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Rigalli JP, Theile D, Nilles J, Weiss J. Regulation of PXR Function by Coactivator and Corepressor Proteins: Ligand Binding Is Just the Beginning. Cells 2021; 10:cells10113137. [PMID: 34831358 PMCID: PMC8625645 DOI: 10.3390/cells10113137] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 12/13/2022] Open
Abstract
The pregnane X receptor (PXR, NR1I2) is a nuclear receptor which exerts its regulatory function by heterodimerization with the retinoid-X-receptor α (RXRα, NR2B1) and binding to the promoter and enhancer regions of diverse target genes. PXR is involved in the regulation of drug metabolism and excretion, metabolic and immunological functions and cancer pathogenesis. PXR activity is strongly regulated by the association with coactivator and corepressor proteins. Coactivator proteins exhibit histone acetyltransferase or histone methyltransferase activity or associate with proteins having one of these activities, thus promoting chromatin decondensation and activation of the gene expression. On the contrary, corepressor proteins promote histone deacetylation and therefore favor chromatin condensation and repression of the gene expression. Several studies pointed to clear cell- and ligand-specific differences in the activation of PXR. In this article, we will review the critical role of coactivator and corepressor proteins as molecular determinants of the specificity of PXR-mediated effects. As already known for other nuclear receptors, understanding the complex mechanism of PXR activation in each cell type and under particular physiological and pathophysiological conditions may lead to the development of selective modulators with therapeutic potential.
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Fujino C, Sanoh S, Katsura T. Variation in Expression of Cytochrome P450 3A Isoforms and Toxicological Effects: Endo- and Exogenous Substances as Regulatory Factors and Substrates. Biol Pharm Bull 2021; 44:1617-1634. [PMID: 34719640 DOI: 10.1248/bpb.b21-00332] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The CYP3A subfamily, which includes isoforms CYP3A4, CYP3A5, and CYP3A7 in humans, plays important roles in the metabolism of various endogenous and exogenous substances. Gene and protein expression of CYP3A4, CYP3A5, and CYP3A7 show large inter-individual differences, which are caused by many endogenous and exogenous factors. Inter-individual differences can cause negative outcomes, such as adverse drug events and disease development. Therefore, it is important to understand the variations in CYP3A expression caused by endo- and exogenous factors, as well as the variation in the metabolism and kinetics of endo- and exogenous substrates. In this review, we summarize the factors regulating CYP3A expression, such as bile acids, hormones, microRNA, inflammatory cytokines, drugs, environmental chemicals, and dietary factors. In addition, variations in CYP3A expression under pathological conditions, such as coronavirus disease 2019 and liver diseases, are described as examples of the physiological effects of endogenous factors. We also summarize endogenous and exogenous substrates metabolized by CYP3A isoforms, such as cholesterol, bile acids, hormones, arachidonic acid, vitamin D, and drugs. The relationship between the changes in the kinetics of these substrates and the toxicological effects in our bodies are discussed. The usefulness of these substrates and metabolites as endogenous biomarkers for CYP3A activity is also discussed. Notably, we focused on discrimination between CYP3A4, CYP3A5, and CYP3A7 to understand inter-individual differences in CYP3A expression and function.
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Affiliation(s)
- Chieri Fujino
- Laboratory of Clinical Pharmaceutics and Therapeutics, College of Pharmaceutical Sciences, Ritsumeikan University
| | - Seigo Sanoh
- Graduate School of Biomedical and Health Sciences, Hiroshima University.,School of Pharmaceutical Sciences, Wakayama Medical University
| | - Toshiya Katsura
- Laboratory of Clinical Pharmaceutics and Therapeutics, College of Pharmaceutical Sciences, Ritsumeikan University
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Smutny T, Bernhauerova V, Smutna L, Tebbens JD, Pavek P. Expression dynamics of pregnane X receptor-controlled genes in 3D primary human hepatocyte spheroids. Arch Toxicol 2021; 96:195-210. [PMID: 34689256 DOI: 10.1007/s00204-021-03177-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 10/06/2021] [Indexed: 02/07/2023]
Abstract
The pregnane X receptor (PXR) is a ligand-activated nuclear receptor controlling hepatocyte expression of numerous genes. Although expression changes in xenobiotic-metabolizing, lipogenic, gluconeogenic and bile acid synthetic genes have been described after PXR activation, the temporal dynamics of their expression is largely unknown. Recently, 3D spheroids of primary human hepatocytes (PHHs) have been characterized as the most phenotypically relevant hepatocyte model. We used 3D PHHs to assess time-dependent expression profiles of 12 prototypic PXR-controlled genes in the time course of 168 h of rifampicin treatment (1 or 10 µM). We observed a similar bell-shaped time-induction pattern for xenobiotic-handling genes (CYP3A4, CYP2C9, CYP2B6, and MDR1). However, we observed either biphasic profiles for genes involved in endogenous metabolism (FASN, GLUT2, G6PC, PCK1, and CYP7A1), a decrease for SHP or oscillation for PDK4 and PXR. The rifampicin concentration determined the expression profiles for some genes. Moreover, we calculated half-lives of CYP3A4 and CYP2C9 mRNA under induced or basal conditions and we used a mathematical model to describe PXR-mediated regulation of CYP3A4 expression employing 3D PHHs. The study shows the importance of long-term time-expression profiling of PXR target genes in phenotypically stable 3D PHHs and provides insight into PXR function in liver beyond our knowledge from conventional 2D in vitro models.
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Affiliation(s)
- Tomas Smutny
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Kralove, Charles University, Akademika Heyrovskeho 1203, Hradec Kralove, 500 05, Czech Republic.
| | - Veronika Bernhauerova
- Department of Biophysics and Physical Chemistry, Faculty of Pharmacy in Hradec Kralove, Charles University, Akademika Heyrovskeho 1203, Hradec Kralove, 500 05, Czech Republic
| | - Lucie Smutna
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Kralove, Charles University, Akademika Heyrovskeho 1203, Hradec Kralove, 500 05, Czech Republic
| | - Jurjen Duintjer Tebbens
- Department of Biophysics and Physical Chemistry, Faculty of Pharmacy in Hradec Kralove, Charles University, Akademika Heyrovskeho 1203, Hradec Kralove, 500 05, Czech Republic
| | - Petr Pavek
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Kralove, Charles University, Akademika Heyrovskeho 1203, Hradec Kralove, 500 05, Czech Republic
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El-Ghiaty MA, El-Kadi AO. Arsenic: Various species with different effects on cytochrome P450 regulation in humans. EXCLI JOURNAL 2021; 20:1184-1242. [PMID: 34512225 PMCID: PMC8419240 DOI: 10.17179/excli2021-3890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 07/02/2021] [Indexed: 11/22/2022]
Abstract
Arsenic is well-recognized as one of the most hazardous elements which is characterized by its omnipresence throughout the environment in various chemical forms. From the simple inorganic arsenite (iAsIII) and arsenate (iAsV) molecules, a multitude of more complex organic species are biologically produced through a process of metabolic transformation with biomethylation being the core of this process. Because of their differential toxicity, speciation of arsenic-based compounds is necessary for assessing health risks posed by exposure to individual species or co-exposure to several species. In this regard, exposure assessment is another pivotal factor that includes identification of the potential sources as well as routes of exposure. Identification of arsenic impact on different physiological organ systems, through understanding its behavior in the human body that leads to homeostatic derangements, is the key for developing strategies to mitigate its toxicity. Metabolic machinery is one of the sophisticated body systems targeted by arsenic. The prominent role of cytochrome P450 enzymes (CYPs) in the metabolism of both endobiotics and xenobiotics necessitates paying a great deal of attention to the possible effects of arsenic compounds on this superfamily of enzymes. Here we highlight the toxicologically relevant arsenic species with a detailed description of the different environmental sources as well as the possible routes of human exposure to these species. We also summarize the reported findings of experimental investigations evaluating the influence of various arsenicals on different members of CYP superfamily using human-based models.
