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Silva S, Bicker J, Fialho S, Cunha S, Falcão A, Fortuna A. Intranasal delivery of paroxetine: A preclinical study on pharmacokinetics, depressive-like behaviour, and neurochemical sex differences. Biochem Pharmacol 2024; 223:116184. [PMID: 38556027 DOI: 10.1016/j.bcp.2024.116184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 03/09/2024] [Accepted: 03/29/2024] [Indexed: 04/02/2024]
Abstract
Treatment of major depressive disorder remains a major unmet clinical need. Given the advantages of intranasal administration for targeted brain delivery, the present study aimed at investigating the pharmacokinetics of paroxetine, after its intranasal instillation and assessing its potential therapeutic effect on female and male mice subjected to unpredictable chronic mild stress (UCMS) protocol. IN administration revealed direct nose-to-brain paroxetine delivery but dose- and sex-dependent differences. Pharmacokinetics was nonlinear and paroxetine concentrations were consistently higher in plasma and brain of male mice. Additionally, UCMS decreased animal preference for sucrose in both male and female mice following acute (p < 0.01) and chronic stress (p < 0.05), suggesting anhedonia. Both male and female mice exhibited depressive-like behavior in the forced swimming test. UCMS females displayed a significantly longer immobility time and shorter climbing time than the control group (p < 0.05), while no differences were found between male mice. Two weeks of paroxetine intranasal administration reduced immobility time and lengthened climbing and swimming time, approaching values similar to those observed in the healthy control group. The therapeutic effect was stronger on female mice. Importantly, melatonin plasma levels were significantly decreased in female mice following UCMS (p < 0.05), while males exhibited heightened corticosterone levels. On the other hand, treatment with IN paroxetine significantly increased corticosterone and melatonin levels in both sexes compared to healthy mice (p < 0.05). Intranasal paroxetine delivery undoubtedly ameliorated the behavioral despair, characteristic of depressive-like animals. Despite its efficiency in male and female mice subjected to UCMS, females were more prone to this novel therapeutic strategy.
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Affiliation(s)
- Soraia Silva
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal; CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Coimbra, Portugal
| | - Joana Bicker
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal; CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Coimbra, Portugal
| | - S Fialho
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Susana Cunha
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Amílcar Falcão
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal; CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Coimbra, Portugal
| | - Ana Fortuna
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal; CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Coimbra, Portugal.
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Kahma H, Aurinsalo L, Neuvonen M, Katajamäki J, Paludetto MN, Viinamäki J, Launiainen T, Filppula AM, Tornio A, Niemi M, Backman JT. An automated cocktail method for in vitro assessment of direct and time-dependent inhibition of nine major cytochrome P450 enzymes - application to establishing CYP2C8 inhibitor selectivity. Eur J Pharm Sci 2021; 162:105810. [PMID: 33753217 DOI: 10.1016/j.ejps.2021.105810] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/26/2021] [Accepted: 03/16/2021] [Indexed: 12/12/2022]
Abstract
We developed an in vitro high-throughput cocktail assay with nine major drug-metabolizing CYP enzymes, optimized for screening of time-dependent inhibition. The method was applied to determine the selectivity of the time-dependent CYP2C8 inhibitors gemfibrozil 1-O-β-glucuronide and clopidogrel acyl-β-D-glucuronide. In vitro incubations with CYP selective probe substrates and pooled human liver microsomes were conducted in 96-well plates with automated liquid handler techniques and metabolite concentrations were measured with quantitative UHPLC-MS/MS analysis. After determination of inter-substrate interactions and Km values for each reaction, probe substrates were divided into cocktails I (tacrine/CYP1A2, bupropion/CYP2B6, amodiaquine/CYP2C8, tolbutamide/CYP2C9 and midazolam/CYP3A4/5) and II (coumarin/CYP2A6, S-mephenytoin/CYP2C19, dextromethorphan/CYP2D6 and astemizole/CYP2J2). Time-dependent inhibitors (furafylline/CYP1A2, selegiline/CYP2A6, clopidogrel/CYP2B6, gemfibrozil 1-O-β-glucuronide/CYP2C8, tienilic acid/CYP2C9, ticlopidine/CYP2C19, paroxetine/CYP2D6 and ritonavir/CYP3A) and direct inhibitor (terfenadine/CYP2J2) showed