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Schreihofer DA, Dalwadi D, Kim S, Metzger D, Oppong-Gyebi A, Das-Earl P, Schetz JA. Treatment of Stroke at a Delayed Timepoint with a Repurposed Drug Targeting Sigma 1 Receptors. Transl Stroke Res 2023:10.1007/s12975-023-01193-x. [PMID: 37704905 DOI: 10.1007/s12975-023-01193-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 08/04/2023] [Accepted: 09/01/2023] [Indexed: 09/15/2023]
Abstract
Sigma 1 receptors are intracellular chaperone proteins that have been explored as a subacute treatment to enhance post-stroke recovery. We recently identified the antitussive oxeladin as a selective sigma 1 receptor agonist with the ability to stimulate the release of brain-derived neurotrophic factor from neurons in vitro. In this study, we hypothesized that oral oxeladin citrate would stimulate BDNF secretion and improve stroke outcomes when administered to male rats starting 48 h after transient middle cerebral artery occlusion. Oxeladin did not alter blood clotting and crossed the blood brain barrier within 30 min of oral administration. Rats underwent 90 min of transient middle cerebral artery occlusion. Forty-eight hours later rats began receiving daily oxeladin (135 mg/kg) for 11 days. Oxeladin significantly improved neurological function on days 3, 7, and 14 following MCAO. Infarct size was not altered by a single dose, but the final extent of infarct after 14 days was decreased. However, there was no significant reduction in astrogliosis or microgliosis compared to vehicle-treated control rats. In agreement with in vitro studies, oxeladin increased the amount of mature BDNF in the cerebral cortex 2, 6, and 24 h after single oral dose. However, the increase in BDNF did not result in increases in cellular proliferation in the subventricular zone or dentate gyrus when compared to vehicle-treated controls. These results suggest that oxeladin may reduce the extent of infarct expansion in the subacute phase of stroke, although this action does not appear to involve a reduction in inflammation or increased cell proliferation.
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Affiliation(s)
- Derek A Schreihofer
- Department of Pharmacology and Neuroscience, University of North Texas Helath Science Center, Fort Worth, Texas, 76107, USA.
| | | | - Seongcheol Kim
- Department of Cellular and Molecular Physiology, Loyola University Chicago Stritch School of Medicine, Maywood, IL, 60153, USA
| | - Daniel Metzger
- Department of Pharmacology and Neuroscience, University of North Texas Helath Science Center, Fort Worth, Texas, 76107, USA
| | - Anthony Oppong-Gyebi
- Department of Pharmacology and Neuroscience, University of North Texas Helath Science Center, Fort Worth, Texas, 76107, USA
- Cognizant Technology Solutions, 300 Frank W. Burr Blvd, Teaneck, NJ, 07666, USA
| | - Paromita Das-Earl
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, 76107, USA
| | - John A Schetz
- Department of Pharmacology and Neuroscience, University of North Texas Helath Science Center, Fort Worth, Texas, 76107, USA
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Ji J, Gao C, Wang Q, Jia X, Tian H, Wei Y, Liu Z, Wang Y, Guo L. The sigma-1 receptor-TAMM41 axis modulates neuroinflammation and attenuates memory impairment during the latent period of epileptogenesis. Animal Model Exp Med 2023. [PMID: 37852612 DOI: 10.1002/ame2.12341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 07/18/2023] [Indexed: 10/20/2023] Open
Abstract
BACKGROUND Therapy in the latent period is favorable for retarding the process of epileptogenesis. Recently, we have discovered that the activated sigma-1 receptor (Sig-1R) attenuates the hippocampus pathological injury and memory impairment in the latent period of epileptogenesis. But the molecular mechanism needs further investigation. METHODS PRE-084 was utilized as a research tool to highly selectively activate Sig-1R in epileptic mice. After the treatment of PRE-084, the pro-inflammatory cytokines, neuropathological traits, and the level of mitochondrial translocator assembly and maintenance 41 homolog (TAMM41) in the hippocampus were examined. The mode in which the Sig-1R interacts with TAMM41 was explored. The role of TAMM41 in the protecting effect of PRE-084 was established. RESULTS PRE-084 inhibited the growth of pro-inflammatory cytokines, reduced the formation of gliosis, alleviated neuronal damage in the hippocampus, and attenuated memory impairment in the latent period of epileptogenesis. The protein level of TAMM41 decreased in the hippocampi of epileptic mice and increased in the PRE-084-treated mice. The Sig-1R bound with TAMM41 directly, maintaining the stability of TAMM41. Knockdown of TAMM41 reversed the protective effect of PRE-084, and overexpression of TAMM41 exhibited a similar protective action to that of PRE-084. CONCLUSION We presented the concept of the "sigma-1 receptor-TAMM41 axis" and proposed that augmenting this axis can attenuate neuroinflammation and memory impairment in the process of epileptogenesis.
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Affiliation(s)
- Jianlun Ji
- Department of Pharmacy, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Ce Gao
- Department of Pharmacy, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Qinghua Wang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Xiaoxia Jia
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Hao Tian
- Agro-Products Processing Research Institute, Yunnan Academy of Agricultural Sciences, Kunming, China
| | - Yaqin Wei
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Zhidong Liu
- Department of Pharmacy, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Yun Wang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Lin Guo
- Department of Pharmacy, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
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Malar DS, Thitilertdecha P, Ruckvongacheep KS, Brimson S, Tencomnao T, Brimson JM. Targeting Sigma Receptors for the Treatment of Neurodegenerative and Neurodevelopmental Disorders. CNS Drugs 2023; 37:399-440. [PMID: 37166702 PMCID: PMC10173947 DOI: 10.1007/s40263-023-01007-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/18/2023] [Indexed: 05/12/2023]
Abstract
The sigma-1 receptor is a 223 amino acid-long protein with a recently identified structure. The sigma-2 receptor is a genetically unrelated protein with a similarly shaped binding pocket and acts to influence cellular activities similar to the sigma-1 receptor. Both proteins are highly expressed in neuronal tissues. As such, they have become targets for treating neurological diseases, including Alzheimer's disease (AD), Huntington's disease (HD), Parkinson's disease (PD), multiple sclerosis (MS), Rett syndrome (RS), developmental and epileptic encephalopathies (DEE), and motor neuron disease/amyotrophic lateral sclerosis (MND/ALS). In recent years, there have been many pre-clinical and clinical studies of sigma receptor (1 and 2) ligands for treating neurological disease. Drugs such as blarcamesine, dextromethorphan and pridopidine, which have sigma-1 receptor activity as part of their pharmacological profile, are effective in treating multiple aspects of several neurological diseases. Furthermore, several sigma-2 receptor ligands are under investigation, including CT1812, rivastigmine and SAS0132. This review aims to provide a current and up-to-date analysis of the current clinical and pre-clinical data of drugs with sigma receptor activities for treating neurological disease.
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Affiliation(s)
- Dicson S Malar
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand
| | - Premrutai Thitilertdecha
- Siriraj Research Group in Immunobiology and Therapeutic Sciences, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Kanokphorn S Ruckvongacheep
- Department of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Sirikalaya Brimson
- Department of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Tewin Tencomnao
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand
| | - James M Brimson
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand.
- Research, Innovation and International Affairs, Faculty of Allied Health Sciences, Chulalongkorn University, Room 409, ChulaPat-1 Building, 154 Rama 1 Road, Bangkok, 10330, Thailand.
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Vavers E, Zvejniece L, Dambrova M. Sigma-1 receptor and seizures. Pharmacol Res 2023; 191:106771. [PMID: 37068533 PMCID: PMC10176040 DOI: 10.1016/j.phrs.2023.106771] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 04/03/2023] [Accepted: 04/13/2023] [Indexed: 04/19/2023]
Abstract
Over the last decade, sigma-1 receptor (Sig1R) has been recognized as a valid target for the treatment of seizure disorders and seizure-related comorbidities. Clinical trials with Sig1R ligands are underway testing therapies for the treatment of drug-resistant seizures, developmental and epileptic encephalopathies, and photosensitive epilepsy. However, the direct molecular mechanism by which Sig1R modulates seizures and the balance between excitatory and inhibitory pathways has not been fully elucidated. This review article aims to summarize existing knowledge of Sig1R and its involvement in seizures by focusing on the evidence obtained from Sig1R knockout animals and the anti-seizure effects of Sig1R ligands. In addition, this review article includes a discussion of the advantages and disadvantages of the use of existing compounds and describes the challenges and future perspectives on the use of Sig1R as a target for the treatment of seizure disorders.
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Affiliation(s)
- Edijs Vavers
- Latvian Institute of Organic Synthesis, Laboratory of Pharmaceutical Pharmacology, Aizkraukles 21, LV-1006, Riga, Latvia; University of Tartu, Faculty of Science and Technology, Institute of Chemistry, Ravila 14a, 50411, Tartu, Estonia.
| | - Liga Zvejniece
- Latvian Institute of Organic Synthesis, Laboratory of Pharmaceutical Pharmacology, Aizkraukles 21, LV-1006, Riga, Latvia
| | - Maija Dambrova
- Latvian Institute of Organic Synthesis, Laboratory of Pharmaceutical Pharmacology, Aizkraukles 21, LV-1006, Riga, Latvia; Riga Stradiņš University, Faculty of Pharmacy, Konsula 21, LV-1007, Riga, Latvia
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Windhab LG, Gastberger S, Hulka LM, Baumgartner MR, Soyka M, Müller TJ, Seifritz E, Mutschler J. Dextromethorphan Abuse Among Opioid-Dependent Patients. Clin Neuropharmacol 2021; 43:127-133. [PMID: 32947422 DOI: 10.1097/wnf.0000000000000403] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Among opioid-dependent patients on maintenance therapy, concomitant drug abuse is a serious problem. Dextromethorphan, an over-the-counter antitussive agent that can be purchased without prescription, is a drug with a high potential for misuse, especially when consumed in high doses.The objective of this study was to investigate possible abuse of dextromethorphan among substituted opioid-dependent patients and comparison of subjective and objective findings.Due to its ability to increase serotonin levels, opioid-dependent patients may be particularly susceptible to dextromethorphan misuse. Dextromethorphan misuse may have side effects, including psychiatric symptoms and serotonin syndrome, and may induce assault, suicide, or homicide. METHODS A total of 104 opioid-dependent patients in maintenance treatment were included in this cross-sectional study conducted in the outpatient department of the Psychiatric Hospital, University of Zurich. Study participants were divided into 2 groups based on laboratory results: dextromethorphan abusers (n = 12) and nonabusers (n = 92). The objective use and concentrations of dextromethorphan was detected using 3-month hair toxicology analysis.Statistical analysis was performed by using χ test, Student t test, Mann-Whitney U test, and Barnard exact test. RESULTS Dextromethorphan was abused by 12 (11.5%) patients, 11 (91.7%) of whom did not report concomitant abuse of dextromethorphan but were identified through hair analysis. In general, there were significant differences among patients abusing dextromethorphan compared with nondextromethorphan consumers in terms of trauma due to sexual maltreatment/violence, multiple traumas, or harmful use of hallucinogenic drugs. CONCLUSIONS Further studies are necessary to examine dextromethorphan and its impact on patients with psychiatric comorbidities and psychiatric medication. According to literature, there is a significant drug interaction risk due to the impact of dextromethorphan misuse on serotonin syndrome and psychiatric symptoms.1-3 We recommend active inquiry into and testing for concomitant drug abuse among substituted opioid-dependent patients to reduce the risk of drug interactions and side effects in this especially vulnerable group of patients.
