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Stern S, Hyland PL, Pacanowski M, Schuck RN. Leveraging in Vitro Models for Clinically Relevant Rare CYP2D6 Variants in Pharmacogenomics. Drug Metab Dispos 2024; 52:159-170. [PMID: 38167410 PMCID: PMC10877705 DOI: 10.1124/dmd.123.001512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/09/2023] [Accepted: 12/19/2023] [Indexed: 01/05/2024] Open
Abstract
Cytochrome P450 2D6 (CYP2D6) is responsible for the metabolism of up to 20% of small-molecule drugs and therefore, may impact the safety and efficacy of medicines in broad therapeutic areas. CYP2D6 is highly polymorphic, and the frequency of variants can differ across racial and ethnic populations, significantly affecting enzymatic function and drug metabolism. However, rare variants of CYP2D6 present a unique challenge for academia, industry, and regulatory agencies alike due to the lack of feasibility of characterizing their clinical relevance in clinical trials, particularly in variants that exhibit population-specific frequencies in racial and ethnic groups that are poorly represented in clinical trials. Despite significant advancement in pharmacogenomics, the substrate specificity and related clinical relevance of these CYP2D6 rare variants remain largely unclear, and further efforts are warranted to characterize the burden of these variants on adverse drug reactions and drug efficacy. Thus, cell-based in vitro systems can be used to inform substrate-specific effects and the overall relevance of a rare variant. Liver microsomes, cell-based expression systems, ex vivo primary samples, and purified variant protein have all been used with various substrates to potentially predict the clinical impact of new substrates. In this review, we identify rare variants of CYP2D6 that demonstrate differences across races in prevalence and thus are often unassessed in clinical trials. Accordingly, we examine current pharmacogenomic in vitro models used to analyze the functional impact of these rare variants in a substrate-specific manner. SIGNIFICANCE STATEMENT: Variants of CYP2D6 play a clinically relevant role in drug metabolism, leading to potential safety and efficacy concerns. Although the influence of prevalent variants is often well characterized, rare variants are traditionally not included in clinical trials. This review captures the clinical relevance of rare variants in CYP2D6 by highlighting in vitro models that analyze their impact on the metabolism of CYP2D6 substrates.
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Affiliation(s)
- Sydney Stern
- Center for Drug Evaluation and Research, Office of Translational Science, Office of Clinical Pharmacology, US Food and Drug Administration, Silver Spring, Maryland
| | - Paula L Hyland
- Center for Drug Evaluation and Research, Office of Translational Science, Office of Clinical Pharmacology, US Food and Drug Administration, Silver Spring, Maryland
| | - Michael Pacanowski
- Center for Drug Evaluation and Research, Office of Translational Science, Office of Clinical Pharmacology, US Food and Drug Administration, Silver Spring, Maryland
| | - Robert N Schuck
- Center for Drug Evaluation and Research, Office of Translational Science, Office of Clinical Pharmacology, US Food and Drug Administration, Silver Spring, Maryland
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Chamboko CR, Veldman W, Tata RB, Schoeberl B, Tastan Bishop Ö. Human Cytochrome P450 1, 2, 3 Families as Pharmacogenes with Emphases on Their Antimalarial and Antituberculosis Drugs and Prevalent African Alleles. Int J Mol Sci 2023; 24:ijms24043383. [PMID: 36834793 PMCID: PMC9961538 DOI: 10.3390/ijms24043383] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/30/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023] Open
Abstract
Precision medicine gives individuals tailored medical treatment, with the genotype determining the therapeutic strategy, the appropriate dosage, and the likelihood of benefit or toxicity. Cytochrome P450 (CYP) enzyme families 1, 2, and 3 play a pivotal role in eliminating most drugs. Factors that affect CYP function and expression have a major impact on treatment outcomes. Therefore, polymorphisms of these enzymes result in alleles with diverse enzymatic activity and drug metabolism phenotypes. Africa has the highest CYP genetic diversity and also the highest burden of malaria and tuberculosis, and this review presents current general information on CYP enzymes together with variation data concerning antimalarial and antituberculosis drugs, while focusing on the first three CYP families. Afrocentric alleles such as CYP2A6*17, CYP2A6*23, CYP2A6*25, CYP2A6*28, CYP2B6*6, CYP2B6*18, CYP2C8*2, CYP2C9*5, CYP2C9*8, CYP2C9*9, CYP2C19*9, CYP2C19*13, CYP2C19*15, CYP2D6*2, CYP2D6*17, CYP2D6*29, and CYP3A4*15 are implicated in diverse metabolic phenotypes of different antimalarials such as artesunate, mefloquine, quinine, primaquine, and chloroquine. Moreover, CYP3A4, CYP1A1, CYP2C8, CYP2C18, CYP2C19, CYP2J2, and CYP1B1 are implicated in the metabolism of some second-line antituberculosis drugs such as bedaquiline and linezolid. Drug-drug interactions, induction/inhibition, and enzyme polymorphisms that influence the metabolism of antituberculosis, antimalarial, and other drugs, are explored. Moreover, a mapping of Afrocentric missense mutations to CYP structures and a documentation of their known effects provided structural insights, as understanding the mechanism of action of these enzymes and how the different alleles influence enzyme function is invaluable to the advancement of precision medicine.
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Affiliation(s)
- Chiratidzo R Chamboko
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Makhanda 6139, South Africa
| | - Wayde Veldman
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Makhanda 6139, South Africa
| | - Rolland Bantar Tata
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Makhanda 6139, South Africa
| | - Birgit Schoeberl
- Translational Medicine, Novartis Institutes for BioMedical Research, 220 Massachusetts Ave, Cambridge, MA 02139, USA
| | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Makhanda 6139, South Africa
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Relevance of CYP2D6 Gene Variants in Population Genetic Differentiation. Pharmaceutics 2022; 14:pharmaceutics14112481. [PMID: 36432672 PMCID: PMC9694252 DOI: 10.3390/pharmaceutics14112481] [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: 10/13/2022] [Revised: 11/09/2022] [Accepted: 11/10/2022] [Indexed: 11/18/2022] Open
Abstract
A significant portion of the variability in complex features, such as drug response, is likely caused by human genetic diversity. One of the highly polymorphic pharmacogenes is CYP2D6, encoding an enzyme involved in the metabolism of about 25% of commonly prescribed drugs. In a directed search of the 1000 Genomes Phase III variation data, 86 single nucleotide polymorphisms (SNPs) in the CYP2D6 gene were extracted from the genotypes of 2504 individuals from 26 populations, and then used to reconstruct haplotypes. Analyses were performed using Haploview, Phase, and Arlequin softwares. Haplotype and nucleotide diversity were high in all populations, but highest in populations of African ancestry. Pairwise FST showed significant results for eleven SNPs, six of which were characteristic of African populations, while four SNPs were most common in East Asian populations. A principal component analysis of CYP2D6 haplotypes showed that African populations form one cluster, Asian populations form another cluster with East and South Asian populations separated, while European populations form the third cluster. Linkage disequilibrium showed that all African populations have three or more haplotype blocks within the CYP2D6 gene, while other world populations have one, except for Chinese Dai and Punjabi in Pakistan populations, which have two.
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Stojanović Marković A, Zajc Petranović M, Tomas Ž, Puljko B, Šetinc M, Škarić-Jurić T, Peričić Salihović M. Untangling SNP Variations within CYP2D6 Gene in Croatian Roma. J Pers Med 2022; 12:jpm12030374. [PMID: 35330374 PMCID: PMC8951754 DOI: 10.3390/jpm12030374] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/18/2022] [Accepted: 02/23/2022] [Indexed: 02/06/2023] Open
Abstract
CYP2D6 is a highly polymorphic gene whose variations affect its enzyme activity. To assess whether the specific population history of Roma, characterized by constant migrations and endogamy, influenced the distribution of alleles and thus phenotypes, the CYP2D6 gene was sequenced using NGS (Next Generation Sequencing) method-targeted sequencing in three groups of Croatian Roma (N = 323) and results were compared to European and Asian populations. Identified single nucleotide polymorphisms (SNPs) were used to reconstruct haplotypes, which were translated into the star-allele nomenclature and later into phenotypes. A total of 43 polymorphic SNPs were identified. The three Roma groups differed significantly in the frequency of alleles of polymorphisms 6769 A > G, 6089 G > A, and 5264 A > G (p < 0.01), as well as in the prevalence of the five most represented star alleles: *1, *2, *4, *10, and *41 (p < 0.0001). Croatian Roma differ from the European and Asian populations in the accumulation of globally rare SNPs (6089 G > A, 4589 C > T, 4622 G > C, 7490 T > C). Our results also show that demographic history influences SNP variations in the Roma population. The three socio-culturally different Roma groups studied differ significantly in the distribution of star alleles, which confirms the importance of a separate study of different Roma groups.
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Affiliation(s)
- Anita Stojanović Marković
- Institute for Anthropological Research, 10000 Zagreb, Croatia; (A.S.M.); (M.Z.P.); (M.Š.); (T.Š.-J.)
| | - Matea Zajc Petranović
- Institute for Anthropological Research, 10000 Zagreb, Croatia; (A.S.M.); (M.Z.P.); (M.Š.); (T.Š.-J.)
| | - Željka Tomas
- Department for Translational Medicine, Srebrnjak Children’s Hospital, 10000 Zagreb, Croatia;
| | - Borna Puljko
- Croatian Institute for Brain Research, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia;
- Department for Chemistry and Biochemistry, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Maja Šetinc
- Institute for Anthropological Research, 10000 Zagreb, Croatia; (A.S.M.); (M.Z.P.); (M.Š.); (T.Š.-J.)
| | - Tatjana Škarić-Jurić
- Institute for Anthropological Research, 10000 Zagreb, Croatia; (A.S.M.); (M.Z.P.); (M.Š.); (T.Š.-J.)
| | - Marijana Peričić Salihović
- Institute for Anthropological Research, 10000 Zagreb, Croatia; (A.S.M.); (M.Z.P.); (M.Š.); (T.Š.-J.)
