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Rademeyer KM, R Nass S, Jones AM, Ohene-Nyako M, Hauser KF, McRae M. Fentanyl dysregulates neuroinflammation and disrupts blood-brain barrier integrity in HIV-1 Tat transgenic mice. J Neurovirol 2024; 30:1-21. [PMID: 38280928 PMCID: PMC11232468 DOI: 10.1007/s13365-023-01186-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 10/29/2023] [Accepted: 11/16/2023] [Indexed: 01/29/2024]
Abstract
Opioid overdose deaths have dramatically increased by 781% from 1999 to 2021. In the setting of HIV, opioid drug abuse exacerbates neurotoxic effects of HIV in the brain, as opioids enhance viral replication, promote neuronal dysfunction and injury, and dysregulate an already compromised inflammatory response. Despite the rise in fentanyl abuse and the close association between opioid abuse and HIV infection, the interactive comorbidity between fentanyl abuse and HIV has yet to be examined in vivo. The HIV-1 Tat-transgenic mouse model was used to understand the interactive effects between fentanyl and HIV. Tat is an essential protein produced during HIV that drives the transcription of new virions and exerts neurotoxic effects within the brain. The Tat-transgenic mouse model uses a glial fibrillary acidic protein (GFAP)-driven tetracycline promoter which limits Tat production to the brain and this model is well used for examining mechanisms related to neuroHIV. After 7 days of fentanyl exposure, brains were harvested. Tight junction proteins, the vascular cell adhesion molecule, and platelet-derived growth factor receptor-β were measured to examine the integrity of the blood brain barrier. The immune response was assessed using a mouse-specific multiplex chemokine assay. For the first time in vivo, we demonstrate that fentanyl by itself can severely disrupt the blood-brain barrier and dysregulate the immune response. In addition, we reveal associations between inflammatory markers and tight junction proteins at the blood-brain barrier.
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Affiliation(s)
- Kara M Rademeyer
- Department of Pharmacotherapy and Outcomes Science, Virginia Commonwealth University, Richmond, VA, 23298, U.S.A
| | - Sara R Nass
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, U.S.A
| | - Austin M Jones
- Department of Pharmacotherapy and Outcomes Science, Virginia Commonwealth University, Richmond, VA, 23298, U.S.A
| | - Michael Ohene-Nyako
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, U.S.A
| | - Kurt F Hauser
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, U.S.A
| | - MaryPeace McRae
- Department of Neuroscience, School of Medicine, University of Virginia, Charlottesville, VA, 22908, U.S.A..
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2
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Ona G, Reverte I, Rossi GN, Dos Santos RG, Hallak JE, Colomina MT, Bouso JC. Main targets of ibogaine and noribogaine associated with its putative anti-addictive effects: A mechanistic overview. J Psychopharmacol 2023; 37:1190-1200. [PMID: 37937505 DOI: 10.1177/02698811231200882] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
BACKGROUND There is a growing interest in studying ibogaine (IBO) as a potential treatment for substance use disorders (SUDs). However, its clinical use has been hindered for mainly two reasons: First, the lack of randomized, controlled studies informing about its safety and efficacy. And second, IBO's mechanisms of action remain obscure. It has been challenging to elucidate a predominant mechanism of action responsible for its anti-addictive effects. OBJECTIVE To describe the main targets of IBO and its main metabolite, noribogaine (NOR), in relation to their putative anti-addictive effects, reviewing the updated literature available. METHODS A comprehensive search involving MEDLINE and Google Scholar was undertaken, selecting papers published until July 2022. The inclusion criteria were both theoretical and experimental studies about the pharmacology of IBO. Additional publications were identified in the references of the initial papers. RESULTS IBO and its main metabolite, NOR, can modulate several targets associated with SUDs. Instead of identifying key targets, the action of IBO should be understood as a complex modulation of multiple receptor systems, leading to potential synergies. The elucidation of IBO's pharmacology could be enhanced through the application of methodologies rooted in the polypharmacology paradigm. Such approaches possess the capability to describe multifaceted patterns within multi-target drugs. CONCLUSION IBO displays complex effects through multiple targets. The information detailed here should guide future research on both mechanistic and therapeutic studies.
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Affiliation(s)
- Genís Ona
- International Center for Ethnobotanical Education, Research, and Service (ICEERS), Barcelona, Spain
- Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira i Virgili, Tarragona, Spain
- Medical Anthropology Research Center (MARC), Universitat Rovira i Virgili, Tarragona, Spain
| | - Ingrid Reverte
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Rome, Italy
| | - Giordano N Rossi
- Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Rafael G Dos Santos
- Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
- National Institute for Translational Medicine (INCT-TM), CNPq, Ribeirão Preto (SP), Brazil
| | - Jaime Ec Hallak
- Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
- National Institute for Translational Medicine (INCT-TM), CNPq, Ribeirão Preto (SP), Brazil
| | - Maria Teresa Colomina
- Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira i Virgili, Tarragona, Spain
| | - José Carlos Bouso
- International Center for Ethnobotanical Education, Research, and Service (ICEERS), Barcelona, Spain
- Medical Anthropology Research Center (MARC), Universitat Rovira i Virgili, Tarragona, Spain
- Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
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Wang XM, Wang J, Fokina V, Patrikeeva S, Rytting E, Ahmed MS, La JH, Nanovskaya T. Effect of deuteration on the single dose pharmacokinetic properties and postoperative analgesic activity of methadone. Drug Metab Pharmacokinet 2022; 47:100477. [PMID: 36368298 PMCID: PMC9886271 DOI: 10.1016/j.dmpk.2022.100477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 02/01/2023]
Abstract
Although methadone is effective in the management of acute pain, the complexity of its absorption-distribution-metabolism-excretion profile limits its use as an opioid of choice for perioperative analgesia. Because deuteration is known to improve the pharmacokinetic, pharmacodynamic and toxicological properties of some drugs, here we characterized the single dose pharmacokinetic properties and post-operative analgesic efficacy of d9-methadone. The pharmacokinetic profiles of d9-methadone and methadone administered intravenously to CD-1 male mice revealed that deuteration leads to a 5.7- and 4.4-fold increase in the area under the time-concentration curve and maximum concentration in plasma, respectively, as well as reduction in clearance (0.9 ± 0.3 L/h/kg vs 4.7 ± 0.8 L/h/kg). The lower brain-to-plasma ratio of d9-methadone compared to that of methadone (0.35 ± 0.12 vs 2.05 ± 0.62) suggested that deuteration decreases the transfer of the drug across the blood-brain barrier. The estimated LD50 value for a single intravenous dose of d9-methadone was 2.1-fold higher than that for methadone. Moreover, d9-methadone outperformed methadone in the efficacy against postoperative pain by primarily activating peripheral opioid receptors. Collectively, these data suggest that the replacement of three hydrogen atoms in three methyl groups of methadone altered its pharmacokinetic properties, improved safety, and enhanced its analgesic efficacy.
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Affiliation(s)
- Xiao-Ming Wang
- Maternal-Fetal Pharmacology and Bio-Development Laboratories, Department of Obstetrics & Gynecology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Jigong Wang
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Valentina Fokina
- Maternal-Fetal Pharmacology and Bio-Development Laboratories, Department of Obstetrics & Gynecology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Svetlana Patrikeeva
- Maternal-Fetal Pharmacology and Bio-Development Laboratories, Department of Obstetrics & Gynecology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Erik Rytting
- Maternal-Fetal Pharmacology and Bio-Development Laboratories, Department of Obstetrics & Gynecology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Mahmoud S Ahmed
- Maternal-Fetal Pharmacology and Bio-Development Laboratories, Department of Obstetrics & Gynecology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Jun-Ho La
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Tatiana Nanovskaya
- Maternal-Fetal Pharmacology and Bio-Development Laboratories, Department of Obstetrics & Gynecology, University of Texas Medical Branch, Galveston, TX, 77555, USA.
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4
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Drug Interactions. Forensic Toxicol 2022. [DOI: 10.1016/b978-0-12-819286-3.00003-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Akbari P, Najafi M, Rezaei AM, Miladi-Gorji H. Enriched Environment Ameliorates Cognitive Deficits and Locomotor Sensitization in Morphine-Withdrawn Rats Receiving Methadone Maintenance Treatment. Neuropsychobiology 2021; 79:437-444. [PMID: 32248192 DOI: 10.1159/000506598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 02/15/2020] [Indexed: 11/19/2022]
Abstract
OBJECTIVE This study was designed to examine whether enriched environments (EE) would attenuate object recognition and spatial learning and memory deficits and locomotor sensitization induced by methadone maintenance treatment (MMT) in morphine-withdrawn rats. METHODS Male Wistar rats (170 ± 10 g) were injected with bi-daily doses (10 mg/kg, 12-h intervals) of morphine for 14 days. Rats receiving MMT were reared in the standard environment (SE) or EE during 30 days of morphine withdrawal. Then, the rats were tested for object recognition (the object recognition memory test, ORMT) and spatial learning and memory (the water maze) and then challenged with morphine (1 mg/kg, i.p.) and evaluated for locomotor activity (open-field box). RESULTS The results revealed that the dependent/saline/EE (D/Sal/EE) and D/methadone/EE (D/Meth/EE) rats exhibited significant preference for the new object (p = 0.006 and p = 0.049), spent more time in the target zone (p = 0.045 and p = 0.005) on the water maze, and displayed a lower level of distance traveled (p = 0.002 and p = 0.0001) compared to their control groups reared in SE. CONCLUSIONS We conclude that exposure to EE could ameliorate the object recognition and spatial memory deficits and also decrease locomotor sensitivity in morphine-withdrawn rats receiving MMT. Thus, EE may be beneficial in the treatment of addiction during MMT.
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Affiliation(s)
- Parastoo Akbari
- Faculty of Psychology and Educational Sciences, University of Semnan, Semnan, Iran
| | - Mahmoud Najafi
- Faculty of Psychology and Educational Sciences, University of Semnan, Semnan, Iran
| | - Ali-Mohammad Rezaei
- Faculty of Psychology and Educational Sciences, University of Semnan, Semnan, Iran
| | - Hossein Miladi-Gorji
- Laboratory of Animal Addiction Models, Research Center of Physiology, Semnan University of Medical Sciences, Semnan, Iran, .,Department of Physiology, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran,
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Ramli FF. Pharmacogenomics biomarkers for personalized methadone maintenance treatment: The mechanism and its potential use. Bosn J Basic Med Sci 2021; 21:145-154. [PMID: 32841585 PMCID: PMC7982063 DOI: 10.17305/bjbms.2020.4897] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/10/2020] [Indexed: 11/23/2022] Open
Abstract
Methadone has a wide pharmacokinetic interindividual variability, resulting in unpredicted treatment response. Pharmacogenomic biomarkers seem promising for personalized methadone maintenance treatment. The evidence supports the use of ABCB1 single-nucleotide polymorphism (SNP) 1236C>T with genotypes C/T or C/C (Jewish) and haplotypes AGCTT carrier, AGCGC heterozygote, or non-carrier (Caucasian), which have a predicted lower methadone dose requirement. In contrast, ABCB1 SNP 1236C>T with genotype T/T (Jewish); haplotypes AGCGC homozygote, AGCTT non-carrier (Caucasian), and ABCB1 3435C>T variant carrier; and haplotypes CGT, TTC, and TGT (Han Chinese) have a predicted higher methadone dose. For methadone plasma levels, ABCB1 diplotype non-CGC/TTT (Malay) predicted lower, and diplotype CGC/TTT (Malay), 3435C>T allelic carrier, haplotypes (CGT, TTC, TGT) (Han Chinese) predicted higher methadone levels. In terms of metabolism biomarkers, a lower methadone requirement was related to carriers of CYP2B6 genotypes *4(G/G) and *9(T/T) among Jewish patients, CYP2B6*9 genotype (T/T) and haplotypes (TA/TG); and CYP2C19(*2/*2,*2/*3, and *3/*3; Han Chinese). Higher methadone dose was observed in CYP2C19*1 allelic carriers (Han Chinese) and CYP2D6 ultrarapid metabolizer (Caucasian). Lower methadone levels were reported in CYP2B6 SNPs, haplotypes TTT, and AGATAA (Han Chinese), CYP2C19 genotype *1/*1 (Han Chinese), allelic carrier *1xN (Caucasian), and CYP3A4 genotype *1/*1 (Caucasian). Carriers of CYP2B6 genotype *6/*6 (Caucasian), CYP2B6 haplotypes ATGCAG and ATGCTG (Han Chinese), and CYP3A4 genotype *1/*1B (Caucasian) had predicted higher methadone plasma levels. Specific pharmacokinetics biomarkers have potential uses for personalized methadone treatment in specific populations.
