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Pergolizzi JV, LeQuang JA, El-Tallawy SN, Wagner M, Ahmed RS, Varrassi G. An update on pharmacotherapy for trigeminal neuralgia. Expert Rev Neurother 2024:1-14. [PMID: 38870050 DOI: 10.1080/14737175.2024.2365946] [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: 03/28/2024] [Accepted: 06/05/2024] [Indexed: 06/15/2024]
Abstract
INTRODUCTION Trigeminal neuralgia is a rare condition that can be effectively treated by carbamazepine or oxcarbazepine but these older drugs are associated with dose-dependent and potentially treatment-limiting adverse effects. Third-generation anticonvulsants, new calcitonin gene-related peptide blockers for migraine, and older drugs such as ketamine and cannabinoids may be promising adjuvants or monotherapeutic options. AREAS COVERED The new drugs, their presumed mechanisms of action, safety and efficacy are discussed herein. There is a paucity of robust clinical evidence in support of these drugs for trigeminal neuralgia. New migraine agents are considered as well although migraines and trigeminal neuralgia are distinct, albeit similar, conditions. No new drugs have been released to market in recent years with the specific indication of trigeminal neuralgia. EXPERT OPINION In real-world clinical practice, about half of trigeminal neuralgia patients take more than one agent for prevention and combination therapy may be the optimal approach. Combination therapy might allow for lower doses of carbamazepine or oxcarbazepine, thus reducing the number and severity of potential adverse events but the potential for pharmacokinetic drug-drug interactions must be considered. Drug therapy for trigeminal neuralgia involves acute or abortive treatments, often administered in hospital versus long-term preventive therapy, usually involving oral agents.
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Affiliation(s)
| | | | - Salah N El-Tallawy
- Anesthesia and Pain Department, King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, Saudi Arabia
- Anesthesia Department, Medicine, Minia University & NCI, Minia, Egypt
| | | | - Rania S Ahmed
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
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2
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Le Franc A, Da Silva A, Lepetre-Mouelhi S. Nanomedicine and voltage-gated sodium channel blockers in pain management: a game changer or a lost cause? Drug Deliv Transl Res 2024:10.1007/s13346-024-01615-9. [PMID: 38861139 DOI: 10.1007/s13346-024-01615-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/25/2024] [Indexed: 06/12/2024]
Abstract
Pain, a complex and debilitating condition affecting millions globally, is a significant concern, especially in the context of post-operative recovery. This comprehensive review explores the complexity of pain and its global impact, emphasizing the modulation of voltage-gated sodium channels (VGSC or NaV channels) as a promising avenue for pain management with the aim of reducing reliance on opioids. The article delves into the role of specific NaV isoforms, particularly NaV 1.7, NaV 1.8, and NaV 1.9, in pain process and discusses the development of sodium channel blockers to target these isoforms precisely. Traditional local anesthetics and selective NaV isoform inhibitors, despite showing varying efficacy in pain management, face challenges in systemic distribution and potential side effects. The review highlights the potential of nanomedicine in improving the delivery of local anesthetics, toxins and selective NaV isoform inhibitors for a targeted and sustained release at the site of pain. This innovative strategy seeks to improve drug bioavailability, minimize systemic exposure, and optimize therapeutic outcomes, holding significant promise for secure pain management and enhancing the quality of life for individuals recovering from surgical procedures or suffering from chronic pain.
