Ca(2+)](i). Knocking-down AhR expression in HMEC-1 cells through transfection of siRNAs, was finally demonstrated to not prevent B(a)P-mediated induction of [Ca(2+)](i), whereas it efficiently counteracted B(a)P-mediated induction of the referent AhR target gene cytochrome P-450 1B1. Taken together, these data demonstrate that environmental PAHs trigger [Ca(2+)](i) induction in an AhR-independent manner.
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21
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Lee WYW, Zhou X, Or PMY, Kwan YW, Yeung JHK. Tanshinone I increases CYP1A2 protein expression and enzyme activity in primary rat hepatocytes. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2012; 19:169-176. [PMID: 21899995 DOI: 10.1016/j.phymed.2011.07.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 06/07/2011] [Accepted: 07/26/2011] [Indexed: 05/31/2023]
Abstract
This study investigated the effects of Danshen and its active ingredients on the protein expression and enzymatic activity of CYP1A2 in primary rat hepatocytes. The ethanolic extract of Danshen roots (containing mainly tanshinones) inhibited CYP1A2-catalyzed phenacetin O-deethylation (IC(50)=24.6 μg/ml) in primary rat hepatocytes while the water extract containing mainly salvianolic acid B and danshenshu had no effect. Individual tanshinones such as cryptotanshinone, dihydrotanshinone, tanshinone IIA inhibited the CYP1A2-mediated metabolism with IC(50) values at 12.9, 17.4 and 31.9 μM, respectively. After 4-day treatment of the rat hepatocytes, the ethanolic extract of Danshen and tanshinone I increased rat CYP1A2 activity by 6.8- and 5.2-fold, respectively, with a concomitant up-regulation of CYP1A2 protein level by 13.5- and 6.5-fold, respectively. CYP1A2 induction correlated with the up-regulation of mRNA level of aryl hydrocarbon receptor (AhR), which suggested a positive feedback mechanism of tanshinone I-mediated CYP1A2 induction. A formulated Danshen pill (containing mainly danshensu and salvianolic acid B and the tanshinones) up-regulated CYP1A2 protein expression and enzyme activity, but danshensu and salvianolic acid B, when used individually, did not affect CYP1A2 activity. This study was the first report on the Janus action of the tanshinones on rat CYP1A2 activity.
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Affiliation(s)
- Wayne Y W Lee
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
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22
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Mayati A, Levoin N, Paris H, N'Diaye M, Courtois A, Uriac P, Lagadic-Gossmann D, Fardel O, Le Ferrec E. Induction of intracellular calcium concentration by environmental benzo(a)pyrene involves a β2-adrenergic receptor/adenylyl cyclase/Epac-1/inositol 1,4,5-trisphosphate pathway in endothelial cells. J Biol Chem 2011; 287:4041-52. [PMID: 22167199 DOI: 10.1074/jbc.m111.319970] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Polycyclic aromatic hydrocarbons (PAHs) such as benzo(a)pyrene (B(a)P) are widely distributed environmental contaminants, known as potent ligands of the aryl hydrocarbon receptor (AhR). These chemicals trigger an early and transient increase of intracellular calcium concentration ([Ca(2+)](i)), required for AhR-related effects of PAHs. The mechanisms involved in this calcium mobilization were investigated in the present study. We demonstrated that B(a)P-mediated [Ca(2+)](i) induction was prevented in endothelial HMEC-1 cells by counteracting β2-adrenoreceptor (β2ADR) activity using pharmacological antagonists, anti-β2ADR antibodies, or siRNA-mediated knockdown of β2ADR expression; by contrast, it was strongly potentiated by β2ADR overexpression in human kidney HEK293 cells. B(a)P was shown, moreover, to directly bind to β2ADR, as assessed by in vitro binding assays and molecular modeling. Pharmacological inhibition and/or siRNA-mediated silencing of various signaling actors acting downstream of β2ADR in a sequential manner, such as G protein, adenylyl cyclase, Epac-1 protein, and inositol 1,4,5-trisphosphate (IP(3))/IP(3) receptor, were next demonstrated to prevent B(a)P-induced calcium signal. Inhibition or knockdown of these signaling elements, as well as the use of chemical β-blockers, were finally shown to counteract B(a)P-mediated induction of cytochrome P-450 1B1, a prototypical AhR target gene. Taken together, our results show that B(a)P binds directly to β2ADR and consequently utilizes β2ADR machinery to mobilize [Ca(2+)](i), through activation of a G protein/adenylyl cyclase/cAMP/Epac-1/IP(3) pathway. This β2ADR-dependent signaling pathway activated by PAHs may likely be crucial for PAH-mediated up-regulation of AhR target genes, thus suggesting a contribution of β2ADR to the health-threatening effects of these environmental pollutants.
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Affiliation(s)
- Abdullah Mayati
- INSERM U1085/IRSET, IFR140, Université de Rennes 1, 2 Avenue du Pr. L. Bernard, Rennes 35043, France
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Ma Q. Influence of light on aryl hydrocarbon receptor signaling and consequences in drug metabolism, physiology and disease. Expert Opin Drug Metab Toxicol 2011; 7:1267-93. [DOI: 10.1517/17425255.2011.614947] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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24
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Induction of cytochromes P450 1A1 and 1A2 by tanshinones in human HepG2 hepatoma cell line. Toxicol Appl Pharmacol 2011; 252:18-27. [PMID: 21262253 DOI: 10.1016/j.taap.2011.01.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 01/12/2011] [Accepted: 01/17/2011] [Indexed: 12/31/2022]
Abstract
Diterpenoid tanshinones including tanshinone IIA (TIIA), cryptotanshinone (CTS), tanshinone I (TI) and dihydrotanshinone I (DHTI) are the major bioactive components from Danshen. The major aim of our present study was to investigate the induction potential of these four main components of tanshinones (TIIA, CTS, TI, and DHTI) on the expression of CYP1A1 and CYP1A2 in HepG2 cells. Our results showed that all of these four tanshinones caused a significant time- and concentration-dependent increase in the amount of CYP1A1/2 expression in HepG2 cells. These induction effects were further characterized through transcriptional regulation: the induction of CYP1A1/2 mRNA level by tanshinones was completely blocked by the transcription inhibitor actinomycin D; the expression of CYP1A1/2 heterogeneous nuclear RNA was induced by tanshinone treatment; and CYP1A1 mRNA stability was not influenced by these tanshinones. Interestingly, tanshinones plus B[a]P produced additive/synergistic effect on CYP1A1/2 induction. In addition, the tanshinone-induced CYP1A1/2 expression was abolished by the aryl hydrocarbon receptor (AhR) antagonist resveratrol, suggesting an AhR dependent transcription mechanism. In the reporter gene assay, while TI and DHTI significantly induced AhR-dependent luciferase activity, TIIA and CTS failed to induce this activity. Collectively, the tanshinones could induce CYP1A1 and CYP1A2 expression through transcriptional activation mechanism and exert differential effects on activating AhR in HepG2 cells. Our findings suggest that rational administration of tanshinones should be considered with respect to their effect on AhR and CYP1A1/2 expression.
