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Carr TF, Fajt ML, Kraft M, Phipatanakul W, Szefler SJ, Zeki AA, Peden DB, White SR. Treating asthma in the time of COVID. J Allergy Clin Immunol 2023; 151:809-817. [PMID: 36528110 PMCID: PMC9749385 DOI: 10.1016/j.jaci.2022.12.800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/30/2022] [Accepted: 12/12/2022] [Indexed: 12/15/2022]
Abstract
The Precision Interventions for Severe and/or Exacerbation-Prone Asthma clinical trials network is actively assessing novel treatments for severe asthma during the coronavirus disease (COVID-19) pandemic and has needed to adapt to various clinical dilemmas posed by the COVID-19 pandemic. Pharmacologic interactions between established asthma therapies and novel drug interventions for COVID-19 infection, including antivirals, biologics, and vaccines, have emerged as a critical and unanticipated issue in the clinical care of asthma. In particular, impaired metabolism of some long-acting beta-2 agonists by the cytochrome P4503A4 enzyme in the setting of antiviral treatment using ritonavir-boosted nirmatrelvir (NVM/r, brand name Paxlovid) may increase risk for adverse cardiovascular events. Although available data have documented the potential for such interactions, these issues are largely unappreciated by clinicians who treat asthma, or those dispensing COVID-19 interventions in patients who happen to have asthma. Because these drug-drug interactions have not previously been relevant to patient care, clinicians have had no guidance on management strategies to reduce potentially serious interactions between treatments for asthma and COVID-19. The Precision Interventions for Severe and/or Exacerbation-Prone Asthma network considered the available literature and product information, and herein share our considerations and plans for treating asthma within the context of these novel COVID-19-related therapies.
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Affiliation(s)
- Tara F Carr
- Asthma and Airway Disease Research Center, University of Arizona, Tucson
| | - Merritt L Fajt
- Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh, Pittsburgh
| | - Monica Kraft
- Samuel Bronfman Department of Medicine, Icahn School of Medicine at Mount Sinai, New York
| | - Wanda Phipatanakul
- Division of Allergy and Immunology, Department of Pediatrics, Boston Children's Hospital, Boston
| | - Stanley J Szefler
- The University of Colorado School of Medicine and Children's Hospital Colorado, Department of Pediatrics, The Breathing Institute, Aurora
| | - Amir A Zeki
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, University of California, Davis School of Medicine, UC Davis Lung Center, Sacramento
| | - David B Peden
- Division of Allergy and Immunology, Department of Pediatrics, University of North Carolina, Chapel Hill
| | - Steven R White
- Department of Medicine, the University of Chicago, Chicago.
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Kukal S, Thakran S, Kanojia N, Yadav S, Mishra MK, Guin D, Singh P, Kukreti R. Genic-intergenic polymorphisms of CYP1A genes and their clinical impact. Gene 2023; 857:147171. [PMID: 36623673 DOI: 10.1016/j.gene.2023.147171] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/16/2022] [Accepted: 01/03/2023] [Indexed: 01/08/2023]
Abstract
The humancytochrome P450 1A (CYP1A) subfamily genes, CYP1A1 and CYP1A2, encoding monooxygenases are critically involved in biotransformation of key endogenous substrates (estradiol, arachidonic acid, cholesterol) and exogenous compounds (smoke constituents, carcinogens, caffeine, therapeutic drugs). This suggests their significant involvement in multiple biological pathways with a primary role of maintaining endogenous homeostasis and xenobiotic detoxification. Large interindividual variability exist in CYP1A gene expression and/or catalytic activity of the enzyme, which is primarily due to the existence of polymorphic alleles which encode them. These polymorphisms (mainly single nucleotide polymorphisms, SNPs) have been extensively studied as susceptibility factors in a spectrum of clinical phenotypes. An in-depth understanding of the effects of polymorphic CYP1A genes on the differential metabolic activity and the resulting biological pathways is needed to explain the clinical implications of CYP1A polymorphisms. The present review is intended to provide an integrated understanding of CYP1A metabolic activity with unique substrate specificity and their involvement in physiological and pathophysiological roles. The article further emphasizes on the impact of widely studied CYP1A1 and CYP1A2 SNPs and their complex interaction with non-genetic factors like smoking and caffeine intake on multiple clinical phenotypes. Finally, we attempted to discuss the alterations in metabolism/physiology concerning the polymorphic CYP1A genes, which may underlie the reported clinical associations. This knowledge may provide insights into the disease pathogenesis, risk stratification, response to therapy and potential drug targets for individuals with certain CYP1A genotypes.
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Affiliation(s)
- Samiksha Kukal
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Sarita Thakran
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Neha Kanojia
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Saroj Yadav
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Manish Kumar Mishra
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Department of Biotechnology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042, India
| | - Debleena Guin
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Department of Biotechnology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042, India
| | - Pooja Singh
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Ritushree Kukreti
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
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Wedagedera JR, Afuape A, Chirumamilla SK, Momiji H, Leary R, Dunlavey M, Matthews R, Abduljalil K, Jamei M, Bois FY. Population PBPK modeling using parametric and nonparametric methods of the Simcyp Simulator, and Bayesian samplers. CPT Pharmacometrics Syst Pharmacol 2022; 11:755-765. [PMID: 35385609 PMCID: PMC9197540 DOI: 10.1002/psp4.12787] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 03/01/2022] [Accepted: 03/07/2022] [Indexed: 11/23/2022] Open
Abstract
Physiologically‐based pharmacokinetic (PBPK) models usually include a large number of parameters whose values are obtained using in vitro to in vivo extrapolation. However, such extrapolations can be uncertain and may benefit from inclusion of evidence from clinical observations via parametric inference. When clinical interindividual variability is high, or the data sparse, it is essential to use a population pharmacokinetics inferential framework to estimate unknown or uncertain parameters. Several approaches are available for that purpose, but their relative advantages for PBPK modeling are unclear. We compare the results obtained using a minimal PBPK model of a canonical theophylline dataset with quasi‐random parametric expectation maximization (QRPEM), nonparametric adaptive grid estimation (NPAG), Bayesian Metropolis‐Hastings (MH), and Hamiltonian Markov Chain Monte Carlo sampling. QRPEM and NPAG gave consistent population and individual parameter estimates, mostly agreeing with Bayesian estimates. MH simulations ran faster than the others methods, which together had similar performance.
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Affiliation(s)
| | | | | | | | - Robert Leary
- CERTARA UK Limited, Simcyp Division, Sheffield, UK
| | | | | | | | - Masoud Jamei
- CERTARA UK Limited, Simcyp Division, Sheffield, UK
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Development of Physiologically Based Pharmacokinetic Model and Assessment of the Impact of Renal Underdevelopment in Preterm Infants on the Pharmacokinetics of Aminophylline. J Pharmacol Pharmacother 2022. [DOI: 10.1177/0976500x221080209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Objective: To develop a physiologically based pharmacokinetic (PBPK) model for individualization of the dosing regimen considering the physiological requirements of these preterm neonates. Methods: The study comprised preterm newborns with fewer than 34 weeks of gestation and six apneic episodes in 24 h. A PBPK model was created using PK-SIM (version 9, update 1, GitHub, San Francisco, CA, USA). A PBPK model is built using a typical loading dosage of 5 mg/kg and a maintenance dose of 1.5 mg/kg. Based on the verified base model, a PBPK model representing renal underdevelopment based on nRIFLE/pRIFLE categorization was developed. Results: The PK parameters of Aminophylline were computed using the PBPK model. As per the model prediction, T1/2 and area under the curve reduced as postnatal age increased, and in the event of renal underdevelopment, even while C max for patients under R (RISK), I (injury) was within the therapeutic range; it was greater compared to preterm without any renal complications. Mean C max (mol/L) was 59.53 and for R, I, and F (FAILURE) categories the values were 83.04, 99.69, and 126.98, respectively. Conclusion: The model was created using appropriate drug, study subject, and dosage protocol inputs. The established PBPK model could help in individualizing aminophylline dose in preterm babies.
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Electrochemical Sensor Based on CuO Nanoparticles Fabricated From Copper Wire Recycling-loaded Carbon Paste Electrode for Excellent Detection of Theophylline in Pharmaceutical Formulations. Electrocatalysis (N Y) 2022. [DOI: 10.1007/s12678-021-00698-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abduljalil K, Gardner I, Jamei M. Application of a Physiologically Based Pharmacokinetic Approach to Predict Theophylline Pharmacokinetics Using Virtual Non-Pregnant, Pregnant, Fetal, Breast-Feeding, and Neonatal Populations. Front Pediatr 2022; 10:840710. [PMID: 35652056 PMCID: PMC9150776 DOI: 10.3389/fped.2022.840710] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 04/11/2022] [Indexed: 12/23/2022] Open
Abstract
Perinatal pharmacology is influenced by a myriad of physiological variables that are changing dynamically. The influence of these covariates has not been assessed systemically. The objective of this work was to use theophylline as a model drug and to predict its pharmacokinetics before, during (including prediction of the umbilical cord level), and after pregnancy as well as in milk (after single and multiple doses) and in neonates using a physiological-based pharmacokinetic (PBPK) model. Neonatal theophylline exposure from milk consumption was projected in both normal term and preterm subjects. Predicted infant daily doses were calculated using theophylline average and maximum concentration in the milk as well as an estimate of milk consumption. Predicted concentrations and parameters from the PBPK model were compared to the observed data. PBPK predicted theophylline concentrations in non-pregnant and pregnant populations at different gestational weeks were within 2-fold of the observations and the observed concentrations fell within the 5th-95th prediction interval from the PBPK simulations. The PBPK model predicted an average cord-to-maternal plasma ratio of 1.0, which also agrees well with experimental observations. Predicted postpartum theophylline concentration profiles in milk were also in good agreement with observations with a predicted milk-to-plasma ratio of 0.68. For an infant of 2 kg consuming 150 ml of milk per day, the lactation model predicted a relative infant dose (RID) of 12 and 17% using predicted average (Cavg,ss) and maximum (Cmax,ss) concentration in milk at steady state. The maximum RID of 17% corresponds to an absolute infant daily dose of 1.4 ± 0.5 mg/kg/day. This dose, when administered as 0.233 mg/kg every 4 h, to resemble breastfeeding frequency, resulted in plasma concentrations as high as 3.9 (1.9-6.8) mg/L and 2.8 (1.3-5.3) (5th-95th percentiles) on day 7 in preterm (32 GW) and full-term neonatal populations.
