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Sharma S, Suresh Ahire D, Prasad B. Utility of Quantitative Proteomics for Enhancing the Predictive Ability of Physiologically Based Pharmacokinetic Models Across Disease States. J Clin Pharmacol 2020; 60 Suppl 1:S17-S35. [DOI: 10.1002/jcph.1709] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 07/09/2020] [Indexed: 12/13/2022]
Affiliation(s)
- Sheena Sharma
- Department of Pharmaceutical Sciences Washington State University Spokane Washington USA
| | - Deepak Suresh Ahire
- Department of Pharmaceutical Sciences Washington State University Spokane Washington USA
| | - Bhagwat Prasad
- Department of Pharmaceutical Sciences Washington State University Spokane Washington USA
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Li AP. In Vitro Human Cell–Based Experimental Models for the Evaluation of Enteric Metabolism and Drug Interaction Potential of Drugs and Natural Products. Drug Metab Dispos 2020; 48:980-992. [DOI: 10.1124/dmd.120.000053] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/18/2020] [Indexed: 12/14/2022] Open
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3
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El-Ghiaty MA, Shoieb SM, El-Kadi AOS. Cytochrome P450-mediated drug interactions in COVID-19 patients: Current findings and possible mechanisms. Med Hypotheses 2020; 144:110033. [PMID: 32758877 PMCID: PMC7318945 DOI: 10.1016/j.mehy.2020.110033] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 06/20/2020] [Indexed: 02/06/2023]
Abstract
At the end of 2019, the entire world has witnessed the birth of a new member of coronavirus family in Wuhan, China. Ever since, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has swiftly invaded every corner on the planet. By the end of April 2020, almost 3.5 million cases have been reported worldwide, with a death toll of about 250,000 deaths. It is currently well-recognized that patient’s immune response plays a pivotal role in the pathogenesis of Coronavirus Disease 2019 (COVID-19). This inflammatory element was evidenced by its elevated mediators that, in severe cases, reach their peak in a cytokine storm. Together with the reported markers of liver injury, such hyperinflammatory state may trigger significant derangements in hepatic cytochrome P450 metabolic machinery, and subsequent modulation of drug clearance that may result in unexpected therapeutic/toxic response. We hypothesize that COVID-19 patients are potentially vulnerable to a significant disease-drug interaction, and therefore, suitable dosing guidelines with therapeutic drug monitoring should be implemented to assure optimal clinical outcomes.
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Affiliation(s)
- Mahmoud A El-Ghiaty
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Sherif M Shoieb
- 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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Modulation of aryl hydrocarbon receptor-regulated enzymes by trimethylarsine oxide in C57BL/6 mice: In vivo and in vitro studies. Toxicol Lett 2015; 238:17-31. [PMID: 26144063 DOI: 10.1016/j.toxlet.2015.06.1646] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 06/19/2015] [Accepted: 06/28/2015] [Indexed: 01/10/2023]
Abstract
Arsenic is a worldwide environmental pollutant that is associated with skin and several types of internal cancers. Recent reports revealed that arsenic biomethylation could activate the toxic and carcinogenic potential of arsenic. Therefore, we investigated the effect of trimethylarsine oxide (TMAO) on the activation of AhR-regulated genes in vivo and in vitro. In vivo, C57BL/6 mice received TMAO (13mg/kg i.p.) with or without the prototypical AhR ligand, TCDD (15μg/kg), then the livers were harvested at 6 and 24h post-treatment. In vitro, isolated hepatocytes from C57BL/6 mice were treated with TMAO (5μM) in the absence and presence of TCDD (1nM) for 6 and 24h. Our in vivo results demonstrated that, TMAO alone increased Cyp1a1, Cyp1a2, Cyp1b1, Nqo1, Gsta1, and Ho-1 at mRNA level. Upon co-exposure to TMAO and TCDD, TMAO potentiated the TCDD-mediated induction of Cyp1a1, Cyp1b1, and Nqo1 mRNA levels. Western blotting revealed that, TMAO alone increased Cyp1a1, Cyp1a2, Nqo1, Gsta1/2, and Ho-1 protein levels, and potentiated the TCDD-mediated induction of Cyp1a1 and Cyp1b1 protein level. In addition, TMAO alone significantly increased Cyp1a1, Cyp1a2, Nqo1, Gst, and Ho-1 activities and significantly potentiated the TCDD-mediated induction of Cyp1a1 activity. At the in vitro level, TMAO induced Cyp1a1 and potentiated the TCDD-mediated induction of Cyp1a1 at mRNA, protein and activity levels. In addition, TMAO increased the nuclear localization of AhR and AhR-dependent XRE-driven luciferase activity. Our results demonstrate that the TMAO, modulates AhR-regulated genes which could potentially participate, at least in part, in arsenic induced toxicity and carcinogenicity.
