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Misra K, Ślęczkowska M, Santoro S, Gerrits MM, Mascia E, Marchi M, Salvi E, Smeets HJM, Hoeijmakers JGJ, Martinelli Boneschi FG, Filippi M, Lauria Pinter G, Faber CG, Esposito F. Broadening the Genetic Spectrum of Painful Small-Fiber Neuropathy through Whole-Exome Study in Early-Onset Cases. Int J Mol Sci 2024; 25:7248. [PMID: 39000354 PMCID: PMC11242789 DOI: 10.3390/ijms25137248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 06/25/2024] [Accepted: 06/28/2024] [Indexed: 07/16/2024] Open
Abstract
Small-Fiber Neuropathy (SFN) is a disorder of the peripheral nervous system, characterised by neuropathic pain; approximately 11% of cases are linked to variants in Voltage-Gated Sodium Channels (VGSCs). This study aims to broaden the genetic knowledge on painful SFN by applying Whole-Exome Sequencing (WES) in Early-Onset (EO) cases. A total of 88 patients from Italy (n = 52) and the Netherlands (n = 36), with a disease onset at age ≤ 45 years old and a Pain Numerical Rating Score ≥ 4, were recruited. After variant filtering and classification, WES analysis identified 142 potentially causative variants in 93 genes; 8 are Pathogenic, 15 are Likely Pathogenic, and 119 are Variants of Uncertain Significance. Notably, an enrichment of variants in transient receptor potential genes was observed, suggesting their role in pain modulation alongside VGSCs. A pathway analysis performed by comparing EO cases with 40 Italian healthy controls found enriched mutated genes in the "Nicotinic acetylcholine receptor signaling pathway". Targeting this pathway with non-opioid drugs could offer novel therapeutic avenues for painful SFN. Additionally, with this study we demonstrated that employing a gene panel of reported mutated genes could serve as an initial screening tool for SFN in genetic studies, enhancing clinical diagnostics.
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Affiliation(s)
- Kaalindi Misra
- Laboratory of Human Genetics of Neurological Disorders, IRCCS San Raffaele Scientific Institute, Institute of Experimental Neurology, 20132 Milan, Italy
| | - Milena Ślęczkowska
- Department of Toxicogenomics, Maastricht University, 6229 ER Maastricht, The Netherlands
- Department of Neurology, Mental Health and Neuroscience Research Intsitute, Maastricht University Medical Centre+, 6229 ER Maastricht, The Netherlands
| | - Silvia Santoro
- Laboratory of Human Genetics of Neurological Disorders, IRCCS San Raffaele Scientific Institute, Institute of Experimental Neurology, 20132 Milan, Italy
| | - Monique M. Gerrits
- Department of Clinical Genetics, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
| | - Elisabetta Mascia
- Laboratory of Human Genetics of Neurological Disorders, IRCCS San Raffaele Scientific Institute, Institute of Experimental Neurology, 20132 Milan, Italy
| | - Margherita Marchi
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy
| | - Erika Salvi
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy
| | - Hubert J. M. Smeets
- Department of Toxicogenomics, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Janneke G. J. Hoeijmakers
- Department of Neurology, Mental Health and Neuroscience Research Intsitute, Maastricht University Medical Centre+, 6229 ER Maastricht, The Netherlands
| | - Filippo Giovanni Martinelli Boneschi
- Aldo Ravelli Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
- Clinical Neurology Unit, Azienda Socio-Sanitaria Territoriale Santi Paolo e Carlo and Department of Health Sciences, University of Milan, 20142 Milan, Italy
| | - Massimo Filippi
- Neurology and Neurorehabilitation Unit, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
- Vita-Salute San Raffaele University, 20132 Milan, Italy
- Neurophysiology Service, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
- Neuroimaging Research Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
| | - Giuseppe Lauria Pinter
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy
- Department of Biomedical and Clinical Sciences “Luigi Sacco”, University of Milan, 20157 Milan, Italy
| | - Catharina G. Faber
- Department of Neurology, Mental Health and Neuroscience Research Intsitute, Maastricht University Medical Centre+, 6229 ER Maastricht, The Netherlands
| | - Federica Esposito
- Laboratory of Human Genetics of Neurological Disorders, IRCCS San Raffaele Scientific Institute, Institute of Experimental Neurology, 20132 Milan, Italy
- Neurology and Neurorehabilitation Unit, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
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Gotti C, Clementi F, Zoli M. Auxiliary protein and chaperone regulation of neuronal nicotinic receptor subtype expression and function. Pharmacol Res 2024; 200:107067. [PMID: 38218358 DOI: 10.1016/j.phrs.2024.107067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Revised: 01/06/2024] [Accepted: 01/08/2024] [Indexed: 01/15/2024]
Abstract
Neuronal nicotinic acetylcholine receptors (nAChRs) are a family of pentameric, ligand-gated ion channels that are located on the surface of neurons and non-neuronal cells and have multiple physiological and pathophysiological functions. In order to reach the cell surface, many nAChR subtypes require the help of chaperone and/or auxiliary/accessory proteins for their assembly, trafficking, pharmacological modulation, and normal functioning in vivo. The use of powerful genome-wide cDNA screening has led to the identification and characterisation of the molecules and mechanisms that participate in the assembly and trafficking of receptor subtypes, including chaperone and auxiliary or accessory proteins. The aim of this review is to describe the latest findings concerning nAChR chaperones and auxiliary proteins and pharmacological chaperones, and how some of them control receptor biogenesis or regulate channel activation and pharmacology. Some auxiliary proteins are subtype selective, some regulate various subtypes, and some not only modulate nAChRs but also target other receptors and signalling pathways. We also discuss how changes in auxiliary proteins may be involved in nAChR dysfunctions.