similar inhibition with single substrate and cocktail methods. Established time-dependent inhibitors caused IC50 fold shifts ranging from 2.2 to 30 with the cocktail method. Under time-dependent inhibition conditions, gemfibrozil 1-O-β-glucuronide was a strong (>90% inhibition) and selective (<< 20% inhibition of other CYPs) inhibitor of CYP2C8 at concentrations ranging from 60 to 300 μM, while the selectivity of clopidogrel acyl-β-D-glucuronide was limited at concentrations above its IC80 for CYP2C8. The time-dependent IC50 values of these glucuronides for CYP2C8 were 8.1 and 38 µM, respectively. In conclusion, a reliable cocktail method including the nine most important drug-metabolizing CYP enzymes was developed, optimized and validated for detecting time-dependent inhibition. Moreover, gemfibrozil 1-O-β-glucuronide was established as a selective inhibitor of CYP2C8 for use as a diagnostic inhibitor in in vitro studies.
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Affiliation(s)
- Helinä Kahma
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland; Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Clinical Pharmacology, HUS Diagnostic Center, Helsinki University Hospital, Helsinki, Finland
| | - Laura Aurinsalo
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland; Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Mikko Neuvonen
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland; Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Jani Katajamäki
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland; Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Marie-Noëlle Paludetto
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland; Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Jenni Viinamäki
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland
| | - Terhi Launiainen
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland
| | - Anne M Filppula
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland; Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Aleksi Tornio
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland; Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Clinical Pharmacology, HUS Diagnostic Center, Helsinki University Hospital, Helsinki, Finland
| | - Mikko Niemi
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland; Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Clinical Pharmacology, HUS Diagnostic Center, Helsinki University Hospital, Helsinki, Finland
| | - Janne T Backman
- Department of Clinical Pharmacology, University of Helsinki, Helsinki, Finland; Individualized Drug Therapy Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Clinical Pharmacology, HUS Diagnostic Center, Helsinki University Hospital, Helsinki, Finland.
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Tolledo EC, Miksys S, Gonzalez FJ, Tyndale RF. Propranolol is a mechanism-based inhibitor of CYP2D and CYP2D6 in humanized CYP2D6-transgenic mice: Effects on activity and drug responses. Br J Pharmacol 2020; 177:701-712. [PMID: 31648367 DOI: 10.1111/bph.14884] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 08/16/2019] [Accepted: 09/13/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE Genetics and drug interactions contribute to large interindividual variation in human CYP2D6 activity. Here, we have characterized propranolol inhibition of human and mouse CYP2D using transgenic (TG) mice, which express both mouse CYP2D and human CYP2D6, and wild-type (WT) mice. Our purpose was to develop a method for in vivo manipulation of CYP2D6 enzyme activity which could be used to investigate the role of CYP2D6 in drug-induced behaviours. EXPERIMENTAL APPROACH Dextromethorphan metabolism to dextrorphan was used to measure CYP2D activity and to characterize propranolol inhibition in vitro and in vivo. Effects of propranolol pretreatment (24 hr) on serum levels of the CYP2D6 substrate haloperidol and haloperidol-induced catalepsy were also studied. KEY RESULTS Dextrorphan formation velocity in vitro was threefold higher in liver microsomes of TG compared to WT mice. Propranolol acted as a mechanism-based inhibitor (MBI), inactivating CYP2D in liver microsomes from TG and WT mice, and humans. Pretreatment (24 hr) of TG and WT mice with 20 mg·kg-1 intraperitoneal propranolol reduced dextrorphan formation in vivo and by liver microsomes in vitro. Serum haloperidol levels and catalepsy were increased. CONCLUSIONS AND IMPLICATIONS Propranolol was a potent MBI of dextrorphan formation in liver microsomes from TG and WT mice, and humans. The inhibition parameters in TG overlapped with those in WT mice and in humans. Inhibition of CYP2D with propranolol in vivo in TG and WT mice altered drug responses, allowing further investigation of variations in CYP2D6 on drug interactions and drug responses.