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Affiliation(s)
- Adélaïde Le Franc
- Université Paris-Saclay, CNRS, Institut Galien Paris-Saclay, 91400, Orsay, France
| | - Alexandre Da Silva
- Université Paris-Saclay, CNRS, Institut Galien Paris-Saclay, 91400, Orsay, France
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3
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Smith PA. Neuropathic pain; what we know and what we should do about it. FRONTIERS IN PAIN RESEARCH 2023; 4:1220034. [PMID: 37810432 PMCID: PMC10559888 DOI: 10.3389/fpain.2023.1220034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 09/05/2023] [Indexed: 10/10/2023] Open
Abstract
Neuropathic pain can result from injury to, or disease of the nervous system. It is notoriously difficult to treat. Peripheral nerve injury promotes Schwann cell activation and invasion of immunocompetent cells into the site of injury, spinal cord and higher sensory structures such as thalamus and cingulate and sensory cortices. Various cytokines, chemokines, growth factors, monoamines and neuropeptides effect two-way signalling between neurons, glia and immune cells. This promotes sustained hyperexcitability and spontaneous activity in primary afferents that is crucial for onset and persistence of pain as well as misprocessing of sensory information in the spinal cord and supraspinal structures. Much of the current understanding of pain aetiology and identification of drug targets derives from studies of the consequences of peripheral nerve injury in rodent models. Although a vast amount of information has been forthcoming, the translation of this information into the clinical arena has been minimal. Few, if any, major therapeutic approaches have appeared since the mid 1990's. This may reflect failure to recognise differences in pain processing in males vs. females, differences in cellular responses to different types of injury and differences in pain processing in humans vs. animals. Basic science and clinical approaches which seek to bridge this knowledge gap include better assessment of pain in animal models, use of pain models which better emulate human disease, and stratification of human pain phenotypes according to quantitative assessment of signs and symptoms of disease. This can lead to more personalized and effective treatments for individual patients. Significance statement: There is an urgent need to find new treatments for neuropathic pain. Although classical animal models have revealed essential features of pain aetiology such as peripheral and central sensitization and some of the molecular and cellular mechanisms involved, they do not adequately model the multiplicity of disease states or injuries that may bring forth neuropathic pain in the clinic. This review seeks to integrate information from the multiplicity of disciplines that seek to understand neuropathic pain; including immunology, cell biology, electrophysiology and biophysics, anatomy, cell biology, neurology, molecular biology, pharmacology and behavioral science. Beyond this, it underlines ongoing refinements in basic science and clinical practice that will engender improved approaches to pain management.
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Affiliation(s)
- Peter A. Smith
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
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4
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Gomez K, Stratton HJ, Duran P, Loya S, Tang C, Calderon-Rivera A, François-Moutal L, Khanna M, Madura CL, Luo S, McKiver B, Choi E, Ran D, Boinon L, Perez-Miller S, Damaj MI, Moutal A, Khanna R. Identification and targeting of a unique Na V1.7 domain driving chronic pain. Proc Natl Acad Sci U S A 2023; 120:e2217800120. [PMID: 37498871 PMCID: PMC10410761 DOI: 10.1073/pnas.2217800120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 06/27/2023] [Indexed: 07/29/2023] Open
Abstract
Small molecules directly targeting the voltage-gated sodium channel (VGSC) NaV1.7 have not been clinically successful. We reported that preventing the addition of a small ubiquitin-like modifier onto the NaV1.7-interacting cytosolic collapsin response mediator protein 2 (CRMP2) blocked NaV1.7 function and was antinociceptive in rodent models of neuropathic pain. Here, we discovered a CRMP2 regulatory sequence (CRS) unique to NaV1.7 that is essential for this regulatory coupling. CRMP2 preferentially bound to the NaV1.7 CRS over other NaV isoforms. Substitution of the NaV1.7 CRS with the homologous domains from the other eight VGSC isoforms decreased NaV1.7 currents. A cell-penetrant decoy peptide corresponding to the NaV1.7-CRS reduced NaV1.7 currents and trafficking, decreased presynaptic NaV1.7 expression, reduced spinal CGRP release, and reversed nerve injury-induced mechanical allodynia. Importantly, the NaV1.7-CRS peptide did not produce motor impairment, nor did it alter physiological pain sensation, which is essential for survival. As a proof-of-concept for a NaV1.7 -targeted gene therapy, we packaged a plasmid encoding the NaV1.7-CRS in an AAV virus. Treatment with this virus reduced NaV1.7 function in both rodent and rhesus macaque sensory neurons. This gene therapy reversed and prevented mechanical allodynia in a model of nerve injury and reversed mechanical and cold allodynia in a model of chemotherapy-induced peripheral neuropathy. These findings support the conclusion that the CRS domain is a targetable region for the treatment of chronic neuropathic pain.
