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The Effect of the Selective N-methyl-D-aspartate (NMDA) Receptor GluN2B Subunit Antagonist CP-101,606 on Cytochrome P450 2D (CYP2D) Expression and Activity in the Rat Liver and Brain. Int J Mol Sci 2022; 23:ijms232213746. [PMID: 36430225 PMCID: PMC9691159 DOI: 10.3390/ijms232213746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/05/2022] [Accepted: 11/07/2022] [Indexed: 11/11/2022] Open
Abstract
The CYP2D enzymes of the cytochrome P450 superfamily play an important role in psychopharmacology, since they are engaged in the metabolism of psychotropic drugs and endogenous neuroactive substrates, which mediate brain neurotransmission and the therapeutic action of those drugs. The aim of this work was to study the effect of short- and long-term treatment with the selective antagonist of the GluN2B subunit of the NMDA receptor, the compound CP-101,606, which possesses antidepressant properties, on CYP2D expression and activity in the liver and brain of male rats. The presented work shows time-, organ- and brain-structure-dependent effects of 5-day and 3-week treatment with CP-101,606 on CYP2D. Five-day treatment with CP-101,606 increased the activity and protein level of CYP2D in the hippocampus. That effect was maintained after the 3-week treatment and was accompanied by enhancement in the CYP2D activity/protein level in the cortex and cerebellum. In contrast, a 3-week treatment with CP-101,606 diminished the CYP2D activity/protein level in the hypothalamus and striatum. In the liver, CP-101,606 decreased CYP2D activity, but not the protein or mRNA level, after 5-day or 3-week treatment. When added in vitro to liver microsomes, CP-101,606 diminished the CYP2D activity during prolonged incubation. While in the brain, the observed decrease in the CYP2D activity after short- and long-term treatment with CP-101,606 seems to be a consequence of the drug effect on enzyme regulation. In the liver, the direct inhibitory effect of reactive metabolites formed from CP-101,606 on the CYP2D activity may be considered. Since CYP2Ds are engaged in the metabolism of endogenous neuroactive substances, it can be assumed that apart from antagonizing the NMDA receptor, CP-101,606 may modify its own pharmacological effect by affecting brain cytochrome P450. On the other hand, an inhibition of the activity of liver CYP2D may slow down the metabolism of co-administered substrates and lead to pharmacokinetic drug-drug interactions.
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Niwa T, Sasaki S, Yamamoto Y, Tanaka M. Effect of Human Cytochrome P450 2D6 Polymorphism on Progesterone Hydroxylation. Eur J Drug Metab Pharmacokinet 2022; 47:741-747. [PMID: 35838883 DOI: 10.1007/s13318-022-00784-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUND AND OBJECTIVES Herein, hydroxylation activities at the 6β-position and 21-position of progesterone mediated by human cytochrome P450 (CYP) 2D6 and its variants and the effects of psychotropic drugs on these hydroxylation activities were compared to clarify whether CYP2D6 polymorphisms and psychotropic drugs impact neurosteroid levels in the brain. METHODS Progesterone was incubated with CYP2D6.1, CYP2D6.2 (Arg296Cys, Ser486Thr), CYP2D6.10 (Pro34Ser, Ser486Thr), and CYP2D6.39 (Ser486Thr) in the absence or presence of typical psychotropic drugs (fluvoxamine, fluoxetine, paroxetine, fluphenazine, and milnacipran) and endogenous steroids (testosterone and cortisol). Then, 6β- and 21-hydroxyprogesterone levels were determined by high-performance liquid chromatography. RESULTS Although the Michaelis-Menten constants (Km) for progesterone 6β- and 21-hydroxylation reactions mediated by the different CYP2D6 variants were similar, the maximal velocity (Vmax) values of the reactions mediated by CYP2D6.1 and CYP2D6.2 were the highest, followed by those mediated by CYP2D6.39 and CYP2D6.10. Thus, the of progesterone 6β- and/or 21-hydroxylation reactions mediated by CYP2D6.1 and CYP2D6.2 showed the highest Vmax/Km values, followed by the reactions mediated by CYP2D6.39. All investigated compounds inhibited progesterone 21-hydroxylation mediated by CYP2D6 variants at high concentrations. Interestingly, at low concentrations, fluoxetine increased progesterone 21-hydroxylation mediated by CYP2D6.1, but not that mediated by CYP2D6.2 or CYP2D6.10. In addition, the Km value for CYP2D6.2 was elevated in the presence of fluoxetine, whereas the value for CYP2D6.1 was unaltered; however, Vmax values of both CYP2D6.1 and CYP2D6.2 were increased. Paroxetine competitively inhibited CYP2D6.1- and CYP2D6.2-mediated progesterone 21-hydroxylation. CONCLUSIONS These results suggest that CYP2D6 polymorphism can affect the stimulation/inhibition of progesterone 21-hydroxylation.
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Affiliation(s)
- Toshiro Niwa
- School of Pharmacy, Shujitsu University, 1-6-1 Nishigawara, Naka-ku, Okayama, 703-8516, Japan.
| | - Shoko Sasaki
- School of Pharmacy, Shujitsu University, 1-6-1 Nishigawara, Naka-ku, Okayama, 703-8516, Japan
| | - Yuka Yamamoto
- School of Pharmacy, Shujitsu University, 1-6-1 Nishigawara, Naka-ku, Okayama, 703-8516, Japan
| | - Mayu Tanaka
- School of Pharmacy, Shujitsu University, 1-6-1 Nishigawara, Naka-ku, Okayama, 703-8516, Japan
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Daniel WA, Bromek E, Danek PJ, Haduch A. The mechanisms of interactions of psychotropic drugs with liver and brain cytochrome P450 and their significance for drug effect and drug-drug interactions. Biochem Pharmacol 2022; 199:115006. [PMID: 35314167 DOI: 10.1016/j.bcp.2022.115006] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/11/2022] [Accepted: 03/14/2022] [Indexed: 02/08/2023]
Abstract
Cytochrome P450 (CYP) plays an important role in psychopharmacology. While liver CYP enzymes are responsible for the biotransformation of psychotropic drugs, brain CYP enzymes are involved in the local metabolism of these drugs and endogenous neuroactive substances, such as neurosteroids, and in alternative pathways of neurotransmitter biosynthesis including dopamine and serotonin. Recent studies have revealed a relation between the brain nervous system and cytochrome P450, indicating that CYP enzymes metabolize endogenous neuroactive substances in the brain, while the brain nervous system is engaged in the central neuroendocrine and neuroimmune regulation of cytochrome P450 in the liver. Therefore, the effect of neuroactive drugs on cytochrome P450 should be investigated not only in vitro, but also at in vivo conditions, since only in vivo all mechanisms of drug-enzyme interaction can be observed, including neuroendocrine and neuroimmune modulation. Psychotropic drugs can potentially affect cytochrome P450 via a number of mechanisms operating at the level of the nervous, hormonal and immune systems, and the liver. Their effect on cytochrome P450 in the brain is often different than in the liver and region-dependent. Since psychotropic drugs can affect cytochrome P450 both in the liver and brain, they can modify their own pharmacological effect at both pharmacokinetic and pharmacodynamic level. The article describes the mechanisms by which psychotropic drugs can change the expression/activity of cytochrome P450 in the liver and brain, and discusses the significance of those mechanisms for drug action and drug-drug interactions. Moreover, the brain CYP2D6 is considered as a potential target for psychotropics.
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Affiliation(s)
- Władysława A Daniel
- Department of Pharmacokinetics and Drug Metabolism, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland.
| | - Ewa Bromek
- Department of Pharmacokinetics and Drug Metabolism, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland
| | - Przemysław J Danek
- Department of Pharmacokinetics and Drug Metabolism, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland
| | - Anna Haduch
- Department of Pharmacokinetics and Drug Metabolism, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland
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Niwa T, Arima J, Michihiro Y. Role of amino acids at positions 34, 296, and 486 of cytochrome P450 2D6 in the stimulatory and inhibitory effects of psychotropic agents on dopamine formation from p-tyramine. Xenobiotica 2021; 51:1229-1235. [PMID: 34605737 DOI: 10.1080/00498254.2021.1989520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The effects of psychotropic agents such as fluvoxamine, fluoxetine, paroxetine, milnacipran, and fluphenazine on dopamine formation from p-tyramine catalysed by cytochrome P450 (CYP) 2D6.2 (Arg296Cys;Ser486Thr), CYP2D6.10 (Pro34Ser;Ser486Thr), and CYP2D6.39 (Ser486Thr) were compared with the effects on dopamine formation from p-tyramine by CYP2D6.1. Michaelis constants (Km) and maximal velocity (kcat) values for dopamine formation and inhibition constants (Ki) of the psychotropic agents were determined.For CYP2D6.39, the kcat values for fluvoxamine, fluoxetine, and milnacipran, but not for paroxetine and fluphenazine, gradually increased with increasing concentrations, indicating activation of the catalysed reaction.Fluphenazine competitively inhibited dopamine formation catalysed by all variants, with a higher Ki value for CYP2D6.10. Among the three compounds that have a trifluoromethyl group in their chemical structure, only fluvoxamine and fluoxetine, as well as milnacipran that does not have this group, decreased Km values and/or increased kcat values for dopamine formation, suggesting that the group may not be essential for the activation.These findings indicate that substitution of amino acids at positions 34 and 486 can affect the affinity (Km) and enzymatic activity (kcat), respectively, for milnacipran and that the effect of substitution of arginine to cysteine at the 296th position on the activation would be effector dependent.