- Correspondence:
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Review of Pharmacokinetics and Pharmacogenetics in Atypical Long-Acting Injectable Antipsychotics. Pharmaceutics 2021; 13:pharmaceutics13070935. [PMID: 34201784 PMCID: PMC8308912 DOI: 10.3390/pharmaceutics13070935] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/01/2021] [Accepted: 06/21/2021] [Indexed: 12/17/2022] Open
Abstract
Over the last two decades, pharmacogenetics and pharmacokinetics have been increasingly used in clinical practice in Psychiatry due to the high variability regarding response and side effects of antipsychotic drugs. Specifically, long-acting injectable (LAI) antipsychotics have different pharmacokinetic profile than oral formulations due to their sustained release characteristics. In addition, most of these drugs are metabolized by CYP2D6, whose interindividual genetic variability results in different metabolizer status and, consequently, into different plasma concentrations of the drugs. In this context, there is consistent evidence which supports the use of therapeutic drug monitoring (TDM) along with pharmacogenetic tests to improve safety and efficacy of antipsychotic pharmacotherapy. This comprehensive review aims to compile all the available pharmacokinetic and pharmacogenetic data regarding the three major LAI atypical antipsychotics: risperidone, paliperidone and aripiprazole. On the one hand, CYP2D6 metabolizer status influences the pharmacokinetics of LAI aripiprazole, but this relation remains a matter of debate for LAI risperidone and LAI paliperidone. On the other hand, developed population pharmacokinetic (popPK) models showed the influence of body weight or administration site on the pharmacokinetics of these LAI antipsychotics. The combination of pharmacogenetics and pharmacokinetics (including popPK models) leads to a personalized antipsychotic therapy. In this sense, the optimization of these treatments improves the benefit–risk balance and, consequently, patients’ quality of life.
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Botton MR, Whirl-Carrillo M, Del Tredici AL, Sangkuhl K, Cavallari LH, Agúndez JAG, Duconge J, Lee MTM, Woodahl EL, Claudio-Campos K, Daly AK, Klein TE, Pratt VM, Scott SA, Gaedigk A. PharmVar GeneFocus: CYP2C19. Clin Pharmacol Ther 2021; 109:352-366. [PMID: 32602114 PMCID: PMC7769975 DOI: 10.1002/cpt.1973] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 06/15/2020] [Indexed: 12/17/2022]
Abstract
The Pharmacogene Variation Consortium (PharmVar) catalogues star (*) allele nomenclature for the polymorphic human CYP2C19 gene. CYP2C19 genetic variation impacts the metabolism of many drugs and has been associated with both efficacy and safety issues for several commonly prescribed medications. This GeneFocus provides a comprehensive overview and summary of CYP2C19 and describes how haplotype information catalogued by PharmVar is utilized by the Pharmacogenomics Knowledgebase and the Clinical Pharmacogenetics Implementation Consortium (CPIC).
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Affiliation(s)
| | | | | | - Katrin Sangkuhl
- Department of Biomedical Data Science, Stanford University, Stanford, California, USA
| | | | - José A G Agúndez
- UNEx, ARADyAL, Instituto de Salud Carlos III, University Institute of Molecular Pathology Biomarkers, Cáceres, Spain
| | - Jorge Duconge
- School of Pharmacy, University of Puerto Rico, San Juan, Puerto Rico
| | | | - Erica L Woodahl
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, Montana, USA
| | | | - Ann K Daly
- Newcastle University, Newcastle upon Tyne, UK
| | - Teri E Klein
- Department of Biomedical Data Science, Stanford University, Stanford, California, USA
| | - Victoria M Pratt
- Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Stuart A Scott
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Sema4, Stamford, Connecticut, USA
| | - Andrea Gaedigk
- Division of Clinical Pharmacology, Toxicology & Therapeutic Innovation, Children's Mercy, Kansas City, Missouri, USA
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Zanger UM, Momoi K, Hofmann U, Schwab M, Klein K. Tri-Allelic Haplotypes Determine and Differentiate Functionally Normal Allele CYP2D6*2 and Impaired Allele CYP2D6*41. Clin Pharmacol Ther 2020; 109:1256-1264. [PMID: 33043448 DOI: 10.1002/cpt.2078] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 10/05/2020] [Indexed: 12/14/2022]
Abstract
CYP2D6 metabolizes 20-25% of all clinically used drugs and its complex genetic polymorphism is a major determinant of drug safety and efficacy. We investigated the basis for the functional difference between the two common alleles *2 (g.2851C>T + g.4181G>C, normal function) and *41 (additional intronic g.2989G>A, reduced function). A recently reported far-distant enhancer polymorphism rs5758550A/G linked to *2 has been suggested to play a decisive role. Genotyping of two white cohorts confirmed strong linkage of rs5758550G to *2, whereas no influence was found on metabolic ratio of sparteine or hepatic expression. Genomic plasmid constructs carrying individual variants or combinations thereof were expressed in COS1 and Huh7 cells. Both g.2851C>T(R296C) and g.2989G>A reduced enzyme activity and protein levels similarly by ~ 50-65% compared to reference (*1), whereas the double variant had only ~ 20% activity. Although the unexpected loss of function caused by g.2851C>T was compensated by g.4181G>C (mimicking the EM-phenotype of *2), the additional loss of function due to intronic g.2989G>A in the triple variant was not compensated (mimicking the IM-phenotype of *41). We also confirmed increased erroneous splicing in carriers of g.2989G>A but not of g.2851C>T as a likely explanation for the impaired function of *41. In conclusion, our data demonstrate g.2989G>A as causal variant of impaired allele CYP2D6*41 whereas triple-haplotypes have to be considered to explain the functional difference between *2 and *41. These data are important for genotyping strategies and clinical implementation of CYP2D6 pharmacogenetics.
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Affiliation(s)
- Ulrich M Zanger
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tuebingen, Tuebingen, Germany
| | - Kyoko Momoi
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tuebingen, Tuebingen, Germany
| | - Ute Hofmann
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tuebingen, Tuebingen, Germany
| | - Matthias Schwab
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tuebingen, Tuebingen, Germany
- Departments of Clinical Pharmacology, and of Pharmacy and Biochemistry, University Tuebingen, Tuebingen, Germany
| | - Kathrin Klein
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tuebingen, Tuebingen, Germany
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Spanakis M, Patelarou AE, Patelarou E. Nursing Personnel in the Era of Personalized Healthcare in Clinical Practice. J Pers Med 2020; 10:E56. [PMID: 32610469 PMCID: PMC7565499 DOI: 10.3390/jpm10030056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 06/24/2020] [Accepted: 06/26/2020] [Indexed: 12/27/2022] Open
Abstract
Personalized, stratified, or precision medicine (PM) introduces a new era in healthcare that tries to identify and predict optimum treatment outcomes for a patient or a cohort. It also introduces new scientific terminologies regarding therapeutic approaches and the need of their adoption from healthcare providers. Till today, evidence-based practice (EBP) was focusing on population averages and their variances among cohorts for clinical values that are essential for optimizing healthcare outcome. It can be stated that EBP and PM are complementary approaches for a modern healthcare system. Healthcare providers through EBP often see the forest (population averages) but miss the trees (individual patients), whereas utilization of PM may not see the forest for the trees. Nursing personnel (NP) play an important role in modern healthcare since they are consulting, educating, and providing care to patients whose needs often needs to be individualized (personalized nursing care, PNC). Based on the clinical issues earlier addressed from clinical pharmacology, EBP, and now encompassed in PM, this review tries to describe the challenges that NP have to face in order to meet the requisites of the new era in healthcare. It presents the demands that should be met for upgrading the provided education and expertise of NP toward an updated role in a modern healthcare system.
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Affiliation(s)
- Marios Spanakis
- Computational BioMedicine Laboratory, Institute of Computer Science, Foundation for Research and Technology—Hellas (FORTH), Heraklion, GR-70013 Crete, Greece
- Department of Nursing, Faculty of Health Sciences, Hellenic Mediterranean University, Heraklion, GR-71004 Crete, Greece; (A.E.P.); (E.P.)
| | - Athina E. Patelarou
- Department of Nursing, Faculty of Health Sciences, Hellenic Mediterranean University, Heraklion, GR-71004 Crete, Greece; (A.E.P.); (E.P.)
| | - Evridiki Patelarou
- Department of Nursing, Faculty of Health Sciences, Hellenic Mediterranean University, Heraklion, GR-71004 Crete, Greece; (A.E.P.); (E.P.)