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Affiliation(s)
- Mahmoud A. El-Ghiaty
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Ayman O.S. El-Kadi
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
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Abbott EA, Helbing CC. Sucralose Affects Thyroid Hormone Signaling in American Bullfrog [Rana (Lithobates) catesbeiana] Tadpoles. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2021; 80:735-744. [PMID: 33787960 DOI: 10.1007/s00244-021-00838-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
Nonnutritive sweeteners used in food and beverage products are widespread, persistent aquatic pollutants. Despite this, their impact on aquatic organisms, particularly vertebrates, is not well-studied. Recent findings in rodents suggest sucralose, a chlorinated disaccharide, alters thyroid hormone (TH) metabolism. Because amphibian tadpole metamorphosis is TH-dependent, we hypothesized sucralose may alter signaling for this postembryonic developmental process. The present study used the American bullfrog, Rana (Lithobates) catesbeiana, as a sensitive, environmentally relevant model for testing TH disruption in the absence and presence of thyroxine (T4), a hormone that induces metamorphosis. Premetamorphic R. catesbeiana tadpoles were immersed in 1-, 15-, and 32-mg/L sucralose solutions ± 5 nM (3.9 µg/L) thyroxine (T4) for 48 h. RNA transcripts encoding thyroid hormone receptors alpha and beta (thra and thrb) and TH-induced basic region leucine zipper protein (thibz) were analyzed in four tissues: back skin, liver, olfactory epithelium, and tail fin, using reverse transcription quantitative real-time PCR (RT-qPCR). We found that sucralose altered the expression of fundamental TH-response genes involved in anuran metamorphosis in a tissue- and TH-status dependent manner. As organochlorines induce xenobiotic metabolism, we isolated and characterized three novel R. catesbeiana gene transcripts involved in xenobiotic metabolism: pregnane X receptor (nr1i2), constitutive androstane receptor (nr1i3), and cytochrome p450 3a4 (cyp3a4). We analyzed their expression using RT-qPCR and found evidence of their modulation by sucralose. To our knowledge, these data are the first to show xenobiotic and thyroid-disrupting activities in amphibians and further investigations into cumulative effects of environmental sucralose exposure are warranted.
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Affiliation(s)
- Ethan A Abbott
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Road, Victoria, BC, V8P 5C2, Canada
| | - Caren C Helbing
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Road, Victoria, BC, V8P 5C2, Canada.
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Neary M, Chappell CA, Scarsi KK, Nakalema S, Matovu J, Achilles SL, Chen BA, Siccardi M, Owen A, Lamorde M. Effect of patient genetics on etonogestrel pharmacokinetics when combined with efavirenz or nevirapine ART. J Antimicrob Chemother 2020; 74:3003-3010. [PMID: 31299074 DOI: 10.1093/jac/dkz298] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/10/2019] [Accepted: 06/12/2019] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND We previously demonstrated that etonogestrel concentrations were 82% lower in women using etonogestrel contraceptive implants plus efavirenz-based ART compared with women not receiving ART. OBJECTIVES To investigate the genetic contribution to this previously observed drug-drug interaction through studying SNPs in genes known to be involved in efavirenz, nevirapine or etonogestrel metabolism in the same group of women. PATIENTS AND METHODS Here, we present a secondary analysis evaluating SNPs involved in efavirenz, nevirapine and etonogestrel metabolism and associated etonogestrel pharmacokinetics among 57 women, 19 not receiving ART (control group), 19 receiving efavirenz- (600 mg daily) based ART and 19 receiving nevirapine- (200 mg twice daily) based ART. Associations between patient genotype and etonogestrel pharmacokinetic parameters were determined through univariate and multivariate linear regression. This study was registered at clinicaltrials.gov (NCT02082652). RESULTS Within the control group, CYP2B6 983 T>C was associated with 27% higher etonogestrel Cmax and 28% higher AUC0-24weeks. In the efavirenz group CYP2B6 516 G>T was associated with 43% lower etonogestrel Cmin and 34% lower AUC0-24weeks. For participants receiving nevirapine, NR1I2 63396 C>T was associated with 39% lower etonogestrel Cmin and 37% lower AUC0-24weeks. CONCLUSIONS This study demonstrates the influence of pharmacogenetics on the extent of drug-drug interactions between etonogestrel and efavirenz- or nevirapine-based ART. Efavirenz plus the etonogestrel contraceptive implant results in a detrimental drug-drug interaction irrespective of patient genetics, which is worsened in women possessing variant alleles for these CYP2B6 SNPs.
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Affiliation(s)
- Megan Neary
- Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Catherine A Chappell
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Kimberly K Scarsi
- Department of Pharmacy Practice and Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, USA
| | - Shadia Nakalema
- Infectious Diseases Institute, Makerere University College of Health Sciences, Kampala, Uganda
| | - Joshua Matovu
- Infectious Diseases Institute, Makerere University College of Health Sciences, Kampala, Uganda
| | - Sharon L Achilles
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Beatrice A Chen
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Marco Siccardi
- Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Andrew Owen
- Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Mohammed Lamorde
- Infectious Diseases Institute, Makerere University College of Health Sciences, Kampala, Uganda
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Albumin is a secret factor involved in multidirectional interactions among the serotoninergic, immune and endocrine systems that supervises the mechanism of CYP1A and CYP3A regulation in the liver. Pharmacol Ther 2020; 215:107616. [PMID: 32590025 DOI: 10.1016/j.pharmthera.2020.107616] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 06/15/2020] [Indexed: 12/25/2022]
Abstract
This review focuses on albumin, which is involved in multidirectional interactions among the immune, endocrine and serotoninergic systems and supervises the regulation of cytochrome P450 (CYP) isoforms under conditions of both normal liver function and liver insufficiency. Special attention is paid to albumin, thyroid hormones, testosterone and tryptophan hydroxylase in these interactions as well as their potential roles in liver regeneration. The association of these factors with inflammation and the modification of the mechanism of hepatic drug-metabolizing CYP isoform regulation are also presented because changes in the expression of CYP isoforms in the liver may result in subsequent changes to a marker substance used for testing CYP activity, thus providing a simple way to control the liver regeneration process or the dangerous stimulation of hepatocarcinogenesis.
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Sánchez-Ocampo EM, Azuela GE, Shibayama Salas M, Galar-Martínez M, Gómez-Oliván LM. Alterations in viability and CYP1A1 expression in SH SY5Y cell line by pollutants present in Madín Dam, Mexico. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 719:137500. [PMID: 32120108 DOI: 10.1016/j.scitotenv.2020.137500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/19/2020] [Accepted: 02/20/2020] [Indexed: 06/10/2023]
Abstract
Currently one of the problems facing global development is the availability of water. Although water is abundant the planet only a small portion is for human use and consumption. The problem is exacerbated due to different factors, mainly: meteorological phenomena, the presence of contaminants in the water and the increase in the number of inhabitants. Potential effects of pollutants not only can affect freshwater biota but also can be implicated in cancer development and neurodegenerative diseases in humans. The study was conducted in the Madín Dam, a reservoir of economic importance for the geographical area in which it is located, as well as catering to the population of nearby areas, and is a place where recreational activities such as fishing and kayaking are carried out. The aim of this study was to identify the toxic effects that the pollutants present in the water of the Madín Dam can generate on a human cell line (SH SY5Y) evaluating the cell viability and the participation of the Aril Hydrocarbon Receptor (AhR) and Pregnane X receptor (PXR) through of the expression of the CYP1A1 and CYP3A4 (canonical genes). In one of the five sites analyzed, cell viability was up to 50%, in this site a decrease in the normal expression of CYP1A1 was observed (p < 0.05) and the CYP3A4 gene was not expressed in the cells SH SY5Y. These results show that the SH SY5Y cell line is a good biomarker for assessing the human toxicity of environmental pollutants and relating it to neurodegenerative diseases.