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Affiliation(s)
| | - Salome Gastberger
- Department of Psychiatry, Center for Addictive Disorders, Psychotherapy and Psychosomatics, Psychiatric Hospital
| | - Lea M Hulka
- Department of Psychiatry, Center for Addictive Disorders, Psychotherapy and Psychosomatics, Psychiatric Hospital
| | - Markus R Baumgartner
- Zurich Institute of Forensic Medicine, Center for Forensic Hair Analysis, University of Zurich, Zürich, Switzerland
| | | | | | - Erich Seifritz
- Psychiatric Hospital University of Munich, Munich, GermanyDepartment of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zürich, Switzerland
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Prasanth MI, Malar DS, Tencomnao T, Brimson JM. The emerging role of the sigma-1 receptor in autophagy: hand-in-hand targets for the treatment of Alzheimer's. Expert Opin Ther Targets 2021; 25:401-414. [PMID: 34110944 DOI: 10.1080/14728222.2021.1939681] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 06/03/2021] [Indexed: 01/18/2023]
Abstract
INTRODUCTION Autophagy is a cellular catabolic mechanism that helps clear damaged cellular components and is essential for normal cellular and tissue function. The sigma-1 receptor (σ-1R) is a chaperone protein involved in signal transduction, neurite outgrowth, and plasticity, improving memory, and neuroprotection. Recent evidence shows that σ-1R can promote autophagy. Autophagy activation by the σ-1Rs along with other neuroprotective effects makes it an interesting target for the treatment of Alzheimer's disease. AF710B, T-817 MA, and ANAVEX2-73 are some of the σ-1R agonists which have shown promising results and have entered clinical trials. These molecules have also been found to induce autophagy and show cytoprotective effects in cellular models. AREAS COVERED This review provides insight into the current understanding of σ-1R functions related to autophagy and their role in alleviating AD. EXPERT OPINION We propose a mechanism through which the activation of σ-1R and autophagy could alter amyloid precursor protein processing to inhibit amyloid-β production by reconstituting cholesterol and gangliosides in the lipid raft to offer neuroprotection against AD. Future AD treatment could involve the combined targeting of the σ-1R and autophagy activation. We suggest that future studies investigate the link between autophagy the σ-1R and AD.
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Affiliation(s)
- Mani Iyer Prasanth
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Dicson Sheeja Malar
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Tewin Tencomnao
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - James Michael Brimson
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
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Saavedra JS, Garrett PI, Honeycutt SC, Peterson AM, White JW, Hillhouse TM. Assessment of the rapid and sustained antidepressant-like effects of dextromethorphan in mice. Pharmacol Biochem Behav 2020; 197:173003. [DOI: 10.1016/j.pbb.2020.173003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/20/2020] [Accepted: 07/27/2020] [Indexed: 01/01/2023]
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Silva AR, Dinis-Oliveira RJ. Pharmacokinetics and pharmacodynamics of dextromethorphan: clinical and forensic aspects. Drug Metab Rev 2020; 52:258-282. [DOI: 10.1080/03602532.2020.1758712] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Ana Rita Silva
- Department of Public Health and Forensic Sciences, and Medical Education, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Ricardo Jorge Dinis-Oliveira
- Department of Public Health and Forensic Sciences, and Medical Education, Faculty of Medicine, University of Porto, Porto, Portugal
- Department of Sciences, IINFACTS – Institute of Research and Advanced Training in Health Sciences and Technologies, University Institute of Health Sciences (IUCS), CESPU, CRL, Gandra, Portugal
- Department of Biological Sciences, Faculty of Pharmacy, Laboratory of Toxicology, UCIBIO, REQUIMTE, University of Porto, Porto, Portugal
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Li YY, Chiu CC, Wang JJ, Chen YW, Hung CH. Dopamine enhancement of dextrorphan-induced skin antinociception in response to needle pinpricks in rats. Pharmacol Rep 2019; 71:732-737. [PMID: 31207435 DOI: 10.1016/j.pharep.2019.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 03/08/2019] [Accepted: 04/08/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND Dextrorphan with long-acting local anesthetic effects did not cause system toxicity as fast as bupivacaine, while catecholamines (i.e., epinephrine) with the vasoconstrictive characteristics enhanced the effects of local anesthetic drugs. The objective of the experiment was to examine the synergistic effect of local dopamine (a catecholamine) injection on cutaneous antinociception of dextrorphan. METHODS The panniculus reflex in response to skin stimulation with a needle was used as the primary endpoint when dextrorphan (1.50, 2.61, 5.46, 10.20 and 20.40 μmol) alone, dopamine (16.20, 32.40, 51.60, 60.00 and 81.60 μmol) alone, or dopamine + dextrorphan (a ratio of ED50vs. ED50) was injected subcutaneously on the rat's back. We used an isobolographic modelling approach to determine whether a synergistic effect would be observed. RESULTS We showed that dextrorphan, dopamine, or the mixture of dopamine and dextrorphan produced dose-related skin antinociception. The potency (ED50, 50% effective dose) for cutaneous antinociception was dextrorphan [6.02 (5.93-6.14) μmol] greater than dopamine [48.91 (48.80-49.06) μmol] (p < 0.01). The duration of nociceptive inhibition induced by dopamine was longer than that induced by dextrorphan (p < 0.01) based on their equipotent doses (ED25, ED50, and ED75). Enhancement and prolongation of skin antinociception occurred after co-administration of dopamine with dextrorphan. CONCLUSIONS When compared to dopamine, dextrorphan was more potent and had a shorter duration of skin nociceptive block. Dopamine produced a synergistic effect on dextrorphan-mediated antinociception, and prolonged dextrorphan's antinociceptive duration.
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Affiliation(s)
- Yu-Yu Li
- Department of Anesthesiology, Chi-Mei Medical Center (Chiali branch), Tainan, Taiwan
| | - Chong-Chi Chiu
- Department of General Surgery, Chi-Mei Medical Center, Tainan and Liouying, Taiwan; Department of Electrical Engineering, Southern Taiwan University of Science and Technology, Tainan, Taiwan
| | - Jhi-Joung Wang
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan; Allied AI Biomed Center, Southern Taiwan University of Science and Technology, Tainan, Taiwan
| | - Yu-Wen Chen
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan; Department of Physical Therapy, College of Health Care, China Medical University, Taichung, Taiwan
| | - Ching-Hsia Hung
- Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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Valent DJ, Wong WT, Chew EY, Cukras CA. Oral Dextromethorphan for the Treatment of Diabetic Macular Edema: Results From a Phase I/II Clinical Study. Transl Vis Sci Technol 2018; 7:24. [PMID: 30584490 PMCID: PMC6300336 DOI: 10.1167/tvst.7.6.24] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 08/18/2018] [Indexed: 12/14/2022] Open
Abstract
Purpose The activation of microglia, the primary innate immune cell resident in the retina, produces inflammatory mediators, which underlie changes in diabetic retinopathy including increased vascular permeability. This study evaluates the safety and efficacy of dextromethorphan, a drug capable of inhibiting microglial activation, in the treatment of diabetic macular edema (DME). Methods A single-center, prospective, open-label phase I/II clinical trial enrolled five participants with macular involving DME who received oral dextromethorphan 60 mg twice daily for 6 months as monotherapy. Main outcome variables included central retinal subfield thickness (CST), best-corrected visual acuity (BCVA), macula sensitivity, and late leakage on fluorescein angiogram (FA). Results The study drug was well tolerated. At the primary end point of 6 months, mean CST decreased by −6.3% ± 6.8% and BCVA increased by +0.6 ± 5.11 (mean ± SEM) letters. Late leakage on FA was scored as improved in four of five study eyes. These findings were not correlated with changes in hemoglobin A1c (HbA1c), creatinine, or blood pressure. Conclusions In this proof-of-concept study, dextromethorphan administration as the primary treatment for DME was associated with decreased vascular leakage, suggesting possible therapeutic effects. Additional studies investigating the modulation of microglial activation is warranted. Translational Relevance These findings highlight microglial modulation as a potentially useful therapeutic strategy in the treatment of diabetic macular edema.
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Affiliation(s)
- David J Valent
- Division of Epidemiology and Clinical Applications, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Wai T Wong
- Unit on Neuron-Glia Interactions in Retinal Disease, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Emily Y Chew
- Division of Epidemiology and Clinical Applications, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Catherine A Cukras
- Division of Epidemiology and Clinical Applications, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
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Katz JL, Hiranita T, Hong WC, Job MO, McCurdy CR. A Role for Sigma Receptors in Stimulant Self-Administration and Addiction. Handb Exp Pharmacol 2017; 244:177-218. [PMID: 28110353 DOI: 10.1007/164_2016_94] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Sigma receptors (σRs) are structurally unique proteins that function intracellularly as chaperones. Historically, σRs have been implicated as modulators of psychomotor stimulant effects and have at times been proposed as potential avenues for modifying stimulant abuse. However, the influence of ligands for σRs on the effects of stimulants, such as cocaine or methamphetamine, in various preclinical procedures related to drug abuse has been varied. The present paper reviews the effects of σR agonists and antagonists in three particularly relevant procedures: stimulant discrimination, place conditioning, and self-administration. The literature to date suggests limited σR involvement in the discriminative-stimulus effects of psychomotor stimulants, either with σR agonists substituting for the stimulant or with σR antagonists blocking stimulant effects. In contrast, studies of place conditioning suggest that administration of σR antagonists or down-regulation of σR protein can block the place conditioning induced by stimulants. Despite place conditioning results, selective σR antagonists are inactive in blocking the self-administration of stimulants. However, compounds binding to the dopamine transporter and blocking σRs can selectively decrease stimulant self-administration. Further, after self-administration of stimulants, σR agonists are self-administered, an effect not seen in subjects without that specific history. These findings suggest that stimulants induce unique changes in σR activity, and once established, the changes induced create redundant, and dopamine independent reinforcement pathways. Concomitant targeting of both dopaminergic pathways and σR proteins produces a selective antagonism of those pathways, suggesting new avenues for combination chemotherapies to specifically combat stimulant abuse.
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Affiliation(s)
- Jonathan L Katz
- Psychobiology Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, MD, 21224, USA.
| | - Takato Hiranita
- Psychobiology Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, MD, 21224, USA
| | - Weimin C Hong
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, IN, 46208, USA
| | - Martin O Job
- Psychobiology Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, MD, 21224, USA
| | - Christopher R McCurdy
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, MS, 38677, USA
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Abstract
This chapter presents the three-dimensional (3D) model of the Sigma1 receptor protein as obtained from homology modeling techniques. We show the applicability of this structure to docking-based virtual screening and discuss combined in silico/in vitro mutagenesis studies performed to validate the structural features of the Sigma1 receptor model and to qualify/quantify the prominent role of specific amino acid residues in ligand binding. The validation of the virtual 3D Sigma1 receptor model and its reliable applicability to docking-based virtual screening is of significance for rational ligand design, even in light of the recently reported crystal structure for the Sigma1 receptor.