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Affiliation(s)
- Toshiro Niwa
- School of Pharmacy, Shujitsu University, Okayama, Japan
| | - Juri Arima
- School of Pharmacy, Shujitsu University, Okayama, Japan
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Micarelli A, Cormano A, Caccamo D, Alessandrini M. Olfactory-Related Quality of Life in Multiple Chemical Sensitivity: A Genetic-Acquired Factors Model. Int J Mol Sci 2019; 21:ijms21010156. [PMID: 31881664 PMCID: PMC6981591 DOI: 10.3390/ijms21010156] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 12/21/2019] [Accepted: 12/24/2019] [Indexed: 12/19/2022] Open
Abstract
Genetic polymorphisms as well as environmental exposures to chemical compounds, iatrogenic, psychological, and physical trauma may play a pathophysiological role in multiple chemical sensitivity (MCS) olfactory complaints, given that xenobiotic metabolism is influenced by sequence variations in genes of metabolizing enzymes. Thus, the aim of the present study was to depict-by means of multiple regression analysis-how different genetic conditions, grouped according to their function as well as clinical background and environmental exposure may interfere with those olfactory complaints referred by MCS patients. Therefore, MCS patients after gene polymorphism sequencing, the olfactory-related quality of life score-calculated by means of the Questionnaire of Olfactory Disorder in forty-six MCS patients-have been found to significantly rely on the phase I and II enzymes score and exposure to previous compounds and surgical treatments. The present work-implementing for the first time a genetic-acquired factors model on a regression analysis-further reinforces those theories, positing MCS as a complex, multifactorial, disease in which the genetic risk related to phase I and II enzymes involved in xenobiotic detoxification, olfactory, and neurodegenerative diseases play a necessary, but probably not sufficient role, along the pathophysiological route of the disease.
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Affiliation(s)
- Alessandro Micarelli
- Institute of Mountain Emergency Medicine, EURAC Research, I-39100 Bolzano, Italy
- ITER Center for Balance and Rehabilitation Research (ICBRR), 02032 Rome, Italy
- Correspondence:
| | | | - Daniela Caccamo
- Department of Biomedical Sciences, Dental Sciences and Morpho-functional Imaging, Polyclinic Hospital University, 98124 Messina, Italy;
| | - Marco Alessandrini
- Department of Clinical Sciences and Translational Medicine, University of Rome “Tor Vergata”, 00133 Rome, Italy;
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Rafehi M, Faltraco F, Matthaei J, Prukop T, Jensen O, Grytzmann A, Blome FG, Berger RG, Krings U, Vormfelde SV, Tzvetkov MV, Brockmöller J. Highly Variable Pharmacokinetics of Tyramine in Humans and Polymorphisms in OCT1, CYP2D6, and MAO-A. Front Pharmacol 2019; 10:1297. [PMID: 31736764 PMCID: PMC6831736 DOI: 10.3389/fphar.2019.01297] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 10/10/2019] [Indexed: 11/17/2022] Open
Abstract
Tyramine, formed by the decarboxylation of tyrosine, is a natural constituent of numerous food products. As an indirect sympathomimetic, it can have potentially dangerous hypertensive effects. In vitro data indicated that the pharmacokinetics of tyramine possibly depend on the organic cation transporter OCT1 genotype and on the CYP2D6 genotype. Since tyramine is a prototypic substrate of monoamine oxidase A (MAO-A), genetic polymorphisms in MAO-A may also be relevant. The aims of this study were to identify to what extent the interindividual variation in pharmacokinetics and pharmacodynamics of tyramine is determined by genetic polymorphisms in OCT1, CYP2D6, and MAO-A. Beyond that, we wanted to evaluate tyramine as probe drug for the in vivo activity of MAO-A and OCT1. Therefore, the pharmacokinetics, pharmacodynamics, and pharmacogenetics of tyramine were studied in 88 healthy volunteers after oral administration of a 400 mg dose. We observed a strong interindividual variation in systemic tyramine exposure, with a mean AUC of 3.74 min*µg/ml and a high mean CL/F ratio of 107 l/min. On average, as much as 76.8% of the dose was recovered in urine in form of the MAO-catalysed metabolite 4-hydroxyphenylacetic acid (4-HPAA), confirming that oxidative deamination by MAO-A is the quantitatively most relevant metabolic pathway. Systemic exposure of 4-HPAA varied only up to 3-fold, indicating no strong heritable variation in peripheral MAO-A activity. Systolic blood pressure increased by more than 10 mmHg in 71% of the volunteers and correlated strongly with systemic tyramine concentration. In less than 10% of participants, individually variable blood pressure peaks by >40 mmHg above baseline were observed at tyramine concentrations of >60 µg/l. Unexpectedly, the functionally relevant polymorphisms in OCT1 and CYP2D6, including the CYP2D6 poor and ultra-rapid metaboliser genotypes, did not significantly affect tyramine pharmacokinetics or pharmacodynamics. Also, the MOA-A genotypes, which had been associated in several earlier studies with neuropsychiatric phenotypes, had no significant effects on tyramine pharmacokinetics or its metabolism to 4-HPAA. Thus, variation in tyramine pharmacokinetics and pharmacodynamics is not explained by obvious genomic variation, and human tyramine metabolism did not indicate the existence of ultra-low or -high MAO-A activity.
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Affiliation(s)
- Muhammad Rafehi
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | - Frank Faltraco
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | - Johannes Matthaei
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | - Thomas Prukop
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | - Ole Jensen
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | - Aileen Grytzmann
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | - Felix G Blome
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | | | - Ulrich Krings
- Institute of Food Chemistry, Leibniz University, Hannover, Germany
| | - Stefan V Vormfelde
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | - Mladen V Tzvetkov
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | - Jürgen Brockmöller
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
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7
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Phenotyping of Human CYP450 Enzymes by Endobiotics: Current Knowledge and Methodological Approaches. Clin Pharmacokinet 2019; 58:1373-1391. [DOI: 10.1007/s40262-019-00783-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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8
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Haduch A, Daniel WA. The engagement of brain cytochrome P450 in the metabolism of endogenous neuroactive substrates: a possible role in mental disorders. Drug Metab Rev 2019; 50:415-429. [PMID: 30501426 DOI: 10.1080/03602532.2018.1554674] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The current state of knowledge indicates that the cerebral cytochrome P450 (CYP) plays an important role in the endogenous metabolism in the brain. Different CYP isoenzymes mediate metabolism of many endogenous substrates such as monoaminergic neurotransmitters, neurosteroids, cholesterol, vitamins and arachidonic acid. Therefore, these enzymes may affect brain development, susceptibility to mental and neurodegenerative diseases and may contribute to their pathophysiology. In addition, they can modify the therapeutic effects of psychoactive drugs at the place of their target action in the brain, where the drugs can act by affecting the metabolism of endogenous substrates. The article focuses on the role of cerebral CYP isoforms in the metabolism of neurotransmitters, neurosteroids, and cholesterol, and their possible involvement in animal behavior, as well as in stress, depression, schizophrenia, cognitive processes, learning, and memory. CYP-mediated alternative pathways of dopamine and serotonin synthesis may have a significant role in the local production of these neurotransmitters in the brain regions where the disturbances of these neurotransmitter systems are observed in depression and schizophrenia. The local alternative synthesis of neurotransmitters may be of great importance in the brain, since dopamine and serotonin do not pass the blood-brain barrier and cannot be supplied from the periphery. In vitro studies indicate that human CYP2D6 catalyzing dopamine and serotonin synthesis is more efficient in these reactions than the rat CYP2D isoforms. It suggests that these alternative pathways may have much greater significance in the human brain but confirmation of these assumptions requires further studies.
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Affiliation(s)
- Anna Haduch
- a Department of Pharmacokinetics and Drug Metabolism, Institute of Pharmacology , Polish Academy of Sciences , Kraków , Poland
| | - Władysława Anna Daniel
- a Department of Pharmacokinetics and Drug Metabolism, Institute of Pharmacology , Polish Academy of Sciences , Kraków , Poland
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10
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Koopmans AB, Vinkers DJ, Gelan PJ, Hoek HW, van Harten PN. CYP2D6 and CYP2C19 genotyping in psychiatric patients on psychotropic medication in the former Dutch Antilles. Pharmacogenomics 2017. [PMID: 28639468 DOI: 10.2217/pgs-2017-0011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIM This study was aimed to asses the prevalence of CYP2D6 and CYP2C19 polymorphisms in psychiatric patients and in volunteers from Dutch caribbean origin. METHODS In total, 435 individuals were genotyped for CYP2D6 and CYP2C19. Of these, 269 were psychiatric patients on psychotropic medication, living in Curaçao and 166 were volunteers from the Dutch Caribbean population. RESULTS No differences in prevalence of alleles were found. CONCLUSION Although prevalence of alleles appeared to be very different from African and Caucasian populations, the distribution into predicted phenotypes shows an equal distribution as in Caucasians.
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Affiliation(s)
- Anne B Koopmans
- Parnassia Psychiatric Institute, Department of Research, The Hague, The Netherlands.,University of Maastricht, School for Mental Health and Neuroscience, The Netherlands
| | - David J Vinkers
- University of Maastricht, School for Mental Health and Neuroscience, The Netherlands
| | | | - Hans W Hoek
- Parnassia Psychiatric Institute, Department of Research, The Hague, The Netherlands.,University Medical Center Groningen, University of Groningen, The Netherlands.,Mailman School of Public Health, Columbia University, New York, NY 10032, USA
| | - Peter N van Harten
- University of Maastricht, School for Mental Health and Neuroscience, The Netherlands.,Psychiatric Centre GGz Centraal, Innova, Research Department, Amersfoort, The Netherlands
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Taranu A, Colle R, Gressier F, El Asmar K, Becquemont L, Corruble E, Verstuyft C. Should a routine genotyping of CYP2D6 and CYP2C19 genetic polymorphisms be recommended to predict venlafaxine efficacy in depressed patients treated in psychiatric settings? Pharmacogenomics 2017; 18:639-650. [PMID: 28480819 DOI: 10.2217/pgs-2017-0003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
AIM The antidepressant venlafaxine (VEN) is metabolized by CYP2D6 and CYP2C19. The aim of this study was to assess the relevance of generalizing to daily practice the genotyping of CYP2D6 and CYP2C19 to predict VEN efficacy in depressed patients treated in psychiatric settings. PATIENTS & METHODS This study was nested in a naturalistic cohort, with 206 patients requiring a new antidepressant treatment and genotyped for CYP2D6 *3, *4, *5 del, *6, *2xN, *10, *41 and CYP2C19 *2, *3, *4, *5, *17 alleles. RESULTS CYP2D6 and CYP2C19 phenotypes were associated neither with the Hamilton depression rating scale score improvement, nor with response and remission. CONCLUSION Routine CYP2D6 and CYP2C19 genotyping cannot be recommended to predict VEN efficacy in depressed patients treated in psychiatry settings.