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Affiliation(s)
- Esmeralda Michelle Sánchez-Ocampo
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan, Colonia Residencial Colón, CP 50120 Toluca, Estado de México, Mexico
| | | | - Mineko Shibayama Salas
- Departamento de Infectómica y Patogénesis Molecular, CINVESTAV-IPN, Av. IPN 2508, C.P. 07360 CDMX, Mexico
| | - Marcela Galar-Martínez
- Laboratorio de Toxicología Acuática, Departamento de Farmacia, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Unidad Profesional Adolfo López Mateos, Av. Wilfrido Massieu s/n y cerrada Manuel Stampa, Col. Industrial Vallejo, Ciudad de México CP, 07700, Mexico
| | - Leobardo Manuel Gómez-Oliván
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan, Colonia Residencial Colón, CP 50120 Toluca, Estado de México, Mexico.
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Hejazian SM, Zununi Vahed S, Moghaddas Sani H, Nariman-Saleh-Fam Z, Bastami M, Hosseiniyan Khatibi SM, Ardalan M, Samadi N. Steroid-resistant nephrotic syndrome: pharmacogenetics and epigenetic points and views. Expert Rev Clin Pharmacol 2020; 13:147-156. [PMID: 31847609 DOI: 10.1080/17512433.2020.1702877] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Introduction: Glucocorticoids (GCs) are the first-line therapy for patients with nephrotic syndrome (NS), a common glomerular disease, that cause complete remission in most of the cases. In response to the treatment, NS patients are divided into glucocorticoid-sensitive and -resistant. This variation is due to the differences in pharmacokinetics and pharmacodynamics of GCs in each patient that affect the response to the treatment modality. Since the genetic variations in drug-metabolizing enzymes and transporter proteins significantly impact the pharmacokinetics, efficacy and safety of the applied medications, this review highlights the basic mechanisms of genetic variations involved in GCs metabolism in drug-resistant NS patients.Areas covered: This review explains the pharmacogenetic variations that influence the profile of GCs responses and their pharmacokinetics in NS patients. Moreover, the epigenetic variations including histone modifications and miRNA gene regulation that have an influence on GCs responses will review. A comprehensive literature search was performed using different keywords to the reviewed topics.Expert opinion: The accumulative data suggest the importance of pharmacogenetic studies to develop personalized therapies and increase the GCs responsiveness in these patients. It is imperative to know that genetic testing does not give absolute answers to all existing questions in steroid resistance.
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Affiliation(s)
- Seyede Mina Hejazian
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Hakimeh Moghaddas Sani
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Ziba Nariman-Saleh-Fam
- Women's Reproductive Health Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Milad Bastami
- Department of Medical Genetics, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | | | - Nasser Samadi
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Biochemistry, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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Wang D, Lu R, Rempala G, Sadee W. Ligand-Free Estrogen Receptor α (ESR1) as Master Regulator for the Expression of CYP3A4 and Other Cytochrome P450 Enzymes in the Human Liver. Mol Pharmacol 2019; 96:430-440. [PMID: 31399483 PMCID: PMC6724575 DOI: 10.1124/mol.119.116897] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 08/01/2019] [Indexed: 12/25/2022] Open
Abstract
Cytochrome P450 3A4 isoform (CYP3A4) transcription is controlled by hepatic transcription factors (TFs), but how TFs dynamically interact remains uncertain. We hypothesize that several TFs form a regulatory network with nonlinear, dynamic, and hierarchical interactions. To resolve complex interactions, we have applied a computational approach for estimating Sobol's sensitivity indices (SSI) under generalized linear models to existing liver RNA expression microarray data (GSE9588) and RNA-seq data from genotype-tissue expression (GTEx), generating robust importance ranking of TF effects and interactions. The SSI-based analysis identified TFs and interacting TF pairs, triplets, and quadruplets involved in CYP3A4 expression. In addition to known CYP3A4 TFs, estrogen receptor α (ESR1) emerges as key TF with the strongest main effect and as the most frequently included TF interacting partner. Model predictions were validated using small interfering RNA (siRNA)/short hairpin RNA (shRNA) gene knockdown and clustered regularly interspaced short palindromic repeats (CRISPR)-mediated transcriptional activation of ESR1 in biliary epithelial Huh7 cells and human hepatocytes in the absence of estrogen. Moreover, ESR1 and known CYP3A4 TFs mutually regulate each other. Detectable in both male and female hepatocytes without added estrogen, the results demonstrate a role for unliganded ESR1 in CYP3A4 expression consistent with unliganded ESR1 signaling reported in other cell types. Added estrogen further enhances ESR1 effects. We propose a hierarchical regulatory network for CYP3A4 expression directed by ESR1 through self-regulation, cross regulation, and TF-TF interactions. We also demonstrate that ESR1 regulates the expression of other P450 enzymes, suggesting broad influence of ESR1 on xenobiotics metabolism in human liver. Further studies are required to understand the mechanisms underlying role of ESR1 in P450 regulation. SIGNIFICANCE STATEMENT: This study focuses on identifying key transcription factors and regulatory networks for CYP3A4, the main drug metabolizing enzymes in liver. We applied a new computational approach (Sobol's sensitivity analysis) to existing hepatic gene expression data to determine the role of transcription factors in regulating CYP3A4 expression, and used molecular genetics methods (siRNA/shRNA gene knockdown and CRISPR-mediated transcriptional activation) to test these interactions in life cells. This approach reveals a robust network of TFs, including their putative interactions and the relative impact of each interaction. We find that ESR1 serves as a key transcription factor function in regulating CYP3A4, and it appears to be acting at least in part in a ligand-free fashion.
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Affiliation(s)
- Danxin Wang
- Department of Pharmacotherapy and Translational Research, Center for Pharmacogenomics, College of Pharmacy, University of Florida, Gainesville, Florida (D.W.); Department of Clinical Sciences, Bioinformatics Core Facility, University of Texas Southwestern Medical Center, Dallas, Texas (R.L.); and Mathematical Bioscience Institute, (G.R.) and Center for Pharmacogenomics, Department of Cancer Biology and Genetics, College of Medicine (W.S.), Ohio State University, Columbus, Ohio
| | - Rong Lu
- Department of Pharmacotherapy and Translational Research, Center for Pharmacogenomics, College of Pharmacy, University of Florida, Gainesville, Florida (D.W.); Department of Clinical Sciences, Bioinformatics Core Facility, University of Texas Southwestern Medical Center, Dallas, Texas (R.L.); and Mathematical Bioscience Institute, (G.R.) and Center for Pharmacogenomics, Department of Cancer Biology and Genetics, College of Medicine (W.S.), Ohio State University, Columbus, Ohio
| | - Grzegorz Rempala
- Department of Pharmacotherapy and Translational Research, Center for Pharmacogenomics, College of Pharmacy, University of Florida, Gainesville, Florida (D.W.); Department of Clinical Sciences, Bioinformatics Core Facility, University of Texas Southwestern Medical Center, Dallas, Texas (R.L.); and Mathematical Bioscience Institute, (G.R.) and Center for Pharmacogenomics, Department of Cancer Biology and Genetics, College of Medicine (W.S.), Ohio State University, Columbus, Ohio
| | - Wolfgang Sadee
- Department of Pharmacotherapy and Translational Research, Center for Pharmacogenomics, College of Pharmacy, University of Florida, Gainesville, Florida (D.W.); Department of Clinical Sciences, Bioinformatics Core Facility, University of Texas Southwestern Medical Center, Dallas, Texas (R.L.); and Mathematical Bioscience Institute, (G.R.) and Center for Pharmacogenomics, Department of Cancer Biology and Genetics, College of Medicine (W.S.), Ohio State University, Columbus, Ohio
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11
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Charni-Natan M, Aloni-Grinstein R, Osher E, Rotter V. Liver and Steroid Hormones-Can a Touch of p53 Make a Difference? Front Endocrinol (Lausanne) 2019; 10:374. [PMID: 31244779 PMCID: PMC6581675 DOI: 10.3389/fendo.2019.00374] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 05/28/2019] [Indexed: 12/12/2022] Open
Abstract
The liver is the main metabolic organ in the body, serving as a significant hormonal secretory gland and functioning to maintain hormone balance and homeostasis. Steroid hormones regulate various biological pathways, mainly in the reproductive system and in many metabolic processes. The liver, as well as steroid hormones, contribute significantly, through functional intertwine, to homeostasis maintenance, and proper responses during stress. Malfunction of either has a significant impact on the other and may lead to severe liver diseases as well as to several endocrine syndromes. Thus, the regulation on liver functions as on steroid hormones levels and activities is well-controlled. p53, the well-known tumor suppressor gene, was recently found to regulate metabolism and general homeostasis processes, particularly within the liver. Moreover, p53 was shown to be involved in steroid hormones regulation. In this review, we discuss the bi-directional regulation of the liver and the steroid hormones pointing to p53 as a novel regulator in this axis. A comprehensive understanding of the molecular mechanisms of this axis may help to prevent and treat related disease, especially with the increasing exposure of the population to environmental steroid hormones and steroid hormone-based medication.