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Affiliation(s)
- Cecilia Gotti
- CNR, Institute of Neuroscience, Milan, Italy; NeuroMi Milan Center for Neuroscience, University of Milano-Bicocca, Italy.
| | - Francesco Clementi
- CNR, Institute of Neuroscience, Milan, Italy; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Michele Zoli
- Department of Biomedical, Metabolic and Neural Sciences, Center for Neuroscience and Neurotechnology (CfNN), University of Modena and Reggio Emilia, Modena, Italy
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Pei S, Xu C, Tan Y, Wang M, Yu J, Zhangsun D, Zhu X, Luo S. Synthesis, Activity, and Application of Fluorescent Analogs of [D1G, Δ14Q]LvIC Targeting α6β4 Nicotinic Acetylcholine Receptor. Bioconjug Chem 2023; 34:2194-2204. [PMID: 37748043 DOI: 10.1021/acs.bioconjchem.3c00283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/27/2023]
Abstract
α6β4* nicotinic acetylcholine receptor (nAChR) (* represents the possible presence of additional subunits) is mainly distributed in the central and peripheral nervous system and is associated with neurological diseases, such as neuropathic pain; however, the ability to explore its function and distribution is limited due to the lack of pharmacological tools. As one of the analogs of α-conotoxin (α-CTx) LvIC from Conus lividus, [D1G, Δ14Q]LvIC (Lv) selectively and potently blocks α6/α3β4 nAChR (α6/α3 represents a chimera). Here, we synthesized three fluorescent analogs of Lv by connecting fluorescent molecules 6-carboxytetramethylrhodamine succinimidyl ester (6-TAMRA-SE, R), Cy3 NHS ester (Cy3, C) and BODIPY-FL NHS ester (BDP, B) to the N-terminus of the peptide and obtained Lv-R, Lv-C, and Lv-B, respectively. The potency and selectivity of three fluorescent peptides were evaluated using two-electrode voltage-clamp recording on nAChR subtypes expressed in Xenopus laevis oocytes, and the potency and selectivity of Lv-B were almost maintained with the half-maximal inhibition (IC50) of 64 nM. Then, we explored the stability of Lv-B in artificial cerebrospinal fluid and stained rat brain slices with Lv-B. The results indicated that the stability of Lv-B was slightly improved compared to that of native Lv. Additionally, we detected the distribution of the α6β4* nAChR subtype in the cerebral cortex using green fluorescently labeled peptide and fluorescence microscopy. Our findings not only provide a visualized pharmacological tool for exploring the distribution of the α6β4* nAChR subtype in various situ tissues and organs but also extend the application of α-CTx [D1G, Δ14Q]LvIC to demonstrate the involvement of α6β4 nAChR function in pathophysiology and pharmacology.
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Affiliation(s)
- Shengrong Pei
- Guangxi Key Laboratory of Special Biomedicine; School of Medicine, Guangxi University, Nanning 530004, China
| | - Chenxing Xu
- Guangxi Key Laboratory of Special Biomedicine; School of Medicine, Guangxi University, Nanning 530004, China
| | - Yao Tan
- Guangxi Key Laboratory of Special Biomedicine; School of Medicine, Guangxi University, Nanning 530004, China
| | - Meiting Wang
- Guangxi Key Laboratory of Special Biomedicine; School of Medicine, Guangxi University, Nanning 530004, China
| | - Jinpeng Yu
- Guangxi Key Laboratory of Special Biomedicine; School of Medicine, Guangxi University, Nanning 530004, China
| | - Dongting Zhangsun
- Guangxi Key Laboratory of Special Biomedicine; School of Medicine, Guangxi University, Nanning 530004, China
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Hainan University, Haikou 570228, China
| | - Xiaopeng Zhu
- Guangxi Key Laboratory of Special Biomedicine; School of Medicine, Guangxi University, Nanning 530004, China
| | - Sulan Luo
- Guangxi Key Laboratory of Special Biomedicine; School of Medicine, Guangxi University, Nanning 530004, China
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Hainan University, Haikou 570228, China
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Montigné E, Balayssac D. Exploring Cholinergic Compounds for Peripheral Neuropathic Pain Management: A Comprehensive Scoping Review of Rodent Model Studies. Pharmaceuticals (Basel) 2023; 16:1363. [PMID: 37895835 PMCID: PMC10609809 DOI: 10.3390/ph16101363] [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: 08/02/2023] [Revised: 09/01/2023] [Accepted: 09/14/2023] [Indexed: 10/29/2023] Open
Abstract
Neuropathic pain affects about 7-8% of the population, and its management still poses challenges with unmet needs. Over the past decades, researchers have explored the cholinergic system (muscarinic and nicotinic acetylcholine receptors: mAChR and nAChR) and compounds targeting these receptors as potential analgesics for neuropathic pain management. This scoping review aims to provide an overview of studies on peripheral neuropathic pain (PNP) in rodent models, exploring compounds targeting cholinergic neurotransmission. The inclusion criteria were original articles on PNP in rodent models that explored the use of compounds directly targeting cholinergic neurotransmission and reported results of nociceptive behavioral assays. The literature search was performed in the PubMed and Web of Science databases (1 January 2000-22 April 2023). The selection process yielded 82 publications, encompassing 62 compounds. The most studied compounds were agonists of α4β2 nAChR and α7 nAChR, and antagonists of α9/α10 nAChR, along with those increasing acetylcholine and targeting mAChRs. Studies mainly reported antinociceptive effects in traumatic PNP models, and to a lesser extent, chemotherapy-induced neuropathy or diabetic models. These preclinical studies underscore the considerable potential of cholinergic compounds in the management of PNP, warranting the initiation of clinical trials.
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Affiliation(s)
- Edouard Montigné
- INSERM, U1107, NEURO-DOL, Université Clermont Auvergne, F-63000 Clermont-Ferrand, France;
| | - David Balayssac
- INSERM, U1107, NEURO-DOL, Université Clermont Auvergne, Direction de la Recherche Clinique et de l’Innovation, CHU Clermont-Ferrand, F-63000 Clermont-Ferrand, France
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5
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Vallés AS, Barrantes FJ. Nicotinic Acetylcholine Receptor Dysfunction in Addiction and in Some Neurodegenerative and Neuropsychiatric Diseases. Cells 2023; 12:2051. [PMID: 37626860 PMCID: PMC10453526 DOI: 10.3390/cells12162051] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/20/2023] [Accepted: 08/10/2023] [Indexed: 08/27/2023] Open
Abstract
The cholinergic system plays an essential role in brain development, physiology, and pathophysiology. Herein, we review how specific alterations in this system, through genetic mutations or abnormal receptor function, can lead to aberrant neural circuitry that triggers disease. The review focuses on the nicotinic acetylcholine receptor (nAChR) and its role in addiction and in neurodegenerative and neuropsychiatric diseases and epilepsy. Cholinergic dysfunction is associated with inflammatory processes mainly through the involvement of α7 nAChRs expressed in brain and in peripheral immune cells. Evidence suggests that these neuroinflammatory processes trigger and aggravate pathological states. We discuss the preclinical evidence demonstrating the therapeutic potential of nAChR ligands in Alzheimer disease, Parkinson disease, schizophrenia spectrum disorders, and in autosomal dominant sleep-related hypermotor epilepsy. PubMed and Google Scholar bibliographic databases were searched with the keywords indicated below.