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Affiliation(s)
- Fitri Fareez Ramli
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Cheras, Kuala Lumpur, Malaysia
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7
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Iwersen-Bergmann S, Plattner S, Hischke S, Müller A, Andresen-Streichert H, Jungen H, Erb R, Beer-Sandner B. Brain/blood ratios of methadone and ABCB1 polymorphisms in methadone-related deaths. Int J Legal Med 2021; 135:473-482. [PMID: 33454797 PMCID: PMC7870766 DOI: 10.1007/s00414-021-02502-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 01/04/2021] [Indexed: 01/16/2023]
Abstract
Methadone is an opioid that often leads to fatalities. Interpretation of toxicological findings can be challenging if no further information about the case history is available. The aims of this study were (1) to determine whether brain/blood ratios can assist in the interpretation of methadone findings in fatalities; (2) to examine whether polymorphisms in the gene encoding the P-glycoprotein (also known as multidrug resistance protein 1 (MDR1) or ATP-binding cassette sub-family B member 1 (ABCB1)), which functions as a multispecific efflux pump in the blood–brain barrier, affect brain/blood ratios of methadone. Femoral venous blood and brain tissue (medulla oblongata and cerebellum) from 107 methadone-related deaths were analysed for methadone by gas chromatography-mass spectrometry. In addition, all the samples were genotyped for three common ABCB1 single nucleotide polymorphisms (SNPs rs1045642, rs1128503, and rs2032582) using ion-pair reversed-phase high-performance liquid chromatography-electrospray ionization mass spectrometry (ICEMS). In nearly all cases, methadone concentrations were higher in the brain than in the blood. Inter-individual brain/blood ratios varied (0.6–11.6); the mean ratio was 2.85 (standard deviation 1.83, median 2.35). Moreover, significant differences in mean brain/blood ratios were detected among the synonymous genotypes of rs1045642 in ABCB1 (p = 0.001). Cases with the T/T genotype had significantly higher brain/blood ratios than cases with the other genotypes (T/T vs. T/C difference (d) = 1.54, 95% CI [1.14, 2.05], p = 0.002; T/T vs. C/C d = 1.60, 95% CI [1.13, 2.29], p = 0.004). Our results suggest that the rs1045642 polymorphisms in ABCB1 may affect methadone concentrations in the brain and its site of action and may be an additional factor influencing methadone toxicity.
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Affiliation(s)
- S Iwersen-Bergmann
- Department of Legal Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany.
| | - S Plattner
- Institute of Legal Medicine, Innsbruck Medical University, Innsbruck, Austria
| | - S Hischke
- Institute for Health Services Research in Dermatology and Nursing, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - A Müller
- Department of Legal Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - H Andresen-Streichert
- Institute of Legal Medicine, Faculty of Medicine, University of Cologne, Köln, Germany
| | - H Jungen
- Department of Legal Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - R Erb
- Institute of Legal Medicine, Innsbruck Medical University, Innsbruck, Austria
| | - B Beer-Sandner
- Institute of Legal Medicine, Innsbruck Medical University, Innsbruck, Austria
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8
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Vázquez M, Guevara N, Maldonado C, Guido PC, Schaiquevich P. Potential Pharmacokinetic Drug-Drug Interactions between Cannabinoids and Drugs Used for Chronic Pain. BIOMED RESEARCH INTERNATIONAL 2020; 2020:3902740. [PMID: 32855964 PMCID: PMC7443220 DOI: 10.1155/2020/3902740] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/27/2020] [Accepted: 07/31/2020] [Indexed: 12/18/2022]
Abstract
Choosing an appropriate treatment for chronic pain remains problematic, and despite the available medication for its treatment, still, many patients complain about pain and appeal to the use of cannabis derivatives for pain control. However, few data have been provided to clinicians about the pharmacokinetic drug-drug interactions of cannabinoids with other concomitant administered medications. Therefore, the aim of this brief review is to assess the interactions between cannabinoids and pain medication through drug transporters (ATP-binding cassette superfamily members) and/or metabolizing enzymes (cytochromes P450 and glucuronyl transferases).
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Affiliation(s)
- Marta Vázquez
- Departamento de Ciencias Farmacéuticas, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Natalia Guevara
- Departamento de Ciencias Farmacéuticas, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Cecilia Maldonado
- Departamento de Ciencias Farmacéuticas, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Paulo Cáceres Guido
- Unidad de Farmacocinética Clínica, Farmacia, Hospital de Pediatría JP Garrahan, Buenos Aires, Argentina
| | - Paula Schaiquevich
- Medicina de Precisión, Hospital de Pediatría JP Garrahan, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
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Vatter T, Klumpp L, Ganser K, Stransky N, Zips D, Eckert F, Huber SM. Against Repurposing Methadone for Glioblastoma Therapy. Biomolecules 2020; 10:biom10060917. [PMID: 32560384 PMCID: PMC7356722 DOI: 10.3390/biom10060917] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/08/2020] [Accepted: 06/11/2020] [Indexed: 02/06/2023] Open
Abstract
Methadone, which is used as maintenance medication for outpatient treatment of opioid dependence or as an analgesic drug, has been suggested by preclinical in vitro and mouse studies to induce cell death and sensitivity to chemo- or radiotherapy in leukemia, glioblastoma, and carcinoma cells. These data together with episodical public reports on long-term surviving cancer patients who use methadone led to a hype of methadone as an anti-cancer drug in social and public media. However, clinical evidence for a tumoricidal effect of methadone is missing and prospective clinical trials, except in colorectal cancer, are not envisaged because of the limited preclinical data available. The present article reviews the pharmacokinetics, potential molecular targets, as well as the evidence for a tumoricidal effect of methadone in view of the therapeutically achievable doses in the brain. Moreover, it provides original in vitro data showing that methadone at clinically relevant concentrations fails to impair clonogenicity or radioresistance of glioblastoma cells.
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Affiliation(s)
- Tatjana Vatter
- Department of Radiation Oncology, University of Tübingen, 72076 Tübingen, Germany; (T.V.); (L.K.); (K.G.); (N.S.); (D.Z.); (F.E.)
| | - Lukas Klumpp
- Department of Radiation Oncology, University of Tübingen, 72076 Tübingen, Germany; (T.V.); (L.K.); (K.G.); (N.S.); (D.Z.); (F.E.)
| | - Katrin Ganser
- Department of Radiation Oncology, University of Tübingen, 72076 Tübingen, Germany; (T.V.); (L.K.); (K.G.); (N.S.); (D.Z.); (F.E.)
| | - Nicolai Stransky
- Department of Radiation Oncology, University of Tübingen, 72076 Tübingen, Germany; (T.V.); (L.K.); (K.G.); (N.S.); (D.Z.); (F.E.)
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, 72076 Tübingen, Germany
| | - Daniel Zips
- Department of Radiation Oncology, University of Tübingen, 72076 Tübingen, Germany; (T.V.); (L.K.); (K.G.); (N.S.); (D.Z.); (F.E.)
- German Cancer Consortium (DKTK), Partner Site Tübingen, Tübingen, Germany, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Franziska Eckert
- Department of Radiation Oncology, University of Tübingen, 72076 Tübingen, Germany; (T.V.); (L.K.); (K.G.); (N.S.); (D.Z.); (F.E.)
- German Cancer Consortium (DKTK), Partner Site Tübingen, Tübingen, Germany, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Stephan M. Huber
- Department of Radiation Oncology, University of Tübingen, 72076 Tübingen, Germany; (T.V.); (L.K.); (K.G.); (N.S.); (D.Z.); (F.E.)
- Correspondence: ; Tel.: +49-(0)7071-29-82183
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10
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Fogaça MV, Fukumoto K, Franklin T, Liu RJ, Duman CH, Vitolo OV, Duman RS. N-Methyl-D-aspartate receptor antagonist d-methadone produces rapid, mTORC1-dependent antidepressant effects. Neuropsychopharmacology 2019; 44:2230-2238. [PMID: 31454827 PMCID: PMC6898593 DOI: 10.1038/s41386-019-0501-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 08/16/2019] [Accepted: 08/20/2019] [Indexed: 12/18/2022]
Abstract
Currently available antidepressants have a delayed onset and limited efficacy, highlighting the need for new, rapid and more efficacious agents. Ketamine, an NMDA receptor antagonist, has emerged as a new rapid-acting antidepressant, effective even in treatment resistant patients. However, ketamine induces undesired psychotomimetic and dissociative side effects that limit its clinical use. The d-stereoisomer of methadone (dextromethadone; REL-1017) is a noncompetitive NMDA receptor antagonist with an apparently favorable safety and tolerability profile. The current study examined the rapid and sustained antidepressant actions of d-methadone in several behavioral paradigms, as well as on mTORC1 signaling and synaptic changes in the medial prefrontal cortex (mPFC). A single dose of d-methadone promoted rapid and sustained antidepressant responses in the novelty-suppressed feeding test (NSFT), a measure of anxiety, and in the female urine sniffing test (FUST), a measure of motivation and reward. D-methadone also produced a rapid reversal of the sucrose preference deficit, a measure of anhedonia, in rats exposed to chronic unpredictable stress. D-methadone increased phospho-p70S6 kinase, a downstream target of mTORC1 in the mPFC, and intra-mPFC infusion of the selective mTORC1 inhibitor rapamycin blocked the antidepressant actions of d-methadone in the FUST and NSFT. D-methadone administration also increased levels of the synaptic proteins, PSD95, GluA1, and Synapsin 1 and enhanced synaptic function in the mPFC. Studies in primary cortical cultures show that d-methadone also increases BDNF release, as well as phospho-p70S6 kinase. These findings indicate that d-methadone induces rapid antidepressant actions through mTORC1-mediated synaptic plasticity in the mPFC similar to ketamine.
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Affiliation(s)
- Manoela V. Fogaça
- 0000000419368710grid.47100.32Department of Psychiatry, Yale University School of Medicine, 34 Park Street, New Haven, CT 06520 USA
| | - Kenichi Fukumoto
- 0000000419368710grid.47100.32Department of Psychiatry, Yale University School of Medicine, 34 Park Street, New Haven, CT 06520 USA
| | - Tina Franklin
- 0000000419368710grid.47100.32Department of Psychiatry, Yale University School of Medicine, 34 Park Street, New Haven, CT 06520 USA
| | - Rong-Jian Liu
- 0000000419368710grid.47100.32Department of Psychiatry, Yale University School of Medicine, 34 Park Street, New Haven, CT 06520 USA
| | - Catharine H. Duman
- 0000000419368710grid.47100.32Department of Psychiatry, Yale University School of Medicine, 34 Park Street, New Haven, CT 06520 USA
| | - Ottavio V. Vitolo
- Relmada Therapeutics Inc., 880 Third Ave, 12th floor, New York, NY 10022 USA
| | - Ronald S. Duman
- 0000000419368710grid.47100.32Department of Psychiatry, Yale University School of Medicine, 34 Park Street, New Haven, CT 06520 USA
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Hammad AM, Alasmari F, Sari Y, Scott Hall F, Tiwari AK. Alcohol and Cocaine Exposure Modulates ABCB1 and ABCG2 Transporters in Male Alcohol-Preferring Rats. Mol Neurobiol 2019; 56:1921-1932. [PMID: 29978425 PMCID: PMC7780301 DOI: 10.1007/s12035-018-1153-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 05/24/2018] [Indexed: 11/27/2022]
Abstract
Two efflux transporters, ATP-binding cassettes B1 (ABCB1) and G2 (ABCG2), are highly expressed in the endothelial cells of the brain, where they regulate the bioavailability and distribution of several endogenous and xenobiotic compounds. However, whether ABCB1 or ABCG2 has any link with drug dependence, drug withdrawal effects, or the incidence of adverse effects in drug abuser is not known. In this study, we determined the effects of voluntary ethanol consumption following repeated exposure to cocaine or vehicle on the relative mRNA and protein expression of Abcg2/ABCG2 and Abcb1/ABCB1 in the nucleus accumbens (NAc) and medial prefrontal cortex (mPFC) of male alcohol-preferring (P) rats. Male P rats were allowed free choice access to ethanol (15 and 30% v/v) and water for 5 weeks to establish baseline drinking behavior. The following week, rats were either injected with 20 mg/kg i.p. of cocaine or saline, once a day, for 7 days. The relative mRNA and protein expression of Abcb1/ABCB1 and Abcg2/ABCG2 in the NAc and mPFC were significantly decreased in ethanol-saline- and ethanol-cocaine-exposed rats compared to control rats that received neither ethanol nor cocaine. Thus, prolonged exposure to commonly abused drugs, ethanol and cocaine, alters the expression of Abcb1/ABCB1 and Abcg2/ABCG2 mRNA and protein levels in brain areas that play a role in drug dependence.