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Affiliation(s)
- Adela Taranu
- INSERM UMR1178, Team (Depression & Antidepressants), Faculté de Médecine Paris-Sud, Univ. Paris-Sud, Le Kremlin Bicêtre, France
| | - Romain Colle
- INSERM UMR1178, Team (Depression & Antidepressants), Faculté de Médecine Paris-Sud, Univ. Paris-Sud, Le Kremlin Bicêtre, France.,Service de Psychiatrie, Hôpital Bicêtre, Groupe Hospitalier Paris Sud, AP-HP, Le Kremlin Bicêtre, France
| | - Florence Gressier
- INSERM UMR1178, Team (Depression & Antidepressants), Faculté de Médecine Paris-Sud, Univ. Paris-Sud, Le Kremlin Bicêtre, France.,Service de Psychiatrie, Hôpital Bicêtre, Groupe Hospitalier Paris Sud, AP-HP, Le Kremlin Bicêtre, France
| | - Khalil El Asmar
- INSERM UMR1178, Team (Depression & Antidepressants), Faculté de Médecine Paris-Sud, Univ. Paris-Sud, Le Kremlin Bicêtre, France
| | - Laurent Becquemont
- INSERM UMR1178, Team (Depression & Antidepressants), Faculté de Médecine Paris-Sud, Univ. Paris-Sud, Le Kremlin Bicêtre, France.,Centre de Recherche Clinique (CRC), Hôpital Bicêtre, Groupe Hospitalier Paris Sud, AP-HP, Le Kremlin Bicêtre, France
| | - Emmanuelle Corruble
- INSERM UMR1178, Team (Depression & Antidepressants), Faculté de Médecine Paris-Sud, Univ. Paris-Sud, Le Kremlin Bicêtre, France.,Service de Psychiatrie, Hôpital Bicêtre, Groupe Hospitalier Paris Sud, AP-HP, Le Kremlin Bicêtre, France
| | - Céline Verstuyft
- INSERM UMR1178, Team (Depression & Antidepressants), Faculté de Médecine Paris-Sud, Univ. Paris-Sud, Le Kremlin Bicêtre, France.,Service de Génétique Moléculaire, Pharmacogénétique et Hormonologie, Hôpital Bicêtre, Groupe Hospitalier Paris Sud, AP-HP, Le Kremlin Bicêtre, France.,Centre de Ressources Biologiques, CRB Paris-Sud, Hôpital Bicêtre, Groupe Hospitalier Paris Sud, AP-HP, Le Kremlin Bicêtre, France
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12
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Effect of genetic polymorphism on the inhibition of dopamine formation from p -tyramine catalyzed by brain cytochrome P450 2D6. Arch Biochem Biophys 2017; 620:23-27. [DOI: 10.1016/j.abb.2017.03.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 03/14/2017] [Accepted: 03/19/2017] [Indexed: 02/05/2023]
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Toselli F, Dodd PR, Gillam EMJ. Emerging roles for brain drug-metabolizing cytochrome P450 enzymes in neuropsychiatric conditions and responses to drugs. Drug Metab Rev 2016; 48:379-404. [DOI: 10.1080/03602532.2016.1221960] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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14
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Stephens DB, de Leon J. CYP2D6 ultra-rapid metabolizer phenotype not associated with attempted suicide in a large sample of psychiatric inpatients. Pharmacogenomics 2016; 17:1295-304. [PMID: 27463022 DOI: 10.2217/pgs-2016-0086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIM Suicide accounts for over 800,000 deaths per year worldwide and is the tenth-leading cause of mortality in USA. Several studies have investigated cytochrome P450 CYP2D6 ultra-rapid metabolizer (UM) phenotype in relation to suicidality, with mixed results. This study tested the hypothesis of increased suicide risk among CYP2D6 UMs. PATIENTS & METHODS Among the 4264 state psychiatric hospital inpatients included, 2435 (57%) reported a prior suicide attempt. RESULTS No association between UM status and attempted suicide was observed in bivariate (odds ratio: 0.87; 95% CI: 0.53-1.25), multivariate (adjusted odds ratio: 0.89; 95% CI: 0.55-1.46), or risk-stratified analyses. CONCLUSION These results contrast with prior reports of increased suicidality among CYP2D6 UMs and highlight the pressing need to identify reliable screening methods to better address this persistent public health problem.
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Affiliation(s)
- Dustin B Stephens
- Department of Behavioral Science, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Jose de Leon
- Department of Psychiatry, University of Kentucky College of Medicine, Lexington, KY, USA
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15
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Vevelstad M, Øiestad EL, Bremer S, Bogen IL, Zackrisson AL, Arnestad M. Is toxicity of PMMA (paramethoxymethamphetamine) associated with cytochrome P450 pharmacogenetics? Forensic Sci Int 2016; 261:137-47. [PMID: 26930544 DOI: 10.1016/j.forsciint.2016.02.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Revised: 01/22/2016] [Accepted: 02/13/2016] [Indexed: 11/30/2022]
Abstract
In 2010-2013, 29 fatal intoxications related to the designer drug paramethoxymethamphetamine (PMMA, 4-methoxymethamphetamine) occurred in Norway. The current knowledge about metabolism and toxicity of PMMA in humans is limited. Metabolism by the polymorphic cytochrome P450 (CYP) 2D6 enzyme to the psychoactive metabolite 4-hydroxymethamphetamine (OH-MA), and possibly by additional enzymes, is suggested to be involved in its toxicity. The aim of this work was to study the association between CYP genetics, PMMA metabolism and risk of fatal PMMA toxicity in humans. The frequency distribution of clinically relevant gene variants of CYP2D6, CYP2C9, CYP2C19 and CYP3A5, and the phenotypic blood CYP2D6 metabolic ratio (OH-MA/PMMA) in particular, were compared in fatal PMMA intoxications (n=17) and nonfatal PMMA abuse controls (n=30), using non-abusers (n=305) as references for the expected genotype frequencies in the Norwegian population. Our study demonstrated that the CYP2D6 enzyme and genotype are important in the metabolism of PMMA to OH-MA in humans, but that other enzymes are also involved in this biotransformation. In the fatal PMMA intoxications, the blood concentrations of PMMA were higher and the CYP2D6 metabolic ratios were lower, than in the nonfatal PMMA abuse controls (median (range) 2.1 (0.03-5.0) vs 0.3 (0.1-0.9) mg/L, and ratio 0.6 (0.0-4.6) vs 2.1 (0.2-7.4) p=0.021, respectively). Overall, our findings indicated that, in most cases, PMMA death occurred rapidly and at an early stage of PMMA metabolism, following the ingestion of large and toxic PMMA doses. We could not identify any genetic CYP2D6, CYP2C9, CYP2C19 or CYP3A5 predictive marker on fatal toxicity of PMMA in humans. The overrepresentation of the CYP2D6 poor metabolizer (PM) genotype found in the nonfatal PMMA abuse controls warrants further investigations.
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Affiliation(s)
- Merete Vevelstad
- Division of Forensic Sciences, Norwegian Institute of Public Health (NIPH), P.O. Box 4404, Nydalen, N-0403 Oslo, Norway.
| | - Elisabeth Leere Øiestad
- Division of Forensic Sciences, Norwegian Institute of Public Health (NIPH), P.O. Box 4404, Nydalen, N-0403 Oslo, Norway; School of Pharmacy, University of Oslo, P.O. Box 1068, Blindern, 0316 Oslo, Norway.
| | - Sara Bremer
- Department of Medical Biochemistry, Oslo University Hospital Rikshospitalet, P.O. Box 4950, N-0424 Oslo, Norway.
| | - Inger Lise Bogen
- Division of Forensic Sciences, Norwegian Institute of Public Health (NIPH), P.O. Box 4404, Nydalen, N-0403 Oslo, Norway.
| | - Anna-Lena Zackrisson
- National Board of Forensic Medicine, Department of Forensic Genetics and Forensic Toxicology, Artillerigatan 12, SE-58758 Linkøping, Sweden.
| | - Marianne Arnestad
- Division of Forensic Sciences, Norwegian Institute of Public Health (NIPH), P.O. Box 4404, Nydalen, N-0403 Oslo, Norway; Center for Psychopharmacology, Diakonhjemmet Hospital, Oslo, Norway.
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16
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Li J, Xie M, Wang X, Ouyang X, Wan Y, Dong G, Yang Z, Yang J, Yue J. Sex hormones regulate cerebral drug metabolism via brain miRNAs: down-regulation of brain CYP2D by androgens reduces the analgesic effects of tramadol. Br J Pharmacol 2015; 172:4639-54. [PMID: 26031356 DOI: 10.1111/bph.13206] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 05/13/2015] [Accepted: 05/21/2015] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE Brain cytochrome P450 2D (CYP2D) metabolises exogenous neurotoxins, endogenous substances and neurotransmitters. Brain CYP2D can be regulated in an organ-specific manner, but the possible regulatory mechanisms are poorly understood. We investigated the involvement of miRNAs in the selective regulation of brain CYP2D by testosterone and the corresponding alteration of the pharmacological profiles of tramadol by testosterone. EXPERIMENTAL APPROACH The regulation of CYP2D and brain-enriched miRNAs by testosterone was investigated using SH-SY5Y cells, U251 cells, and HepG2 cells as well as orchiectomized growth hormone receptor knockout (GHR-KO) mice and rats. Concentration-time curves of tramadol in rat brain were determined using a microdialysis technique. The analgesic action of tramadol was assessed by the tail-flick test in rats. KEY RESULTS miR-101 and miR-128-2 bound the 3'-untranslated region of the CYP2D6 mRNA and decreased its level. Testosterone decreased CYP2D6 catalytic function via the up-regulation of miR-101 and miR-128-2 in SH-SY5Y and U251 cells, but not in HepG2 cells. Orchiectomy decreased the levels of miR-101 and miR-128-2 in the hippocampus of male GHR-KO mice, indicating that androgens regulate miRNAs directly, not via the alteration of growth hormone secretion patterns. Changes in the pharmacokinetic and pharmacodynamic profiles of tramadol by orchiectomy was attenuated by either testosterone supplementation or a specific brain CYP2D inhibitor. CONCLUSIONS AND IMPLICATIONS The selective regulation of brain CYP2D via brain-enriched miRNAs, following changes in androgen levels, such as in testosterone therapy, androgen deprivation therapy and/or ageing may alter the response to centrally active substances.
