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Xie Y, Brynildsen JK, Windisch K, Blendy JA. Neural Network Connectivity Following Opioid Dependence is Altered by a Common Genetic Variant in the µ-Opioid Receptor, OPRM1 A118G. J Neurosci 2024; 44:e1492232023. [PMID: 38124015 PMCID: PMC10866092 DOI: 10.1523/jneurosci.1492-23.2023] [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: 08/24/2023] [Revised: 11/24/2023] [Accepted: 11/29/2023] [Indexed: 12/23/2023] Open
Abstract
Opioid use disorder is a chronic, relapsing disease associated with persistent changes in brain plasticity. A common single nucleotide polymorphism (SNP) in the µ-opioid receptor gene, OPRM1 A118G, is associated with altered vulnerability to opioid addiction. Reconfiguration of neuronal connectivity may explain dependence risk in individuals with this SNP. Mice with the equivalent Oprm1 variant, A112G, demonstrate sex-specific alterations in the rewarding properties of morphine and heroin. To determine whether this SNP influences network-level changes in neuronal activity, we compared FOS expression in male and female mice that were opioid-naive or opioid-dependent. Network analyses identified significant differences between the AA and GG Oprm1 genotypes. Based on several graph theory metrics, including small-world analysis and degree centrality, we show that GG females in the opioid-dependent state exhibit distinct patterns of connectivity compared to other groups of the same genotype. Using a network control theory approach, we identified key cortical brain regions that drive the transition between opioid-naive and opioid-dependent brain states; however, these regions are less influential in GG females leading to sixfold higher average minimum energy needed to transition from the acute to the dependent state. In addition, we found that the opioid-dependent brain state is significantly less stable in GG females compared to other groups. Collectively, our findings demonstrate sex- and genotype-specific modifications in local, mesoscale, and global properties of functional brain networks following opioid exposure and provide a framework for identifying genotype differences in specific brain regions that play a role in opioid dependence.
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Affiliation(s)
- Yihan Xie
- Department of Systems Pharmacology and Translational Therapeutics and Perelman School of Medicine, University of Pennsylvania, Philadelphia 19104, Pennsylvania
| | - Julia K Brynildsen
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia 19104, Pennsylvania
| | - Kyle Windisch
- Department of Systems Pharmacology and Translational Therapeutics and Perelman School of Medicine, University of Pennsylvania, Philadelphia 19104, Pennsylvania
| | - Julie A Blendy
- Department of Systems Pharmacology and Translational Therapeutics and Perelman School of Medicine, University of Pennsylvania, Philadelphia 19104, Pennsylvania
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2
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McDevitt DS, Wade QW, McKendrick GE, Nelsen J, Starostina M, Tran N, Blendy JA, Graziane NM. The Paraventricular Thalamic Nucleus and Its Projections in Regulating Reward and Context Associations. eNeuro 2024; 11:ENEURO.0524-23.2024. [PMID: 38351131 PMCID: PMC10883411 DOI: 10.1523/eneuro.0524-23.2024] [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: 12/11/2023] [Revised: 01/23/2024] [Accepted: 01/23/2024] [Indexed: 02/17/2024] Open
Abstract
The paraventricular thalamic nucleus (PVT) is a brain region that mediates aversive and reward-related behaviors as shown in animals exposed to fear conditioning, natural rewards, or drugs of abuse. However, it is unknown whether manipulations of the PVT, in the absence of external factors or stimuli (e.g., fear, natural rewards, or drugs of abuse), are sufficient to drive reward-related behaviors. Additionally, it is unknown whether drugs of abuse administered directly into the PVT are sufficient to drive reward-related behaviors. Here, using behavioral as well as pathway and cell-type specific approaches, we manipulate PVT activity as well as the PVT-to-nucleus accumbens shell (NAcSh) neurocircuit to explore reward phenotypes. First, we show that bath perfusion of morphine (10 µM) caused hyperpolarization of the resting membrane potential, increased rheobase, and decreased intrinsic membrane excitability in PVT neurons that project to the NAcSh. Additionally, we found that direct injections of morphine (50 ng) in the PVT of mice were sufficient to generate conditioned place preference (CPP) for the morphine-paired chamber. Mimicking the inhibitory effect of morphine, we employed a chemogenetic approach to inhibit PVT neurons that projected to the NAcSh and found that pairing the inhibition of these PVT neurons with a specific context evoked the acquisition of CPP. Lastly, using brain slice electrophysiology, we found that bath-perfused morphine (10 µM) significantly reduced PVT excitatory synaptic transmission on both dopamine D1 and D2 receptor-expressing medium spiny neurons in the NAcSh, but that inhibiting PVT afferents in the NAcSh was not sufficient to evoke CPP.
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Affiliation(s)
- Dillon S McDevitt
- Neuroscience Program, Penn State College of Medicine, Hershey, Pennsylvania 17033
| | - Quinn W Wade
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, Pennsylvania 17033
| | - Greer E McKendrick
- Neuroscience Program, Penn State College of Medicine, Hershey, Pennsylvania 17033
| | - Jacob Nelsen
- Doctor of Medicine Program, Penn State College of Medicine, Hershey, Pennsylvania 17033
| | - Mariya Starostina
- Doctor of Medicine Program, Penn State College of Medicine, Hershey, Pennsylvania 17033
| | - Nam Tran
- Doctor of Medicine Program, Penn State College of Medicine, Hershey, Pennsylvania 17033
| | - Julie A Blendy
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Nicholas M Graziane
- Departments of Anesthesiology and Perioperative Medicine and Pharmacology, Penn State College of Medicine, Hershey, Pennsylvania 17033
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3
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Duffy EP, Bachtell RK, Ehringer MA. Opioid trail: Tracking contributions to opioid use disorder from host genetics to the gut microbiome. Neurosci Biobehav Rev 2024; 156:105487. [PMID: 38040073 PMCID: PMC10836641 DOI: 10.1016/j.neubiorev.2023.105487] [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: 08/29/2023] [Revised: 11/22/2023] [Accepted: 11/27/2023] [Indexed: 12/03/2023]
Abstract
Opioid use disorder (OUD) is a worldwide public health crisis with few effective treatment options. Traditional genetics and neuroscience approaches have provided knowledge about biological mechanisms that contribute to OUD-related phenotypes, but the complexity and magnitude of effects in the brain and body remain poorly understood. The gut-brain axis has emerged as a promising target for future therapeutics for several psychiatric conditions, so characterizing the relationship between host genetics and the gut microbiome in the context of OUD will be essential for development of novel treatments. In this review, we describe evidence that interactions between host genetics, the gut microbiome, and immune signaling likely play a key role in mediating opioid-related phenotypes. Studies in humans and model organisms consistently demonstrated that genetic background is a major determinant of gut microbiome composition. Furthermore, the gut microbiome is susceptible to environmental influences such as opioid exposure. Additional work focused on gene by microbiome interactions will be necessary to gain improved understanding of their effects on OUD-related behaviors.
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Affiliation(s)
- Eamonn P Duffy
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA; Institute for Behavioral Genetics, University of Colorado Boulder, Boulder, CO, USA.
| | - Ryan K Bachtell
- Institute for Behavioral Genetics, University of Colorado Boulder, Boulder, CO, USA; Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, CO, USA
| | - Marissa A Ehringer
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA; Institute for Behavioral Genetics, University of Colorado Boulder, Boulder, CO, USA
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4
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Tanaka R, Sato J, Ishikawa H, Sato T, Shino M, Ohde Y, Sato T, Mori K, Notsu A, Ohnami S, Mizuguchi M, Nagashima T, Yamaguchi K. Influence of genetic variants of opioid-related genes on opioid-induced adverse effects in patients with lung cancer: A STROBE-compliant observational study. Medicine (Baltimore) 2021; 100:e27565. [PMID: 34871222 PMCID: PMC8568420 DOI: 10.1097/md.0000000000027565] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 10/02/2021] [Indexed: 01/05/2023] Open
Abstract
Despite the dramatic advancement of cancer chemotherapy and immunotherapy, the insufficient progress has been made in basic or translational research on personalization of opioid therapy. Predicting the effectiveness of opioid analgesic therapy and the risk of adverse effects prior to therapy are expected to enable safer and more appropriate opioid therapy for cancer patients. In this study, we compared the incidence of opioid-induced adverse effects between patients with different variants of the genes related to responsiveness to opioid analgesics.Participants were 88 patients with lung cancer who provided general consent for exome sequencing and were treated with morphine or oxycodone at Shizuoka Cancer Center Hospital between April 2014 and August 2018. Incidence rates for 6 adverse effects of opioid therapy (somnolence, nausea, constipation, delirium, urinary retention, and pruritus) were determined and the influence of single nucleotide polymorphisms in coding regions of the opioid μ receptor 1 (OPRM1) (rs1799971), opioid δ receptor 1 (rs2234918), opioid κ receptor 1 (rs1051660), catechol-O-methyltransferase (COMT) (rs4680), dopamine receptor D2 (rs6275), adenosine triphosphate binding cassette B1 (rs1045642), G-protein regulated inward rectifier potassium channel 2 (rs2070995), and fatty acid amide hydrolase (rs324420) genes on those adverse effects were analyzed.Analysis of OPRM1 gene variant status (Asn133Asp A > G) showed that G/G homozygotes were at significantly lower risk of somnolence compared with A allele carriers (0% vs 28.4%; Fisher exact test, P = .005; OR, 0; 95% CI, 0-0.6), and analysis of COMT gene variant status (Val158Met, G > A) showed that G/G homozygotes were at significantly higher risk of somnolence compared with A allele carriers (35.0% vs 10.4%; Fisher exact test, P = .008; OR, 4.5; 95% CI, 1.4-18.1). No relationship between variant status and adverse effects was found for the other genes.These findings demonstrate that OPRM1 and COMT gene variants influence the risk of somnolence as an adverse effect of opioid analgesic therapy.