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Affiliation(s)
| | - Iain Gardner
- Certara UK Limited (Simcyp Division), Sheffield, United Kingdom
| | - Masoud Jamei
- Certara UK Limited (Simcyp Division), Sheffield, United Kingdom
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Kurata Y, Muraki S, Hirota T, Araki H, Ieiri I. Reduced theophylline clearance due to hepatic congestion secondary to right heart failure - A population pharmacokinetic study. Drug Metab Pharmacokinet 2021; 41:100403. [PMID: 34619548 DOI: 10.1016/j.dmpk.2021.100403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 12/28/2022]
Abstract
Theophylline, a beneficial drug with bronchodilatory and anti-inflammatory effects, is used for the treatment of respiratory diseases. Pulmonary (PC) and hepatic congestion (HC) are secondary to the development of left- and right-sided heart failure (HF), respectively. This study aimed to evaluate the effects of PC and HC on theophylline clearance (CL) by population pharmacokinetic (PPK) analysis with consideration of the severity of HF assessed by the New York Heart Association (NYHA) functional classification. We obtained 710 minimum steady-state concentrations from 201 Japanese bronchial asthma patients with and without HF. PPK analysis was performed by NONMEM. In the analysis, the left ventricular ejection fraction, smoking (SMK), clarithromycin (CAM), sex, and age were also considered as covariates. The final model of apparent theophylline clearance (CL/F) was as follows: CL/F (L/hr/kg) = 0.0465 × 1.40SMK × 0.870CAM × 0.863HC(+)NYHA II × 0.634HC(+)NYHA III × 0.586HC(-)NYHA IV × 0.467HC(+)NYHA IV. SMK is a well-known factor that markedly enhances theophylline clearance through the induction of CYP1A enzymes, while CAM has been reported to inhibit CYP3A4. The final model indicates that HF patients with HC show reduced clearance of theophylline depending on the severity of HF. In this study, no effects of PC were observed.
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Affiliation(s)
- Yasuo Kurata
- Department of Pharmacy, Fukuoka City Hospital, Fukuoka City Hospital Organization, Local Incorporated Administrative Agency, Fukuoka, Japan.
| | - Shota Muraki
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Takeshi Hirota
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan; Department of Pharmacy, Kyushu University Hospital, Fukuoka, Japan
| | - Hiroshi Araki
- Department of Pharmacy, Fukuoka City Hospital, Fukuoka City Hospital Organization, Local Incorporated Administrative Agency, Fukuoka, Japan
| | - Ichiro Ieiri
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan; Department of Pharmacy, Kyushu University Hospital, Fukuoka, Japan
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Drug-Drug Interactions Involving Intestinal and Hepatic CYP1A Enzymes. Pharmaceutics 2020; 12:pharmaceutics12121201. [PMID: 33322313 PMCID: PMC7764576 DOI: 10.3390/pharmaceutics12121201] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/02/2020] [Accepted: 12/08/2020] [Indexed: 12/29/2022] Open
Abstract
Cytochrome P450 (CYP) 1A enzymes are considerably expressed in the human intestine and liver and involved in the biotransformation of about 10% of marketed drugs. Despite this doubtless clinical relevance, CYP1A1 and CYP1A2 are still somewhat underestimated in terms of unwanted side effects and drug–drug interactions of their respective substrates. In contrast to this, many frequently prescribed drugs that are subjected to extensive CYP1A-mediated metabolism show a narrow therapeutic index and serious adverse drug reactions. Consequently, those drugs are vulnerable to any kind of inhibition or induction in the expression and function of CYP1A. However, available in vitro data are not necessarily predictive for the occurrence of clinically relevant drug–drug interactions. Thus, this review aims to provide an up-to-date summary on the expression, regulation, function, and drug–drug interactions of CYP1A enzymes in humans.
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Differences in Theophylline Clearance Between Patients With Chronic Hepatitis and Those With Liver Cirrhosis. Ther Drug Monit 2020; 42:829-834. [PMID: 32657910 DOI: 10.1097/ftd.0000000000000787] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Theophylline, a xanthine derivative drug, is used for the treatment of respiratory diseases, such as asthma, and is primarily eliminated by hepatic metabolism. There is marked interindividual variability in theophylline clearance. Therefore, the aim of this study was to evaluate the influence of chronic hepatitis (CH), liver cirrhosis (LC), and other covariates on theophylline clearance by population pharmacokinetic (PPK) analysis. METHODS The authors retrospectively obtained 496 trough concentrations of theophylline at steady state from 226 adult patients with bronchial asthma. The liver functions of the patients were classified into 3 categories: normal hepatic function, CH, and LC. The PPK analysis was performed using the NONMEM program. CH, LC, age, smoking status, coadministration of clarithromycin (CAM), and sex were considered as covariates that affected theophylline clearance. RESULTS Theophylline clearance (CL/F per kg) was significantly influenced by CH, LC, smoking, and CAM. The final model of theophylline clearance was as follows: CL/F (L/h·kg) = 0.0484 × 1.40 × 0.861 × 0.889 × 0.557. Smoking is a well-known factor that markedly enhances CL/F through the induction of CYP1A enzymes, whereas CAM has been reported to inhibit CYP3A4. The final model for hepatic function showed that CL/F in CH and LC patients was 0.043 and 0.027 L/h/kg, respectively, and it was lower than that in patients with normal hepatic function. As theophylline clearance depends on intrinsic hepatic clearance, lower CL/F in patients with LC than in those with CH may be due to a decrease in the metabolic enzymatic capability of LC patients. CONCLUSIONS Differences exist in theophylline clearance between CH and LC patients as per the PPK analysis.
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Wang Y, Bahar MA, Jansen AME, Kocks JWH, Alffenaar JWC, Hak E, Wilffert B, Borgsteede SD. Improving antibacterial prescribing safety in the management of COPD exacerbations: systematic review of observational and clinical studies on potential drug interactions associated with frequently prescribed antibacterials among COPD patients. J Antimicrob Chemother 2020; 74:2848-2864. [PMID: 31127283 PMCID: PMC6814093 DOI: 10.1093/jac/dkz221] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 04/13/2019] [Accepted: 04/26/2019] [Indexed: 02/07/2023] Open
Abstract
Background Guidelines advise the use of antibacterials (ABs) in the management of COPD exacerbations. COPD patients often have multiple comorbidities, such as diabetes mellitus and cardiac diseases, leading to polypharmacy. Consequently, drug–drug interactions (DDIs) may frequently occur, and may cause serious adverse events and treatment failure. Objectives (i) To review DDIs related to frequently prescribed ABs among COPD patients from observational and clinical studies. (ii) To improve AB prescribing safety in clinical practice by structuring DDIs according to comorbidities of COPD. Methods We conducted a systematic review by searching PubMed and Embase up to 8 February 2018 for clinical trials, cohort and case–control studies reporting DDIs of ABs used for COPD. Study design, subjects, sample size, pharmacological mechanism of DDI and effect of interaction were extracted. We evaluated levels of DDIs and quality of evidence according to established criteria and structured the data by possible comorbidities. Results In all, 318 articles were eligible for review, describing a wide range of drugs used for comorbidities and their potential DDIs with ABs. DDIs between ABs and co-administered drugs could be subdivided into: (i) co-administered drugs altering the pharmacokinetics of ABs; and (ii) ABs interfering with the pharmacokinetics of co-administered drugs. The DDIs could lead to therapeutic failures or toxicities. Conclusions DDIs related to ABs with clinical significance may involve a wide range of indicated drugs to treat comorbidities in COPD. The evidence presented can support (computer-supported) decision-making by health practitioners when prescribing ABs during COPD exacerbations in the case of co-medication.
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Affiliation(s)
- Yuanyuan Wang
- Department of PharmacoTherapy, -Epidemiology & -Economics, Groningen Research Institute of Pharmacy, University of Groningen, Groningen, The Netherlands
| | - Muh Akbar Bahar
- Department of PharmacoTherapy, -Epidemiology & -Economics, Groningen Research Institute of Pharmacy, University of Groningen, Groningen, The Netherlands.,Faculty of Pharmacy, Hasanuddin University, Makassar, Indonesia
| | - Anouk M E Jansen
- Department of PharmacoTherapy, -Epidemiology & -Economics, Groningen Research Institute of Pharmacy, University of Groningen, Groningen, The Netherlands
| | - Janwillem W H Kocks
- Department of General Practice and Elderly Care Medicine, Groningen Research Institute for Asthma and COPD, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jan-Willem C Alffenaar
- Department of Clinical Pharmacy & Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Faculty of Medicine and Health, School of Pharmacy and Westmead Hospital, University of Sydney, Sydney, Australia
| | - Eelko Hak
- Department of PharmacoTherapy, -Epidemiology & -Economics, Groningen Research Institute of Pharmacy, University of Groningen, Groningen, The Netherlands
| | - Bob Wilffert
- Department of PharmacoTherapy, -Epidemiology & -Economics, Groningen Research Institute of Pharmacy, University of Groningen, Groningen, The Netherlands.,Department of Clinical Pharmacy & Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Sander D Borgsteede
- Department of Clinical Decision Support, Health Base Foundation, Houten, The Netherlands.,Department of Hospital Pharmacy, Erasmus University Medical Center, Rotterdam, The Netherlands
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Rasool MF, Khalid R, Imran I, Majeed A, Saeed H, Alasmari F, Alanazi MM, Alqahtani F. Investigating the Role of Altered Systemic Albumin Concentration on the Disposition of Theophylline in Adult and Pediatric Patients with Asthma by Using the Physiologically Based Pharmacokinetic Approach. Drug Metab Dispos 2020; 48:570-579. [PMID: 32393652 DOI: 10.1124/dmd.120.090969] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 04/20/2020] [Indexed: 12/18/2022] Open
Abstract
Theophylline is commonly used for the treatment of asthma and has a low hepatic clearance. The changes in plasma albumin concentration occurring in asthma may affect the exposure of theophylline. The aim of the presented work was to predict theophylline pharmacokinetics (PK) after incorporating the changes in plasma albumin concentration occurring in patients with asthma into a physiologically based pharmacokinetic (PBPK) model to see whether these changes can affect the systemic theophylline concentrations in asthma. The PBPK model was developed following a systematic model building approach using Simcyp. The predictions were performed initially in healthy adults after intravenous and oral drug administration. Only when the developed adult PBPK model had adequately predicted theophylline PK in healthy adults, the changes in plasma albumin concentrations were incorporated into the model for predicting drug exposure in patients with asthma. After evaluation of the developed model in the adult population, it was scaled to children on physiologic basis. The model evaluation was performed by using visual predictive checks and comparison of ratio of observed and predicted (Robs/Pre) PK parameters along with their 2-fold error range. The developed PBPK model has effectively described theophylline PK in both healthy and diseased populations, as Robs/Pre for all the PK parameters were within the 2-fold error limit. The predictions in patients with asthma showed that there were no significant changes in PK parameters after incorporating the changes in serum albumin concentration. The mechanistic nature of the developed asthma-PBPK model can facilitate its extension to other drugs. SIGNIFICANCE STATEMENT: Exposure of a low hepatic clearance drug like theophylline may be susceptible to plasma albumin concentration changes that occur in asthma. These changes in systemic albumin concentrations can be incorporated into a physiologically based pharmacokinetic model to predict theophylline pharmacokinetics in adult and pediatric asthma populations. The presented work is focused on predicting theophylline absorption, distribution, metabolism, and elimination in adult and pediatric asthma populations after incorporating reported changes in serum albumin concentrations to see their impact on the systemic theophylline concentrations.