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Affiliation(s)
- Ana Sofía Vallés
- Bahía Blanca Institute of Biochemical Research (UNS-CONICET), Bahía Blanca 8000, Argentina;
| | - Francisco J. Barrantes
- Biomedical Research Institute (BIOMED), Faculty of Medical Sciences, Pontifical Catholic University of Argentina—National Scientific and Technical Research Council, Av. Alicia Moreau de Justo 1600, Buenos Aires C1107AFF, Argentina
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6
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Gu YJ, Qian HY, Zhou F, Zhang L, Chen L, Song Y, Chen YN, Zhang HL. Folic acid relieves bone cancer pain by downregulating P2X2/3 receptors in rats. Brain Res 2023; 1811:148405. [PMID: 37164174 DOI: 10.1016/j.brainres.2023.148405] [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: 12/27/2022] [Revised: 05/04/2023] [Accepted: 05/06/2023] [Indexed: 05/12/2023]
Abstract
BACKGROUND Bone cancer pain (BCP) remains a clinical challenge due to the limited and side effects of therapeutic methods. Folic acid has been known as an FDA approved dietary supplement and proved to have an analgesic effect in neuropathic pain. Here we investigate the role and mechanism of folic acid in bone cancer pain of a rat model. METHODS Walker 256 tumor cells were inoculated into the left tibia of rats to induce bone cancer pain model. Pain reflex were assessed by paw withdrawal threshold (PWT) response to Von Frey filaments and paw withdrawal latency (PWL) response to thermal stimulation. Folic acid was injected intraperitoneally to evaluate its analgesic effect in rats with bone cancer pain. Western blotting and qPCR were used to determine P2X2/3 receptor protein and mRNA levels in ipsilateral L4-6 dorsal root ganglion (DRG) and spinal dorsal horn (SDH). RESULTS The PWT and PWL of rats with bone cancer pain were obviously decreased compared to the naïve and sham rats. Interestingly, continuous folic acid treatment significantly increased the PWT and PWL of rats with bone cancer pain. P2X2 and P2X3 receptors were clearly upregulated at both mRNA and protein expression in L4-6 DRG and SDH of rats with bone cancer pain. P2X2 and P2X3 receptors were mainly localized with CGRP (calcitonin gene-related peptide) or IB4 (isolectin B4) positive neurons in L4-6 DRG of rats with bone cancer pain. Notably, continuous folic acid treatment significantly reduced the expression of P2X2 and P2X3 receptors in L4-6 DRG and SDH of rats with bone cancer pain. Finally, intrathecal injection of A317491 (a selective antagonist of P2X2/3 receptors) markedly elevated the PWT and PWL of rats with bone cancer pain. CONCLUSION These results suggest that folic acid has an effective antinociceptive effect on bone cancer pain, which is mediated by downregulating P2X2/3 receptors in L4-6 DRG and SDH of rats with bone cancer pain. Folic acid may be a novel therapeutic strategy in cancer patients for pain relief.
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Affiliation(s)
- Yong-Juan Gu
- Center for Translational Medicine, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China; Department of Oncology, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China
| | - He-Ya Qian
- Center for Translational Medicine, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China; Department of Oncology, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China
| | - Fang Zhou
- Center for Translational Medicine, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China; Department of Oncology, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China
| | - Ling Zhang
- Center for Translational Medicine, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China
| | - Long Chen
- Center for Translational Medicine, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China
| | - Yu Song
- Department of Oncology, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China
| | - Ya-Nan Chen
- Department of Oncology, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China.
| | - Hai-Long Zhang
- Center for Translational Medicine, Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang 215600, China; Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou 215123, China.
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7
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Dong J, Zhang P, Xie J, Xie T, Zhu X, Zhangsun D, Yu J, Luo S. Loop2 Size Modification Reveals Significant Impacts on the Potency of α-Conotoxin TxID. Mar Drugs 2023; 21:md21050286. [PMID: 37233480 DOI: 10.3390/md21050286] [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: 04/05/2023] [Revised: 04/27/2023] [Accepted: 04/29/2023] [Indexed: 05/27/2023] Open
Abstract
α4/6-conotoxin TxID, which was identified from Conus textile, simultaneously blocks rat (r) α3β4 and rα6/α3β4 nicotinic acetylcholine receptors (nAChRs) with IC50 values of 3.6 nM and 33.9 nM, respectively. In order to identify the effects of loop2 size on the potency of TxID, alanine (Ala) insertion and truncation mutants were designed and synthesized in this study. An electrophysiological assay was used to evaluate the activity of TxID and its loop2-modified mutants. The results showed that the inhibition of 4/7-subfamily mutants [+9A]TxID, [+10A]TxID, [+14A]TxID, and all the 4/5-subfamily mutants against rα3β4 and rα6/α3β4 nAChRs decreased. Overall, ala-insertion or truncation of the 9th, 10th, and 11th amino acid results in a loss of inhibition and the truncation of loop2 has more obvious impacts on its functions. Our findings have strengthened the understanding of α-conotoxin, provided guidance for further modifications, and offered a perspective for future studies on the molecular mechanism of the interaction between α-conotoxins and nAChRs.