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A polyacetylene from Gymnaster koraiensis exerts hepatoprotective effects in vivo and in vitro. Food Chem Toxicol 2010; 48:3035-41. [DOI: 10.1016/j.fct.2010.07.035] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Revised: 07/09/2010] [Accepted: 07/26/2010] [Indexed: 02/01/2023]
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26
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Involvement of pregnane X receptor in the regulation of CYP2B6 gene expression by oltipraz in human hepatocytes. Toxicol In Vitro 2010; 24:452-9. [DOI: 10.1016/j.tiv.2009.09.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 09/25/2009] [Accepted: 09/28/2009] [Indexed: 11/24/2022]
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27
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Yun JH, Lee SB, Lee HJ, Kim CY, Kim MA, Sohn YC, Nho CW. Bi-Functional Induction of the Quinone Reductase and Cytochrome P450 1A1 by Youngiasides via Nrf2-ARE and AhR-XRE Pathways. Biol Pharm Bull 2010; 33:1650-7. [DOI: 10.1248/bpb.33.1650] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Ji Ho Yun
- Natural Products Research Center, Gangneung Institute, Korea Institute of Science and Technology
- Faculty of Marine Bioscience and Technology, Gangnung-Wonju National University
| | - Saet Byoul Lee
- Natural Products Research Center, Gangneung Institute, Korea Institute of Science and Technology
| | - Hee Ju Lee
- Natural Products Research Center, Gangneung Institute, Korea Institute of Science and Technology
| | - Chul Young Kim
- Natural Products Research Center, Gangneung Institute, Korea Institute of Science and Technology
| | - Mi Ae Kim
- Faculty of Marine Bioscience and Technology, Gangnung-Wonju National University
| | - Young Chang Sohn
- Faculty of Marine Bioscience and Technology, Gangnung-Wonju National University
| | - Chu Won Nho
- Natural Products Research Center, Gangneung Institute, Korea Institute of Science and Technology
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28
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Han EH, Kim HG, Im JH, Jeong TC, Jeong HG. Up-regulation of CYP1A1 by rutaecarpine is dependent on aryl hydrocarbon receptor and calcium. Toxicology 2009; 266:38-47. [PMID: 19853001 DOI: 10.1016/j.tox.2009.10.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 10/12/2009] [Accepted: 10/12/2009] [Indexed: 01/31/2023]
Abstract
Rutaecarpine is a quinazolinocarboline alkaloid isolated from a traditional Chinese medicinal fruit, Evodia rutaecarpa. In the present study, we investigated the effect of rutaecarpine on CYP1A1 expression mediated by [Ca(2+)] and the AhR pathway in mouse hepatoma Hepa-1c1c7 cells. Rutaecarpine also significantly increased CYP1A1 enzyme activity and mRNA and protein levels. Rutaecarpine markedly induced XRE and AhR binding activity. CH-223191, an AhR antagonist, blocked the rutaecarpine-induced CYP1A1 enzyme activity and mRNA and protein expression. In addition, rutaecarpine remarkably induced the phosphorylation of Ca(2+)/calmodulin (CaM)-dependent protein kinase (CaMK). W7 and BAPTA/AM, a CaM antagonist and an intracellular Ca(2+) chelator, respectively, blocked the rutaecarpine-induced CYP1A1 enzyme activity and mRNA and protein expression. These results indicate that rutaecarpine induces CYP1A1 expression through AhR- and calcium-dependent mechanisms.
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Affiliation(s)
- Eun Hee Han
- Department of Toxicology, College of Pharmacy, Chungnam National University, 220 Gung-dong, Yuseong-Gu, Daejeon 305-764, South Korea
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29
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Phan V, Olusegun George E, Tran QT, Goodwin S, Bodreddigari S, Sutter TR. Analyzing microarray data with transitive directed acyclic graphs. J Bioinform Comput Biol 2009; 7:135-56. [PMID: 19226664 DOI: 10.1142/s0219720009003972] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 09/19/2008] [Accepted: 10/09/2008] [Indexed: 11/18/2022]
Abstract
Post hoc assignment of patterns determined by all pairwise comparisons in microarray experiments with multiple treatments has been proven to be useful in assessing treatment effects. We propose the usage of transitive directed acyclic graphs (tDAG) as the representation of these patterns and show that such representation can be useful in clustering treatment effects, annotating existing clustering methods, and analyzing sample sizes. Advantages of this approach include: (1) unique and descriptive meaning of each cluster in terms of how genes respond to all pairs of treatments; (2) insensitivity of the observed patterns to the number of genes analyzed; and (3) a combinatorial perspective to address the sample size problem by observing the rate of contractible tDAG as the number of replicates increases. The advantages and overall utility of the method in elaborating drug structure activity relationships are exemplified in a controlled study with real and simulated data.
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Affiliation(s)
- Vinhthuy Phan
- Department of Computer Science, The University of Memphis, Memphis, TN 38152, USA.