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Affiliation(s)
- Muhammad Fawad Rasool
- Departments of Pharmacy Practice (M.F.R., R.K., A.M.) and Pharmacology (I.I.), Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan; Section of Pharmaceutics, University College of Pharmacy, Allama Iqbal Campus, University of the Punjab, Lahore, Pakistan (H.S.); and Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia (F.F.A., M.M.A., F.A.)
| | - Ramsha Khalid
- Departments of Pharmacy Practice (M.F.R., R.K., A.M.) and Pharmacology (I.I.), Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan; Section of Pharmaceutics, University College of Pharmacy, Allama Iqbal Campus, University of the Punjab, Lahore, Pakistan (H.S.); and Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia (F.F.A., M.M.A., F.A.)
| | - Imran Imran
- Departments of Pharmacy Practice (M.F.R., R.K., A.M.) and Pharmacology (I.I.), Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan; Section of Pharmaceutics, University College of Pharmacy, Allama Iqbal Campus, University of the Punjab, Lahore, Pakistan (H.S.); and Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia (F.F.A., M.M.A., F.A.)
| | - Abdul Majeed
- Departments of Pharmacy Practice (M.F.R., R.K., A.M.) and Pharmacology (I.I.), Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan; Section of Pharmaceutics, University College of Pharmacy, Allama Iqbal Campus, University of the Punjab, Lahore, Pakistan (H.S.); and Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia (F.F.A., M.M.A., F.A.)
| | - Hamid Saeed
- Departments of Pharmacy Practice (M.F.R., R.K., A.M.) and Pharmacology (I.I.), Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan; Section of Pharmaceutics, University College of Pharmacy, Allama Iqbal Campus, University of the Punjab, Lahore, Pakistan (H.S.); and Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia (F.F.A., M.M.A., F.A.)
| | - Fawaz Alasmari
- Departments of Pharmacy Practice (M.F.R., R.K., A.M.) and Pharmacology (I.I.), Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan; Section of Pharmaceutics, University College of Pharmacy, Allama Iqbal Campus, University of the Punjab, Lahore, Pakistan (H.S.); and Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia (F.F.A., M.M.A., F.A.)
| | - Mohammed Mufadhe Alanazi
- Departments of Pharmacy Practice (M.F.R., R.K., A.M.) and Pharmacology (I.I.), Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan; Section of Pharmaceutics, University College of Pharmacy, Allama Iqbal Campus, University of the Punjab, Lahore, Pakistan (H.S.); and Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia (F.F.A., M.M.A., F.A.)
| | - Faleh Alqahtani
- Departments of Pharmacy Practice (M.F.R., R.K., A.M.) and Pharmacology (I.I.), Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan; Section of Pharmaceutics, University College of Pharmacy, Allama Iqbal Campus, University of the Punjab, Lahore, Pakistan (H.S.); and Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia (F.F.A., M.M.A., F.A.)
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Yamazoe Y, Yoshinari K. Prediction of regioselectivity and preferred order of metabolisms on CYP1A2-mediated reactions part 3: Difference in substrate specificity of human and rodent CYP1A2 and the refinement of predicting system. Drug Metab Pharmacokinet 2019; 34:217-232. [DOI: 10.1016/j.dmpk.2019.02.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 12/04/2018] [Accepted: 02/01/2019] [Indexed: 12/11/2022]
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13
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Phe-125 and Phe-226 of pig cytochrome P450 1A2 stabilize the binding of aflatoxin B 1 and 7-ethoxyresorufin through the key CH/π interactions. Biochem Pharmacol 2019; 166:292-299. [PMID: 31173723 DOI: 10.1016/j.bcp.2019.05.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 05/31/2019] [Indexed: 11/22/2022]
Abstract
Cytochrome P450 1A2 (CYP1A2) plays important roles in the metabolism of many planar and aromatic drugs and also contributes to the bioactivation of aflatoxin B1 (AFB1) in vivo. To date, the structural basis for CYP1A2's preference to the planar substrates remains unclear. Herein, we investigated the structure-activity relationships for pig CYP1A2 catalyzing AFB1 and 7-ethoxyresorufin (7-ER). A molecular docking study was performed based on a constructed model of pig CYP1A2, which predicted the contributions of Thr-118, Thr-124, Phe-125, Phe-226, Leu-260, and Asp-313 to the substrate catalysis. Site-directed mutagenesis and kinetic analyses exhibited the common grounds: Phe-125, Phe-226 and Asp-313 were vital to AFB1 oxidation (including exo-epoxidation and 9A-hydroxylation) and ethoxyresorufin O-deethylation. Meanwhile, Phe-125 and Phe-226 formed CH/π interactions with AFB1/7-ER, and Asp-313 formed hydrogen bonds with them. Based on other published reports, this study further emphasizes the critical roles of Phe-125 and Phe-226 in recognizing the planar substrates. Our findings highlight the structural basis of pig CYP1A2 specifically catalyzing AFB1 and 7-ER, and may help to elucidate the underlying mechanism of CYP1A2's metabolic preference to the planar and aromatic substrates.
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Wu N, Feng Z, He X, Kwon W, Wang J, Xie XQ. Insight of Captagon Abuse by Chemogenomics Knowledgebase-guided Systems Pharmacology Target Mapping Analyses. Sci Rep 2019; 9:2268. [PMID: 30783122 PMCID: PMC6381188 DOI: 10.1038/s41598-018-35449-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 09/10/2018] [Indexed: 12/26/2022] Open
Abstract
Captagon, known by its genetic name Fenethylline, is an addictive drug that complicates the War on Drugs. Captagon has a strong CNS stimulating effect than its primary metabolite, Amphetamine. However, multi-targets issues associated with the drug and metabolites as well as its underlying mechanisms have not been fully defined. In the present work, we applied our established drug-abuse chemogenomics-knowledgebase systems pharmacology approach to conduct targets/off-targets mapping (SP-Targets) investigation of Captagon and its metabolites for hallucination addiction, and also analyzed the cell signaling pathways for both Amphetamine and Theophylline with data mining of available literature. Of note, Amphetamine, an agonist for trace amine-associated receptor 1 (TAAR1) with enhancing dopamine signaling (increase of irritability, aggression, etc.), is the main cause of Captagon addiction; Theophylline, an antagonist that blocks adenosine receptors (e.g. A2aR) in the brain responsible for restlessness and painlessness, may attenuate the behavioral sensitization caused by Amphetamine. We uncovered that Theophylline's metabolism and elimination could be retarded due to competition and/or blockage of the CYP2D6 enzyme by Amphetamine; We also found that the synergies between these two metabolites cause Captagon's psychoactive effects to act faster and far more potently than those of Amphetamine alone. We carried out further molecular docking modeling and molecular dynamics simulation to explore the molecular interactions between Amphetamine and Theophylline and their important GPCRs targets, including TAAR1 and adenosine receptors. All of the systems pharmacology analyses and results will shed light insight into a better understanding of Captagon addiction and future drug abuse prevention.
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Affiliation(s)
- Nan Wu
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- National Center of Excellence for Computational Drug Abuse Research, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
| | - Zhiwei Feng
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- National Center of Excellence for Computational Drug Abuse Research, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
| | - Xibing He
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- National Center of Excellence for Computational Drug Abuse Research, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
| | - William Kwon
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- National Center of Excellence for Computational Drug Abuse Research, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
- Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States
| | - Junmei Wang
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States.
- National Center of Excellence for Computational Drug Abuse Research, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States.
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States.
- Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States.
| | - Xiang-Qun Xie
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States.
- National Center of Excellence for Computational Drug Abuse Research, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States.
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States.
- Departments of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States.
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15
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Maideen NMP. Tobacco smoking and its drug interactions with comedications involving CYP and UGT enzymes and nicotine. World J Pharmacol 2019; 8:14-25. [DOI: 10.5497/wjp.v8.i2.14] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 01/20/2019] [Accepted: 01/28/2019] [Indexed: 02/06/2023] Open
Abstract
Tobacco smoking is a global public health threat causing several illnesses including cardiovascular disease (Myocardial infarction), cerebrovascular disease (Stroke), peripheral vascular disease (Claudication), chronic obstructive pulmonary disease, asthma, reduced female infertility, sexual dysfunction in men, different types of cancer and many other diseases. It has been estimated in 2015 that approximately 1.3 billion people smoke, around the globe. Use of medications among smokers is more common, nowadays. This review is aimed to identify the medications affected by smoking, involving Cytochrome P450 (CYP) and uridine diphosphate-glucuronosyltransferases (UGTs) enzymes and Nicotine. Polycyclic aromatic hydrocarbons (PAHs) of tobacco smoke have been associated with the induction of CYP enzymes such as CYP1A1, CYP1A2 and possibly CYP2E1 and UGT enzymes. The drugs metabolized by CYP1A1, CYP1A2, CYP2E1 and UGT enzymes might be affected by tobacco smoking and the smokers taking medications metabolized by those enzymes, may need higher doses due to decreased plasma concentrations through enhanced induction by PAHs of tobacco smoke. The prescribers and the pharmacists are required to be aware of medications affected by tobacco smoking to prevent the toxicity-associated complications during smoking cessation.