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Affiliation(s)
- Meital Charni-Natan
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Ronit Aloni-Grinstein
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Etty Osher
- Sackler Faculty of Medicine, Tel Aviv-Sourasky Medical Center, Institute of Endocrinology Metabolism and Hypertension, Tel Aviv University, Tel Aviv, Israel
| | - Varda Rotter
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
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12
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Belderbos BPS, Hussaarts KGAM, van Harten LJ, Oomen-de Hoop E, de Bruijn P, Hamberg P, van Alphen RJ, Haberkorn BCM, Lolkema MP, de Wit R, van Soest RJ, Mathijssen RHJ. Effects of prednisone on docetaxel pharmacokinetics in men with metastatic prostate cancer: A randomized drug-drug interaction study. Br J Clin Pharmacol 2019; 85:986-992. [PMID: 30737835 DOI: 10.1111/bcp.13889] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 02/04/2019] [Accepted: 02/04/2019] [Indexed: 12/24/2022] Open
Abstract
AIMS Docetaxel has been approved for the treatment of metastatic prostate cancer in combination with prednisone. Since prednisone is known to induce the cytochrome P450 iso-enzyme CYP3A4, which is the main metabolizing enzyme of docetaxel in the liver, a potential drug-drug interaction may occur. In this prospective randomized pharmacokinetic cross-over study we investigated docetaxel exposure with concomitant prednisone, compared to docetaxel monotherapy in men with metastatic prostate cancer. METHODS Patients scheduled to receive at least 6 cycles of docetaxel (75 mg/m2 ) and who gave written informed consent were randomized to receive either the 1st 3 cycles, or the last 3 consecutive cycles with prednisone (twice daily 5 mg). Pharmacokinetic blood sampling was performed during cycle 3 and cycle 6. Primary endpoint was difference in docetaxel exposure, calculated as area under the curve (AUC0-inf ) and analysed by means of a linear mixed model. Given the cross-over design the study was powered on 18 patients to answer the primary, pharmacokinetic, endpoint. RESULTS Eighteen evaluable patients were included in the trial. Docetaxel concentration with concomitant prednisone (AUC0-inf 2784 ng*h/mL, 95% confidence interval 2436-3183 ng*h/mL) was similar to the concentration of docetaxel monotherapy (AUC0-inf 2647 ng*h/mL, 95% confidence interval 2377-2949 ng*h/mL). Exploratory analysis showed no toxicity differences between docetaxel monotherapy and docetaxel cycles with prednisone. CONCLUSION No significant difference in docetaxel concentrations was observed. In addition, we found similar toxicity profiles in absence and presence of prednisone. Therefore, from a pharmacokinetic point of view, docetaxel may be administrated with or without prednisone.
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Affiliation(s)
- Bodine P S Belderbos
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Koen G A M Hussaarts
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Leonie J van Harten
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Esther Oomen-de Hoop
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Peter de Bruijn
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Paul Hamberg
- Department of Internal Medicine, Franciscus Gasthuis & Vlietland, Rotterdam, The Netherlands
| | - Robbert J van Alphen
- Department of Internal Medicine, Elisabeth Twee Steden Ziekenhuis, Tilburg, The Netherlands
| | | | - Martijn P Lolkema
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Ronald de Wit
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Robert J van Soest
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Ron H J Mathijssen
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
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Yamato M, Wada K, Hayashi T, Fujimoto M, Hosomi K, Oita A, Takada M. Association between Serum Amiodarone and N-Desethylamiodarone Concentrations and Development of Thyroid Dysfunction. Clin Drug Investig 2017; 38:39-48. [DOI: 10.1007/s40261-017-0582-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Amiodarone-induced thyroid dysfunction and a perturbed N-desethyl-amiodarone to amiodarone ratio: could a drug-induced toxicity be regulating exposure to the offending agent? Eur J Clin Pharmacol 2017; 73:1051-1052. [DOI: 10.1007/s00228-017-2261-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 04/25/2017] [Indexed: 10/19/2022]
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Response: Amiodarone-induced thyroid dysfunction and a perturbed N-desethyl-amiodarone to amiodarone ratio; could a drug-induced toxicity be regulating exposure to the offending agent? Eur J Clin Pharmacol 2017; 73:1053-1054. [DOI: 10.1007/s00228-017-2262-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 04/25/2017] [Indexed: 10/19/2022]
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Ligand-dependent and -independent regulation of human hepatic sphingomyelin phosphodiesterase acid-like 3A expression by pregnane X receptor and crosstalk with liver X receptor. Biochem Pharmacol 2017; 136:122-135. [DOI: 10.1016/j.bcp.2017.04.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 04/12/2017] [Indexed: 11/18/2022]
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Haffez H, Chisholm DR, Valentine R, Pohl E, Redfern C, Whiting A. The molecular basis of the interactions between synthetic retinoic acid analogues and the retinoic acid receptors. MEDCHEMCOMM 2017; 8:578-592. [PMID: 30108774 DOI: 10.1039/c6md00680a] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 01/17/2017] [Indexed: 01/17/2023]
Abstract
All-trans-retinoic acid (ATRA) and its synthetic analogues EC23 and EC19 direct cellular differentiation by interacting as ligands for the retinoic acid receptor (RARα, β and γ) family of nuclear receptor proteins. To date, a number of crystal structures of natural and synthetic ligands complexed to their target proteins have been solved, providing molecular level snap-shots of ligand binding. However, a deeper understanding of receptor and ligand flexibility and conformational freedom is required to develop stable and effective ATRA analogues for clinical use. Therefore, we have used molecular modelling techniques to define RAR interactions with ATRA and two synthetic analogues, EC19 and EC23, and compared their predicted biochemical activities to experimental measurements of relative ligand affinity and recruitment of coactivator proteins. A comprehensive molecular docking approach that explored the conformational space of the ligands indicated that ATRA is able to bind the three RAR proteins in a number of conformations with one extended structure being favoured. In contrast the biologically-distinct isomer, 9-cis-retinoic acid (; 9CRA), showed significantly less conformational flexibility in the RAR binding pockets. These findings were used to inform docking studies of the synthetic retinoids EC23 and EC19, and their respective methyl esters. EC23 was found to be an excellent mimic for ATRA, and occupied similar binding modes to ATRA in all three target RAR proteins. In comparison, EC19 exhibited an alternative binding mode which reduces the strength of key polar interactions in RARα/γ but is well-suited to the larger RARβ binding pocket. In contrast, docking of the corresponding esters revealed the loss of key polar interactions which may explain the much reduced biological activity. Our computational results were complemented using an in vitro binding assay based on FRET measurements, which showed that EC23 was a strongly binding, pan-agonist of the RARs, while EC19 exhibited specificity for RARβ, as predicted by the docking studies. These findings can account for the distinct behaviour of EC23 and EC19 in cellular differentiation assays, and additionally, the methods described herein can be further applied to the understanding of the molecular basis for the selectivity of different retinoids to RARα, β and γ.