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Affiliation(s)
- Erik Laurini
- Molecular Simulation Engineering (MOSE) Laboratory, Department of Engineering and Architecture (DEA), University of Trieste, Via Valerio 6, 34127, Trieste, Italy
| | - Domenico Marson
- Molecular Simulation Engineering (MOSE) Laboratory, Department of Engineering and Architecture (DEA), University of Trieste, Via Valerio 6, 34127, Trieste, Italy
| | - Maurizio Fermeglia
- Molecular Simulation Engineering (MOSE) Laboratory, Department of Engineering and Architecture (DEA), University of Trieste, Via Valerio 6, 34127, Trieste, Italy
| | - Sabrina Pricl
- Molecular Simulation Engineering (MOSE) Laboratory, Department of Engineering and Architecture (DEA), University of Trieste, Via Valerio 6, 34127, Trieste, Italy.
- National Interuniversity Consortium for Material Science and Technology (INSTM), Research Unit MOSE-DEA, University of Trieste, Via Valerio 6, 34127, Trieste, Italy.
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Garay RP, Grossberg GT. AVP-786 for the treatment of agitation in dementia of the Alzheimer's type. Expert Opin Investig Drugs 2016; 26:121-132. [PMID: 27936965 DOI: 10.1080/13543784.2017.1267726] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Agitation is common and distressing in patients with Alzheimer-type dementia, but safe, effective treatments remain elusive. Psychological treatments are first-line options, but they have limited efficacy. Off-label psychotropic medications are frequently used, but they also have limited effectiveness, and their use may have harmful side effects, including death. Areas covered: This review discusses the history leading to the conception of AVP-786 (deuterated (d6)-dextromethorphan/quinidine), its pharmacokinetic and pharmacodynamic profiles and safety issues, together with an overview of recent clinical trials. Data were found in the medical literature, in US and EU clinical trial registries and in information provided by the manufacturer. Expert opinion: AVP-786 is one of six investigational compounds in recent phase III clinical development for agitation in Alzheimer disease (AD). Quinidine and deuteration appear to prolong dextromethorphan's plasma half-life and facilitate brain penetration. The FDA granted fast-track designation to AVP-786 and allowed use of data generated on dextromethorphan-quinidine (AVP-923, Nuedexta®) for regulatory filings. AVP-923 reduced agitation in AD and was well tolerated in a phase II RCT that included more than 200 patients. A phase III clinical development program of AVP-786 for AD agitation was recently initiated. This program is expected to start generating results in July 2018.
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Affiliation(s)
- Ricardo P Garay
- a Geriatric Psychiatry, Department of Psychiatry and Behavioural Neuroscience , Pharmacology and Therapeutics, Craven , Villemoisson-sur-Orge , France
| | - George T Grossberg
- b Department of Psychiatry and Behavioural Neuroscience , St Louis University School of Medicine , St Louis , MO , USA
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14
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Taylor CP, Traynelis SF, Siffert J, Pope LE, Matsumoto RR. Pharmacology of dextromethorphan: Relevance to dextromethorphan/quinidine (Nuedexta®) clinical use. Pharmacol Ther 2016; 164:170-82. [PMID: 27139517 DOI: 10.1016/j.pharmthera.2016.04.010] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Dextromethorphan (DM) has been used for more than 50years as an over-the-counter antitussive. Studies have revealed a complex pharmacology of DM with mechanisms beyond blockade of N-methyl-d-aspartate (NMDA) receptors and inhibition of glutamate excitotoxicity, likely contributing to its pharmacological activity and clinical potential. DM is rapidly metabolized to dextrorphan, which has hampered the exploration of DM therapy separate from its metabolites. Coadministration of DM with a low dose of quinidine inhibits DM metabolism, yields greater bioavailability and enables more specific testing of the therapeutic properties of DM apart from its metabolites. The development of the drug combination DM hydrobromide and quinidine sulfate (DM/Q), with subsequent approval by the US Food and Drug Administration for pseudobulbar affect, led to renewed interest in understanding DM pharmacology. This review summarizes the interactions of DM with brain receptors and transporters and also considers its metabolic and pharmacokinetic properties. To assess the potential clinical relevance of these interactions, we provide an analysis comparing DM activity from in vitro functional assays with the estimated free drug DM concentrations in the brain following oral DM/Q administration. The findings suggest that DM/Q likely inhibits serotonin and norepinephrine reuptake and also blocks NMDA receptors with rapid kinetics. Use of DM/Q may also antagonize nicotinic acetylcholine receptors, particularly those composed of α3β4 subunits, and cause agonist activity at sigma-1 receptors.
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Affiliation(s)
| | - Stephen F Traynelis
- Dept. of Pharmacology, Emory University School of Medicine, Atlanta, GA, USA
| | - Joao Siffert
- Avanir Pharmaceuticals, Inc., Aliso Viejo, CA, USA
| | - Laura E Pope
- Avanir Pharmaceuticals, Inc., Aliso Viejo, CA, USA
| | - Rae R Matsumoto
- College of Pharmacy, Touro University California, Vallejo, CA, USA
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15
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Nguyen L, Thomas KL, Lucke-Wold BP, Cavendish JZ, Crowe MS, Matsumoto RR. Dextromethorphan: An update on its utility for neurological and neuropsychiatric disorders. Pharmacol Ther 2016; 159:1-22. [PMID: 26826604 DOI: 10.1016/j.pharmthera.2016.01.016] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Dextromethorphan (DM) is a commonly used antitussive and is currently the only FDA-approved pharmaceutical treatment for pseudobulbar affect. Its safety profile and diverse pharmacologic actions in the central nervous system have stimulated new interest for repurposing it. Numerous preclinical investigations and many open-label or blinded clinical studies have demonstrated its beneficial effects across a variety of neurological and psychiatric disorders. However, the optimal dose and safety of chronic dosing are not fully known. This review summarizes the preclinical and clinical effects of DM and its putative mechanisms of action, focusing on depression, stroke, traumatic brain injury, seizure, pain, methotrexate neurotoxicity, Parkinson's disease and autism. Moreover, we offer suggestions for future research with DM to advance the treatment for these and other neurological and psychiatric disorders.
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Affiliation(s)
- Linda Nguyen
- Department of Behavioral Medicine and Psychiatry, School of Medicine, West Virginia University, Morgantown, WV 26506, USA; Department of Pharmaceutical Sciences, School of Pharmacy, West Virginia University, Morgantown, WV 26506, USA
| | - Kelan L Thomas
- College of Pharmacy, Touro University California, Vallejo, CA 94592, USA
| | - Brandon P Lucke-Wold
- Graduate Program in Neuroscience, School of Medicine, West Virginia University, Morgantown, WV 26506, USA
| | - John Z Cavendish
- Graduate Program in Neuroscience, School of Medicine, West Virginia University, Morgantown, WV 26506, USA
| | - Molly S Crowe
- Department of Psychology, West Virginia University, Morgantown, WV 26506, USA
| | - Rae R Matsumoto
- Department of Behavioral Medicine and Psychiatry, School of Medicine, West Virginia University, Morgantown, WV 26506, USA; College of Pharmacy, Touro University California, Vallejo, CA 94592, USA.
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16
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Guo L, Chen Y, Zhao R, Wang G, Friedman E, Zhang A, Zhen X. Allosteric modulation of sigma-1 receptors elicits anti-seizure activities. Br J Pharmacol 2015; 172:4052-65. [PMID: 25989224 PMCID: PMC4543612 DOI: 10.1111/bph.13195] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 04/30/2015] [Accepted: 05/05/2015] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND AND PURPOSE Application of orthosteric sigma-1 receptor agonists as anti-seizure drugs has been hindered by questionable efficacy and potential adverse effects. Here, we have investigated the anti-seizure effects of the novel and potent allosteric modulator of sigma-1 receptors, SKF83959 and its derivative SOMCL-668 (3-methyl-phenyl-2,3,4,5-tetrahydro-1H-benzo[d]azepin-7-ol). EXPERIMENTAL APPROACH The anti-seizure effects of SKF83959 were investigated in three mouse models, maximal electroshock seizures, pentylenetetrazole-induced convulsions and kainic acid-induced 'status epilepticus'. Also, in rats, the cortical epileptiform activity induced by topical application of picrotoxin was recorded in electrocorticograms. In rat hippocampal brain slices, effects of the drugs on the high potassium-evoked epileptiform local field potentials were studied. Anti-seizure activities of SOMCL-668, a newly developed sigma-1 receptor selective allosteric modulator, were also investigated. KEY RESULTS SKF83959 (20, 40 mg·kg(-1) ) exhibited anti -seizure actitity in the three mouse models and reduced the cortical epileptiform activity without alteration of spontaneous motor activity and motor coordination. These effects were blocked by the sigma-1 receptor antagonist BD1047, but not the dopamine D1 receptor antagonist SCH23390. SKF83959 alone did not directly inhibit the epileptiform firing of CA3 neurons induced by high potassium in hippocampal slices, but did potentiate inhibition by the orthosteric sigma-1 receptor agonist SKF10047. Lastly, a selective sigma-1 receptor allosteric modulator SOMCL-668, which does not bind to dopamine receptors, exerted similar anti-seizure activities. CONCLUSIONS AND IMPLICATIONS SKF83959 and SOMCL-668 displayed anti-seizure activities, indicating that allosteric modulation of sigma-1 receptors may provide a novel approach for discovering new anti-seizure drugs.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/analogs & derivatives
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/pharmacology
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/therapeutic use
- Animals
- Anticonvulsants/pharmacology
- Anticonvulsants/therapeutic use
- Benzazepines/pharmacology
- Benzazepines/therapeutic use
- Hippocampus/drug effects
- Hippocampus/physiology
- Male
- Mice, Inbred C57BL
- Motor Activity/drug effects
- Rats, Sprague-Dawley
- Receptors, sigma/metabolism
- Seizures/drug therapy
- Seizures/metabolism
- Sigma-1 Receptor
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Affiliation(s)
- Lin Guo
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsycho-Disorders and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow UniversitySuzhou, Jiangsu Province, China
| | - Yanke Chen
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsycho-Disorders and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow UniversitySuzhou, Jiangsu Province, China
| | - Rui Zhao
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsycho-Disorders and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow UniversitySuzhou, Jiangsu Province, China
| | - Guanghui Wang
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsycho-Disorders and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow UniversitySuzhou, Jiangsu Province, China
| | - Eitan Friedman
- Department of Pharmacology and Neuroscience, School of Medicine at CCNY, City University of New YorkNew York, NY, USA
| | - Ao Zhang
- Department of Medicinal Chemistry, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghai, China
| | - Xuechu Zhen
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsycho-Disorders and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow UniversitySuzhou, Jiangsu Province, China
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17
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Liu H, Zheng WY, Ou XF, Ju XL. An Efficient Synthesis of Dimemorfan from Dextromethorphan. ORG PREP PROCED INT 2015. [DOI: 10.1080/00304948.2015.1025015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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18
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Tan H, Peng J, Pei Q, Yang L, Chen J, Guo C, Hua Y, Yuan H, Yang G. Simple and sensitive LC-MS/MS-based assay for the quantification of dimemorfan in human plasma for use in a pharmacokinetic study. Biomed Chromatogr 2014; 29:647-53. [PMID: 25262813 DOI: 10.1002/bmc.3325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 07/17/2014] [Accepted: 08/12/2014] [Indexed: 11/09/2022]
Abstract
Dimemorfan phosphate has been widely used for 40 years throughout the world for the treatment of coughs. This is the first report on the use of an LC-MS/MS-based assay for the determination of dimemorfan in human plasma using estazolam as an internal standard after one-step protein precipitation with acetonitrile. Chromatographic separation was achieved on a Phenomenex Luna C18 column (3 µm, 50 × 2.0 mm) using a fast gradient method, which involves water and methanol as the mobile phase (both containing 0.1% formic acid). Dimemorfan and estazolam were detected with proton adducts at m/z values of 255.8 → 155.1 and 295.0 → 267.0, respectively, in the selected reaction monitoring positive mode. The linear dynamic range of the assay was 0.04-5.00 ng/mL. The chromatographic run time for each plasma sample was <5 min. The method was proven to be accurate, precise, and repeatable. Finally, the developed method was successfully applied for the determination of dimemorfan in a pharmacokinetic study using healthy Chinese subjects.