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Affiliation(s)
- Jianying Dong
- School of Medicine, Guangxi University, Nanning 530004, China
| | - Panpan Zhang
- School of Medicine, Guangxi University, Nanning 530004, China
| | - Junjie Xie
- School of Medicine, Guangxi University, Nanning 530004, China
| | - Ting Xie
- School of Medicine, Guangxi University, Nanning 530004, China
| | - Xiaopeng Zhu
- School of Medicine, Guangxi University, Nanning 530004, China
| | - Dongting Zhangsun
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Laboratory for Marine Drugs of Haikou, Hainan University, Haikou 570228, China
| | - Jinpeng Yu
- School of Medicine, Guangxi University, Nanning 530004, China
| | - Sulan Luo
- School of Medicine, Guangxi University, Nanning 530004, China
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Laboratory for Marine Drugs of Haikou, Hainan University, Haikou 570228, China
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8
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Walker NB, Yan Y, Tapia MA, Tucker BR, Thomas LN, George BE, West AM, Marotta CB, Lester HA, Dougherty DA, Holleran KM, Jones SR, Drenan RM. β2 nAChR Activation on VTA DA Neurons Is Sufficient for Nicotine Reinforcement in Rats. eNeuro 2023; 10:ENEURO.0449-22.2023. [PMID: 37193602 PMCID: PMC10216253 DOI: 10.1523/eneuro.0449-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 05/01/2023] [Accepted: 05/08/2023] [Indexed: 05/18/2023] Open
Abstract
Mesolimbic nicotinic acetylcholine receptor (nAChRs) activation is necessary for nicotine reinforcement behavior, but it is unknown whether selective activation of nAChRs in the dopamine (DA) reward pathway is sufficient to support nicotine reinforcement. In this study, we tested the hypothesis that activation of β2-containing (β2*) nAChRs on VTA neurons is sufficient for intravenous nicotine self-administration (SA). We expressed β2 nAChR subunits with enhanced sensitivity to nicotine (referred to as β2Leu9'Ser) in the VTA of male Sprague Dawley (SD) rats, enabling very low concentrations of nicotine to selectively activate β2* nAChRs on transduced neurons. Rats expressing β2Leu9'Ser subunits acquired nicotine SA at 1.5 μg/kg/infusion, a dose too low to support acquisition in control rats. Saline substitution extinguished responding for 1.5 μg/kg/inf, verifying that this dose was reinforcing. β2Leu9'Ser nAChRs also supported acquisition at the typical training dose in rats (30 μg/kg/inf) and reducing the dose to 1.5 μg/kg/inf caused a significant increase in the rate of nicotine SA. Viral expression of β2Leu9'Ser subunits only in VTA DA neurons (via TH-Cre rats) also enabled acquisition of nicotine SA at 1.5 μg/kg/inf, and saline substitution significantly attenuated responding. Next, we examined electrically-evoked DA release in slices from β2Leu9'Ser rats with a history of nicotine SA. Single-pulse evoked DA release and DA uptake rate were reduced in β2Leu9'Ser NAc slices, but relative increases in DA following a train of stimuli were preserved. These results are the first to report that β2* nAChR activation on VTA neurons is sufficient for nicotine reinforcement in rats.
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Affiliation(s)
- Noah B Walker
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
| | - Yijin Yan
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
| | - Melissa A Tapia
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
| | - Brenton R Tucker
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
| | - Leanne N Thomas
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
| | - Brianna E George
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
| | - Alyssa M West
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
| | - Christopher B Marotta
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91106
| | - Henry A Lester
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91106
| | - Dennis A Dougherty
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91106
| | - Katherine M Holleran
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
| | - Sara R Jones
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
| | - Ryan M Drenan
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157
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9
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Tae HS, Adams DJ. Nicotinic acetylcholine receptor subtype expression, function, and pharmacology: Therapeutic potential of α-conotoxins. Pharmacol Res 2023; 191:106747. [PMID: 37001708 DOI: 10.1016/j.phrs.2023.106747] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/22/2023] [Accepted: 03/27/2023] [Indexed: 04/03/2023]
Abstract
The pentameric nicotinic acetylcholine receptors (nAChRs) are typically classed as muscle- or neuronal-type, however, the latter has also been reported in non-neuronal cells. Given their broad distribution, nAChRs mediate numerous physiological and pathological processes including synaptic transmission, presynaptic modulation of transmitter release, neuropathic pain, inflammation, and cancer. There are 17 different nAChR subunits and combinations of these subunits produce subtypes with diverse pharmacological properties. The expression and role of some nAChR subtypes have been extensively deciphered with the aid of knock-out models. Many nAChR subtypes expressed in heterologous systems are selectively targeted by the disulfide-rich α-conotoxins. α-Conotoxins are small peptides isolated from the venom of cone snails, and a number of them have potential pharmaceutical value.
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10
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Hayot G, Massonot M, Keime C, Faure E, Golzio C. Loss of autism-candidate CHD8 perturbs neural crest development and intestinal homeostatic balance. Life Sci Alliance 2022; 6:6/1/e202201456. [PMID: 36375841 PMCID: PMC9664244 DOI: 10.26508/lsa.202201456] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 10/19/2022] [Accepted: 10/21/2022] [Indexed: 11/16/2022] Open
Abstract
Individuals with mutations in CHD8 present with gastrointestinal complaints, yet the underlying mechanisms are understudied. Here, using a stable constitutive chd8 mutant zebrafish model, we found that the loss of chd8 leads to a reduced number of vagal neural crest cells (NCCs), enteric neural and glial progenitors, emigrating from the neural tube, and that their early migration capability was altered. At later stages, although the intestinal colonization by NCCs was complete, we found the decreased numbers of both serotonin-producing enterochromaffin cells and NCC-derived serotonergic neurons, suggesting an intestinal hyposerotonemia in the absence of chd8 Furthermore, transcriptomic analyses revealed an altered expression of key receptors and enzymes in serotonin and acetylcholine signaling pathways. The tissue examination of chd8 mutants revealed a thinner intestinal epithelium accompanied by an accumulation of neutrophils and the decreased numbers of goblet cells and eosinophils. Last, single-cell sequencing of whole intestines showed a global disruption of the immune balance with a perturbed expression of inflammatory interleukins and changes in immune cell clusters. Our findings propose a causal developmental link between chd8, NCC development, intestinal homeostasis, and autism-associated gastrointestinal complaints.