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Affiliation(s)
- Edgor Cole Tolledo
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Department of Pharmacology & Toxicology, Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Sharon Miksys
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Department of Pharmacology & Toxicology, Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Frank J Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Rachel F Tyndale
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Department of Pharmacology & Toxicology, Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
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Sánchez-Martín A, Sánchez-Iglesias S, García-Berrocal B, Lorenzo C, Gaedigk A, Isidoro-García M. Pharmacogenetics to prevent maniac affective switching with treatment for bipolar disorder: CYP2D6. Pharmacogenomics 2016; 17:1291-3. [PMID: 27469479 DOI: 10.2217/pgs-2016-0105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Almudena Sánchez-Martín
- Department of Pharmacy, University Hospital of Salamanca, Salamanca, Spain.,IBSAL, Salamanca Institute for Biomedical Research, Salamanca, Spain
| | - Santiago Sánchez-Iglesias
- IBSAL, Salamanca Institute for Biomedical Research, Salamanca, Spain.,Department of Psychiatry, University Hospital of Salamanca, Spain
| | - Belén García-Berrocal
- IBSAL, Salamanca Institute for Biomedical Research, Salamanca, Spain.,Department of Clinical Biochemistry, University Hospital of Salamanca, Spain
| | - Carolina Lorenzo
- IBSAL, Salamanca Institute for Biomedical Research, Salamanca, Spain.,Department of Psychiatry, University Hospital of Salamanca, Spain
| | - Andrea Gaedigk
- Division of Clinical Pharmacology, Toxicology & Therapeutic Innovation, Children's Mercy Hospital, Kansas City, MO, USA.,Department of Pediatrics, School of Medicine, University of Missouri-Kansas City, Kansas City, MO, USA
| | - María Isidoro-García
- IBSAL, Salamanca Institute for Biomedical Research, Salamanca, Spain.,Department of Clinical Biochemistry, University Hospital of Salamanca, Spain.,Department of Medicine, University of Salamanca, Spain
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Sánchez-Iglesias S, García-Solaesa V, García-Berrocal B, Sanchez-Martín A, Lorenzo-Romo C, Martín-Pinto T, Gaedigk A, González-Buitrago JM, Isidoro-García M. Role of Pharmacogenetics in Improving the Safety of Psychiatric Care by Predicting the Potential Risks of Mania in CYP2D6 Poor Metabolizers Diagnosed With Bipolar Disorder. Medicine (Baltimore) 2016; 95:e2473. [PMID: 26871771 PMCID: PMC4753865 DOI: 10.1097/md.0000000000002473] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
One of the main concerns in psychiatric care is safety related to drug management. Pharmacogenetics provides an important tool to assess causes that may have contributed the adverse events during psychiatric therapy. This study illustrates the potential of pharmacogenetics to identify those patients for which pharmacogenetic-guided therapy could be appropriate. It aimed to investigate CYP2D6 genotype in our psychiatric population to assess the value of introducing pharmacogenetics as a primary improvement for predicting side effects.A broad series of 224 psychiatric patients comprising psychotic disorders, depressive disturbances, bipolar disorders, and anxiety disorders was included. The patients were genotyped with the AmpliChip CYP450 Test to analyzing 33 allelic variants of the CYP2D6 gene.All bipolar patients with poor metabolizer status showed maniac switching when CYP2D6 substrates such as selective serotonin reuptake inhibitors were prescribed. No specific patterns were identified for adverse events for other disorders.We propose to utilize pharmacogenetic testing as an intervention to aid in the identification of patients who are at risk of developing affective switching in bipolar disorder treated with selective serotonin reuptake inhibitors, CYP2D6 substrates, and inhibitors.