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Affiliation(s)
- Kimberly Gomez
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY10010
- NYU Pain Research Center, New York, NY10010
| | - Harrison J. Stratton
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ85724
| | - Paz Duran
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY10010
- NYU Pain Research Center, New York, NY10010
| | - Santiago Loya
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY10010
- NYU Pain Research Center, New York, NY10010
| | - Cheng Tang
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY10010
- NYU Pain Research Center, New York, NY10010
| | - Aida Calderon-Rivera
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY10010
- NYU Pain Research Center, New York, NY10010
| | | | - May Khanna
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY10010
- NYU Pain Research Center, New York, NY10010
| | - Cynthia L. Madura
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ85724
| | - Shizhen Luo
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ85724
| | - Bryan McKiver
- Department of Pharmacology and Toxicology and Translational Research Initiative for Pain and Neuropathy, Virginia Commonwealth University, Richmond, VA 23298-0613
| | - Edward Choi
- Department of Pharmacology and Toxicology and Translational Research Initiative for Pain and Neuropathy, Virginia Commonwealth University, Richmond, VA 23298-0613
| | - Dongzhi Ran
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ85724
| | - Lisa Boinon
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ85724
| | - Samantha Perez-Miller
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY10010
- NYU Pain Research Center, New York, NY10010
| | - M. Imad Damaj
- Department of Pharmacology and Toxicology and Translational Research Initiative for Pain and Neuropathy, Virginia Commonwealth University, Richmond, VA 23298-0613
| | - Aubin Moutal
- Department of Pharmacology and Physiology, School of Medicine, St. Louis University, St. Louis, MO63104
| | - Rajesh Khanna
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY10010
- NYU Pain Research Center, New York, NY10010
- Department of Neuroscience and Physiology and Neuroscience Institute, School of Medicine, New York University, New York, NY10010
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Raman S, Ikutame D, Okura K, Matsuka Y. Targeted Therapy for Orofacial Pain: A Novel Perspective for Precision Medicine. J Pers Med 2023; 13:jpm13030565. [PMID: 36983746 PMCID: PMC10057163 DOI: 10.3390/jpm13030565] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/16/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Orofacial pain (OFP) is a dental specialty that includes the diagnosis, management and treatment of disorders of the jaw, mouth, face, head and neck. Evidence-based understanding is critical in effectively treating OFPs as the pathophysiology of these conditions is multifactorial. Since OFP impacts the quality of life of the affected individuals, treating patients successfully is of the utmost significance. Despite the therapeutic choices available, treating OFP is still quite challenging, owing to inter-patient variations. The emerging trends in precision medicine could probably lead us to a paradigm shift in effectively managing the untreatable long-standing pain conditions. Precision medicine is designed based on the patient's genetic profile to meet their needs. Several significant relationships have been discovered based on the genetics and genomics of pain in the past, and some of the notable targets are discussed in this review. The scope of this review is to discuss preclinical and clinical trials that include approaches used in targeted therapy for orofacial pain. Future developments in pain medicine should benefit from current trends in research into novel therapeutic approaches.
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Affiliation(s)
- Swarnalakshmi Raman
- Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
| | - Daisuke Ikutame
- Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
| | - Kazuo Okura
- Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
| | - Yoshizo Matsuka
- Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
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Kitano Y, Shinozuka T. Inhibition of Na V1.7: the possibility of ideal analgesics. RSC Med Chem 2022; 13:895-920. [PMID: 36092147 PMCID: PMC9384491 DOI: 10.1039/d2md00081d] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 07/25/2022] [Indexed: 08/03/2023] Open
Abstract
The selective inhibition of NaV1.7 is a promising strategy for developing novel analgesic agents with fewer adverse effects. Although the potent selective inhibition of NaV1.7 has been recently achieved, multiple NaV1.7 inhibitors failed in clinical development. In this review, the relationship between preclinical in vivo efficacy and NaV1.7 coverage among three types of voltage-gated sodium channel (VGSC) inhibitors, namely conventional VGSC inhibitors, sulphonamides and acyl sulphonamides, is discussed. By demonstrating the PK/PD discrepancy of preclinical studies versus in vivo models and clinical results, the potential reasons behind the disconnect between preclinical results and clinical outcomes are discussed together with strategies for developing ideal analgesic agents.
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Affiliation(s)
- Yutaka Kitano
- R&D Division, Daiichi Sankyo Co., Ltd. 1-2-58 Hiromachi Shinagawa-ku Tokyo 140-8710 Japan
| | - Tsuyoshi Shinozuka
- R&D Division, Daiichi Sankyo Co., Ltd. 1-2-58 Hiromachi Shinagawa-ku Tokyo 140-8710 Japan
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Pergolizzi JV, Gharibo C, Magnusson P, Breve F, LeQuang JA, Varrassi G. Pharmacotherapeutic management of trigeminal neuropathic pain: an update. Expert Opin Pharmacother 2022; 23:1155-1164. [PMID: 35695796 DOI: 10.1080/14656566.2022.2087507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Guidelines recommend a number of pharmacotherapeutic options used as monotherapy or in combination with others for treating the pain of trigeminal neuropathy. AREAS COVERED The authors examine the pharmacotherapeutic options for treating trigeminal neuralgia and supporting evidence in the literature. Guidelines reported the most effective treatment for trigeminal neuropathy, in particular trigeminal neuralgia, appears to be carbamazepine or oxcabazepine, but side effects can be treatment limiting. Lamotrigine and gabapentin are also recommended in guidance. In real-world clinical practice, baclofen, cannabinoids, eslicarbazepine, levetiracetam, brivaracetam, lidocaine, misoprostol, opioids, phenytoin, fosphenytoin, pimozide, sodium valproate, sumatriptan, tizanidine, tocainide, tricyclic antidepressants, and vixotrigine are sometimes used, either as monotherapy or in combination. The relatively small patient population has limited the number of large-scale studies and there is limited evidence on which to base prescribing choices. EXPERT OPINION While there is no optimal pharmacotherapy for treating trigeminal neuropathy, advancements in our understanding of the underlying mechanisms of this condition and drug development indicate promise for NaV inhibitors, despite the fact that not all patients respond to them and they may have potentially treatment-limiting side effects. Nevertheless, better understanding of NaV channels may be important avenues for future drug development for trigeminal neuropathy.