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Affiliation(s)
- Rei Tanaka
- Department of Pharmacy, Shizuoka Cancer Center Hospital, Shizuoka, Japan
- Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba, Japan
| | - Junya Sato
- Department of Pharmacy, Shizuoka Cancer Center Hospital, Shizuoka, Japan
- Department of Pharmacy, International University of Health and Welfare Hospital, Tochigi, Japan
- Faculty of Pharmacy, International University of Health and Welfare, Tochigi, Japan
| | - Hiroshi Ishikawa
- Department of Pharmacy, Shizuoka Cancer Center Hospital, Shizuoka, Japan
| | - Tetsu Sato
- Department of Pharmacy, Shizuoka Cancer Center Hospital, Shizuoka, Japan
| | - Michihiro Shino
- Department of Pharmacy, Shizuoka Cancer Center Hospital, Shizuoka, Japan
| | - Yasuhisa Ohde
- Division of Thoracic Surgery, Shizuoka Cancer Center Hospital, Shizuoka, Japan
| | - Tetsumi Sato
- Division of Palliative Medicine, Shizuoka Cancer Center Hospital, Shizuoka, Japan
| | - Keita Mori
- Clinical Research Center, Shizuoka Cancer Center Hospital, Shizuoka, Japan
| | - Akifumi Notsu
- Clinical Research Center, Shizuoka Cancer Center Hospital, Shizuoka, Japan
| | - Sumiko Ohnami
- Cancer Diagnostics Research Division, Shizuoka Cancer Center Research Institute, Shizuoka, Japan
| | - Maki Mizuguchi
- Office of the Project HOPE, Shizuoka Cancer Center Hospital, Shizuoka, Japan
| | - Takeshi Nagashima
- Cancer Diagnostics Research Division, Shizuoka Cancer Center Research Institute, Shizuoka, Japan
- SRL Inc, Tokyo, Japan
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Reed B, Kreek MJ. Genetic Vulnerability to Opioid Addiction. Cold Spring Harb Perspect Med 2021; 11:cshperspect.a039735. [PMID: 32205416 DOI: 10.1101/cshperspect.a039735] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Opioid addiction, also referred to as opioid use disorder, continues to be a devastating problem throughout the world. Familial relation and twin studies have revealed opioid addiction, like other addictive diseases, to be profoundly influenced by genetics. Genetics studies of opioid addiction have affirmed the importance of genetics contributors in susceptibility to develop opioid addiction, and also have important implications on treatment for opioid addiction. But the complexity of the interactions of multiple genetic variants across diverse genes, as well as substantial differences in allelic frequencies across populations, thus far limits the predictive value of individual genetics variants.
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Affiliation(s)
- Brian Reed
- The Laboratory of the Biology of Addictive Diseases, The Rockefeller University, New York, New York 10065, USA
| | - Mary Jeanne Kreek
- The Laboratory of the Biology of Addictive Diseases, The Rockefeller University, New York, New York 10065, USA
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6
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Demery-Poulos C, Chambers JM. Genetic variation in alcoholism and opioid addiction susceptibility and treatment: a pharmacogenomic approach. AIMS MOLECULAR SCIENCE 2021. [DOI: 10.3934/molsci.2021016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
<abstract>
<p>Alcohol and opioid abuse have pervasive and detrimental consequences from the individual to societal level. The extent of genetic contribution to alcoholism has been studied for decades, yielding speculative and often inconsistent results since the previous discovery of two pharmacokinetic variants strongly protective against alcoholism. The neurobiology of addiction involves innumerate genes with combinatorial and epistatic interactions, creating a difficult landscape for concrete conclusions. In contrast, pharmacogenomic variation in the treatment of alcoholism yields more immediate clinical utility, while also emphasizing pathways crucial to the progression of addiction. An improved understanding of genetic predisposition to alcohol abuse has inherent significance for opioid addiction and treatment, as the two drugs induce the same reward pathway. This review outlines current knowledge, treatments, and research regarding genetic predisposition to alcoholism, focusing on pharmacodynamic variation within the dopaminergic system and shared implications for opioid abuse. Multifaceted and highly polygenic, the phenotype of addiction seems to grow more complex as new research extends the scope of its impact on the brain, body, and progeny.</p>
</abstract>
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7
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Scarnati MS, Boreland AJ, Joel M, Hart RP, Pang ZP. Differential sensitivity of human neurons carrying μ opioid receptor (MOR) N40D variants in response to ethanol. Alcohol 2020; 87:97-109. [PMID: 32561311 PMCID: PMC7958146 DOI: 10.1016/j.alcohol.2020.05.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/15/2020] [Accepted: 05/25/2020] [Indexed: 12/11/2022]
Abstract
The acute and chronic effects of alcohol on the brain and behavior are linked to alterations in inhibitory synaptic transmission. Alcohol's most consistent effect at the synaptic level is probably a facilitation of γ-aminobutyric acid (GABA) release, as seen from several rodent studies. The impact of alcohol on GABAergic neurotransmission in human neurons is unknown, due to a lack of a suitable experimental model. Human neurons can also be used to model effects of genetic variants linked with alcohol use disorders (AUDs). The A118G single nucleotide polymorphism (SNP rs1799971) of the OPRM1 gene encoding the N40D (D40 minor allele) mu-opioid receptor (MOR) variant has been linked with individuals who have an AUD. However, while N40D is clearly associated with other drugs of abuse, involvement with AUDs is controversial. In this study, we employed Ascl1-and Dlx2-induced inhibitory neuronal cells (AD-iNs) generated from human iPS cell lines carrying N40D variants, and investigated the impact of ethanol acutely and chronically on GABAergic synaptic transmission. We found that N40 AD-iNs display a stronger facilitation (versus D40) of spontaneous and miniature inhibitory postsynaptic current frequency in response to acute ethanol application. Quantitative immunocytochemistry of Synapsin 1+ synaptic puncta revealed a similar synapse number between N40 and D40 iNs, suggesting an ethanol modulation of presynaptic GABA release without affecting synapse density. Interestingly, D40 iNs exposed to chronic intermittent ethanol application caused a significant increase in mIPSC frequency, with only a modest enhancement observed in N40 iNs. These data suggest that the MOR genotype may confer differential sensitivity to synaptic output, which depends on ethanol exposure time and concentration for AD-iNs and may help explain alcohol dependence in individuals who carry the MOR D40 SNPs. Furthermore, this study supports the use of human neuronal cells carrying risk-associated genetic variants linked to disease, as in vitro models to assay the synaptic actions of alcohol on human neuronal cells.
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Affiliation(s)
- Matthew S Scarnati
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, 08901, USA; Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Andrew J Boreland
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, 08901, USA; Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Marisa Joel
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, 08901, USA; Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, 08854, USA
| | - Ronald P Hart
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, 08854, USA; Human Genetics Institute of New Jersey, Piscataway, NJ, 08854, USA
| | - Zhiping P Pang
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, 08901, USA; Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ, 08901, USA.
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8
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Addiction associated N40D mu-opioid receptor variant modulates synaptic function in human neurons. Mol Psychiatry 2020; 25:1406-1419. [PMID: 31481756 PMCID: PMC7051890 DOI: 10.1038/s41380-019-0507-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 06/07/2019] [Accepted: 07/09/2019] [Indexed: 02/06/2023]
Abstract
The OPRM1 A118G single nucleotide polymorphism (SNP rs1799971) gene variant encoding the N40D µ-opioid receptor (MOR) has been associated with dependence on opiates and other drugs of abuse but its mechanism is unknown. The frequency of G-allele carriers is ~40% in Asians, ~16% in Europeans, and ~3% in African-Americans. With opioid abuse-related deaths rising at unprecedented rates, understanding these mechanisms may provide a path to therapy. Here we generated homozygous N40D subject-specific induced inhibitory neuronal cells (iNs) from seven human-induced pluripotent stem (iPS) cell lines from subjects of European descent (both male and female) and probed the impact of N40D MOR regulation on synaptic transmission. We found that D40 iNs exhibit consistently stronger suppression (versus N40) of spontaneous inhibitory postsynaptic currents (sIPSCs) across multiple subjects. To mitigate the confounding effects of background genetic variation on neuronal function, the regulatory effects of MORs on synaptic transmission were recapitulated in two sets of independently engineered isogenic N40D iNs. In addition, we employed biochemical analysis and observed differential N-linked glycosylation of human MOR N40D. This study identifies neurophysiological and molecular differences between human MOR variants that may predict altered opioid responsivity and/or dependence in this subset of individuals.
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9
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Lemos Duarte M, Devi LA. Post-translational Modifications of Opioid Receptors. Trends Neurosci 2020; 43:417-432. [PMID: 32459993 PMCID: PMC7323054 DOI: 10.1016/j.tins.2020.03.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 03/26/2020] [Accepted: 03/26/2020] [Indexed: 12/13/2022]
Abstract
Post-translational modifications (PTMs) are key events in signal transduction since they affect protein function by regulating their abundance and/or activity. PTMs involve the covalent attachment of functional groups to specific amino acids. Since they tend to be generally reversible, PTMs serve as regulators of signal transduction pathways. G-protein-coupled receptors (GPCRs) are major signaling proteins that undergo multiple types of PTMs. In this Review, we focus on the opioid receptors, members of GPCR family A, and highlight recent advances in the field that have underscored the importance of PTMs in the functional regulation of these receptors. Since opioid receptor activity plays a central role in the development of tolerance and addiction to morphine and other drugs of abuse, understanding the molecular mechanisms regulating receptor activity is of fundamental importance.