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Affiliation(s)
- Santiago Sánchez-Iglesias
- From the Servicio de Psiquiatría, Hospital Universitario de Salamanca (SS-I, CL-R, TM-P); Instituto Biosanitario de Salamanca, IBSAL (VG-S, BG-B, AS-M, JML-R, MI-G); Servicio de Bioquímica Clínica, Hospital Universitario de Salamanca (BG-B, JMG-B, MI-G); Servicio de Farmacia, Hospital Universitario de Salamanca, Spain (AS-M); Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children's Mercy Hospital (AG); Department of Pediatrics, School of Medicine, University of Missouri-Kansas City, Kansas City, MO, USA (AG); and Departamento de Medicina, Universidad de Salamanca, Spain (MI-G)
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Medhasi S, Pasomsub E, Vanwong N, Ngamsamut N, Puangpetch A, Chamnanphon M, Hongkaew Y, Limsila P, Pinthong D, Sukasem C. Clinically relevant genetic variants of drug-metabolizing enzyme and transporter genes detected in Thai children and adolescents with autism spectrum disorder. Neuropsychiatr Dis Treat 2016; 12:843-51. [PMID: 27110117 PMCID: PMC4835132 DOI: 10.2147/ndt.s101580] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Single-nucleotide polymorphisms (SNPs) among drug-metabolizing enzymes and transporters (DMETs) influence the pharmacokinetic profile of drugs and exhibit intra- and interethnic variations in drug response in terms of efficacy and safety profile. The main objective of this study was to assess the frequency of allelic variants of drug absorption, distribution, metabolism, and elimination-related genes in Thai children and adolescents with autism spectrum disorder. Blood samples were drawn from 119 patients, and DNA was extracted. Genotyping was performed using the DMET Plus microarray platform. The allele frequencies of the DMET markers were generated using the DMET Console software. Thereafter, the genetic variations of significant DMET genes were assessed. The frequencies of SNPs across the genes coding for DMETs were determined. After filtering the SNPs, 489 of the 1,931 SNPs passed quality control. Many clinically relevant SNPs, including CYP2C19*2, CYP2D6*10, CYP3A5*3, and SLCO1B1*5, were found to have frequencies similar to those in the Chinese population. These data are important for further research to investigate the interpatient variability in pharmacokinetics and pharmacodynamics of drugs in clinical practice.
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Affiliation(s)
- Sadeep Medhasi
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand; Department of Pharmacology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Ekawat Pasomsub
- Division of Virology, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Natchaya Vanwong
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Nattawat Ngamsamut
- Yuwaprasart Waithayopathum Child and Adolescent Psychiatric Hospital, Department of Mental Health Services, Ministry of Public Health, Samut Prakarn, Thailand
| | - Apichaya Puangpetch
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Montri Chamnanphon
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Yaowaluck Hongkaew
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Penkhae Limsila
- Yuwaprasart Waithayopathum Child and Adolescent Psychiatric Hospital, Department of Mental Health Services, Ministry of Public Health, Samut Prakarn, Thailand
| | - Darawan Pinthong
- Department of Pharmacology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Chonlaphat Sukasem
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
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Caroleo B, Staltari O, Gallelli L, Perticone F. Reactivation of chronic hepatitis B during treatment with tenofovir disoproxil fumarate: drug interactions or low adherence? BMJ Case Rep 2015; 2015:bcr-2015-209586. [PMID: 26123461 DOI: 10.1136/bcr-2015-209586] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
We describe a case of a 61-year-old man with chronic hepatitis B, hepatitis B e antibody (HBeAb) positive, treated with tenofovir disoproxil fumarate (TDF), who developed virological and biochemical viremic reactivation with an increase in transaminase plasma levels. The patient's history revealed that he had discontinued TDF about 5 days before admission and, from December 2013, had been taking venlafaxine, paroxetine and zolpidem for some episodes of depression. Clinical evaluation and laboratory findings excluded the presence of systemic diseases that might have been able to explain the drug inefficacy, while pharmacological evaluation suggested a possible drug-drug interaction. In order to assess the possible occurrence of resistance, mutational analysis of hepatitis B virus (HBV) was performed and excluded the presence of resistance for TDF. TDF was prescribed, and venlafaxine, paroxetine and zolpidem were discontinued. The follow-up at 3, 6 and 12 months documented a good response to TDF with a time-related decrease of HBV-DNA and alanine aminotransferase.