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Anwar-Mohamed A, Abdelhamid G, Amara IEA, El-Kadi AOS. Differential modulation of cytochrome P450 1a1 by arsenite in vivo and in vitro in C57BL/6 mice. Free Radic Biol Med 2013; 58:52-63. [PMID: 23369756 DOI: 10.1016/j.freeradbiomed.2013.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 01/14/2013] [Accepted: 01/22/2013] [Indexed: 10/27/2022]
Abstract
Heavy metals, typified by arsenite (As(III)), have been implicated in altering the carcinogenicity of aryl hydrocarbon receptor (AhR) ligands, typified by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), by modulating the induction of the Cyp1a1 enzyme, but the mechanism remains unresolved. In this study, the effects of As(III) on Cyp1a1 expression and activity were investigated in C57BL/6 mouse livers and isolated hepatocytes. For this purpose, C57BL/6 mice were injected intraperitoneally with As(III) (12.5 mg/kg) in the absence and presence of TCDD (15 μg/kg) for 6 and 24 h. Furthermore, isolated hepatocytes from C57BL/6 mice were treated with As(III) (1, 5, and 10 μM) in the absence and presence of TCDD (1 nM) for 3, 6, 12, and 24 h. At the in vivo level, As(III) decreased the TCDD-mediated induction of Cyp1a1 mRNA at 6h while potentiating its mRNA, protein, and catalytic activity levels at 24 h. At the in vitro level, As(III) decreased the TCDD-mediated induction of Cyp1a1 mRNA in a concentration- and time-dependent manner. Moreover, As(III) decreased the TCDD-mediated induction of Cyp1a1 protein and catalytic activity levels at 24 h. Interestingly, As(III) increased the serum hemoglobin (Hb) levels in animals treated for 24 h. Upon treatment of isolated hepatocytes with Hb alone, there was an increase in the nuclear accumulation of AhR and AhR-dependent luciferase activity. Furthermore, Hb potentiated the TCDD-induced AhR-dependent luciferase activity. Importantly, when isolated hepatocytes were treated for 5h with As(III) in the presence of TCDD and the medium was then replaced with new medium containing Hb, there was potentiation of the TCDD-mediated effect. Taken together, these results demonstrate for the first time that there is a differential modulation of the TCDD-mediated induction of Cyp1a1 by As(III) in C57BL/6 mouse livers and isolated hepatocytes. Thus, this study implicates Hb as an in vivo-specific modulator.
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Affiliation(s)
- Anwar Anwar-Mohamed
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E1
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Abdelhamid G, Amara IEA, Anwar-Mohamed A, El-Kadi AOS. Modulation of cytochrome P450 1 (Cyp1) by vanadium in hepatic tissue and isolated hepatocyte of C57BL/6 mice. Arch Toxicol 2013; 87:1531-43. [DOI: 10.1007/s00204-013-1023-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 02/06/2013] [Indexed: 10/27/2022]
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7
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Amara IE, Anwar-Mohamed A, Abdelhamid G, El-Kadi AO. Mercury modulates the cytochrome P450 1a1, 1a2 and 1b1 in C57BL/6J mice: in vivo and in vitro studies. Toxicol Appl Pharmacol 2013; 266:419-29. [DOI: 10.1016/j.taap.2012.11.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 11/17/2012] [Accepted: 11/30/2012] [Indexed: 10/27/2022]
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Brocks DR, Hamdy DA, Ben-Eltriki M, Patel JP, El-Kadi AO. Effect of rat serum lipoproteins on mRNA levels and amiodarone metabolism by cultured primary rat hepatocytes. J Pharm Sci 2012; 102:262-70. [PMID: 23132435 DOI: 10.1002/jps.23348] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 10/02/2012] [Accepted: 10/04/2012] [Indexed: 01/12/2023]
Abstract
Hyperlipidemia can significantly increase amiodarone (AM) in vivo liver uptake and decrease its velocity of microsomal metabolism. Here, hepatocytes isolated from normolipidemic (NL) and hyperlipidemic rats were incubated with AM in the presence or absence of diluted NL or hyperlipidemic serum. The serum was added either as preincubation before drug, or concurrently with drug; incubations without rat serum were used as controls. The hepatocyte levels of mRNA for several proteins and enzymes were also measured. Disappearance of AM was seen up to 72 h. There was little difference between hepatocytes from NL or hyperlipidemic animals in intrinsic clearance (CL(int) ) of AM. The effect of hyperlipidemic rat serum, either before or with AM, was profound, causing a significant reduction in the CL(int) . Reductions were seen in mRNA for cytochrome P450 1A1, 3A2, and 2D1, some transporters, and low-density lipoprotein receptors after exposure of hepatocytes to lipoprotein-rich sera. In conclusion, exposure of isolated hepatocytes to hyperlipidemic serum caused decreases in AM CL(int) and lower mRNA levels for some proteins involved in the uptake and metabolism of AM. When coincubated with serum, an additional effect of increased binding to lipoproteins seemed to further contribute to a reduced CL of AM.