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Affiliation(s)
- Alaa M Hammad
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Health Science Campus, 3000 Arlington Avenue, Toledo, OH, 43614, USA
- Department of Pharmacy, College of Pharmacy, Al-Zaytoonah University of Jordan, Amman, Jordan
| | - Fawaz Alasmari
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Health Science Campus, 3000 Arlington Avenue, Toledo, OH, 43614, USA
| | - Youssef Sari
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Health Science Campus, 3000 Arlington Avenue, Toledo, OH, 43614, USA
| | - F Scott Hall
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Health Science Campus, 3000 Arlington Avenue, Toledo, OH, 43614, USA
| | - Amit K Tiwari
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Health Science Campus, 3000 Arlington Avenue, Toledo, OH, 43614, USA.
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12
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Heinrich A, Zhong XB, Rasmussen TP. Variability in expression of the human MDR1 drug efflux transporter and genetic variation of the ABCB1 gene: implications for drug-resistant epilepsy. CURRENT OPINION IN TOXICOLOGY 2018; 11-12:35-42. [PMID: 31602418 DOI: 10.1016/j.cotox.2018.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Among individuals diagnosed with epilepsy, as many as one in three develop resistance to antiepileptic drugs (AEDs) thus rendering their seizures refractory to treatment. Despite current antiepileptic drugs (AEDs) having a variety of modes of action, seizures in drug-resistant individuals often persist even after treatment with two or more drugs. The underlying cause of this broad resistance is currently under debate, but two dominant theories have emerged and have been widely studied. Here we discuss current literature investigating the "transporter theory", the idea that individuals present with drug resistance due to genetic variability in the ABCB1 gene encoding the efflux transporter multidrug resistance protein 1 (MDR1). Results of in vitro and in vivo studies suggest that variability in the expression of the MDR1 transporter may be closely tied to drug resistance. While there is much support for this hypothesis from molecular and mechanistic studies, population-based studies of ABCB1 polymorphisms are divergent in their conclusions, and there is need for additional investigations.
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Affiliation(s)
- Anna Heinrich
- Department of Physiology and Neurobiology, the University of Connecticut, Storrs, CT 06269, USA
| | - Xiao-Bo Zhong
- Department of Pharmaceutical Sciences, School of Pharmacy, the University of Connecticut, Storrs, CT 06269, USA
| | - Theodore P Rasmussen
- Department of Pharmaceutical Sciences, School of Pharmacy, the University of Connecticut, Storrs, CT 06269, USA
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13
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Volpe DA, Xu Y, Sahajwalla CG, Younis IR, Patel V. Methadone Metabolism and Drug-Drug Interactions: In Vitro and In Vivo Literature Review. J Pharm Sci 2018; 107:2983-2991. [PMID: 30205091 DOI: 10.1016/j.xphs.2018.08.025] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 08/20/2018] [Accepted: 08/24/2018] [Indexed: 11/19/2022]
Abstract
Methadone is utilized for the treatment of individuals with opiate dependence. Methadone undergoes N-demethylation by multiple cytochrome P450 (CYP) enzymes including CYP3A4, CYP2B6, CYP2C19, CYP2D6, CYP2C9, and CYP2C8. In vivo, polymorphism effects on methadone systemic exposure have been noted for CYP2B6, CYP3A4, and CYP2D6. Clinical drug interaction studies with antiviral drugs in methadone maintenance treatment patients yield varying results on methadone pharmacokinetics and pharmacodynamics. In general, CYP inhibitors altered methadone exposure with no adverse effects. CYP inducers generally decreased methadone exposure with some reports of withdrawal symptoms in the subjects. Interaction studies with antiviral drug combinations yielding differing results depend on the enzyme(s) affected. For certain antiviral medicines which are dual inhibitor(s) and inducer(s) for CYP enzymes, their effect on methadone pharmacokinetics can change with time since the effect of induction is usually delayed compared to the effect of inhibition.
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Affiliation(s)
- Donna A Volpe
- Office of Clinical Pharmacology, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland 20993.
| | - Yun Xu
- Office of Clinical Pharmacology, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland 20993
| | - Chandrahas G Sahajwalla
- Office of Clinical Pharmacology, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland 20993
| | - Islam R Younis
- Office of Clinical Pharmacology, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland 20993
| | - Vikram Patel
- Office of Clinical Pharmacology, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland 20993
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14
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Myers MJ, Martinez M, Li F, Howard K, Yancy HF, Troutman L, Sharkey M. Impact of ABCB1 genotype in Collies on the pharmacokinetics of R- and S-fexofenadine. J Vet Pharmacol Ther 2018; 41:805-814. [PMID: 30020547 DOI: 10.1111/jvp.12696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 06/18/2018] [Indexed: 11/28/2022]
Abstract
Thirty-two Collies were used to determine the impact of ABCB1 genotype and phenotype on the plasma pharmacokinetics of fexofenadine's (Fex) R- and S-enantiomers after bolus Fex administration, as human P-gp exhibits stereoselectivity. Each Collie's ABCB1 genotype and ivermectin (IVM) sensitivity (phenotype) was determined prior to study enrolment. Wild-type (WT) Collies had lower plasma concentrations of the individual enantiomers as compared to heterozygous IVM nonsensitive (HNS), heterozygous IVM-sensitive (HS) and homozygous mutant (MUT) Collies. Based on pairwise statistical comparison, WT Collies had statistically significantly lower (AUC0-last ) and peak (Cmax ) values compared to HS, HNS and MUT Collies. Tmax was not influenced by genotype/phenotype. Inter-individual variability in PK metrics tended to be largest for WT Collies. Although the influence of genotype/phenotype on Fex PK occurred with the individual isomers, impairment of S-Fex absorption, particularly in the MUT dogs, exceeded that associated with R-Fex. Since Fex elimination occurs primarily via biliary excretion via a transporter other than P-glycoprotein, and based upon our understanding of Fex absorption kinetics, we attributed these differences primarily to the absorption portion of the profile. These differences are expressed in a stereo-specific manner. These results demonstrate the potential negative impact on estimates of drug effectiveness and toxicity, especially for P-gp substrates that do not exhibit Central Nervous System toxicities.
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Affiliation(s)
- Michael J Myers
- Office of Research, Division of Applied Veterinary Research, US Food and Drug Administration, Center for Veterinary Medicine, Laurel, Maryland
| | - Marilyn Martinez
- Office of New Animal Drug Evaluation, US Food and Drug Administration, Center for Veterinary Medicine, Rockville, Maryland
| | - Fei Li
- Office of Research, Division of Applied Veterinary Research, US Food and Drug Administration, Center for Veterinary Medicine, Laurel, Maryland
| | - Karyn Howard
- Office of Research, Division of Applied Veterinary Research, US Food and Drug Administration, Center for Veterinary Medicine, Laurel, Maryland
| | - Haile F Yancy
- Office of Research, Division of Applied Veterinary Research, US Food and Drug Administration, Center for Veterinary Medicine, Laurel, Maryland
| | - Lisa Troutman
- Office of New Animal Drug Evaluation, Division of Therapeutic Drugs for Non-food Animals, US Food and Drug Administration, Center for Veterinary Medicine, Rockville, Maryland
| | - Michele Sharkey
- Office of New Animal Drug Evaluation, Division of Therapeutic Drugs for Non-food Animals, US Food and Drug Administration, Center for Veterinary Medicine, Rockville, Maryland
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15
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Chaves C, Remiao F, Cisternino S, Decleves X. Opioids and the Blood-Brain Barrier: A Dynamic Interaction with Consequences on Drug Disposition in Brain. Curr Neuropharmacol 2018; 15:1156-1173. [PMID: 28474563 PMCID: PMC5725546 DOI: 10.2174/1570159x15666170504095823] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 04/04/2017] [Accepted: 04/25/2017] [Indexed: 12/28/2022] Open
Abstract
Background: Opioids are widely used in pain management, acting via opioid receptors and/or Toll-like receptors (TLR) present at the central nervous system (CNS). At the blood-brain barrier (BBB), several influx and efflux transporters, such as the ATP-binding cassette (ABC) P-glycoprotein (P-gp, ABCB1), Breast Cancer Resistance Protein (BCRP, ABCG2) and multidrug resistance-associated proteins (MRP, ABCC) transporters, and solute carrier transporters (SLC), are responsible for the transport of xenobiotics from the brain into the bloodstream or vice versa. Objective: ABC transporters export several clinically employed opioids, altering their neuro- pharmacokinetics and CNS effects. In this review, we explore the interactions between opioids and ABC transporters, and decipher the molecular mechanisms by which opioids can modify their expression at the BBB. Results: P-gp is largely implicated in the brain-to-blood efflux of opioids, namely morphine and oxycodone. Long-term ex-posure to morphine and oxycodone has proven to up-regulate the expression of ABC transporters, such as P-gp, BCRP and MRPs, at the BBB, which may lead to increased tolerance to the antinociceptive effects of such drugs. Recent studies uncov-er two mechanisms by which morphine may up-regulate P-gp and BCRP at the BBB: 1) via a glutamate, NMDA-receptor and COX-2 signaling cascade, and 2) via TLR4 activation, subsequent development of neuro- inflammation, and activation of NF-κB, presumably via glial cells. Conclusion: The BBB-opioid interaction can culminate in bilateral consequences, since ABC transporters condition the brain disposition of opioids, while opioids also affect the expression of ABC transporters at the BBB, which may result in increased CNS drug pharmacoresistance.
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Affiliation(s)
- Catarina Chaves
- Variabilite de Reponse Aux Psychotropes, INSERM, U1144, 75006 Paris, France.,Universite Paris Descartes, UMR-S 1144, Paris, F-75006, France.,Universite Paris Diderot, UMR-S 1144, Paris, F-75013, France.,REQUIMTE, Laboratorio de Toxicologia, Departamento de Ciencias Biologicas, Faculdade de Farmacia, Universidade do Porto, Porto, Portugal
| | - Fernando Remiao
- REQUIMTE, Laboratorio de Toxicologia, Departamento de Ciencias Biologicas, Faculdade de Farmacia, Universidade do Porto, Porto, Portugal
| | - Salvatore Cisternino
- Variabilite de Reponse Aux Psychotropes, INSERM, U1144, 75006 Paris, France.,Universite Paris Descartes, UMR-S 1144, Paris, F-75006, France.,Universite Paris Diderot, UMR-S 1144, Paris, F-75013, France.,Assistance Publique Hopitaux de Paris, AP-HP, Paris, France
| | - Xavier Decleves
- Variabilite de Reponse Aux Psychotropes, INSERM, U1144, 75006 Paris, France.,Universite Paris Descartes, UMR-S 1144, Paris, F-75006, France.,Universite Paris Diderot, UMR-S 1144, Paris, F-75013, France.,Assistance Publique Hopitaux de Paris, AP-HP, Paris, France
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16
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Brawanski K, Brockhoff G, Hau P, Vollmann-Zwerenz A, Freyschlag C, Lohmeier A, Riemenschneider MJ, Thomé C, Brawanski A, Proescholdt MA. Efficacy of D,L-methadone in the treatment of glioblastoma in vitro. CNS Oncol 2018; 7:CNS18. [PMID: 29916277 PMCID: PMC6200059 DOI: 10.2217/cns-2018-0006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 05/30/2018] [Indexed: 12/13/2022] Open
Abstract
AIM Recently, D,L-methadone has been put forward as adjuvant treatment in glioblastoma (GBM). METHODS We analyzed the μ-opioid receptor expression in a set of GBM cell lines and investigated the efficacy of D,L-methadone alone and in combination with temozolomide (TMZ). Results & conclusion: Expression of the μ-opioid receptor was similar in the tested cell lines. High concentrations of D,L-methadone induced apoptosis in all cell lines and showed treatment interaction with TMZ. However, in lower dosages, reflecting clinically attainable concentrations, D,L-methadone alone showed no efficacy, and induced even higher proliferation in one specific cell line. Also, no interaction with TMZ was observed. These results suggest caution to the premature use of D,L-methadone in the treatment of GBM patients.