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Shah RR, Smith RL. Addressing phenoconversion: the Achilles' heel of personalized medicine. Br J Clin Pharmacol 2015; 79:222-40. [PMID: 24913012 PMCID: PMC4309629 DOI: 10.1111/bcp.12441] [Citation(s) in RCA: 172] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 06/04/2014] [Indexed: 02/06/2023] Open
Abstract
Phenoconversion is a phenomenon that converts genotypic extensive metabolizers (EMs) into phenotypic poor metabolizers (PMs) of drugs, thereby modifying their clinical response to that of genotypic PMs. Phenoconversion, usually resulting from nongenetic extrinsic factors, has a significant impact on the analysis and interpretation of genotype-focused clinical outcome association studies and personalizing therapy in routine clinical practice. The high phenotypic variability or genotype-phenotype mismatch, frequently observed due to phenoconversion within the genotypic EM population, means that the real number of phenotypic PM subjects may be greater than predicted from their genotype alone, because many genotypic EMs would be phenotypically PMs. If the phenoconverted population with genotype-phenotype mismatch, most extensively studied for CYP2D6, is as large as the evidence suggests, there is a real risk that genotype-focused association studies, typically correlating only the genotype with clinical outcomes, may miss clinically strong pharmacogenetic associations, thus compromising any potential for advancing the prospects of personalized medicine. This review focuses primarily on co-medication-induced phenoconversion and discusses potential approaches to rectify some of the current shortcomings. It advocates routine phenotyping of subjects in genotype-focused association studies and proposes a new nomenclature to categorize study populations. Even with strong and reliable data associating patients' genotypes with clinical outcome(s), there are problems clinically in applying this knowledge into routine pharmacotherapy because of potential genotype-phenotype mismatch. Drug-induced phenoconversion during routine clinical practice remains a major public health issue. Therefore, the principal challenges facing personalized medicine, which need to be addressed, include identification of the following factors: (i) drugs that are susceptible to phenoconversion; (ii) co-medications that can cause phenoconversion; and (iii) dosage amendments that need to be applied during and following phenoconversion.
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Affiliation(s)
| | - Robert L Smith
- Department of Surgery and Cancer, Faculty of Medicine, Imperial CollegeLondon, UK
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Stevenson JM, Bishop JR. Genetic determinants of selective serotonin reuptake inhibitor related sexual dysfunction. Pharmacogenomics 2014; 15:1791-1806. [PMID: 25493571 DOI: 10.2217/pgs.14.114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Sexual dysfunction is a troubling obstacle for individuals being treated for depression and can be caused by both depressive symptoms as well as antidepressant drugs. Selective serotonin reuptake inhibitors (SSRIs) represent a class of antidepressants commonly associated with sexual dysfunction, even after symptomatic improvement. Candidate gene studies have identified associations between sexual dysfunction and altered SSRI pharmacokinetics or to the neurotransmitter systems affected by depression and SSRI treatment. The multifactorial nature of this phenotype and study heterogeneity are currently limitations to the translation of these findings to clinical use. Larger, prospective studies of genetic-guided antidepressant selection may help to clarify the clinical utility of pharmacogenetics in minimizing sexual side effects.
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Affiliation(s)
- James M Stevenson
- University of Illinois at Chicago College of Pharmacy, Department of Pharmacy Practice, Chicago, IL, USA
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