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Patel JP, Hamdy DA, El-kadi AO, Brocks DR. Effect of serum lipoproteins on stereoselective halofantrine metabolism by rat hepatocytes. Chirality 2012; 24:558-65. [DOI: 10.1002/chir.22054] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 03/19/2012] [Indexed: 11/06/2022]
Affiliation(s)
- Jigar P. Patel
- Faculty of Pharmacy; University of Montreal; Montreal Quebec Canada
| | | | - A. O. El-kadi
- Faculty of Pharmacy and Pharmaceutical Sciences; University of Alberta; Edmonton Alberta Canada
| | - Dion R. Brocks
- Faculty of Pharmacy and Pharmaceutical Sciences; University of Alberta; Edmonton Alberta Canada
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Anwar-Mohamed A, Klotz LO, El-Kadi AOS. Inhibition of Heme Oxygenase-1 Partially Reverses the Arsenite-Mediated Decrease of CYP1A1, CYP1A2, CYP3A23, and CYP3A2 Catalytic Activity in Isolated Rat Hepatocytes. Drug Metab Dispos 2011; 40:504-14. [DOI: 10.1124/dmd.111.042564] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Fradette C, Batonga J, Teng S, Piquette-Miller M, du Souich P. Animal models of acute moderate hypoxia are associated with a down-regulation of CYP1A1, 1A2, 2B4, 2C5, and 2C16 and up-regulation of CYP3A6 and P-glycoprotein in liver. Drug Metab Dispos 2007; 35:765-71. [PMID: 17303624 DOI: 10.1124/dmd.106.013508] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In humans, indirect evidence suggests that hypoxia reduces the rate of biotransformation of drugs cleared by cytochrome P450 (P450) subfamilies CYP1A, 2B, and 2C. The aim of this study was to assess whether acute moderate hypoxia modulates the expression of CYP2B4, 2C5, and 2C16 in vivo, and to determine whether the changes in hepatic P450 are conveyed by serum mediators. Moreover, because hypoxia increases the expression of P-glycoprotein in vitro, we examined whether in vivo acute moderate hypoxia modulates the expression of several membrane transporters in the liver. Rabbits and rats were exposed to a fractional concentration of oxygen of 8% for 48 h to generate a stable arterial partial pressure of O2 of 34 +/- 1 mm Hg. Compared with rabbits breathing room air, hypoxia in rabbits reduced the amount of CYP1A1, 1A2, 2B4, 2C5, and 2C16 proteins and increased the expression of CYP3A6. Sera of rabbits with hypoxia were fractionated by size exclusion chromatography, the fractions were tested for their ability to modify the expression of P450 isoforms, and serum mediators were identified through neutralization experiments. The serum mediators responsible for the down-regulation of P450 isoforms were interferon-gamma, interleukin-1beta (IL-1beta), and IL-2. In vivo, in rats, hypoxia increased the mRNA and protein expression of P-glycoprotein but did not affect the mRNA of breast cancer resistance protein and organic anion-transporting polypeptide 2. It is concluded that in vivo, hypoxia down-regulates rabbit hepatic CYP1A1, 1A2, 2B4, 2C5, and 2C16 and up-regulates CYP3A6. CYP3A11 and P-glycoprotein were up-regulated in the livers of hypoxic rats.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics
- ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism
- Acute Disease
- Animals
- Aryl Hydrocarbon Hydroxylases/genetics
- Aryl Hydrocarbon Hydroxylases/metabolism
- Cell Hypoxia
- Cells, Cultured
- Chromatography, High Pressure Liquid
- Cytochrome P-450 CYP1A1/genetics
- Cytochrome P-450 CYP1A1/metabolism
- Cytochrome P-450 CYP3A
- Down-Regulation/drug effects
- Hepatocytes/cytology
- Hepatocytes/drug effects
- Hepatocytes/metabolism
- Hypoxia/physiopathology
- Immunoblotting
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Liver/drug effects
- Liver/enzymology
- Liver/metabolism
- Male
- Models, Animal
- Oxygen/metabolism
- Oxygen/pharmacology
- Oxygen Consumption
- Pregnane X Receptor
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rabbits
- Receptors, Steroid/genetics
- Receptors, Steroid/metabolism
- Up-Regulation/drug effects
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Affiliation(s)
- Caroline Fradette
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada
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Taherzadeh M, Fradette C, Bleau AM, Jomphe C, Trudeau LE, du Souich P. The 21-aminosteroid U74389G prevents the down-regulation and decrease in activity of CYP1A1, 1A2 and 3A6 induced by an inflammatory reaction. Biochem Pharmacol 2006; 71:366-76. [PMID: 16332358 DOI: 10.1016/j.bcp.2005.10.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Revised: 10/21/2005] [Accepted: 10/21/2005] [Indexed: 11/16/2022]
Abstract
In vivo, the 21-aminosteroid U74389G prevents the decrease in cytochrome P450 (P450) activity produced by a turpentine-induced inflammatory reaction (TIIR). To investigate the underlying mechanism of action, four groups of rabbits were used, controls receiving or not U74389G, and rabbits with the inflammatory reaction receiving or not U74389G. Hepatocytes were isolated 48h later and incubated for 4 and 24h with the serum of the rabbits. In vivo, the TIIR diminished CYP1A1/2 and 3A6 expression, and enhanced hepatic malondialdehyde (MDA) and nitric oxide (NO*) concentrations (p<0.05). U74389G prevented the increase in MDA, as well as the decrease in CYP1A1/2 amounts and activity, but increased CYP3A6 expression by 40% (p<0.05). In vitro, compared with serum from control rabbits (S(CONT)), incubation of serum from rabbits with TIIR (S(TIIR)) for 4 and 24h with hepatocytes from rabbits with TIIR (H(TIIR)) reduced CYP1A2 and CYP3A6 activity (p<0.05) and increased the formation of NO* and MDA. In rabbits with TIIR pretreated with U74389G, the S(TIIR+U) failed to reduce CYP1A2 activity or to increase MDA, although increased NO* and further reduced CYP3A6 activity. On the other hand, in hepatocytes harvested from rabbits with TIIR pretreated with U74389G, S(TIIR) did not decrease CYP1A2 activity and did not enhance MDA, but still increased NO*. In vitro, the reduction of CYP1A2 and CYP3A6 activity by S(TIIR) is not associated to NF-kappaB activation. In conclusion, U74389G prevents CYP1A1/2 down-regulation and decrease in activity by a double mechanism: hindering the release of serum mediators and by averting intracellular events, effect possibly associated with its antioxidant activity. On the other hand, U74389G up-regulates CYP3A6 but inhibits its catalytic activity.