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30
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Anwar-Mohamed A, Elbekai RH, El-Kadi AOS. Regulation of CYP1A1 by heavy metals and consequences for drug metabolism. Expert Opin Drug Metab Toxicol 2009; 5:501-21. [DOI: 10.1517/17425250902918302] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Abstract
Dithiolethiones are a well-known class of cancer chemopreventive agents; the key mechanism of action of dithiolethiones involves activation of Nrf2 signaling and induction of phase II enzymes. In the past, attention has been focused mainly on 4-methyl-5-pyrazinyl-3H-1,2-dithiole-3-thione (oltipraz), which showed ability as a wide-spectrum inhibitor of chemical carcinogenesis in preclinical models. However, clinical trials of oltipraz have shown questionable efficacy, and at the high doses employed in such studies, significant side effects were observed. Dithiolethiones that are markedly more effective and potent than oltipraz in both induction of phase II enzymes and inhibition of chemical carcinogenesis in preclinical studies have been identified, and these compounds have shown pronounced organ specificity in vivo. Further investigation of these compounds may lead to development of effective and safe agents for cancer prevention in humans.
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Affiliation(s)
- Yuesheng Zhang
- Department of Cancer Prevention and Control, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA.
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Monteiro P, Gilot D, Langouet S, Fardel O. Activation of the aryl hydrocarbon receptor by the calcium/calmodulin-dependent protein kinase kinase inhibitor 7-oxo-7H-benzimidazo[2,1-a]benz[de]isoquinoline-3-carboxylic acid (STO-609). Drug Metab Dispos 2008; 36:2556-63. [PMID: 18755850 DOI: 10.1124/dmd.108.023333] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study was designed to analyze the effects of the Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) inhibitor STO-609 (7-oxo-7H-benzimidazo[2,1-a]benz[de]isoquinoline-3-carboxylic acid) toward the aryl hydrocarbon receptor (AhR) pathway because Ca2+/calmodulin-dependent protein kinase (CaMK) Ialpha, known as a downstream CaMKK effector, has been recently shown to contribute to the AhR cascade. STO-609 failed to alter up-regulation of the AhR target CYP1A1 in response to the potent AhR ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in MCF-7 cells. STO-609, used at a 25 muM concentration known to fully inhibit CaMKK activity, was surprisingly found to markedly induce CYP1A1 expression and activity by itself in MCF-7 cells; it similarly up-regulated various other AhR target genes in human macrophages. STO-609-related CYP1A1 induction was prevented by chemical inhibition or small interfering RNA-mediated knockdown expression of AhR. Moreover, STO-609 was demonstrated to physically interact with the ligand-binding domain of AhR, as assessed by TCDD binding competition assay, and to induce AhR translocation to the nucleus. As already reported for AhR agonists, STO-609 triggered the increase of [Ca2+](i) and activation of CaMKIalpha, whose inhibition through the use of the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester or the CaMK inhibitor KN-93 (2-[N-(2-hydroxyethyl)]-N-(4-methoxybenzenesulfonyl)]amino-N-(4-chlorocinnamyl)-N-methylbenzylamine), respectively, prevented STO-609-mediated CYP1A1 activity induction. Taken together, these results demonstrate that the CaMKK inhibitor STO-609 can act as an AhR ligand and, in this way, fully activates the Ca2+/CaMKIalpha/AhR cascade. Such data, therefore, make unlikely any contribution of CaMKK activity to the AhR pathway and, moreover, suggest that caution may be required when using STO-609 as a specific inhibitor of CaMKKs.
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Affiliation(s)
- Patricia Monteiro
- Unité Propre de Recherche et de l'Enseignement Supérieur SeRAIC/Institut National de la Santé et de la Recherche Médicale U620, Université de Rennes 1, Faculté de Pharmacie, IFR140, Rennes, France
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Sun H, Chow EC, Liu S, Du Y, Pang KS. The Caco-2 cell monolayer: usefulness and limitations. Expert Opin Drug Metab Toxicol 2008; 4:395-411. [PMID: 18433344 DOI: 10.1517/17425255.4.4.395] [Citation(s) in RCA: 317] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND The Caco-2 monolayer has been used extensively for the high-throughput screening of drug permeability and identification of substrates, inhibitors, and inducers of intestinal transporters, especially P-glycoprotein (P-gp). Traditionally, the Caco-2 monolayer is viewed as a single barrier rather than a polarized cell monolayer consisting of metabolic enzymes that are sandwiched between two membrane barriers with distinctly different transporters. OBJECTIVE This review addressed the usefulness and limitations of the Caco-2 cell monolayer in drug discovery and mechanistic studies. METHODS This mini-review covered applications of the Caco-2 monolayer, clarified misconceptions, and critically addressed issues on data interpretation. CONCLUSION The catenary model extends the usefulness of Caco-2 monolayer and provides proper mechanistic insight and data interpretation.
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Affiliation(s)
- Huadong Sun
- University of Toronto, Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, Toronto, M5S 3M2, Canada +1 416 978 6164 ; +1 416 978 8511 ;
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Merrell MD, Jackson JP, Augustine LM, Fisher CD, Slitt AL, Maher JM, Huang W, Moore DD, Zhang Y, Klaassen CD, Cherrington NJ. The Nrf2 activator oltipraz also activates the constitutive androstane receptor. Drug Metab Dispos 2008; 36:1716-21. [PMID: 18474683 DOI: 10.1124/dmd.108.020867] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Oltipraz (OPZ) is a well known inducer of NAD(P)H:quinone oxidoreductase (NQO1) along with other enzymes that comprise the nuclear factor E2-related factor 2 (Nrf2) battery of detoxification genes. However, OPZ treatment also induces expression of CYP2B, a gene regulated by the constitutive androstane receptor (CAR). Therefore, this study was designed to determine whether OPZ induces gene expression in the mouse liver through activation of CAR in addition to Nrf2. OPZ increased the mRNA expression of both Cyp2b10 and Nqo1 in C57BL/6 mouse livers. As expected, in livers from Nrf2-/- mice, OPZ induction of Nqo1 was reduced, indicating Nqo1 induction is dependent on Nrf2 activation, whereas Cyp2b10 induction was unchanged. The robust induction of Cyp2b10 by OPZ in wild-type mice was completely absent in CAR-/- mice, revealing a CAR-dependent induction by OPZ. OPZ also induced transcription of the human CYP2B6 promoter-reporter containing the phenobarbital (PB) responsive element in mouse liver using an in vivo transcription assay. Additionally, OPZ induced in vivo nuclear accumulation of CAR at 3 h but, as with PB, was unable to reverse androstanol repression of mouse CAR constitutive activity in transiently transfected HepG2 cells. In summary, OPZ induces expression of Cyp2b10 and Nqo1 via the activation of CAR and Nrf2, respectively.