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Khalyfa A, Sanz-Rubio D. Genetics and Extracellular Vesicles of Pediatrics Sleep Disordered Breathing and Epilepsy. Int J Mol Sci 2019; 20:ijms20215483. [PMID: 31689970 PMCID: PMC6862182 DOI: 10.3390/ijms20215483] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/14/2019] [Accepted: 10/28/2019] [Indexed: 12/27/2022] Open
Abstract
Sleep remains one of the least understood phenomena in biology, and sleep disturbances are one of the most common behavioral problems in childhood. The etiology of sleep disorders is complex and involves both genetic and environmental factors. Epilepsy is the most popular childhood neurological condition and is characterized by an enduring predisposition to generate epileptic seizures, and the neurobiological, cognitive, psychological, and social consequences of this condition. Sleep and epilepsy are interrelated, and the importance of sleep in epilepsy is less known. The state of sleep also influences whether a seizure will occur at a given time, and this differs considerably for various epilepsy syndromes. The development of epilepsy has been associated with single or multiple gene variants. The genetics of epilepsy is complex and disorders exhibit significant genetic heterogeneity and variability in the expressivity of seizures. Phenobarbital (PhB) is the most widely used antiepileptic drug. With its principal mechanism of action to prolong the opening time of the γ-aminobutyric acid (GABA)-A receptor-associated chloride channel, it enhances chloride anion influx into neurons, with subsequent hyperpolarization, thereby reducing excitability. Enzymes that metabolize pharmaceuticals including PhB are well known for having genetic polymorphisms that contribute to adverse drug–drug interactions. PhB metabolism is highly dependent upon the cytochrome P450 (CYP450) and genetic polymorphisms can lead to variability in active drug levels. The highly polymorphic CYP2C19 isozymes are responsible for metabolizing a large portion of routinely prescribed drugs and variants contribute significantly to adverse drug reactions and therapeutic failures. A limited number of CYP2C19 single nucleotide polymorphisms (SNPs) are involved in drug metabolism. Extracellular vesicles (EVs) are circular membrane fragments released from the endosomal compartment as exosomes are shed from the surfaces of the membranes of most cell types. Increasing evidence indicated that EVs play a pivotal role in cell-to-cell communication. Theses EVs may play an important role between sleep, epilepsy, and treatments. The discovery of exosomes provides potential strategies for the diagnosis and treatment of many diseases including neurocognitive deficit. The aim of this study is to better understand and provide further knowledge about the metabolism and interactions between phenobarbital and CYP2C19 polymorphisms in children with epilepsy, interplay between sleep, and EVs. Understanding this interplay between epilepsy and sleep is helpful in the optimal treatment of all patients with epileptic seizures. The use of genetics and extracellular vesicles as precision medicine for the diagnosis and treatment of children with sleep disorder will improve the prognosis and the quality of life in patients with epilepsy.
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Affiliation(s)
- Abdelnaby Khalyfa
- Department of Pediatrics, Section of Sleep Medicine, The University of Chicago, Chicago, IL 60637, USA.
- Department of Child Health and the Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA.
| | - David Sanz-Rubio
- Department of Child Health and the Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA.
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Salyakina D, Roy S, Wang W, Oliva M, Akhouri R, Sotto I, Mulas N, Solano R, Fernández JR, Sanchez S, Shamshad U, Perlyn C, McCafferty-Fernandez J. Results and challenges of Cytochrome P450 2D6 (CYP2D6) testing in an ethnically diverse South Florida population. Mol Genet Genomic Med 2019; 7:e922. [PMID: 31389673 PMCID: PMC6732280 DOI: 10.1002/mgg3.922] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 07/16/2019] [Accepted: 07/17/2019] [Indexed: 12/20/2022] Open
Abstract
Background This study focuses on the implementation of CYP2D6 genetic test profiling and the challenges associated with using standard pharmacogenetics panels in a diverse South Florida population. Methods A total of 413 participants were recruited to participate in this study through Nicklaus Children's Hospital. Buccal swabs were collected and tested using an extended CYP2D6 panel including 22 alleles. Phenotype, genotype, and allelic frequencies were compared among different racial and ethnic groups. Results The majority of participants (75.0%) self‐identified as Hispanics. Four alleles, CYP2D6*4, *17, *41, and *2A, showed a statistically significant difference between White Hispanics and Black Non‐Hispanics. Aggregate frequency of all alleles with decreased function varied between 2.8% and 50.0% in different racial and ethnic groups. Additionally, rare allele combinations were observed in this South Florida cohort. Conclusions The heterogeneity among Hispanic groups demonstrated in previous literature and by this study reflects the complexity of ethnicity and suggests that a more granular categorization is needed, one based on ancestry and migration history rather than primary language. Overall, we have determined that there are statistically significant differences in CYP2D6 allele frequencies in the distinct racial and ethnic populations of South Florida, demonstrating a unique genetic makeup within South Florida. However, overall, the frequencies of Poor Metabolizer, Normal Metabolizer, Intermediate Metabolizer, and Ultrarapid Metabolizer did not differ between racial and ethnic groups at a statistically significant level.
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Affiliation(s)
- Daria Salyakina
- Research Institute, Nicklaus Children's Hospital, Miami, Florida
| | - Sharmeen Roy
- Research Institute, Nicklaus Children's Hospital, Miami, Florida
| | - Weize Wang
- Research Institute, Nicklaus Children's Hospital, Miami, Florida
| | - Mailin Oliva
- Research Institute, Nicklaus Children's Hospital, Miami, Florida
| | - Rohan Akhouri
- Research Institute, Nicklaus Children's Hospital, Miami, Florida
| | - Ileana Sotto
- Research Institute, Nicklaus Children's Hospital, Miami, Florida
| | - Nicole Mulas
- Research Institute, Nicklaus Children's Hospital, Miami, Florida
| | - Rafaela Solano
- Research Institute, Nicklaus Children's Hospital, Miami, Florida
| | - José R Fernández
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama
| | | | - Uzma Shamshad
- Research Institute, Nicklaus Children's Hospital, Miami, Florida
| | - Chad Perlyn
- Research Institute, Nicklaus Children's Hospital, Miami, Florida.,Herbert Wertheim College of Medicine, Florida International University, Miami, Florida
| | - Jennifer McCafferty-Fernandez
- Research Institute, Nicklaus Children's Hospital, Miami, Florida.,Herbert Wertheim College of Medicine, Florida International University, Miami, Florida
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A Single Site Population Study to Investigate CYP2D6 Phenotype of Patients with Persistent Non-Malignant Pain. ACTA ACUST UNITED AC 2019; 55:medicina55060220. [PMID: 31141989 PMCID: PMC6631257 DOI: 10.3390/medicina55060220] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 05/17/2019] [Accepted: 05/23/2019] [Indexed: 01/08/2023]
Abstract
Background and Objectives: Codeine requires biotransformation by the CYP2D6 enzyme, encoded by the polymorphic CYP2D6 gene, to morphine for therapeutic efficacy. CYP2D6 phenotypes of poor, intermediate, and ultra-rapid metabolisers are at risk of codeine non-response and adverse drug reactions due to altered CYP2D6 function. The aim of this study was to determine whether genotype, inferred phenotype, and urinary and oral fluid codeine O-demethylation metabolites could predict codeine non-response following a short course of codeine. Materials and Methods: There were 131 Caucasians with persistent pain enrolled. Baseline assessments were recorded, prohibited medications ceased, and DNA sampling completed before commencing codeine 30 mg QDS for 5 days. Day 4 urine samples were collected 1–2 h post morning dose for codeine O-demethylation metabolites analysis. Final pain assessments were conducted on day 5. Results: None of the poor, intermediate, ultra-rapid metabolisers and only 24.5% of normal metabolisers responded to codeine. A simple scoring system to predict analgesic response from day 4 urinary metabolites was devised with overall prediction success of 79% (sensitivity 0.8, specificity 0.78) for morphine and 79% (sensitivity 0.76, specificity 0.83) for morphine:creatinine ratio. Conclusions: In conclusion, this study provides tentative evidence that day 4 urinary codeine O-demethylation metabolites could predict non-response following a short course of codeine and could be utilised in the clinical assessment of codeine response at the point of care to improve analgesic efficacy and safety in codeine therapy. We offer a scoring system to predict codeine response from urinary morphine and urinary morphine:creatinine ratio collected on the morning of day 4 of codeine 30 mg QDS, but this requires validation before it could be considered for use to assess codeine response in clinical practice.
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Jarvis JP, Peter AP, Shaman JA. Consequences of CYP2D6 Copy-Number Variation for Pharmacogenomics in Psychiatry. Front Psychiatry 2019; 10:432. [PMID: 31281270 PMCID: PMC6595891 DOI: 10.3389/fpsyt.2019.00432] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 06/03/2019] [Indexed: 12/20/2022] Open
Abstract
Pharmacogenomics represents a potentially powerful enhancement to the current standard of care for psychiatric patients. However, a variety of biological and technical challenges must be addressed in order to provide adequate clinical decision support for personalized prescribing and dosing based on genomic data. This is particularly true in the case of CYP2D6, a key drug-metabolizing gene, which not only harbors multiple genetic variants known to affect enzyme function but also shows a broad range of copy-number and hybrid alleles in various patient populations. Here, we describe several challenges in the accurate measurement and interpretation of data from the CYP2D6 locus including the clinical consequences of increased copy number. We discuss best practices for overcoming these challenges and then explore various current and future applications of pharmacogenomic analysis of CYP2D6 in psychiatry.