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Affiliation(s)
- Gaëlle Hayot
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France,Centre National de la Recherche Scientifique, Illkirch, France,Institut National de la Santé et de la Recherche Médicale, Illkirch, France,Université de Strasbourg, Strasbourg, France
| | - Mathieu Massonot
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France,Centre National de la Recherche Scientifique, Illkirch, France,Institut National de la Santé et de la Recherche Médicale, Illkirch, France,Université de Strasbourg, Strasbourg, France
| | - Céline Keime
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France,Centre National de la Recherche Scientifique, Illkirch, France,Institut National de la Santé et de la Recherche Médicale, Illkirch, France,Université de Strasbourg, Strasbourg, France
| | - Elodie Faure
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France,Centre National de la Recherche Scientifique, Illkirch, France,Institut National de la Santé et de la Recherche Médicale, Illkirch, France,Université de Strasbourg, Strasbourg, France
| | - Christelle Golzio
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France .,Centre National de la Recherche Scientifique, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, Illkirch, France.,Université de Strasbourg, Strasbourg, France
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11
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Latragna A, Sabaté San José A, Tsimpos P, Vermeiren S, Gualdani R, Chakrabarti S, Callejo G, Desiderio S, Shomroni O, Sitte M, Kricha S, Luypaert M, Vanhollebeke B, Laumet G, Salinas G, Smith ESJ, Ris L, Bellefroid EJ. Prdm12 modulates pain-related behavior by remodeling gene expression in mature nociceptors. Pain 2022; 163:e927-e941. [PMID: 34961757 PMCID: PMC9341233 DOI: 10.1097/j.pain.0000000000002536] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 10/29/2021] [Accepted: 11/03/2021] [Indexed: 11/26/2022]
Abstract
ABSTRACT Prdm12 is a conserved epigenetic transcriptional regulator that displays restricted expression in nociceptors of the developing peripheral nervous system. In mice, Prdm12 is required for the development of the entire nociceptive lineage. In humans, PRDM12 mutations cause congenital insensitivity to pain, likely because of the loss of nociceptors. Prdm12 expression is maintained in mature nociceptors suggesting a yet-to-be explored functional role in adults. Using Prdm12 inducible conditional knockout mouse models, we report that in adult nociceptors Prdm12 is no longer required for cell survival but continues to play a role in the transcriptional control of a network of genes, many of them encoding ion channels and receptors. We found that disruption of Prdm12 alters the excitability of dorsal root ganglion neurons in culture. Phenotypically, we observed that mice lacking Prdm12 exhibit normal responses to thermal and mechanical nociceptive stimuli but a reduced response to capsaicin and hypersensitivity to formalin-induced inflammatory pain. Together, our data indicate that Prdm12 regulates pain-related behavior in a complex way by modulating gene expression in adult nociceptors and controlling their excitability. The results encourage further studies to assess the potential of Prdm12 as a target for analgesic development.
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Affiliation(s)
- Aurore Latragna
- ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Gosselies, Belgium
- Laboratory of Neuroscience, UMONS Research Institute for Health Sciences and Technology, University of Mons, Mons, Belgium
| | - Alba Sabaté San José
- ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Gosselies, Belgium
| | - Panagiotis Tsimpos
- ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Gosselies, Belgium
| | - Simon Vermeiren
- ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Gosselies, Belgium
| | - Roberta Gualdani
- Laboratory of Neuroscience, UMONS Research Institute for Health Sciences and Technology, University of Mons, Mons, Belgium
| | | | - Gerard Callejo
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | - Simon Desiderio
- ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Gosselies, Belgium
| | - Orr Shomroni
- NGS Integrative Genomics, Department of Human Genetics at the University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Maren Sitte
- NGS Integrative Genomics, Department of Human Genetics at the University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Sadia Kricha
- ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Gosselies, Belgium
| | - Maëlle Luypaert
- ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Gosselies, Belgium
| | - Benoit Vanhollebeke
- ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Gosselies, Belgium
| | - Geoffroy Laumet
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Gabriela Salinas
- NGS Integrative Genomics, Department of Human Genetics at the University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Ewan St. John Smith
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | - Laurence Ris
- Laboratory of Neuroscience, UMONS Research Institute for Health Sciences and Technology, University of Mons, Mons, Belgium
| | - Eric J. Bellefroid
- ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Gosselies, Belgium
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12
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A Novel α4/7-Conotoxin QuIA Selectively Inhibits α3β2 and α6/α3β4 Nicotinic Acetylcholine Receptor Subtypes with High Efficacy. Mar Drugs 2022; 20:md20020146. [PMID: 35200675 PMCID: PMC8878501 DOI: 10.3390/md20020146] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 02/07/2022] [Accepted: 02/14/2022] [Indexed: 12/10/2022] Open
Abstract
α6β4 nAChR is expressed in the peripheral and central nervous systems and is associated with pain, addiction, and movement disorders. Natural α-conotoxins (α-CTxs) can effectively block different nAChR subtypes with higher efficacy and selectivity. However, the research on α6β4 nAChR is relatively poor, partly because of the lack of available target-specific α-CTxs. In this study, we synthesized a novel α-4/7 conotoxin QuIA that was found from Conus quercinus. We investigated the efficacy of this peptide to different nAChR subtypes using a two-electrode voltage-clamp technique. Remarkably, we found α-QuIA inhibited the neuronal α3β2 and α6/α3β4 nAChR subtypes with significantly high affinity (IC50 was 55.7 nM and 90.68 nM, respectively), and did not block other nAChR subtypes even at a high concentration of 10 μM. In contrast, most α-CTxs have been determined so far to effectively block the α6/α3β4 nAChR subtype while also maintaining a similar higher efficacy against the closely related α6β2β3 and/or α3β4 subtypes, which are different from QuIA. In conclusion, α-QuIA is a novel α4/7-CTx, which has the potential to develop as an effective neuropharmacology tool to detect the function of α6β4 nAChR.