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Affiliation(s)
| | - Gero Brockhoff
- Department of Gynecology & Obstetrics, University Hospital Regensburg, Regensburg, Germany
| | - Peter Hau
- Department of Neurology, University Hospital Regensburg, Regensburg, Germany
- Wilhelm Sander-NeuroOncology Unit, University Hospital Regensburg, Regensburg, Germany
| | - Arabel Vollmann-Zwerenz
- Department of Neurology, University Hospital Regensburg, Regensburg, Germany
- Wilhelm Sander-NeuroOncology Unit, University Hospital Regensburg, Regensburg, Germany
| | | | - Annette Lohmeier
- Wilhelm Sander-NeuroOncology Unit, University Hospital Regensburg, Regensburg, Germany
- Department of Neurosurgery, University Hospital Regensburg, Regensburg, Germany
| | - Markus J Riemenschneider
- Wilhelm Sander-NeuroOncology Unit, University Hospital Regensburg, Regensburg, Germany
- Department of Neuropathology, University Hospital Regensburg, Regensburg, Germany
| | - Claudius Thomé
- Department of Neurosurgery, University Hospital Innsbruck, Innsbruck, Austria
| | - Alexander Brawanski
- Wilhelm Sander-NeuroOncology Unit, University Hospital Regensburg, Regensburg, Germany
- Department of Neurosurgery, University Hospital Regensburg, Regensburg, Germany
| | - Martin A Proescholdt
- Wilhelm Sander-NeuroOncology Unit, University Hospital Regensburg, Regensburg, Germany
- Department of Neurosurgery, University Hospital Regensburg, Regensburg, Germany
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17
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Gibbs ME, Wilt LA, Ledwitch KV, Roberts AG. A Conformationally Gated Model of Methadone and Loperamide Transport by P-Glycoprotein. J Pharm Sci 2018; 107:1937-1947. [PMID: 29499278 DOI: 10.1016/j.xphs.2018.02.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 02/18/2018] [Accepted: 02/21/2018] [Indexed: 01/16/2023]
Abstract
P-glycoprotein (Pgp) is a multidrug resistance transporter that limits the penetration of a wide range of neurotherapeutics into the brain including opioids. The diphenylpropylamine opioids methadone and loperamide are structurally similar, but loperamide has about a 4-fold higher Pgp-mediated transport rate. In addition to these differences, they showed significant differences in their effects on Pgp-mediated adenosine triphosphate (ATP) hydrolysis. The activation of Pgp-mediated ATP hydrolysis by methadone was monophasic, whereas loperamide activation of ATP hydrolysis was biphasic implying methadone has a single binding site and loperamide has 2 binding sites on Pgp. Quenching of tryptophan fluorescence with these drugs and digoxin showed competition between the opioids and that loperamide does not compete for the digoxin-binding site. Acrylamide quenching of tryptophan fluorescence to probe Pgp conformational changes revealed that methadone- and loperamide-induced conformational changes were distinct. These results were used to develop a model for Pgp-mediated transport of methadone and loperamide where opioid binding and conformational changes are used to explain the differences in the opioid transport rates between methadone and loperamide.
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Affiliation(s)
- Morgan E Gibbs
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, Georgia 30602
| | - Laura A Wilt
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, Georgia 30602
| | - Kaitlyn V Ledwitch
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235
| | - Arthur G Roberts
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, Georgia 30602.
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18
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Noble F, Marie N. Management of Opioid Addiction With Opioid Substitution Treatments: Beyond Methadone and Buprenorphine. Front Psychiatry 2018; 9:742. [PMID: 30713510 PMCID: PMC6345716 DOI: 10.3389/fpsyt.2018.00742] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 12/14/2018] [Indexed: 12/13/2022] Open
Abstract
With the opioid crisis in North America, opioid addiction has come in the spotlight and reveals the weakness of the current treatments. Two main opioid substitution therapies (OST) exist: buprenorphine and methadone. These two molecules are mu opioid receptor agonists but with different pharmacodynamic and pharmacokinetic properties. In this review, we will go through these properties and see how they could explain why these medications are recognized for their efficacy in treating opioid addiction but also if they could account for the side effects especially for a long-term use. From this critical analysis, we will try to delineate some guidelines for the design of future OST.
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Affiliation(s)
- Florence Noble
- CNRS ERL 3649, "Neuroplasticité et thérapies des addictions", Paris, France.,INSERM UMR-S 1124, Paris, France.,Centre Universitaire des Saints Pères, Université Paris Descartes, Paris, France
| | - Nicolas Marie
- CNRS ERL 3649, "Neuroplasticité et thérapies des addictions", Paris, France.,INSERM UMR-S 1124, Paris, France.,Centre Universitaire des Saints Pères, Université Paris Descartes, Paris, France
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19
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Schaefer CP, Tome ME, Davis TP. The opioid epidemic: a central role for the blood brain barrier in opioid analgesia and abuse. Fluids Barriers CNS 2017; 14:32. [PMID: 29183383 PMCID: PMC5706290 DOI: 10.1186/s12987-017-0080-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 10/30/2017] [Indexed: 12/12/2022] Open
Abstract
Opioids are currently the primary treatment method used to manage both acute and chronic pain. In the past two to three decades, there has been a surge in the use, abuse and misuse of opioids. The mechanism by which opioids relieve pain and induce euphoria is dependent on the drug crossing the blood-brain barrier and accessing the central nervous system. This suggests the blood brain barrier plays a central role in both the benefits and risks of opioid use. The complex physiological responses to opioids that provide the benefits and drive the abuse also needs to be considered in the resolution of the opioid epidemic.
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Affiliation(s)
- Charles P. Schaefer
- Department of Pharmacology, University of Arizona, P.O. Box 245050, Tucson, AZ 85724 USA
| | - Margaret E. Tome
- Department of Pharmacology, University of Arizona, P.O. Box 245050, Tucson, AZ 85724 USA
| | - Thomas P. Davis
- Department of Pharmacology, University of Arizona, P.O. Box 245050, Tucson, AZ 85724 USA
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20
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Marie-Claire C, Jourdaine C, Lépine JP, Bellivier F, Bloch V, Vorspan F. Pharmacoepigenomics of opiates and methadone maintenance treatment: current data and perspectives. Pharmacogenomics 2017; 18:1359-1372. [DOI: 10.2217/pgs-2017-0040] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Current treatments of opioid addiction include primarily maintenance medications such as methadone. Chronic exposure to opiate and/or long-lasting maintenance treatment induce modulations of gene expression in brain and peripheral tissues. There is increasing evidence that epigenetic modifications underlie these modulations. This review summarizes published results on opioid-induced epigenetic changes in animal models and in patients. The epigenetic modifications observed with other drugs of abuse often used by opiate abusers are also outlined. Specific methadone maintenance treatment induced epigenetic modifications at different treatment stages may be combined with the ones resulting from patients’ substance use history. Therefore, research comparing groups of addicts with similar history and substances use disorders but contrasting for well-characterized treatment phenotypes should be encouraged.
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Affiliation(s)
- Cynthia Marie-Claire
- Variabilité de réponse aux psychotropes, INSERMU1144/Faculté de Pharmacie de Paris/Université Paris Descartes/Université ParisDiderot/Université Sorbonne Paris Cité, Paris, France
| | - Clément Jourdaine
- AP-HP, GH Saint-Louis – Lariboisière – F. Widal, Pôle de Psychiatrie et de Médecine Addictologique, 75475 Paris cedex 10, France
| | - Jean-Pierre Lépine
- AP-HP, GH Saint-Louis – Lariboisière – F. Widal, Pôle de Psychiatrie et de Médecine Addictologique, 75475 Paris cedex 10, France
| | - Frank Bellivier
- Variabilité de réponse aux psychotropes, INSERMU1144/Faculté de Pharmacie de Paris/Université Paris Descartes/Université ParisDiderot/Université Sorbonne Paris Cité, Paris, France
- AP-HP, GH Saint-Louis – Lariboisière – F. Widal, Pôle de Psychiatrie et de Médecine Addictologique, 75475 Paris cedex 10, France
| | - Vanessa Bloch
- Variabilité de réponse aux psychotropes, INSERMU1144/Faculté de Pharmacie de Paris/Université Paris Descartes/Université ParisDiderot/Université Sorbonne Paris Cité, Paris, France
| | - Florence Vorspan
- Variabilité de réponse aux psychotropes, INSERMU1144/Faculté de Pharmacie de Paris/Université Paris Descartes/Université ParisDiderot/Université Sorbonne Paris Cité, Paris, France
- AP-HP, GH Saint-Louis – Lariboisière – F. Widal, Pôle de Psychiatrie et de Médecine Addictologique, 75475 Paris cedex 10, France
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21
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Jagadeeshan S, David D, Jisha S, Manjula S, Asha Nair S. Solanum nigrum Unripe fruit fraction attenuates Adriamycin resistance by down-regulating multi-drug resistance protein (Mdr)-1 through Jak-STAT pathway. Altern Ther Health Med 2017; 17:370. [PMID: 28720093 PMCID: PMC5516375 DOI: 10.1186/s12906-017-1872-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 07/05/2017] [Indexed: 12/21/2022]
Abstract
Background Solanum nigrum, herbal plant that commonly grows in temperate climate zone, has been used as a traditional folk medicine whose ripen fruits were proven to exhibit anti-tumor properties. In traditional Chinese medicine, it has been used for centuries to cure inflammation, edema, mastitis and hepatic cancer and in the Ayurvedic system of traditional medicine in India, S. nigrum is applied against enteric diseases, ulcer, diarrhea and skin diseases. A methanolic glycosidic extract fraction of unripe fruit of S. nigrum (SNME) was investigated for its anticancer property and possible mechanism to surmount adriamycin resistance in NCI/ADR-RES cells. Methods The NCI/ADR-RES cells were treated with 7.8125, 15.625, 31.25, 62.5, 125 and 250 μg/ml of methanolic extract of S. nigrum (SNME) for 12, 24 and 48 h, to check the cell viability and proliferation. The cells were also exposed to adriamycin alone or in combination with SNME and the effects on cell growth were determined by MTT. Cell cycle analysis, Ethidium bromide and Acridine orange staining, Annexin-binding efficiency, nuclear condensation and DNA fragmentation of the apoptotic NCI/ADR-RES cells were also determined. To elucidate the relationship between SNME and multi drug resistance, we analyzed the expression levels of Mdr-1, JAK1, STAT3, and pSTAT3 in NCI/ADR-RES cells after treatment with SNME. Results Results from the cytotoxicity assay showed a direct correlation between the concentration of methanolic glycosidic extract fraction of S. nigrum (SNME) and the surviving cell population. Combination with Adriamycin, SNME exhibits a synergistic action on NCI/ADR-RES cells, giving the first line of evidence to overcoming Adriamycin resistance. The SNME mediated cell growth suppression was proven to be apoptotic, based on results obtained from DNA fragmentation, annexin V apoptosis assaay and PARP cleavage analysis. Looking into the molecular insight SNME surpasses the chemoresistance of NCI/ADR-RES cells by inhibiting the JAK-STAT3 signaling pathway through the down regulation of JAK1, STAT3, pSTAT3, and Mdr1 expression. Conclusions Collectively our findings suggest that unripe fruit of Solanum nigrum could possibly be used as a chemosensitizing agent against Adriamycin resistant cancers.
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22
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ABCB1 Polymorphisms and Cold Pressor Pain Responses: Opioid-Dependent Patients on Methadone Maintenance Therapy. Nurs Res 2017; 66:134-144. [PMID: 28252574 DOI: 10.1097/nnr.0000000000000204] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Methadone is a substrate of the P-glycoprotein efflux transporter, which is encoded by ABCB1 (MDR1), and thus, ABCB1 polymorphisms may influence the transport of methadone at the blood-brain barrier, affecting its adverse effects. OBJECTIVES This study investigated the association between ABCB1 polymorphisms and cold pressor pain responses among opioid-dependent patients on methadone maintenance therapy (MMT). METHODS Malay male opioid-dependent patients receiving MMT (n = 148) were recruited. Cold pressor pain responses (pain threshold, pain tolerance, and pain intensity) were measured at 0, 2, 4, 8, 12, and 24 hours post-methadone dose. DNA was extracted from whole blood and genotyped for ABCB1 polymorphisms including 1236C>T (rs1128503), 2677G>T/A (rs2032582), and 3435C>T (rs1045642) using the allelic discrimination real-time polymerase chain reaction. Repeated-measure analysis of variance between-group analysis was used to compare the three cold pressor pain responses and ABCB1 polymorphisms (1236C>T, 2677G>T/A, and 3435C>T) according to genotypes and allelic additive models, genotype dominant and recessive models, haplotypes, and diplotypes. RESULTS Patients with 2677 GG or 2677G allele had the lowest pain threshold compared with 2677G>T/A genotypes or alleles (p = .007 and .002, respectively). Haplotype analysis showed a significant association between ABCB1 haplotypes and pain threshold (p = .02). Patients with 2677G allele had the lowest pain tolerance compared to those with 2677T and 2677A alleles (2677G < 2677T < 2677A allele carriers; p = .05). In terms of pain intensity scores, patients with 2677 GG or 2677G allele had the highest scores compared to other 2677G>T/A genotypes or alleles (p = .04 and .008, respectively). Haplotype analysis revealed a significant difference between patients with CGC haplotype and those without this haplotype (p = .02). DISCUSSION To the best of our knowledge, this study provides the first evidence that ABCB1 polymorphisms are associated with cold pressor pain responses among Malay male patients with opioid dependence on MMT. The results may provide an initial prediction on heightened pain sensitivity or hyperalgesia for individuals who are carriers of the ABCB1 polymorphisms.