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13
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Rahikainen AL, Vauhkonen P, Pett H, Palo JU, Haukka J, Ojanperä I, Niemi M, Sajantila A. Completed suicides of citalopram users-the role of CYP genotypes and adverse drug interactions. Int J Legal Med 2018; 133:353-363. [PMID: 30173302 DOI: 10.1007/s00414-018-1927-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 08/24/2018] [Indexed: 12/25/2022]
Abstract
Depression is known to be a risk factor for suicide. Currently, the most used antidepressants are selective serotonin reuptake inhibitors (SSRIs). Not all users, however, benefit from them. In such cases, treatment failure can be explained in part by genetic differences. In this study, we investigated the role of pharmacogenetic factors in citalopram-positive completed suicides (n = 349). Since citalopram is metabolized by CYP2C19 and CYP2D6 enzymes, the study population was genotyped for clinically relevant CYP2C19 and CYP2D6 polymorphisms and CYP2D6 copy number variation. To assess genetic differences between suicide cases and Finns in general, Finnish population samples (n = 855) were used as controls. Also, the role of drug interactions among suicide cases was evaluated. We found enrichment of a combined group of genetically predicted poor and ultrarapid metabolizer phenotypes (gMPs) of CYP2C19 among suicide victims compared to controls 0.356 [0.31-0.41] vs. 0.265 [0.24-0.30] (p = 0.0065). In CYP2D6 gMPs, there was no difference between cases and controls when the study population was analyzed as a whole. However, there were significantly more poor metabolizers among females who committed suicide by poisoning compared to female controls. In 8% of all drug poisoning deaths, lifetime drug-drug interaction was evaluated having a contribution to the fatal outcome. From clinical perspective, pharmacogenetic testing prior to initiation of SSRI drug could be beneficial. It may also be useful in medico-legal settings as it may elucidate obscure poisoning cases. Also, the possibility of unintentional drug interactions should be taken into account in drug poisoning deaths.
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Affiliation(s)
- Anna-Liina Rahikainen
- Department of Forensic Medicine, University of Helsinki, P.O.Box 40, Kytösuontie 11, 00014, Helsinki, Finland.
| | - P Vauhkonen
- Forensic Medicine Unit, National Institute for Health and Welfare, P.O.Box 30, Mannerheimintie 166, 00271, Helsinki, Finland
| | - H Pett
- Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, the Netherlands.,Department of Clinical Pharmacology, University of Helsinki and Helsinki University Central Hospital, P.O.Box 20, Tukholmankatu 8C, 00014, Helsinki, Finland
| | - J U Palo
- Department of Forensic Medicine, University of Helsinki, P.O.Box 40, Kytösuontie 11, 00014, Helsinki, Finland.,Forensic Genetics Unit, National Institute for Health and Welfare, P.O.Box 30, Mannerheimintie 166, 00271, Helsinki, Finland
| | - J Haukka
- Department of Public Health, University of Helsinki, P.O.Box 20, Tukholmankatu 8B, 00014, Helsinki, Finland
| | - I Ojanperä
- Department of Forensic Medicine, University of Helsinki, P.O.Box 40, Kytösuontie 11, 00014, Helsinki, Finland.,Forensic Toxicology Unit, National Institute for Health and Welfare, P.O.Box 30, Mannerheimintie 166, 00271, Helsinki, Finland
| | - M Niemi
- Department of Clinical Pharmacology, University of Helsinki and Helsinki University Central Hospital, P.O.Box 20, Tukholmankatu 8C, 00014, Helsinki, Finland
| | - Antti Sajantila
- Department of Forensic Medicine, University of Helsinki, P.O.Box 40, Kytösuontie 11, 00014, Helsinki, Finland.
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14
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Gaedigk A, Ingelman‐Sundberg M, Miller NA, Leeder JS, Whirl‐Carrillo M, Klein TE. The Pharmacogene Variation (PharmVar) Consortium: Incorporation of the Human Cytochrome P450 (CYP) Allele Nomenclature Database. Clin Pharmacol Ther 2018; 103:399-401. [PMID: 29134625 PMCID: PMC5836850 DOI: 10.1002/cpt.910] [Citation(s) in RCA: 279] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/02/2017] [Accepted: 10/11/2017] [Indexed: 01/08/2023]
Abstract
The Human Cytochrome P450 (CYP) Allele Nomenclature Database, a critical resource for the pharmacogenetics and genomics communities, has transitioned to the Pharmacogene Variation (PharmVar) Consortium. In this report we provide a summary of the current database, provide an overview of the PharmVar consortium, and highlight the PharmVar database which will serve as the new home for pharmacogene nomenclature.
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Affiliation(s)
- Andrea Gaedigk
- Division of Clinical Pharmacology, Toxicology & Therapeutic Innovation, Children's Mercy Kansas City, and School of MedicineUniversity of Missouri‐Kansas CityKansas CityMissouriUSA
| | - Magnus Ingelman‐Sundberg
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska InstitutetStockholmSweden
| | - Neil A. Miller
- Center for Pediatric Genomic Medicine, Children's Mercy Kansas CityKansas CityMissouriUSA
| | - J. Steven Leeder
- Division of Clinical Pharmacology, Toxicology & Therapeutic Innovation, Children's Mercy Kansas City, and School of MedicineUniversity of Missouri‐Kansas CityKansas CityMissouriUSA
| | | | - Teri E. Klein
- Department of GeneticsStanford UniversityStanfordCaliforniaUSA
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15
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16
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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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17
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Lee YH, Bae SC. Association between Functional CYP2D6 Polymorphisms and Susceptibility to Autoimmune Diseases: A Meta-Analysis. Immunol Invest 2016; 46:109-122. [PMID: 27749127 DOI: 10.1080/08820139.2016.1226898] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE This study aimed to explore whether functional CYP2D6 polymorphisms are associated with susceptibility to autoimmune diseases. METHODS A meta-analysis was conducted on associations between autoimmune diseases and functional CYP2D6*4 1934 A/G and *3 polymorphisms and CYP2D6 phenotypes. RESULTS Twelve studies with 1,472 patients and 3,328 controls were included. Autoimmune disease and the CYP2D6 1934 A allele were significantly associated in the overall group, consistent with the Hardy-Weinberg equilibrium (OR = 1.227, 95% CI = 1.071-1.406, p = 0.003); stratification by ethnicity indicated that the CYP2D6 1934 A allele and autoimmune diseases were associated in Caucasians (OR = 1.225, 95% CI = 1.010-1.485, p = 0.039). The CYP2D6*3 allele was also associated with autoimmune diseases in Caucasians (OR = 1.977, 95% CI = 1.125-3.472, p = 0.018). Stratified by autoimmune disease type revealed that the CYP2D6 1934 AA genotype was associated with systemic lupus erythematosus (SLE; OR = 2.007, 95% CI = 1.170-3.442, p = 0.011) and ankylosing spondylitis (AS; OR = 2.317, 95% CI = 1.422-3.774, p = 0.001). The CYP2D6 PM+IM phenotype was significantly associated with autoimmune diseases in Caucasians (OR = 1.526, 95% CI = 1.038-2.246, p = 0.032) and with SLE (OR = 1.778, 95% CI = 1.249-2.532, p = 0.001). CONCLUSIONS This meta-analysis indicates that CYP2D6*4 and *3 polymorphisms and the CYP2D6 phenotype are associated with susceptibility to autoimmune diseases in Caucasians; particularly, the CYP2D6*4 polymorphism and CYP2D6 PM+IM phenotype are risk factors for SLE development.
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Affiliation(s)
- Young Ho Lee
- a Division of Rheumatology, Department of Internal Medicine , Korea University College of Medicine , Seoul , Korea
| | - Sang-Cheol Bae
- b Department of Rheumatology , Hanyang University Hospital for Rheumatic Diseases , Seoul , Korea
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18
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Šimić I, Potočnjak I, Kraljičković I, Stanić Benić M, Čegec I, Juričić Nahal D, Ganoci L, Božina N. CYP2D6 *6/*6 genotype and drug interactions as cause of haloperidol-induced extrapyramidal symptoms. Pharmacogenomics 2016; 17:1385-9. [PMID: 27469576 DOI: 10.2217/pgs-2016-0069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
A 66-year-old male Caucasian, received 1 mg of haloperidol orally and rapidly developed severe iatrogenic extrapyramidal symptoms. Treatment was immediately discontinued, and the side effects resolved. Haloperidol is mainly metabolized by Phase I CYP2D6 and to the lesser extent by CYP3A4 and by Phase II UGT2B7 enzymes. Genotyping was performed revealing CYP2D6*6/*6, CYP3A4*1/*1, and UGT2B7 -161 C/T genotypes, implicating poor, extensive and intermediate metabolism, respectively. Of the CYPs, haloperidol is metabolized by CYP2D6 and CYP3A4 primarily. It was the introduction of ciprofloxacin which was a trigger for the development of adverse drug reaction due to inhibition of CYP3A4, which was in presented patient main metabolic pathway for haloperidol since he was CYP2D6 poor metabolizer. Presented case report highlights the importance of genotyping. Pharmacogenetics testing should be considered when drug toxicity is suspected, polymorphic metabolic pathways used and drugs concomitantly applied.