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13
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Carreño D, Lotfipour S. Sex- and genotype-dependent nicotine plus cue-primed reinstatement is enhanced in adolescent Sprague Dawley rats containing the human CHRNA6 3'-UTR polymorphism (rs2304297). Front Psychiatry 2022; 13:1064211. [PMID: 36704741 PMCID: PMC9872558 DOI: 10.3389/fpsyt.2022.1064211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 12/21/2022] [Indexed: 01/11/2023] Open
Abstract
RATIONALE Large-scale human candidate gene studies have indicated that a genetic variant (rs2304297) in the alpha(α)6 nicotinic acetylcholine receptor (nAChR) subunit, encoded by the CHRNA6 gene, may play a key role in adolescent nicotine addictive behavior. We hypothesized that the polymorphism selectively enhances nicotine + cue-primed reinstatement, but not nicotine- or cue-reinstatement in α6 GG (risk) vs. α6 CC (non-risk) allele carriers, without having baseline effects on natural rewards. METHODS Using CRISPR-Cas9 genomic engineering, we developed a humanized rat line with the human gene variant of the CHRNA6 3'-UTR C 123 G polymorphism in Sprague-Dawley rats. Genetically modified adolescent male and female rats were food trained under a fixed-ratio (FR)1 schedule of reinforcement and progressively increased to FR5. Animals were implanted with catheters and began nicotine self-administration (15 μg/kg/infusion) at FR5. Upon reaching stable responding, reinforced behavior was extinguished by removal of drug and cues. Reinstatement testing began for cue only, nicotine only, and nicotine + cue in a Latin Square Design. Animals were returned to extinction conditions for 2 days minimum between testing. RESULTS For natural food rewards, nicotine self-administration, progressive ratio, and extinction, adolescent male and female (α6 GG and α6 CC ) rats exhibited equivalent behaviors. Male α6 GG rats show enhanced nicotine + cue-primed reinstatement when compared with male α6 CC rats. This genotype effect on reinstatement was not seen in female rats. CONCLUSION Our findings support the in vivo functional role of the human CHRNA6 3'-UTR SNP genetic variant in sex-dependently enhancing nicotine seeking behavior in adolescent rats. Overall, the findings support clinical and preclinical data highlighting a role of α6 nAChRs mediating sex heterogeneity in substance use and related phenotypes.
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Affiliation(s)
- Diana Carreño
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, CA, United States
| | - Shahrdad Lotfipour
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, CA, United States.,Department of Pathology and Laboratory Medicine, University of California, Irvine, Irvine, CA, United States.,Department of Emergency Medicine, University of California, Irvine, Irvine, CA, United States
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14
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Matta JA, Gu S, Davini WB, Bredt DS. Nicotinic acetylcholine receptor redux: Discovery of accessories opens therapeutic vistas. Science 2021; 373:373/6556/eabg6539. [PMID: 34385370 DOI: 10.1126/science.abg6539] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The neurotransmitter acetylcholine (ACh) acts in part through a family of nicotinic ACh receptors (nAChRs), which mediate diverse physiological processes including muscle contraction, neurotransmission, and sensory transduction. Pharmacologically, nAChRs are responsible for tobacco addiction and are targeted by medicines for hypertension and dementia. Nicotinic AChRs were the first ion channels to be isolated. Recent studies have identified molecules that control nAChR biogenesis, trafficking, and function. These nAChR accessories include protein and chemical chaperones as well as auxiliary subunits. Whereas some factors act on many nAChRs, others are receptor specific. Discovery of these regulatory mechanisms is transforming nAChR research in cells and tissues ranging from central neurons to spinal ganglia to cochlear hair cells. Nicotinic AChR-specific accessories also enable drug discovery on high-confidence targets for psychiatric, neurological, and auditory disorders.
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Affiliation(s)
| | | | - Weston B Davini
- Neuroscience Discovery, Janssen Pharmaceutical Companies of Johnson & Johnson, San Diego, CA 92121, USA
| | - David S Bredt
- Neuroscience Discovery, Janssen Pharmaceutical Companies of Johnson & Johnson, San Diego, CA 92121, USA.
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15
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Abstract
Pain is an immense clinical and societal challenge, and the key to understanding and treating it is variability. Robust interindividual differences are consistently observed in pain sensitivity, susceptibility to developing painful disorders, and response to analgesic manipulations. This review examines the causes of this variability, including both organismic and environmental sources. Chronic pain development is a textbook example of a gene-environment interaction, requiring both chance initiating events (e.g., trauma, infection) and more immutable risk factors. The focus is on genetic factors, since twin studies have determined that a plurality of the variance likely derives from inherited genetic variants, but sex, age, ethnicity, personality variables, and environmental factors are also considered.
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Affiliation(s)
- Jeffrey S Mogil
- Departments of Psychology and Anesthesia, Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada;
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16
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Dhanasobhon D, Medrano MC, Becker LJ, Moreno-Lopez Y, Kavraal S, Bichara C, Schlichter R, Inquimbert P, Yalcin I, Cordero-Erausquin M. Enhanced analgesic cholinergic tone in the spinal cord in a mouse model of neuropathic pain. Neurobiol Dis 2021; 155:105363. [PMID: 33845128 DOI: 10.1016/j.nbd.2021.105363] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 03/12/2021] [Accepted: 03/31/2021] [Indexed: 11/30/2022] Open
Abstract
Endogenous acetylcholine (ACh) is an important modulator of nociceptive sensory processing in the spinal cord. An increased level of spinal ACh induces analgesia both in humans and rodents while interfering with cholinergic signaling is allodynic, demonstrating that a basal tone of spinal ACh modulates nociceptive responses in naïve animals. The plasticity undergone by this cholinergic system in chronic pain situation is unknown, and the mere presence of this tone in neuropathic animals is controversial. We have addressed these issues in mice through behavioral experiments, histology, electrophysiology and molecular biology, in the cuff model of peripheral neuropathy. Our behavior experiments demonstrate the persistence, and even increased impact of the analgesic cholinergic tone acting through nicotinic receptors in cuff animals. The neuropathy does not affect the number or membrane properties of dorsal horn cholinergic neurons, nor specifically the frequency of their synaptic inputs. The alterations thus appear to be in the neurons receiving the cholinergic signaling, which is confirmed by the fact that subthreshold doses of acetylcholinesterase (AChE) inhibitors in sham animals become anti-allodynic in cuff mice and by the altered expression of the β2 nicotinic receptor subunit. Our results demonstrate that endogenous cholinergic signaling can be manipulated to relieve mechanical allodynia in animal models of peripheral neuropathy. Until now, AChE inhibitors have mainly been used in the clinics in situations of acute pain (parturition, post-operative). The fact that lower doses (thus with fewer side effects) could be efficient in chronic pain conditions opens new avenues for the treatment of neuropathic pain. SIGNIFICANCE STATEMENT: Chronic pain continues to be the most common cause of disability that impairs the quality of life, accruing enormous and escalating socio-economic costs. A better understanding of the plasticity of spinal neuronal networks, crucially involved in nociceptive processing, could help designing new therapeutic avenues. We here demonstrate that chronic pain modifies the spinal nociceptive network in such a way that it becomes more sensitive to cholinergic modulations. The spinal cholinergic system is responsible for an analgesic tone that can be exacerbated by acetylcholinesterase inhibitors, a property used in the clinic to relief acute pain (child birth, post-op). Our results suggest that lower doses of acetylcholinesterases, with even fewer side effects, could be efficient to relieve chronic pain.