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Affiliation(s)
- Mariana Lemos Duarte
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lakshmi A Devi
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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10
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Saad Z, Hibar D, Fedgchin M, Popova V, Furey ML, Singh JB, Kolb H, Drevets WC, Chen G. Effects of Mu-Opiate Receptor Gene Polymorphism rs1799971 (A118G) on the Antidepressant and Dissociation Responses in Esketamine Nasal Spray Clinical Trials. Int J Neuropsychopharmacol 2020; 23:549-558. [PMID: 32367114 PMCID: PMC7710914 DOI: 10.1093/ijnp/pyaa030] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 03/27/2020] [Accepted: 04/29/2020] [Indexed: 12/17/2022] Open
Abstract
Background At ketamine and esketamine doses at which antidepressant doses are achieved, these agents are relatively selective, noncompetitive, N-methyl-D-aspartate receptor antagonists. However, at substantially higher doses, ketamine has shown mu-opioid receptor (MOR–gene symbol: OPRM1) agonist effects. Preliminary clinical studies showed conflicting results on whether naltrexone, a MOR antagonist, blocks the antidepressant action of ketamine. We examined drug-induced or endogenous MOR involvement in the antidepressant and dissociative responses to esketamine by assessing the effects of a functional single nucleotide polymorphism rs1799971 (A118G) of OPRM1, which is known to alter MOR agonist-mediated responses. Methods Participants with treatment-resistant depression from 2 phase III, double-blind, controlled trials of esketamine (or placebo) nasal spray plus an oral antidepressant were genotyped for rs1799971. Participants received the experimental agents twice weekly for 4 weeks. Antidepressant responses were rated using the change in Montgomery–Åsberg Depression Rating Scale (MADRS) score on days 2 and 28 post-dose initiation, and dissociative side effects were assessed using the Clinician-Administered Dissociative-States Scale at 40 minutes post-dose on days 1 and 25. Results In the esketamine + antidepressant arm, no significant genotype effect of single nucleotide polymorphism rs1799971 (A118G) on MADRS score reductions was detected on either day 2 or 28. By contrast, in the antidepressant + placebo arm, there was a significant genotype effect on MADRS score reductions on day 2 and a nonsignificant trend on day 28 towards an improvement in depression symptoms in G-allele carriers. No significant genotype effects on dissociative responses were detected. Conclusions Variation in rs1799971 (A118G) did not affect the antidepressant response to esketamine + antidepressant. Antidepressant response to antidepressant + placebo was increased in G-allele carriers, compatible with previous reports that release of endorphins/enkephalins may play a role in mediating placebo effect. Trial Registration NCT02417064 and NCT02418585; www.clinicaltrials.gov
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Affiliation(s)
- Ziad Saad
- Janssen Research & Development, San Diego, California
| | | | | | | | - Maura L Furey
- Janssen Research & Development, San Diego, California
| | | | - Hartmuth Kolb
- Janssen Research & Development, San Diego, California
| | | | - Guang Chen
- Janssen Research & Development, San Diego, California
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Hansson AC, Gründer G, Hirth N, Noori HR, Spanagel R, Sommer WH. Dopamine and opioid systems adaptation in alcoholism revisited: Convergent evidence from positron emission tomography and postmortem studies. Neurosci Biobehav Rev 2019; 106:141-164. [DOI: 10.1016/j.neubiorev.2018.09.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 09/08/2018] [Accepted: 09/14/2018] [Indexed: 12/20/2022]
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12
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Kaye AD, Garcia AJ, Hall OM, Jeha GM, Cramer KD, Granier AL, Kallurkar A, Cornett EM, Urman RD. Update on the pharmacogenomics of pain management. PHARMACOGENOMICS & PERSONALIZED MEDICINE 2019; 12:125-143. [PMID: 31308726 PMCID: PMC6613192 DOI: 10.2147/pgpm.s179152] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 05/09/2019] [Indexed: 12/30/2022]
Abstract
Pharmacogenomics is the study of genetic variants that impact drug effects through changes in a drug’s pharmacokinetics and pharmacodynamics. Pharmacogenomics is being integrated into clinical pain management practice because variants in individual genes can be predictive of how a patient may respond to a drug treatment. Pain is subjective and is considered challenging to treat. Furthermore, pain patients do not respond to treatments in the same way, which makes it hard to issue a consistent treatment regimen for all pain conditions. Pharmacogenomics would bring consistency to the subjective nature of pain and could revolutionize the field of pain management by providing personalized medical care tailored to each patient based on their gene variants. Additionally, pharmacogenomics offers a solution to the opioid crisis by identifying potentially opioid-vulnerable patients who could be recommended a nonopioid treatment for their pain condition. The integration of pharmacogenomics into clinical practice creates better and safer healthcare practices for patients. In this article, we provide a comprehensive history of pharmacogenomics and pain management, and focus on up to date information on the pharmacogenomics of pain management, describing genes involved in pain, genes that may reduce or guard against pain and discuss specific pain management drugs and their genetic correlations.
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Affiliation(s)
- Alan David Kaye
- Department of Anesthesiology, LSU Health Sciences Center, New Orleans, LA, USA
| | - Andrew Jesse Garcia
- Department of Anesthesiology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - O Morgan Hall
- Department of Anesthesiology, Louisiana State University School of Medicine, New Orleans, LA, USA
| | - George M Jeha
- Department of Anesthesiology, LSU Health Sciences Center New Orleans, New Orleans, LA, USA
| | - Kelsey D Cramer
- Department of Anesthesiology, LSU Health Sciences Center New Orleans, New Orleans, LA, USA
| | - Amanda L Granier
- Department of Anesthesiology, LSU Health Sciences Center New Orleans, New Orleans, LA, USA
| | - Anusha Kallurkar
- Department of Anesthesiology, LSU Health Shreveport, Shreveport, LA, USA
| | - Elyse M Cornett
- Department of Anesthesiology, LSU Health Shreveport, Shreveport, LA, USA
| | - Richard D Urman
- Department of Anesthesiology, Perioperative and Pain Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston, MA, USA
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13
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Candidate gene analyses for acute pain and morphine analgesia after pediatric day surgery: African American versus European Caucasian ancestry and dose prediction limits. THE PHARMACOGENOMICS JOURNAL 2019; 19:570-581. [PMID: 30760877 PMCID: PMC6693985 DOI: 10.1038/s41397-019-0074-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Revised: 10/30/2018] [Accepted: 12/21/2018] [Indexed: 12/17/2022]
Abstract
Acute pain and opioid analgesia demonstrate inter-individual variability and polygenic influence. In 241 children of African American and 277 of European Caucasian ancestry, we sought to replicate select candidate gene associations with morphine dose and postoperative pain and then to estimate dose prediction limits. Twenty-seven single-nucleotide polymorphisms (SNPs) from nine genes (ABCB1, ARRB2, COMT, DRD2, KCNJ6, MC1R, OPRD1, OPRM1, and UGT2B7) met selection criteria and were analyzed along with TAOK3. Few associations replicated: morphine dose (mcg/kg) in African American children and ABCB1 rs1045642 (A allele, β = -9.30, 95% CI: -17.25 to -1.35, p = 0.02) and OPRM1 rs1799971 (G allele, β = 23.19, 95% CI: 3.27-43.11, p = 0.02); KCNJ6 rs2211843 and high pain in African American subjects (T allele, OR 2.08, 95% CI: 1.17-3.71, p = 0.01) and in congruent European Caucasian pain phenotypes; and COMT rs740603 for high pain in European Caucasian subjects (A allele, OR: 0.69, 95% CI: 0.48-0.99, p = 0.046). With age, body mass index, and physical status as covariates, simple top SNP candidate gene models could explain theoretical maximums of 24.2% (European Caucasian) and 14.6% (African American) of morphine dose variances.
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14
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Sachdeo BLY, Yu L, Giunta GM, Bello NT. Binge-Like Eating Is Not Influenced by the Murine Model of OPRM1 A118G Polymorphism. Front Psychol 2019; 10:246. [PMID: 30804861 PMCID: PMC6378308 DOI: 10.3389/fpsyg.2019.00246] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 01/25/2019] [Indexed: 12/23/2022] Open
Abstract
Impairments in opioid receptor signaling have been implicated in disordered eating. A functional variant of the OPRM1 gene is a guanine (G) substitution for adenine (A) at the 118 position of exon 1 (A118G). The influence of the A118G variant on binge eating behaviors and the effectiveness of pharmacotherapies used to treat binge eating have not been characterized. Mice were generated with A to G substitution at the 112 position on exon 1 to produce a murine equivalent of the human A118G variant. Homozygous female mice (AA or GG) were exposed to intermittent access to a highly palatable sweet-fat food with or without prior calorie deprivation to promote dietary-induced binge eating. There were no genotype-dependent differences in the dietary-induced binge eating. However, GG mice exposed to intermittent calorie restriction (Restrict) had higher body weights compared with GG mice exposed to intermittent sweet fat-food (Binge) and ad libitum feeding (Naive). Acute oral dosing of lisdexamfetamine (0.15, 0.5, and 1.5 mg/kg) or sibutramine (0.3, 1, and 3 mg/kg) did not produce genotype-dependent differences in binge-like eating. In addition, no genotype-dependent differences in binge-like eating were observed with chronic (14-day) dosing of lisdexamfetamine (1.5 mg/kg/day) or sibutramine (3 mg/kg/day). In the chronic dosing, body weights were higher in the GG Restrict compared with AA Restrict. Our findings suggest that the A112G polymorphism does not influence binge eating behaviors or pharmacotherapies for treating binge eating.
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Affiliation(s)
- Bryn L. Y. Sachdeo
- Nutritional Sciences Graduate Program, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
| | - Lei Yu
- Department of Genetics, School of Arts and Sciences, and Center of Alcohol Studies, Graduate School of Applied and Professional Psychology, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
| | - Gina M. Giunta
- Department of Animal Sciences, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
| | - Nicholas T. Bello
- Nutritional Sciences Graduate Program, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
- Department of Animal Sciences, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
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15
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Freet CS, Alexander DN, Imperio CG, Ruiz-Velasco V, Grigson PS. Heroin-induced suppression of saccharin intake in OPRM1 A118G mice. Brain Res Bull 2017; 138:73-79. [PMID: 28939474 DOI: 10.1016/j.brainresbull.2017.09.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 09/12/2017] [Accepted: 09/15/2017] [Indexed: 12/19/2022]
Abstract
The single nucleotide polymorphism of the μ-opioid receptor, OPRM1 A118G, has been associated with greater drug and alcohol use, increased sensitivity to pain, and reduced sensitivity to the antinociceptive effects of opiates. In the present studies, we employed a 'humanized' mouse model containing the wild-type (118AA) or variant (118GG) allele to examine behavior in a model of heroin-induced devaluation of an otherwise palatable saccharin cue when repeated saccharin-heroin pairings occurred every 24h (Experiment 1) or every 48h (Experiment 2). The results showed that, while both the 118AA and 118GG mice demonstrated robust avoidance of the heroin-paired saccharin cue following daily taste-drug pairings, only the 118AA mice suppressed intake of the heroin-paired saccharin cue when 48h elapsed between each taste-drug pairing. Humanized 118GG mice, then, defend their intake of the sweet cue despite saccharin-heroin pairings and this effect is illuminated by the use of spaced, rather than massed, trials. Given that this pattern of strain difference is not evident with saccharin-cocaine pairings (Freet et al., 2015), reduced avoidance of the heroin-paired saccharin cue by the 118GG mice may be due to an interaction between the opiate and the subjects' drive for the sweet or, alternatively, to differential downstream sensitivity to the aversive kappa mediated properties of the drug. These alternative hypotheses are addressed.