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Affiliation(s)
- Iveta Šimić
- University of Zagreb School of Medicine, Zagreb, Croatia.,Division of Clinical Pharmacology, Department of Internal Medicine, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Ines Potočnjak
- Clinical Unit of Clinical Pharmacology & Toxicology, Department of Medicine, University Hospital Centre Sisters of Charity, Zagreb, Croatia
| | - Iva Kraljičković
- Division of Clinical Pharmacology, Department of Internal Medicine, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Mirjana Stanić Benić
- Unit for Clinical Pharmacology, University Hospital Centre Rijeka, Rijeka, Croatia
| | - Ivana Čegec
- Division of Clinical Pharmacology, Department of Internal Medicine, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Danica Juričić Nahal
- Division of Clinical Pharmacology, Department of Internal Medicine, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Lana Ganoci
- University of Zagreb School of Medicine, Zagreb, Croatia.,Department of Laboratory Diagnostics, University Hospital Centre Zagreb, University of Zagreb School of Medicine, Zagreb, Croatia
| | - Nada Božina
- University of Zagreb School of Medicine, Zagreb, Croatia.,Department of Laboratory Diagnostics, University Hospital Centre Zagreb, University of Zagreb School of Medicine, Zagreb, Croatia
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19
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Tverdohleb T, Dinc B, Knezevic I, Candido KD, Knezevic NN. The role of cytochrome P450 pharmacogenomics in chronic non-cancer pain patients. Expert Opin Drug Metab Toxicol 2016; 12:1303-1311. [PMID: 27388970 DOI: 10.1080/17425255.2016.1209482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Pharmacogenomics is the field that studies an individualized treatment approach for patients' medication regimen that can impact drug safety, productivity, and personalized health care. Pharmacogenomics characterizes the genetic differences in metabolic pathways which can affect a patient's individual responses to drug treatments. Areas covered: The various responses to pharmacological agents are mainly determined by the different types of genetic variants of the CYP450. CYP2D6 polymorphism is well known for its variation in the metabolism of drugs from many therapeutic arenas, including some analgesic drugs such as codeine, hydromorphone, oxycodone and tramadol. Allele combinations determine the phenotypic expression, characterized as either: extensive metabolizer, intermediate metabolizer, ultra-rapid metabolizer and poor metabolizer. Expert opinion: The Human Genome Project (HGP) revolutionized the future of medicine and the way health care providers approach individualized patient treatment, and chronic pain management is one of those areas. The key findings in the literature appear to be related to the CYP2D6 expression and its high polymorphism influencing the metabolism of opioid medications, and the impact of that on the patient's therapeutic outcome thus exemplifying the importance of genetic testing for CYP2D6 in the process of physician therapeutic decision making.
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Affiliation(s)
- Tatiana Tverdohleb
- a Department of Anesthesiology , Advocate Illinois Masonic Medical Center , Chicago , IL , USA
| | - Bora Dinc
- a Department of Anesthesiology , Advocate Illinois Masonic Medical Center , Chicago , IL , USA
| | - Ivana Knezevic
- a Department of Anesthesiology , Advocate Illinois Masonic Medical Center , Chicago , IL , USA
| | - Kenneth D Candido
- a Department of Anesthesiology , Advocate Illinois Masonic Medical Center , Chicago , IL , USA.,b Department of Anesthesiology, College of Medicine , University of Illinois , Chicago , IL , USA.,c Department of Surgery, College of Medicine , University of Illinois , Chicago , IL , USA
| | - Nebojsa Nick Knezevic
- a Department of Anesthesiology , Advocate Illinois Masonic Medical Center , Chicago , IL , USA.,b Department of Anesthesiology, College of Medicine , University of Illinois , Chicago , IL , USA.,c Department of Surgery, College of Medicine , University of Illinois , Chicago , IL , USA
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20
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Hu XX, Yuan LJ, Fang P, Mao YH, Zhan YY, Li XY, Dai DP, Cai JP, Hu GX. Effect of CYP2D6 genetic polymorphism on the metabolism of citalopram in vitro. Drug Metab Pharmacokinet 2016; 31:133-8. [PMID: 27016952 DOI: 10.1016/j.dmpk.2016.01.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 12/21/2015] [Accepted: 01/14/2016] [Indexed: 12/17/2022]
Abstract
Genetic polymorphisms of CYP2D6 significantly influence the efficacy and safety of some drugs, which might cause adverse effects and therapeutic failure. We aimed at investigating the role of CYP2D6 in the metabolism of citalopram and identifying the effect of 24 CYP2D6 allelic variants we found in Chinese Han population on the metabolism of citalopram in vitro. These CYP2D6 variants expressed by insect cells system were incubated with 10-1000 μM citalopram for 30 min at 37 °C and the reaction was terminated by cooling to -80 °C immediately. Citalopram and its metabolites were analyzed by high-performance liquid chromatography (HPLC). The intrinsic clearance (Vmax/Km) values of the variants toward citalopram metabolites were significantly altered, 38-129% for demethylcitalopram and 13-138% for citalopram N-oxide when compared with CYP2D6*1. Most of the tested rare alleles exhibited significantly decreased values due to increased Km and/or decreased Vmax values. We conclude that recombinant system could be used to investigate the enzymes involved in drug metabolism and these findings suggest that more attention should be paid to subjects carrying these CYP2D6 alleles when administering citalopram in the clinic.
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Affiliation(s)
- Xiao-Xia Hu
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ling-Jing Yuan
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ping Fang
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yong-Hui Mao
- Department of Nephrology, Beijing Hospital, Ministry of Health, Beijing, China
| | - Yun-Yun Zhan
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiang-Yu Li
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Da-Peng Dai
- The Key Laboratory of Geriatrics, Beijing Hospital, Beijing Institute of Geriatrics, Ministry of Health, Beijing, China
| | - Jian-Ping Cai
- The Key Laboratory of Geriatrics, Beijing Hospital, Beijing Institute of Geriatrics, Ministry of Health, Beijing, China.
| | - Guo-Xin Hu
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China.
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21
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Ward MB, Sorich MJ, McKinnon RA. Cytochrome P450 Part 2: Genetics of Inter-Individual Variability. JOURNAL OF PHARMACY PRACTICE AND RESEARCH 2015. [DOI: 10.1002/j.2055-2335.2008.tb00845.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
| | | | - Ross A McKinnon
- Sansom Institute, School of Pharmacy and Medical Sciences; University of South Australia; Adelaide South Australia
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22
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A Compartmental Analysis for Morphine and Its Metabolites in Young Children After a Single Oral Dose. Clin Pharmacokinet 2015; 54:1083-90. [DOI: 10.1007/s40262-015-0256-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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23
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Mahmood I. Prediction of drug clearance in children: a review of different methodologies. Expert Opin Drug Metab Toxicol 2015; 11:573-87. [DOI: 10.1517/17425255.2015.1019463] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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24
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Confronting the challenges of effective pain management in children following tonsillectomy. Int J Pediatr Otorhinolaryngol 2014; 78:1813-27. [PMID: 25241379 DOI: 10.1016/j.ijporl.2014.08.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 08/11/2014] [Indexed: 12/29/2022]
Abstract
Tonsillectomy is an extremely common surgical procedure associated with significant morbidity and mortality. The post-operative challenges include: respiratory complications, post-tonsillectomy hemorrhage, nausea, vomiting and significant pain. The present model of care demands that most of these children are managed in an ambulatory setting. The recent Federal Drug Agency (FDA) warning contraindicating the use of codeine after tonsillectomy in children represents a significant change of practice for many pediatric otolaryngological surgeons. This introduces a number of other safety concerns when deciding on a safe alternative to codeine, especially since most tonsillectomy patients are managed by lay primary caregiver's at home. This review outlines the safety issues and proposes, based on currently available evidence, a preventative multi-modal strategy to manage pain, nausea and vomiting without increasing the risk of post-tonsillectomy bleeding.
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25
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Ballas SK. Pathophysiology and principles of management of the many faces of the acute vaso-occlusive crisis in patients with sickle cell disease. Eur J Haematol 2014; 95:113-23. [PMID: 25288149 DOI: 10.1111/ejh.12460] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/02/2014] [Indexed: 12/11/2022]
Abstract
Effective management of sickle cell pain entails a thorough understanding of its pathophysiology and the pharmacogenomics of the opioids used to manage it. In recent years, there has been significant progress along these two lines. At the pathophysiologic level, there is evidence that the severity and frequency of painful stimuli modulate their transmission at the level of the dorsal horn of the spinal cord. This modulation is achieved via two channels: the α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and NMDA receptors. Initially, the AMPA channel controls the transmission of stimuli of mild-moderate severity. Once the AMPA channel reaches its limit of membrane depolarization, the NMDA channel is activated and facilitates the transmission of painful stimuli in a progressive fashion leading to central sensitization and glial activation. At the level of pharmacogenomics, the metabolism of each opioid is patient-specific. Glucuronidation is unique for the metabolism of morphine, hydromorphone, and oxymorphone. The metabolism of all other opioids requires specific Cytochrome P450 (CYP) isoenzymes. The activity of each isoenzyme and the activity of the metabolites of each opioid vary among patients depending on their genetic makeup and coexistent environmental factors such as the use of other medications that may enhance or inhibit the CYP isoenzyme activity.
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Affiliation(s)
- Samir K Ballas
- Cardeza Foundation for Hematologic Research, Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA, USA
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26
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Abstract
OBJECTIVE As genotyping technology has progressed, genome-wide association studies (GWAS) have matured into efficient and effective tools for mapping genes underlying human phenotypes. METHODS Recent studies have shown the utility of the GWAS approach for examining pharmacogenomic traits, including drug metabolism, efficacy, and toxicity. RESULTS Application of GWAS to pharmacogenomic outcomes presents unique challenges and opportunities. CONCLUSION In the current review, we discuss the potential promises and potential caveats of this approach specifically as it relates to pharmacogenomic studies. Concerns with study design, power and sample size, and analysis are reviewed. We further examine the features of successful pharmacogenomic GWAS, and describe consortia efforts that are likely to expand the reach of pharmacogenomic GWAS in the future.
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27
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Riccardi LN, Lanzellotto R, Falconi M, Ceccardi S, Bini C, Pelotti S. Development of a tetraplex PCR assay for CYP2D6 genotyping in degraded DNA samples. J Forensic Sci 2013; 59:690-5. [PMID: 24313823 DOI: 10.1111/1556-4029.12358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 01/28/2013] [Accepted: 02/09/2013] [Indexed: 11/26/2022]
Abstract
CYP2D6 polymorphism analysis is gaining increasing interest in forensic pharmacogenetics. Nevertheless, DNA recovered from forensic samples could be of poor quality and not suitable for long polymerase chain reaction required to type CYP2D6 gene prior to SNaPshot minisequencing analysis performed to define alleles with different enzymatic activity. We developed and validated following the guidelines of the Scientific Working Group on DNA Analysis Methods a tetraplex PCR yielding four amplicons of 597, 803, 1142, and 1659 bp encompassing the entire CYP2D6 gene to analyze eleven SNP positions by SNaPshot minisequencing. Concordance, sensitivity, and specificity were assessed. The method, applied to thirty-two forensic samples failed to amplify with long PCR, allowed the amplification of CYP2D6 gene in 62.5% of degraded samples. The new tetraplex PCR appears a suitable method for CYP2D6 analysis in forensic pharmacogenetics.