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Affiliation(s)
- Hongyi Tan
- Center of Clinical Pharmacology, Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China
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19
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Dicpinigaitis PV, Morice AH, Birring SS, McGarvey L, Smith JA, Canning BJ, Page CP. Antitussive drugs--past, present, and future. Pharmacol Rev 2014; 66:468-512. [PMID: 24671376 PMCID: PMC11060423 DOI: 10.1124/pr.111.005116] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Cough remains a serious unmet clinical problem, both as a symptom of a range of other conditions such as asthma, chronic obstructive pulmonary disease, gastroesophageal reflux, and as a problem in its own right in patients with chronic cough of unknown origin. This article reviews our current understanding of the pathogenesis of cough and the hypertussive state characterizing a number of diseases as well as reviewing the evidence for the different classes of antitussive drug currently in clinical use. For completeness, the review also discusses a number of major drug classes often clinically used to treat cough but that are not generally classified as antitussive drugs. We also reviewed a number of drug classes in various stages of development as antitussive drugs. Perhaps surprising for drugs used to treat such a common symptom, there is a paucity of well-controlled clinical studies documenting evidence for the use of many of the drug classes in use today, particularly those available over the counter. Nonetheless, there has been a considerable increase in our understanding of the cough reflex over the last decade that has led to a number of promising new targets for antitussive drugs being identified and thus giving some hope of new drugs being available in the not too distant future for the treatment of this often debilitating symptom.
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Affiliation(s)
- P V Dicpinigaitis
- King's College London, Franklin Wilkins Building, 100 Stamford St., London, SE1 9NH, UK.
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20
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Morris H, Wallach J. From PCP to MXE: a comprehensive review of the non-medical use of dissociative drugs. Drug Test Anal 2014; 6:614-32. [DOI: 10.1002/dta.1620] [Citation(s) in RCA: 170] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Revised: 01/15/2014] [Accepted: 01/16/2014] [Indexed: 12/19/2022]
Affiliation(s)
- Hamilton Morris
- The New School, Department of Anthropology; 66 W 12th Street New York NY 10011 USA
| | - Jason Wallach
- Department of Pharmaceutical Sciences; University of the Sciences, Pharmaceutical Sciences; 400 South 43rd Street Philadelphia PA 19104 USA
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21
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Nguyen L, Robson MJ, Healy JR, Scandinaro AL, Matsumoto RR. Involvement of sigma-1 receptors in the antidepressant-like effects of dextromethorphan. PLoS One 2014; 9:e89985. [PMID: 24587167 PMCID: PMC3938562 DOI: 10.1371/journal.pone.0089985] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 01/25/2014] [Indexed: 12/30/2022] Open
Abstract
Dextromethorphan is an antitussive with a high margin of safety that has been hypothesized to display rapid-acting antidepressant activity based on pharmacodynamic similarities to the N-methyl-D-aspartate (NMDA) receptor antagonist ketamine. In addition to binding to NMDA receptors, dextromethorphan binds to sigma-1 (σ1) receptors, which are believed to be protein targets for a potential new class of antidepressant medications. The purpose of this study was to determine whether dextromethorphan elicits antidepressant-like effects and the involvement of σ1 receptors in mediating its antidepressant-like actions. The antidepressant-like effects of dextromethorphan were assessed in male, Swiss Webster mice using the forced swim test. Next, σ1 receptor antagonists (BD1063 and BD1047) were evaluated in conjunction with dextromethorphan to determine the involvement of σ receptors in its antidepressant-like effects. Quinidine, a cytochrome P450 (CYP) 2D6 inhibitor, was also evaluated in conjunction with dextromethorphan to increase the bioavailability of dextromethorphan and reduce exposure to additional metabolites. Finally, saturation binding assays were performed to assess the manner in which dextromethorphan interacts at the σ1 receptor. Our results revealed dextromethorphan displays antidepressant-like effects in the forced swim test that can be attenuated by pretreatment with σ1 receptor antagonists, with BD1063 causing a shift to the right in the dextromethorphan dose response curve. Concomitant administration of quinidine potentiated the antidepressant-like effects of dextromethorphan. Saturation binding assays revealed that a Ki concentration of dextromethorphan reduces both the Kd and the Bmax of [(3)H](+)-pentazocine binding to σ1 receptors. Taken together, these data suggest that dextromethorphan exerts some of its antidepressant actions through σ1 receptors.
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Affiliation(s)
- Linda Nguyen
- Department of Basic Pharmaceutical Sciences, and Department of Behavioral Medicine and Psychiatry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Matthew J. Robson
- Department of Basic Pharmaceutical Sciences, and Department of Behavioral Medicine and Psychiatry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Jason R. Healy
- Department of Basic Pharmaceutical Sciences, and Department of Behavioral Medicine and Psychiatry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Anna L. Scandinaro
- Department of Basic Pharmaceutical Sciences, and Department of Behavioral Medicine and Psychiatry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Rae R. Matsumoto
- Department of Basic Pharmaceutical Sciences, and Department of Behavioral Medicine and Psychiatry, West Virginia University, Morgantown, West Virginia, United States of America
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22
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Sromek AW, Provencher BA, Russell S, Chartoff E, Knapp BI, Bidlack JM, Neumeyer JL. Preliminary pharmacological evaluation of enantiomeric morphinans. ACS Chem Neurosci 2014; 5:93-9. [PMID: 24393077 PMCID: PMC3930996 DOI: 10.1021/cn400205z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
A series of levo- and dextromorphinan pairs have been synthesized and evaluated for their affinities to the mu, kappa, and delta opioid receptors, the N-methyl-D-aspartate (NMDA) channel, and sigma 1 and 2 receptors. It was found that levo isomers tended to have higher affinities at the opioid receptors and moderate to high affinities to the NMDA and sigma receptors, while dextro isomers tended to have lower affinities to the opioid receptors but comparatively higher affinities to the NMDA and sigma receptors. This series of compounds have interesting and complex pharmacological profiles, and merit further investigation as potential therapies for drug abuse treatment.
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Affiliation(s)
- Anna W Sromek
- Alcohol & Drug Abuse Research Center, ‡Mailman Research Center, McLean Hospital, Harvard Medical School , 115 Mill Street, Belmont, Massachusetts 02478, United States
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23
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Chary M, Park EH, McKenzie A, Sun J, Manini AF, Genes N. Signs & symptoms of Dextromethorphan exposure from YouTube. PLoS One 2014; 9:e82452. [PMID: 24533044 PMCID: PMC3922701 DOI: 10.1371/journal.pone.0082452] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 10/23/2013] [Indexed: 11/23/2022] Open
Abstract
Detailed data on the recreational use of drugs are difficult to obtain through traditional means, especially for substances like Dextromethorphan (DXM) which are available over-the-counter for medicinal purposes. In this study, we show that information provided by commenters on YouTube is useful for uncovering the toxicologic effects of DXM. Using methods of computational linguistics, we were able to recreate many of the clinically described signs and symptoms of DXM ingestion at various doses, using information extracted from YouTube comments. Our study shows how social networks can enhance our understanding of recreational drug effects.
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Affiliation(s)
- Michael Chary
- Ichan School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Emily H. Park
- Rutgers New Jersey Medical School, Newark, New Jersey, United States of America
| | - Andrew McKenzie
- Ichan School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Julia Sun
- Ichan School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Alex F. Manini
- Division of Medical Toxicology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Nicholas Genes
- Department of Emergency Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- * E-mail:
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24
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Meuwese JDI, van Loon AM, Scholte HS, Lirk PB, Vulink NCC, Hollmann MW, Lamme VAF. NMDA receptor antagonist ketamine impairs feature integration in visual perception. PLoS One 2013; 8:e79326. [PMID: 24223927 PMCID: PMC3815103 DOI: 10.1371/journal.pone.0079326] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 09/22/2013] [Indexed: 11/28/2022] Open
Abstract
Recurrent interactions between neurons in the visual cortex are crucial for the integration of image elements into coherent objects, such as in figure-ground segregation of textured images. Blocking N-methyl-D-aspartate (NMDA) receptors in monkeys can abolish neural signals related to figure-ground segregation and feature integration. However, it is unknown whether this also affects perceptual integration itself. Therefore, we tested whether ketamine, a non-competitive NMDA receptor antagonist, reduces feature integration in humans. We administered a subanesthetic dose of ketamine to healthy subjects who performed a texture discrimination task in a placebo-controlled double blind within-subject design. We found that ketamine significantly impaired performance on the texture discrimination task compared to the placebo condition, while performance on a control fixation task was much less impaired. This effect is not merely due to task difficulty or a difference in sedation levels. We are the first to show a behavioral effect on feature integration by manipulating the NMDA receptor in humans.
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Affiliation(s)
- Julia D. I. Meuwese
- Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands
- Cognitive Science Center Amsterdam, University of Amsterdam, Amsterdam, The Netherlands
- * E-mail:
| | - Anouk M. van Loon
- Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands
- Cognitive Science Center Amsterdam, University of Amsterdam, Amsterdam, The Netherlands
| | - H. Steven Scholte
- Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands
- Cognitive Science Center Amsterdam, University of Amsterdam, Amsterdam, The Netherlands
| | - Philipp B. Lirk
- Department of Anesthesiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Nienke C. C. Vulink
- Department of Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Markus W. Hollmann
- Department of Anesthesiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Victor A. F. Lamme
- Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands
- Cognitive Science Center Amsterdam, University of Amsterdam, Amsterdam, The Netherlands
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25
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Novel antitussive strategies. Drug Discov Today 2012; 18:380-8. [PMID: 23159360 DOI: 10.1016/j.drudis.2012.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 10/17/2012] [Accepted: 11/08/2012] [Indexed: 01/25/2023]
Abstract
Acute and chronic cough represent one of the most common symptoms of medical importance but effective pharmacotherapy is, to all intents and purposes, absent. Numerous initiatives targeting the recently discovered tussive pathways are in progress. Here, we review the current antitussive armamentarium and provide an update on the novel strategies and compounds in development.