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16
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Food Bioactive Compounds and Their Interference in Drug Pharmacokinetic/Pharmacodynamic Profiles. Pharmaceutics 2018; 10:pharmaceutics10040277. [PMID: 30558213 PMCID: PMC6321138 DOI: 10.3390/pharmaceutics10040277] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 11/29/2018] [Accepted: 12/13/2018] [Indexed: 12/24/2022] Open
Abstract
Preclinical and clinical studies suggest that many food molecules could interact with drug transporters and metabolizing enzymes through different mechanisms, which are predictive of what would be observed clinically. Given the recent incorporation of dietary modifications or supplements in traditional medicine, an increase in potential food-drug interactions has also appeared. The objective of this article is to review data regarding the influence of food on drug efficacy. Data from Google Scholar, PubMed, and Scopus databases was reviewed for publications on pharmaceutical, pharmacokinetic, and pharmacodynamic mechanisms. The following online resources were used to integrate functional and bioinformatic results: FooDB, Phenol-Explorer, Dr. Duke's Phytochemical and Ethnobotanical Databases, DrugBank, UniProt, and IUPHAR/BPS Guide to Pharmacology. A wide range of food compounds were shown to interact with proteins involved in drug pharmacokinetic/pharmacodynamic profiles, starting from drug oral bioavailability to enteric/hepatic transport and metabolism, blood transport, and systemic transport/metabolism. Knowledge of any food components that may interfere with drug efficacy is essential, and would provide a link for obtaining a holistic view for cancer, cardiovascular, musculoskeletal, or neurological therapies. However, preclinical interaction may be irrelevant to clinical interaction, and health professionals should be aware of the limitations if they intend to optimize the therapeutic effects of drugs.
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17
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Rao F, Chen Z, Zhou D, Kang Y, Guo L, Xue Y. DFT investigation on the metabolic mechanisms of theophylline by cytochrome P450 monooxygenase. J Mol Graph Model 2018; 84:109-117. [PMID: 29957347 DOI: 10.1016/j.jmgm.2018.06.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 06/11/2018] [Accepted: 06/12/2018] [Indexed: 11/16/2022]
Abstract
Theophylline, one of the most commonly used bronchodilators and respiratory stimulators for the treatment of acute and chronic asthmatic conditions, can cause permanent neurological damage through chronic or excessive ingestion. In this work, DFT calculation was performed to identify the metabolic mechanisms of theophylline by cytochrome P450 (CYP450) monooxygenase. Two main metabolic pathways were investigated, namely, N1- (path A) and N3- (path B) demethylations, which proceeded through N-methyl hydroxylation followed by the decomposition of the generated carbinolamine species. N-methyl hydroxylation involved a hydrogen atom transfer (HAT) mechanism, which can be generalized as the N-demethylation mechanism of xanthine derivatives. The energy gap between the low-spin double state (LS) and the high-spin quartet state (HS) was low (<1 kcal mol-1), indicating a two-state reactivity (TSR) mechanism. The generated carbinolamine species preferred to decompose through the adjacent heteroatom (O6 for path A and O2 for path B) mediated mechanism. Path B was kinetically more feasible than path A attributed to its relatively lower activation energy. 1-Methylxanthine therefore was the energetically favorable metabolite of theophylline. The observations obtained in the work were in agreement with the experimental observation, which can offer important implications for further pharmacological and clinic studies.
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Affiliation(s)
- Fan Rao
- College of Chemistry and Chemical Engineering, Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China
| | - Zeqin Chen
- College of Chemistry and Chemical Engineering, Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China; College of Materials and Chemistry and Chemical Engineering, Chengdu University of Technology, Chengdu, 610059, China.
| | - Dagang Zhou
- College of Chemistry and Chemical Engineering, Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China.
| | - Yuan Kang
- College of Chemistry and Chemical Engineering, Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China
| | - Linfeng Guo
- College of Chemistry and Chemical Engineering, Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China
| | - Ying Xue
- College of Chemistry, Key Laboratory of Green Chemistry and Technology in Ministry of Education, Sichuan University, Chengdu, 610064, China
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18
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Henderson LM, Claw KG, Woodahl EL, Robinson RF, Boyer BB, Burke W, Thummel KE. P450 Pharmacogenetics in Indigenous North American Populations. J Pers Med 2018; 8:jpm8010009. [PMID: 29389890 PMCID: PMC5872083 DOI: 10.3390/jpm8010009] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 01/19/2018] [Accepted: 01/22/2018] [Indexed: 12/14/2022] Open
Abstract
Indigenous North American populations, including American Indian and Alaska Native peoples in the United States, the First Nations, Métis and Inuit peoples in Canada and Amerindians in Mexico, are historically under-represented in biomedical research, including genomic research on drug disposition and response. Without adequate representation in pharmacogenetic studies establishing genotype-phenotype relationships, Indigenous populations may not benefit fully from new innovations in precision medicine testing to tailor and improve the safety and efficacy of drug treatment, resulting in health care disparities. The purpose of this review is to summarize and evaluate what is currently known about cytochrome P450 genetic variation in Indigenous populations in North America and to highlight the importance of including these groups in future pharmacogenetic studies for implementation of personalized drug therapy.
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Affiliation(s)
- Lindsay M Henderson
- Departments of Pharmaceutics, University of Washington, Seattle, WA 98195, USA.
| | - Katrina G Claw
- Departments of Pharmaceutics, University of Washington, Seattle, WA 98195, USA.
| | - Erica L Woodahl
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, USA.
| | - Renee F Robinson
- Southcentral Foundation, Anchorage, AK 99508, USA.
- United States Public Health Service, Department of Human Services, Washington, DC 20201, USA.
| | - Bert B Boyer
- Center for Alaska Native Health Research, University of Alaska Fairbanks, Fairbanks, AK 99775, USA.
| | - Wylie Burke
- Bioethics & Humanities, University of Washington, Seattle, WA 98195, USA.
| | - Kenneth E Thummel
- Departments of Pharmaceutics, University of Washington, Seattle, WA 98195, USA.
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19
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Abstract
Optimizing the management of children presenting with acute severe asthma is of utmost importance to minimize hospital stays, morbidity, and mortality. Intravenous medications, including theophyllines, are used as second-line treatments for children experiencing a life-threatening exacerbation. For intravenous theophylline (aminophylline), guidelines and formularies recommend a target therapeutic range between 10 and 20 mg/l, with the commonest regimen being a loading dose of 5 mg/kg followed by an infusion calculated by age and weight. This review assesses the evidence underpinning these recommendations, highlighting the shortcomings in our understanding of the association between serum concentrations achieved, dose given, and clinical improvement experienced. To close the knowledge gap and improve outcomes for children presenting with acute severe asthma, we propose a series of research strategies to improve the assessment of illness severity, ascertain the optimal dose to maximize benefit and minimize risk, prospectively collect adverse events, and to better understand the inter-individual variation in responses to treatments.
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20
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Koonrungsesomboon N, Khatsri R, Wongchompoo P, Teekachunhatean S. The impact of genetic polymorphisms on CYP1A2 activity in humans: a systematic review and meta-analysis. THE PHARMACOGENOMICS JOURNAL 2017; 18:760-768. [DOI: 10.1038/s41397-017-0011-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 09/21/2017] [Accepted: 11/06/2017] [Indexed: 12/20/2022]
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21
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Kertys M, Urbanova A, Mokry J. Quantification of Theophylline in Guinea Pig Plasma by LC-MS/MS Using Hydrophilic Interaction Liquid Chromatography Stationary Phase: Method Development, Validation, and Application in Study. ACTA MEDICA MARTINIANA 2017. [DOI: 10.1515/acm-2017-0012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Theophylline has been used in the treatment of bronchial asthma and chronic obstructive pulmonary disease (COPD) for over 70 years. In order to maximize the effectiveness and safety of theophylline therapy it is important to individualize the dosage of the drug. In our study we focused on determination of theophylline concentrations in guinea pig plasma. A rapid, specific, and reliable LC-MS/MS-based method was developed and validated according to European Medicine Agency (EMA) guidelines. A hydrophilic interaction liquid chromatography (HILIC) separation mode for reduction time of sample preparation was used. The analysed sample was quantified in a positive ionization mode. Multiple reaction monitoring (MRM) using transition m/z 181.06→124.06 and m/z 187.17→127.06 was performed to quantify theophylline with deuterated internal standard ([2H6]-theophylline), respectively. Modification of collision energies was performed in parallel with chromatographic separation to further eliminate interference from the matrix. The method was validated for a range of 0.5 to 30 μg/mL of plasma sample. The intra-day and inter-day precision and accuracy of the quality control samples at low, me dium, and high concentration levels exhibited relative standard deviations (RSD) of less than 10 %. The method was successfully applied for the quantitation of theophylline in guinea pig plasma for better understanding its effects in a model of ovalbumin-induced allergic inflammation.