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Affiliation(s)
- Laura N Riccardi
- Department of Medical and Surgical Sciences, Institute of Legal Medicine, University of Bologna, via Irnerio, 49, 40126, Bologna, Italy
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28
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Yee MM, Josephson C, Hill CE, Harrington R, Castillejo MI, Ramjit R, Osunkwo I. Cytochrome P450 2D6 polymorphisms and predicted opioid metabolism in African American children with sickle cell disease. J Pediatr Hematol Oncol 2013; 35:e301-5. [PMID: 23619115 PMCID: PMC3762954 DOI: 10.1097/mph.0b013e31828e52d2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The opioid medications codeine and hydrocodone, commonly prescribed in sickle cell disease (SCD), require metabolic conversion by cytochrome P450 2D6 (CYP2D6) to morphine and hydromorphone, respectively, to exert their analgesic effects. The CYP2D6 gene is highly polymorphic, with variant alleles that result in decreased, absent, or ultrarapid enzyme activity. Seventy-five children with SCD were tested for CYP2D6 polymorphisms, and metabolic phenotypes were inferred from the genotypes. The most common variant alleles were CYP2D6*2 (normal activity, 28.7%), CYP2D6*17 (reduced activity, 17.3%), CYP2D6*5 (gene deletion, 8.7%), and CYP2D6*4 (absent function, 8.0%). Normal/extensive metabolizer genotypes were found in 28/75 (37.5%), intermediate metabolism in 33/75 (44.0%), poor metabolism in 4/75 (5.3%), ultrarapid metabolism in 3/75 (4.0%), indeterminate in 6/75 (8.0%). Allele frequencies did not vary significantly among different hemoglobin genotypes. Identification of variant CYP2D6 genotypes may identify individuals with altered metabolism and therefore altered analgesic response to codeine and hydrocodone, thus providing a personalized medicine approach to treatment of pain in SCD. Further pharmacokinetic and pharmacodynamic studies are needed to define the relationship of CYP2D6 and other gene polymorphisms to individual opioid effect in SCD.
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Affiliation(s)
- Marianne McPherson Yee
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta
- Department of Pediatrics, Hematology/Oncology, Emory University, Atlanta, GA
| | - Cassandra Josephson
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta
- Department of Pediatrics, Hematology/Oncology, Emory University, Atlanta, GA
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA
| | - Charles E. Hill
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA
| | | | | | - Ruan Ramjit
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA
| | - Ifeyinwa Osunkwo
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta
- Department of Pediatrics, Hematology/Oncology, Emory University, Atlanta, GA
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29
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Abstract
Cytochrome P450 2D6 (CYP2D6) plays an important role in the metabolism and bioactivation of about 25% of clinically used drugs including many antidepressants, antipsychotics and opioids. CYP2D6 activity is highly variably ranging from no activity in so-called poor metabolizers to ultrarapid metabolism at the other end of the extreme of the activity distribution. A large portion of this variability can be explained by the highly polymorphic nature of the CYP2D6 gene locus for which > 100 variants and subvariants identified to date. Allele frequencies vary markedly between ethnic groups; some have exclusively or predominantly only been observed in certain populations. Pharmacogenetic testing holds the promise of individualizing drug therapy by identifying patients with CYP2D6 diplotypes that puts them at an increased risk of experiencing dose-related adverse events or therapeutic failure. Inferring a patient's CYP2D6 metabolic capacity, or phenotype, however, is a challenging task due to the complexity of the CYP2D6 gene locus. Allelic variation includes SNPs, small insertions and deletions, gene copy number variation and rearrangements with CYP2D7, a highly related non-functional gene. This review provides a summary of the intricacies of CYP2D6 variation and genotype analysis, knowledge that is invaluable for the translation of genotype into clinically useful information.
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Affiliation(s)
- Andrea Gaedigk
- Children's Mercy Hospital and Clinics, Division of Clinical Pharmacology and Innovative Therapeutics , Kansas City, Missouri , USA
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Blake CM, Kharasch ED, Schwab M, Nagele P. A meta-analysis of CYP2D6 metabolizer phenotype and metoprolol pharmacokinetics. Clin Pharmacol Ther 2013; 94:394-9. [PMID: 23665868 PMCID: PMC3818912 DOI: 10.1038/clpt.2013.96] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 05/01/2013] [Indexed: 12/16/2022]
Abstract
Metoprolol, a commonly prescribed beta-blocker, is primarily metabolized by cytochrome P450 2D6 (CYP2D6), an enzyme with substantial genetic heterogeneity. Several smaller studies have shown that metoprolol pharmacokinetics is influenced by CYP2D6 genotype and metabolizer phenotype. To increase robustness of metoprolol pharmacokinetic estimates, a systematic review and meta-analysis of pharmacokinetic studies that administered a single oral dose of immediate release metoprolol was performed. Pooled analysis (n= 264) demonstrated differences in peak plasma metoprolol concentration, area under the concentration-time curve, elimination half-life, and apparent oral clearance that were 2.3-, 4.9-, 2.3-, and 5.9-fold between extensive and poor metabolizers, respectively, and 5.3-, 13-, 2.6-, and 15-fold between ultra-rapid and poor metabolizers (all p<0.001). Enantiomer-specific analysis revealed genotype-dependent enantio-selective metabolism, with nearly 40% greater R- vs S-metoprolol metabolism in ultra-rapid and extensive metabolizers. This study demonstrates a marked effect of CYP2D6 metabolizer phenotype on metoprolol pharmacokinetics and confirms enantiomer specific metabolism of metoprolol.
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Affiliation(s)
- C M Blake
- Division of Clinical and Translational Research, Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA
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Ma JD, Nafziger AN, Bertino JS. Genetic Polymorphisms of Cytochrome P450 Enzymes and the Effect on Interindividual, Pharmacokinetic Variability in Extensive Metabolizers. J Clin Pharmacol 2013; 44:447-56. [PMID: 15102864 DOI: 10.1177/0091270004264642] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Genetic polymorphisms of cytochrome P450 (CYP) enzymes are one of the factors that contribute to the pharmacokinetic (PK) variability of drugs. PK variability is observed in the bimodal distribution between extensive metabolizers (EMs) and poor metabolizers (PMs). PK variability may also exist between individuals genotyped as homozygous EMs and heterozygous EMs. This may carry implications for drug dosing and drug response (e.g., risk of therapeutic failure or drug toxicity). Studies have reported significant PK differences between homozygous and heterozygous EMs. Some literature suggests that this distinction may be of clinical relevance. Due to study design limitations and data that are either sparse or conflicting, generalizations regarding the potential impact of the CYP genotype, within EMs, are difficult. Optimally designed clinical trials are needed. This review evaluates the potential impact of CYP genetic polymorphisms on interindividual PK variability of drugs within an EM population.
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Affiliation(s)
- Joseph D Ma
- Clinical Pharmacology Research Center, Bassett Healthcare, One Atwell Road, Cooperstown, NY 13326-1394, USA
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Sosa-Macías M, Elizondo G, Flores-Pérez C, Flores-Pérez J, Bradley-Alvarez F, Alanis-Bañuelos RE, Lares-Asseff I. CYP2D6Genotype and Phenotype in Amerindians of Tepehuano Origin and Mestizos of Durango, Mexico. J Clin Pharmacol 2013; 46:527-36. [PMID: 16638736 DOI: 10.1177/0091270006287586] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Although the drug-metabolizing enzyme CYP2D6 has been studied extensively in subjects of differing ethnicities, limited CYP2D6 pharmacogenetic data are available for the Amerindian population and Mestizos of Mexico. Dextromethorphan hydroxylation phenotype was studied in Tepehuano Amerindian (n = 58) and Mestizo (n = 88) subjects, and 195 individuals (85 Tepehuano Amerindians and 110 Mestizos) were genotyped by polymerase chain reaction-restriction fragment length polymorphism methods to identify the frequencies of the CYP2D6*3, *4, *6, and *10 alleles. Tepehuano Amerindian subjects lacked the poor metabolizer (PM) phenotype, whereas in Mestizos the PM phenotype frequency was 6.8%. The CYP2D6*3, *6, and *10 alleles were not found in Tepehuano Amerindians. The CYP2D6*4 allele had a low frequency (0.006) in this Amerindian group. In the Mestizo group, the CYP2D6*3, *4, and *10 alleles had frequencies of 0.009, 0.131, and 0.023, respectively. The CYP2D6*6 allele was not found in Mestizos. The genotype-phenotype association was strongly statistically significant (r(2) = .45; P = .005) in Mestizos. The Tepehuano population was found to have a low phenotypic and genotypic CYP2D6 diversity and differed from other Amerindian groups. On the other hand, the frequencies of the CYP2D6 variant alleles in Mestizos were similar to those reported for whites.