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Affiliation(s)
- Matthew D Merrell
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, AZ 85721, USA
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van de Kerkhof EG, de Graaf IAM, Ungell ALB, Groothuis GMM. Induction of metabolism and transport in human intestine: validation of precision-cut slices as a tool to study induction of drug metabolism in human intestine in vitro. Drug Metab Dispos 2007; 36:604-13. [PMID: 18094037 DOI: 10.1124/dmd.107.018820] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Induction of drug enzyme activity in the intestine can strongly determine plasma levels of drugs. It is therefore important to predict drug-drug interactions in human intestine in vitro. We evaluated the applicability of human intestinal precision-cut slices for induction studies in vitro. Morphological examination and intracellular ATP levels indicated tissue integrity up to 24 h of incubation, whereas in proximal jejunum slices, the metabolic rate toward most substrates remained at 40 to 50% of initial values. In colon slices, the cytochrome P450 conversions were below the detection limit, but conjugation rates remained relatively constant during incubation. The inducibility of drug-metabolizing enzymes and P-glycoprotein was evaluated using prototypical inducers for five induction pathways. beta-Naphthoflavone (aryl hydrocarbon receptor ligand) induced CYP1A1 (132-fold in colon and 362-fold in proximal jejunum) and UDP glucuronosyltransferase (UGT) 1A6 mRNA (9.8-fold in colon and 3.2-fold in proximal jejunum). In proximal jejunum, rifampicin (RIF) [pregnane X receptor (PXR) ligand] induced CYP3A4 (5.2-fold), CYP2B6 (2-fold), UGT1A6 (2.2-fold), and multidrug resistance-1 (MDR1)/ABCB1 mRNA (2.7-fold), whereas 6beta-hydroxytestosterone formation (CYP3A4) increased 2-fold. In colon, RIF induced UGT1A6 32-fold and MDR1 2.2-fold. Dexamethasone (glucocorticoid receptor and PXR ligand) induced CYP3A4 mRNA (3.5-fold) and activity (5-fold) in proximal jejunum. Phenobarbital (constitutive androstane receptor activator) induced CYP3A4 (4.1-fold, only in jejunum), CYP2B6 (4.9-fold in colon and 2.3-fold in proximal jejunum), and MDR1/ABCB1 mRNA and CYP3A4 activity (2-fold only proximal jejunum). Quercetin (nuclear factor-E2-related factor 2 activator) induced UGT1A6 mRNA (6.7-fold in colon and 2.2-fold in proximal jejunum). In conclusion, this study shows that human intestinal precision-cut slices are useful to study induction of drug-metabolizing enzymes and transporters in the human intestine.
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Affiliation(s)
- Esther G van de Kerkhof
- Department of Pharmacokinetics & Drug Delivery, Groningen Research Institute for Pharmacy, University of Groningen, Groningen, The Netherlands
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36
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Monteiro P, Gilot D, Le Ferrec E, Rauch C, Lagadic-Gossmann D, Fardel O. Dioxin-Mediated Up-Regulation of Aryl Hydrocarbon Receptor Target Genes Is Dependent on the Calcium/Calmodulin/CaMKIα Pathway. Mol Pharmacol 2007; 73:769-77. [DOI: 10.1124/mol.107.043125] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Lee DY, Kim JW, Lee MG. Pharmacokinetic interaction between oltipraz and omeprazole in rats: Competitive inhibition of metabolism of oltipraz by omeprazole via CYP1A1 and 3A2, and of omeprazole by oltipraz via CYP1A1/2, 2D1/2, and 3A1/2. Eur J Pharm Sci 2007; 32:328-39. [DOI: 10.1016/j.ejps.2007.08.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Revised: 08/24/2007] [Accepted: 08/27/2007] [Indexed: 12/11/2022]
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Lin CH, Juan SH, Wang CY, Sun YY, Chou CM, Chang SF, Hu SY, Lee WS, Lee YH. Neuronal activity enhances aryl hydrocarbon receptor-mediated gene expression and dioxin neurotoxicity in cortical neurons. J Neurochem 2007; 104:1415-29. [PMID: 17973980 DOI: 10.1111/j.1471-4159.2007.05098.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor activated by dioxin and polyaromatic hydrocarbons. Recent studies have revealed that AhR activity in central neurons depends on the NMDA receptor. In this study, we investigated how the neuronal activity influence AhR-mediated dioxin-responsive gene expression and neurotoxicity. Our results show that activation of AhR by the selective agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin induced dioxin-responsive gene expression and calcium entry, which were attenuated by AhR small interfering RNA, the NMDA receptor channel blocker MK801, and the action potential blocker tetrodotoxin (TTX). In addition, AhR-mediated gene expression was enhanced in neurons during synaptogenesis (10 days in vitro) compared with younger neurons (4 days in vitro), as was sensitivity to TTX and MK801. Furthermore, TTX and MK801 differentially affected the association of AhR and its transcriptional co-activator cAMP-responsive-element binding protein with the cytochrome P450 1A1 (cyp1A1) gene enhancer. Calcium/calmodulin-dependent protein kinase IV, the cAMP-responsive-element binding protein activating enzyme, was also activated by 2,3,7,8-tetrachlorodibenzo-p-dioxin in an activity-dependent manner. Finally, we found that neuronal susceptibility to dioxin insult was also maturation and activity-dependent. Together, the results suggest that neuronal activity may facilitate AhR-mediated calcium signaling, which in turn enhances AhR-mediated gene regulation and mediated maturation-dependent dioxin neurotoxicity.