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Li F, Howard KD, Myers MJ. Influence of P-glycoprotein on the disposition of fexofenadine and its enantiomers. J Pharm Pharmacol 2017; 69:274-284. [PMID: 28090646 DOI: 10.1111/jphp.12687] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 11/26/2016] [Indexed: 11/27/2022]
Abstract
OBJECTIVES P-glycoprotein (P-gp) is responsible for the efflux of a broad variety of human and veterinary drugs. Canine P-gp polymorphisms alter drug disposition and toxicity, but their impact on the disposition of enantiomeric drugs is unknown. Using fexofenadine as a model compound, we developed and validated HPLC-fluorescence methods to determine the effect of P-gp on the disposition of fexofenadine and its enantiomers. METHODS A chiral CD-Ph column was used for the separation of (R) and (S)-fexofenadine. Determination of racemic fexofenadine was achieved on an XDB-CN column. Fexofenadine and its enantiomers were detected by fluorescence at the excitation wavelength of 220 nm and emission wavelength of 300 nm. These methods were used to measure concentrations of fexofenadine and its enantiomers in Collie plasma after oral administration. KEY FINDINGS This study demonstrates that P-gp prefers to transport (S)-fexofenadine, and P-gp deficiency causes the increase in both (R)-fexofenadine and (S)-fexofenadine in plasma. Racemic fexofenadine, (R)-fexofenadine and (S)-fexofenadine were increased in ABCB1-1Δ Collies (118.7, 72.0 and 48.3 ng/ml) compared to wild-type Collies (25.0, 16.5 and 7.7 ng/ml) at 1 h postadministration. The results demonstrate that the stereoselectivity of P-gp plays a key role in the disposition of fexofenadine enantiomers. CONCLUSIONS The information derived from this drug model will be used to determine whether additional safety or efficacy requirements are necessary for enantiomeric drugs that would be used in dogs or humans.
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Affiliation(s)
- Fei Li
- Division of Applied Veterinary Research, Office of Research, Center for Veterinary Medicine, U.S. Food and Drug Administration, Laurel, MD, USA
| | - Karyn D Howard
- Division of Applied Veterinary Research, Office of Research, Center for Veterinary Medicine, U.S. Food and Drug Administration, Laurel, MD, USA
| | - Michael J Myers
- Division of Applied Veterinary Research, Office of Research, Center for Veterinary Medicine, U.S. Food and Drug Administration, Laurel, MD, USA
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Abcb1 in Pigs: Molecular cloning, tissues distribution, functional analysis, and its effect on pharmacokinetics of enrofloxacin. Sci Rep 2016; 6:32244. [PMID: 27572343 PMCID: PMC5004175 DOI: 10.1038/srep32244] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 08/04/2016] [Indexed: 01/29/2023] Open
Abstract
P-glycoprotein (P-gp) is one of the best-known ATP-dependent efflux transporters, contributing to differences in pharmacokinetics and drug-drug interactions. Until now, studies on pig P-gp have been scarce. In our studies, the full-length porcine P-gp cDNA was cloned and expressed in a Madin-Darby Canine Kidney (MDCK) cell line. P-gp expression was then determined in tissues and its role in the pharmacokinetics of oral enrofloxacin in pigs was studied. The coding region of pig Abcb1 gene was 3,861 bp, encoding 1,286 amino acid residues (Mw = 141,966). Phylogenetic analysis indicated a close evolutionary relationship between porcine P-gp and those of cow and sheep. Pig P-gp was successfully stably overexpressed in MDCK cells and had efflux activity for rhodamine 123, a substrate of P-gp. Tissue distribution analysis indicated that P-gp was highly expressed in brain capillaries, small intestine, and liver. In MDCK-pAbcb1 cells, enrofloxacin was transported by P-gp with net efflux ratio of 2.48 and the efflux function was blocked by P-gp inhibitor verapamil. High expression of P-gp in the small intestine could modify the pharmacokinetics of orally administrated enrofloxacin by increasing the Cmax, AUC and Ka, which was demonstrated using verapamil, an inhibitor of P-gp.
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Zahari Z, Lee CS, Ibrahim MA, Musa N, Mohd Yasin MA, Lee YY, Tan SC, Mohamad N, Ismail R. Relationship between ABCB1 polymorphisms and serum methadone concentration in patients undergoing methadone maintenance therapy (MMT). THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2016; 42:587-596. [PMID: 27284701 DOI: 10.3109/00952990.2016.1172078] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Methadone is a substrate of the permeability glycoprotein (P-gp) efflux transporter, which is encoded by the ABCB1 (MDR1) gene. Large interindividual variability in serum methadone levels for therapeutic response has been reported. Genetic variations in ABCB1 gene may be responsible for the variability in observed methadone concentrations. OBJECTIVE This study investigated the associations of ABCB1 polymorphisms and serum methadone concentration over the 24-hour dosing interval in opioid-dependent patients on methadone maintenance therapy (MMT). METHODS One hundred and forty-eight male opioid-dependent patients receiving MMT were recruited. Genomic deoxyribonucleic acid (DNA) was extracted from whole blood and genotyped for ABCB1 polymorphisms [i.e. 1236C>T (dbSNP rs1128503), 2677G>T/A (dbSNP rs2032582), and 3435C>T (dbSNP rs1045642)] using the allelic discrimination real-time polymerase chain reaction (PCR). Blood samples were collected at 0, 0.5, 1, 2, 4, 8, 12, and 24 hours after the dose. Serum methadone concentrations were measured using the Methadone ELISA Kit. RESULTS Our results revealed an association of CGC/TTT diplotype (1236C>T, 2677G>T/A, and 3435C>T) with dose-adjusted serum methadone concentration over the 24-hour dosing interval. Patients with CGC/TTT diplotype had 32.9% higher dose-adjusted serum methadone concentration over the 24-hour dosing interval when compared with those without the diplotype [mean (SD) = 8.12 (0.84) and 6.11 (0.41) ng ml-1 mg-1, respectively; p = 0.033]. CONCLUSION There was an association between the CGC/TTT diplotype of ABCB1 polymorphisms and serum methadone concentration over the 24-hour dosing interval among patients on MMT. Genotyping of ABCB1 among opioid-dependent patients on MMT may help individualize and optimize methadone substitution treatment.
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Affiliation(s)
- Zalina Zahari
- a Department of Pharmacy , Hospital Universiti Sains Malaysia , Kelantan , Malaysia.,b Pharmacogenetics and Novel Therapeutics Cluster , Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM) , Kelantan , Malaysia
| | - Chee Siong Lee
- c Department of Emergency Medicine , School of Medical Sciences, USM , Kelantan , Malaysia
| | - Muslih Abdulkarim Ibrahim
- b Pharmacogenetics and Novel Therapeutics Cluster , Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM) , Kelantan , Malaysia.,d Department of Pharmacology and Toxicology , College of Pharmacy, Hawler Medical University , Hawler , Iraq
| | - Nurfadhlina Musa
- b Pharmacogenetics and Novel Therapeutics Cluster , Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM) , Kelantan , Malaysia
| | - Mohd Azhar Mohd Yasin
- b Pharmacogenetics and Novel Therapeutics Cluster , Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM) , Kelantan , Malaysia.,e Department of Psychiatry , School of Medical Sciences, USM , Kelantan , Malaysia
| | - Yeong Yeh Lee
- f School of Medical Sciences, USM , Kelantan , Malaysia
| | - Soo Choon Tan
- b Pharmacogenetics and Novel Therapeutics Cluster , Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM) , Kelantan , Malaysia
| | - Nasir Mohamad
- b Pharmacogenetics and Novel Therapeutics Cluster , Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM) , Kelantan , Malaysia.,g Faculty of Medicine & Health Sciences , Universiti Sultan Zainal Abidin , Terengganu , Malaysia
| | - Rusli Ismail
- b Pharmacogenetics and Novel Therapeutics Cluster , Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM) , Kelantan , Malaysia.,h Centre of Excellence for Research in AIDS (CERiA) , University of Malaya , Kuala Lumpur , Malaysia
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Holm KMD, Linnet K. Determination of the unbound fraction of R- and S-methadone in human brain. Int J Legal Med 2016; 130:1519-1526. [DOI: 10.1007/s00414-016-1365-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 03/29/2016] [Indexed: 10/22/2022]
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27
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Mouly S, Bloch V, Peoc'h K, Houze P, Labat L, Ksouda K, Simoneau G, Declèves X, Bergmann JF, Scherrmann JM, Laplanche JL, Lepine JP, Vorspan F. Methadone dose in heroin-dependent patients: role of clinical factors, comedications, genetic polymorphisms and enzyme activity. Br J Clin Pharmacol 2016; 79:967-77. [PMID: 25556837 DOI: 10.1111/bcp.12576] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 12/05/2014] [Accepted: 12/21/2014] [Indexed: 01/11/2023] Open
Abstract
AIMS Methadone is characterized by wide intersubject variability regarding the dose needed to obtain full therapeutic response. We assessed the influence of sociodemographic, ethnic, clinical, metabolic and genotypic variables on methadone maintenance dose requirement in opioid-dependent responder patients. METHODS Eighty-one stable patients (60 men and 21 women, 43.7 ± 8.1 years old, 63.1 ± 50.9 mg day(-1) methadone), divided into quartiles with respect to the median daily dose, were enrolled and underwent clinical examination, treatment history and determination of liver/intestinal cytochrome P450 (CYP) 3A4 activity measured by the midazolam test, R,S-methadone trough concentration and clinically significant polymorphisms of the OPRM1, DRD2, COMT, ABCB1, CYP2B6, CYP3A5, CYP2C19 and CYP2D6 genes. RESULTS Methadone maintenance dose was correlated to the highest dose ever used (r(2) = 0.57, P < 0.0001). Fractioned methadone intake (odds ratio 4.87, 95% confidence interval 1.27-18.6, P = 0.02), bodyweight (odds ratio 1.57, 95% confidence interval 1.01-2.44, P = 0.04), history of cocaine dependence (80 vs. 44 mg day(-1) in never-addict patients, P = 0.005) and ethnicity (Asian > Caucasian > African, P = 0.04) were independently associated with high-dose methadone in multiple regression analysis. A modest correlation was observed between liver/intestinal CYP3A4 activity and methadone dose at steady state (Spearman rank correlation coefficient [rs ] = 0.21, P = 0.06) but not with highest dose ever used (rs = 0.15, P = 0.18) or dose-normalized R,S-methadone trough concentrations (rs = -0.05, P = 0.64). Concomitant CYP3A4 inhibitors only affected the relationship between methadone dose and R,S-methadone trough concentration. None of the genetic polymorphisms explored was predictive of the methadone maintenance dose. CONCLUSIONS Methadone maintenance dose was predicted by sociodemographic and clinical variables rather than genetic polymorphisms or liver/intestinal CYP3A4 activity in stable patients.
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Affiliation(s)
- Stéphane Mouly
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France.,Unit of Therapeutic Research & Internal Medicine Department, Lariboisière-Saint Louis Hospital, Paris, France
| | - Vanessa Bloch
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France
| | - Katell Peoc'h
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France.,Laboratory of Biochemistry and Molecular Biology, Lariboisière-Saint Louis Hospital, Paris, France
| | - Pascal Houze
- Laboratory of Pharmacology, Lariboisière-Saint Louis Hospital, Paris, France
| | - Laurence Labat
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France
| | - Kamilia Ksouda
- Psychiatric Unit, Assistance Publique-Hôpitaux de Paris (APHP), Lariboisière-Saint Louis Hospital, Paris, France
| | - Guy Simoneau
- Unit of Therapeutic Research & Internal Medicine Department, Lariboisière-Saint Louis Hospital, Paris, France
| | - Xavier Declèves
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France
| | - Jean Francois Bergmann
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France.,Unit of Therapeutic Research & Internal Medicine Department, Lariboisière-Saint Louis Hospital, Paris, France
| | - Jean-Michel Scherrmann
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France
| | - Jean-Louis Laplanche
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France.,Laboratory of Biochemistry and Molecular Biology, Lariboisière-Saint Louis Hospital, Paris, France
| | - Jean-Pierre Lepine
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France.,Psychiatric Unit, Assistance Publique-Hôpitaux de Paris (APHP), Lariboisière-Saint Louis Hospital, Paris, France
| | - Florence Vorspan
- Inserm, U1144, Paris, F-75006, France.,Université Paris Descartes, UMR-S1144, Paris, F-75006, France.,Université Paris Diderot, UMR-S1144, Paris, F-75010, France.,Psychiatric Unit, Assistance Publique-Hôpitaux de Paris (APHP), Lariboisière-Saint Louis Hospital, Paris, France
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Marie-Claire C, Crettol S, Cagnard N, Bloch V, Mouly S, Laplanche JL, Bellivier F, Lepine JP, Eap C, Vorspan F. Variability of response to methadone: genome-wide DNA methylation analysis in two independent cohorts. Epigenomics 2016; 8:181-95. [DOI: 10.2217/epi.15.110] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Aim: Methadone maintenance treatment is characterized by large interindividual dose variability. The aim of this study was to evaluate whether DNA methylations are associated with daily dose of methadone. Materials & methods: Subjects stabilized at high (n = 12) or low (n = 12) methadone doses were selected from two independent cohorts (French and Swiss). DNA methylation patterns were analyzed using HumanMethylation450 BeadChips. Results: In total, 584 differentially methylated sites were identified in the French cohort corresponding to 352 genes. Of these, 26 were replicated in the Swiss cohort. The methylation status of 13 genes varied similarly in both cohorts and calcium signaling pathway was significantly enriched. Conclusion: Our results indicate that differentially methylated sites are associated with methadone daily dose and give insights into the molecular pathways underlying this interindividual dose variability.