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Affiliation(s)
- Hesham Haffez
- Department of Chemistry Durham University , South Road , Durham , DH1 3LE , UK . .,Department of Biosciences & Biophysical Sciences , Institute Durham University , South Road , Durham DH1 3LE , UK.,Northern Institute for Cancer Research , Medical School , Newcastle University , Newcastle upon Tyne , NE2 4HH , UK.,Department of Biochemistry and Molecular Biology , Pharmacy College , Helwan University , Cairo , Egypt
| | - David R Chisholm
- Department of Chemistry Durham University , South Road , Durham , DH1 3LE , UK .
| | - Roy Valentine
- High Force Research Ltd. , Bowburn North Industrial Estate , Bowburn , Durham , DH6 5PF , UK
| | - Ehmke Pohl
- Department of Biosciences & Biophysical Sciences , Institute Durham University , South Road , Durham DH1 3LE , UK
| | - Christopher Redfern
- Northern Institute for Cancer Research , Medical School , Newcastle University , Newcastle upon Tyne , NE2 4HH , UK
| | - Andrew Whiting
- Department of Chemistry Durham University , South Road , Durham , DH1 3LE , UK .
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Zhao G, Liu M, Wu X, Li G, Qiu F, Gu J, Zhao L. Effect of polymorphisms in CYP3A4, PPARA, NR1I2, NFKB1, ABCG2 and SLCO1B1 on the pharmacokinetics of lovastatin in healthy Chinese volunteers. Pharmacogenomics 2016; 18:65-75. [PMID: 27967318 DOI: 10.2217/pgs.16.31] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
AIM This study examined whether gene polymorphisms (CYP3A4, ABCG2, SLCO1B1, NR1I2, PPARA and NFKB1) influenced the pharmacokinetics of lovastatin in Chinese healthy subjects. PATIENTS & METHOD Plasma concentrations of lovastatin and lovastatin acid were quantified using LC/MS/MS. RESULTS PPARA c.208+3819 G allele carriers had approximately twofold higher AUC0-∞ and Cmax of lovastatin than wild-type (PPARA c.208+3819 AA) subjects. After adjustment for the PPARA variants, subjects with the SLCO1B1 521TT genotype had approximately 50% lower AUC0-∞ of lovastatin acid than those with 521TC/CC genotypes, while the AUC0-∞ of lovastatin lactone in NFKB1-94 DD wild-type carriers was twofold higher than in mutant homozygotes carriers. CONCLUSION Gene polymorphisms of PPARA, SLCO1B1 and NFKB1 affected the pharmacokinetics of lovastatin.
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Affiliation(s)
- Guilian Zhao
- Department of Pharmacy, Shengjing Hospital of China Medical University, No. 36 Sanhao Street Heping District, Shenyang 110004, China.,Department of Pharmacology, Shenyang Pharmaceutical University, No. 103 Wenhua Road Shenhe District, Shenyang 110016, China
| | - Mei Liu
- Department of Pharmacy, Shengjing Hospital of China Medical University, No. 36 Sanhao Street Heping District, Shenyang 110004, China.,Department of Clinical Pharmacy, Shenyang Pharmaceutical University, No. 103 Wenhua Road Shenhe District, Shenyang 110016, China
| | - Xiujun Wu
- Laboratory of Clinical Pharmacokinetics of TCM, Affiliated Hospital of Liaoning University of Traditional Chinese Medicine, No. 33 Beiling Street Huanggu District, Shenyang 110032, China
| | - Guofei Li
- Department of Pharmacy, Shengjing Hospital of China Medical University, No. 36 Sanhao Street Heping District, Shenyang 110004, China
| | - Feng Qiu
- Department of Pharmacy, Shengjing Hospital of China Medical University, No. 36 Sanhao Street Heping District, Shenyang 110004, China
| | - Jingkai Gu
- Research Center for Drug Metabolism, College of Life Science, Jilin University, No. 2699 Qianjin Street Chaoyang District, Changchun 130021, China
| | - Limei Zhao
- Department of Pharmacy, Shengjing Hospital of China Medical University, No. 36 Sanhao Street Heping District, Shenyang 110004, China
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de Wit D, Schneider TC, Moes DJAR, Roozen CFM, den Hartigh J, Gelderblom H, Guchelaar HJ, van der Hoeven JJ, Links TP, Kapiteijn E, van Erp NP. Everolimus pharmacokinetics and its exposure-toxicity relationship in patients with thyroid cancer. Cancer Chemother Pharmacol 2016; 78:63-71. [PMID: 27169792 PMCID: PMC4921118 DOI: 10.1007/s00280-016-3050-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 04/27/2016] [Indexed: 12/16/2022]
Abstract
Background Everolimus is a mTOR inhibitor used for the treatment of different solid malignancies. Many patients treated with the registered fixed 10 mg dose once daily are in need of dose interruptions, reductions or treatment discontinuation due to severe adverse events. This study determined the correlation between systemic everolimus exposure and toxicity. Additionally, the effect of different covariates on everolimus pharmacokinetics (PK) was explored. Methods Forty-two patients with advanced thyroid carcinoma were treated with 10 mg everolimus once daily. Serial pharmacokinetic sampling was performed on days 1 and 15. Subsequently, a population PK model was developed using NONMEM to estimate individual PK values used for analysis of an exposure–toxicity relationship. Furthermore, this model was used to investigate the influence of patient characteristics and genetic polymorphisms in genes coding for enzymes relevant in everolimus PK. Results Patients who required a dose reduction (n = 18) due to toxicity at any time during treatment had significant higher everolimus exposures [mean AUC0–24 (SD) 600 (274) vs. 395 (129) µg h/L, P = 0.008] than patients without a dose reduction (n = 22). A significant association between everolimus exposure and stomatitis was found in the four-level ordered logistic regression analysis (P = 0.047). The presence of at least one TTT haplotype in the ABCB1 gene was associated with a 21 % decrease in everolimus exposure. Conclusion The current study showed that dose reductions and everolimus-induced stomatitis were strongly associated with systemic everolimus drug exposure in patients with cancer. Our findings confirm observations from another study in patients with cancer and show us that everolimus is a good candidate for individualized dosing in patients with cancer. ClinicalTrial.gov number NCT01118065. Electronic supplementary material The online version of this article (doi:10.1007/s00280-016-3050-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- D de Wit
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands
| | - T C Schneider
- Department of Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - D J A R Moes
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands
| | - C F M Roozen
- Department of Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - J den Hartigh
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands
| | - H Gelderblom
- Department of Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - H J Guchelaar
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands
| | - J J van der Hoeven
- Department of Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - T P Links
- Department of Endocrinology, University Medical Center Groningen, Groningen, The Netherlands
| | - E Kapiteijn
- Department of Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - N P van Erp
- Department of Clinical Pharmacy, Radboud University Medical Center, Postbus 9101, 6500 HB, Nijmegen, The Netherlands.