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Affiliation(s)
- Chun-Hua Lin
- Division of Cell Physiology and Neuroscience, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
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Dale Y, Eltom SE. The induction of CYP1A1 by oltipraz is mediated through calcium-dependent-calpain. Toxicol Lett 2006; 166:150-9. [PMID: 16891067 DOI: 10.1016/j.toxlet.2006.06.645] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2006] [Revised: 06/12/2006] [Accepted: 06/12/2006] [Indexed: 11/30/2022]
Abstract
The induction of CYP1A1 expression by oltipraz, a synthetic chemo-preventive agent, which increases intracellular calcium concentration, has previously been shown to result from transcriptional activation of CYP1A1 gene mediated by the Ah receptor (AhR), although oltipraz does not bind the receptor. The present study investigated the possible mechanisms of oltipraz-induced activation of AhR and the subsequent induction of CYP1A1 transcription. Treatment of the human metastatic breast cancer cell line MT-2 with oltipraz results in a concentration-dependent increase in the activity of the calcium-dependent calpain, as measured towards the BOC-LM-CMAC fluorescent substrate. This increase in calpain activity was coupled with the AhR activation, as evidenced by its nuclear localization and increased transcription of CYP1A1 gene. Treatment of cells with calpain specific inhibitor MDL 28170 completely blocked the oltipraz-induced nuclear translocation of AhR and subsequent CYP1A1 expression. Furthermore, treatment with oltipraz resulted in the classical ligand-dependent down-regulation of AhR protein, in a concentration dependent manner. The presented data established for the first time a mechanism of activating AhR and its transcription of CYP1A1 by oltipraz through activation of calcium-dependent calpain.
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Affiliation(s)
- Yolanda Dale
- Graduate Program in Pharmacology, Meharry Medical College, Nashville, TN 37208, USA
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Dale YR, Eltom SE. Calpain Mediates the Dioxin-Induced Activation and Down-Regulation of the Aryl Hydrocarbon Receptor. Mol Pharmacol 2006; 70:1481-7. [PMID: 16891617 DOI: 10.1124/mol.106.027474] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated basic-helix-loop-helix transcription factor that binds polyaromatic hydrocarbons (PAH), such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and mediates their toxicity. Binding of PAH to AhR in the cytoplasm triggers a poorly defined transformation step of the receptor into a nuclear transcription factor. In this study, we show that the calcium-dependent cysteine protease calpain plays a major role in the ligand-induced transformation and signaling of AhR. Fluorescence imaging measurements showed that TCDD treatment elevates intracellular calcium, providing the trigger for calpain activation, as measured toward t-butoxycarbonyl-Leu-Met-chloromethylaminocoumarin, a calpain-specific substrate. Inhibition of calpain activity by the N-benzyloxycarbonyl-Val-Phe-aldehyde (MDL28170) blocked the TCDD-induced nuclear translocation of AhR in Hepa1c1c7 mouse hepatoma cell line. Treatment of the human metastatic breast carcinoma cell line MT-2 with MDL28170 and 3-(4-iodophenyl)-2-mercapto-(Z)-2-propenoic acid (PD 150606), two calpain-selective inhibitors, completely abolished the TCDD-induced transactivation of AhR as assessed by transcription of CYP1A1 gene. Previous studies have established that after TCDD-induced transactivation, the AhR undergoes a massive depletion; we show here that selective calpain inhibitors can block this step, which suggests that the ligand-induced down-regulation of the AhR is calpain-dependent. The data presented support a major role for calpain in the AhR transformation, transactivation, and subsequent down-regulation, and provide a possible explanation for many of the reported phenomena of ligand-independent activation of AhR.
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Affiliation(s)
- Yolanda R Dale
- Graduate Program in Pharmacology, Meharry Medical College, Nashville, Tennessee, USA
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Jigorel E, Le Vee M, Boursier-Neyret C, Parmentier Y, Fardel O. Differential regulation of sinusoidal and canalicular hepatic drug transporter expression by xenobiotics activating drug-sensing receptors in primary human hepatocytes. Drug Metab Dispos 2006; 34:1756-63. [PMID: 16837569 DOI: 10.1124/dmd.106.010033] [Citation(s) in RCA: 234] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Sinusoidal and canalicular hepatic drug transporters constitute key factors involved in drug elimination from liver. Regulation of their expression via activation of xenosensors, such as aryl hydrocarbon receptor (AhR), constitutive androstane receptor (CAR), pregnane X receptor (PXR), and nuclear factor E2-related factor 2 (Nrf2), remains incompletely characterized. The present study was therefore designed to carefully analyze expression of major drug transporters in primary human hepatocytes exposed to dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD) (an AhR activator), rifampicin (RIF) (a PXR activator), phenobarbital (PB) (a CAR activator), and oltipraz (OPZ) (a Nrf2 activator), using mainly reverse transcription-real time polymerase chain reaction assays. With a threshold corresponding to a 1.5-fold factor change in mRNA levels, observed in at least three of seven independent human hepatocyte cultures, efflux transporters such as MDR1, MRP2 and BCRP were up-regulated by PB, RIF, and OPZ, whereas MRP3 was induced by OPZ and RIF. MDR1 and BCRP expression was also increased by TCDD- and RIF-augmented mRNA levels of the influx transporter OATP-C. Bile acid transporters, i.e., bile salt export pump and Na(+)-taurocholate cotransporting polypeptide, and the sinusoidal transporter, OAT2, were down-regulated by all the tested chemicals. Influx transporters such as OCT1, OATP-B, and OATP8 were repressed by PB and TCDD. PB also decreased MRP6 expression, whereas mRNA levels of OCT1 and OATP8 were down-regulated by RIF and OPZ, respectively. Taken together, these data establish a complex pattern of transporter regulation by xenobiotics in human hepatocytes, in addition to interindividual variability in responsiveness. This may deserve further attention with respect to drug-drug interactions and adverse effects of hepatic drugs.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics
- ATP Binding Cassette Transporter, Subfamily G, Member 2
- ATP-Binding Cassette Transporters/genetics
- Adult
- Constitutive Androstane Receptor
- Gene Expression Regulation/drug effects
- Hepatocytes/cytology
- Hepatocytes/drug effects
- Hepatocytes/metabolism
- Humans
- Membrane Transport Proteins/genetics