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Affiliation(s)
- Martha Sosa-Macías
- Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional del IPN Unidad Durango, CIIDIR-IPN, México
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Bezirtzoglou EEV. Intestinal cytochromes P450 regulating the intestinal microbiota and its probiotic profile. MICROBIAL ECOLOGY IN HEALTH AND DISEASE 2012; 23:18370. [PMID: 23990816 PMCID: PMC3747728 DOI: 10.3402/mehd.v23i0.18370] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 08/06/2012] [Accepted: 08/17/2012] [Indexed: 12/29/2022]
Abstract
Cytochromes P450 (CYPs) enzymes metabolize a large variety of xenobiotic substances. In this vein, a plethora of studies were conducted to investigate their role, as cytochromes are located in both liver and intestinal tissues. The P450 profile of the human intestine has not been fully characterized. Human intestine serves primarily as an absorptive organ for nutrients, although it has also the ability to metabolize drugs. CYPs are responsible for the majority of phase I drug metabolism reactions. CYP3A represents the major intestinal CYP (80%) followed by CYP2C9. CYP1A is expressed at high level in the duodenum, together with less abundant levels of CYP2C8-10 and CYP2D6. Cytochromes present a genetic polymorphism intra- or interindividual and intra- or interethnic. Changes in the pharmacokinetic profile of the drug are associated with increased toxicity due to reduced metabolism, altered efficacy of the drug, increased production of toxic metabolites, and adverse drug interaction. The high metabolic capacity of the intestinal flora is due to its enormous pool of enzymes, which catalyzes reactions in phase I and phase II drug metabolism. Compromised intestinal barrier conditions, when rupture of the intestinal integrity occurs, could increase passive paracellular absorption. It is clear that high microbial intestinal charge following intestinal disturbances, ageing, environment, or food-associated ailments leads to the microbial metabolism of a drug before absorption. The effect of certain bacteria having a benefic action on the intestinal ecosystem has been largely discussed during the past few years by many authors. The aim of the probiotic approach is to repair the deficiencies in the gut flora and establish a protective effect. There is a tentative multifactorial association of the CYP (P450) cytochrome role in the different diseases states, environmental toxic effects or chemical exposures and nutritional status.
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Affiliation(s)
- Eugenia Elefterios Venizelos Bezirtzoglou
- Laboratory of Microbiology, Biotechnology and Hygiene, Department of Food Science, Faculty of Agricultural Development, Democritus University of Thrace, Orestiada, Greece
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Vuilleumier PH, Stamer UM, Landau R. Pharmacogenomic considerations in opioid analgesia. PHARMACOGENOMICS & PERSONALIZED MEDICINE 2012; 5:73-87. [PMID: 23226064 PMCID: PMC3513230 DOI: 10.2147/pgpm.s23422] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Indexed: 12/25/2022]
Abstract
Translating pharmacogenetics to clinical practice has been particularly challenging in the context of pain, due to the complexity of this multifaceted phenotype and the overall subjective nature of pain perception and response to analgesia. Overall, numerous genes involved with the pharmacokinetics and dynamics of opioids response are candidate genes in the context of opioid analgesia. The clinical relevance of CYP2D6 genotyping to predict analgesic outcomes is still relatively unknown; the two extremes in CYP2D6 genotype (ultrarapid and poor metabolism) seem to predict pain response and/or adverse effects. Overall, the level of evidence linking genetic variability (CYP2D6 and CYP3A4) to oxycodone response and phenotype (altered biotransformation of oxycodone into oxymorphone and overall clearance of oxycodone and oxymorphone) is strong; however, there has been no randomized clinical trial on the benefits of genetic testing prior to oxycodone therapy. On the other hand, predicting the analgesic response to morphine based on pharmacogenetic testing is more complex; though there was hope that simple genetic testing would allow tailoring morphine doses to provide optimal analgesia, this is unlikely to occur. A variety of polymorphisms clearly influence pain perception and behavior in response to pain. However, the response to analgesics also differs depending on the pain modality and the potential for repeated noxious stimuli, the opioid prescribed, and even its route of administration.
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Affiliation(s)
- Pascal H Vuilleumier
- Klinik für Anästhesiologie und Schmerztherapie, Inselspital Universität Bern, Switzerland
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Andresen H, Augustin C, Streichert T. Toxicogenetics--cytochrome P450 microarray analysis in forensic cases focusing on morphine/codeine and diazepam. Int J Legal Med 2012; 127:395-404. [PMID: 22899355 DOI: 10.1007/s00414-012-0759-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Accepted: 08/03/2012] [Indexed: 01/10/2023]
Abstract
Genetic polymorphisms in cytochrome P 450 (CYP) enzymes could lead to a phenotype with altered enzyme activity. In pharmacotherapy, genotype-based dose recommendations achieved great importance for several drugs. In our pilot study, we ask if these genetic tests should be applied to forensic problems as a matter of routine. Starting from 2004 through 2008, we screened routine cases for samples where the relation of parent compound to metabolite(s) (P/M ratio), particularly morphine to codeine ratios and diazepam to its metabolites, was noticeable or not consistent with the information provided by the defendants. We found 11 samples with conspicuous results. These were analyzed for polymorphisms of the CYP 2D6 and 2C19 genes using the Roche AmpliChip Cytochrome P450 Genotyping test. If not previously conducted, a general unknown analysis by gas chromatography/mass spectrometry (GC/MS) was additionally carried out. For CYP 2D6, we found two cases with the genotype poor metabolizer (PM), three cases with heterozygote extensive metabolizer genotype classified as an intermediate metabolizer (IM) with probably reduced enzyme activities, but no ultrarapid metabolizer genotype. For CYP 2C19, two cases were characterized as IM phenotypes, with no PM found. Once we achieved no appropriate amounts of DNA, one case was excluded after GC/MS analysis. Only in one case could the polymorphism clearly explain the changes in drug metabolism. More frequently, a drug-drug interaction was thought to have a stronger impact. Additionally, our results suggest that IM genotypes may be more relevant than previously suspected. With respect to the small number of cases in which we thought a genotyping would be helpful, we conclude that the overall relevance of toxicogenetics in forensic problems is moderate. However, in some individual cases, a genotyping may provide new insight.
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Affiliation(s)
- H Andresen
- Institute of Legal Medicine, Forensic Toxicology, University Medical Center Hamburg-Eppendorf, Butenfeld 34, 22529, Hamburg, Germany.
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Wesmiller SW, Henker RA, Sereika SM, Donovan HS, Meng L, Gruen GS, Tarkin IS, Conley YP. The association of CYP2D6 genotype and postoperative nausea and vomiting in orthopedic trauma patients. Biol Res Nurs 2012; 15:382-9. [PMID: 22718526 DOI: 10.1177/1099800412449181] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The CYP2D6 gene encodes for an enzyme that is involved in the metabolism of more than 25% of all medications, including many opioids and antiemetics. It may contribute to the risk of postoperative nausea and vomiting (PONV), a common surgical complication. However, little research has been conducted in this area. The purpose of this study was to explore the association of CYP2D6 genotypes with PONV in adult surgical trauma patients. Data from 112 patients (28% female) with single extremity fractures, aged 18-70 years, were analyzed. PONV was defined as present if patients reported nausea, were observed vomiting, or received medication for PONV. Saliva samples collected for DNA extraction and Taqman(®) allele discrimination and quantitative real time polymerase chain reaction (qRT-PCR) were used to collect genotype data that were then used to assign CYP2D6 phenotype classification. The incidence of PONV was 38% in the postanesthesia care unit and increased to 50% when assessed at 48 hr. CYP2D6 classification results were 7 (6%) poor metabolizers, 34 (30%) intermediate metabolizers, and 71 (63%) extensive metabolizers. No ultrarapid metabolizers were identified. Patients who were classified as poor metabolizers had less PONV and higher pain scores. Gender and history of PONV, but not smoking, were also significant risk factors. Findings suggest variability in CYP2D6 impacts susceptibility to PONV.
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Nagele P. Perioperative genomics. Best Pract Res Clin Anaesthesiol 2012; 25:549-55. [PMID: 22099920 DOI: 10.1016/j.bpa.2011.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 09/15/2011] [Indexed: 11/28/2022]
Abstract
Since the completion of the Human Genome Project 10 years ago, the world has witnessed an incredible progress in human genetics and genomics.(1) This progress was largely driven by the availability of better, faster and cheaper sequencing technology.(2) While it took more than 10 years and more than 1 billion dollars to complete the Human Genome Project,(3-5) an individual in the year 2011 can have his whole genome sequenced within a week for less than $30,000. With cheaper and faster sequencing came a wealth of novel discoveries which makes it timely to review how these newly found insights into the human genome are relevant for perioperative medicine. This article summarises the basics of genetic inheritance, the human genome and modern sequencing methods, as well as genetic variation and how this knowledge may be applied to patient care and research in the perioperative setting.
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Affiliation(s)
- Peter Nagele
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Stamer UM, Bayerer B, Stüber F. Genetics and variability in opioid response. Eur J Pain 2012; 9:101-4. [PMID: 15737794 DOI: 10.1016/j.ejpain.2004.05.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2004] [Accepted: 05/17/2004] [Indexed: 10/26/2022]
Abstract
The human genome project has revealed data on genomic variation which may influence the pharmacological responses. In pain therapy, the genetic background influencing the efficacy of opioid therapy is of special interest. Screening for variations in expression of drug metabolizing enzymes has been suggested as a potential tool for improving patient therapy. CYP2D6 genetic variability is supposed to be a major factor of adverse drug reaction, possibly influencing hospital stay and total costs. Further candidate genes involved in pain perception, pain processing and pain management like opioid receptors, transporters and other targets of pharmacotherapy are under investigation. Aspects of genetic differences influencing efficacy, side effects and adverse outcome of pharmacotherapy will be of importance for future pain management.
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Affiliation(s)
- Ulrike M Stamer
- Department of Anaesthesiology and Intensive Care Medicine, Rheinische Friedrich-Wilhelms-Universität Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany.