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Affiliation(s)
- Jie Li
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, China
| | - Mengmeng Xie
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, China
| | - Xiaoshuang Wang
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, China
| | - Xiufang Ouyang
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, China
| | - Yu Wan
- Department of Physiology, Wuhan University School of Basic Medical Sciences, Wuhan, China
| | - Guicheng Dong
- Baotou Teachers' College, Inner Mongolia University of Science and Technology, Baotou, China
| | - Zheqiong Yang
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, China
| | - Jing Yang
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, China
| | - Jiang Yue
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, China
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Ingelman-Sundberg M, Persson A, Jukic MM. Polymorphic expression of CYP2C19 and CYP2D6 in the developing and adult human brain causing variability in cognition, risk for depression and suicide: the search for the endogenous substrates. Pharmacogenomics 2015; 15:1841-4. [PMID: 25495406 DOI: 10.2217/pgs.14.151] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Affiliation(s)
- Magnus Ingelman-Sundberg
- Department of Physiology & Pharmacology, Section of Pharmacogenetics, Karolinska Institutet, SE-17177 Stockholm, Sweden
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18
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Ford KA, Ryslik G, Sodhi J, Halladay J, Diaz D, Dambach D, Masuda M. Computational predictions of the site of metabolism of cytochrome P450 2D6 substrates: comparative analysis, molecular docking, bioactivation and toxicological implications. Drug Metab Rev 2015; 47:291-319. [DOI: 10.3109/03602532.2015.1047026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Sosa-Macias M, Moya GE, LLerena A, Ramírez R, Terán E, Peñas-LLedó EM, Tarazona-Santos E, Galaviz-Hernández C, Céspedes-Garro C, Acosta H. Population pharmacogenetics of Ibero-Latinoamerican populations (MESTIFAR 2014). Pharmacogenomics 2015; 16:673-6. [PMID: 25929854 DOI: 10.2217/pgs.15.32] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
MESTIFAR 2014 28-30 November 2014, Panama City, Panama The CEIBA consortium was created within the Ibero-American network of Pharmacogenetics (RIBEF) to study population pharmacogenetics. The current status of these initiatives and results of the MESTIFAR project were analyzed in Panama, 28-30 November 2014. The MESTIFAR project focused on studying CYPs genetic polymorphisms in populations of different ethnic origin. So far, more than 6000 healthy volunteers have been evaluated, making this one of the largest population pharmacogenomic studies worldwide. Three symposia were organized, 'Pharmacogenetics of indigenous and mestizos populations and its clinical implications', 'Methodological innovation in pharmacogenetics and its application in health', and 'General discussion and concluding remarks', about mechanisms and proposals for training, diffusion of pharmacogenetics for Spanish- and Portuguese-speaking health professionals, and 'bench to bedside' pilot projects.
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Affiliation(s)
| | | | | | - Ronald Ramírez
- 5UNAN-León, Universidad Nacional Autónoma de Nicaragua, León, Nicaragua
| | - Enrique Terán
- 6USFQ, Colegio de Ciencias de la Salud, Universidad San Francisco de Quito, Quito, Ecuador
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20
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Blasco-Fontecilla H, Peñas-Lledó E, Vaquero-Lorenzo C, Dorado P, Saiz-Ruiz J, Llerena A, Baca-García E. CYP2D6 polymorphism and mental and personality disorders in suicide attempters. J Pers Disord 2014; 28:873-83. [PMID: 25437930 DOI: 10.1521/pedi_2012_26_080] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Prior studies on the association between the CYP2D6 polymorphism and suicide did not explore whether mental and personality disorders mediate this association. The main objective of the present study was to test an association between CYP2D6 polymorphism and mental and personality disorders among suicide attempters. The MINI and the DSM-IV version of the International Personality Disorder Examination Screening Questionnaire were used to diagnose mental and personality disorders, respectively, in 342 suicide attempters. Suicide attempters were divided into four groups according to their number of CYP2D6 active genes (zero, one, and two or more). Differences in mental and personality disorders across the four groups were measured using linear-by-linear association, chi square-test, and 95% confidence intervals. Suicide attempters carrying two or more active CYP2D6 genes were more likely to be diagnosed with at least one personality disorder than those with one or zero CYP2D6 active genes.
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21
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LLerena A, Naranjo MEG, Rodrigues-Soares F, Penas-LLedó EM, Fariñas H, Tarazona-Santos E. Interethnic variability ofCYP2D6alleles and of predicted and measured metabolic phenotypes across world populations. Expert Opin Drug Metab Toxicol 2014; 10:1569-83. [DOI: 10.1517/17425255.2014.964204] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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22
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Fernández-Aranda F, Sauchelli S, Pastor A, Gonzalez ML, de la Torre R, Granero R, Jiménez-Murcia S, Baños R, Botella C, Fernández-Real JM, Fernández-García JC, Frühbeck G, Gómez-Ambrosi J, Rodríguez R, Tinahones FJ, Arcelus J, Fagundo AB, Agüera Z, Miró J, Casanueva FF. Moderate-vigorous physical activity across body mass index in females: moderating effect of endocannabinoids and temperament. PLoS One 2014; 9:e104534. [PMID: 25101961 PMCID: PMC4125187 DOI: 10.1371/journal.pone.0104534] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 07/10/2014] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Endocannabinoids and temperament traits have been linked to both physical activity and body mass index (BMI) however no study has explored how these factors interact in females. The aims of this cross-sectional study were to 1) examine differences among distinct BMI groups on daytime physical activity and time spent in moderate-vigorous physical activity (MVPA), temperament traits and plasma endocannabinoid concentrations; and 2) explore the association and interaction between MVPA, temperament, endocannabinoids and BMI. METHODS Physical activity was measured with the wrist-worn accelerometer Actiwatch AW7, in a sample of 189 female participants (43 morbid obese, 30 obese, and 116 healthy-weight controls). The Temperament and Character Inventory-Revised questionnaire was used to assess personality traits. BMI was calculated by bioelectrical impedance analysis via the TANITA digital scale. Blood analyses were conducted to measure levels of endocannabinoids and endocannabinoid-related compounds. Path-analysis was performed to examine the association between predictive variables and MVPA. RESULTS Obese groups showed lower MVPA and dysfunctional temperament traits compared to healthy-weight controls. Plasma concentrations of 2-arachidonoylglyceryl (2-AG) were greater in obese groups. Path-analysis identified a direct effect between greater MVPA and low BMI (b = -0.13, p = .039) and high MVPA levels were associated with elevated anandamide (AEA) levels (b = 0.16, p = .049) and N-oleylethanolamide (OEA) levels (b = 0.22, p = .004), as well as high Novelty seeking (b = 0.18, p<.001) and low Harm avoidance (b = -0.16, p<.001). CONCLUSIONS Obese individuals showed a distinct temperament profile and circulating endocannabinoids compared to controls. Temperament and endocannabinoids may act as moderators of the low MVPA in obesity.
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Affiliation(s)
- Fernando Fernández-Aranda
- Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Clinical Sciences, School of Medicine, University of Barcelona, Barcelona, Spain
- * E-mail: (FF-A); (FFC)
| | - Sarah Sauchelli
- Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain
| | - Antoni Pastor
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Pharmacology, School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
- Human Pharmacology and Clinical Neurosciences Research Group, Neuroscience Research Program, IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
| | | | - Rafael de la Torre
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Human Pharmacology and Clinical Neurosciences Research Group, Neuroscience Research Program, IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Roser Granero
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Departament de Psicobiologia i Metodologia, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Susana Jiménez-Murcia
- Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Clinical Sciences, School of Medicine, University of Barcelona, Barcelona, Spain
| | - Rosa Baños
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Psychological, Personality, Evaluation and Treatment of the University of Valencia, Valencia, Spain
| | - Cristina Botella
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Basic Psychology, Clinic and Psychobiology of the University Jaume I, Castelló, Spain
| | - Jose M. Fernández-Real
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Diabetes, Endocrinology and Nutrition, Institut d’Investigació Biomèdica de Girona (IdlBGi) Hospital Dr Josep Trueta, Girona, Spain
| | - Jose C. Fernández-García
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Diabetes, Endocrinology and Nutrition, Hospital Clínico Universitario Virgen de Victoria, Málaga, Spain
| | - Gema Frühbeck
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Endocrinology and Nutrition, Clínica Universidad de Navarra, University of Navarra, Pamplona, Spain
| | - Javier Gómez-Ambrosi
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Endocrinology and Nutrition, Clínica Universidad de Navarra, University of Navarra, Pamplona, Spain
| | - Roser Rodríguez
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Diabetes, Endocrinology and Nutrition, Institut d’Investigació Biomèdica de Girona (IdlBGi) Hospital Dr Josep Trueta, Girona, Spain
| | - Francisco J. Tinahones
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Diabetes, Endocrinology and Nutrition, Hospital Clínico Universitario Virgen de Victoria, Málaga, Spain
| | - Jon Arcelus
- Eating Disorders Service, Glenfield University Hospital, Leicester, United Kingdom
| | - Ana B. Fagundo
- Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
| | - Zaida Agüera
- Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
| | - Jordi Miró
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Felipe F. Casanueva
- CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto Salud Carlos III, Madrid, Spain
- Department of Medicine, Endocrinology Division, Santiago de Compostela University, Complejo Hospitalario Universitario, Santiago de Compostela, Spain
- * E-mail: (FF-A); (FFC)
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23
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Miller RT, Miksys S, Hoffmann E, Tyndale RF. Ethanol self-administration and nicotine treatment increase brain levels of CYP2D in African green monkeys. Br J Pharmacol 2014; 171:3077-88. [PMID: 24611668 PMCID: PMC4055207 DOI: 10.1111/bph.12652] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 01/31/2014] [Accepted: 02/09/2014] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND AND PURPOSE CYP2D6 metabolizes many centrally acting drugs, neurotoxins and endogenous neurochemicals, and differences in brain levels of CYP2D have been associated with brain function and drug response. Alcohol consumers and smokers have higher levels of CYP2D6 in brain, but not liver, suggesting ethanol and/or nicotine may induce human brain CYP2D6. We investigated the independent and combined effects of chronic ethanol self-administration and nicotine treatment on CYP2D expression in African green monkeys. EXPERIMENTAL APPROACH Forty monkeys were randomized into control, ethanol-only, nicotine-only and ethanol + nicotine groups. Two groups voluntarily self-administered 10% ethanol in sucrose solution for 4 h·day(-1) , whereas two groups consumed sucrose solution on the same schedule. Two groups received daily s.c. injections of 0.5 mg·kg(-1) nicotine in saline bid, whereas two groups were injected with saline on the same schedule. KEY RESULTS Both nicotine and ethanol dose-dependently increased CYP2D in brain; brain mRNA was unaffected, and neither drug altered hepatic CYP2D protein or mRNA. The combination of ethanol and nicotine increased brain CYP2D protein levels to a greater extent than either drug alone (1.2-2.2-fold, P < 0.05 among the eight brain regions assessed). Immunohistochemistry revealed the induction of brain CYP2D protein within specific cell types and regions in the treatment groups. CONCLUSIONS AND IMPLICATIONS Ethanol and nicotine increase brain CYP2D protein levels in monkeys, in a region and treatment-specific manner, suggesting that CNS drug responses, neurodegeneration and personality may be affected among people who consume alcohol and/or nicotine.