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Affiliation(s)
- Mehrzad Taherzadeh
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Que., Canada
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Kourylko O, Fradette C, Arcand M, du Souich P. MODULATION OF CYP1A2 AND CYP3A6 CATALYTIC ACTIVITIES BY SERUM FROM RABBITS WITH A TURPENTINE-INDUCED INFLAMMATORY REACTION AND INTERLEUKIN 6. Drug Metab Dispos 2005; 34:27-35. [PMID: 16204464 DOI: 10.1124/dmd.105.006528] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Inflammatory reactions reduce the activity of cytochrome P450 isoforms. The aim of the study was to determine the mechanisms underlying the decrease in CYP1A2 and CYP3A6 catalytic activities produced by serum from rabbits with a turpentine-induced inflammatory reaction (S(TIIR)) and interleukin 6 (IL-6). S(TIIR) and IL-6 were incubated with cultured primary hepatocytes from control rabbits (H(CONT)), and from rabbits with a turpentine-induced inflammatory reaction (H(TIIR)) in the absence or presence of pyrrolidine dithiocarbamate (PDTC), an antioxidant and inhibitor of nuclear factor kappaB transcription; 2'-amino-3'-methoxyflavone (PD98059), an inhibitor of extracellular signal-related kinase (Erk1/2); 4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole (SB203580), an inhibitor of p38MAPK; Nomega-nitro-L-arginine methyl ester, an inhibitor of nitric-oxide synthase 2 (NOS2); the combination of PDTC, PD98059, and SB203580; and genistein, an inhibitor of Janus-associated protein tyrosine kinase (JAK). After 4 and 24 h of incubation of H(CONT) with S(TIIR) and IL-6, CYP1A2 activity was reduced without changes in expression; the reduction in activity was partially prevented by the inhibition of JAK, Erk1/2, and NOS2. In H(CONT), S(TIIR) and IL-6 did not affect CYP3A6 activity; however, PDTC reduced CYP3A6 activity by 40 and 80% after 4 and 24 h of incubation. In H(TIIR), S(TIIR) and IL-6 reduced both CYP1A2 and CYP3A6 activities; this decrease is partially prevented by inhibitors of protein tyrosine kinases, Erk1/2, and NOS2. In H(TIIR), SB203580 increased CYP3A6 activity in a dose-dependent manner without changes in protein expression. These results show that the signal transduction pathways mediating the decrease in CYP1A2 and 3A6 activity, produced by S(TIIR) and IL-6, involve JAK, Erk1/2, and NOS2.
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Affiliation(s)
- Oksana Kourylko
- Département de pharmacologie, Local R-412, Faculté de médecine, Université de Montréal, Québec, Canada, H3C 3J7
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Levitchi M, Fradette C, Bleau AM, Michaud D, Kourylko O, Arcand M, du Souich P. Signal transduction pathways implicated in the decrease in CYP1A1, 1A2 and 3A6 activity produced by serum from rabbits and humans with an inflammatory reaction. Biochem Pharmacol 2004; 68:573-82. [PMID: 15242823 DOI: 10.1016/j.bcp.2004.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2003] [Accepted: 04/13/2004] [Indexed: 10/26/2022]
Abstract
Incubation of serum from rabbits with a turpentine-induced inflammatory reaction and from humans with an upper respiratory viral infection with hepatocytes from rabbits with a turpentine-induced inflammatory reaction for 4h reduces total cytochrome P450 content and activity of cytochrome P450 isoforms CYP1A1/1A2 and 3A6 without affecting the expression of these proteins. To document the signal transduction pathways implicated in the decrease in CYP1A1/1A2 and 3A6 activity, hepatocytes from rabbits with a turpentine-induced inflammatory reaction were incubated with serum from rabbits with a turpentine-induced inflammatory reaction, serum from individuals with a viral infection and interleukin-6 for 4h in presence of inhibitors of protein kinases. The sera-induced decrease in CYP1A1/1A2 and 3A6 activity was partially prevented by the inhibition of Janus-associated protein tyrosine kinase, double-stranded RNA-dependent protein kinase, protein kinase C, and p42/44 mitogen-activated protein kinase. The serum from rabbits with a turpentine-induced inflammatory reaction increased the phosphorylation of Erk1/2, effect prevented by PD98059 but not by bis-indolylmaleimide, a specific inhibitor of protein kinase C. The results demonstrated that the decrease in total cytochrome P450 content and in CYP1A1/1A2 and 3A6 activity by sera and interleukin-6 involves the activation of protein tyrosine kinases, p42/44 mitogen-activated protein kinase and protein kinase C. Indirect evidence supported that nitric oxide is implicated in the decrease in activity of these enzymes.