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Affiliation(s)
- M Kertys
- Department of Pharmacology, Jessenius Faculty of Medicine in Martin , Comenius University in Bratislava , Slovakia
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin , Comenius University in Bratislava , Slovakia
| | - A Urbanova
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin , Comenius University in Bratislava , Slovakia
- Department of Pharmacology, Jessenius Faculty of Medicine in Martin , Comenius University in Bratislava , Slovakia
| | - J Mokry
- Department of Pharmacology, Jessenius Faculty of Medicine in Martin , Comenius University in Bratislava , Slovakia
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin , Comenius University in Bratislava , Slovakia
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22
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Lu Y, Zhong H, Tang Q, Huang Z, Jing N, Smith J, Miao R, Li Y, Yuan H. Construction and verification of CYP3A5 gene polymorphisms using a Saccharomyces cerevisiae expression system to predict drug metabolism. Mol Med Rep 2017; 15:1593-1600. [PMID: 28259948 PMCID: PMC5364972 DOI: 10.3892/mmr.2017.6214] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 01/05/2017] [Indexed: 11/25/2022] Open
Abstract
The present study evaluated the ability of a Saccharomyces cerevisiae expression system to predict the pharmacokinetic (PK) activity of a calcium channel blocker in patients with distinct cytochrome P450 3A5 (CYP3A5) polymorphisms. The blood pressure lowering activity of amlodipine in 57 hypertensive patients with CYP3A5*1/*1, CYP3A5*1/*3, CYP3A5*4 and CYP3A5*6 polymorphisms was evaluated by the current study. Subsequently, a Saccharomyces cerevisiae expression system for CYP3A5 gene polymorphisms was constructed to examine the PK activity of CYP3A5*1/*1, CYP3A5*4 and CYP3A5*6 polymorphisms. This system was used to predict the PK of amlodipine and was compared with the in vivo data from different gene polymorphism groups. The blood pressure lowering activity of amlodipine in hypertensive patients varied among CYP3A5 polymorphisms. The in vivo results demonstrated that CYP3A5*6 exhibited the highest metabolic rate, followed by CYP3A5*1/*1, CYP3A5*4 and CYP3A5*1/*3. The difference between CYP3A5*6 and CYP3A5*1/*1 was not statistically significant (P=0.5). In accordance with in vivo data, CYP3A5*1/*1 exhibited the highest in vitro metabolic rate, followed by CYP3A5*6 and CYP3A5*4. With the exception of the comparison between CYP3A5*6 and CYP3A5*1/*1, polymorphisms exhibited statistically significant differences compared with CYP3A5*1/*1 (P<0.05). The Saccharomyces cerevisiae expression system may be a cost effective and potentially useful tool for assessing the PK activity of drugs that are metabolized by CYP3A5.
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Affiliation(s)
- Yao Lu
- Department of Clinical Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Hua Zhong
- Department of Cardiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Qing Tang
- Department of Cardiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Zhijun Huang
- Department of Clinical Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Ningning Jing
- Department of Cardiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Julie Smith
- School of Community Health Sciences, University of Nevada, Reno, NV 89557, USA
| | - Rujia Miao
- Department of Clinical Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Yapei Li
- Department of Clinical Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Hong Yuan
- Department of Clinical Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
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23
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Zhang Z, Unadkat JD. Development of a Novel Maternal-Fetal Physiologically Based Pharmacokinetic Model II: Verification of the model for passive placental permeability drugs. Drug Metab Dispos 2017; 45:939-946. [PMID: 28049636 DOI: 10.1124/dmd.116.073957] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 12/29/2016] [Indexed: 01/01/2023] Open
Abstract
Fetal exposure to drugs cannot be readily estimated from single time point cord blood sampling at the time of delivery. Therefore, we developed a physiologically based pharmacokinetic (PBPK) model to estimate fetal drug exposure throughout pregnancy. In this study, we report verification of this novel maternal-fetal PBPK (m-f-PBPK) model for drugs that passively diffuse across the placenta and are not metabolized/transported there. Our recently built m-f-PBPK model was populated with gestational age-dependent changes in maternal drug disposition and maternal-fetal physiology. Using midazolam as an in vivo calibrator, the transplacental passive diffusion clearance of theophylline and zidovudine was first estimated. Then, for verification, the predicted maternal plasma (MP) and umbilical venous (UV) plasma drug concentrations by our m-f-PBPK were compared against those observed at term. Overall, our m-f-PBPK model well predicted the maternal and fetal exposure to the two verification drugs, theophylline and zidovudine, at term, across a range of dosing regimens, with nearly all observed MP and UV plasma drug concentrations falling within the 90% prediction interval [i.e., 5th-95th percentile range of a virtual pregnant population (n = 100)]. Prediction precision and bias of theophylline MP and UV were 14.5% and 12.4%, and 9.4% and 7.5%, respectively. Furthermore, for zidovudine, after the exclusion of one unexpectedly low MP concentration, prediction precision and bias for MP and UV were 50.3% and 30.2, and 28.3% and 15.0%, respectively. This m-f-PBPK should be useful to predict fetal exposure to drugs, throughout pregnancy, for drugs that passively diffuse across the placenta.
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Affiliation(s)
- Zufei Zhang
- Department of Pharmaceutics, University of Washington, Seattle, Washington
| | - Jashvant D Unadkat
- Department of Pharmaceutics, University of Washington, Seattle, Washington
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24
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Rao PSS, Midde NM, Miller DD, Chauhan S, Kumar A, Kumar S. Diallyl Sulfide: Potential Use in Novel Therapeutic Interventions in Alcohol, Drugs, and Disease Mediated Cellular Toxicity by Targeting Cytochrome P450 2E1. Curr Drug Metab 2016; 16:486-503. [PMID: 26264202 DOI: 10.2174/1389200216666150812123554] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 08/05/2015] [Indexed: 12/16/2022]
Abstract
Diallyl sulfide (DAS) and other organosulfur compounds are chief constituents of garlic. These compounds have many health benefits, as they are very efficient in detoxifying natural agents. Therefore, these compounds may be useful for prevention/treatment of cancers. However, DAS has shown appreciable allergic reactions and toxicity, as they can also affect normal cells. Thus their use as in the prevention and treatment of cancer is limited. DAS is a selective inhibitor of cytochrome P450 2E1 (CYP2E1), which is known to metabolize many xenobiotics including alcohol and analgesic drugs in the liver. CYP2E1-mediated alcohol/drug metabolism produce reactive oxygen species and reactive metabolites, which damage DNA, protein, and lipid membranes, subsequently causing liver damage. Several groups have shown that DAS is not only capable of inhibiting alcohol- and drug-mediated cellular toxicities, but also HIV protein- and diabetes-mediated toxicities by selectively inhibiting CYP2E1 in various cell types. However, due to known DAS toxicities, its use as a treatment modality for alcohol/drug- and HIV/diabetes-mediated toxicity have only limited clinical relevance. Therefore, effort is being made to generate DAS analogs, which are potent and selective inhibitor of CYP2E1 and poor substrate of CYP2E1. This review summarizes current advances in the field of DAS, its anticancer properties, role as a CYP2E1 inhibitor, preventing agent of cellular toxicities from alcohol, analgesic drugs, xenobiotics, as well as, from diseases like HIV and diabetes. Finally, this review also provides insights toward developing novel DAS analogues for chemical intervention of many disease conditions by targeting CYP2E1 enzyme.
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Affiliation(s)
| | | | | | | | | | - Santosh Kumar
- College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Ave, Rm 456, Memphis, TN 38163, USA.
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25
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Yu T, Campbell SC, Stockmann C, Tak C, Schoen K, Clark EAS, Varner MW, Spigarelli MG, Sherwin CMT. Pregnancy-induced changes in the pharmacokinetics of caffeine and its metabolites. J Clin Pharmacol 2015; 56:590-6. [PMID: 26358647 DOI: 10.1002/jcph.632] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/08/2015] [Indexed: 01/18/2023]
Abstract
This study sought to assess the pharmacokinetic (PK) changes of caffeine and its CYP1A2 metabolites across the 3 trimesters of pregnancy. A prospective, multicenter PK study was conducted among 59 pregnant women (93.2% white) who were studied once during a trimester. One beverage with 30-95 mg caffeine was consumed, and a blood/urine sample was collected within 1 hour postingestion. Concentrations of caffeine and its primary metabolites were quantified from serum and urine by LC-MS/MS. There was a significant increase in dose-normalized caffeine serum and urine concentrations between the first and third trimesters (P < .05 and P < .01, respectively). Normalized theophylline concentrations also increased significantly in the third trimester in serum (P < .001) and in urine (P < .05). The caffeine urine/serum concentration ratio also increased in the last trimester (P < .05). No significant difference was found in normalized paraxanthine or theobromine concentrations. This study identified decreased caffeine metabolism and an increase in the active metabolite theophylline concentrations during pregnancy, especially in the third trimester, revealing evidence of the large role that pregnancy plays in influencing caffeine metabolism.
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Affiliation(s)
- Tian Yu
- Division of Clinical Pharmacology, School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Sarah C Campbell
- Division of Clinical Pharmacology, School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Chris Stockmann
- Division of Clinical Pharmacology, School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Casey Tak
- Clinical Trials Office, Department of Pediatrics, School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Katherine Schoen
- Division of Clinical Pharmacology, School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Erin A S Clark
- Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Michael W Varner
- Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, School of Medicine, University of Utah, Salt Lake City, UT, USA.,Intermountain Healthcare, Women and Newborns Clinical Programs, Salt Lake City, Utah, USA
| | - Michael G Spigarelli
- Division of Clinical Pharmacology, School of Medicine, University of Utah, Salt Lake City, UT, USA.,Clinical Trials Office, Department of Pediatrics, School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Catherine M T Sherwin
- Division of Clinical Pharmacology, School of Medicine, University of Utah, Salt Lake City, UT, USA.,Clinical Trials Office, Department of Pediatrics, School of Medicine, University of Utah, Salt Lake City, UT, USA
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Al-Mohizea AM, Raish M, Ahad A, Al-Jenoobi FI, Alam MA. Pharmacokinetic interaction of Acacia catechu with CYP1A substrate theophylline in rabbits. J TRADIT CHIN MED 2015; 35:588-93. [PMID: 26591691 DOI: 10.1016/s0254-6272(15)30144-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To investigate the effect of black catechu (BC) on the pharmacokinetics of theophylline (CYP1A2 substrate, with narrow therapeutic index) in rabbits. METHODS In the present investigation the effect of BC on the pharmacokinetics of theophylline, a CYP1A2 substrate was determined. In the study, BC (264 mg/kg, p. o.) or saline (control group) was given to rabbits for 7 consecutive days and on the 8th day theophylline (16 mg/kg) was administered orally one hour after BC or saline treatment. Blood samples were withdrawn at different time intervals (0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24 and 36 h) from the marginal ear vein. RESULTS The pretreatment of rabbits with BC resulted in a significant increase in maximum blood concentration, time of peak concentration and area under the concentration time profile curve until last observation which was about 41.32%, 35.71% and 15.03%, respectively. While decreases in clearance, volume of distribution, and half-life were observed. It is suggested that BC pretreatment decreases the CYP1A metabolic activity leading to increase in bioavailability and decrease in oral clearance of theophylline, which may be due to inhibition of CYP1A. CONCLUSION BC can significantly alter theophylline pharmacokinetics in vivo possibly due to inhibition of CYP1A and P-glycoprotein activity. Based on these results, precaution should be exercised when administering BC with CYP1A substrate.