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Affiliation(s)
- Dhanasak Dhanasobhon
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Maria-Carmen Medrano
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Léa J Becker
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Yunuen Moreno-Lopez
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Sehrazat Kavraal
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Charlotte Bichara
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Rémy Schlichter
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Perrine Inquimbert
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Ipek Yalcin
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - Matilde Cordero-Erausquin
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France; University of Strasbourg Institute for Advanced Study (USIAS), 67000 Strasbourg, France.
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17
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Landy MA, Goyal M, Casey KM, Liu C, Lai HC. Loss of Prdm12 during development, but not in mature nociceptors, causes defects in pain sensation. Cell Rep 2021; 34:108913. [PMID: 33789102 PMCID: PMC8048104 DOI: 10.1016/j.celrep.2021.108913] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 02/11/2021] [Accepted: 03/05/2021] [Indexed: 12/30/2022] Open
Abstract
Prdm12 is a key transcription factor in nociceptor neurogenesis. Mutations of Prdm12 cause congenital insensitivity to pain (CIP) from failure of nociceptor development. However, precisely how deletion of Prdm12 during development or adulthood affects nociception is unknown. Here, we employ tissue- and temporal-specific knockout mouse models to test the function of Prdm12 during development and in adulthood. We find that constitutive loss of Prdm12 causes deficiencies in proliferation during sensory neurogenesis. We also demonstrate that conditional knockout from dorsal root ganglia (DRGs) during embryogenesis causes defects in nociception. In contrast, we find that, in adult DRGs, Prdm12 is dispensable for most pain-sensation and injury-induced hypersensitivity. Using transcriptomic analysis, we find mostly unique changes in adult Prdm12 knockout DRGs compared with embryonic knockout and that PRDM12 is likely a transcriptional activator in the adult. Overall, we find that the function of PRDM12 changes over developmental time.
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Affiliation(s)
- Mark A Landy
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Megan Goyal
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Katherine M Casey
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Chen Liu
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390, USA; Department of Internal Medicine, Hypothalamic Research Center, Dallas, TX 75390, USA
| | - Helen C Lai
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390, USA.
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18
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Quantitative differences in neuronal subpopulations between mouse and human dorsal root ganglia demonstrated with RNAscope in situ hybridization. Pain 2021; 161:2410-2424. [PMID: 32639368 DOI: 10.1097/j.pain.0000000000001973] [Citation(s) in RCA: 109] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Next-generation transcriptomics in combination with imaging-based approaches have emerged as powerful tools for the characterization of dorsal root ganglion (DRG) neuronal subpopulations. The mouse DRG has been well characterized by many independently conducted studies with convergent findings, but few studies have directly compared expression of population markers between mouse and human. This is important because of our increasing reliance on the mouse as a preclinical model for translational studies. Although calcitonin gene-related peptide (CGRP) and P2X purinergic ion channel type 3 receptor (P2X3R) have been used to define peptidergic and nonpeptidergic nociceptor subpopulations, respectively, in mouse DRG, these populations may be different in other species. To directly test this, as well as a host of other markers, we used multiplex RNAscope in situ hybridization to elucidate the distribution of a multitude of unique and classic neuronal mRNAs in peptidergic (CGRP-expressing) and nonpeptidergic (P2X3R-expressing) nociceptor subpopulations in mouse and human DRG. We found a large overlapping CGRP and P2X3R neuronal subpopulation in human, lumbar DRG that was not present in mouse. We also found differential expression in a variety of mRNAs for transient receptor potential channels, cholinergic receptors, potassium channels, sodium channels, and other markers/targets. These data offer insights into the spatial and functional organization of neuronal cell subpopulations in the rodent and human DRG and support the idea that sensory system organizational principles are likely different between both species.
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19
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Knowland D, Gu S, Eckert WA, Dawe GB, Matta JA, Limberis J, Wickenden AD, Bhattacharya A, Bredt DS. Functional α6β4 acetylcholine receptor expression enables pharmacological testing of nicotinic agonists with analgesic properties. J Clin Invest 2021; 130:6158-6170. [PMID: 33074244 DOI: 10.1172/jci140311] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/06/2020] [Indexed: 01/25/2023] Open
Abstract
The α6β4 nicotinic acetylcholine receptor (nAChR) is enriched in dorsal root ganglia neurons and is an attractive non-opioid therapeutic target for pain. However, difficulty expressing human α6β4 receptors in recombinant systems has precluded drug discovery. Here, genome-wide screening identified accessory proteins that enable reconstitution of human α6β4 nAChRs. BARP, an auxiliary subunit of voltage-dependent calcium channels, promoted α6β4 surface expression while IRE1α, an unfolded protein response sensor, enhanced α6β4 receptor assembly. Effects on α6β4 involve BARP's N-terminal region and IRE1α's splicing of XBP1 mRNA. Furthermore, clinical efficacy of nicotinic agents in relieving neuropathic pain best correlated with their activity on α6β4. Finally, BARP-knockout, but not NACHO-knockout mice lacked nicotine-induced antiallodynia, highlighting the functional importance of α6β4 in pain. These results identify roles for IRE1α and BARP in neurotransmitter receptor assembly and unlock drug discovery for the previously elusive α6β4 receptor.
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20
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Hone AJ, Kaas Q, Kearns I, Hararah F, Gajewiak J, Christensen S, Craik DJ, McIntosh JM. Computational and Functional Mapping of Human and Rat α6β4 Nicotinic Acetylcholine Receptors Reveals Species-Specific Ligand-Binding Motifs. J Med Chem 2021; 64:1685-1700. [PMID: 33523678 PMCID: PMC8382285 DOI: 10.1021/acs.jmedchem.0c01973] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Nicotinic acetylcholine receptors (nAChRs) are pharmacological targets for the treatment of neuropathic pain, and the α6β4 subtype has been identified as particularly promising. Rat α6β4 nAChRs are less sensitive to some ligands than the human homologue potentially complicating the use of rodent α6β4 receptors for screening therapeutic compounds. We used molecular dynamics simulations coupled with functional assays to study the interaction between α-conotoxin PeIA and α6β4 nAChRs and to identify key ligand-receptor interactions that contribute to species differences in α-conotoxin potency. Our results show that human and rat α6β4 nAChRs have distinct ligand-binding motifs and show markedly different sensitivities to α-conotoxins. These studies facilitated the creation of PeIA-5667, a peptide that shows 270-fold higher potency for rat α6β4 nAChRs over native PeIA and similar potency for the human homologue. Our results may inform the design of therapeutic ligands that target α6β4 nAChRs for the treatment of neuropathic pain.