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26
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Shin EJ, Bach JH, Lee SY, Kim JM, Lee J, Hong JS, Nabeshima T, Kim HC. Neuropsychotoxic and Neuroprotective Potentials of Dextromethorphan and Its Analogs. J Pharmacol Sci 2011; 116:137-48. [DOI: 10.1254/jphs.11r02cr] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Mutschler J, Koopmann A, Grosshans M, Hermann D, Mann K, Kiefer F. Dextromethorphan withdrawal and dependence syndrome. DEUTSCHES ARZTEBLATT INTERNATIONAL 2010; 107:537-40. [PMID: 20737060 DOI: 10.3238/arztebl.2010.0537] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Accepted: 12/11/2009] [Indexed: 11/27/2022]
Abstract
BACKGROUND The N-methyl-D-aspartate (NMDA) antagonist dextromethorphan has been available in pharmacies without a prescription since 1954 as an antitussive agent. There is an alarming increase in reports of its abuse. Dextromethorphan is avidly taken, mainly by young people, as a psychoactive drug. The currently available data yield incomplete information about the extent of the problem and its significance for addiction medicine in Germany. CASE PRESENTATION AND COURSE We report the case of a 44-year-old man who became dependent on dextromethorphan through years of abuse, buying the substance for himself without a prescription in German pharmacies. He told us he had taken it regularly for six years. He had become dependent on dextromethorphan, ultimately taking it in a dose of 1800 mg daily. This led him to overt neglect of his work and leisure activities. A urine sample taken on admission to the hospital was found to contain dextromethorphan. During inpatient detoxification, he developed an vegetative withdrawal syndrome consisting of craving, diaphoresis, nausea, hypertension, and tachycardia. He was treated on our ward for three weeks, and a stay in a residential detoxification facility was planned thereafter. CONCLUSION Dextromethorphan is a psychotropic substance that carries a potential for abuse and dependence. On the basis of the currently available data, its reclassification as a prescription drug should be considered.
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Affiliation(s)
- Jochen Mutschler
- Klinik für Abhängiges Verhalten und Suchtmedizin, Zentralinstitut für Seelische Gesundheit, Universität Heidelberg.
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28
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Abstract
Originally considered an enigmatic protein, the sigma-1 receptor has recently been identified as a unique ligand-regulated molecular chaperone in the endoplasmic reticulum of cells. This discovery causes us to look back at the many proposed roles of this receptor, even before its molecular function was identified, in many diseases such as methamphetamine or cocaine addiction, amnesia, pain, depression, Alzheimer's disease, stroke, retinal neuroprotection, HIV infection, and cancer. In this review, we examine the reports that have clearly shown an agonist-antagonist relationship regarding sigma-1 receptors in models of those diseases and also review the relatively known mechanisms of action of sigma-1 receptors in an attempt to spur the speculation of readers on how the sigma-1 receptor at the endoplasmic reticulum might relate to so many diseases. We found that the most prominent action of sigma-1 receptors in biological systems including cell lines, primary cultures, and animals is the regulation and modulation of voltage-regulated and ligand-gated ion channels, including Ca(2+)-, K(+)-, Na(+), Cl(-), and SK channels, and NMDA and IP3 receptors. We found that the final output of the action of sigma-1 receptor agonists is to inhibit all above-mentioned voltage-gated ion channels, while they potentiate ligand-gated channels. The inhibition or potentiation induced by agonists is blocked by sigma-1 receptor antagonists. Other mechanisms of action of sigma-1 receptors, and to some extent those of sigma-2 receptors, were also considered. We conclude that the sigma-1 and sigma-2 receptors represent potential fruitful targets for therapeutic developments in combating many human diseases.
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Affiliation(s)
- Tangui Maurice
- Team II Endogenous Neuroprotection in Neurodegenerative Diseases, INSERM U. 710, 34095 Montpellier Cedex 5, France
- University of Montpellier II, EPHE, CC 105, Place Eugene Bataillon, 34095 Montpellier Cedex 5, France
- EPHE, 75017 Paris, France
| | - Tsung-Ping Su
- Cellular Pathobiology Section, Cellular Neurobiology Research Branch, IRP, NIDA-NIH, Suite 3304, 333 Cassell Drive, Baltimore, MD 21224
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Wang YH, Shen YC, Liao JF, Lee CH, Li CH, Chou CY, Liou KT, Chou YC. Anti-inflammatory effects of dimemorfan on inflammatory cells and LPS-induced endotoxin shock in mice. Br J Pharmacol 2008; 154:1327-38. [PMID: 18500357 DOI: 10.1038/bjp.2008.202] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND PURPOSE Dimemorfan (a sigma1 receptor agonist) showed neuroprotective properties in animal models of inflammation-mediated neurodegenerative conditions, but its effects on inflammatory cells and systemic inflammation remain unclear. EXPERIMENTAL APPROACH The effects of dimemorfan on phorbol-12-myristate-13-acetate (PMA)- and N-formyl-methionyl-leucyl-phenylalanine (fMLP)- induced neutrophils and lipopolysaccharide (LPS)-activated microglial cells, as well as LPS-induced endotoxin shock in mice were elucidated. KEY RESULTS Dimemorfan decreased PMA- and fMLP-induced production of reactive oxygen species (ROS) and CD11b expression in neutrophils, through mechanisms independent of sigma1 receptors, possibly by blocking ROS production and G-protein-mediated intracellular calcium increase. Dimemorfan also inhibited LPS-induced ROS and nitric oxide (NO) production, as well as that of monocyte chemoattractant protein-1 and tumour necrosis factor-alpha (TNF-alpha), by inhibition of NADPH oxidase (NOX) activity and suppression of iNOS up-regulation through interfering with nuclear factor kappa-B (NF-kappaB) signalling in microglial cells. Treatment in vivo with dimemorfan (1 and 5 mg kg(-1), i.p., at three successive times after LPS) decreased plasma TNF-alpha, and neutrophil infiltration and oxidative stress in the lung and liver. CONCLUSIONS AND IMPLICATIONS Our results suggest that dimemorfan acts via sigma1 receptor-independent mechanisms to modulate intracellular calcium increase, NOX activity, and NF-kappaB signalling, resulting in inhibition of iNOS expression and NO production, and production of pro-inflammatory cytokines. These effects may contribute its anti-inflammatory action and protective effects against endotoxin shock in mice.
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Affiliation(s)
- Y-H Wang
- Department of Pharmacy, Taipei Veterans General Hospital, Taipei, Taiwan
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Shen YC, Wang YH, Chou YC, Liou KT, Yen JC, Wang WY, Liao JF. Dimemorfan protects rats against ischemic stroke through activation of sigma-1 receptor-mediated mechanisms by decreasing glutamate accumulation. J Neurochem 2008; 104:558-72. [PMID: 18173806 DOI: 10.1111/j.1471-4159.2007.05058.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Dimemorfan, an antitussive and a sigma-1 (sigma(1)) receptor agonist, has been reported to display neuroprotective properties. We set up an animal model of ischemic stroke injury by inducing cerebral ischemia (for 1 h) followed by reperfusion (for 24 h) (CI/R) in rats to examine the protective effects and action mechanisms of dimemorfan against stroke-induced damage. Treatment with dimemorfan (1.0 microg/kg and 10 microg/kg, i.v.) either 15 min before ischemia or at the time of reperfusion, like the putative sigma(1) receptor agonist, PRE084 (10 microg/kg, i.v.), ameliorated the size of the infarct zone by 67-72% or 51-52%, respectively, which was reversed by pre-treatment with the selective sigma(1) receptor antagonist, BD1047 (20 microg/kg, i.v.). Major pathological mechanisms leading to CI/R injury including excitotoxicity, oxidative/nitrosative stress, inflammation, and apoptosis are all downstream events initiated by excessive accumulation of extracellular glutamate. Dimemorfan treatment (10 microg/kg, i.v., at the time of reperfusion) inhibited the expressions of monocyte chemoattractant protein-1 and interleukin-1beta, which occurred in parallel with decreases in neutrophil infiltration, activation of inflammation-related signals (p38 mitogen-activated protein kinase, nuclear factor-kappaB, and signal transducer and activator of transcription-1), expression of neuronal and inducible nitric oxide synthase, oxidative/nitrosative tissue damage (lipid peroxidation, protein nitrosylation, and 8-hydroxy-guanine formation), and apoptosis in the ipsilateral cortex after CI/R injury. Dimemorfan treatment at the time of reperfusion, although did not prevent an early rise of glutamate level, significantly prevented subsequent glutamate accumulation after reperfusion. This inhibitory effect was lasted for more than 4 h and was reversed by pre-treatment with BD1047. These results suggest that dimemorfan activates the sigma(1) receptor to reduce glutamate accumulation and then suppresses initiation of inflammation-related events and signals as well as induction of oxidative and nitrosative stresses, leading to reductions in tissue damage and cell death. In conclusion, our results demonstrate for the first time that dimemorfan exhibits protective effects against ischemic stroke in CI/R rats probably through modulation of sigma(1) receptor-dependent signals to prevent subsequent glutamate accumulation and its downstream pathologic events.
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Affiliation(s)
- Yuh-Chiang Shen
- National Research Institute of Chinese Medicine, Taipei, Taiwan
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31
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Meurs A, Clinckers R, Ebinger G, Michotte Y, Smolders I. Sigma 1 receptor-mediated increase in hippocampal extracellular dopamine contributes to the mechanism of the anticonvulsant action of neuropeptide Y. Eur J Neurosci 2007; 26:3079-92. [PMID: 18005069 DOI: 10.1111/j.1460-9568.2007.05911.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The potent anticonvulsant properties of neuropeptide Y (NPY) are generally attributed to a Y2 receptor-mediated inhibition of glutamatergic synaptic transmission. Independent studies have shown that NPY increases brain dopamine content, possibly via interaction with sigma 1 receptors. Recently, we showed that increased extracellular hippocampal dopamine attenuates pilocarpine-induced limbic seizures via activation of hippocampal D2 receptors. Our aim in this study was to elucidate the role of increased hippocampal dopamine in the mechanism of the anticonvulsant action of NPY and to investigate the involvement of Y2 and sigma 1 receptors in this process. Limbic seizures were evoked in freely moving rats by intrahippocampal administration of pilocarpine via a microdialysis probe. NPY was administered intracerebroventricularly, intrahippocampally via the microdialysis probe, or coadministered intrahippocampally with the D2 receptor antagonist remoxipride, the Y2 receptor antagonist BIIE0246 or the sigma 1 receptor antagonist BD1047. Changes in hippocampal extracellular dopamine were monitored, and behavioural changes indicative of seizure activity were scored. Intracerebroventricular (10 nmol/3 microL) and intrahippocampal (20-50 microm) NPY administration increased hippocampal dopamine and attenuated pilocarpine-induced seizures. Hippocampal D2 receptor blockade (4 microm remoxipride) reversed the anticonvulsant effect of NPY. Y2 receptor blockade (1 microm BIIE0246) reversed the anticonvulsant effect of NPY but did not prevent NPY-induced increases in hippocampal dopamine. Sigma 1 receptor blockade (10 microm BD1047) abolished NPY-induced increases in hippocampal dopamine and reversed the anticonvulsant effect of NPY. Our results indicate that NPY-induced increases in hippocampal dopamine are mediated via sigma 1 receptors and contribute to the anticonvulsant effect of NPY via increased activation of hippocampal D2 receptors. This novel mechanism of anticonvulsant action of NPY is separate from, and may be complementary to, the well established Y2 receptor-mediated inhibition of hippocampal excitability.