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Affiliation(s)
- Mihaela Levitchi
- Département de Pharmacologie, Faculté de Médecine, Université de Montréal, Montreal, Quebec, Canada H3C 3J7
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Fradette C, Yamaguchi N, du Souich P. 5-Hydroxytryptamine is biotransformed by CYP2C9, 2C19 and 2B6 to hydroxylamine, which is converted into nitric oxide. Br J Pharmacol 2004; 141:407-14. [PMID: 14718257 PMCID: PMC1574215 DOI: 10.1038/sj.bjp.0705632] [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] [Indexed: 02/01/2023] Open
Abstract
There is circumstantial evidence suggesting that 5-hydroxytryptamine (5-HT) could be biotransformed by enzymatic systems other than monoamino oxidase A, and that the isoforms of cytochrome P450 may be a source of nitric oxide. This study aimed to assess whether cytochrome P450 contributes to 5-HT biotransformation, and to provide evidence that 5-HT metabolism generates nitric oxide. Addition of 5-HT to cultured hepatocytes yielded 5-hydroxyindol acetic acid, a formation modulated by cytochrome P450 enzyme inducers and inhibitors. Recombinant human CYP2B6, 2C9 and 2C19 biotransformed 5-HT in 5-hydroxyindol acetic acid, but not CYP1A2, 2D6 or 3A4. Cultured hepatocytes with 5-HT generated nitric oxide, the amount of which was altered by cytochrome P450 enzyme inducers and inhibitors. In the presence of CYP2B6, 2C9 and 2C19, 5-HT relaxed precontracted isolated aortic rings, with or without endothelium, an effect prevented by the addition of methylene blue and an inhibitor of catalase, but not by myoglobin. In the absence of catalase, hydroxylamine was always assayed as a byproduct of 5-HT metabolism. In conclusion, CYP2B6, 2C9 and 2C19 biotransform 5-HT, yielding hydroxylamine, which is converted to nitric oxide in the presence of catalase. British Journal of Pharmacology (2004) 141, 407-414. doi:10.1038/sj.bjp.0705632
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Affiliation(s)
- Caroline Fradette
- Department of Pharmacology, Faculty of Medicine, University of Montréal, P.O. Box 6128, Stat. Centre-Ville, Montréal, Québec, Canada H3C 3J7
| | - Nobuharu Yamaguchi
- Faculty of Pharmacy, University of Montréal, P.O. Box 6128, Stat. Centre-Ville, Montréal, Québec, Canada H3C 3J7
| | - Patrick du Souich
- Department of Pharmacology, Faculty of Medicine, University of Montréal, P.O. Box 6128, Stat. Centre-Ville, Montréal, Québec, Canada H3C 3J7
- Author for correspondence:
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Fradette C, Souich PD. Hypoxia-inducible factor-1 and activator protein-1 modulate the upregulation of CYP3A6 induced by hypoxia. Br J Pharmacol 2003; 140:1146-54. [PMID: 14559859 PMCID: PMC1574128 DOI: 10.1038/sj.bjp.0705543] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
1. Moderate hypoxia in vivo and serum from rabbits subjected to moderate hypoxia (SHYPO) in vitro reduce CYP1A1 and 1A2 p450 isoforms and upregulate CYP3A6. The aim of this project was to investigate the signal transduction pathways implicated in the upregulation of CYP3A6 expression by hypoxia. 2. Hypoxia in vivo and SHYPO in vitro increased the expression of hypoxia-inducible factor-1alpha (HIF-1alpha) and c-jun, as well as CYP3A6. By electrophoresis mobility shift assay, it was shown that HIF-1 and activator protein-1 (AP-1) bind to CYP3A6 oligonucleotide probe after exposure to hypoxia in vivo and SHYPO in vitro. The effects of hypoxia in vivo or SHYPO in vitro were reproduced by CoCl2 and lead acetate, activators of HIF-1 and AP-1, respectively. 2. PD98059, a p42/44 MAPK inhibitor, prevented the increase of CYP3A6 and c-jun, but did not impede the increase of HIF-1alpha and binding to CYP3A6 oligonucleotide probe. Genistein, an inhibitor of protein tyrosine kinases (PTKs), prevented the increase in HIF-1alpha, c-jun and CYP3A6, as well as HIF-1 and AP-1 binding to CYP3A6 oligonucleotide probe. Moreover, hypoxia in vivo induced constitutive androstane receptor (CAR) as well as CAR binding to the CYP3A6 oligonucleotide probe, but not the pregnane X receptor. 4. In conclusion, hypoxia in vivo and SHYPO induce the expression of CYP3A6. The in vitro induction of CYP3A6 by SHYPO is PTK- and p42/44 MAPK-dependent. The present data support the hypothesis that HIF-1 and AP-1 are part of the signalling pathway leading to CYP3A6 induction by hypoxia.
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Affiliation(s)
- Caroline Fradette
- Department of Pharmacology, Faculty of Medicine, University of Montréal, PO Box 6128, Stat. Centre-Ville, Montréal, Québec, Canada H3C 3J7
| | - Patrick du Souich
- Department of Pharmacology, Faculty of Medicine, University of Montréal, PO Box 6128, Stat. Centre-Ville, Montréal, Québec, Canada H3C 3J7
- Author for correspondence:
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Bleau AM, Maurel P, Pichette V, Leblond F, du Souich P. Interleukin-1beta, interleukin-6, tumour necrosis factor-alpha and interferon-gamma released by a viral infection and an aseptic inflammation reduce CYP1A1, 1A2 and 3A6 expression in rabbit hepatocytes. Eur J Pharmacol 2003; 473:197-206. [PMID: 12892839 DOI: 10.1016/s0014-2999(03)01968-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Inflammation reduces activity and expression of hepatic cytochrome P450 (P450) and therefore diminishes drug biotransformation. This study aimed to identify the serum mediators triggered by a viral infection and an aseptic inflammation that downregulate P450 isoforms. Incubation of hepatocytes with serum from rabbits with a turpentine-induced inflammation or humans with a viral infection decreased the amount of cytochrome 1A1 (CYP1A1), 1A2 and 3A6 mRNA and apoproteins. By serum fractionation and immuno-neutralization, we showed that in the aseptic inflammation, interleukin-6 and, to a lesser degree, interleukin-1beta are involved in the downregulation of all three isoforms. In serum from humans with a viral infection, interleukin-1beta, interleukin-6, interferon-gamma and tumour necrosis factor-alpha contribute to the downregulation of P450 isoforms. CYP1A1 and 1A2 are regulated by serum mediators at the transcriptional level, while the expression of CYP3A6 appears to be under the control of pre- and posttranscriptional mechanisms.