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Affiliation(s)
- Cynthia Marie-Claire
- Inserm, UMR-S 1144, Paris, F-75006, France
- Université Paris Descartes, UMR-S 1144, Paris, F-75006, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S 1144, Paris, F-75013, France
| | - Severine Crettol
- Unit of Pharmacogenetics & Clinical Psychopharmacology, Centre for Psychiatric Neurosciences, Department of Psychiatry, Lausanne University, Hospital of Cery, Prilly-Lausanne, Switzerland
| | - Nicolas Cagnard
- Bioinformatics Platform Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Vanessa Bloch
- Inserm, UMR-S 1144, Paris, F-75006, France
- Université Paris Descartes, UMR-S 1144, Paris, F-75006, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S 1144, Paris, F-75013, France
| | - Stéphane Mouly
- Inserm, UMR-S 1144, Paris, F-75006, France
- Université Paris Descartes, UMR-S 1144, Paris, F-75006, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S 1144, Paris, F-75013, France
| | - Jean-Louis Laplanche
- Inserm, UMR-S 1144, Paris, F-75006, France
- Université Paris Descartes, UMR-S 1144, Paris, F-75006, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S 1144, Paris, F-75013, France
| | - Frank Bellivier
- Inserm, UMR-S 1144, Paris, F-75006, France
- Université Paris Descartes, UMR-S 1144, Paris, F-75006, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S 1144, Paris, F-75013, France
- Psychiatry Department, Fernand Widal Hospital, Assistance Publique - Hôpitaux de Paris, France
| | - Jean-Pierre Lepine
- Inserm, UMR-S 1144, Paris, F-75006, France
- Université Paris Descartes, UMR-S 1144, Paris, F-75006, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S 1144, Paris, F-75013, France
- Psychiatry Department, Fernand Widal Hospital, Assistance Publique - Hôpitaux de Paris, France
| | - Chin Eap
- Unit of Pharmacogenetics & Clinical Psychopharmacology, Centre for Psychiatric Neurosciences, Department of Psychiatry, Lausanne University, Hospital of Cery, Prilly-Lausanne, Switzerland
| | - Florence Vorspan
- Inserm, UMR-S 1144, Paris, F-75006, France
- Université Paris Descartes, UMR-S 1144, Paris, F-75006, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S 1144, Paris, F-75013, France
- Psychiatry Department, Fernand Widal Hospital, Assistance Publique - Hôpitaux de Paris, France
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Madadi P, Kelly LE, Ross CJ, Kepron C, Edwards JN, Koren G. Forensic Investigation of Methadone Concentrations in Deceased Breastfed Infants. J Forensic Sci 2015; 61:576-580. [PMID: 26513313 DOI: 10.1111/1556-4029.12972] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 02/16/2015] [Accepted: 04/11/2015] [Indexed: 11/29/2022]
Abstract
There is a paucity of data to aid in assessing whether postmortem methadone findings in breastfed infants are clinically and/or toxicologically significant. Two cases are reported in which methadone was detected in deceased neonates whose mothers were enrolled in methadone maintenance programs and were breastfeeding. In addition to a complete autopsy and toxicological testing for alcohol, prescription medications, and drugs of abuse, pharmacogenetic analysis was performed for variants in genes related to methadone metabolism and response. In both cases, the postmortem methadone concentration measured in neonatal heart blood was higher than the maximum serum methadone concentration reported in living breastfed infants whose mothers were receiving methadone. However, additional analysis of antemortem blood indicated postmortem redistribution of methadone. Pharmacogenetic results were suggestive of a potential predisposition to methadone toxicity based on studies in adults; the significance of these findings in breastfed neonates requires further research. The medical cause of death was unascertained in both cases.
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Affiliation(s)
- Parvaz Madadi
- Toxicology Section, Centre of Forensic Sciences, Toronto, ON, Canada
| | - Lauren E Kelly
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, and Ivey Chair in Molecular Toxicology, Western University, London, ON, Canada
| | - Colin J Ross
- Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada.,Child and Family Research Institute, University of British Columbia, Vancouver, BC, Canada.,Division of Translational Therapeutics, Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada
| | - Charis Kepron
- Ontario Forensic Pathology Service, Ottawa, ON, Canada
| | | | - Gideon Koren
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, and Ivey Chair in Molecular Toxicology, Western University, London, ON, Canada.,Division of Clinical Pharmacology and Toxicology, Department of Pediatrics, Hospital for Sick Children, Toronto, ON, Canada
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Gharavi R, Hedrich W, Wang H, Hassan HE. Transporter-Mediated Disposition of Opioids: Implications for Clinical Drug Interactions. Pharm Res 2015; 32:2477-502. [PMID: 25972096 DOI: 10.1007/s11095-015-1711-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 05/06/2015] [Indexed: 01/08/2023]
Abstract
Opioid-related deaths, abuse, and drug interactions are growing epidemic problems that have medical, social, and economic implications. Drug transporters play a major role in the disposition of many drugs, including opioids; hence they can modulate their pharmacokinetics, pharmacodynamics and their associated drug-drug interactions (DDIs). Our understanding of the interaction of transporters with many therapeutic agents is improving; however, investigating such interactions with opioids is progressing relatively slowly despite the alarming number of opioids-mediated DDIs that may be related to transporters. This review presents a comprehensive report of the current literature relating to opioids and their drug transporter interactions. Additionally, it highlights the emergence of transporters that are yet to be fully identified but may play prominent roles in the disposition of opioids, the growing interest in transporter genomics for opioids, and the potential implications of opioid-drug transporter interactions for cancer treatments. A better understanding of drug transporters interactions with opioids will provide greater insight into potential clinical DDIs and could help improve opioids safety and efficacy.
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Affiliation(s)
- Robert Gharavi
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 N Pine Street, Rooms: N525 (Office), Baltimore, Maryland, 21201, USA
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Influence of HIV antiretrovirals on methadone N-demethylation and transport. Biochem Pharmacol 2015; 95:115-25. [PMID: 25801005 DOI: 10.1016/j.bcp.2015.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 03/12/2015] [Indexed: 02/02/2023]
Abstract
Drug interactions involving methadone and/or HIV antiretrovirals can be problematic. Mechanisms whereby antiretrovirals induce clinical methadone clearance are poorly understood. Methadone is N-demethylated to 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) by CYP2B6 and CYP3A4 in vitro, but by CYP2B6 in vivo. This investigation evaluated human hepatocytes as a model for methadone induction, and tested the hypothesis that methadone and EDDP are substrates for human drug transporters. Human hepatocyte induction by several antiretrovirals of methadone N-demethylation, and CYP2B6 and CYP3A4 transcription, protein expression and catalytic activity, and pregnane X receptor (PXR) activation were evaluated. Methadone and EDDP uptake and efflux by overexpressed transporters were also determined. Methadone N-demethylation was generally not significantly increased by the antiretrovirals. CYP2B6 mRNA and activity (bupropion N-demethylation) were induced by several antiretrovirals, as were CYP3A4 mRNA and protein expression, but only indinavir increased CYP3A activity (alfentanil dealkylation). CYP upregulation appeared related to PXR activation. Methadone was not a substrate for uptake (OCT1, OCT2, OCT3, OATP1A2, OATP1B1, OATP1B3, OATP2B1) or efflux (P-gp, BCRP) transporters. EDDP was a good substrate for P-gp, BCRP, OCT1, OCT3, OATP1A2, and OATP1B1. OATP1A2- and OCT3-mediated EDDP uptake, and BCRP-mediated EDDP efflux transport, was inhibited by several antiretrovirals. Results show that hepatocyte methadone N-demethylation resembles expressed and liver microsomal metabolism more than clinical metabolism. Compared with clinical studies, hepatocytes underreport induction of methadone metabolism by HIV drugs. Hepatocytes are not a good predictive model for clinical antiretroviral induction of methadone metabolism and not a substitute for clinical studies. EDDP is a transporter substrate, and is susceptible to transporter-mediated interactions.
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Meissner K, Blood J, Francis AM, Yermolenka V, Kharasch ED. Cyclosporine-inhibitable cerebral drug transport does not influence clinical methadone pharmacodynamics. Anesthesiology 2015; 121:1281-91. [PMID: 25072223 DOI: 10.1097/aln.0000000000000391] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Interindividual variability and drug interaction studies suggest that blood-brain barrier drug transporters mediate human methadone brain biodistribution. In vitro and animal studies suggest that methadone is a substrate for the efflux transporter P-glycoprotein, and that P-glycoprotein-mediated transport influences brain access and pharmacologic effect. This investigation tested whether methadone is a transporter substrate in humans [corrected]. METHODS Healthy volunteers received oral (N=16) or IV (N=12) methadone in different crossover protocols after nothing (control) or the validated P-glycoprotein inhibitor cyclosporine (4.5 mg/kg orally twice daily for 4 days, or 5 mg/kg IV over 2 h). Plasma and urine methadone and metabolite concentrations were measured by mass spectrometry. Methadone effects were measured by miosis and thermal analgesia (maximally tolerated temperature and verbal analog scale rating of discreet temperatures). RESULTS Cyclosporine marginally but significantly decreased methadone plasma concentrations and apparent oral clearance, but had no effect on methadone renal clearance or on hepatic N-demethylation. Cyclosporine had no effect on miosis or on R-methadone concentration-miosis relationships after either oral or IV methadone. Peak miosis was similar in controls and cyclosporine-treated subjects after oral methadone (1.4±0.4 and 1.3±0.5 mm/mg, respectively) and IV methadone (3.1±1.0 and 3.2±0.8 mm, respectively). Methadone increased maximally tolerated temperature, but analgesia testing was confounded by cyclosporine-related pain. CONCLUSIONS Cyclosporine did not affect methadone pharmacodynamics. This result does not support a role for cyclosporine-inhibitable transporters mediating methadone brain access and biodistribution.
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Affiliation(s)
- Konrad Meissner
- From the Department of Anesthesiology, Universitätsmedizin Greifswald, Greifswald, Germany (K.M.); and Departments of Anesthesiology (K.M., J.B., A.M.F., V.Y., E.D.K.) and of Biochemistry and Molecular Biophysics (E.D.K.), Washington University in St. Louis, St. Louis, Missouri
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Bart G, Lenz S, Straka RJ, Brundage RC. Ethnic and genetic factors in methadone pharmacokinetics: a population pharmacokinetic study. Drug Alcohol Depend 2014; 145:185-93. [PMID: 25456329 PMCID: PMC4254688 DOI: 10.1016/j.drugalcdep.2014.10.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 10/16/2014] [Accepted: 10/16/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND Treatment of opiate use disorders with methadone is complicated by wide interindividual variability in pharmacokinetics. To identify potentially contributing covariates in methadone pharmacokinetics, we used population pharmacokinetic modeling to estimate clearance (CL/F) and volume of distribution (V/F) for each methadone enantiomer in an ethnically diverse methadone maintained population. METHODS Plasma levels of the opiate-active R-methadone and opiate-inactive S-methadone were measured in 206 methadone maintained subjects approximately two and twenty-three hours after a daily oral dose of rac-methadone. A linear one-compartment population pharmacokinetic model with first-order conditional estimation with interaction (FOCE-I) was used to evaluate methadone CL/F and V/F. The influence of covariates on parameter estimates was evaluated using stepwise covariate modeling. Covariates included ethnicity, gender, weight, BMI, age, methadone dose, and 21 single nucleotide polymorphisms in genes implicated in methadone pharmacokinetics. RESULTS In the final model, for each enantiomer, Hmong ethnicity reduced CL/F by approximately 30% and the rs2032582 (ABCB1 2677G>T/A) GG genotype was associated with a 20% reduction in CL/F. The presence of the rs3745274 minor allele (CYP2B6 515G>T) reduced CL/F by up to 20% for S-methadone only. A smaller effect of age was noted on CL/F for R-methadone. CONCLUSION This is the first report showing the influence of the rs2032582 and rs3745274 variants on methadone pharmacokinetics rather than simply dose requirements or plasma levels. Population pharmacokinetics is a valuable method for identifying the influences on methadone pharmacokinetic variability.