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Tang J, Ji H, Shi J, Wu L. Ephedra water decoction and cough tablets containing ephedra and liquorice induce CYP1A2 but not CYP2E1 hepatic enzymes in rats. Xenobiotica 2015; 46:141-6. [PMID: 26153439 DOI: 10.3109/00498254.2015.1060371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
1. Ephedra water decoction (EWD) and cough tablets containing ephedra and liquorice (maxing cough tablets, MXCT) have been widely used in the treatment of asthma. In the clinic, EWD and MXCT may be prescribed with theophylline, one of the most popular antiasthmatic drugs. CYP1A2 and CYP2E1 are mainly involved in the oxidative metabolism of theophylline in human liver. Drug interactions involving the cytochrome P450 (CYP) isoforms generally are of two types: enzyme induction or enzyme inhibition. Enzyme inhibition reduces metabolism, whereas induction can increase it. 2. To evaluate the pretreatment effect of EWD and MXCT on CYP1A2 and CYP2E1, CYP1A2 and CYP2E1 activity, the protein expression and mRNA expression levels were determined. After pretreatment with EWD or MXCT, the enzyme activity, mRNA expression and protein expression of CYP1A2 were increased significantly (p < 0.05), but enzyme activity of CYP2E1 did not change compared with the control. 3. It was demonstrated that EWD or MXCT pretreatment obviously induced CYP1A2, therefore, in patients taking EWD or MXCT, possible CYP-induced drug interaction should be noted to decrease the risk of therapeutic failure or adverse effects resulting from the use of additional therapeutic agents.
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Affiliation(s)
- Jingling Tang
- a Department of Pharmaceutics , School of Pharmacy, Harbin Medical University , Harbin , P.R. China
| | - Hongyu Ji
- b Department of Pharmacy , The Second Affiliated Hospital, College of Heilongjiang Province, Harbin Medical University, Key Laboratory of Medications Research , Harbin , P.R. China , and
| | - Jing Shi
- a Department of Pharmaceutics , School of Pharmacy, Harbin Medical University , Harbin , P.R. China .,c Hulun Buir Institute for Food and Drug Control , Hulun Buir , P.R. China
| | - Linhua Wu
- a Department of Pharmaceutics , School of Pharmacy, Harbin Medical University , Harbin , P.R. China .,b Department of Pharmacy , The Second Affiliated Hospital, College of Heilongjiang Province, Harbin Medical University, Key Laboratory of Medications Research , Harbin , P.R. China , and
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Abstract
Apnea of prematurity (AOP) is a common complication of preterm birth, which affects more than 80 % of neonates with a birth weight less than 1,000 g. Methylxanthine therapies, including caffeine and theophylline, are a mainstay in the treatment and prevention of AOP. Despite their frequent use, little is known about the long-term safety and efficacy of these medications. In this review, we systematically evaluated the literature on neonatal methylxanthine therapies and found that caffeine is associated with fewer adverse effects and a wider therapeutic window when compared with theophylline. When used as a therapeutic agent, larger doses of caffeine citrate have been shown to improve acute neonatal outcomes when administered promptly, although further studies are needed to assess the long-term neurological consequences associated with the use of large loading doses. In a secondary analysis of data obtained from a randomized controlled trial, the prophylactic use of caffeine was associated with substantial cost savings and improved clinical outcomes. However, there remains a paucity of well-controlled, randomized clinical trials that have examined the use of caffeine as a prophylactic agent, and further prospective trials are needed to determine if caffeine is a safe and effective prophylactic agent. Additionally, measuring plasma concentrations longitudinally as a marker of therapeutic efficacy and/or toxicity has not been shown to be clinically useful in neonates who are responsive to treatment and exhibit no signs or symptoms of toxicity. However, in cases where toxicity is of concern or for neonates with congenital or pathophysiologic process that may alter the pharmacokinetics of these drugs, therapeutic drug monitoring may be warranted to monitor for methylxanthine toxicity.
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Salem F, Johnson TN, Abduljalil K, Tucker GT, Rostami-Hodjegan A. A Re-evaluation and Validation of Ontogeny Functions for Cytochrome P450 1A2 and 3A4 Based on In Vivo Data. Clin Pharmacokinet 2014; 53:625-36. [DOI: 10.1007/s40262-014-0140-7] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Nikolic VN, Jankovic SM, Velickovic-Radovanovlć R, Apostolovlć S, Stanojevic D, Zivanovic S, Stefanovic N, Pesic S, Jevtovic-Stoimenov T, Djuric J, Markovic V, Milovanovic JR. Population Pharmacokinetics of Carvedilol in Patients with Congestive Heart Failure. J Pharm Sci 2013; 102:2851-8. [DOI: 10.1002/jps.23626] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2013] [Revised: 05/07/2013] [Accepted: 05/08/2013] [Indexed: 11/08/2022]
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Perera V, Gross AS, Polasek TM, Qin Y, Rao G, Forrest A, Xu J, McLachlan AJ. Considering CYP1A2 phenotype and genotype for optimizing the dose of olanzapine in the management of schizophrenia. Expert Opin Drug Metab Toxicol 2013; 9:1115-37. [PMID: 23641727 DOI: 10.1517/17425255.2013.795540] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Schizophrenia, a mental disorder, is a debilitating condition which typically strikes young people in their early 20's. Antipsychotic medications are widely prescribed for the treatment of schizophrenia however a balancing act is necessary to provide the correct dose to each patient. It is suggested that a large number of patients discontinue antipsychotic pharmacotherapy because the treatments provided do not always reduce the positive symptoms of the disease, while many have adverse effects on the patients. This implies that neither the incorrect drug nor the optimal dosage for that patient is achieved. AREAS COVERED The current review investigates variability in response to olanzapine with a specific focus on the common intrinsic and extrinsic factors that influence both olanzapine and CYP1A2 activity. Furthermore, the authors discuss the utilization of phenotyping and genotyping of CYP1A2 and their potential utility in clinical practice for olanzapine dosing regimens. The authors also consider the potential of pharmacometrics compared to pharmacogenomics as a tool to personalize medicine. EXPERT OPINION Careful consideration must be given to the impact of a genetic variant on the disposition of a drug prior to implementing genetic 'tests' to determine response. CYP1A2 phenotypic assessment can yield important information regarding the disposition of olanzapine; however, it relies on the accuracy of the metric and the minimal impact of other metabolic pathways. The application of pharmacometrics provides an effective method to establish covariates that significantly influence olanzapine disposition which can incorporate phenotype and/or genotype.
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Affiliation(s)
- Vidya Perera
- University at Buffalo, The State University of New York, School of Pharmacy and Pharmaceutical Sciences, Buffalo, NY, USA.
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Chae JW, Baek IH, Kwon KI. Effect of decursin on the pharmacokinetics of theophylline and its metabolites in rats. JOURNAL OF ETHNOPHARMACOLOGY 2012; 144:248-254. [PMID: 22981724 DOI: 10.1016/j.jep.2012.08.046] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 07/17/2012] [Accepted: 08/25/2012] [Indexed: 06/01/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Decursin is used as a traditional Asian medicine to treat various women's diseases. AIM OF THE STUDY Herb-drug interaction has become a serious problem since herbal medicine is extensively used in the modern world. This study investigates effects of decursin, on the pharmacokinetics of theophylline, a typical substrate of cytochrome P450 1A2 enzyme, in rats. MATERIALS AND METHODS After decursin pretreatment for 3 days, on the fourth day rats were administered decursin and theophylline concomitantly. The blood theophylline and its major metabolites (1-methylxanthine (1-MX), 3-methylxanthine (3-MX), 1-methyluric acid (1-MU), and 1,3-dimethyluric acid (1,3-DMU)) levels were monitored with LC-MS/MS. RESULTS The results indicated that the clearance, elimination rate constant (K(el)) of theophylline was significantly decreased and area under concentration-time curve (AUC), C(max), half-life was increased in decursin (25mg/kg) pretreatment when theophylline (10mg/kg) was given. In the presence of decursin, the pharmacokinetic parameters of three metabolites (1-MX, 1,3-DMU, and 1-MU) were affected and the differences were statistically significant about AUC(24)(h) parameter. CONCLUSION Our results suggest that patients who want to use CYP1A2-metabolized drugs such as caffeine and theophylline should be advised of the potential herb-drug interaction, to reduce therapeutic failure or increased toxicity of conventional drug therapy.