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Affiliation(s)
- Alfred Meurs
- Department of Neurology, U. Z. Brussel, Laarbeeklaan 101,1090 Brussels, Belgium
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32
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Werling LL, Keller A, Frank JG, Nuwayhid SJ. A comparison of the binding profiles of dextromethorphan, memantine, fluoxetine and amitriptyline: Treatment of involuntary emotional expression disorder. Exp Neurol 2007; 207:248-57. [PMID: 17689532 DOI: 10.1016/j.expneurol.2007.06.013] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Revised: 06/15/2007] [Accepted: 06/20/2007] [Indexed: 10/23/2022]
Abstract
We compared the binding profiles of medications potentially useful in the treatment of involuntary emotional expression disorder at twenty-six binding sites in rat brain tissue membranes. Sites were chosen based on likelihood of being target sites for the mechanism of action of the agents in treating the disorder or their likelihood in producing side effects experienced by patients treated with psychoactive agents. We used radioligand binding assays employing the most selective labeled ligands available for sites of interest. Concentrations of labeled ligand were used at or below the K(i) value of the ligand for the target site. Compounds were initially screened at 1 muM. For compounds that competed for greater than 20-30% of specific binding at target sites of interest, full concentration curves were constructed. Dextromethorphan, amitriptyline and fluoxetine competed for binding to sigma(1) receptors and to serotonin transporters with high to moderate affinity. Of the target sites tested, these are the most likely to contribute to the therapeutic benefit of the various agents. In addition, all three drugs showed some activity at alpha(2) and 5-HT(1B/D) sites. Of the drugs tested, dextromethorphan bound to the fewest sites unlikely to be target sites. Although the mechanism of action of dextromethorphan or any drug that has been used in the treatment of involuntary emotional expression disorder is currently unknown, our data support that the affinity of the drug for sigma(1) receptors is consistent with its possible action through this receptor type in controlling symptoms of the disorder.
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Affiliation(s)
- Linda L Werling
- Department of Pharmacology and Physiology, The George Washington University Medical Center, Washington, DC 20037, USA.
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Werling LL, Lauterbach EC, Calef U. Dextromethorphan as a Potential Neuroprotective Agent With Unique Mechanisms of Action. Neurologist 2007; 13:272-93. [PMID: 17848867 DOI: 10.1097/nrl.0b013e3180f60bd8] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND Dextromethorphan (DM) is a widely-used antitussive. DM's complex central nervous system (CNS) pharmacology became of interest when it was discovered to be neuroprotective due to its low-affinity, uncompetitive N-methyl-D-aspartate (NMDA) receptor antagonism. REVIEW SUMMARY Mounting preclinical evidence has proven that DM has important neuroprotective properties in various CNS injury models, including focal and global ischemia, seizure, and traumatic brain injury paradigms. Many of these protective actions seem functionally related to its inhibitory effects on glutamate-induced neurotoxicity via NMDA receptor antagonist, sigma-1 receptor agonist, and voltage-gated calcium channel antagonist actions. DM's protection of dopamine neurons in parkinsonian models may be due to inhibition of neurodegenerative inflammatory responses. Clinical findings are limited, with preliminary evidence indicating that DM protects against neuronal damage. Negative findings seem to relate to attainment of inadequate DM brain concentrations. Small studies have shown some promise for treatment of perioperative brain injury, amyotrophic lateral sclerosis, and symptoms of methotrexate neurotoxicity. DM safety/tolerability trials in stroke, neurosurgery, and amyotrophic lateral sclerosis patients demonstrated a favorable safety profile. DM's limited clinical benefit is proposed to be associated with its rapid metabolism to dextrorphan, which restricts its central bioavailability and therapeutic utility. Systemic concentrations of DM can be increased via coadministration of low-dose quinidine (Q), which reversibly inhibits its first-pass elimination. Potential drug interactions with DM/Q are discussed. CONCLUSIONS Given the compelling preclinical evidence for neuroprotective properties of DM, initial clinical neuroprotective findings, and clinical demonstrations that the DM/Q combination is well tolerated, this strategy may hold promise for the treatment of various acute and degenerative neurologic disorders.
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Affiliation(s)
- Linda L Werling
- The Institute for Biomedical Sciences, The George Washington University Medical Center, Washington, DC, USA
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Smith RA. Dextromethorphan/quinidine: a novel dextromethorphan product for the treatment of emotional lability. Expert Opin Pharmacother 2007; 7:2581-98. [PMID: 17150011 DOI: 10.1517/14656566.7.18.2581] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Dextromethorphan (DM) is among the most widely used, non-narcotic antitussives, with a predictable safety profile. In 1981, a non-opioid, high-affinity brain recognition site for DM was discovered, and since then a unique neuropharmacological profile has emerged for this 'old' drug , suggesting novel applications. However, an extensive body of research for DM alone in treating various neurological conditions has been inconsistent. This may be largely due to its rapid first-pass metabolism. DM is currently being reintroduced as the active ingredient in a novel combination product in which low-dose quinidine is added to inhibit its breakdown, elevating blood levels of DM and increasing its likelihood of reaching neuronal targets . This has opened new possibilities for therapeutic use; the best evidence at present being for neurological disorders affecting emotional control.
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Affiliation(s)
- Richard Alan Smith
- Center for Neurologic Study, 9850 Genesee Ave, Suite 320, La Jolla, California 92037, USA.
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35
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Leke R, Oliveira DL, Schmidt AP, Avila TT, Jorge RS, Fischer A, Wofchuk S, Souza DO, Portela LV. Methotrexate induces seizure and decreases glutamate uptake in brain slices: Prevention by ionotropic glutamate receptors antagonists and adenosine. Life Sci 2006; 80:1-8. [PMID: 16962142 DOI: 10.1016/j.lfs.2006.08.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 05/21/2006] [Accepted: 08/14/2006] [Indexed: 12/20/2022]
Abstract
Methotrexate (MTX)-induced neurotoxicity may occur after intrathecal or systemic administration at low, intermediate and high doses for the treatment of malignant or inflammatory diseases. The mechanisms of MTX neurotoxicity are not totally understood, and appear to be multifactorial. In this study we characterized a model of MTX-induced seizures in mice to evaluate the convulsive and toxic MTX properties. Additionally, the effect of MTX-induced seizures on the activity of glutamate transporters, as well as the anticonvulsant role of MK-801, DNQX and adenosine on glutamate uptake in brain slices was investigated . MTX induced tonic-clonic seizures in approximately 95% of animals and pre-treatment with MK-801, DNQX and adenosine prevented seizure in 80%, 62% and 50% of animals, respectively. Moreover, MTX leads 59% of mice to death, which was prevented in 100% and 94% when animals received MK-801 and DNQX, respectively. Glutamate uptake decreased by 20% to 30% in cortical slices after MTX-induced seizures. Interestingly, when seizures were prevented by MK-801, DNQX or adenosine, glutamate uptake activity remained at the same level as the control group. Thus, our results demonstrate the involvement of the glutamatergic system in MTX-induced seizures.
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Affiliation(s)
- R Leke
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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36
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Wright MJ, Vann RE, Gamage TF, Damaj MI, Wiley JL. Comparative effects of dextromethorphan and dextrorphan on nicotine discrimination in rats. Pharmacol Biochem Behav 2006; 85:507-13. [PMID: 17112574 PMCID: PMC1847596 DOI: 10.1016/j.pbb.2006.09.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 09/08/2006] [Accepted: 09/27/2006] [Indexed: 11/23/2022]
Abstract
While the role of dextrorphan and dextromethorphan as N-methyl-d-aspartate (NMDA) receptor antagonists has received considerable research attention, their effects on nicotinic acetylcholine receptors (nAChR) has been less well characterized. Recent in vitro and in vivo research has suggested that these drugs noncompetitively block alpha3beta4*, alpha4beta2, and alpha7 nAChR subtypes and antagonize nicotine's antinociceptive and reinforcing effects. Both drugs were most potent at blocking alpha3beta4* AChR. This study investigated the effects of dextrorphan and dextromethorphan on nicotine's discriminative stimulus effects. Three groups of rats were trained in a two-lever drug discrimination procedure to discriminate 0.4 mg/kg s.c. nicotine from saline. Nicotine dose-dependently substituted for itself in all three groups. In contrast, when dextrorphan (group 1) or dextromethorphan (group 2) were injected i.p., neither substitution for nor antagonism of nicotine was observed for either drug. Since i.p. administration allows substantial metabolism of dextromethorphan to its parent compound dextrorphan, the two drugs were also tested following s.c. administration (group 3). Discrimination results were similar across both routes of administration, in that neither substitution nor antagonism occurred, however, s.c. administration reduced response rates to a much greater extent than did i.p. administration. Previous work suggests that beta2 subunits are crucial for mediation of nicotine's discriminative stimulus effects and may play a role in its reinforcing effects, albeit other research suggests a role for alpha3beta4* nicotinic receptors in the latter. Our results suggest that alpha3beta4* nicotinic receptors do not play a major role in nicotine's discriminative stimulus effects. Further, they suggest that the role of cholinergic mediation of the behavioral effects of dextrorphan and dextromethorphan related to the abuse properties of nicotine may be minimal.
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Affiliation(s)
| | | | | | | | - Jenny L. Wiley
- * To whom correspondence should be sent: Jenny Wiley, Ph.D., Department of Pharmacology & Toxicology, Virginia Commonwealth University, P.O. Box 980613, Richmond, VA 23298-0613, Phone: 804-828-2067, FAX: 804-828-2117, E-mail:
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Levin RM, Whitbeck C, Sourial MW, Tadrous M, Millington WR. Effects of dextromethorphan on in vitro contractile responses of mouse and rat urinary bladders. Neurourol Urodyn 2006; 25:802-7. [PMID: 16894613 DOI: 10.1002/nau.20306] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
PURPOSE Dextromethorphan (DXM) is a cough-suppressing ingredient in a variety of over-the-counter cough and cold medications. Dextromethorphan elevates the threshold for coughing primarily through a central mechanism. At doses recommended for treating coughs the drug is safe and effective. At much higher doses, DXM produces dissociative effects similar to those of phencyclidine and ketamine. Opioid analgesics structurally related to DXM also inhibit bladder contractions and produce urinary retention through a non-opioid mechanism. This study evaluated the direct effects of DXM on in vitro contractile responses of rat and mouse urinary bladders. METHODS Male rats and mice were anaesthetized and their bladders removed. Bladder strips were suspended in 15 ml oxygenated Tyrode's solution containing glucose. Bladder strip contractions were evoked by field stimulation (FS), carbachol or elevated KCl concentrations and contractile responses recorded. The strips were then exposed to 3 microM (DXM) for 30 min and re-stimulated. This sequence was repeated at 10, 30, and 100 microM DXM. RESULTS (a) The rat bladder generated significantly greater tension than the mouse bladder. (b) Dextromethorphan produced a dose-dependent inhibition of the response to FS that was approximately equal for rat and mouse bladders. FS at 8 or 32 Hz was significantly more sensitive to DXM inhibition than 2 Hz. (c) The response to carbachol was more sensitive to inhibition by DXM than the responses to FS or KCl. CONCLUSIONS These results demonstrate that DXM inhibits bladder contractions in vitro and that mouse and rat bladders are affected to approximately the same extent.
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Affiliation(s)
- Robert M Levin
- Division of Basic and Pharmaceutical Sciences, Albany College of Pharmacy, Albany, New York 12208, USA.