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Affiliation(s)
| | | | - Peter Magnusson
- Centre for Research and Development, Region Gävleborg/Uppsala University, Gävle, Sweden.,Department of Medicine, Cardiology Research Unit, Karolinska Institutet, Stockholm, Sweden
| | - Frank Breve
- Department of Pharmacy Practice, Temple University School of Pharmacy, Philadelphia, Pennsylvania, USA
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8
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Alles SRA, Smith PA. Peripheral Voltage-Gated Cation Channels in Neuropathic Pain and Their Potential as Therapeutic Targets. FRONTIERS IN PAIN RESEARCH 2022; 2:750583. [PMID: 35295464 PMCID: PMC8915663 DOI: 10.3389/fpain.2021.750583] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 11/10/2021] [Indexed: 11/25/2022] Open
Abstract
The persistence of increased excitability and spontaneous activity in injured peripheral neurons is imperative for the development and persistence of many forms of neuropathic pain. This aberrant activity involves increased activity and/or expression of voltage-gated Na+ and Ca2+ channels and hyperpolarization activated cyclic nucleotide gated (HCN) channels as well as decreased function of K+ channels. Because they display limited central side effects, peripherally restricted Na+ and Ca2+ channel blockers and K+ channel activators offer potential therapeutic approaches to pain management. This review outlines the current status and future therapeutic promise of peripherally acting channel modulators. Selective blockers of Nav1.3, Nav1.7, Nav1.8, Cav3.2, and HCN2 and activators of Kv7.2 abrogate signs of neuropathic pain in animal models. Unfortunately, their performance in the clinic has been disappointing; some substances fail to meet therapeutic end points whereas others produce dose-limiting side effects. Despite this, peripheral voltage-gated cation channels retain their promise as therapeutic targets. The way forward may include (i) further structural refinement of K+ channel activators such as retigabine and ASP0819 to improve selectivity and limit toxicity; use or modification of Na+ channel blockers such as vixotrigine, PF-05089771, A803467, PF-01247324, VX-150 or arachnid toxins such as Tap1a; the use of Ca2+ channel blockers such as TTA-P2, TTA-A2, Z 944, ACT709478, and CNCB-2; (ii) improving methods for assessing “pain” as opposed to nociception in rodent models; (iii) recognizing sex differences in pain etiology; (iv) tailoring of therapeutic approaches to meet the symptoms and etiology of pain in individual patients via quantitative sensory testing and other personalized medicine approaches; (v) targeting genetic and biochemical mechanisms controlling channel expression using anti-NGF antibodies such as tanezumab or re-purposed drugs such as vorinostat, a histone methyltransferase inhibitor used in the management of T-cell lymphoma, or cercosporamide a MNK 1/2 inhibitor used in treatment of rheumatoid arthritis; (vi) combination therapy using drugs that are selective for different channel types or regulatory processes; (vii) directing preclinical validation work toward the use of human or human-derived tissue samples; and (viii) application of molecular biological approaches such as clustered regularly interspaced short palindromic repeats (CRISPR) technology.
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Affiliation(s)
- Sascha R A Alles
- Department of Anesthesiology and Critical Care Medicine, University of New Mexico School of Medicine, Albuquerque, NM, United States
| | - Peter A Smith
- Department of Pharmacology, Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
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Jay GW, Barkin RL. Trigeminal neuralgia and persistent idiopathic facial pain (atypical facial pain). Dis Mon 2022; 68:101302. [PMID: 35027171 DOI: 10.1016/j.disamonth.2021.101302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Gary W Jay
- Department of Neurology, Division: Headache/Pain, University of North Carolina, Chapel Hill, USA.