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Affiliation(s)
- Anne-Marie Bleau
- Département de Pharmacologie, Faculté de Médecine, Université de Montréal, C.P. 6128, Succ. "Centre ville", Montréal, Québec, Canada H3C 3J7
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18
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Fradette C, Bleau AM, Pichette V, Chauret N, du Souich P. Hypoxia-induced down-regulation of CYP1A1/1A2 and up-regulation of CYP3A6 involves serum mediators. Br J Pharmacol 2002; 137:881-91. [PMID: 12411420 PMCID: PMC1573556 DOI: 10.1038/sj.bjp.0704933] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. Acute moderate hypoxia modifies the catalytic activity and expression of certain isoenzymes of hepatic cytochrome P450 (P450). The aim of this study was to document whether hypoxia affects hepatic P450 directly or through the release of serum mediators. 2. Rabbits were subjected to a FiO(2) of 8% for 48 h, sacrificed, and serum and hepatocytes were isolated; hepatocytes from control and rabbits with hypoxia were incubated with serum from control and hypoxic rabbits for 4 and 24 h, and total P450 content, CYP1A1, 1A2 and 3A6 activities and expressions were assessed. Sera were fractionated by size exclusion chromatography and fractions tested for their ability to modify activity and amount of P450, and serum mediators were identified through neutralization experiments. 3. Total serum and fractions with proteins of 15-23 and 65-94 kDa of M(r) reduced P450 content and expression of CYP1A1, 1A2 and 3A6, as well as CYP1A1, 1A2 and 3A6 mRNA. Total serum and the fraction with 32-44 kDa proteins increased CYP3A6 activity and protein and mRNA. The serum mediators implicated in the decrease in activity and expression of CYP1A1, 1A2 and 3A6 were interferon-gamma (IFN-gamma), interleukin-1beta (IL-1beta) and IL-2. Erythropoietin (Epo) was partly responsible for the increase in P450 content and CYP3A6 expression. 4. In conclusion, acute moderate hypoxia diminishes the activity and expression of CYP1A1, 1A2 and CYP1A1, 1A2 mRNA, and increases CYP3A6 protein, activity and CYP3A6 mRNA. Several mechanisms contribute to these changes in P450, among them the release of cytokines acting as serum mediators.
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Affiliation(s)
- Caroline Fradette
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada, H3C 3J7
| | - Anne-Marie Bleau
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada, H3C 3J7
| | - Vincent Pichette
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada, H3C 3J7
| | - Nathalie Chauret
- Merck Frosst Centre for Therapeutic Research, P.O. Box 1005, Pointe Claire-Dorval, Québec, Canada H9R 4P8
| | - Patrick du Souich
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada, H3C 3J7
- Author for correspondence:
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19
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Abstract
During infection or inflammation, the expression of cytochrome P450 and its dependent biotransformation pathways are modified. This results in a change in the capacity of the liver to handle drugs and in alterations in the production and elimination of endogenous substances throughout the body. The majority of the CYP isoforms are modified at pre-translational steps in protein synthesis, and, in most cases, cytokines are involved as mediators of the response. Recent information suggests that inflammatory responses that are localized to the CNS cause a loss of CYP within the brain. This is accompanied by a parallel down-regulation of CYP in peripheral organs that is mediated by a signaling pathway between the brain and periphery. This review covers the loss that occurs in the major mammalian CYP families in response to infection/inflammation and the mediator pathways that are key to this response.
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Affiliation(s)
- K W Renton
- Department of Pharmacology, Sir Charles Tupper Medical Building, Dalhousie University Halifax, Nova Scotia, Canada B3H 4H7.