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Affiliation(s)
- R T Miller
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health and Departments of Psychiatry, Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
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24
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Peñas-LLedó EM, LLerena A. CYP2D6 variation, behaviour and psychopathology: implications for pharmacogenomics-guided clinical trials. Br J Clin Pharmacol 2014; 77:673-83. [PMID: 24033670 PMCID: PMC3971983 DOI: 10.1111/bcp.12227] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Accepted: 08/11/2013] [Indexed: 12/16/2022] Open
Abstract
Individual and population differences in polymorphic cytochrome P450 enzyme function have been known for decades. The biological significance of these differences has now been deciphered with regard to drug metabolism, action and toxicity as well as disposition of endogenous substrates, including neuroactive compounds. While the cytochrome P450 enzymes occur abundantly in the liver, they are expressed in most tissues of the body, albeit in varying amounts, including the brain. The latter location of cytochrome P450s is highly pertinent for susceptibility to neuropsychiatric diseases, not to mention local drug metabolism at the site of psychotropic drug action in the brain. In the current era of personality medicine with companion theranostics (i.e. the fusion of therapeutics with diagnostics), this article underscores that such versatile biological roles of cytochrome P450s offer multiple points of entry for personalized medicine and rational therapeutics. We focus our discussion on CYP2D6, one of the most intensively researched drug and endogenous compound metabolism pathways, with a view to relevance for, and optimization of, pharmacogenomic-guided clinical trials. Working on the premise that CYP2D6 is related to human behaviour and certain personality traits such as serotonin and dopamine system function, we further suggest that the motivation of healthy volunteers to participate in clinical trials may in part be influenced by an under- or over-representation of certain CYP2D6 metabolic groups.
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Affiliation(s)
- Eva M Peñas-LLedó
- CICAB Clinical Research Centre, Extremadura University Hospital and Medical SchoolBadajoz
| | - Adrián LLerena
- CICAB Clinical Research Centre, Extremadura University Hospital and Medical SchoolBadajoz
- CIBERSAM, ISCIIIMadrid, Spain
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25
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Wang X, Li J, Dong G, Yue J. The endogenous substrates of brain CYP2D. Eur J Pharmacol 2013; 724:211-8. [PMID: 24374199 DOI: 10.1016/j.ejphar.2013.12.025] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 12/17/2013] [Accepted: 12/17/2013] [Indexed: 12/19/2022]
Abstract
CYP2D6, one of the major cytochrome P450 isoforms present in the human brain, is associated with the incidence and prevalence of central nervous system (CNS) diseases. Human CYP2D6 and rat CYP2D are involved in the metabolism of various neurotransmitters and neurosteroids. Brain CYP2D can be regulated by endogenous steroids, including sex hormones. The alteration of CYP2D-mediated metabolism induced by endogenous steroids may cause changes in sensitivity to environmental and industrial toxins and carcinogens as well as physiological and pathophysiological processes controlled by biologically active compounds. This review summarizes the current knowledge regarding the distribution, endogenous substrates, and regulation of brain CYP2D.
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Affiliation(s)
- Xiaoshuang Wang
- Department of Pharmacology, School of Medical Sciences, Wuhan University, No. 185 East Lake Road, Wuhan 430071, China; Department of Pharmacy, Wuhan Puren Hospital, Wuhan 430081, China
| | - Jie Li
- Department of Pharmacology, School of Medical Sciences, Wuhan University, No. 185 East Lake Road, Wuhan 430071, China
| | - Guicheng Dong
- Baotou Teachers' College, Inner Mongolia University of Science & Technology, Baotou 014030, China
| | - Jiang Yue
- Department of Pharmacology, School of Medical Sciences, Wuhan University, No. 185 East Lake Road, Wuhan 430071, China.
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26
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LLerena A, Dorado P, Ramírez R, Calzadilla LR, Peñas-LLedó E, Álvarez M, Naranjo MEG, González I, Pérez B. CYP2D6 -1584C>G promoter polymorphism and debrisoquine ultrarapid hydroxylation in healthy volunteers. Pharmacogenomics 2013; 14:1973-7. [DOI: 10.2217/pgs.13.181] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Background & aim: The CYP2D6 -1584C>G polymorphism (rs1080985) has been identified as a major factor for CYP2D6 expression and function, with the mutant -1584G promoter type being consistently associated with significantly greater expression than -1584C. It may therefore be associated with ultrarapid metabolism. The objective of the present study was to explore the relationship between the CYP2D6 -1584C>G polymorphism and the debrisoquine metabolic ratio in healthy volunteers in order to evaluate its potential impact on the ultrarapid CYP2D6 hydroxylation capacity. Materials & methods: The CYP2D6 -1584C>G polymorphism was analyzed in 320 unrelated healthy individuals who were previously phenotyped for debrisoquine hydroxylation. Results: The metabolic ratio (log10 mean ± standard deviation) of individuals with the -1584G allele was lower than that of individuals with the -1584C allele for carriers of one active CYP2D6 gene (-0.13 ± 0.33 and 0.17 ± 0.52, respectively; p < 0.05) or two active CYP2D6 genes (-0.32 ± 0.39 and -0.20 ± 0.44, respectively; p < 0.05). Conclusion: The presence of the -1584G allele in the promoter region of the CYP2D6 gene was related to a high CYP2D6 hydroxylation capacity. Original submitted 3 June 2013; Revision submitted 11 September 2013
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Affiliation(s)
| | - Pedro Dorado
- CICAB Clinical Research Centre, Extremadura University Hospital & Medical School, Badajoz 06080, Spain
| | | | | | - Eva Peñas-LLedó
- CICAB Clinical Research Centre, Extremadura University Hospital & Medical School, Badajoz 06080, Spain
| | - Mayra Álvarez
- Facultad de Ciencias Médicas "Gral Calixto García", La Habana, Cuba
| | - María EG Naranjo
- CICAB Clinical Research Centre, Extremadura University Hospital & Medical School, Badajoz 06080, Spain
| | - Idilio González
- Hospital de Llerena, Servicio Extremeño de Salud, Llerena, Spain
| | - Bárbaro Pérez
- Facultad de Ciencias Médicas "Gral Calixto García", La Habana, Cuba
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Abstract
Cytochrome P450 enzymes (CYPs) metabolize many drugs that act on the central nervous system (CNS), such as antidepressants and antipsychotics; drugs of abuse; endogenous neurochemicals, such as serotonin and dopamine; neurotoxins; and carcinogens. This takes place primarily in the liver, but metabolism can also occur in extrahepatic organs, including the brain. This is important for CNS-acting drugs, as variation in brain CYP-mediated metabolism may be a contributing factor when plasma levels do not predict drug response. This review summarizes the characterization of CYPs in the brain, using examples from the CYP2 subfamily, and discusses sources of variation in brain CYP levels and metabolism. Some recent experiments are described that demonstrate how changes in brain CYP metabolism can influence drug response, toxicity and drug-induced behaviours. Advancing knowledge of brain CYP-mediated metabolism may help us understand why patients respond differently to drugs used in psychiatry and predict risk for psychiatric disorders, including neurodegenerative diseases and substance abuse.
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Affiliation(s)
| | - Rachel F. Tyndale
- Correspondence to: R.F. Tyndale, Department of Pharmacology and Toxicology, 1 King’s College Circle, Toronto ON M5S 1A8;
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Genetic variability of drug-metabolizing enzymes: the dual impact on psychiatric therapy and regulation of brain function. Mol Psychiatry 2013; 18:273-87. [PMID: 22565785 DOI: 10.1038/mp.2012.42] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Polymorphic drug-metabolizing enzymes (DMEs) are responsible for the metabolism of the majority of psychotropic drugs. By explaining a large portion of variability in individual drug metabolism, pharmacogenetics offers a diagnostic tool in the burgeoning era of personalized medicine. This review updates existing evidence on the influence of pharmacogenetic variants on drug exposure and discusses the rationale for genetic testing in the clinical context. Dose adjustments based on pharmacogenetic knowledge are the first step to translate pharmacogenetics into clinical practice. However, also clinical factors, such as the consequences on toxicity and therapeutic failure, must be considered to provide clinical recommendations and assess the cost-effectiveness of pharmacogenetic treatment strategies. DME polymorphisms are relevant not only for clinical pharmacology and practice but also for research in psychiatry and neuroscience. Several DMEs, above all the cytochrome P (CYP) enzymes, are expressed in the brain, where they may contribute to the local biochemical homeostasis. Of particular interest is the possibility of DMEs playing a physiological role through their action on endogenous substrates, which may underlie the reported associations between genetic polymorphisms and cognitive function, personality and vulnerability to mental disorders. Neuroimaging studies have recently presented evidence of an effect of the CYP2D6 polymorphism on basic brain function. This review summarizes evidence on the effect of DME polymorphisms on brain function that adds to the well-known effects of DME polymorphisms on pharmacokinetics in explaining the range of phenotypes that are relevant to psychiatric practice.