| | - Robert L Barkin
- Departmentts of Anesthesilogy, Family Medicine, Pharrmacology, Rush University Medical College, Chicago Illinois, USA
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Johnson JL, Huang J, Rooney M, Gu C. Optimal pH 8.5 to 9 for the Hydrolysis of Vixotrigine and Other Basic Substrates of Carboxylesterase-1 in Human Liver Microsomes. Xenobiotica 2021; 52:105-112. [PMID: 34904522 DOI: 10.1080/00498254.2021.2018629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Vixotrigine is a voltage- and use-dependent sodium channel blocker under investigation for the potential treatment of neuropathic pain. One of the major in vivo metabolic pathways of vixotrigine in humans is the hydrolysis of the carboxamide to form the carboxylic acid metabolite M14.The in vitro formation of M14 in human hepatocytes was inhibited by the carboxylesterase (CES) inhibitor Bis(4-nitrophenyl) phosphate in a concentration-dependent manner. The hydrolysis reaction was identified to be catalyzed by recombinant human CES1b.Initial observation of only trace level formation of M14 in human liver microsomes at pH 7.4 caused us to doubt the involvement of CES1, an enzyme localized at the endoplasmic reticulum and the dominant carboxylesterase in human liver. Further investigation has revealed that optimal pH for the hydrolysis of vixotrigine and two other basic substrates of CES1, methylphenidate and oseltamivir, in human liver microsomes was pH 8.5 to 9 which is higher than their respective pKa(base), suggesting that neutral form of basic substrates is probably preferred for CES1 catalysis in liver microsomes.
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Affiliation(s)
- Joshua L Johnson
- Drug Metabolism and Pharmacokinetics.,Current affiliation of JLJ: Drug Metabolism and Pharmacokinetics, Takeda, San Diego, CA, USA
| | | | - Michael Rooney
- Clinical Pharmacology and Pharmacometrics, Biogen, Cambridge, MA, USA
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Maarbjerg S, Benoliel R. The changing face of trigeminal neuralgia-A narrative review. Headache 2021; 61:817-837. [PMID: 34214179 DOI: 10.1111/head.14144] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 04/11/2021] [Accepted: 04/21/2021] [Indexed: 12/28/2022]
Abstract
OBJECTIVE This narrative review aims to update the reader on the new classification of trigeminal neuralgia (TN), clinical signs, pathophysiologic evidence, and their implications on management. This review is based on the authors' collective experience and knowledge of the literature in addition to a literature search. BACKGROUND In recent years, the phenotype of TN has been intensively studied leading to discrete groups of patients. These include patients with TN with additional continuous pain, and patients with and without neurovascular compression of the trigeminal dorsal root entry zone. A number of associated clinical signs such as tearing and sensory changes need further research. METHODS The literature on TN was searched in PubMed with the aims of providing evidence for the recently published third edition of the International Classification of Headache Disorders (ICHD) and update the clinical phenotype and management of the TN subcategories. RESULTS The ICHD's new classification for TN is based on reliable clinical data, imaging, and neurophysiologic studies. The TN classification reflects current knowledge and has improved the possibility for clinicians to choose adequate management options. However, there is a lack of effective, safe drugs for the management of TN and sparse, robust data on neurosurgical options. CONCLUSION Research into all aspects of TN-diagnosis, pharmacotherapy, surgery, long-term management prognosis, and natural history-is needed. Research should adhere to the ICHD's schema for TN. Improved drugs are needed along with rigorous research into surgical options and their efficacy for different subtypes of TN.
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Affiliation(s)
- Stine Maarbjerg
- Danish Headache Center, Department of Neurology, Rigshospitalet, Glostrup, Copenhagen, Denmark.,Faculty of Health and Medical Sciences, University of Copenhagen, Glostrup, Copenhagen, Denmark
| | - Rafael Benoliel
- Department of Diagnostic Sciences, Rutgers School of Dental Medicine, Rutgers, The State University of New Jersey, Newark, NJ, USA
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12
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Eagles DA, Chow CY, King GF. Fifteen years of Na
V
1.7 channels as an analgesic target: Why has excellent in vitro pharmacology not translated into in vivo analgesic efficacy? Br J Pharmacol 2020; 179:3592-3611. [DOI: 10.1111/bph.15327] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/14/2020] [Accepted: 10/23/2020] [Indexed: 12/16/2022] Open
Affiliation(s)
- David A. Eagles
- Institute for Molecular Bioscience The University of Queensland St Lucia QLD Australia
| | - Chun Yuen Chow
- Institute for Molecular Bioscience The University of Queensland St Lucia QLD Australia
| | - Glenn F. King
- Institute for Molecular Bioscience The University of Queensland St Lucia QLD Australia
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