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Affiliation(s)
- Jung-woo Chae
- College of Pharmacy, Chungnam National University, Daejeon, Korea
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Chae JW, An JH, Kang W, Ma JY, Kwon KI. Effect of decursinol angelate on the pharmacokinetics of theophylline and its metabolites in rats. Food Chem Toxicol 2012; 50:3666-72. [DOI: 10.1016/j.fct.2012.06.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 05/31/2012] [Accepted: 06/27/2012] [Indexed: 10/28/2022]
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Erkekoglu P, Giray BK, Caglayan A, Hincal F. Selenium and/or iodine deficiency alters hepatic xenobiotic metabolizing enzyme activities in rats. J Trace Elem Med Biol 2012; 26:36-41. [PMID: 22366236 DOI: 10.1016/j.jtemb.2011.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 10/10/2011] [Accepted: 12/11/2011] [Indexed: 01/12/2023]
Abstract
The objective of this study was to investigate the effects of iodine (I(2)) and/or selenium (Se) deficiency on thyroid hormones and hepatic xenobiotic metabolizing enzyme systems using a triple animal model. Three-week-old male Wistar rats were fed for seven weeks. Se deficiency was introduced by a diet containing <0.005 mg/kg Se, and I(2) deficiency was produced by sodium perchlorate containing drinking water. The levels of plasma thyroid hormones [total T(4) (TT(4)), total T(3) (TT(3))], thyroid stimulating hormone (TSH); total microsomal cytochrome P450 (CYP450) and cytochrome b5 (CYP b5) levels; activities of microsomal NADPH-cytochrome P450 reductase (P450R), microsomal aniline hydroxylase (CYP2E1), microsomal 7-ethoxyresorufin O-deethylase (EROD), microsomal 7-pentoxyresorufin O-depentylase (PROD) and cytosolic glutathione S-transferase (GST) were determined. In I(2) deficiency total CYP450 levels, activities of CYP2E1, EROD and GST decreased, and CYP b5 content increased significantly. In Se-deficient rats, total CYP450 level and CYP2E1 activity increased, and EROD and GST activities and CYP b5 level decreased significantly. In combined I(2) and Se deficiency, except for CYP450 content and CYP2E1 activity, all enzyme activities and CYP b5 content decreased significantly compared to control group. Overall results of this study have suggested that metabolism of xenobiotics as well as endogenous compounds is affected by Se and I(2) status.
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Affiliation(s)
- Pinar Erkekoglu
- Hacettepe University, Faculty of Pharmacy, Department of Toxicology, Ankara 06100, Turkey
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35
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Gaïes E, Trabelsi S, Salouage I, Jebabli N, Charfi R, Lakhal M, Klouz A. [Interaction between tacrolimus and theophylline in a renal transplant recipient: a case report]. Therapie 2011; 66:553-4. [PMID: 22186080 DOI: 10.2515/therapie/2011064] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Accepted: 07/06/2011] [Indexed: 12/27/2022]
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Modulation of pharmacokinetics of theophylline by antofloxacin, a novel 8-amino-fluoroquinolone, in humans. Acta Pharmacol Sin 2011; 32:1285-93. [PMID: 21892200 DOI: 10.1038/aps.2011.78] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
AIM To evaluate the pharmacokinetic interactions between theophylline and antofloxacin in vivo and in vitro. METHODS A randomized, 5-day treatment and 3-way crossover design was documented in 12 healthy subjects. The subjects were orally administered with antofloxacin (400 mg on d 1 and 200 mg on d 2 to 5), theophylline (100 mg twice a day and morning dose 200 mg on d 1 and 5), or theophylline plus antofloxacin. The plasma and urinary pharmacokinetics of antofloxacin and theophylline were characterized after the first and last dose. The effect of antofloxacin on theophylline metabolism was also investigated in pooled human liver microsomes. RESULTS The 5-day treatment with antofloxacin significantly increased the area of the plasma concentration-time curve and peak plasma concentration of theophylline, accompanied by a decrease in the excretion of theophylline metabolites. On the contrary, theophylline did not affect the pharmacokinetics of antofloxacin. In vitro studies using pooled human hepatic microsomes demonstrated that antofloxacin was a weak reversible and mechanism-based inhibitor of CYP1A2. The clinical interaction between theophylline and antofloxacin was further validated by the in vitro results. CONCLUSION The results showed that antofloxacin increases the plasma theophylline concentration, partly by acting as a mechanism-based inhibitor of CYP1A2.
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de Wildt SN. Profound changes in drug metabolism enzymes and possible effects on drug therapy in neonates and children. Expert Opin Drug Metab Toxicol 2011; 7:935-48. [PMID: 21548840 DOI: 10.1517/17425255.2011.577739] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION There are profound changes that take place in drug metabolism enzymes during fetal and postnatal development. These changes may significantly impact drug therapy in children. AREAS COVERED A combination of focused and comprehensive literature searches using PubMed and reference lists (from inception to 7 November 2009) is undertaken to identify reports on in vitro and in vivo development of drug metabolism enzymes as well disposition of selected drugs and their effect in children. The article provides an update on development of drug metabolism enzymes and their impact on drug substrate disposition and disease, which may aid to improve clinical practice and optimally design clinical trials in children. EXPERT OPINION Drug metabolism enzyme activity changes profoundly throughout the continuum of postnatal development and often results in different disposition pathways than in adults. Genetics and co-morbidity interact significantly with these developmental changes. Translation of existing knowledge into age-adjusted dosing guidelines and clinical trial design is highly needed for there to be an improvement in drug therapy in children.
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Affiliation(s)
- Saskia N de Wildt
- Erasmus MC Sophia Children's Hospital, Pediatric Surgery & Intensive Care, GJ Rotterdam, The Netherlands.
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Chen C, Han YH, Yang Z, Rodrigues AD. Effect of interferon-α2b on the expression of various drug-metabolizing enzymes and transporters in co-cultures of freshly prepared human primary hepatocytes. Xenobiotica 2011; 41:476-85. [PMID: 21381897 DOI: 10.3109/00498254.2011.560971] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The purpose of this study was to assess the impact of interferon-α2b (IFN-α2b) on the expression of various drug-metabolizing enzymes and transporters in freshly prepared co-cultures (parenchymal and non-parenchymal cells) of human primary hepatocytes. At therapeutically relevant concentrations (from 1000 to 3000 IU/mL), IFN-α2b up-regulated STAT1 (signal transducer and activator of transcription factor 1) mRNA expression. Conversely, three cytochrome P450s (CYP1A2, CYP2B6, CYP2E1), a UDP-glucuronosyltransferase (UGT2B7), a sulphotransferase (SULT1A1) and organic anion transporter (OAT2) were significantly down-regulated (~50%; P < 0.05). Western blot analysis of CYP1A2, UGT2B7 and OAT2 protein supported the mRNA data. Two peroxisome proliferator activator receptor alpha (PPARα)-controlled genes (pyruvate dehydrogenase kinase 4 and adipose differentiation-related protein), CYP3A4 and multidrug resistance-associated protein 2 were significantly up-regulated (up to 223%; P < 0.05). On the other hand, SULT2A1, carboxylesterase 2, organic anion transporting peptide (OATP1B1, OATP1B3, OATP2B1), organic cation transporter 1, P-glycoprotein and breast cancer resistance protein mRNA expression was not significantly affected. Western blot analysis of CYP3A4 supported the mRNA data also. The present results demonstrated complex interactions between IFN-α2b and hepatocytes and the observed down-regulation of CYP1A2, OAT2 and UGT2B7 is consistent with reports of drug interactions between IFN-α2b and drugs such as theophylline, clozapine and gemfibrozil.
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Affiliation(s)
- Cliff Chen
- Metabolism and Pharmacokinetics, Pharmaceutical Candidate Optimization, Bristol-Myers Squibb, Princeton, NJ 08543, USA.
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Antoniou T, Gomes T, Mamdani MM, Juurlink DN. Ciprofloxacin-induced theophylline toxicity: a population-based study. Eur J Clin Pharmacol 2011; 67:521-6. [PMID: 21234553 DOI: 10.1007/s00228-010-0985-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 12/22/2010] [Indexed: 10/18/2022]
Abstract
PURPOSE Ciprofloxacin can inhibit the cytochrome P450-mediated metabolism of theophylline, but the clinical relevance of this drug interaction is uncertain. We studied the risk of theophylline toxicity associated with the co-prescription of ciprofloxacin and theophylline. METHODS This was a population-based, nested case-control study of a cohort of Ontario residents aged 66 years of age or older treated with theophylline between April 1, 1992 and March 31, 2009. Within this group, case patients were those hospitalized with theophylline toxicity. For each case, 50 age- and sex-matched control patients were identified from the same cohort. The odds ratio (OR) for the association between hospitalization for theophylline toxicity and receipt of ciprofloxacin in the 14 days preceding hospitalization was determined. RESULTS Among the 77,251 elderly patients receiving therapy with theophylline, 180 eligible case patients hospitalized for theophylline toxicity and 9000 matched controls were identified. Following multivariable adjustment, a nearly twofold increase in the risk of theophylline toxicity following the receipt of ciprofloxacin was observed [adjusted OR 1.86, 95% confidence interval (CI) 1.18-2.93]. In contrast, there was no increased risk of theophylline toxicity within a group of patients receiving neutral comparator antibiotics (levofloxacin, trimethoprim-sulfamethoxazole or cefuroxime) (adjusted OR 0.78; 95% CI 0.38-1.62). CONCLUSION Treatment with ciprofloxacin is associated with a significant increase in the risk of theophylline toxicity. When clinically appropriate, alternate antibiotics should be considered for elderly patients receiving theophylline.
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Suzuki T, Yamamoto H, Pfleiderer W. Nitrosation of N-methyl derivatives of uric acid and their transnitrosation ability to N-acetylcysteine. Chem Pharm Bull (Tokyo) 2011; 58:1271-5. [PMID: 20823616 DOI: 10.1248/cpb.58.1271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
When 1,3-dimethyluric acid was treated with a nitric oxide donor, diethylamine NONOate, in an aerobic neutral solution and the reaction was analyzed by HPLC, 1,3-dimethyluric acid was consumed to yield a nitrosated derivative, which decomposed with a half-life of 17.9 min at pH 7.4 and 37 degrees C. When 1,3,7-trimethyluric acid was treated with diethylamine NONOate, no consumption of 1,3,7-trimethyluric acid was observed. However, in the reaction of N-acetylcysteine with diethylamine NONOate, the yield of N-acetyl-S-nitrosocysteine increased by the addition of 1,3,7-trimethyluric acid as well as 1,3-dimethyluric acid. For 1,3,7,9-tetramethyluric acid, no consumption in the reaction with diethylamine NONOate and no effect on the S-nitrosation were observed. These results suggest that 1,3-dimethyluric and 1,3,7-trimethyluric acids are both nitrosated by diethylamine NONOate on the nitrogen atom of their oxoimidazole ring, although the half-life of the nitrosated 1,3,7-trimethyluric acid is too short to detect by HPLC. Consequently, these two acids can act as vehicles of nitric oxide.
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Affiliation(s)
- Toshinori Suzuki
- School of Pharmacy, Shujitsu University, Okayama 703-8516, Japan.