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Affiliation(s)
- Christopher S Freet
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, United States.
| | - Danielle N Alexander
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, United States
| | - Caesar G Imperio
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, United States
| | - Victor Ruiz-Velasco
- Department of Anesthesiology and Perioperative Medicine, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, United States
| | - Patricia S Grigson
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, United States
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16
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Sweeney CG, Rando JM, Panas HN, Miller GM, Platt DM, Vallender EJ. Convergent Balancing Selection on the Mu-Opioid Receptor in Primates. Mol Biol Evol 2017; 34:1629-1643. [PMID: 28333316 PMCID: PMC6279279 DOI: 10.1093/molbev/msx105] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The mu opioid receptor is involved in many natural processes including stress response, pleasure, and pain. Mutations in the gene also have been associated with opiate and alcohol addictions as well as with responsivity to medication targeting these disorders. Two common and mutually exclusive polymorphisms have been identified in humans, A118G (N40D), found commonly in non-African populations, and C17T (V6A), found almost exclusively in African populations. Although A118G has been studied extensively for associations and in functional assays, C17T is much less well understood. In addition to a parallel polymorphism previously identified in rhesus macaques (Macaca mulatta), C77G (P26R), resequencing in additional non-human primate species identifies further common variation: C140T (P47L) in cynomolgus macaques (Macaca fascicularis), G55C (D19H) in vervet monkeys (Chlorocebus aethiops sabeus), A111T (L37F) in marmosets (Callithrix jacchus), and C55T (P19S) in squirrel monkeys (Saimiri boliviensis peruviensis). Functional effects on downstream signaling are observed for each of these variants following treatment with the endogenous agonist β-endorphin and the exogenous agonists morphine, DAMGO ([d-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin), and fentanyl. In addition to demonstrating the importance of functional equivalency in reference to population variation for minority health, this also shows how common evolutionary pressures have produced similar phenotypes across species, suggesting a shared response to environmental needs and perhaps elucidating the mechanism by which these organism-environment interactions are mediated physiologically and molecularly. These studies set the stage for future investigations of shared functional polymorphisms across species as a new genetic tool for translational research.
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Affiliation(s)
- Carolyn G. Sweeney
- Division of Neuroscience, New England Primate Research Center, Harvard Medical School, Southborough, MA
| | - Juliette M. Rando
- Division of Neuroscience, New England Primate Research Center, Harvard Medical School, Southborough, MA
| | - Helen N. Panas
- Division of Neuroscience, New England Primate Research Center, Harvard Medical School, Southborough, MA
| | - Gregory M. Miller
- Division of Neuroscience, New England Primate Research Center, Harvard Medical School, Southborough, MA
| | - Donna M. Platt
- Division of Neuroscience, New England Primate Research Center, Harvard Medical School, Southborough, MA
| | - Eric J. Vallender
- Division of Neuroscience, New England Primate Research Center, Harvard Medical School, Southborough, MA
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17
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Browne CA, Erickson RL, Blendy JA, Lucki I. Genetic variation in the behavioral effects of buprenorphine in female mice derived from a murine model of the OPRM1 A118G polymorphism. Neuropharmacology 2017; 117:401-407. [PMID: 28188737 DOI: 10.1016/j.neuropharm.2017.02.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 02/05/2017] [Accepted: 02/06/2017] [Indexed: 10/20/2022]
Abstract
Pharmacogenetic studies have identified the non-synonymous single nucleotide polymorphism (A118G) in the human mu opioid receptor (MOR) gene (OPRM1) as a critical genetic variant capable of altering the efficacy of opioid therapeutics. To date few studies have explored the potential impact of the OPRM1 A118G polymorphism on the pharmacological effects of buprenorphine (BPN), a potent MOR partial agonist and kappa opioid receptor antagonist, which is approved by the FDA for the treatment of opioid addiction and chronic pain. The goal of these studies was to determine whether the MOR-mediated behavioral effects of BPN were altered in the Oprm1 A112G mouse model of the human OPRM1 A118G SNP. All studies were conducted in female, AA, AG and GG mice. BPN's maximal analgesic effect in the hot plate test was significantly blunted in AG and GG mice compared to wild type AA mice. Similarly, the BPN-induced reduction of latency to consume food in the novelty induced hypophagia test was blocked entirely in AG and GG mice compared to their AA littermates. In addition, GG mice exhibited marked reductions in psychostimulant hyperlocomotor activity compared to the AA group. In contrast, reduced immobility in the forced swim test, an effect of BPN mediated by kappa opioid receptors, was not affected by genotype. These studies demonstrate the ability of the Oprm1 A112G SNP to attenuate the analgesic, anxiolytic and hyperlocomotor effects of BPN. Overall, these data suggest that the OPRM1 A118G SNP will significantly impact the clinical efficacy of BPN in its therapeutic applications.
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Affiliation(s)
- Caroline A Browne
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, United States.
| | - Rebecca L Erickson
- Department of Pathobiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Julie A Blendy
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania, Philadelphia, PA, United States
| | - Irwin Lucki
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, United States; Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania, Philadelphia, PA, United States
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18
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Bernardi RE, Zohsel K, Hirth N, Treutlein J, Heilig M, Laucht M, Spanagel R, Sommer WH. A gene-by-sex interaction for nicotine reward: evidence from humanized mice and epidemiology. Transl Psychiatry 2016; 6:e861. [PMID: 27459726 PMCID: PMC5545715 DOI: 10.1038/tp.2016.132] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 04/19/2016] [Accepted: 04/24/2016] [Indexed: 02/03/2023] Open
Abstract
It has been proposed that vulnerability to nicotine addiction is moderated by variation at the μ-opioid receptor locus (OPRM1), but results from human studies vary and prospective studies based on genotype are lacking. We have developed a humanized mouse model of the most common functional OPRM1 polymorphism rs1799971_A>G (A118G). Here we use this model system together with a cohort of German youth to examine the role of the OPRM1 A118G variation on nicotine reward. Nicotine reinforcement was examined in the humanized mouse model using i.v. self-administration. Male (n=17) and female (n=26) mice homozygous either for the major human A allele (AA) or the minor G allele (GG) underwent eight daily 2 h sessions of nicotine self-administration. Furthermore, male (n=104) and female (n=118) subjects homozygous for the A allele or carrying the G allele from the Mannheim Study of Children at Risk were evaluated for pleasurable and unpleasant experiences during their initial smoking experience. A significant sex-by-genotype effect was observed for nicotine self-administration. Male 118GG mice demonstrated higher nicotine intake than male 118AA mice, suggesting increased nicotine reinforcement. In contrast, there was no genotype effect in female mice. Human male G allele carriers reported increased pleasurable effects from their first smoking experience, as compared to male homozygous A, female G and female homozygous A allele carriers. The 118G allele appears to confer greater sensitivity to nicotine reinforcement in males, but not females.
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Affiliation(s)
- R E Bernardi
- Institute of Psychopharmacology, Central
Institute of Mental Health, Medical Faculty Mannheim/Heidelberg
University, Mannheim, Germany
| | - K Zohsel
- Department of Child and Adolescent
Psychiatry, Central Institute of Mental Health, Medical Faculty
Mannheim/Heidelberg University, Mannheim,
Germany
| | - N Hirth
- Institute of Psychopharmacology, Central
Institute of Mental Health, Medical Faculty Mannheim/Heidelberg
University, Mannheim, Germany
| | - J Treutlein
- Genetic Epidemiology, Central Institute
of Mental Health, Medical Faculty Mannheim/Heidelberg University,
Mannheim, Germany
| | - M Heilig
- Center for Social and Affective
Neuroscience, Linköping University, Linköping,
Sweden
| | - M Laucht
- Department of Child and Adolescent
Psychiatry, Central Institute of Mental Health, Medical Faculty
Mannheim/Heidelberg University, Mannheim,
Germany
| | - R Spanagel
- Institute of Psychopharmacology, Central
Institute of Mental Health, Medical Faculty Mannheim/Heidelberg
University, Mannheim, Germany
| | - W H Sommer
- Institute of Psychopharmacology, Central
Institute of Mental Health, Medical Faculty Mannheim/Heidelberg
University, Mannheim, Germany,Addiction Medicine, Central Institute of
Mental Health, Medical Faculty Mannheim/Heidelberg University,
Mannheim, Germany,Institute of Psychopharmacology, Central Institute of Mental
Health, Medical Faculty Mannheim/Heidelberg University, Square
J5, Mannheim
68159, Germany; E-mail:
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19
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Abstract
Alcohol addiction is one of the most common and devastating diseases in the world. Given the tremendous heterogeneity of alcohol addicted individuals, it is unlikely that one medication will help nearly all patients. Thus, there is a clear need to develop predictors of response to existing medications. Naltrexone is a mu-opioid receptor antagonist which has been approved in the United States for treatment of alcohol addiction since 1994. It has limited efficacy, in part due to noncompliance, but many patients do not respond despite high levels of compliance. There are reports that a mis-sense single nucleotide polymorphism (rs179919 or A118G) in the mu-opioid receptor gene predicts a favorable response to naltrexone if an individual carries a 'G' allele. This chapter will review the evidence for this hypothesis. The data are promising that the 'G' allele predisposes to a beneficial naltrexone response among alcohol addicted persons, but additional research is needed to prove this hypothesis in prospective clinical trials.
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Affiliation(s)
- Wade Berrettini
- Center for Neurobiology and Behavior, Perelman School of Medicine, University of Pennsylvania, 125 S. 31st St., Philadelphia, PA 19104, USA.
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20
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Baber M, Bapat P, Nichol G, Koren G. The pharmacogenetics of opioid therapy in the management of postpartum pain: a systematic review. Pharmacogenomics 2015; 17:75-93. [PMID: 26652709 DOI: 10.2217/pgs.15.157] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIMS Opioids are commonly prescribed for postpartum pain. Yet, providing adequate pain relief, while ensuring that the mother and her breastfeeding infant are protected from adverse events can be challenging. The objective of this systematic review was to identify the role of opioid pharmacogenetics in analgesia and adverse events among patients being treated for postpartum pain, along with their breastfeeding infants. METHODS A comprehensive search of the literature was conducted in seven databases on June 3-4, 2015. Two reviewers independently screened studies for eligibility, extracted data and evaluated study quality using the Newcastle-Ottawa Scale. RESULTS Among the 2082 papers retrieved from the search, 17 were included in the review. These 17 papers consisted of various study designs, opioids, polymorphisms and patient outcomes. This systematic review reveals that CYP2D6, OPRM1 A118G, UGT2B7 C802T and ABCB1 G2677AT may contribute to postpartum analgesia or adverse events. CONCLUSION These findings may assist in personalizing care for patients receiving opioids during the postpartum period.