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20
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Bleau AM, Levitchi MC, Maurice H, du Souich P. Cytochrome P450 inactivation by serum from humans with a viral infection and serum from rabbits with a turpentine-induced inflammation: the role of cytokines. Br J Pharmacol 2000; 130:1777-84. [PMID: 10952665 PMCID: PMC1572253 DOI: 10.1038/sj.bjp.0703486] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Serum from humans with an acute upper respiratory viral infection and from rabbits with turpentine-induced inflammation reduce the catalytic activity of hepatic cytochrome P450 (P450). The aim of this study was to identify the serum mediators responsible for the decrease in P450 activity. Rabbit and human sera were fractionated by size exclusion chromatography and the fractions tested for their ability to reduce the activity and amount of P450 after 4 h of incubation with hepatocytes from turpentine-treated rabbits (H(INF)). Rabbit and human sera decreased P450 activity by around 40% without any change in the amount of CYP1A1 and 1A2 apoproteins. In rabbit serum, the fraction containing proteins of M(r) 23-15 kDa decreased P450 content by 41%, but did not alter the amount of the apoproteins. Anti-IL-6 antibody added to the M(r) 23-15 kDa fraction restored P450 content to 97% of control values, while anti-IL-1beta, TNF-alpha and IFN-gamma antibodies had no effect. Supporting the role of IL-6, incubation of H(INF) in the presence of IL-6 for 4 h reduced P450 content by 40%. In human serum, the fraction containing proteins of M(r) >95 kDa lowered P450 content by 43% without modifying the amounts of CYP1A1/2. Neutralization experiments showed that IFN-gamma, IL-6, and IL-1beta contributed to the decrease in P450 content. In conclusion, the present results demonstrate that IL-6, and IFN-gamma, IL-6 and IL-1beta are the serum mediators released in vivo by a turpentine-induced inflammatory reaction in the rabbit and an upper respiratory viral infection in humans, respectively, inactivating hepatic P450.
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Affiliation(s)
- Anne-Marie Bleau
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada
| | - Mihaela C Levitchi
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada
| | - Hélène Maurice
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada
| | - Patrick du Souich
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada
- Author for correspondence:
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Galal A, du Souich P. 21-aminosteroids prevent the down-regulation of hepatic cytochrome P450 induced by hypoxia and inflammation in conscious rabbits. Br J Pharmacol 1999; 128:374-9. [PMID: 10510447 PMCID: PMC1571640 DOI: 10.1038/sj.bjp.0702796] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1 This study was conducted to assess whether a 21-aminosteroid, U74389G, could prevent the down-regulation of hepatic cytochrome P450 (P450) induced by acute moderate hypoxia or an inflammatory reaction. 2 The rabbits of two groups (n = 6 per group) were subjected to acute moderate hypoxia (PaO2 approximately 35 mmHg), one pre-treated with U74389G (3 mg kg-1 i.v. every 6 h, for 48 h). The rabbits of two other groups received 5 ml of turpentine s.c., one of them being pre-treated with U74389G (3 mg kg-1 i.v. every 6 h, for 72 h). The kinetics of theophylline (2.5 mg kg-1) were assessed to evaluate the activity of the P450. Once the rabbits were sacrificed, the P450 content and the amount of thiobarbituric acid reactive substances (TBARS), a marker of lipid peroxidation, were estimated in the liver. 3 Compared with control rabbits, hypoxia and inflammation increased theophylline plasma concentrations, as a result of a decrease in theophylline systemic clearance (P<0.05). Both experimental conditions reduced hepatic content of P450 by 40-50% (P<0.05) and increased the amount of hepatic TBARS by around 50% (P<0.05). Pre-treatment with U74389G prevented the hypoxia- and inflammation-induced decrease in theophylline systemic clearance, the down-regulation of hepatic P450, and the increase in liver TBARS. 4 It is concluded that in the rabbit, U74389G prevents hepatic P450 depression produced by acute moderate hypoxia and a turpentine-induced inflammatory reaction, possibly by eliciting a radical quenching antioxidant activity.
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Affiliation(s)
- Ahmed Galal
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada
| | - Patrick du Souich
- Department of Pharmacology, Faculty of Medicine, University of Montréal, Montréal, Québec, Canada
- Author for correspondence:
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22
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Kurdi J, Maurice H, El-Kadi AOS, Ong H, Dalkara S, Bélanger PM, du Souich P. Effect of hypoxia alone or combined with inflammation and 3-methylcholanthrene on hepatic cytochrome P450 in conscious rabbits. Br J Pharmacol 1999; 128:365-73. [PMID: 10510446 PMCID: PMC1571639 DOI: 10.1038/sj.bjp.0702795] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/1999] [Revised: 06/16/1999] [Accepted: 06/22/1999] [Indexed: 11/08/2022] Open
Abstract
1 To investigate the effect of moderate hypoxia alone or combined with an inflammatory reaction or after 3-methylcholanthrene (3MC) pre-treatment on cytochrome P450 (P450), conscious rabbits were exposed for 24 h to a fractional concentration of inspired O2 of 10% (mean PaO2 of 34 mmHg). Hypoxia decreased theophylline metabolic clearance (ClM) from 1.73+/-0.43 to 1.48+/-0.13 ml min-1 kg-1 (P<0. 05), and reduced (P<0.05) the formation clearance of theophylline metabolites, 3-methylxanthine (3MX), 1-methyluric acid (1MU) and 1,3-dimethyluric acid (1,3DMU). Hypoxia reduced the amount of CYP1A1 and 1A2 but increased CYP3A6 proteins. 2 Turpentine-induced inflammatory reaction reduced (P<0.05) the formation clearance of 3MX, 1MU, and 1,3DMU, and diminished the amount of CYP1A1, 1A2 and 3A6 proteins. However, when combined with hypoxia, inflammation partially prevented the decrease in ClM, especially by impeding the reduction of 1,3DMU. The amount of CYP1A1 and 1A2 remained reduced but the amount of CYP3A6 protein returned to normal values. 3 Pre-treatment with 3MC augmented the ClM by 114% (P<0.05) due to the increase in the formation clearance of 3MX, 1MU and 1,3DMU. 3MC treatment increased the amount of CYP1A1 and 1A2 proteins. Pre-treatment with 3MC prevented the hypoxia-induced decrease in amount and activity of the P450. 4 It is concluded that acute moderate hypoxia and an inflammatory reaction individually reduce the amount and activity of selected apoproteins of the P450. However, the combination of hypoxia and the inflammatory reaction restores P450 activity to near normal values. On the other hand, pre-treatment with 3MC prevents the hypoxia-induced depression of the P450.