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Affiliation(s)
- Gavin Bart
- Department of Medicine, Hennepin County Medical Center, 701 Park Avenue, Minneapolis, MN 55415, USA.
| | - Scott Lenz
- Minneapolis Medical Research Foundation, 914 S 8th St., Minneapolis, MN 55404, USA
| | - Robert J. Straka
- Department of Experimental and Clinical Pharmacology, University of Minnesota College of Pharmacy, 5-130 Weaver-Densford Hall, 308 Harvard Street SE, Minneapolis, MN 55455, USA
| | - Richard C. Brundage
- Department of Experimental and Clinical Pharmacology, University of Minnesota College of Pharmacy, 5-130 Weaver-Densford Hall, 308 Harvard Street SE, Minneapolis, MN 55455, USA
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Holm KMD, Linnet K. Distribution of enantiomers of methadone and its main metabolite EDDP in human tissues and blood of postmortem cases. J Forensic Sci 2014; 60:95-101. [PMID: 25421110 DOI: 10.1111/1556-4029.12627] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 02/03/2014] [Accepted: 02/10/2014] [Indexed: 11/28/2022]
Abstract
Knowledge concerning the distribution of methadone in postmortem human tissue and the effect of postmortem redistribution on methadone is today limited making the choice of a suitable substitute for femoral blood difficult when this is not available. Cardiac blood, femoral blood, muscle, and brain tissue concentrations of the enantiomers of methadone and its metabolite 2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium were recorded for 155 postmortem cases. Brain and muscle tissue concentrations exceeded the femoral blood concentrations with a median fold of 2.3 and 1.6, respectively, but both had a better correlation than cardiac blood to femoral blood concentrations. The Kruskal-Wallis test showed a significant dependency on time and body mass index for some of the matrix ratios over femoral blood. We conclude brain or muscle tissue may constitute a better alternative for measurement of methadone than cardiac blood for situations in which femoral blood is not available, despite concentrations in both matrices being systematically higher.
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Affiliation(s)
- Karen Marie Dollerup Holm
- Section of Forensic Chemistry, Department of Forensic Medicine, Faculty of Health Sciences, University of Copenhagen, Frederik V's Vej 11, DK-2100, Copenhagen, Denmark
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Somogyi AA, Barratt DT, Ali RL, Coller JK. Pharmacogenomics of methadone maintenance treatment. Pharmacogenomics 2014; 15:1007-27. [DOI: 10.2217/pgs.14.56] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Methadone is the major opioid substitution therapy for opioid dependence. Dosage is highly variable and is often controlled by the patient and prescriber according to local and national policy and guidelines. Nevertheless many genetic factors have been investigated including those affecting its metabolism (CYP2B6-consistent results), efflux transport (P-gp-inconsistent results), target μ-opioid receptor (μ-opioid receptor-inconsistent results) and a host of other receptors (DRD2) and signaling elements (GIRK2 and ARRB2; not replicated). None by themselves have been able to substantially explain dosage variation (the major but not sole end point). When multiple genes have been combined such as ABCB1, CYP2B6, OPRM1 and DRD2 a greater contribution to dosage variation was found but not as yet replicated. As stabilization of dosage needs to be made rapidly, it is imperative that larger internationally based studies be instigated so that genetic contribution to dosage can be properly assessed, which may or may not tailor to different ethnic groups and each country’s policy towards an outcome that benefits all.
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Affiliation(s)
- Andrew A Somogyi
- Discipline of Pharmacology, School of Medical Sciences, Faculty of Health Sciences, University of Adelaide, Adelaide 5005, Australia
- Department of Clinical Pharmacology, Royal Adelaide Hospital, Adelaide, 5005, Australia
| | - Daniel T Barratt
- Discipline of Pharmacology, School of Medical Sciences, Faculty of Health Sciences, University of Adelaide, Adelaide 5005, Australia
| | - Robert L Ali
- Discipline of Pharmacology, School of Medical Sciences, Faculty of Health Sciences, University of Adelaide, Adelaide 5005, Australia
- DASSA World Health Organization Collaborating Centre for Research in the Treatment of Drug & Alcohol Problems, School of Medical Sciences, Faculty of Health Sciences, University of Adelaide, Adelaide 5005, Australia
| | - Janet K Coller
- Discipline of Pharmacology, School of Medical Sciences, Faculty of Health Sciences, University of Adelaide, Adelaide 5005, Australia
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Moving toward personalized medicine in the methadone maintenance treatment program: a pilot study on the evaluation of treatment responses in Taiwan. BIOMED RESEARCH INTERNATIONAL 2013; 2013:741403. [PMID: 24455721 PMCID: PMC3876825 DOI: 10.1155/2013/741403] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 11/25/2013] [Indexed: 12/26/2022]
Abstract
This pilot study simultaneously evaluated the effects of various factors, including genetic variations of CYP2B6, CYP2C19, and ABCB1, demographic characteristics, disease states, methadone-drug interactions (MDIs), and poly-substance use, on the treatment responses among non-HIV patients in the methadone maintenance treatment program (MMTP) in Taiwan. A total of 178 patients were recruited from two major hospitals that provided MMTP services in southern Taiwan, and information regarding concomitant medications and diseases was acquired from the National Health Insurance (NHI) program. The results demonstrated that the methadone maintenance dose, CYP2B6 785G allele, and ABCB1 2677T allele have positive effects on the methadone plasma concentration. In contrast, patients with HCV coinfection, alcohol problems, and psychiatric diseases may have a negative response to treatment. Thus, a comprehensive evaluation of treatment responses in the MMTP should include not only genetic polymorphisms in methadone metabolism and transporter proteins, but also concomitant diseases, MDIs, and poly-substance use. The results also suggest that personalized medicine may be indispensable for a better outcome of the MMTP.
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Wu SL, Wang SC, Tsou HH, Kuo HW, Ho IK, Liu SW, Hsu YT, Chang YS, Liu YL. Hepatitis C virus infection influences the S-methadone metabolite plasma concentration. PLoS One 2013; 8:e69310. [PMID: 23935979 PMCID: PMC3720619 DOI: 10.1371/journal.pone.0069310] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 06/07/2013] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND AND OBJECTIVES Heroin-dependent patients typically contract hepatitis C virus (HCV) at a disproportionately high level due to needle exchange. The liver is the primary target organ of HCV infection and also the main organ responsible for drug metabolism. Methadone maintenance treatment (MMT) is a major treatment regimen for opioid dependence. HCV infection may affect methadone metabolism but this has rarely been studied. In our current study, we aimed to test the hypothesis that HCV may influence the methadone dosage and its plasma metabolite concentrations in a MMT cohort from Taiwan. METHODS A total of 366 MMT patients were recruited. The levels of plasma hepatitis B virus (HBV), HCV, human immunodeficiency virus (HIV) antibodies (Ab), liver aspartate aminotransferase (AST) and alanine aminotransferase (ALT), as well as methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) were measured along with the urine morphine concentration and amphetamine screening. RESULTS Of the 352 subjects in our cohort with HCV test records, 95% were found to be positive for plasma anti-HCV antibody. The liver functional parameters of AST (Wilcoxon Rank-Sum test, P = 0.02) and ALT (Wilcoxon Rank-Sum test, P = 0.04), the plasma methadone concentrations (Wilcoxon Rank-Sum test, P = 0.043) and the R-enantiomer of methadone concentrations (Wilcoxon Rank-Sum test, P = 0.032) were significantly higher in the HCV antibody-positive subjects than in the HCV antibody-negative patients, but not the S-EDDP/methadone dose ratio. The HCV levels correlated with the methadone dose (β= 14.65 and 14.13; P = 0.029 and 0.03) and the S-EDDP/methadone dose ratio (β= -0.41 and -0.40; P = 0.00084 and 0.002) in both univariate and multivariate regression analyses. CONCLUSIONS We conclude that HCV may influence the methadone dose and plasma S-EDDP/methadone dose ratio in MMT patients in this preliminary study.
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Affiliation(s)
- Shiow-Ling Wu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Center for Research and Diagnostics, Centers for Disease Control, Department of Health, Executive Yuan, Taipei, Taiwan
| | - Sheng-Chang Wang
- Center for Neuropsychiatric Research, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Hsiao-Hui Tsou
- Division of Biostatistics and Bioinformatics, Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Hsiang-Wei Kuo
- Center for Neuropsychiatric Research, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Ing-Kang Ho
- Center for Neuropsychiatric Research, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
- Center for Drug Abuse and Addiction, China Medical University Hospital, Taichung, Taiwan
- Graduate Institute of Clinical Medical Science, College of Medicine, China Medical University, Taichung, Taiwan
| | - Sheng-Wen Liu
- Center for Neuropsychiatric Research, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Ya-Ting Hsu
- Division of Biostatistics and Bioinformatics, Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Yao-Sheng Chang
- Center for Neuropsychiatric Research, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Yu-Li Liu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Center for Neuropsychiatric Research, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
- Graduate Institute of Drug Safety, China Medical University, Taichung, Taiwan
- Department of Psychiatry, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
- * E-mail:
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Pharmacogenetics of chronic pain and its treatment. Mediators Inflamm 2013; 2013:864319. [PMID: 23766564 PMCID: PMC3671679 DOI: 10.1155/2013/864319] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 04/12/2013] [Indexed: 12/20/2022] Open
Abstract
This paper reviews the impact of genetic variability of drug metabolizing enzymes, transporters, receptors, and pathways involved in chronic pain perception on the efficacy and safety of analgesics and other drugs used for chronic pain treatment. Several candidate genes have been identified in the literature, while there is usually only limited clinical evidence substantiating for the penetration of the testing for these candidate biomarkers into the clinical practice. Further, the pain-perception regulation and modulation are still not fully understood, and thus more complex knowledge of genetic and epigenetic background for analgesia will be needed prior to the clinical use of the candidate genetic biomarkers.
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Moody DE. Metabolic and toxicological considerations of the opioid replacement therapy and analgesic drugs: methadone and buprenorphine. Expert Opin Drug Metab Toxicol 2013; 9:675-97. [PMID: 23537174 DOI: 10.1517/17425255.2013.783567] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
INTRODUCTION Methadone and buprenorphine are maintenance replacement therapies for opioid dependence; they are also used for pain management. Methadone and buprenorphine (to a lesser extent) have seen sharp increases in mortality associated with their use. They have distinct routes of metabolism (mostly cytochrome P450 dependent), and distinct pharmacologic activity of metabolites. As such, metabolism may play a role in differences in their toxicity. AREAS COVERED This article reviews peer-reviewed literature obtained from PubMed searches and literature referenced within. The review considers first an overview of drug use and mortality over the past decade. It then provides extensive detail on the in vitro and in vivo human metabolism of methadone and buprenorphine. Using both human and experimental animal studies it then presents the pharmacodynamic activity of parent drug and metabolites at the mu-opioid receptor, as P-glycoprotein substrates and plasma/brain concentration ratios, and activity at the hERG K(+) channel. Lessons learned from drug interaction studies in humans are then examined in an attempt to bring together the combined information. EXPERT OPINION The use and misuse of these drugs contributes to the epidemic in opioid-associated mortalities. A better understanding of metabolism-, transport- and co-medication-induced changes will contribute to their safer use.
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Affiliation(s)
- David E Moody
- University of Utah College of Pharmacy, Department of Pharmacology and Toxicology, Salt Lake City, UT 84108, USA.
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Functional impact of ABCB1 variants on interactions between P-glycoprotein and methadone. PLoS One 2013; 8:e59419. [PMID: 23527191 PMCID: PMC3602015 DOI: 10.1371/journal.pone.0059419] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 02/14/2013] [Indexed: 12/20/2022] Open
Abstract
Methadone is a widely used substitution therapy for opioid addiction. Large inter-individual variability has been observed in methadone maintenance dosages and P-glycoprotein (P-gp) was considered to be one of the major contributors. To investigate the mechanism of P-gp’s interaction with methadone, as well as the effect of genetic variants on the interaction, Flp-In™-293 cells stably transfected with various genotypes of human P-gp were established in the present study. The RNA and protein expression levels of human P-gp were confirmed by real-time quantitative RT-PCR and western blot, respectively. Utilizing rhodamine 123 efflux assay and calcein-AM uptake study, methadone was demonstrated to be an inhibitor of wild-type human P-gp via non-competitive kinetic (IC50 = 2.17±0.10 µM), while the variant-type human P-gp, P-gp with 1236T-2677T-3435T genotype and P-gp with 1236T-2677A-3435T genotype, showed less inhibition potency (IC50 = 2.97±0.09 µM and 4.43±1.10 µM, respectively) via uncompetitive kinetics. Methadone also stimulated P-gp ATPase and inhibited verapamil-stimulated P-gp ATPase activity under therapeutic concentrations. These results may provide a possible explanation for higher methadone dosage requirements in patients carrying variant-type of P-gp and revealed the possible drug-drug interactions in patients who receive concomitant drugs which are also P-gp substrates.