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Affiliation(s)
- Marta Baber
- Division of Clinical Pharmacology & Toxicology, Department of Pediatrics, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada.,Department of Pharmacology & Toxicology, Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Priya Bapat
- Division of Clinical Pharmacology & Toxicology, Department of Pediatrics, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada.,Department of Pharmacology & Toxicology, Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Gail Nichol
- Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College St, Toronto, Ontario, M5S 3M2, Canada
| | - Gideon Koren
- Department of Pharmacology & Toxicology, Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
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21
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Henderson-Redmond AN, Yuill MB, Lowe TE, Kline AM, Zee ML, Guindon J, Morgan DJ. Morphine-induced antinociception and reward in "humanized" mice expressing the mu opioid receptor A118G polymorphism. Brain Res Bull 2015; 123:5-12. [PMID: 26521067 DOI: 10.1016/j.brainresbull.2015.10.007] [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: 08/10/2015] [Revised: 09/25/2015] [Accepted: 10/14/2015] [Indexed: 12/17/2022]
Abstract
The rewarding and antinociceptive effects of opioids are mediated through the mu-opioid receptor. The A118G single nucleotide polymorphism in this receptor has been implicated in drug addiction and differences in pain response. Clinical and preclinical studies have found that the G allele is associated with increased heroin reward and self-administration, elevated post-operative pain, and reduced analgesic responsiveness to opioids. Male and female mice homozygous for the "humanized" 118AA or 118GG alleles were evaluated to test the hypothesis that 118GG mice are less sensitive to the rewarding and antinociceptive effects of morphine. We found that 118AA and 118GG mice of both genders developed conditioned place preference for morphine. All mice developed tolerance to the antinociceptive and hypothermic effects of morphine. However, morphine tolerance was not different between AA and GG mice. We also examined sensitivity to the antinociceptive and hypothermic effects of cumulative morphine doses. We found that 118GG mice show reduced hypothermic and antinociceptive responses on the hotplate for 10mg/kg morphine. Finally, we examined basal pain response and morphine-induced antinociception in the formalin test for inflammatory pain. We found no gender or genotype differences in either basal pain response or morphine-induced antinociception in the formalin test. Our data suggests that homozygous expression of the GG allele in mice blunts morphine-induced hypothermia and hotplate antinociception but does not alter morphine CPP, morphine tolerance, or basal inflammatory pain response.
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Affiliation(s)
- Angela N Henderson-Redmond
- Department of Anesthesiology, Penn State University College of Medicine, Hershey, PA 17033, United States
| | - Matthew B Yuill
- Department of Anesthesiology, Penn State University College of Medicine, Hershey, PA 17033, United States; Department of Pharmacology, Penn State University College of Medicine, Hershey, PA 17033, United States; Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA 17033, United States
| | - Tammy E Lowe
- Department of Anesthesiology, Penn State University College of Medicine, Hershey, PA 17033, United States; Benedict College, Columbia, South Carolina 29204, United States
| | - Aaron M Kline
- Department of Anesthesiology, Penn State University College of Medicine, Hershey, PA 17033, United States
| | - Michael L Zee
- Department of Anesthesiology, Penn State University College of Medicine, Hershey, PA 17033, United States
| | - Josée Guindon
- Department of Pharmacology and Neuroscience, Texas Tech University Health Science Center, Lubbock, TX 79430, United States.
| | - Daniel J Morgan
- Department of Anesthesiology, Penn State University College of Medicine, Hershey, PA 17033, United States; Department of Pharmacology, Penn State University College of Medicine, Hershey, PA 17033, United States; Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA 17033, United States.
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22
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Berrettini W. Opioid neuroscience for addiction medicine: From animal models to FDA approval for alcohol addiction. PROGRESS IN BRAIN RESEARCH 2015; 223:253-67. [PMID: 26806780 DOI: 10.1016/bs.pbr.2015.07.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Alcohol addiction is one of the most common and devastating diseases in the world. Given the tremendous heterogeneity of alcohol-addicted individuals, it is unlikely that one medication will help nearly all patients. Thus, there is a clear need to develop predictors of response to existing medications. Naltrexone is a mu opioid receptor antagonist which has been approved in the United States for treatment of alcohol addiction since 1994. It has limited efficacy, in part due to noncompliance, but many patients do not respond despite high levels of compliance. There are reports that a mis-sense single-nucleotide polymorphism (rs179919 or A118G) in the mu opioid receptor gene predicts a favorable response to naltrexone if an individual carries a "G" allele. This chapter will review the evidence for this hypothesis. The data suggest that the "G" allele has a complex role in alcohol addiction, increasing the rewarding valence of alcohol. Whether the G allele increases risk for alcoholism and whether it predisposes to a beneficial naltrexone response among alcohol-addicted persons must await additional research with large sample sizes of multiple ethnicities in prospective clinical trials.
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Affiliation(s)
- Wade Berrettini
- Karl E Rickles Professor of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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23
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Robinson JE, Vardy E, DiBerto JF, Chefer VI, White KL, Fish EW, Chen M, Gigante E, Krouse MC, Sun H, Thorsell A, Roth BL, Heilig M, Malanga CJ. Receptor Reserve Moderates Mesolimbic Responses to Opioids in a Humanized Mouse Model of the OPRM1 A118G Polymorphism. Neuropsychopharmacology 2015; 40:2614-22. [PMID: 25881115 PMCID: PMC4569952 DOI: 10.1038/npp.2015.109] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 03/11/2015] [Accepted: 03/12/2015] [Indexed: 11/09/2022]
Abstract
The OPRM1 A118G polymorphism is the most widely studied μ-opioid receptor (MOR) variant. Although its involvement in acute alcohol effects is well characterized, less is known about the extent to which it alters responses to opioids. Prior work has shown that both electrophysiological and analgesic responses to morphine but not to fentanyl are moderated by OPRM1 A118G variation, but the mechanism behind this dissociation is not known. Here we found that humanized mice carrying the 118GG allele (h/mOPRM1-118GG) were less sensitive than h/mOPRM1-118AA littermates to the rewarding effects of morphine and hydrocodone but not those of other opioids measured with intracranial self-stimulation. Reduced morphine reward in 118GG mice was associated with decreased dopamine release in the nucleus accumbens and reduced effects on GABA release in the ventral tegmental area that were not due to changes in drug potency or efficacy in vitro or receptor-binding affinity. Fewer MOR-binding sites were observed in h/mOPRM1-118GG mice, and pharmacological reduction of MOR availability unmasked genotypic differences in fentanyl sensitivity. These findings suggest that the OPRM1 A118G polymorphism decreases sensitivity to low-potency agonists by decreasing receptor reserve without significantly altering receptor function.
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Affiliation(s)
- J Elliott Robinson
- Department of Neurology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA,Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Eyal Vardy
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Jeffrey F DiBerto
- Department of Neurology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA,Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Vladimir I Chefer
- Intramural Research Program, National Institute on Drug Abuse (NIDA), Baltimore, MD, USA
| | - Kate L White
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Eric W Fish
- Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Meng Chen
- Department of Neurology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA,Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Eduardo Gigante
- Intramural Research Program, National Institute on Drug Abuse (NIDA), Baltimore, MD, USA
| | - Michael C Krouse
- Department of Neurology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Hui Sun
- Intramural Research Program, National Institute on Alcohol Abuse and Alcoholism (NIAAA), Bethesda, MD, USA
| | - Annika Thorsell
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Bryan L Roth
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA,NIMH Psychoactive Drug Screening Program (PDSP), University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Markus Heilig
- Intramural Research Program, National Institute on Alcohol Abuse and Alcoholism (NIAAA), Bethesda, MD, USA,Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - C J Malanga
- Department of Neurology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA,Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA,Department of Neurology, University of North Carolina School of Medicine, Physicians' Office Building, 170 Manning Drive, CB 7025, Chapel Hill, NC 27599-7025, USA, Tel: +1 919 966 1683, Fax: +1 919 843 4576, E-mail:
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24
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Knapman A, Santiago M, Connor M. Buprenorphine signalling is compromised at the N40D polymorphism of the human μ opioid receptor in vitro. Br J Pharmacol 2015; 171:4273-88. [PMID: 24846673 DOI: 10.1111/bph.12785] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 05/02/2014] [Accepted: 05/03/2014] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE There is significant variation in individual response to opioid drugs, which may result in inappropriate opioid therapy. Polymorphisms of the μ opioid receptor (MOP receptor) may contribute to individual variation in opioid response by affecting receptor function, and the effect may be ligand-specific. We sought to determine functional differences in MOP receptor signalling at several signalling pathways using a range of structurally distinct opioid ligands in cells expressing wild-type MOP receptors (MOPr-WT) and the commonly occurring MOP receptor variant, N40D. EXPERIMENTAL APPROACH MOPr-WT and MOPr-N40D were stably expressed in CHO cells and in AtT-20 cells. Assays of AC inhibition and ERK1/2 phosphorylation were performed on CHO cells, and assays of K activation were performed on AtT-20 cells. Signalling profiles for each ligand were compared between variants. KEY RESULTS Buprenorphine efficacy was reduced by over 50% at MOPr-N40D for AC inhibition and ERK1/2 phosphorylation. Buprenorphine potency was reduced threefold at MOPr-N40D for K channel activation. Pentazocine efficacy was reduced by 50% for G-protein-gated inwardly rectifying K channel activation at MOPr-N40D. No other differences were observed for any other ligands tested. CONCLUSIONS AND IMPLICATIONS The N40D variant is present in 10-50% of the population. Buprenorphine is a commonly prescribed opioid analgesic, and many individuals do not respond to buprenorphine therapy. This study demonstrates that buprenorphine signalling to several effectors via the N40D variant of MOP receptors is impaired, and this may have important consequences in a clinical setting for individuals carrying the N40D allele.