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Villagra D, Goethe J, Schwartz HI, Szarek B, Kocherla M, Gorowski K, Windemuth A, Ruaño G. Novel drug metabolism indices for pharmacogenetic functional status based on combinatory genotyping of CYP2C9, CYP2C19 and CYP2D6 genes. Biomark Med 2012; 5:427-38. [PMID: 21861665 DOI: 10.2217/bmm.11.32] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIMS We aim to demonstrate clinical relevance and utility of four novel drug-metabolism indices derived from a combinatory (multigene) approach to CYP2C9, CYP2C19 and CYP2D6 allele scoring. Each index considers all three genes as complementary components of a liver enzyme drug metabolism system and uniquely benchmarks innate hepatic drug metabolism reserve or alteration through CYP450 combinatory genotype scores. METHODS A total of 1199 psychiatric referrals were genotyped for polymorphisms in the CYP2C9, CYP2C19 and CYP2D6 gene loci and were scored on each of the four indices. The data were used to create distributions and rankings of innate drug metabolism capacity to which individuals can be compared. Drug-specific indices are a combination of the drug metabolism indices with substrate-specific coefficients. RESULTS The combinatory drug metabolism indices proved useful in positioning individuals relative to a population with regard to innate drug metabolism capacity prior to pharmacotherapy. Drug-specific indices generate pharmacogenetic guidance of immediate clinical relevance, and can be further modified to incorporate covariates in particular clinical cases. CONCLUSIONS We believe that this combinatory approach represents an improvement over the current gene-by-gene reporting by providing greater scope while still allowing for the resolution of a single-gene index when needed. This method will result in novel clinical and research applications, facilitating the translation from pharmacogenomics to personalized medicine, particularly in psychiatry where many drugs are metabolized or activated by multiple CYP450 isoenzymes.
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The prototypic pharmacogenetic drug debrisoquine is a substrate of the genetically polymorphic organic cation transporter OCT1. Biochem Pharmacol 2012; 83:1427-34. [PMID: 22342776 DOI: 10.1016/j.bcp.2012.01.032] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 01/27/2012] [Accepted: 01/27/2012] [Indexed: 11/22/2022]
Abstract
Debrisoquine is a probe drug for in vivo phenotyping of human CYP2D6 metabolic activity. However, debrisoquine is positively charged under physiological conditions and it is unclear how it enters the hepatocytes to undergo CYP2D6 metabolism. We analysed whether debrisoquine is a substrate of the hepatic organic cation transporter OCT1 and whether drug-drug interactions at OCT1, or polymorphisms in OCT1 gene, affect debrisoquine uptake. Debrisoquine showed low carrier-independent membrane permeability (P(e) of 0.01×10⁻⁶ cm/s in artificial PAMPA membranes) and strongly inhibited the uptake of the model OCT1 substrate MPP+ (IC₅₀ of 6.2 ± 0.8 μM). Debrisoquine uptake was significantly increased in HEK293 cells overexpressing OCT1 compared to control cells. The OCT1-mediated uptake of debrisoquine followed Michaelis-Menten kinetics (K(M) of 5.9 ± 1.5 μM and V(max) of 41.9 ± 4.5pmol/min/mg protein) and was inhibited by known OCT1 inhibitors and by commonly used drugs. OCT1-mediated debrisoquine uptake was reduced or missing in cells expressing loss-of-function OCT1 isoforms. Deletion of Met420 or substitution of Arg61Cys or Gly401Ser reduced V(max) by 48, 63 and 91%, respectively, but did not affect the K(M). The OCT1 isoforms carrying Cys88Arg or Gly465Arg substitutions completely lacked OCT1-mediated debrisoquine uptake. In conclusion, debrisoquine is a substrate of OCT1 and has the potential to be used as a phenotyping marker for OCT1 activity. Moreover, variations in debrisoquine metabolic phenotypes and their associations with diseases may be due not only to genetic variations CYP2D6, but also in OCT1.
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Stingl JC, Esslinger C, Tost H, Bilek E, Kirsch P, Ohmle B, Viviani R, Walter H, Rietschel M, Meyer-Lindenberg A. Genetic variation in CYP2D6 impacts neural activation during cognitive tasks in humans. Neuroimage 2012; 59:2818-23. [DOI: 10.1016/j.neuroimage.2011.07.052] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 07/11/2011] [Accepted: 07/18/2011] [Indexed: 02/03/2023] Open
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Peñas-Lledó EM, Blasco-Fontecilla H, Dorado P, Vaquero-Lorenzo C, Baca-García E, Llerena A. CYP2D6 and the severity of suicide attempts. Pharmacogenomics 2012; 13:179-84. [DOI: 10.2217/pgs.11.146] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: Among people who die by suicide, an increased frequency of CYP2D6 active gene multiplication has been described. Therefore, the present study analyzed the relationship between the severity of the suicidal intent and CYP2D6 number of active genes among survivors. Materials & methods: A group of 342 individuals were evaluated with Beck Suicide Intent Scale within 24 h of the failed attempt. ‘Severe’ suicide attempters were classified as those scoring above percentile 75 in the objective circumstances section of the Suicide Intent Scale Scale. A group of 377 healthy controls were also genotyped. Results: A higher number of ‘severe’ suicide attempters carrying ≥2 active CYP2D6 genes as compared with the rest of the patients population (p < 0.01) or the healthy control group (p < 0.01) was found. Conclusion: Considering that ‘severe’ suicide attempters are more likely eventually to die by suicide, CYP2D6 genetic polymorphism might be of use as a biomarker of death by suicide, which is in agreement with previous findings. Original submitted: 17 July 2011; Revision submitted: 21 September 2011
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Affiliation(s)
- Eva M Peñas-Lledó
- CICAB, Clinical Research Centre, Extremadura University Hospital & Medical School, Badajoz, Spain
| | - Hilario Blasco-Fontecilla
- Department of Psychiatry at Fundación Jimenez Diaz Hospital, Autónoma University, Madrid, Spain
- Centro de Investigación Biomedica en Red en el Área de Salud Mental (CIBERSAM), Madrid, Spain
| | - Pedro Dorado
- CICAB, Clinical Research Centre, Extremadura University Hospital & Medical School, Badajoz, Spain
| | - Concepción Vaquero-Lorenzo
- Department of Psychiatry at Fundación Jimenez Diaz Hospital, Autónoma University, Madrid, Spain
- Biology Department, Sciences Faculty-Autónoma University (UAM), Madrid, Spain
| | - Enrique Baca-García
- Department of Psychiatry at Fundación Jimenez Diaz Hospital, Autónoma University, Madrid, Spain
- Centro de Investigación Biomedica en Red en el Área de Salud Mental (CIBERSAM), Madrid, Spain
- Department of Psychiatry at the New York State Psychiatric Institute, Columbia University, New York, NY, USA
| | - Adrián Llerena
- CIS Faculdade de Ciências da Saúde, Universidade da Beira Interior, Covilhã, Portugal
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Teh LK, Bertilsson L. Pharmacogenomics of CYP2D6: molecular genetics, interethnic differences and clinical importance. Drug Metab Pharmacokinet 2011; 27:55-67. [PMID: 22185816 DOI: 10.2133/dmpk.dmpk-11-rv-121] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
CYP2D6 has received intense attention since the beginning of the pharmacogenetic era in the 1970s. This is because of its involvement in the metabolism of more than 25% of the marketed drugs, the large geographical and inter-ethnic differences in the genetic polymorphism and possible drug-induced toxicity. Many interesting reviews have been published on CYP2D6 and this review aims to reinstate the importance of the genetic polymorphism of CYP2D6 in different populations as well as some clinical implications and important drug interactions.
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Affiliation(s)
- Lay Kek Teh
- Pharmacogenomics Centre PROMISE, Faculty of Pharmacy, Universiti Teknologi MARA, Selangor DE, Malaysia.
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Dorado P, Heras N, Machín E, Hernández F, Teran E, LLerena A. CYP2D6 genotype and dextromethorphan hydroxylation phenotype in an Ecuadorian population. Eur J Clin Pharmacol 2011; 68:637-44. [DOI: 10.1007/s00228-011-1147-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 10/14/2011] [Indexed: 11/29/2022]
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Landino J, Buckley J, Roy JM, Villagra D, Gorowski K, Kocherla M, Windemuth A, Ruaño G. Guidance of pharmacotherapy in a complex psychiatric case by CYP450 DNA typing. ACTA ACUST UNITED AC 2011; 23:459-63. [DOI: 10.1111/j.1745-7599.2011.00640.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Bromek E, Haduch A, Gołembiowska K, Daniel WA. Cytochrome P450 mediates dopamine formation in the brain in vivo. J Neurochem 2011; 118:806-15. [PMID: 21651557 DOI: 10.1111/j.1471-4159.2011.07339.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The cytochrome P450-mediated synthesis of dopamine from tyramine has been shown in vitro. The aim of the present study was to demonstrate the ability of rat cytochrome P450 (CYP) 2D to synthesize dopamine from tyramine in the brain in vivo. We employed two experimental models using reserpinized rats with a blockade of the classical pathway of dopamine synthesis from tyrosine. Model A estimated dopamine production from endogenous tyramine in brain structures in vivo (ex vivo measurement of a tissue dopamine level), while Model B measured extracellular dopamine produced from exogenous tyramine (an in vivo microdialysis). In Model A, quinine (a CYP2D inhibitor) given intraperitoneally caused a significant decrease in dopamine level in the striatum and nucleus accumbens and tended to fall in the substantia nigra and frontal cortex. In Model B, an increase in extracellular dopamine level was observed after tyramine given intrastructurally (the striatum). After joint administration of tyramine and quinine, the amount of the dopamine formed was significantly lower compared to the group receiving tyramine only. The results of the two complementary experimental models indicate that the hydroxylation of tyramine to dopamine may take place in rat brain in vivo, and that CYP2D catalyzes this reaction.