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Pharmacokinetic-pharmacodynamic modeling of mood and withdrawal symptoms in relation to plasma concentrations of methadone in patients undergoing methadone maintenance treatment. J Clin Psychopharmacol 2012; 32:666-71. [PMID: 22926601 DOI: 10.1097/jcp.0b013e3182664ecd] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The aims of the present study were to characterize the relationship between plasma racemic methadone and its enantiomers' concentrations with respect to their pharmacodynamic effects and to investigate the influence of potential covariates on the pharmacodynamic parameters in patients on methadone maintenance treatment (MMT). Eighty-eight regular subjects at the Sheffield Care Trust Substance Misuse Services were studied. Samples of blood and urine were collected before the daily dose of methadone. Blood samples were taken up to 5 hours after dose. Total plasma concentrations of (RS)-methadone and total and unbound plasma concentrations of both enantiomers were measured by liquid chromatography-mass spectrometry. The Total Mood Disturbance Score (TMDS), the Objective Opioid Withdrawal Scale (OOWS), and the Subjective Opioid Withdrawal Scale (SOWS) were used as measures of mood and withdrawal. Population pharmacokinetic/pharmacodynamic analysis and subsequent multiple regression analysis were used to determine the factors influencing the pharmacodynamic effects of methadone. Significant decreases (P ≤ 0.04) were observed in the scores for the TMDS, SOWS, and OOWS for 5 hours after methadone dosage. The TMDS had returned to baseline by 10 hours after dose (P = 0.98), at which time the SOWS remained significantly below baseline (P = 0.001). Multiple regression analysis revealed that 33% of the overall variation in unbound (R)-methadone EC50 was explained by 3 variables, namely CYP3A activity (9%), age (16%), and sex (8%). Age also accounted for 8% and 9% of the variation in total (rac)- and (R)-methadone EC50. The present study has confirmed that the duration of mood change in the present study was shorter than the effect of methadone in stabilizing withdrawal symptoms. Thus, it is likely that a once-daily dose of methadone, albeit effective for preventing withdrawal, may not be sufficient to improve mood in some patients. Finally, it was established that CYP3A activity, years of dependent use, sex, and age are major determinants of methadone EC50 with respect to TMDS.
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Holm KMD, Linnet K. Chiral Analysis of Methadone and its Main Metabolite, EDDP, in Postmortem Brain and Blood by Automated SPE and Liquid Chromatography-Mass Spectrometry. J Anal Toxicol 2012; 36:487-96. [DOI: 10.1093/jat/bks057] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Brown SM, Campbell SD, Crafford A, Regina KJ, Holtzman MJ, Kharasch ED. P-glycoprotein is a major determinant of norbuprenorphine brain exposure and antinociception. J Pharmacol Exp Ther 2012; 343:53-61. [PMID: 22739506 DOI: 10.1124/jpet.112.193433] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Norbuprenorphine is a major metabolite of buprenorphine and potent agonist of μ, δ, and κ opioid receptors. Compared with buprenorphine, norbuprenorphine causes minimal antinociception but greater respiratory depression. It is unknown whether the limited antinociception is caused by low efficacy or limited brain exposure. Norbuprenorphine is an in vitro substrate of the efflux transporter P-glycoprotein (Mdr1), but the role of P-glycoprotein in norbuprenorphine transport in vivo is unknown. This investigation tested the hypothesis that limited norbuprenorphine antinociception results from P-glycoprotein-mediated efflux and limited brain access. Human P-glycoprotein-mediated transport in vitro of buprenorphine, norbuprenorphine, and their respective glucuronide conjugates was assessed by using transfected cells. P-glycoprotein-mediated norbuprenorphine transport and consequences in vivo were assessed by using mdr1a(+/+) and mdr1a(-/-) mice. Antinociception was determined by hot-water tail-flick assay, and respiratory effects were determined by unrestrained whole-body plethysmography. Brain and plasma norbuprenorphine and norbuprenorphine-3-glucuronide were quantified by mass spectrometry. In vitro, the net P-glycoprotein-mediated efflux ratio for norbuprenorphine was nine, indicating significant efflux. In contrast, the efflux ratio for buprenorphine and the two glucuronide conjugates was unity, indicating absent transport. The norbuprenorphine brain/plasma concentration ratio was significantly greater in mdr1a(-/-) than mdr1a(+/+) mice. The magnitude and duration of norbuprenorphine antinociception were significantly increased in mdr1a(-/-) compared with mdr1a(+/+) mice, whereas the reduction in respiratory rate was similar. Results show that norbuprenorphine is an in vitro and in vivo substrate of P-glycoprotein. P-glycoprotein-mediated efflux influences brain access and antinociceptive, but not the respiratory, effects of norbuprenorphine.
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Affiliation(s)
- Sarah M Brown
- Department of Pediatrics, Washington University in St. Louis, St. Louis, MO 63110, USA
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Kharasch ED, Whittington D, Ensign D, Hoffer C, Bedynek PS, Campbell S, Stubbert K, Crafford A, London A, Kim T. Mechanism of efavirenz influence on methadone pharmacokinetics and pharmacodynamics. Clin Pharmacol Ther 2012; 91:673-84. [PMID: 22398970 PMCID: PMC3600645 DOI: 10.1038/clpt.2011.276] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Mechanisms by which efavirenz diminishes methadone plasma concentrations are unknown. This investigation determined efavirenz influence on clinical methadone disposition and miosis, intravenous and oral alfentanil clearance (hepatic and intestinal cytochrome P450 3A4/5 (CYP3A4/5) activity), fexofenadine disposition (intestinal transporters activity), and efavirenz clearance and 8-hydroxylation (CYP2B6 activity), and human hepatocyte effects. Efavirenz induced systemic and oral alfentanil clearances two- to fivefold and induced efavirenz 8-hydroxylation. Efavirenz stereoselectively decreased methadone plasma concentrations 50-70%. Methadone systemic and oral clearances, hepatic clearance and extraction ratio, N-demethylation, and metabolite formation clearance were stereoselectively increased two- to threefold. Bioavailability decreased. Efavirenz shifted methadone concentration-miosis curves leftward and upward. Efavirenz induced hepatocyte CYP2B6 and CYP3A4 expression, activity, and methadone N-demethylation. Results show that efavirenz coinduced hepatic CYP2B6 and CYP3A4/5, coinduced hepatic and intestinal CYP3A4/5, and coinduced gastrointestinal CYP3A4/5 and efflux transporters. Methadone disposition was most consistent with efavirenz induction of hepatic CYP2B6-mediated methadone N-demethylation. Efavirenz may alter methadone pharmacodynamics.
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Affiliation(s)
- E D Kharasch
- Division of Clinical and Translational Research, Department of Anesthesiology, Washington University in St Louis, St Louis, Missouri, USA.
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LINARDI RL, STOKES AM, ANDREWS FM. The effect of P-Glycoprotein on methadone hydrochloride flux in equine intestinal mucosa. J Vet Pharmacol Ther 2012; 36:43-50. [DOI: 10.1111/j.1365-2885.2012.01390.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Linardi RL, Stokes AM, Keowen ML, Barker SA, Hosgood GL, Short CR. Bioavailability and pharmacokinetics of oral and injectable formulations of methadone after intravenous, oral, and intragastric administration in horses. Am J Vet Res 2012; 73:290-5. [DOI: 10.2460/ajvr.73.2.290] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Kukanich B, Kukanich KS, Rodriguez JR. The effects of concurrent administration of cytochrome P-450 inhibitors on the pharmacokinetics of oral methadone in healthy dogs. Vet Anaesth Analg 2011; 38:224-30. [PMID: 21492388 DOI: 10.1111/j.1467-2995.2011.00602.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The objective was to examine the effects of inhibiting cytochrome P450 (CYP) on the pharmacokinetics of oral methadone in dogs. STUDY DESIGN Prospective non-randomized experimental trial. ANIMALS Six healthy Greyhounds (three male and three female). METHODS The study was divided into two phases. Oral methadone (mean = 2.1 mg kg(-1) PO) was administered as whole tablets in Phase 1. In Phase 2 oral methadone (2.1 mg kg(-1) PO) was administered concurrently with ketoconazole (13.0 mg kg(-1) PO q 24 hours), chloramphenicol (48.7 mg kg(-1) PO q 12 hours), fluoxetine (1.3 mg kg(-1) PO q 24 hours), and trimethoprim (6.5 mg kg(-1) PO q 24 hours). Blood was obtained for analysis of methadone plasma concentrations by liquid chromatography with mass spectrometry. The maximum plasma concentration (C(max)), time to C(max) (T(max)), and the area under the curve from time 0 to the last measurable time point above the limit of quantification of the analytical assay (AUC(0-LAST)) were compared statistically. RESULTS The C(max) of methadone was significantly different (p=0.016) for Phase 1 (5.5 ng mL(-1)) and Phase 2 (171.9 ng mL(-1)). The AUC(0-LAST) was also significantly different (p=0.004) for Phase 1 (13.1 hour ng mL(-1)) and Phase 2 (3075.2 hour ng mL(-1)). CONCLUSION AND CLINICAL RELEVANCE Concurrent administration of CYP inhibitors with methadone significantly increased the area under the curve and plasma concentrations of methadone after oral administration to dogs. Further studies are needed assessing more clinically relevant combinations of methadone and CYP inhibitors.
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Affiliation(s)
- Butch Kukanich
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA.
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Ronaldson PT, Davis TP. Targeting blood-brain barrier changes during inflammatory pain: an opportunity for optimizing CNS drug delivery. Ther Deliv 2011; 2:1015-41. [PMID: 22468221 PMCID: PMC3313594 DOI: 10.4155/tde.11.67] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The blood-brain barrier (BBB) is the most significant obstacle to effective CNS drug delivery. It possesses structural and biochemical features (i.e., tight-junction protein complexes and, influx and efflux transporters) that restrict xenobiotic permeation. Pathophysiological stressors (i.e., peripheral inflammatory pain) can alter BBB tight junctions and transporters, which leads to drug-permeation changes. This is especially critical for opioids, which require precise CNS concentrations to be safe and effective analgesics. Recent studies have identified molecular targets (i.e., endogenous transporters and intracellular signaling systems) that can be exploited for optimization of CNS drug delivery. This article summarizes current knowledge in this area and emphasizes those targets that present the greatest opportunity for controlling drug permeation and/or drug transport across the BBB in an effort to achieve optimal CNS opioid delivery.
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Affiliation(s)
- Patrick T Ronaldson
- Department of Medical Pharmacology, College of Medicine, University of Arizona, 1501 N Campbell Avenue, PO Box 245050, Tucso, AZ, USA.
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Gillis NK, Zhu HJ, Markowitz JS. An in vitro evaluation of guanfacine as a substrate for P-glycoprotein. Neuropsychiatr Dis Treat 2011; 7:501-5. [PMID: 21931492 PMCID: PMC3173033 DOI: 10.2147/ndt.s24153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND With a US Food and Drug Administration-labeled indication to treat attention-deficit/hyperactivity disorder (ADHD), the nonstimulant guanfacine has become the preferred α(2)-agonist for ADHD treatment. However, significant interindividual variability has been observed in response to guanfacine. Consequently, hypotheses of a contributing interaction with the ubiquitously expressed drug transporter, P-glycoprotein (P-gp), have arisen. We performed an in vitro study to determine if guanfacine is indeed a substrate of P-gp. METHODS Intracellular accumulation of guanfacine was compared between P-gp expressing LLC-PK1/MDR1 cells and P-gp-negative LLC-PK1 cells to evaluate the potential interaction between P-gp and guanfacine. Cellular retention of guanfacine was analyzed using a high-performance liquid chromatographic-ultraviolet method. Rhodamine6G, a known P-gp substrate, was included in the study as a positive control. RESULTS At guanfacine concentrations of 50 μM and 5 μM, intracellular accumulation of guanfacine in LLC-PK1/MDR1 cells was, 35.9% ± 4.8% and 49.0% ± 28.3% respectively, of that in LLC-PK1 cells. In comparison, the concentration of rhodamine6G, the positive P-gp substrate, in LLC-PK1/MDR1 cells was only 5% of that in LLC-PK1 cells. CONCLUSION The results of the intracellular accumulation study suggest that guanfacine is, at best, a weak P-gp substrate. Therefore, it is unlikely that P-gp, or any genetic variants thereof, are a determining factor in the interindividual variability of response observed with guanfacine therapy.
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Affiliation(s)
- Nancy K Gillis
- Department of Pharmacotherapy and Translational Research, University of Florida, Gainesville, FL, USA
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