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Affiliation(s)
- Alisa Knapman
- Australian School of Advanced Medicine, Macquarie University, Sydney, NSW, Australia
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Bilbao A, Robinson JE, Heilig M, Malanga CJ, Spanagel R, Sommer WH, Thorsell A. A pharmacogenetic determinant of mu-opioid receptor antagonist effects on alcohol reward and consumption: evidence from humanized mice. Biol Psychiatry 2015; 77:850-8. [PMID: 25442002 DOI: 10.1016/j.biopsych.2014.08.021] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 08/08/2014] [Accepted: 08/08/2014] [Indexed: 02/04/2023]
Abstract
BACKGROUND It has been proposed that therapeutic responses to naltrexone in alcoholism are moderated by variation at the mu-opioid receptor gene locus (OPRM1). This remains controversial because human results vary and no prospectively genotyped studies have been reported. We generated humanized mice carrying the respective human OPRM1 A118G alleles. Here, we used this model system to examine the role of OPRM1 A118G variation for opioid antagonist effects on alcohol responses. METHODS Effects of naltrexone on alcohol reward were examined using intracranial self-stimulation. Effects of naltrexone or nalmefene on alcohol intake were examined in continuous access home cage two-bottle free-choice drinking and operant alcohol self-administration paradigms. RESULTS Alcohol lowered brain stimulation reward thresholds in 118GG mice in a manner characteristic of rewarding drugs, and this effect was blocked by naltrexone. Brain stimulation reward thresholds were unchanged by alcohol or naltrexone in 118AA mice. In the home cage, increased alcohol intake emerged in 118GG mice with increasing alcohol concentrations and was 33% higher at 17% alcohol. At this concentration, naltrexone selectively suppressed alcohol intake in 118GG animals to a level virtually identical to that of 118AA mice. No effect of naltrexone was found in the latter group. Similarly, both naltrexone and nalmefene were more effective in suppressing operant alcohol self-administration in 118GG mice. CONCLUSIONS In a model that allows close experimental control, OPRM1 A118G variation robustly moderates effects of opioid antagonism on alcohol reward and consumption. These findings strongly support a personalized medicine approach to alcoholism treatment that takes into account OPRM1 genotype.
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Affiliation(s)
- Ainhoa Bilbao
- Institute of Psychopharmacology, Central Institute of Mental Health, University of Heidelberg, Mannheim, Germany
| | - J Elliott Robinson
- Laboratory of Developmental Neuropharmacology, University of North Carolina School of Medicine, Department of Neurology, Chapel Hill, North Carolina
| | - Markus Heilig
- Laboratory of Clinical and Translational Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland; Department of Clinical and Experimental Medicine, Linköpings Universitet, Linköping, Sweden
| | - C J Malanga
- Laboratory of Developmental Neuropharmacology, University of North Carolina School of Medicine, Department of Neurology, Chapel Hill, North Carolina
| | - Rainer Spanagel
- Institute of Psychopharmacology, Central Institute of Mental Health, University of Heidelberg, Mannheim, Germany
| | - Wolfgang H Sommer
- Institute of Psychopharmacology, Central Institute of Mental Health, University of Heidelberg, Mannheim, Germany
| | - Annika Thorsell
- Department of Clinical and Experimental Medicine, Linköpings Universitet, Linköping, Sweden.
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Mague SD, Port RG, McMullen ME, Carlson GC, Turner JR. Mouse model of OPRM1 (A118G) polymorphism has altered hippocampal function. Neuropharmacology 2015; 97:426-35. [PMID: 25986698 DOI: 10.1016/j.neuropharm.2015.04.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 04/08/2015] [Accepted: 04/27/2015] [Indexed: 01/08/2023]
Abstract
A single nucleotide polymorphism (SNP) in the human μ-opioid receptor gene (OPRM1 A118G) has been widely studied for its association in a variety of drug addiction and pain sensitivity phenotypes; however, the extent of these adaptations and the mechanisms underlying these associations remain elusive. To clarify the functional mechanisms linking the OPRM1 A118G SNP to altered phenotypes, we used a mouse model possessing the equivalent nucleotide/amino acid substitution in the Oprm1 gene. In order to investigate the impact of this SNP on circuit function, we used voltage-sensitive dye imaging in hippocampal slices and in vivo electroencephalogram recordings of the hippocampus following MOPR activation. As the hippocampus contains excitatory pyramidal cells whose activity is highly regulated by a dense network of inhibitory neurons, it serves as an ideal structure to evaluate how putative receptor function abnormalities may influence circuit activity. We found that MOPR activation increased excitatory responses in wild-type animals, an effect that was significantly reduced in animals possessing the Oprm1 SNP. Furthermore, in order to assess the in vivo effects of this SNP during MOPR activation, EEG recordings of hippocampal activity following morphine administration corroborated a loss-of-function phenotype. In conclusion, as these mice have been shown to have similar MOPR expression in the hippocampus between genotypes, these data suggest that the MOPR A118G SNP results in a loss of receptor function.
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Affiliation(s)
- Stephen D Mague
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Russell G Port
- Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Michael E McMullen
- Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Greg C Carlson
- Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Jill R Turner
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29036, USA.
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Roche DJ, Ray LA. Subjective response as a consideration in the pharmacogenetics of alcoholism treatment. Pharmacogenomics 2015; 16:721-36. [PMID: 25950242 DOI: 10.2217/pgs.14.143] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Currently available pharmacological treatments for alcoholism have modest efficacy and high individual variability in treatment outcomes, both of which have been partially attributed to genetic factors. One path to reducing the variability and improving the efficacy associated with these pharmacotherapies may be to identify overlapping genetic contributions to individual differences in both subjective responses to alcohol and alcoholism pharmacotherapy outcomes. As acute subjective response to alcohol is highly predictive of future alcohol related problems, identifying such shared genetic mechanisms may inform the development of personalized treatments that can effectively target converging pathophysiological mechanisms that convey risk for alcoholism. The focus of this review is to revisit the association between subjective response to alcohol and the etiology of alcoholism while also describing genetic contributions to this relationship, discuss potential pharmacogenetic approaches to target subjective response to alcohol in order to improve the treatment of alcoholism and examine conceptual and methodological issues associated with these topics, and outline future approaches to overcome these challenges.
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Affiliation(s)
- Daniel Jo Roche
- 1Department of Psychology, University of California, 1285 Franz Hall, Box 951563, Los Angeles, CA 90095-1563, USA
| | - Lara A Ray
- 1Department of Psychology, University of California, 1285 Franz Hall, Box 951563, Los Angeles, CA 90095-1563, USA
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Baber M, Chaudhry S, Kelly L, Ross C, Carleton B, Berger H, Koren G. The pharmacogenetics of codeine pain relief in the postpartum period. THE PHARMACOGENOMICS JOURNAL 2015; 15:430-5. [DOI: 10.1038/tpj.2015.3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/16/2014] [Accepted: 12/02/2014] [Indexed: 11/10/2022]
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Freet CS, Ballard SM, Alexander DN, Cox TA, Imperio CG, Anosike N, Carter AB, Mahmoud S, Ruiz-Velasco V, Grigson PS. Cocaine-induced suppression of saccharin intake and morphine modulation of Ca²⁺ channel currents in sensory neurons of OPRM1 A118G mice. Physiol Behav 2014; 139:216-23. [PMID: 25449401 DOI: 10.1016/j.physbeh.2014.11.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 11/11/2014] [Accepted: 11/12/2014] [Indexed: 01/09/2023]
Abstract
Several studies have shown that human carriers of the single nucleotide polymorphism of the μ-opioid receptor, OPRM1 A118G, exhibit greater drug and alcohol use, increased sensitivity to pain, and reduced sensitivity to the antinociceptive effects of opiates. In the present study, we employed a 'humanized' mouse model containing the wild-type (118AA) or variant (118GG) allele to examine behavior in our model of drug-induced suppression of a natural reward cue and to compare the morphine pharmacological profile in acutely isolated sensory neurons. Compared with 118AA mice, our results demonstrate that homozygous 118GG mice exhibit greater avoidance of the cocaine-paired saccharin cue, a behavior linked to an aversive withdrawal-like state. Electrophysiological recordings confirmed the reduced modulation of Ca(2+) channels by morphine in trigeminal ganglion (TG) neurons from 118GG mice compared to the 118AA control cells. However, repeated cocaine exposure in 118GG mice led to a leftward shift of the morphine concentration-response relationship when compared with 118GG control mice, while a rightward shift was observed in 118AA mice. These results suggest that cocaine exposure of mice carrying the 118G allele leads to a heightened sensitivity of the reward system and a blunted modulation of Ca(2+) channels by morphine in sensory neurons.
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Affiliation(s)
- Christopher S Freet
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA.
| | - Sarah M Ballard
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Danielle N Alexander
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Taylor A Cox
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Caesar G Imperio
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Nnaemeka Anosike
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Alyssa B Carter
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Saifeldin Mahmoud
- Department of Anesthesiology, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Victor Ruiz-Velasco
- Department of Anesthesiology, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Patricia S Grigson
- Department of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
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Abstract
Abstract
Background:
Although a number of studies have investigated the association of the OPRM1 A118G polymorphism with pain response, a consensus has not yet been reached.
Methods:
The authors searched PubMed, EMBASE, and the Cochrane Library to identify gene-association studies that explored the impact of the OPRM1 A118G polymorphism on postoperative opioid requirements through July 2013. Two evaluators independently reviewed and selected articles on the basis of prespecified selection criteria. The authors primarily investigated the standardized mean difference (SMD) of required amounts of opioids between AA homozygotes and G-allele carriers. The authors also performed subgroup analyses for race, opioid use, and type of surgery. Potential bias was assessed using the Egger’s test with a trim and fill procedure.
Results:
Three hundred forty-six articles were retrieved from databases, and 18 studies involving 4,607 participants were included in the final analyses. In a random-effect meta-analysis, G-allele carriers required a higher mean opioid dose than AA homozygotes (SMD, −0.18; P = 0.003). Although there was no evidence of publication bias, heterogeneity was present among studies (I2 = 66.8%). In the subgroup meta-analyses, significance remained robust in Asian patients (SMD, −0.21; P = 0.001), morphine users (SMD, −0.29; P <0.001), and patients who received surgery for a viscus (SMD, −0.20; P = 0.008).
Conclusions:
The OPRM1 A118G polymorphism was associated with interindividual variability in postoperative response to opioids. In a subpopulation, identifying OPRM1 A118G polymorphism may provide valuable information regarding the individual analgesic doses that are required to achieve satisfactory pain control.