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Liu W, Ning R, Chen RN, Hu JH, Gui HY, Wang YW, Liu J, Hu G, Yang J, Guo QL. Gambogic acid suppresses cytochrome P450 3A4 by downregulating pregnane X receptor and up-regulating DEC1 in human hepatoma HepG2 cells. Toxicol Res (Camb) 2015. [DOI: 10.1039/c4tx00239c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Gambogic acid suppresses cytochrome P450 3A4 by downregulating pregnane X receptor and up-regulating DEC1 in human hepatoma HepG2 cells.
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Affiliation(s)
- Wei Liu
- Department of Pharmacology
- Nanjing Medical University
- Nanjing
- China
| | - Rui Ning
- Department of Pharmacology
- Nanjing Medical University
- Nanjing
- China
| | - Rui-Ni Chen
- Department of Pharmacology
- Nanjing Medical University
- Nanjing
- China
| | - Jin-Hua Hu
- Department of Pharmacology
- Nanjing Medical University
- Nanjing
- China
| | - Hai-Yan Gui
- Maternity and Child Care Center of Xinyu
- Jiangxi
- China
| | - Yu-Wen Wang
- Department of Pharmacology
- Nanjing Medical University
- Nanjing
- China
| | - Jie Liu
- Department of Pharmacology
- Nanjing Medical University
- Nanjing
- China
| | - Gang Hu
- Department of Pharmacology
- Nanjing Medical University
- Nanjing
- China
| | - Jian Yang
- Department of Pharmacology
- Nanjing Medical University
- Nanjing
- China
| | - Qing-Long Guo
- Jiangsu Key Laboratory of Carcinogenesis and Intervention
- China Pharmaceutical University
- Nanjing 210009
- China
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Schoeppler KE, Aquilante CL, Kiser TH, Fish DN, Zamora MR. The impact of genetic polymorphisms, diltiazem, and demographic variables on everolimus trough concentrations in lung transplant recipients. Clin Transplant 2014; 28:590-7. [PMID: 24628014 DOI: 10.1111/ctr.12350] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2014] [Indexed: 01/07/2023]
Abstract
Everolimus (EVR) has inter-individual pharmacokinetic (PK) variability and a narrow therapeutic index. The study objective was to determine whether genetic polymorphisms, co-medications, and/or demographic variables accounted for inter-individual variability in EVR PK in lung transplant recipients (LTxR). LTxR were genotyped for ABCB1 c.1236C>T, ABCB1 c.2677G>T/A, ABCB1 c.3435C>T, CYP3A4*1B, CYP3A5*3, CYP2C8*2/*3/*4, and pregnane X receptor (NR1I2) c.44477T>C, c.63396C>T, c.69789A>G polymorphisms. The primary outcome was the difference in dose-adjusted EVR levels (EVR L/D) between ABCB1 diplotype groups (2 vs. 1 vs. 0 copies of the 1236C/2677G/3435C haplotype). Sixty-five LTxR were included. There was no significant difference in EVR L/D between ABCB1 CGC diplotype groups (CGC/CGC = 2.4 ± 1.1 [n = 9] vs. CGC/XXX = 2.5 ± 1.7 [n = 36] vs. XXX/XXX = 2.7 ± 1.7 ng/mL per mg/d [n = 20]; p = 0.9). CYP3A5*3, CYP3A4*1B, CYP2C8*3/*4, and NR1I2 polymorphisms were not associated with EVR L/D. EVR L/D was 3.4 ± 1.7 in LTxR receiving diltiazem (DILT) vs. 1.8 ± 1.1 ng/mL per mg/d in LTxR not receiving DILT (p <0.001). Demographic variables, including cystic fibrosis, were not associated with EVR PK. DILT use increased EVR L/D, but selected polymorphisms in ABCB1, CYP3A5, CYP3A4, CYP2C8, and NR1I2 did not affect EVR L/D in LTxR. Genotyping LTxR for these polymorphisms is unlikely to aid clinicians in optimizing EVR therapy.
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Affiliation(s)
- Kelly E Schoeppler
- Department of Pharmacy, University of Colorado Hospital, Aurora, CO, USA
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Kandel BA, Ekins S, Leuner K, Thasler WE, Harteneck C, Zanger UM. No Activation of Human Pregnane X Receptor by Hyperforin-Related Phloroglucinols. J Pharmacol Exp Ther 2013; 348:393-400. [DOI: 10.1124/jpet.113.209916] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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Bainy ACD, Kubota A, Goldstone JV, Lille-Langøy R, Karchner SI, Celander MC, Hahn ME, Goksøyr A, Stegeman JJ. Functional characterization of a full length pregnane X receptor, expression in vivo, and identification of PXR alleles, in zebrafish (Danio rerio). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2013; 142-143:447-57. [PMID: 24121122 PMCID: PMC3873750 DOI: 10.1016/j.aquatox.2013.09.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Revised: 09/06/2013] [Accepted: 09/12/2013] [Indexed: 05/25/2023]
Abstract
The pregnane X receptor (PXR) (nuclear receptor NR1I2) is a ligand activated transcription factor, mediating responses to diverse xenobiotic and endogenous chemicals. The properties of PXR in fish are not fully understood. Here we report on cloning and characterization of full-length PXR of zebrafish, Danio rerio, and pxr expression in vivo. Initial efforts gave a cDNA encoding a 430 amino acid protein identified as zebrafish pxr by phylogenetic and synteny analysis. The sequence of the cloned Pxr DNA binding domain (DBD) was highly conserved, with 74% identity to human PXR-DBD, while the ligand-binding domain (LBD) of the cloned sequence was only 44% identical to human PXR-LBD. Sequence variation among clones in the initial effort prompted sequencing of multiple clones from a single fish. There were two prominent variants, one sequence with S183, Y218 and H383 and the other with I183, C218 and N383, which we designate as alleles pxr*1 (nr1i2*1) and pxr*2 (nr1i2*2), respectively. In COS-7 cells co-transfected with a PXR-responsive reporter gene, the full-length Pxr*1 (the more common variant) was activated by known PXR agonists clotrimazole and pregnenolone 16α-carbonitrile but to a lesser extent than the full-length human PXR. Activation of full-length Pxr*1 was only 10% of that with the Pxr*1 LBD. Quantitative real time PCR analysis showed prominent expression of pxr in liver and eye, as well as brain and intestine of adult zebrafish. The pxr was expressed in heart and kidney at levels similar to that in intestine. The expression of pxr in liver was weakly induced by ligands for mammalian PXR or constitutive androstane receptor (NR1I3). The results establish a foundation for PXR studies in this vertebrate model. PXR allelic variation and the differences between the full-length PXR and the LBD in reporter assays have implications for assessing the action of PXR ligands in zebrafish.
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Affiliation(s)
- Afonso C D Bainy
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA; Departamento de Bioquímica, CCB, Universidade Federal de Santa Catarina, Florianópolis, SC 88040-900, Brazil
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Effects of decreased vitamin D and accumulated uremic toxin on human CYP3A4 activity in patients with end-stage renal disease. Toxins (Basel) 2013; 5:1475-85. [PMID: 23965431 PMCID: PMC3760047 DOI: 10.3390/toxins5081475] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 08/01/2013] [Accepted: 08/06/2013] [Indexed: 01/10/2023] Open
Abstract
In patients with end-stage renal disease, not only renal clearance but also hepatic clearance is known to be impaired. For instance, the concentration of erythromycin, a substrate of cytochrome P450 3A4 (CYP3A4), has been reported to be elevated in patients with end-stage renal disease. The purpose of this study is to elucidate the reason for the decrease in hepatic clearance in patients with end-stage renal disease. Deproteinized pooled sera were used to assess the effects of low-molecular-weight uremic toxins on CYP3A4 activity in human liver microsomes and human LS180 cells. Four uremic toxins (3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid, hippuric acid, indole-3-acetic acid, and 3-indoxyl sulfate) present at high concentrations in uremic serum were also studied. Simultaneous treatment of uremic serum (less than 10%) or uremic toxins did not affect testosterone 6β-hydroxylation in human liver microsomes. On the other hand, pretreatment of each serum activates CYP3A4 in LS180 cells, and the increased CYP3A4 activity in uremic serum-treated cells was smaller than normal serum-treated cells. In addition, CYP3A4 and CYP24A1 mRNA levels also increased in LS180 cells exposed to normal serum, and this effect was reduced in uremic serum-treated cells and in cells exposed to uremic serum added to normal serum. Furthermore, addition of 1,25-dihydroxyvitamin D to uremic serum partially restored the serum effect on CYP3A4 expression. The present study suggests that the decrease of 1,25-dihydroxyvitamin D and the accumulation of uremic toxins contributed to the decreased hepatic clearance of CYP3A4 substrates in patients with end-stage renal disease.