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Affiliation(s)
- Ewa Bromek
- Polish Academy of Sciences, Institute of Pharmacology, Kraków, Poland
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Kirchheiner J, Seeringer A, Godoy AL, Ohmle B, Maier C, Beschoner P, Sim EJ, Viviani R. CYP2D6 in the brain: genotype effects on resting brain perfusion. Mol Psychiatry 2011; 16:237, 333-41. [PMID: 20368706 DOI: 10.1038/mp.2010.42] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The cytochrome P450 2D6 (CYP2D6) is a genetically polymorphic enzyme involved in the metabolism of several psychoactive drugs. Beside its expression in the liver, CYP2D6 is highly expressed in several regions of the brain, such as the hippocampus, thalamus, hypothalamus and the cortex, but its function in the brain is not well understood. The CYP2D6 enzyme may also have a physiological role due to its involvement in neurotransmitter biotransformation. In this study, CYP2D6 genotyping was performed in N=188 healthy individuals and compared with brain perfusion levels at rest, which may reflect an ongoing biological process regulating the reactivity of the individual to emotional stimuli and the detection of signals evoking fear. Relative to N=42 matched extensive metabolizers, N=14 poor metabolizers were associated with 15% higher perfusion levels in the thalamus (P=0.03 and 0.003). Effects were also present in the whole (N=188) sample divided into metabolizer groups, or finely graded into seven CYP2D6 activity levels. A weaker effect was observed in the right hippocampus (P=0.05). An exploratory analysis, extended to the whole brain, suggested the involvement of CYP2D6 in regions associated with alertness or serotonergic function. These findings support the hypothesis of a functional role of CYP2D6 in the brain.
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Affiliation(s)
- J Kirchheiner
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, University of Ulm, Ulm, Germany.
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Wong EHF, Fox JC, Ng MYM, Lee CM. Toward personalized medicine in the neuropsychiatric field. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2011; 101:329-49. [PMID: 22050858 DOI: 10.1016/b978-0-12-387718-5.00013-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
There are great expectations for the personalized medicine approach to address the therapeutic needs of patients in the twenty-first century. Advances in human genome science and molecular innovations in neuroscience have encouraged the pharmaceutical industry to focus beyond broad spectrum population therapeutics--the driving force behind the "blockbuster" product concept--to personalized medicine. For central nervous system (CNS) therapeutics, repeated failures in converting scientific discoveries to clinical trial successes and regulatory approvals have precipitated a drug pipeline crisis and eroded confidence in the industry. This chapter describes how innovations in genomics and translational medicine can impact the future of neuropsychiatry and deconvolute the complexity of psychiatric diseases from symptoms biology. A targeted and consistent investment is needed to restore confidence in translating science into clinical success.
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Affiliation(s)
- Erik H F Wong
- AstraZeneca Pharmaceuticals, External Science, CNS-Pain Innovative Medicine Unit, Wilmington, Delaware, USA
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CYP2D6 genotype and debrisoquine hydroxylation phenotype in Cubans and Nicaraguans. THE PHARMACOGENOMICS JOURNAL 2010; 12:176-83. [DOI: 10.1038/tpj.2010.85] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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40
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Gassó P, Mas S, Álvarez S, Trias G, Bioque M, Oliveira C, Bernardo M, Lafuente A. Xenobiotic metabolizing and transporter genes: gene–gene interactions in schizophrenia and related disorders. Pharmacogenomics 2010; 11:1725-31. [DOI: 10.2217/pgs.10.158] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Aims: In this study we explored possible epistasis between CYP2D6 (*3, *4, *5, *6 and *1xN), CYP3A5 (*3), CYP1A2 (*1C and *1F) and ABCB1 (G2677T) in schizophrenia and related disorders. Materials & methods: A total of 344 patients diagnosed with schizophrenia and related disorders, and 484 healthy controls participated in the present study. We analyzed gene–gene interactions by multifactor dimensionality reduction. Results: A four-way model including ABCB1 G2677T, CYP3A5*3, CYP1A2*1F and CYP2D6*4 variants had the best overall performances (accuracy: 0.573) and a crossvalidation consistency of 10/10 (permutation testing p < 0.004). Conclusion: Our results suggest a significant involvement of CYPs and transporters in brain metabolism and homeostasis, and provide evidence of gene–gene interactions among xenobiotic metabolizing and transporter genes in the context of schizophrenia.
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Affiliation(s)
- Patricia Gassó
- Department of Anatomic Pathology, Pharmacology & Microbiology, University of Barcelona, Casanova 143, E-08036, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Sergi Mas
- Department of Anatomic Pathology, Pharmacology & Microbiology, University of Barcelona, Casanova 143, E-08036, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Santi Álvarez
- Department of Anatomic Pathology, Pharmacology & Microbiology, University of Barcelona, Casanova 143, E-08036, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Gemma Trias
- Department of Anatomic Pathology, Pharmacology & Microbiology, University of Barcelona, Casanova 143, E-08036, Barcelona, Spain
| | - Miquel Bioque
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
- Psychiatry Service, Hospital Clinic de Barcelona, Villarroel 170, E-08036 Barcelona, Spain
| | - Cristina Oliveira
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Psychiatry Service, Hospital Clinic de Barcelona, Villarroel 170, E-08036 Barcelona, Spain
| | - Miquel Bernardo
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
- Psychiatry Service, Hospital Clinic de Barcelona, Villarroel 170, E-08036 Barcelona, Spain
- Department Psychiatry & Clinical Psychobiology, University of Barcelona, Casanova 143, E-08036 Barcelona, Spain
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Prescribing patterns and the use of therapeutic drug monitoring of psychotropic medication in a psychiatric high-security unit. Ther Drug Monit 2010; 30:597-603. [PMID: 18708990 DOI: 10.1097/ftd.0b013e31818622c4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The aim of this study was to investigate the use of psychotropic medication and therapeutic drug monitoring in a high-security psychiatric unit and to compare the doses and serum concentrations both with the recommended intervals and with the doses and serum concentrations in a control group. One hundred thirty-two patients were admitted in the period from January 2000 to December 2005. All available samples were used when comparing serum concentrations and doses with the recommended ranges. For the comparison of doses and serum concentration-to-dose (C:D) ratios with the control group only 1 sample from each patient was used. A total of 459 analyses of 27 different drugs in samples from 8 women and 73 men were included. The median number of therapeutic drug monitoring analyses per patient was 4 (range 1-29). Thirty-seven of the 81 patients (46%) used 2 or more antipsychotics at the same time. Clozapine, lamotrigine, olanzapine, quetiapine, ziprasidone, and zuclopenthixol were often given in doses above the recommended. The serum levels were frequently above those recommended for clozapine, olanzapine, quetiapine, risperidone, ziprasidone, and zuclopenthixol. The serum levels were significantly higher in the study group than in the control group for clozapine, lamotrigine, quetiapine, and zuclopenthixol. The given dose was significantly higher in the study group than in the control group for clozapine, lamotrigine and zuclopenthixol. The C:D ratio was significantly lower in the study group than in the control group for olanzapine but higher for quetiapine. The non-evidence based practice of high-dose polypharmacy with several antipsychotics is widely used in this unit. The use of higher doses in the study group than in the control group was not due to differences in metabolism or adherence to treatment between the 2 groups. The frequent use of therapeutic drug monitoring did not seem to have a great impact on the prescribed doses.
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CYP2D6 polymorphism in patients with eating disorders. THE PHARMACOGENOMICS JOURNAL 2010; 12:173-5. [DOI: 10.1038/tpj.2010.78] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Snider NT, Walker VJ, Hollenberg PF. Oxidation of the endogenous cannabinoid arachidonoyl ethanolamide by the cytochrome P450 monooxygenases: physiological and pharmacological implications. Pharmacol Rev 2010; 62:136-54. [PMID: 20133390 DOI: 10.1124/pr.109.001081] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Arachidonoyl ethanolamide (anandamide) is an endogenous amide of arachidonic acid and an important signaling mediator of the endocannabinoid system. Given its numerous roles in maintaining normal physiological function and modulating pathophysiological responses throughout the body, the endocannabinoid system is an important pharmacological target amenable to manipulation directly by cannabinoid receptor ligands or indirectly by drugs that alter endocannabinoid synthesis and inactivation. The latter approach has the possible advantage of more selectivity, thus there is the potential for fewer untoward effects like those that are traditionally associated with cannabinoid receptor ligands. In that regard, inhibitors of the principal inactivating enzyme for anandamide, fatty acid amide hydrolase (FAAH), are currently in development for the treatment of pain and inflammation. However, several pathways involved in anandamide synthesis, metabolism, and inactivation all need to be taken into account when evaluating the effects of FAAH inhibitors and similar agents in preclinical models and assessing their clinical potential. Anandamide undergoes oxidation by several human cytochrome P450 (P450) enzymes, including CYP3A4, CYP4F2, CYP4X1, and the highly polymorphic CYP2D6, forming numerous structurally diverse lipids, which are likely to have important physiological roles, as evidenced by the demonstration that a P450-derived epoxide of anandamide is a potent agonist for the cannabinoid receptor 2. The focus of this review is to emphasize the need for a better understanding of the P450-mediated pathways of the metabolism of anandamide, because these are likely to be important in mediating endocannabinoid signaling as well as the pharmacological responses to endocannabinoid-targeting drugs.
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Affiliation(s)
- Natasha T Snider
- Department of Molecular & Integrative Physiology, University of Michigan School of Medicine, 7720 Medical Science II, 1301 E. Catherine Street, Ann Arbor, MI 48109-5622, USA.
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Bromek E, Haduch A, Daniel WA. The ability of cytochrome P450 2D isoforms to synthesize dopamine in the brain: An in vitro study. Eur J Pharmacol 2010; 626:171-8. [DOI: 10.1016/j.ejphar.2009.09.062] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 09/15/2009] [Accepted: 09/28/2009] [Indexed: 10/20/2022]
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Álvarez S, Mas S, Gassó P, Bernardo M, Parellada E, Lafuente A. Lack of association between schizophrenia and polymorphisms in dopamine metabolism and transport genes. Fundam Clin Pharmacol 2009; 24:741-7. [DOI: 10.1111/j.1472-8206.2009.00807.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Zackrisson AL, Lindblom B, Ahlner J. High frequency of occurrence of CYP2D6 gene duplication/multiduplication indicating ultrarapid metabolism among suicide cases. Clin Pharmacol Ther 2009; 88:354-9. [PMID: 19907421 DOI: 10.1038/clpt.2009.216] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In Sweden, about 550 individuals die every year of drug intoxication. Many of these drugs are metabolized by CYP enzymes such as CYP2D6 and CYP2C19. A lack of these enzymes, resulting in poor metabolism, can lead to adverse reactions and even to fatality. On the other hand, an ultrarapid metabolism can lead to insufficient drug plasma concentration, resulting in failure of treatment, or it can lead to high concentrations of active/toxic metabolites. The aim of this project was to study the genetic profile of individuals with regard to the presence of CYP2D6 and CYP2C19 genes, in cases of fatal intoxication (242), suicide (intoxications excluded) (262), and natural death (212). PCR, followed by pyrosequencing, was used for all the analyses. We found that, among those who died of suicide (suicide cases), there was a higher number carrying more than two active CYP2D6 genes (corresponding to the phenotype of ultrarapid metabolizer) as compared with those who died of natural causes (natural-death cases) (P = 0.007).