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Abstract
Caffeine, theophylline, theobromine, and paraxanthine administered to animals and humans distribute in all body fluids and cross all biological membranes. They do not accumulate in organs or tissues and are extensively metabolized by the liver, with less than 2% of caffeine administered excreted unchanged in human urine. Dose-independent and dose-dependent pharmacokinetics of caffeine and other dimethylxanthines may be observed and explained by saturation of metabolic pathways and impaired elimination due to the immaturity of hepatic enzyme and liver diseases. While gender and menstrual cycle have little effect on their elimination, decreased clearance is seen in women using oral contraceptives and during pregnancy. Obesity, physical exercise, diseases, and particularly smoking and the interactions of drugs affect their elimination owing to either stimulation or inhibition of CYP1A2. Their metabolic pathways exhibit important quantitative and qualitative differences in animal species and man. Chronic ingestion or restriction of caffeine intake in man has a small effect on their disposition, but dietary constituents, including broccoli and herbal tea, as well as alcohol were shown to modify their plasma pharmacokinetics. Using molar ratios of metabolites in plasma and/or urine, phenotyping of various enzyme activities, such as cytochrome monooxygenases, N-acetylation, 8-hydroxylation, and xanthine oxidase, has become a valuable tool to identify polymorphisms and to understand individual variations and potential associations with health risks in epidemiological surveys.
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Affiliation(s)
- Maurice J Arnaud
- Nutrition and Biochemistry, Bourg-Dessous 2A, La Tour-de-Peilz, Switzerland.
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Klein K, Winter S, Turpeinen M, Schwab M, Zanger UM. Pathway-Targeted Pharmacogenomics of CYP1A2 in Human Liver. Front Pharmacol 2010; 1:129. [PMID: 21918647 PMCID: PMC3171976 DOI: 10.3389/fphar.2010.00129] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 09/28/2010] [Indexed: 01/08/2023] Open
Abstract
The human drug metabolizing cytochrome P450 (CYP) 1A2, is one of the major P450 isoforms contributing by about 5–20% to the hepatic P450 pool and catalyzing oxidative biotransformation of up to 10% of clinically relevant drugs including clozapine and caffeine. CYP1A2 activity is interindividually highly variable and although twin studies have suggested a high heritability, underlying genetic factors are still unknown. Here we adopted a pathway-oriented approach using a large human liver bank (n = 150) to elucidate whether variants in candidate genes of constitutive, ligand-inducible, and pathophysiological inhibitory regulatory pathways may explain different hepatic CYP1A2 phenotypes. Samples were phenotyped for phenacetin O-deethylase activity, and the expression of CYP1A2 protein and mRNA was determined. CYP1A2 expression and function was increased in smokers and decreased in patients with inflammation and cholestasis. Of 169 SNPs in 17 candidate genes including the CYP1A locus, 136 non-redundant SNPs with minor allele frequency >5% were analyzed by univariate and multivariate methods. A total of 13 strong significant associations were identified, of which 10 SNPs in the ARNT, AhRR, HNF1α, IL1β, SRC-1, and VDR genes showed consistent changes for at least two phenotypes by univariate analysis. Multivariate linear modeling indicated that the polymorphisms and non-genetic factors together explained 42, 38, and 33% of CYP1A2 variation at activity, protein and mRNA levels, respectively. In conclusion, we identified novel trans-associations between regulatory genes and hepatic CYP1A2 function and expression, but additional genetic factors must be assumed to explain the full extent of CYP1A2 heritability.
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Affiliation(s)
- Kathrin Klein
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, University of Tuebingen Stuttgart, Germany
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Zhou SF, Wang B, Yang LP, Liu JP. Structure, function, regulation and polymorphism and the clinical significance of human cytochrome P450 1A2. Drug Metab Rev 2010; 42:268-354. [PMID: 19961320 DOI: 10.3109/03602530903286476] [Citation(s) in RCA: 183] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Human CYP1A2 is one of the major CYPs in human liver and metabolizes a number of clinical drugs (e.g., clozapine, tacrine, tizanidine, and theophylline; n > 110), a number of procarcinogens (e.g., benzo[a]pyrene and aromatic amines), and several important endogenous compounds (e.g., steroids). CYP1A2 is subject to reversible and/or irreversible inhibition by a number of drugs, natural substances, and other compounds. The CYP1A gene cluster has been mapped on to chromosome 15q24.1, with close link between CYP1A1 and 1A2 sharing a common 5'-flanking region. The human CYP1A2 gene spans almost 7.8 kb comprising seven exons and six introns and codes a 515-residue protein with a molecular mass of 58,294 Da. The recently resolved CYP1A2 structure has a relatively compact, planar active site cavity that is highly adapted for the size and shape of its substrates. The architecture of the active site of 1A2 is characterized by multiple residues on helices F and I that constitutes two parallel substrate binding platforms on either side of the cavity. A large interindividual variability in the expression and activity of CYP1A2 has been observed, which is largely caused by genetic, epigenetic and environmental factors (e.g., smoking). CYP1A2 is primarily regulated by the aromatic hydrocarbon receptor (AhR) and CYP1A2 is induced through AhR-mediated transactivation following ligand binding and nuclear translocation. Induction or inhibition of CYP1A2 may provide partial explanation for some clinical drug interactions. To date, more than 15 variant alleles and a series of subvariants of the CYP1A2 gene have been identified and some of them have been associated with altered drug clearance and response and disease susceptibility. Further studies are warranted to explore the clinical and toxicological significance of altered CYP1A2 expression and activity caused by genetic, epigenetic, and environmental factors.
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Affiliation(s)
- Shu-Feng Zhou
- Discpline of Chinese Medicine, School of Health Sciences, RMIT University, Bundoora, Victoria 3083, Australia.
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Rydberg P, Vasanthanathan P, Oostenbrink C, Olsen L. Fast prediction of cytochrome P450 mediated drug metabolism. ChemMedChem 2010; 4:2070-9. [PMID: 19852016 DOI: 10.1002/cmdc.200900363] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cytochrome P450 mediated metabolism of drugs is one of the major determinants of their kinetic profile, and prediction of this metabolism is therefore highly relevant during the drug discovery and development process. A new rule-based method, based on results from density functional theory calculations, for predicting activation energies for aliphatic and aromatic oxidations by cytochromes P450 is developed and compared with several other methods. Although the applicability of the method is currently limited to a subset of P450 reactions, these reactions describe more than 90 % of the metabolites. The rules employed are relatively few and general, and when combined with solvent-accessible surface area calculations to account for steric accessibility, the method gives a major P450 metabolite as first-ranked position for 75 % of the substrates, and ranked in the top three for 90 % of substrates for a set of 20 substrates. In combination with docking, it can predict isoform-specific metabolism, and we apply this on CYP1A2 with very good results on 81 substrates, for which we find a major metabolite ranked in the top three for 90 % of the substrates (100 % in the training set and 87 % in the larger test set).
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Affiliation(s)
- Patrik Rydberg
- Department of Medicinal Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
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Ueng YF, Tsai CC, Lo WS, Yun CH. Induction of Hepatic Cytochrome P450s by the Herbal Medicine Sophora flavescens Extract in Rats: Impact on the Elimination of Theophylline. Drug Metab Pharmacokinet 2010; 25:560-7. [DOI: 10.2133/dmpk.dmpk-10-rg-055] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Zhou SF, Liu JP, Chowbay B. Polymorphism of human cytochrome P450 enzymes and its clinical impact. Drug Metab Rev 2009; 41:89-295. [PMID: 19514967 DOI: 10.1080/03602530902843483] [Citation(s) in RCA: 502] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Pharmacogenetics is the study of how interindividual variations in the DNA sequence of specific genes affect drug response. This article highlights current pharmacogenetic knowledge on important human drug-metabolizing cytochrome P450s (CYPs) to understand the large interindividual variability in drug clearance and responses in clinical practice. The human CYP superfamily contains 57 functional genes and 58 pseudogenes, with members of the 1, 2, and 3 families playing an important role in the metabolism of therapeutic drugs, other xenobiotics, and some endogenous compounds. Polymorphisms in the CYP family may have had the most impact on the fate of therapeutic drugs. CYP2D6, 2C19, and 2C9 polymorphisms account for the most frequent variations in phase I metabolism of drugs, since almost 80% of drugs in use today are metabolized by these enzymes. Approximately 5-14% of Caucasians, 0-5% Africans, and 0-1% of Asians lack CYP2D6 activity, and these individuals are known as poor metabolizers. CYP2C9 is another clinically significant enzyme that demonstrates multiple genetic variants with a potentially functional impact on the efficacy and adverse effects of drugs that are mainly eliminated by this enzyme. Studies into the CYP2C9 polymorphism have highlighted the importance of the CYP2C9*2 and *3 alleles. Extensive polymorphism also occurs in other CYP genes, such as CYP1A1, 2A6, 2A13, 2C8, 3A4, and 3A5. Since several of these CYPs (e.g., CYP1A1 and 1A2) play a role in the bioactivation of many procarcinogens, polymorphisms of these enzymes may contribute to the variable susceptibility to carcinogenesis. The distribution of the common variant alleles of CYP genes varies among different ethnic populations. Pharmacogenetics has the potential to achieve optimal quality use of medicines, and to improve the efficacy and safety of both prospective and currently available drugs. Further studies are warranted to explore the gene-dose, gene-concentration, and gene-response relationships for these important drug-metabolizing CYPs.
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Affiliation(s)
- Shu-Feng Zhou
- School of Health Sciences, RMIT University, Bundoora, Victoria, Australia.
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Monostory K, Pascussi JM, Kóbori L, Dvorak Z. Hormonal regulation of CYP1A expression. Drug Metab Rev 2009; 41:547-72. [DOI: 10.1080/03602530903112284] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Chang SY, Chen C, Yang Z, Rodrigues AD. Further Assessment of 17α-Ethinyl Estradiol as an Inhibitor of Different Human Cytochrome P450 Forms in Vitro. Drug Metab Dispos 2009; 37:1667-75. [DOI: 10.1124/dmd.109.026997] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Brown CM, Reisfeld B, Mayeno AN. Cytochromes P450: A Structure-Based Summary of Biotransformations Using Representative Substrates. Drug Metab Rev 2008. [DOI: 10.1080/03602530701836662] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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