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Affiliation(s)
- J Kurdi
- Department of Pharmacology, Faculty of Medicine, C.P. 6128, Succ. ‘Centre-ville', Montréal, Québec, Canada H3C 3J7
| | - H Maurice
- Department of Pharmacology, Faculty of Medicine, C.P. 6128, Succ. ‘Centre-ville', Montréal, Québec, Canada H3C 3J7
| | - A O S El-Kadi
- Department of Pharmacology, Faculty of Medicine, C.P. 6128, Succ. ‘Centre-ville', Montréal, Québec, Canada H3C 3J7
| | - H Ong
- Faculty of Pharmacy, University of Montréal, C.P. 6128, Succ. ‘Centre-ville', Montréal, Québec, Canada H3C 3J7
| | - S Dalkara
- Faculty of Pharmacy, University of Laval, Québec, Canada
| | - P M Bélanger
- Faculty of Pharmacy, University of Laval, Québec, Canada
| | - P du Souich
- Department of Pharmacology, Faculty of Medicine, C.P. 6128, Succ. ‘Centre-ville', Montréal, Québec, Canada H3C 3J7
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Guerre P, Larrieu G, Burgat V, Galtier P. Cytochrome P450 decreases are correlated to increased microsomal oxidative damage in rabbit liver and primary cultures of rabbit hepatocytes exposed to AFB1. Toxicol Lett 1999; 104:117-25. [PMID: 10048757 DOI: 10.1016/s0378-4274(98)00352-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although numerous studies report hepatic drug metabolizing enzyme alterations during aflatoxicosis, the mechanisms involved in P450 decreases remain to be established. The purpose of this work is to investigate whether increased oxidative damage revealed by the detection of malondialdehyde (MDA), lipofuscin substances, and conjugated dienes in microsomes, could explain the decreased P450 content. Studies were conducted with two different doses of aflatoxin B1 (AFB1), both in vivo in rabbits and ex vivo in primary cultures of rabbit hepatocytes, in the presence or absence of beta-naphthoflavone or rifampicin used as respective P450 inducers. Strong negative correlations were observed between MDA and P450 contents, both in vivo and ex vivo, whereas rifampicin appears to protect the hepatocytes from oxidative damage but not AFB1 toxicity. Positive correlation were also obtained between MDA formation and lactate dehydrogenase (LDH), aspartate aminotransferase (ASAT) or alanine amino-transferase (ALAT) releases, used as non-specific markers of AFB1 toxicity. Taken together these results suggest that the dramatic decreases of cytochrome P450 observed in vivo during aflatoxicosis could be linked, at least in part, to microsomal oxidative damage.
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Affiliation(s)
- P Guerre
- Département des Sciences Biologiques et Fonctionnelles, Pharmacie-Toxicologie, E.N.V.T., Toulouse, France
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24
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El-Kadi AO, du Souich P. Depression of the hepatic cytochrome P450 by an acute inflammatory reaction: characterization of the nature of mediators in human and rabbit serum, and in the liver. Life Sci 1998; 63:1361-70. [PMID: 9768874 DOI: 10.1016/s0024-3205(98)00400-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
There is increasing evidence suggesting that several mediators are involved in the cascade of events leading to the depression of the cytochrome P450 (P450) by an inflammatory reaction. The present study aimed to confirm the presence of mediators in the serum (RS(INFLA)) and hepatocytes (H(INFLA)) of rabbits with an acute inflammatory reaction, and in the serum of humans with an acute upper respiratory tract viral infection (HS(URTVI)). The inflammatory reaction was induced by the s.c. injection of 5 ml of turpentine. Incubation of RS(INFLA) or HS(URTVI) with H(INFLA) depressed the P450, diminished the formation of theophylline metabolites (3-methylxanthine, 1-methyluric acid, and 1,3-dimethyluric acid), and increased lipid peroxidation. The addition of preheated RS(INFLA) or HS(URTVI) to H(INFLA) did not diminish the amount of P450 or theophylline metabolites, and prevented the increase in lipid peroxidation. Incubating the filtrate of RS(INFLA) or HS(URTVI) dialyzed through membranes with cut-off of 10, 30, 50 and 100 kd, with H(INFLA) showed that rabbit and human mediators have molecular weights ranging from 10 to 30 kd. Incubation of H(INFLA) with hepatocytes from control rabbits (H(CONT)) did not decrease further the P450. However, when RS(INFLA) was added to co-cultured H(CONT) + H(INFLA), the depression of P450 was 37% greater (p<0.05), and the amount of theophylline metabolites generated was around 30% (p<0.05) smaller than that observed when H(CONT) or H(INFLA) were incubated with RS(INFLA). Based on the present results we may speculate that human and rabbit serum mediators are proteins of molecular weights ranging from 10 to 30 kd, and in addition, primed hepatocytes once exposed to the serum mediators release mediators able to depress the P450 in H(CONT).
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Affiliation(s)
- A O El-Kadi
- Department of Pharmacology, Faculty of Medicine, Universit'e de Montréal, Québec, Canada
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