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Paul KB, Thompson JT, Simmons SO, Vanden Heuvel JP, Crofton KM. Evidence for triclosan-induced activation of human and rodent xenobiotic nuclear receptors. Toxicol In Vitro 2013; 27:2049-60. [PMID: 23899473 DOI: 10.1016/j.tiv.2013.07.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 06/05/2013] [Accepted: 07/19/2013] [Indexed: 10/26/2022]
Abstract
The bacteriostat triclosan (2,4,4'-trichloro-2'-hydroxydiphenylether) (TCS) decreases rat serum thyroxine via putative nuclear receptor (NR) interaction(s) and subsequent transcriptional up-regulation of hepatic catabolism and clearance. However, due to the evolutionary divergence of the constitutive androstane and pregnane-X receptors (CAR, PXR), TCS-mediated downstream effects may be species-dependent. To test the hypothesis that TCS activates xenobiotic NRs across species, cell-based NR reporter assays were employed to assess potential activation of rat, mouse, and human PXR, and rat, mouse, and three splice variants of human CAR. TCS activated hPXR, acted as an inverse agonist of hCAR1, and as a weak agonist of hCAR3. TCS failed to activate rPXR in full-length receptor reporter assays, and instead acted as a modest inverse agonist of rCAR. Consistent with the rat data, TCS also failed to activate mPXR and was a modest inverse agonist of mCAR. These data suggest that TCS may interact with multiple NRs, including hPXR, hCAR1, hCAR3, and rCAR in order to potentially affect hepatic catabolism. Overall these data support the conclusion that TCS may interact with NRs to regulate hepatic catabolism and downstream thyroid hormone homeostasis in both rat and human models, though perhaps by divergent mechanisms.
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Affiliation(s)
- Katie B Paul
- University of North Carolina at Chapel Hill, Curriculum in Toxicology, CB 7270, Chapel Hill, NC 27599, United States; Integrated Systems Toxicology Division, National Health and Environmental Effects Research Laboratory, United States
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Vavrova A, Vrzal R, Dvorak Z. A nonradioactive electrophoretic mobility shift assay for measurement of pregnane X receptor binding activity to CYP3A4 response element. Electrophoresis 2013; 34:1863-8. [DOI: 10.1002/elps.201300079] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Aneta Vavrova
- Department of Cell Biology and Genetic; Faculty of Science; Palacky University Olomouc; Slechtitelu; Olomouc; Czech Republic
| | - Radim Vrzal
- Department of Cell Biology and Genetic; Faculty of Science; Palacky University Olomouc; Slechtitelu; Olomouc; Czech Republic
| | - Zdenek Dvorak
- Department of Cell Biology and Genetic; Faculty of Science; Palacky University Olomouc; Slechtitelu; Olomouc; Czech Republic
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Sivertsson L, Edebert I, Palmertz MP, Ingelman-Sundberg M, Neve EPA. Induced CYP3A4 expression in confluent Huh7 hepatoma cells as a result of decreased cell proliferation and subsequent pregnane X receptor activation. Mol Pharmacol 2012; 83:659-70. [PMID: 23264496 DOI: 10.1124/mol.112.082305] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
We have previously shown that confluent growth of the human hepatoma cell line Huh7 substantially induces the CYP3A4 mRNA, protein, and activity levels. Here, the mechanisms behind were investigated, and a transcriptome analysis revealed significant up-regulation of liver-specific functions, whereas pathways related to proliferation and cell cycle were down-regulated in the confluent cells. Reporter analysis revealed that the CYP3A4 gene was transcriptionally activated during confluence in a process involving pregnane X receptor (PXR). PXR expression was increased, and PXR protein accumulated in the nuclei during confluent growth. The PXR ligand rifampicin further increased the expression of CYP3A4, and siRNA-mediated knock-down of PXR in confluent cells resulted in decreased CYP3A4 expression. Cyclin-dependent kinase 2 (CDK2), a known modulator of the cell cycle and a negative regulator of PXR, was more highly expressed in proliferating control cells. Trypsinization of the confluent cells and replating them subconfluent resulted in a decrease in CYP3A4 and PXR expression back to levels observed in subconfluent control cells, whereas the CDK2 levels increased. Knock-down of CDK2 in proliferating control cells increased the CYP3A4 and PXR protein levels. Moreover, the CDK inhibitor roscovitine stimulated the expression of CYP3A4. A phosphorylation-deficient mutation (S350A) in the PXR protein significantly induced the CYP3A4 transcription. In conclusion, the data strongly suggest that the increased CYP3A4 expression in confluent Huh7 cells is caused by the endogenous induction of PXR as a result of cell-cell contact inhibited proliferation and subsequent decreased CDK2 activities, indicating an endogenous, non-ligand-dependent regulation of PXR and CYP3A4, possibly of physiologic and pharmacological significance.
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Affiliation(s)
- Louise Sivertsson
- Karolinska Institutet, Department of Physiology and Pharmacology, Nanna Svartz v. 2, SE-171 77 Stockholm, Sweden.
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Moes DJA, Press RR, den Hartigh J, van der Straaten T, de Fijter JW, Guchelaar HJ. Population Pharmacokinetics and Pharmacogenetics of Everolimus in Renal Transplant Patients. Clin Pharmacokinet 2012; 51:467-80. [DOI: 10.2165/11599710-000000000-00000] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Park YJ, Lee EK, Lee YK, Park DJ, Jang HC, Moore DD. Opposing regulation of cytochrome P450 expression by CAR and PXR in hypothyroid mice. Toxicol Appl Pharmacol 2012; 263:131-7. [PMID: 22503787 DOI: 10.1016/j.taap.2012.03.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 03/08/2012] [Accepted: 03/27/2012] [Indexed: 12/20/2022]
Abstract
Clinical hypothyroidism affects various metabolic processes including drug metabolism. CYP2B and CYP3A are important cytochrome P450 drug metabolizing enzymes that are regulated by the xenobiotic receptors constitutive androstane receptor (CAR, NR1I3) and pregnane X receptor (PXR, NR1I2). We evaluated the regulation of the hepatic expression of CYPs by CAR and PXR in the hypothyroid state induced by a low-iodine diet containing 0.15% propylthiouracil. Expression of Cyp3a11 was suppressed in hypothyroid C57BL/6 wild type (WT) mice and a further decrement was observed in hypothyroid CAR-/- mice, but not in hypothyroid PXR-/- mice. In contrast, expression of Cyp2b10 was induced in both WT and PXR-/- hypothyroid mice, and this induction was abolished in CAR-/- mice and in and CAR-/- PXR-/- double knockouts. CAR mRNA expression was increased by hypothyroidism, while PXR expression remained unchanged. Carbamazepine (CBZ) is a commonly used antiepileptic that is metabolized by CYP3A isoforms. After CBZ treatment of normal chow fed mice, serum CBZ levels were highest in CAR-/- mice and lowest in WT and PXR-/- mice. Hypothyroid WT or PXR-/- mice survived chronic CBZ treatment, but all hypothyroid CAR-/- and CAR-/- PXR-/- mice died, with CAR-/-PXR-/- mice surviving longer than CAR-/- mice (12.3±3.3 days vs. 6.3±2.1 days, p=0.04). All these findings suggest that hypothyroid status affects xenobiotic metabolism, with opposing responses of CAR and PXR and their CYP targets that can cancel each other out, decreasing serious metabolic derangement in response to a xenobiotic challenge.