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Funck-Brentano C, Boëlle PY, Verstuyft C, Bornert C, Becquemont L, Poirier JM. Measurement of CYP2D6 and CYP3A4 activity in vivo with dextromethorphan: sources of variability and predictors of adverse effects in 419 healthy subjects. Eur J Clin Pharmacol 2005; 61:821-9. [PMID: 16315033 DOI: 10.1007/s00228-005-0051-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2005] [Accepted: 10/10/2005] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Dextromethorphan (DEM) shares part of the adverse event profile of opioids and is widely used as a probe drug for CYP2D6 phenotyping and for the assessment of CYP2D6 activity. It has also been used to assess CYP3A4 activity. This study examined the influence of anthropometric variables, oral contraceptives, smoking habits, mu-opioid receptor and MDR1 genetic polymorphisms and components of the DEM ratios on the variability of CYP2D6 and CYP3A4 metabolic ratios and on the occurrence of adverse events following DEM administration. METHODS This was a retrospective analysis of a database in 419 healthy subjects. CYP2D6 and CYP3A4 metabolic ratios were measured as the log of the ratios of the amount of DEM to the amount of dextrorphan (DOR) and of the amount of DEM to the amount of 3-methoxy-morphinan (MET) excreted in urine during a 12-h time period, respectively, following the oral administration of 80 mg of dextromethorphan hydrobromide. Logistic regression was performed to examine the factors associated with changes in metabolic ratios and with the occurrence of adverse events. RESULTS The CYP2D6 metabolic ratio allowed identification of extensive and poor metabolizers of DEM. The CYP2D6 and CYP3A4 metabolic ratios were not strictly independent one from each other. Based on multivariate analysis, the CYP2D6 metabolic ratio was a stronger independent predictor of adverse events (p<0.0001) than the CYP2D6 phenotype (p=0.05). Anthropometric variables, oral contraceptives, smoking habits, mu-opioid receptor and MDR1 genetic polymorphisms did not significantly contribute to changes in metabolic ratios or to the occurrence of adverse events. CONCLUSIONS Dextromethorphan can be used for CYP2D6 phenotyping, but the CYP2D6 and CYP3A4 metabolic ratios are not strictly independent one from each other. The CYP2D6 metabolic ratio predicts adverse events to DEM as does CYP2D6 phenotype, and extensive metabolizer subjects are not protected against adverse events.
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Affiliation(s)
- Christian Funck-Brentano
- INSERM--AP-HP, Clinical Investigation Center, CIC-9304, and Department of Pharmacology, Pierre et Marie Curie University, 75012 Paris, France.
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Shin EJ, Nah SY, Kim WK, Ko KH, Jhoo WK, Lim YK, Cha JY, Chen CF, Kim HC. The dextromethorphan analog dimemorfan attenuates kainate-induced seizures via sigma1 receptor activation: comparison with the effects of dextromethorphan. Br J Pharmacol 2005; 144:908-18. [PMID: 15723099 PMCID: PMC1576070 DOI: 10.1038/sj.bjp.0705998] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
In a previous study, we demonstrated that a dextromethorphan analog, dimemorfan, has neuroprotective effects. Dextromethorphan and dimemorfan are high-affinity ligands at sigma1 receptors. Dextromethorphan has moderate affinities for phencyclidine sites, while dimemorfan has very low affinities for such sites, suggesting that these sites are not essential for the anticonvulsant actions of dimemorfan. Kainate (KA) administration (10 mg kg(-1), i.p.) produced robust convulsions lasting 4-6 h in rats. Pre-treatment with dimemorfan (12 or 24 mg kg(-1)) reduced seizures in a dose-dependent manner. Dimemorfan pre-treatment also attenuated the KA-induced increases in c-fos/c-jun expression, activator protein (AP)-1 DNA-binding activity, and loss of cells in the CA1 and CA3 fields of the hippocampus. These effects of dimemorfan were comparable to those of dextromethorphan. The anticonvulsant action of dextromethorphan or dimemorfan was significantly counteracted by a selective sigma1 receptor antagonist BD 1047, suggesting that the anticonvulsant action of dextromethorphan or dimemorfan is, at least in part, related to sigma1 receptor-activated modulation of AP-1 transcription factors. We asked whether dimemorfan produces the behavioral side effects seen with dextromethorphan or dextrorphan (a phencyclidine-like metabolite of dextromethorphan). Conditioned place preference and circling behaviors were significantly increased in mice treated with phencyclidine, dextrorphan or dextromethorphan, while mice treated with dimemorfan showed no behavioral side effects. Our results suggest that dimemorfan is equipotent to dextromethorphan in preventing KA-induced seizures, while it may lack behavioral effects, such as psychotomimetic reactions.
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Affiliation(s)
- Eun-Joo Shin
- Neurotoxicology Program, College of Pharmacy, Korea Institute of Drug Abuse, Kangwon National University, Chunchon 200-701, South Korea
| | - Seung-Yeol Nah
- Department of Physiology, College of Veterinary Medicine, Konkuk University, Seoul, South Korea
| | - Won-Ki Kim
- Ewha Institute of Neuroscience, Ewha Womans University Medical School, Seoul, South Korea
| | - Kwang Ho Ko
- Department of Pharmacology, College of Pharmacy, Seoul National University, Seoul, South Korea
| | - Wang-Kee Jhoo
- Neurotoxicology Program, College of Pharmacy, Korea Institute of Drug Abuse, Kangwon National University, Chunchon 200-701, South Korea
| | - Yong-Kwang Lim
- Neurotoxicology Program, College of Pharmacy, Korea Institute of Drug Abuse, Kangwon National University, Chunchon 200-701, South Korea
| | - Joo Young Cha
- Neurotoxicology Program, College of Pharmacy, Korea Institute of Drug Abuse, Kangwon National University, Chunchon 200-701, South Korea
| | - Chieh-Fu Chen
- Department of Pharmacology, National Research Institute of Chinese Medicine, Taipei, Taiwan
| | - Hyoung-Chun Kim
- Neurotoxicology Program, College of Pharmacy, Korea Institute of Drug Abuse, Kangwon National University, Chunchon 200-701, South Korea
- Author for correspondence:
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Chow LH, Huang EYK, Ho ST, Tsai SK, Tao PL. Dextromethorphan potentiates morphine-induced antinociception at both spinal and supraspinal sites but is not related to the descending serotoninergic or adrenergic pathways. J Biomed Sci 2004; 11:717-25. [PMID: 15591767 DOI: 10.1007/bf02254355] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2004] [Accepted: 05/04/2004] [Indexed: 11/27/2022] Open
Abstract
Morphine is a strong and widely used opioid analgesic in pain management, but some adverse effects limit its clinical use at high doses. The clinically available non-opioid antitussive, dextromethorphan (DM) can potentiate the analgesic effect of morphine and decrease the dose of morphine in acute postoperative pain. However, the mechanism underlying this synergistic phenomenon is still not clear. To examine if the potentiation by DM occurs through the descending pain-inhibitory pathways, ketanserin (a 5-HT2 receptor antagonist) and yohimbine (an alpha2-adrenergic receptor antagonist) were employed and found to have no significant effect on the potentiation by DM. Using local delivery of drugs in rats in the present study, potentiation of morphine-induced antinociception by DM was observed via both intrathecal and intracerebroventricular routes, suggesting that both spinal and supraspinal sites are involved. This suggests that the potentiation of morphine-induced antinociception by DM is not mediated by the serotoninergic or adrenergic descending pain-inhibitory pathways. The present results are consistent with findings in clinical studies, which showed that DM can effectively decrease the consumption of morphine in patients suffering from pain. Since DM has excellent clinical potential as a synergistic agent with morphine, further investigating and clarifying the possible pharmacological mechanism of DM are of great importance for future studies.
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Affiliation(s)
- Lok-Hi Chow
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan, ROC
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Nemmani KVS, Grisel JE, Stowe JR, Smith-Carliss R, Mogil JS. Modulation of morphine analgesia by site-specific N-methyl-D-aspartate receptor antagonists: dependence on sex, site of antagonism, morphine dose, and time. Pain 2004; 109:274-283. [PMID: 15157688 DOI: 10.1016/j.pain.2004.01.035] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2003] [Revised: 12/18/2003] [Accepted: 01/12/2004] [Indexed: 11/28/2022]
Abstract
Pharmacological blockade of N-methyl-D-aspartate (NMDA) receptors can modulate morphine analgesia in experimental animals and humans. However, this literature is highly inconsistent, with NMDA receptor antagonists variously shown to potentiate, attenuate or produce no effect on morphine analgesic magnitude. A number of factors influencing this modulation have been proposed, but no one has examined such factors simultaneously, and all existing studies in mice were conducted exclusively in male subjects. Thus, the influence of systemic administration of site-specific NMDA receptor antagonists-including dextromethorphan, dextrorphan, MK-801, LY235959, L-701,324, and Ro 25-6981-on morphine analgesia (15-45 mg/kg; 15, 30 and 60 min post-injection) was studied in male and female mice using the 49 degrees C tail-withdrawal test. We found that oral and intraperitoneal dextromethorphan, a low-affinity non-competitive antagonist, dose-dependently potentiated low-dose morphine analgesia but attenuated high-dose morphine analgesia. Dextrorphan and MK-801 were found to potentiate low- but not high-dose morphine analgesia. The competitive glutamate-site antagonist, LY235959, and glycine-site antagonist, L-701,324, potentiated morphine analgesia at all doses. In contrast, the polyamine (NR2B) site antagonist, Ro 25-6981, attenuated morphine analgesia at all doses. Strikingly, the non-competitive antagonists produced no modulation of morphine analgesia whatsoever in female mice, whereas no sex differences were observed using competitive or NR2B antagonists. These findings indicate that NMDA modulation of morphine analgesia is critically influenced by sex, site of antagonism, morphine dose and time after injection. Our data suggest that NMDA antagonism via competitive or glycine site antagonism might result in more reliable clinical effects on morphine analgesia in both sexes.
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Affiliation(s)
- Kumar V S Nemmani
- Department of Psychology and Centre for Research on Pain, McGill University, 1205 Dr Penfield Ave., Montreal, QC, Canada H3A 1B1 Department of Psychology, Furman University, Greenville, SC 29613, USA Endo Pharmaceuticals Inc., Chadds Ford, PA 19317, USA
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Wang HH, Chou YC, Liao JF, Chen CF. Dimemorfan enhances acetylcholine release from rat hippocampal slices. Brain Res 2004; 1008:113-5. [PMID: 15081388 DOI: 10.1016/j.brainres.2004.02.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2004] [Indexed: 10/26/2022]
Abstract
Our previous study reported that an antitussive drug, dimemorfan, attenuates cholinergic dysfunction-induced amnesia in mice and acts like a sigma1 receptor agonist. This study further showed that dimemorfan (30 microM), like the putative sigma1 receptor agonist (+)-SKF-10047 (10 microM), significantly enhanced 25 mM KCl-evoked [3H]acetylcholine release from rat hippocampal but not striatal slices, which was antagonized by a sigma1 receptor antagonist haloperidol (0.3 microM).