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Affiliation(s)
- A L Zackrisson
- Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden.
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Bijl MJ, Luijendijk HJ, van den Berg JF, Visser LE, van Schaik RHN, Hofman A, Vulto AG, van Gelder T, Tiemeier H, Stricker BHC. Association between the CYP2D6*4 polymorphism and depression or anxiety in the elderly. Pharmacogenomics 2009; 10:541-7. [PMID: 19374513 DOI: 10.2217/pgs.09.9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION 5-methoxytryptamine (5-MT), a precursor of serotonin, is considered to be an endogenous substrate of cytochrome P450 2D6 (CYP2D6). Homozygous carriers of the variant allele CYP2D6*4 lack CYP2D6 enzyme activity. Relative to extensive metabolizers, these poor metabolizers may have lower baseline serotonin concentrations in various brain regions, and may be more prone to depression or anxiety. AIM To test whether the CYP2D6*4/*4 genotype is associated with a predisposition to depression or anxiety disorders in the elderly. MATERIALS & METHODS We conducted a cross-sectional study within the Rotterdam Study, a population-based cohort study, among persons aged 55 years or older, who were screened for depression and anxiety disorders at two consecutive examination rounds. Logistic regression was used to analyze the association between the CYP2D6*4 polymorphism and the risk of depression or anxiety disorders. RESULTS The risk of major depression in CYP2D6*4/*4 was not significantly different from extensive metabolizers (OR = 0.85; 95% CI: 0.36-2.00; p = 0.72). Neither did we find an association between CYP2D6 genotype and minor depression (OR = 1.56; 95% CI: 0.69-3.52; p = 0.28). No increased risk of anxiety disorders was found (OR = 1.19; 95% CI: 0.68-2.09; p = 0.55). CONCLUSION Variation in the CYP2D6 gene is not related to a predisposition to depression or anxiety disorders in the elderly.
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Affiliation(s)
- Monique J Bijl
- Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
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Peñas-LLedó EM, Dorado P, Pacheco R, González I, LLerena A. Relation between CYP2D6 genotype, personality, neurocognition and overall psychopathology in healthy volunteers. Pharmacogenomics 2009; 10:1111-20. [DOI: 10.2217/pgs.09.75] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aims: A lower serotonin/higher dopamine tone in CYP2D6 poor metabolizers (PMs) versus extensive metabolizers (EMs) has been postulated, which is consistent with our prior research showing behavioral traits related to anxiety and impulsivity in PMs. This tone could also be related to PMs vulnerability to cognitive functioning and/or psychopathology. Therefore, the present study aimed to analyze the relationship between CYP2D6 genotype and personality, cognition and psychopathological vulnerability. The influence of affective state in these relationships was also analyzed. Materials & methods: A total of 144 healthy volunteers from the University of Extremadura (Spain) were evaluated by CYP2D6 genotypes, overall psychopathology (Symptom Checklist-90-revised [SCL-90-R]), personality (Karolinska Scales of Personality [KSP] and Temperament and Character Inventory [TCI-R]) and on cognitive functions with computerized CANTAB® tests. Results: PMs (n = 11) versus EMs (n = 133) (Mann–Whitney U-tests) presented higher ‘impulsivity’ in both KSP and TCI-R, and better performance of sustained attention (on the Rapid Visual Information Processing test) and lower overall psychopathology with all PMs scoring below 0.7 on SCL-90-R (‘positive affect’ group). There were differences between all participants scoring below (n = 107) and above (n = 37) 0.7 on SCL-90-R in most personality measures. Comparisons between PMs (n = 11) and EMs (n = 96) with SCL-90-R less than 0.7 maintained those results for KSP and CANTAB but also yielded greater scores on the TCI-R-‘perfectionism’ subscale in PMs. In multivariate analyses controlled for age, sex and psychopathology, KSP-impulsiveness, CANTAB-sustained attention, spatial working memory and paired associate learning were significantly different in PMs versus EMs. Conclusion: In the studied population of healthy volunteers, PMs versus EMs showed lower vulnerability to psychopathology and greater impulsivity. Moreover, differences in neurocognition were found. The cross-study reproducibility of the relationship between CYP2D6 and personality may be difficult due to the influence of psychopathology among other factors. The personality and cognitive factors found in PMs appear compatible with a low serotonin/high dopamine balance.
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Affiliation(s)
- Eva M Peñas-LLedó
- Clinical Research Centre (CICAB), Centro de Investigación Clínica, Área de Salud de Badajoz, SES Servicio Extremeño de Salud, Hospital Universitario Infanta Cristina, 06080 Badajoz, Spain
| | - Pedro Dorado
- Clinical Research Centre (CICAB), Centro de Investigación Clínica, Área de Salud de Badajoz, SES Servicio Extremeño de Salud, Hospital Universitario Infanta Cristina, 06080 Badajoz, Spain
| | - Rodrigo Pacheco
- Clinical Research Centre (CICAB), Centro de Investigación Clínica, Área de Salud de Badajoz, SES Servicio Extremeño de Salud, Hospital Universitario Infanta Cristina, 06080 Badajoz, Spain
| | - Idilio González
- LLerena Hospital Servicio Extremeño de Salud SES, LLerena, Spain
| | - Adrián LLerena
- Clinical Research Centre (CICAB), Centro de Investigación Clínica, Área de Salud de Badajoz, SES Servicio Extremeño de Salud, Hospital Universitario Infanta Cristina, 06080 Badajoz, Spain and Faculdade de Ciências da Saúde, Covilhã, Portugal
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Rodríguez-Antona C, Gurwitz D, de Leon J, Llerena A, Kirchheiner J, de Mesa EG, Ibarreta D. CYP2D6 genotyping for psychiatric patients treated with risperidone: considerations for cost–effectiveness studies. Pharmacogenomics 2009; 10:685-99. [DOI: 10.2217/pgs.09.15] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In order to ascertain data availability and feasibility for conducting cost–effectiveness studies in pharmacogenetics, and as part of a European Commission Joint Research Center, Institute for Prospective Technological Studies (JRC-IPTS) study, data concerning risperidone use and cytochrome P450 (CYP2D6) genotyping in medical care was collected in Germany, Spain and the USA, and are summarized in this perspective. The gene coding for CYP2D6 is highly polymorphic, resulting in a significant part of the population being poor metabolizers and ultrarapid metabolizers. Individuals who are CYP2D6 poor metabolizers, have an increased risk of adverse drug reactions (ADRs) when treated with CYP2D6-metabolized drugs, suggesting that CYP2D6 genotyping might be beneficial for patient care. This might be especially important in psychiatry, where approximately 50% of the patients use at least one drug primarily metabolized by CYP2D6. In particular, ADRs and poor response to treatment are major problems for some antipsychotics, including risperidone. However, there are no published cost–effectiveness studies on CYP2D6 genotyping, and the benefit that pharmacogenetic testing might represent by identifying problematic patients is still unclear. The present European Commission study found that current clinical and economical data concerning the frequency and direct healthcare costs of risperidone-related ADRs, the relation of such ADRs with the patients CYP2D6 genotypes, and costs for CYP2D6 genotyping, are not sufficient for determining if routine CYP2D6 genotyping might be cost beneficial for patients treated with risperidone. Therefore, efforts should be put on performing prospective cost–benefit studies with randomized treatment according to the CYP2D6 genotype to establish the utility of CYP2D6 genotyping for personalizing antipsychotic treatment.
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Affiliation(s)
| | | | | | - Adrián Llerena
- Extremadura University Hospital and Medical School, Badajoz, Spain
| | | | - Emma Gutiérrez de Mesa
- European Commission, Joint Research Center (JRC), Institute for Prospective Technological Studies (IPTS), Seville, Spain
| | - Dolores Ibarreta
- European Commission, Joint Research Center (JRC), Institute for Prospective Technological Studies (IPTS), Seville, Spain
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Miksys S, Tyndale RF. Brain drug-metabolizing cytochrome P450 enzymes are active in vivo, demonstrated by mechanism-based enzyme inhibition. Neuropsychopharmacology 2009; 34:634-40. [PMID: 18668033 PMCID: PMC5258186 DOI: 10.1038/npp.2008.110] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Individuals vary in their response to centrally acting drugs, and this is not always predicted by drug plasma levels. Central metabolism by brain cytochromes P450 (CYPs) may contribute to interindividual variation in response to drugs. Brain CYPs have unique regional and cell-type expression and induction patterns, and they are regulated independently of their hepatic isoforms. In vitro, these enzymes can metabolize endogenous and xenobiotic substrates including centrally acting drugs, but there is no evidence to date of their in vivo function. This has been difficult to demonstrate in the presence of hepatically derived metabolites that may cross the blood-brain barrier. In addition, because of the membrane location of brain CYPs and the rate limiting effect of endogenous heme levels on the activity and appropriate membrane insertion of some induced CYPs, it has been unclear whether sufficient cofactors and coenzymes are present for constitutive and induced CYP forms to be enzymatically active. We have developed a method using a radiolabeled mechanism-based inhibitor of CYP2B1, (3)H-8-methoxypsoralen, to demonstrate for the first time that both the constitutive and induced forms of this enzyme are active in situ in the living rat brain. This methodology provides a novel approach to assess the function of enzymes in extrahepatic tissues, where expression levels are often low. Selective induction of metabolically active drug metabolizing enzymes in the brain may also provide ways to control prodrug activation in specific brain regions as a novel therapeutic avenue.
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Affiliation(s)
- Sharon Miksys
- Centre for Addiction and Mental Health, Department of Pharmacology, University of Toronto, Toronto, ON, Canada.
| | - Rachel F Tyndale
- Centre for Addiction and Mental Health, University of Toronto, Toronto, ON, Canada,Department of Pharmacology, University of Toronto, Toronto, ON, Canada
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