- Multidrug Resistance-Associated Protein 2
- Multidrug Resistance-Associated Proteins/genetics
- NF-E2-Related Factor 2/genetics
- Neoplasm Proteins/genetics
- Phenobarbital/pharmacology
- Polychlorinated Dibenzodioxins/pharmacology
- Pregnane X Receptor
- Pyrazines/pharmacology
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Aryl Hydrocarbon/drug effects
- Receptors, Aryl Hydrocarbon/metabolism
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Drug/genetics
- Receptors, Steroid/genetics
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Rifampin/pharmacology
- Symporters/genetics
- Thiones
- Thiophenes
- Transcription Factors/genetics
- Xenobiotics/pharmacology
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Affiliation(s)
- Emilie Jigorel
- Institut National de la Santé et de la Recherche Médicale, Faculté de Pharmacie, Rennes, France
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N'Diaye M, Le Ferrec E, Lagadic-Gossmann D, Corre S, Gilot D, Lecureur V, Monteiro P, Rauch C, Galibert MD, Fardel O. Aryl hydrocarbon receptor- and calcium-dependent induction of the chemokine CCL1 by the environmental contaminant benzo[a]pyrene. J Biol Chem 2006; 281:19906-15. [PMID: 16679317 DOI: 10.1074/jbc.m601192200] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are widely distributed immunotoxic environmental contaminants well known to regulate expression of pro-inflammatory cytokines such as interleukine-1beta and tumor necrosis factor-alpha. In the present study, we demonstrated that the chemokine CCL1, notably involved in cardiovascular diseases and inflammatory or allergic processes, constitutes a new molecular target for PAHs. Indeed, exposure to PAHs such as benzo[a]pyrene (BP) markedly increased mRNA expression and secretion of CCL1 in primary human macrophage cultures. Moreover, intranasal administration of BP to mice enhanced mRNA levels of TCA3, the mouse orthologue of CCL1, in lung. CCL1 induction in cultured human macrophages was fully prevented by targeting the aryl hydrocarbon receptor (AhR) through chemical inhibition or small interfering RNA-mediated down-modulation of its expression. In addition, BP and the potent AhR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin were found to enhance activity of a CCL1 promoter sequence containing a consensus xenobiotic-responsive element known to specifically interact with AhR. Moreover, 2,3,7,8-tetrachlorodibenzo-p-dioxin triggered AhR binding to this CCL1 promoter element as revealed by chromatin immunoprecipitation experiments and electrophoretic mobility shift assays. In an attempt to further characterize the mechanism of CCL1 induction, we demonstrated that BP was able to induce an early and transient increase of intracellular calcium concentration in human macrophages. Inhibition of this calcium increase, using the calcium chelator 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetra(acetoxymethyl) ester or the calcium store-operated channel inhibitor 2-aminoethoxydiphenyl borate, fully blocked CCL1 up-regulation. Taken together, these results bring the first demonstration that PAHs induce expression of the chemokine CCL1 in an AhR- and calcium-dependent manner.
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Affiliation(s)
- Monique N'Diaye
- INSERM U620, Unité Mixte de Recherche 6061, Laboratoire de Génétique et Développement, Facultéde Médecine, Université de Rennes 1, IFR140, 35043 Rennes Cedex
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Schreiber TD, Köhle C, Buckler F, Schmohl S, Braeuning A, Schmiechen A, Schwarz M, Münzel PA. REGULATION OFCYP1A1GENE EXPRESSION BY THE ANTIOXIDANTTERT-BUTYLHYDROQUINONE. Drug Metab Dispos 2006; 34:1096-101. [PMID: 16581943 DOI: 10.1124/dmd.106.009662] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
CYP1A1, a major phase I enzyme, plays an important role in the metabolism of polycyclic aromatic hydrocarbons and in the chemical activation of xenobiotics to carcinogenic derivatives. The phenolic antioxidant tert-butylhydroquinone (tBHQ), often used as a food preservative, is generally considered to act only as a mono-functional inducer of phase II enzymes, thereby exerting chemo-protection. However, we recently observed that tBHQ elevated the activity of an aryl hydrocarbon receptor (AhR) response element (DRE)-driven luciferase reporter in human colon carcinoma cells (Caco-2). Therefore, we studied the effects of tBHQ on the activity of a DRE-driven reporter, CYP1A1 mRNA expression, and CYP1A enzyme activity in Caco-2 cells and human HepG2 hepatoma cells. We found tBHQ caused induction of reporter activity and CYP1A1 expression and activity in Caco-2 and HepG2 cells. Moreover, tBHQ combined with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) increased reporter activity and mRNA expression in Caco-2 cells in an additive manner. By contrast, tBHQ decreased TCDD-mediated induction of reporter activity and CYP1A1 mRNA expression in HepG2 cells. Resveratrol, an AhR antagonist, repressed the induction of CYP1A1 by tBHQ. Cotransfection of HepG2 cells with a dominant negative AhR nuclear translocator mutant abolished the tBHQ-induced CYP1A1 reporter activity. These findings indicate that CYP1A1 may be induced by the antioxidant tBHQ via an AhR-dependent mechanism.
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Affiliation(s)
- Thomas D Schreiber
- Institute of Pharmacology and Toxicology, Department of Toxicology, University of Tübingen, Tübingen, Germany
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Shin SM, Cho IJ, Kim SG. CCAAT/enhancer binding protein activation by PD98059 contributes to the inhibition of AhR-mediated 3-methylcholanthrene induction of CYP1A1. Xenobiotica 2006; 35:975-87. [PMID: 16393856 DOI: 10.1080/00498250500354584] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
2'-Amino-3'-methoxyflavone (PD98059), an MKK1 inhibitor, negatively regulates the induction of the CYP1A1 gene by polycyclic aromatic hydrocarbons. In view of the observations that PD98059 inhibits AhR-mediated CYP1A1 induction and has the capability to activate C/EBPbeta, the study investigated whether the inhibition by PD98059 of 3-MC induction of CYP1A1 results from C/EBP activation. 3-MC induction of the CYP1A1 and the CYP1A1 promoter-luciferase gene were inhibited by treatment of H4IIE cells with PD98059. PD98059 treatment inhibited 3-MC-induced AhR binding to the XRE, but increased protein binding to the CYP1A1 C/EBP binding site. PD98059 inhibited 3-MC induction of CYP1A1 in cells stably transfected with a dominant negative mutant of MKK1, indicating that PD98059 represses CYP1A1 induction by 3-MC irrespective of its MKK1 inhibition. The role of C/EBP activation by PD98059 in repressing CYP1A1 induction was supported by the observation that a dominant-negative mutant C/EBP abolished the ability of PD98059 to suppress 3-MC induction of CYP1A1.