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40
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Lee IS, Kim D. Polymorphic metabolism by functional alterations of human cytochrome P450 enzymes. Arch Pharm Res 2011; 34:1799-816. [PMID: 22139682 DOI: 10.1007/s12272-011-1103-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 08/24/2011] [Indexed: 10/14/2022]
Abstract
The study of cytochrome P450 pharmacogenomics is of particular interest because of its promise in the development of rational means to optimize drug therapy with respect to patient's genotype to ensure maximum efficacy with minimal adverse effects. Drug metabolizing P450 enzymes are polymorphic and are the main phase I enzymes responsible for the metabolism of clinical drugs. Therefore, polymorphisms in the P450s have the most impact on the fate of clinical drugs in phase I metabolism since almost 80% of drugs in use today are metabolized by these enzymes. Predictive genotyping for P450 enzymes for a more effective therapy will be routine for specific drugs in the future. In this review, we discuss the current knowledge of polymorphic metabolism by functional alterations in nonsynonymous SNPs of P450 1A2, 2A6, 2C8, 2C9, 2C19, 2D6, and 3A4 enzymes.
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Affiliation(s)
- Im-Soon Lee
- Department of Biological Sciences and Center for Biotechnology Research in UBITA, Konkuk University, Seoul 143-701, Korea
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Abstract
Perioperative myocardial infarction is a common and potentially fatal complication after noncardiac surgery, particular among patients with cardiovascular risk factors. β-blockers have been considered a mainstay in prevention and treatment of perioperative myocardial infarction, yet recent evidence suggests that β-blockers may have an unfavorable risk profile in this setting, and the use has become controversial. What seems conspicuously absent from the current discussion is the appreciation of how much interindividual genetic variation influences the clinical response to β-blocker therapy. Genetic variation in the adrenergic signaling pathway is common, and has a major impact on adrenergic receptor function and β-blocker efficacy in other cardiovascular diseases, such as heart failure and hypertension. Genetic variation in the cytochrome P450 2D6, or CYP2D6, enzyme, which is responsible for the metabolism of most β-blockers, is also important and can lead to poor metabolizing of β-blockers (potential toxicity) or their ultra-rapid degradation (decreased efficacy). Here, we review the molecular, cellular, and physiologic consequences of polymorphisms in the adrenergic signaling pathway and CYP2D6 gene, and show that these are likely relevant factors influencing efficacy, safety, and toxicity of β-blocker therapy in prevention and treatment of perioperative myocardial infarction.
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Affiliation(s)
- Peter Nagele
- Division of Clinical and Translational Research, Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
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Abstract
The cytochrome P450 (CYP) superfamily is one of the most important groups of enzymes involved in drug metabolism. It is responsible for the metabolism of a large number of drugs. Many CYP isoforms are expressed polymorphically, and catalytic alterations of allelic variant proteins can affect the metabolic activities of many drugs. The CYP2D6, CYP2C9, CYP2C19, and CYP2B6 genes are particularly polymorphic, whereas CYP1A1, CYP1A2, CYP2E1, and CYP3A4 are relatively well conserved without common functional polymorphisms. In vitro studies using cDNA expression systems are useful tools for evaluating functional alterations of the allelic variants of CYP, particularly for low-frequency alleles. Recombinant CYPs have been successfully expressed in bacteria, yeast, baculoviruses, and several mammalian cells. Determination of CYP variant-mediated kinetic parameters (Km and Vmax) in vitro can be useful for predicting drug dosing and clearance in humans. This review focuses on the advantages and disadvantages of the various cDNA-expression systems used to determine the kinetic parameters for CYP allelic variants, the methods for determining the kinetic parameters, and the findings of in vitro studies on highly polymorphic CYPs, including CYP2D6, CYP2C9, CYP2C19, and CYP2B6.
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Affiliation(s)
- Masahiro Hiratsuka
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan.
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Suwannasri P, Thongnoppakhun W, Pramyothin P, Assawamakin A, Limwongse C. Combination of multiplex PCR and DHPLC-based strategy for CYP2D6 genotyping scheme in Thais. Clin Biochem 2011; 44:1144-1152. [DOI: 10.1016/j.clinbiochem.2011.06.985] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 06/01/2011] [Accepted: 06/26/2011] [Indexed: 10/18/2022]
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Razmkhah F, Pazhakh V, Zaker F, Atashrazm F, Sheikhi M. Frequency of CYP1A1*2C Polymorphism in Patients with Leukemia in the Iranian Population. Lab Med 2011. [DOI: 10.1309/lm337jwosvnehpui] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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Leppert W. CYP2D6 in the Metabolism of Opioids for Mild to Moderate Pain. Pharmacology 2011; 87:274-85. [DOI: 10.1159/000326085] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 02/14/2011] [Indexed: 11/19/2022]
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Kleine-Brueggeney M, Musshoff F, Stuber F, Stamer UM. Pharmacogenetics in palliative care. Forensic Sci Int 2010; 203:63-70. [DOI: 10.1016/j.forsciint.2010.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Relationship between drug-induced interstitial lung diseases and cytochrome P450 polymorphisms. Curr Opin Pulm Med 2010; 16:496-502. [PMID: 20592596 DOI: 10.1097/mcp.0b013e32833c06f1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Interstitial lung disease and especially drug-induced interstitial lung disease can occur as a cause of drug(s) or drug-drug interactions. In this review we summarize the possible role of cytochrome P450 (CYP) enzymes in drug-induced interstitial lung disease. RECENT FINDINGS The CYP enzyme family plays an important role in the metabolism of all sorts of ingested, injected or inhaled xenobiotic substances. Although the liver is considered to be the major metabolism site of CYP enzymes, in recent years more CYP isoforms have been detected in lung tissue. Polymorphisms in these CYP genes can influence the metabolic activity of the subsequent enzymes, which in turn may lead to localized (toxic) reactions and tissue damage. SUMMARY Drug toxicity can be the consequence of no or very poor enzyme activity, especially if no other metabolic route is available. In the case of reduced enzyme activity, dose reduction or prescribing an alternative drug metabolized by a different, unaffected CYP enzyme is recommended to prevent toxic side effects. Therefore, knowing a patient's CYP profile before drug prescription could be a way to prevent drug-induced interstitial lung disease. Moreover, it might be helpful in explaining serious adverse effects from inhaled, injected or ingested xenobiotic substances.
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Khalsa JH, Elkashef A. Drug interactions between antiretroviral medications and medications used in the treatment of drug addiction: research needs. Am J Addict 2010; 19:96-100. [PMID: 20132126 DOI: 10.1111/j.1521-0391.2009.00010.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Today substance dependence is one of the major public health problems in the world with millions of people abusing legal and illegal drugs. In addition, almost one-third of the world's population suffers with one or more infections. Both drugs of abuse and infections are associated with serious medical and health consequences, some of which may be exacerbated by the occurrence of pharmacokinetic and/or pharmacodynamic interactions between medications used in the treatment of these conditions when they co-occur. This review briefly discusses issues surrounding clinical management related to drug interactions experienced by substance abusing patients. The emphasis of this paper is on the research needed to further study the extent, nature, and underlying molecular/genetic mechanism(s) of interactions between drugs of abuse, medications used in the treatment of drug addiction, and co-occurring infections.
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Affiliation(s)
- Jag H Khalsa
- Division of Pharmacotherapies and Medical Consequences of Drug Abuse, National Institute on Drug Abuse, Bethesda, MD 20892, USA.
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50
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Li-Wan-Po A, Girard T, Farndon P, Cooley C, Lithgow J. Pharmacogenetics of CYP2C19: functional and clinical implications of a new variant CYP2C19*17. Br J Clin Pharmacol 2010; 69:222-30. [PMID: 20233192 DOI: 10.1111/j.1365-2125.2009.03578.x] [Citation(s) in RCA: 189] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
AIMS Cytochrome P450 2C19 metabolizes many important drugs. In 2006, a variant allele (CYP2C19*17) associated with increased activity was discovered, but its likely clinical significance is controversial. Investigators disagree about the phenotype to be assigned to the two CYP2C19*17 genotypes. The aim of this study was to provide a critical summary, helpful to prescribers. METHODS We searched MEDLINE for papers on the allele from 2006 and then undertook historical searches through the reference lists of papers retrieved. The relevant information was critically assessed and summarized. RESULTS CYP2C19*17 was associated with increased enzymic activity. Substrates studied were omeprazole, pantoprazole, escitalopram, sertraline, voriconazole, tamoxifen and clopidogrel. Most studies used pharmacokinetic variables as outcome measure. For clopidogrel, activated by CYP2C19, pharmacodynamic consequences focused on platelet aggregation. While for most pharmacokinetic parameters of the substrates studied the average value was altered, the range of values showed mostly complete overlap for CYP2C19*1/*17 heterozygotes and wild-type homozygotes. Even for CYP2C19*17 homozygotes, the absolute effect was modest compared with the effect of previously identified loss-of-function alleles. In Helicobacter pylori eradication CYP2C19*2 carriage was associated with an altered eradication rate (odds ratio 4.20, 95% confidence interval 1.23, 16.44) relative to the wild-type, but CYP2C19*17 homozygosity was not. Prevalence of the variant allele was typically <5% in Asians and about four times higher in White and African populations. CONCLUSIONS Assignment of CYP2C19*17 homozygotes as extensive metabolizers rather than ultrarapid metabolizers is adequate. CYP2C19*17 genotyping is unlikely to have clinical utility except for drugs with very narrow therapeutic indices.
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Affiliation(s)
- Alain Li-Wan-Po
- National Genetics Education and Development Centre, C/o Birmingham Women's Hospital, UK.
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