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Affiliation(s)
- Young Joo Park
- Department of Internal Medicine, Seoul National University College of Medicine, Republic of Korea
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Berthier A, Oger F, Gheeraert C, Boulahtouf A, Le Guével R, Balaguer P, Staels B, Salbert G, Lefebvre P. The novel antibacterial compound walrycin A induces human PXR transcriptional activity. Toxicol Sci 2012; 127:225-35. [PMID: 22314385 DOI: 10.1093/toxsci/kfs073] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The human pregnane X receptor (PXR) is a ligand-regulated transcription factor belonging to the nuclear receptor superfamily. PXR is activated by a large, structurally diverse, set of endogenous and xenobiotic compounds and coordinates the expression of genes central to metabolism and excretion of potentially harmful chemicals and therapeutic drugs in humans. Walrycin A is a novel antibacterial compound targeting the WalK/WalR two-component signal transduction system of Gram (+) bacteria. Here, we report that, in hepatoma cells, walrycin A potently activates a gene set known to be regulated by the xenobiotic sensor PXR. Walrycin A was as efficient as the reference PXR agonist rifampicin to activate PXR in a transactivation assay at noncytotoxic concentrations. Using a limited proteolysis assay, we show that walrycin A induces conformational changes at a concentration which correlates with walrycin A ability to enhance the expression of prototypic target genes, suggesting that walrycin A interacts with PXR. The activation of the canonical human PXR target gene CYP3A4 by walrycin A is dose and PXR dependent. Finally, in silico docking experiments suggest that the walrycin A oxidation product Russig's blue is the actual ligand for PXR. Taken together, these results identify walrycin A as a novel human PXR activator.
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Cheng J, Ma X, Gonzalez FJ. Pregnane X receptor- and CYP3A4-humanized mouse models and their applications. Br J Pharmacol 2011; 163:461-8. [PMID: 21091656 DOI: 10.1111/j.1476-5381.2010.01129.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Pregnane X receptor (PXR) is a pivotal nuclear receptor modulating xenobiotic metabolism primarily through its regulation of CYP3A4, the most important enzyme involved in drug metabolism in humans. Due to the marked species differences in ligand recognition by PXR, PXR-humanized (hPXR) mice, and mice expressing human PXR and CYP3A4 (Tg3A4/hPXR) were established. hPXR and Tg3A4/hPXR mice are valuable models for investigating the role of PXR in xenobiotic metabolism and toxicity, in lipid, bile acid and steroid hormone homeostasis, and in the control of inflammation.
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Affiliation(s)
- Jie Cheng
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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Liu YH, Mo SL, Bi HC, Hu BF, Li CG, Wang YT, Huang L, Huang M, Duan W, Liu JP, Wei MQ, Zhou SF. Regulation of human pregnane X receptor and its target gene cytochrome P450 3A4 by Chinese herbal compounds and a molecular docking study. Xenobiotica 2010; 41:259-80. [PMID: 21117944 DOI: 10.3109/00498254.2010.537395] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The pregnane X receptor (PXR) plays a critical role in the regulation of human cytochrome P450 3A4 (CYP3A4) gene. In this study, we investigated the effect of an array of compounds isolated from Chinese herbal medicines on the activity of PXR using a luciferase reporter gene assay in transiently transfected HepG2 and Huh7 cells and on the expression of PXR and CYP3A4 in LS174T cells. Furthermore, molecular docking was performed to investigate the binding modes of herbal compounds with PXR. Praeruptorin A and C, salvianolic acid B, sodium danshensu, protocatechuic aldehyde, cryptotanshinone, emodin, morin, and tanshinone IIA significantly transactivated the CYP3A4 reporter gene construct in either HepG2 or Huh7 cells. The PXR mRNA expression in LS174T cells was significantly induced by physcion, protocatechuic aldehyde, salvianolic acid B, and sodium danshensu. However, epifriedelanol, morin, praeruptorin D, mulberroside A, tanshinone I, and tanshinone IIA significantly down-regulated the expression of PXR mRNA in LS174T cells. All the herbal compounds tested can be readily docked into the ligand-binding cavity of PXR mainly through hydrogen bond and aromatic interactions with Ser247, Gln285, His407, and Arg401. These findings suggest that herbal medicines can significantly regulate PXR and CYP3A4 and this has important implication in herb-drug interactions.
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Affiliation(s)
- Ya-He Liu
- School of Health Sciences & Health Innovations Research Institute, RMIT University, Bundoora, Victoria, Australia
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Fery Y, Mueller SO, Schrenk D. Development of stably transfected human and rat hepatoma cell lines for the species-specific assessment of xenobiotic response enhancer module (XREM)-dependent induction of drug metabolism. Toxicology 2010; 277:11-9. [PMID: 20832446 DOI: 10.1016/j.tox.2010.08.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 08/11/2010] [Accepted: 08/13/2010] [Indexed: 11/15/2022]
Abstract
Based on our current knowledge, PXR holds a key position in the induction of a selective battery of enzymes and transporters of drug metabolism. In order to prevent serious adverse drug effects or unpredicted drug-drug interactions (DDI), it is compulsory to investigate the possible inducing potency of drugs under development. Furthermore, analysis of the inducing potency of environmental pollutants and new or manufactured chemicals is part of toxicological risk assessment. In non-transfected human HepG2 and rat H4IIE hepatoma cells, we examined the characteristics of expression of 45 genes involved in drug metabolism. A few gene products such as CYP2B6 or CYP3A4 mRNA were prominent in HepG2 cells while their major rat counterparts were, e.g., CYP2B3 or CYP3A1/3A3. Furthermore, a number of xenobiotic receptors including PXR were expressed in both cell lines. A number of genes were regulated in a cell type and species-specific manner after incubation with the prototypical PXR agonists rifampicin or dexamethasone, respectively. Then, we established cell-based reporter gene assays for screening for PXR-dependent induction of drug metabolism. HepG2 and H4IIE cells were stably transfected with a reporter gene containing PXR responsive elements (XREMs) which mediate the induction of PXR target genes such as CYP3A enzymes. With both stable cell lines the CYP inducers clotrimazole, dexamethasone, omeprazole, phenobarbital, rifampicin, as well as the drug candidate EMD 392949 and the brominated flame retardants hexabromocylododecane (HBCD) and a pentabromodiphenyl ether (pentaBDE) mixture were screened. In the human HepG2-XREM3 and rat H4IIE-XREM3 cells, clotrimazole and HBCD were found as common activators of the human and rat PXR whereas pentaBDE was more effective with the human cell system. Omeprazole and phenobarbital did not induce the rat PXR-dependent reporter gene expression in H4IIE-XREM3 cells, while a moderate increase was found in HepG2-XREM3 cells. EMD 392949 also acted as inducer in human but not in rat cells confirming in vivo observations. In summary, the established PXR-dependent in vitro system allows the simultaneous, fast, and species-specific screening of chemicals, environmental contaminants, food ingredients and drugs for CYP3A induction in cells of human and rat origin.
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Affiliation(s)
- Yvonne Fery
- Food Chemistry and Toxicology, University of Kaiserslautern, Erwin-Schroedinger-Strasse 52, D-67663 Kaiserslautern, Germany
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