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Knapman A, Connor M. Cellular signalling of non-synonymous single-nucleotide polymorphisms of the human μ-opioid receptor (OPRM1). Br J Pharmacol 2014; 172:349-63. [PMID: 24527749 DOI: 10.1111/bph.12644] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Revised: 01/21/2014] [Accepted: 02/07/2014] [Indexed: 12/15/2022] Open
Abstract
UNLABELLED There is significant variability in individual responses to opioid drugs, which is likely to have a significant genetic component. A number of non-synonymous single-nucleotide polymorphisms (SNPs) in the coding regions of the μ-opioid receptor gene (OPRM1) have been postulated to contribute to this variability. Although many studies have investigated the clinical influences of these μ-opioid receptor variants, the outcomes are reported in the context of thousands of other genes and environmental factors, and we are no closer to being able to predict individual response to opioids based on genotype. Investigation of how μ-opioid receptor SNPs affect their expression, coupling to second messengers, desensitization and regulation is necessary to understand how subtle changes in receptor structure can impact individual responses to opioids. To date, the few functional studies that have investigated the consequences of SNPs on the signalling profile of the μ-opioid receptor in vitro have shown that the common N40D variant has altered functional responses to some opioids, while other, rarer, variants display altered signalling or agonist-dependent regulation. Here, we review the data available on the effects of μ-opioid receptor polymorphisms on receptor function, expression and regulation in vitro, and discuss the limitations of the studies to date. Whether or not μ-opioid receptor SNPs contribute to individual variability in opioid responses remains an open question, in large part because we have relatively little good data about how the amino acid changes affect μ-opioid receptor function. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- Alisa Knapman
- Australian School of Advanced Medicine, Macquarie University, Sydney, NSW, Australia
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Walter C, Doehring A, Oertel BG, Lötsch J. µ-opioid receptor gene variant OPRM1 118 A>G: a summary of its molecular and clinical consequences for pain. Pharmacogenomics 2014; 14:1915-25. [PMID: 24236490 DOI: 10.2217/pgs.13.187] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The human µ-opioid receptor variant 118 A>G (rs1799971) has become one of the most analyzed genetic variants in the pain field. At the molecular level, the variant reduces opioid receptor signaling efficiency and expression, the latter probably via a genetic-epigenetic interaction. In experimental settings, the variant was reproducibly associated with decreased effects of exogenous opioids. However, this translates into very small clinical effects (meta-analysis of 14 studies: Cohen's d = 0.096; p = 0.008), consisting of slightly higher opioid dosing requirements in peri- and post-operative settings. An effect can neither be maintained for chronic analgesic therapy nor for opioid side effects. It seems unlikely that further studies will reveal larger effect sizes and, therefore, further analyses appear unwarranted. Thus, due to its small effect size, the SNP is without major clinical relevance as a solitary variant, but should be regarded as a part of complex genotypes underlying pain and analgesia.
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Affiliation(s)
- Carmen Walter
- Institute of Clinical Pharmacology, Johann Wolfgang Goethe-University, Goethe-University Hospital, Theodor-Stern-Kai 7, D-60590 Frankfurt am Main, Germany
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Wang YJ, Huang P, Blendy JA, Liu-Chen LY. Brain region- and sex-specific alterations in DAMGO-stimulated [(35) S]GTPγS binding in mice with Oprm1 A112G. Addict Biol 2014; 19:354-61. [PMID: 22862850 DOI: 10.1111/j.1369-1600.2012.00484.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The A118G single nucleotide polymorphism (SNP) of the human μ-opioid receptor (MOPR) gene (OPRM1) was associated with heightened dopamine release by alcohol intake, better treatment outcome for nicotine and alcohol addiction, and reduced analgesic responses to morphine. A mouse model that possesses the equivalent substitution (A112G) in the mouse MOPR gene (OPRM1) was generated to delineate the mechanisms of the impact of the SNP. Mice homozygous for the G112 allele (G/G) displayed lower morphine-induced antinociception than mice homozygous for the A112 allele (A/A), similar to the results in humans. In this study, we examined whether A112G SNP affected MOPR-mediated G protein activation in the mouse model. We compared A/A and G/G mice in the MOPR-selective agonist [D-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO)-stimulated [(35) S]GTPγS binding in brain regions by autoradiography. When the data of males and females were combined, G/G mice exhibited lower DAMGO-stimulated [(35) S]GTPγS binding in the ventral tegmental area than A/A mice, in accord with the previously reported reduced morphine-induced hyperactivity and locomotor sensitization in G/G mice. In the nucleus accumbens (NAc) core, female G/G mice displayed lower DAMGO-stimulated [(35) S]GTPγS binding than female A/A mice, which is consistent with the previously reported deficiency in morphine-induced conditioned place preference in female G/G mice. In G/G mice, males showed higher DAMGO-stimulated [(35) S]GTPγS binding than females in the cingulate cortex, caudate putamen, NAc core, thalamus and amygdala. Thus, A112G SNP affects DAMGO-stimulated [(35) S]GTPγS binding in region- and sex-specific manners.
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Affiliation(s)
- Yu-Jun Wang
- Department of Pharmacology; Center for Substance Abuse Research; Temple University School of Medicine; Philadelphia PA USA
| | - Peng Huang
- Department of Pharmacology; Center for Substance Abuse Research; Temple University School of Medicine; Philadelphia PA USA
| | - Julie A. Blendy
- Department of Pharmacology; Perelman School of Medicine; University of Pennsylvania; Philadelphia PA USA
| | - Lee-Yuan Liu-Chen
- Department of Pharmacology; Center for Substance Abuse Research; Temple University School of Medicine; Philadelphia PA USA
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Abstract
Studies on genetic contributions to labor analgesia have essentially evaluated the μ-opioid receptor gene (OPRM1), with some evidence that p.118A/G of OPRM1 influences the response to neuraxial opioids. As for labor progress, the β2-adrenergic receptor gene (ADRB2) is associated with preterm labor and delivery, and impacts the course of labor. Taken together though, there is no evidence that pharmacogenetic testing is needed or beneficial in the context of obstetric anesthesia; however, realizing the influence of genetic variants on specific phenotypes provides the rationale for a more cautious interpretation of clinical studies that attempt to find a dose-regimen that fits all.
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Affiliation(s)
- Ruth Landau
- Department of Anesthesiology and Pain Medicine, University of Washington Medical Center, 1959 NE Pacific Street, Seattle, WA 98195-6540, USA.
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Abstract
Alcohol addiction is one of the most common and devastating diseases in the world. Given the tremendous heterogeneity of alcohol-addicted individuals, it is unlikely that one medication will help nearly all patients. Thus, there is a clear need to develop predictors of response to existing medications. Naltrexone is a μ-opioid receptor antagonist, which has been approved in the United States for treatment of alcohol addiction since 1994. It has limited efficacy, in part because of noncompliance, but many patients do not respond despite high levels of compliance. There are reports that a missense single nucleotide polymorphism (rs179919 or A118G) in the μ-opioid receptor gene predicts a favorable response to naltrexone if an individual carries a "G" allele. This work will review the evidence for this hypothesis. The data are promising that the "G" allele predisposes to a beneficial naltrexone response among alcohol-addicted persons, but additional research is needed to prove this hypothesis in prospective clinical trials.
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Affiliation(s)
- Wade Berrettini
- Center for Neurobiology and Behavior, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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Mura E, Govoni S, Racchi M, Carossa V, Ranzani GN, Allegri M, van Schaik RH. Consequences of the 118A>G polymorphism in the OPRM1 gene: translation from bench to bedside? J Pain Res 2013; 6:331-53. [PMID: 23658496 PMCID: PMC3645947 DOI: 10.2147/jpr.s42040] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The 118A>G single nucleotide polymorphism (SNP) in the μ-opioid receptor (OPRM1) gene has been the most described variant in pharmacogenetic studies regarding opioid drugs. Despite evidence for an altered biological function encoded by this variant, this knowledge is not yet utilized clinically. The aim of the present review was to collect and discuss the available information on the 118A>G SNP in the OPRM1 gene, at the molecular level and in its clinical manifestations. In vitro biochemical and molecular assays have shown that the variant receptor has higher binding affinity for β-endorphins, that it has altered signal transduction cascade, and that it has a lower expression compared with wild-type OPRM1. Studies using animal models for 118A>G have revealed a double effect of the variant receptor, with an apparent gain of function with respect to the response to endogenous opioids but a loss of function with exogenous administered opioid drugs. Although patients with this variant have shown a lower pain threshold and a higher drug consumption in order to achieve the analgesic effect, clinical experiences have demonstrated that patients carrying the variant allele are not affected by the increased opioid consumption in terms of side effects.
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Affiliation(s)
- Elisa Mura
- Department of Drug Sciences, Centre of Excellence in Applied Biology, University of Pavia, Pavia, Italy
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Deumens R, Steyaert A, Forget P, Schubert M, Lavand’homme P, Hermans E, De Kock M. Prevention of chronic postoperative pain: Cellular, molecular, and clinical insights for mechanism-based treatment approaches. Prog Neurobiol 2013; 104:1-37. [DOI: 10.1016/j.pneurobio.2013.01.002] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 01/15/2013] [Accepted: 01/31/2013] [Indexed: 01/13/2023]
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Ginosar Y, Birnbach DJ, Shirov TT, Arheart K, Caraco Y, Davidson EM. Duration of analgesia and pruritus following intrathecal fentanyl for labour analgesia: no significant effect of A118G μ-opioid receptor polymorphism, but a marked effect of ethnically distinct hospital populations. Br J Anaesth 2013; 111:433-44. [PMID: 23592691 DOI: 10.1093/bja/aet075] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Genetic polymorphism (A118G) in the μ-opioid receptor has been reported to affect systemic opioid analgesia. However, reported pharmacogenetic effects on spinal opioid analgesia, particularly in labour, have been equivocal. METHODS We prospectively assessed effects of the μ-opioid receptor A118G single nucleotide polymorphism (SNP) on analgesia after 20 μg of spinal fentanyl. We studied two ethnically distinct hospital populations (Miami and Jerusalem). Independent variables were A118G, ethnicity, and hospital. Primary outcome was time from spinal analgesia until analgesic request. Secondary outcomes were pain and pruritus, assessed at repeated intervals until analgesia request. RESULTS One hundred and twenty-five nulliparous parturients in early labour were analysed. The allelic frequency of A118G was 14.8% (14.4% in Miami; 15.5% in Jerusalem). Time to analgesia request (sd) in Miami was 122 (44) min and in Jerusalem was 87 (32) min, P<0.001; Hispanic 123 (46) min vs Jew/Arab 87 (32) min, P<0.001; Black 121 (41) min vs Jew/Arab 87 (32) min, P=0.015. There was no significant effect of A118G. Survival analysis showed Miami > Jerusalem, P<0.001; Hispanics and Black > Jew/Arab, P<0.001; no effect of A118G. Within hospital groups, A118G had no effect on time to analgesic request; within genomic groups there was a significant difference between hospitals. The time-course for pruritus exactly paralleled the time-course for analgesia and was affected by hospital (P=0.006) and by ethnic group (P=0.03), but not by A118G. CONCLUSIONS We found no significant effect for the A118G single nucleotide polymorphism (SNP) on analgesic duration after spinal fentanyl for labour. In contrast, ethnically distinct hospital population groups exerted a marked effect on the time-course of both analgesia and pruritus.