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Affiliation(s)
- Hui-Hung Wang
- Department and Institute of Pharmacology, National Yang-Ming University, No. 155, Sec. 2, Li-Nong Street, Taipei, Taiwan
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Brown C, Fezoui M, Selig WM, Schwartz CE, Ellis JL. Antitussive activity of sigma-1 receptor agonists in the guinea-pig. Br J Pharmacol 2004; 141:233-40. [PMID: 14691051 PMCID: PMC1574192 DOI: 10.1038/sj.bjp.0705605] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2003] [Revised: 10/20/2003] [Accepted: 10/30/2003] [Indexed: 11/08/2022] Open
Abstract
1. Current antitussive medications have limited efficacy and often contain the opiate-like agent dextromethorphan (DEX). The mechanism whereby DEX inhibits cough is ill defined. DEX displays affinity at both NMDA and sigma receptors, suggesting that the antitussive activity may involve central or peripheral activity at either of these receptors. This study examined and compared the antitussive activity of DEX and various putative sigma receptor agonists in the guinea-pig citric-acid cough model. 2. Intraperitoneal (i.p.) administration of DEX (30 mg kg(-1)) and the sigma-1 agonists SKF-10,047 (1-5 mg kg(-1)), Pre-084 (5 mg kg(-1)), and carbetapentane (1-5 mg kg(-1)) inhibited citric-acid-induced cough in guinea-pigs. Intraperitoneal administration of a sigma-1 antagonist, BD 1047 (1-5 mg kg(-1)), reversed the inhibition of cough elicited by SKF-10,047. In addition, two structurally dissimilar sigma agonists SKF-10,047 (1 mg ml(-1)) and Pre-084 (1 mg ml(-1)) inhibited cough when administered by aerosol. 3. Aerosolized BD 1047 (1 mg ml(-1), 30 min) prevented the antitussive action of SKF-10,047 (5 mg kg(-1)) or DEX (30 mg kg(-1)) given by i.p. administration and, likewise, i.p. administration of BD 1047 (5 mg kg(-1)) prevented the antitussive action of SKF-10,047 given by aerosol (1 mg ml(-1)). 4. These results therefore support the argument that antitussive effects of DEX may be mediated via sigma receptors, since both systemic and aerosol administration of sigma-1 receptor agonists inhibit citric-acid-induced cough in guinea-pigs. While significant systemic exposure is possible with aerosol administration, the very low doses administered (estimated <0.3 mg kg(-1)) suggest that there may be a peripheral component to the antitussive effect.
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Affiliation(s)
- Claire Brown
- UCB Research Inc., UCB Pharma, 840 Memorial Drive, Cambridge, MA 02139, USA.
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Dere E, Topic B, De Souza Silva MA, Fink H, Buddenberg T, Huston JP. NMDA-receptor antagonism via dextromethorphan and ifenprodil modulates graded anxiety test performance of C57BL/6 mice. Behav Pharmacol 2003; 14:245-9. [PMID: 12799527 DOI: 10.1097/00008877-200305000-00009] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The majority of N-methyl-D-aspartate receptors (NMDA-R) in the adult forebrain are di- or triheteromers composed of NR1, NR2A and NR2B subunits. Subunit non-selective NMDA-R antagonists produce anxiolytic-like effects together with motor and sensory side-effects. The graded anxiety test (GAT), permits the within-task distinction of drug effects on anxiety from those on activity and perception. By testing NMDA-R subunit selective agents in the GAT it might be possible to determine whether their effects on anxiety, activity and perception are interrelated, and whether separate NMDA-R subtypes are involved. Dextromethorphan (weakly NR2A-selective) (10 and 30 mg/kg, i.p.) and ifenprodil (highly NR2B-selective) (1, 3 and 5 mg/kg, i.p.) were tested in the GAT. Both drugs failed to induce anxiolysis devoid of side-effects. However, the 10 mg/kg dose of dextromethorpan showed an anxiolytic, whereas the 30 mg/kg dose showed an anxiogenic, behavioral profile. Since the selective blockade of the NR2B subunit by ifenprodil had no clear anxiolytic effect, the anxiolytic potential of NMDA subunit non-selective agents might involve NR2A-containing receptors.
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Affiliation(s)
- E Dere
- Institute of Physiological Psychology, Center for Biological and Medical Research, University of Düsseldorf, Universitätstrasse 1, 40225 Düsseldorf, Germany.
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Abstract
(1) Dimemorfan, an antitussive for more than 25 years, has previously been reported to be a relative high-affinity ligand at sigma-1 (sigma(1)) receptor with the K(i) value of 151 nM. (2) To test whether dimemorfan has anti-amnesic effects similar to a sigma(1) receptor agonist, this study examined its effects on scopolamine- and beta-amyloid peptide-(25-35)-induced amnesia in mice. (3) Dimemorfan (10-40 mg kg(-1), i.p.) administered 30 min before the training trial, immediately after the training trial, or 30 min before the retention test significantly improved scopolamine (1 mg kg(-1), i.p.)- or beta-amyloid peptide-(25-35) (3 nmol mouse(-1), i.c.v.)-induced amnesia in a step-through passive avoidance test. Dimemorfan (5-40 mg kg(-1), i.p.) pretreatment also attenuated scopolamine (8 mg kg(-1), i.p.)-induced amnesia in a water-maze test. And, these anti-amnesic effects of dimemorfan, like the putative sigma(1) receptor agonist (+)-N-allylnormetazocine ((+)-SKF-10047), were antagonized by a sigma receptor antagonist haloperidol (0.25 mg kg(-1), i.p.). (4) These results indicated that dimemorfan has anti-amnesic effects and acts like a sigma(1) receptor agonist.
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Affiliation(s)
- Hui-Hung Wang
- Department & Institute of Pharmacology, National Yang-Ming University, No. 155, Sec. 2, Li-Nong Street, Taipei 112, Taiwan
| | - Jyh-Wei Chien
- Department & Institute of Pharmacology, National Yang-Ming University, No. 155, Sec. 2, Li-Nong Street, Taipei 112, Taiwan
| | - Yueh-Ching Chou
- Department of Pharmacy, Veterans General Hospital-Taipei, No. 201, Sec. 2, Shi-Pai Road, Taipei 112, Taiwan
| | - Jyh-Fei Liao
- Department & Institute of Pharmacology, National Yang-Ming University, No. 155, Sec. 2, Li-Nong Street, Taipei 112, Taiwan
- Author for correspondence:
| | - Chieh-Fu Chen
- National Research Institute of Chinese Medicine, No. 155-1, Sec. 2, Li-Nong Street, Taipei 112, Taiwan
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Beroza P, Villar HO, Wick MM, Martin GR. Chemoproteomics as a basis for post-genomic drug discovery. Drug Discov Today 2002; 7:807-14. [PMID: 12546968 DOI: 10.1016/s1359-6446(02)02371-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The large number of small organic compounds now available for drug-lead screening has led to numerous methods for classifying molecular similarity and diversity, the aim being to restore a balance between the quantity and drug-like quality of compounds in small-molecule libraries. Whereas structural and physicochemical attributes continue to be emphasized in compound selection for drug-lead screening, chemoproteomics--the use of biological information to guide chemistry--offers a highly efficient alternative to small-molecule characterization that can accelerate drug discovery in the post-genomic era.
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Affiliation(s)
- Paul Beroza
- Telik, 750 Gateway Blvd, South San Francisco, CA 94080, USA.
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Weinbroum AA, Lalayev G, Yashar T, Ben-Abraham R, Niv D, Flaishon R. Combined pre-incisional oral dextromethorphan and epidural lidocaine for postoperative pain reduction and morphine sparing: a randomised double-blind study on day-surgery patients. Anaesthesia 2001; 56:616-22. [PMID: 11437760 DOI: 10.1046/j.1365-2044.2001.02088.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The reduction in acute pain perception following dextromethorphan has previously been investigated in patients undergoing general anaesthesia. This random and double-blind study examined the effects of pre-incisional oral dextromethorphan on postoperative pain and intravenous patient-controlled morphine demand in 60 day-surgery patients undergoing lower body surgery under lidocaine (1.6%-16 ml) epidural anaesthesia after receiving placebo, 60 or 90 mg dextromethorphan, 90 min pre-operatively. Postoperative pain was scored on a visual analogue scale from 1 to 10. In-hospital observation continued for 6 h and for 3 days at home; diclofenac was available throughout. Dextromethorphan-treated patients reported significantly (p < 0.05) less pain and sedation, and felt better. Patients who received dextromethorphan 90 mg had significantly (p < 0.05) lower heart and respiratory rates than those who received 60 mg. Medicated patients required half the morphine and diclofenac of placebo patients: 38% of patients who received 90 mg and 21% who received dextromethorphan 60 mg used no morphine or diclofenac whatsoever, a previously unreported finding.
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Affiliation(s)
- A A Weinbroum
- Department of Anaesthesiology and Critical Care Medicine, Post-Anaesthesia Care Unit, and Pain Clinic, Tel Aviv Sourasky Medical Centre, 6 Weizman Street, Tel Aviv 64239, Israel.
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Kozela E, Danysz W, Popik P. Uncompetitive NMDA receptor antagonists potentiate morphine antinociception recorded from the tail but not from the hind paw in rats. Eur J Pharmacol 2001; 423:17-26. [PMID: 11438302 DOI: 10.1016/s0014-2999(01)01084-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We investigated the effects of pretreatment with low-affinity, uncompetitive NMDA receptor antagonists on morphine-induced antinociception in rats using the same intensity of thermal stimulus applied to the tail and the paws. Similar baseline responses to thermal stimuli of the same intensity were recorded from tails and hind paws. However, morphine produced equal antinociception from the tail and hind paw when used at doses of 2.5 and 6 mg/kg, respectively. These doses were used in further experiments. Thirty minutes before morphine, rats were administered the NMDA receptor antagonists dextromethorphan (2.5--30 mg/kg), memantine (2.5--15 mg/kg) and MRZ 2/579 (1-amino-1,3,3,5,5-pentamethyl-cyclohexane HCl) (1.25--10 mg/kg). All three compounds significantly and dose-dependently potentiated morphine-induced antinociception recorded from the tail. However, none of these NMDA receptor antagonists affected morphine antinociception recorded from the paw. These findings suggest that low-affinity NMDA receptor antagonists modulate differently morphine antinociceptive activity recorded from the tail and hind paws.
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Affiliation(s)
- E Kozela
- Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343, Kraków, Poland.
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Wang HH, Chou CJ, Liao JF, Chen CF. Dehydroevodiamine attenuates beta-amyloid peptide-induced amnesia in mice. Eur J Pharmacol 2001; 413:221-5. [PMID: 11226396 DOI: 10.1016/s0014-2999(00)00913-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dehydroevodiamine has been reported to have anticholinesterase activity and an anti-amnesic effect. This study examined the effects of dehydroevodiamine on scopolamine- and beta-amyloid peptide-(25--35)-induced amnesia in mice, using a step-through passive avoidance test. Similarly to the cholinesterase inhibitor, physostigmine (0.03--0.3 mg/kg, i.p.), dehydroevodiamine (0.75--12.0 mg/kg, i.p.) administered 30 min before the training trial, immediately after the training trial, and 30 min before the retention test significantly improved scopolamine- and beta-amyloid peptide-(25--35)-induced amnesia. In beta-amyloid peptide-(25--35)-induced amnesia, the rank order of anti-amnesic potency in these three administration schedules for dehydroevodiamine was different from that for physostigmine. Furthermore, dehydroevodiamine was more potent to improve beta-amyloid peptide-(25--35)-induced amnesia than scopolamine-induced amnesia when administered before the training trial. These results suggested that dehydroevodiamine may have an action other than that of an anticholinesterase and may be a novel and effective ligand for improvement of beta-amyloid type amnesia.
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Affiliation(s)
- H H Wang
- Department and Institute of Pharmacology, National Yang-Ming University, No. 155, Sec. 2, Li-Nong Street, Pei-Tou Dist. (112), Taipei (11221), Taiwan
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