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Affiliation(s)
- S M Shin
- National Research Laboratory, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of South Korea
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Krusekopf S, Roots I. St. John's wort and its constituent hyperforin concordantly regulate expression of genes encoding enzymes involved in basic cellular pathways. Pharmacogenet Genomics 2005; 15:817-29. [PMID: 16220113 DOI: 10.1097/01.fpc.0000175597.60066.3d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES AND METHODS The effects of St. John's wort and hyperforin on gene expression were analysed in HepG2 cells by Affymetrix microarray hybridization and real time reverse transcription-PCR. RESULTS Both compounds increased mRNAs of the drug metabolizing enzymes CYP3A4, CYP1A1, CYP1A2 and the flavin containing monooxygenase FMO5, and of the multidrug resistance protein MRP2. CYP4F2 and the reduced nicotinamide adenine dinucleotide dehydrogenase NQO1 were downregulated. Expression of genes mediating cholesterol biosynthesis was decreased, while facilitated glucose transporters and glycolysis genes were induced, indicating increased glucose metabolism. Changes of a considerable number of additional transcripts corresponded to reports on gene regulation by hypoxia. Endoplasmic reticulum stress-regulated genes involved in unfolded protein response and in protection of cells from apoptosis were downregulated. Other calcium binding proteins were affected by both treatments, suggesting an increase in intracellular calcium. CONCLUSIONS St. John's wort and hyperforin concordantly affected expression of genes not only mediating metabolism and transport of exogenous and endogenous compounds, but also involved in energy metabolism, intracellular calcium regulation, cell proliferation and apoptosis.
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Affiliation(s)
- Solveigh Krusekopf
- Institute of Clinical Pharmacology, Charité Campus Mitte, Charité University Medical Center, Humboldt University of Berlin, Berlin, Germany.
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Gross-Steinmeyer K, Stapleton PL, Tracy JH, Bammler TK, Lehman T, Strom SC, Eaton DL. Influence of Matrigel-overlay on constitutive and inducible expression of nine genes encoding drug-metabolizing enzymes in primary human hepatocytes. Xenobiotica 2005; 35:419-38. [PMID: 16012075 DOI: 10.1080/00498250500137427] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
1. Previous studies reported that rat hepatocytes overlaid with extracellular matrix components (Matrigel) maintain the expression and responsiveness of drug-metabolizing enzymes. However, whether Matrigel provides similar advantages in human hepatocytes remains largely uncertain.2. The influence of Matrigel-overlay on the constitutive and phenobarbital- and oltipraz-inducible expression of nine biotransformation enzymes, cytochrome P450s 1A1, 1A2, 2B6, 3A4, and glutathione S-transferases A1, A2, M1, T1, P1, in primary human hepatocytes was evaluated.3. Hepatocytes from five livers were maintained on a rigid collagen substratum with or without Matrigel overlay and treated for 48?h with two doses of each inducer. Quantitative RT-PCR, and for selected genes, immunoblot and enzyme activity analyses, demonstrated that human hepatocytes overlaid with Matrigel showed consistently higher constitutive and inducible expression of biotransformation genes. 4. Phenobarbital-mediated responsiveness of cytochrome P450 2B6, a potential indicator of hepatocyte differentiation status, was markedly higher in overlaid relative to non-overlaid hepatocytes. 5. It is concluded that an Matrigel overlay facilitates the maintenance and induction of xenobiotic metabolizing enzymes in primary cultures of human hepatocytes.
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Affiliation(s)
- K Gross-Steinmeyer
- Department of Environmental and Occupational Health Sciences, Center for Ecogenetics & Environmental Health, University of Washington, Seattle, WA 98105, USA
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Wu ML, Li H, Wu DC, Wang XW, Chen XY, Kong QY, Ma JX, Gao Y, Liu J. CYP1A1 and CYP1B1 expressions in medulloblastoma cells are AhR-independent and have no direct link with resveratrol-induced differentiation and apoptosis. Neurosci Lett 2005; 384:33-7. [PMID: 15893423 DOI: 10.1016/j.neulet.2005.04.055] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Revised: 03/19/2005] [Accepted: 04/14/2005] [Indexed: 10/25/2022]
Abstract
Resveratrol induces apoptosis and regulates CYP1A1 and CYP1B1 expression in human medulloblastoma cells. To elucidate the potential correlation of their expressions with the anti-medulloblastoma effects of resveratrol, human medulloblastoma cells, UW228-3, were treated with CYP1A1 selective inhibitor (alpha-naphthoflavone, alpha-NF), selective CYP1A1/1A2 inducer (beta-naphthoflavone, beta-NF) and their combination with resveratrol, respectively. The influences of those treatments on the expressions of CYP1A1, 1A2 and 1B1 as well as the cell growth, differentiation and death were analyzed. It was found that neither alpha-NF nor beta-NF had any effect on cell growth. alpha-NF inhibited resveratrol-induced CYP1A1 expression without interfering cell differentiation and apoptosis. beta-NF could up-regulate resveratrol-induced CYP1A1 expression but not enhance the anti-cancer effects of resveratrol. CYP1A2 was undetectable in the cells irrespective to the treatments. Aryl hydrocarbon receptor (AhR) was absent in UW228-3 cells under normal culture and treated with resveratrol but induced by both alpha- and beta-NF. Immunohistochemical examination performed on 11 pairs of human medulloblastoma and noncancerous cerebellar tissues revealed that AhR was undetectable in either of them, whereas CYP1A1 was expressed in cerebellum but down-regulated or diminished in their malignant counterparts. Our data suggest for the first time that CYP1A1 and 1B1 expressions in human medulloblastoma cells are AhR-independent and have no direct links with resveratrol-induced differentiation and apoptosis. Appearance of CYP1A1 expression may reflect a more maturated status and a better prognosis of medulloblastomas.