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Affiliation(s)
- Y Ginosar
- Department of Anesthesiology and Critical Care Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
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ZHANG FAN, LIAO QIN, LI LI, WANG SAIYING, HU RONG, TANG YONGZHONG, OUYANG WEN. The correlation between post-operative fentanyl requirements and μ-opioid receptor gene A118G polymorphism in patients undergoing radical gastrectomy. Exp Ther Med 2013; 5:1147-1152. [PMID: 23599738 PMCID: PMC3628804 DOI: 10.3892/etm.2013.955] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 01/30/2013] [Indexed: 11/25/2022] Open
Abstract
The aim of this study was to investigate the effect of the μ-opioid receptor gene (OPRM1) A118G polymorphism on the requirement for post-operative fentanyl analgesia in patients undergoing radical gastrectomy. One hundred and twenty-eight gastric cancer patients scheduled to undergo radical gastrectomy under general anesthesia were enrolled in the study. Post-operative, patient-controlled intravenous analgesia of fentanyl was provided for satisfactory analgesia until 48 h after surgery. OPRM1 A118G was screened by DNA sequence analysis of polymerase chain reaction (PCR)-amplified DNA. Differences in fentanyl consumption and adverse effects were compared among the different genotypes at 24 and 48 h after surgery. The ranges of fentanyl dose in the 128 patients at 24 and 48 h after surgery were 5.4-17.3 μg/kg and 12.4-29.9 μg/kg, respectively. Among these patients, there were 54 wild-type homozygotes (AA), 53 heterozygotes (AG) and 21 mutant homozygotes (GG). The frequency of the G allele was 0.371 in the OPRM1 polymorphism. There were no significant differences in fentanyl dose or adverse effects, including nausea, vomiting and dizziness, for the OPRM1 A118G polymorphism (P>0.05). The OPRM1 A118G polymorphism does not play a significant role in post-operative fentanyl analgesic dose or post-operative nausea, vomiting and dizziness in patients undergoing radical gastrectomy.
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Affiliation(s)
| | - QIN LIAO
- Correspondence to: Dr Qin Liao, Department of Anesthesiology, The Third Xiangya Hospital of Central South University, No. 138 Tongzipo Road, Changsha 410013, P.R. China, E-mail:
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Abstract
AIMS To evaluate the pharmacogenetic evidence relating to the use of opioid antagonists (in particular naltrexone) in treating patients with alcohol abuse problems. METHODS Narrative review of pre-clinical and clinical published research regarding genetic modulation of psychotropic effects produced by alcohol and the therapeutic effects of opioid antagonists. RESULTS Alcohol activates brain reward pathways, leading to positive reinforcement of alcohol seeking and consumption. Thus, the underlying biological mechanisms may be targets for treatment, particularly in the early stages of addiction development. Alcohol reward is in part mediated by endogenous opioids. A single-nucleotide polymorphism (SNP) within the OPRM1 gene, A118G, leading to an amino acid change (Asn40Asp) in the extracellular portion of the receptor, has been implicated in alcoholism as well as in drug addiction, pain sensitivity and stress response, and in animal and human studies relates to the alcohol-dependent phenotype as well as to the treatment response to the µ-opioid antagonist naltrexone. CONCLUSION The effect size reported in naltrexone clinical studies is often small, which may be due to heterogeneity among patients. Pharmacogenetic approaches may help guide us in the search for the appropriate treatment optimal for one patient's need.
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Affiliation(s)
- Annika Thorsell
- Department of Clinical and Experimental Medicine, Linköping University, SE-581 83 Linköping, Sweden.
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Daher M, Costa FMM, Neves FAR. Genotyping the Mu-Opioid Receptor A118G Polymorphism Using the Real-time Amplification Refractory Mutation System: Allele Frequency Distribution Among Brazilians. Pain Pract 2013; 13:614-20. [DOI: 10.1111/papr.12042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 01/22/2013] [Indexed: 02/06/2023]
Affiliation(s)
- Mauricio Daher
- Department of Anesthesiology, University Hospital of Brasilia, University of Brasilia, Brasilia, Brazil
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43
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Abstract
This paper is the thirty-fourth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2011 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration (Section 16); and immunological responses (Section 17).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
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Vuilleumier PH, Stamer UM, Landau R. Pharmacogenomic considerations in opioid analgesia. PHARMACOGENOMICS & PERSONALIZED MEDICINE 2012; 5:73-87. [PMID: 23226064 PMCID: PMC3513230 DOI: 10.2147/pgpm.s23422] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Indexed: 12/25/2022]
Abstract
Translating pharmacogenetics to clinical practice has been particularly challenging in the context of pain, due to the complexity of this multifaceted phenotype and the overall subjective nature of pain perception and response to analgesia. Overall, numerous genes involved with the pharmacokinetics and dynamics of opioids response are candidate genes in the context of opioid analgesia. The clinical relevance of CYP2D6 genotyping to predict analgesic outcomes is still relatively unknown; the two extremes in CYP2D6 genotype (ultrarapid and poor metabolism) seem to predict pain response and/or adverse effects. Overall, the level of evidence linking genetic variability (CYP2D6 and CYP3A4) to oxycodone response and phenotype (altered biotransformation of oxycodone into oxymorphone and overall clearance of oxycodone and oxymorphone) is strong; however, there has been no randomized clinical trial on the benefits of genetic testing prior to oxycodone therapy. On the other hand, predicting the analgesic response to morphine based on pharmacogenetic testing is more complex; though there was hope that simple genetic testing would allow tailoring morphine doses to provide optimal analgesia, this is unlikely to occur. A variety of polymorphisms clearly influence pain perception and behavior in response to pain. However, the response to analgesics also differs depending on the pain modality and the potential for repeated noxious stimuli, the opioid prescribed, and even its route of administration.
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Affiliation(s)
- Pascal H Vuilleumier
- Klinik für Anästhesiologie und Schmerztherapie, Inselspital Universität Bern, Switzerland
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45
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46
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A118G Mu Opioid Receptor polymorphism increases inhibitory effects on CaV2.2 channels. Neurosci Lett 2012; 523:190-4. [PMID: 22796651 DOI: 10.1016/j.neulet.2012.06.074] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Revised: 06/21/2012] [Accepted: 06/29/2012] [Indexed: 01/22/2023]
Abstract
Single nucleotide polymorphisms (SNPs) in the human OPRM1 gene result in common variants of Mu Opioid Receptors (hMORs). The A118G SNP occurs at high frequency in certain human populations and produces an aminoacidic substitution: N40D (hMOR-N to hMOR-D) at protein level. N40D is reported to alter pain thresholds and morphine efficacy. hMORs inhibit Ca(V)2.2 channels (N-type currents) at presynaptic nociceptor terminals in dorsal horn, thus reducing calcium influx, transmitter release, and transmission of noxious signals. Nociceptors express different splice isoforms of Ca(V)2.2. Isoforms distinguished by the presence of alternatively spliced exon e37a are of interest because channels containing e37a are particularly enriched in nociceptors. Recent studies showed that Ca(V)2.2e37a is more sensitive to inhibition by Mu Opioid Receptors than the ubiquitous splice variant Ca(V)2.2e37b. Here, we evaluate the effect of hMOR-N and hMOR-D on cloned Ca(V)2.2e37a channels expressed in mammalian cells. We observe that hMOR-D inhibits Ca(V)2.2e37a currents at agonist concentrations 4-fold lower than those needed to inhibit Ca(V)2.2e37a currents by the same degree via hMOR-N. We observe little difference in hMOR-D and hMOR-N inhibition of Ca(V)2.2e37b currents. Our study demonstrates that this common site of OPRM1 polymorphism affects the inhibitory actions of MORs on both major Ca(V)2.2 isoforms expressed in nociceptors.
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Abstract
A large segment of the population suffers from addiction to alcohol, smoking, or illicit drugs. Not only do substance abuse and addiction pose a threat to health, but the consequences of addiction also impose a social and economic burden on families, communities, and nations. Genome-wide linkage and association studies have been used for addiction research with varying degrees of success. The most well-established genetic factors associated with alcohol dependence are in the genes encoding alcohol dehydrogenase (ADH), which oxidizes alcohol to acetaldehyde, and aldehyde dehydrogenase (ALDH2), which oxidizes acetaldehyde to acetate. Recently emerging genetic studies have linked variants in the genes encoding the α3, α5, and β4 nicotinic acetylcholine receptor subunits to smoking risk. However, the influence of these well-established genetic variants accounts for only a small portion of the heritability of alcohol and nicotine addiction, and it is likely that there are both common and rare risk variants yet to be identified. Newly developed DNA sequencing technologies could potentially advance the detection of rare variants with a larger impact on addiction risk.
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Affiliation(s)
- Jen-Chyong Wang
- Department of Psychiatry, School of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA.
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48
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Heilig M, Goldman D, Berrettini W, O'Brien CP. Pharmacogenetic approaches to the treatment of alcohol addiction. Nat Rev Neurosci 2011; 12:670-84. [PMID: 22011682 PMCID: PMC3408029 DOI: 10.1038/nrn3110] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Addictive disorders are partly heritable, chronic, relapsing conditions that account for a tremendous disease burden. Currently available addiction pharmacotherapies are only moderately successful, continue to be viewed with considerable scepticism outside the scientific community and have not become widely adopted as treatments. More effective medical treatments are needed to transform addiction treatment and address currently unmet medical needs. Emerging evidence from alcoholism research suggests that no single advance can be expected to fundamentally change treatment outcomes. Rather, studies of opioid, corticotropin-releasing factor, GABA and serotonin systems suggest that incremental advances in treatment outcomes will result from an improved understanding of the genetic heterogeneity among patients with alcohol addiction, and the development of personalized treatments.
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Affiliation(s)
- Markus Heilig
- Laboratory of Clinical and Translational Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland 20892, USA. markus.heilig@mail. nih.gov
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