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Affiliation(s)
- Mo-Li Wu
- Cancer Institute and Liaoning Laboratory of Cancer Genomics, College of Basic Medical Sciences, Dalian Medical University, Zhanshan Road 465, 6027 Dalian, PR China
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48
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Ebert B, Seidel A, Lampen A. Identification of BCRP as transporter of benzo[ a ]pyrene conjugates metabolically formed in Caco-2 cells and its induction by Ah-receptor agonists. Carcinogenesis 2005; 26:1754-63. [PMID: 15917307 DOI: 10.1093/carcin/bgi139] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Breast cancer resistance protein (BCRP/ABCG2) is known to actively transport various anticancer drugs and to restrict the uptake of the food carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine from the gut lumen. The present study reveals that BCRP is involved in the transport of phase-2 metabolites of the carcinogen benzo[a]pyrene (BP) in the human intestinal cell line Caco-2. Treatment with the selective BCRP inhibitor Ko 143 (5 microM) inhibited the apical transport of BP-3-sulfate (BP3S) to 83% of control levels in TC7 cells and to 64% of control levels in Caco-2 cells. The apical transport of BP-3-glucuronide was inhibited by Ko 143 to 76% of control levels in TC7 cells. Furthermore, the expression of BCRP is most likely aryl hydrocarbon receptor (AhR) dependent, as treatment of Caco-2 cells with known AhR agonists including 2,3,7,8-tetrachlorodibenzo-p-dioxin, BP, indolo[3,2-b]carbazole and benzo[k]fluoranthene increased both mRNA and protein levels of BCRP. Induced BCRP protein was found to be functionally active, since pre-treatment of TC7 cells with oltipraz, indolo[3,2-b]carbazole or benzo[k]fluoranthene increased the amount of apically transported BP3S to as much as 180% of that in the controls. The induction of BCRP (mRNA and protein expression) by indolo[3,2-b]carbazole was inhibited in Caco-2 cells by co-incubation with the AhR antagonist PD98059 (2'-amino-3'-methoxyflavone). In summary, this study provides strong evidence that BCRP is an important part of the intestinal barrier protecting the body from food-associated contaminants such as the carcinogen BP.
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Affiliation(s)
- Bettina Ebert
- Institute for Food Toxicology, University of Veterinary Medicine Hannover, Foundation, Bischofsholern Damm 15/115, 30173 Hannover, Germany
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Leung YK, Lau KM, Mobley J, Jiang Z, Ho SM. Overexpression of Cytochrome P450 1A1 and Its Novel Spliced Variant in Ovarian Cancer Cells: Alternative Subcellular Enzyme Compartmentation May Contribute to Carcinogenesis. Cancer Res 2005; 65:3726-34. [PMID: 15867368 DOI: 10.1158/0008-5472.can-04-3771] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Epithelial ovarian cancer derived from the human ovarian surface epithelium (HOSE) is the leading cause of death from gynecologic malignancies among American women. Metabolic activation of endogenous and exogenous chemicals by cytochrome P450 (CYP) class I enzymes has been implicated in its etiology. In this study, we showed overexpression of CYP1A1 mRNA, but not CYP1B1 transcripts, in ovarian cancer cell lines when compared with primary cultures or immortalized HOSE cell lines. Importantly, we identified a novel, enzymatically active, spliced variant of CYP1A1 (CYP1A1v) formed by excision of an 84-bp cryptic intron in exon 2. CYP1A1v is overexpressed in ovarian cancer cell lines and exhibits a unique subcellular distribution restricted to the nucleus and mitochondria, contrary to the endoplasmic reticulum localization of the wild-type enzyme. In concordance, total CYP1A1 activity, as measured by the ethoxyresorufin O-deethylase assay, was detected in mitochondrial, nuclear, and microsomal fractions of ovarian cancer cells but was notably absent in all subcellular fractions of HOSE cells. Immunocytochemistry studies in 30 clinical specimens revealed overexpression of CYP1A1 in various types of ovarian cancers compared with benign epithelia and frequent localization of the enzyme to cancer cell nuclei. Forced expression of CYP1A1wt or CYP1A1v in HOSE cells resulted in nuclear localization of the enzyme and acquisition of anchorage-independent growth, which was further exacerbated following exposure to benzo(a)pyrene or 17beta-estradiol. Collectively, these data provided the first evidence that CYP1A1 overexpression and alternative splicing could contribute to ovarian cancer initiation and progression.
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Affiliation(s)
- Yuet-Kin Leung
- Department of Surgery, University of Massachusetts Medical School, Worcester, Massachusetts 01605-2324, USA
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Konwinski RR, Haddad R, Chun JA, Klenow S, Larson SC, Haab BB, Furge LL. Oltipraz, 3H-1,2-dithiole-3-thione, and sulforaphane induce overlapping and protective antioxidant responses in murine microglial cells. Toxicol Lett 2004; 153:343-55. [PMID: 15454310 DOI: 10.1016/j.toxlet.2004.06.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2004] [Revised: 06/12/2004] [Accepted: 06/14/2004] [Indexed: 11/24/2022]
Abstract
Oltipraz (OPZ) is a known inducer of glutathione S-transferases and a mechanism-based inhibitor of cytochrome P450 1A2. Given the detoxification characteristics of this compound, the transcriptional effects of OPZ, along with the related naturally occurring compounds 3H-1,2-dithiole-3-thione (D3T) and sulforaphane (SF), were examined by gene expression profiling in murine BV-2 microglial cells, a neuronal macrophage cell type that mediates inflammatory responses in the brain. We show that the three compounds generate largely overlapping transcriptional changes in genes that are associated with detoxification and antioxidant responses. In addition, induction of an antioxidant/detoxification response in the microglial cells by OPZ, D3T, or SF was also able to protect cells from H2O2 -induced toxicity and to attenuate the production of reactive oxygen species in response to lipopolysaccharide treatment of cells. These results show that OPZ, D3T, and SF activate overlapping changes in gene expression and that they can regulate detoxification/antioxidant responses in multiple cells types, including cell types known to have a role in the production of oxidative stress.
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Affiliation(s)
- Ryan R Konwinski
- Department of Chemistry, Kalamazoo College, 1200 Academy Street, Kalamazoo, MI 49006, USA
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