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Affiliation(s)
- Arik J Hone
- MIRECC, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah 84148 United States
| | - Quentin Kaas
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072 Australia
| | | | | | | | | | - David J Craik
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072 Australia
| | - J Michael McIntosh
- George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah 84148 United States
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21
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Grant S, Lester HA. Proteins for increased surface expression of the α6β4 nicotinic acetylcholine receptor: nothing but good news? J Clin Invest 2021; 130:5685-5687. [PMID: 33074245 DOI: 10.1172/jci143197] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Useful animal models of disease in neuroscience can make accurate predictions about a therapeutic outcome, a feature known as predictive validity. In this issue of the JCI, Knowland et al. provide an improved model to assess nicotinic acetylcholine receptor (nAChR) ligands for treating chronic pain. The authors identify two proteins, the voltage-dependent calcium channel auxiliary subunit BARP and the unfolded protein response sensor IRE1α, that are required for robust heterologous expression of α6β4, an nAChR subtype in dorsal root ganglia (DRG). This nAChR is a candidate for the analgesic effects of nicotine as well as the frog toxin epibatidine. Now researchers can efficiently screen for α6β4 nAChR-selective agonists using heterologous expression systems. Candidates that emerge will enable researchers to test the predictive validity of mouse models for chronic pain in the nAChR context. If all these steps work, one can envision a class of non-opioid nAChR-targeted analgesics for chronic pain.
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Affiliation(s)
| | - Henry A Lester
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA
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22
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Nicotinic Acetylcholine Receptor Involvement in Inflammatory Bowel Disease and Interactions with Gut Microbiota. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18031189. [PMID: 33572734 PMCID: PMC7908252 DOI: 10.3390/ijerph18031189] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 12/12/2022]
Abstract
The gut-brain axis describes a complex interplay between the central nervous system and organs of the gastrointestinal tract. Sensory neurons of dorsal root and nodose ganglia, neurons of the autonomic nervous system, and immune cells collect and relay information about the status of the gut to the brain. A critical component in this bi-directional communication system is the vagus nerve which is essential for coordinating the immune system’s response to the activities of commensal bacteria in the gut and to pathogenic strains and their toxins. Local control of gut function is provided by networks of neurons in the enteric nervous system also called the ‘gut-brain’. One element common to all of these gut-brain systems is the expression of nicotinic acetylcholine receptors. These ligand-gated ion channels serve myriad roles in the gut-brain axis including mediating fast synaptic transmission between autonomic pre- and postganglionic neurons, modulation of neurotransmitter release from peripheral sensory and enteric neurons, and modulation of cytokine release from immune cells. Here we review the role of nicotinic receptors in the gut-brain axis with a focus on the interplay of these receptors with the gut microbiome and their involvement in dysregulation of gut function and inflammatory bowel diseases.
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23
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The nAChR Chaperone TMEM35a (NACHO) Contributes to the Development of Hyperalgesia in Mice. Neuroscience 2021; 457:74-87. [PMID: 33422618 PMCID: PMC7897319 DOI: 10.1016/j.neuroscience.2020.12.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 12/17/2020] [Accepted: 12/21/2020] [Indexed: 01/21/2023]
Abstract
Pain is a major health problem, affecting over fifty million adults in the US alone, with significant economic cost in medical care and lost productivity. Despite evidence implicating nicotinic acetylcholine receptors (nAChRs) in pathological pain, their specific contribution to pain processing in the spinal cord remains unclear given their presence in both neuronal and non-neuronal cell types. Here we investigated if loss of neuronal-specific TMEM35a (NACHO), a novel chaperone for functional expression of the homomeric α7 and assembly of the heteromeric α3, α4, and α6-containing nAChRs, modulates pain in mice. Mice with tmem35a deletion exhibited thermal hyperalgesia and mechanical allodynia. Intrathecal administration of nicotine and the α7-specific agonist, PHA543613, produced analgesic responses to noxious heat and mechanical stimuli in tmem35a KO mice, respectively, suggesting residual expression of these receptors or off-target effects. Since NACHO is expressed only in neurons, these findings indicate that neuronal α7 nAChR in the spinal cord contributes to heat nociception. To further determine the molecular basis underlying the pain phenotype, we analyzed the spinal cord transcriptome. Compared to WT control, the spinal cord of tmem35a KO mice exhibited 72 differentially-expressed genes (DEGs). These DEGs were mapped onto functional gene networks using the knowledge-based database, Ingenuity Pathway Analysis, and suggests increased neuroinflammation as a potential contributing factor for the hyperalgesia in tmem35a KO mice. Collectively, these findings implicate a heightened inflammatory response in the absence of neuronal NACHO activity. Additional studies are needed to determine the precise mechanism by which NACHO in the spinal cord modulates pain.
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Ho TNT, Abraham N, Lewis RJ. Structure-Function of Neuronal Nicotinic Acetylcholine Receptor Inhibitors Derived From Natural Toxins. Front Neurosci 2020; 14:609005. [PMID: 33324158 PMCID: PMC7723979 DOI: 10.3389/fnins.2020.609005] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 10/30/2020] [Indexed: 12/19/2022] Open
Abstract
Neuronal nicotinic acetylcholine receptors (nAChRs) are prototypical cation-selective, ligand-gated ion channels that mediate fast neurotransmission in the central and peripheral nervous systems. nAChRs are involved in a range of physiological and pathological functions and hence are important therapeutic targets. Their subunit homology and diverse pentameric assembly contribute to their challenging pharmacology and limit their drug development potential. Toxins produced by an extensive range of algae, plants and animals target nAChRs, with many proving pivotal in elucidating receptor pharmacology and biochemistry, as well as providing templates for structure-based drug design. The crystal structures of these toxins with diverse chemical profiles in complex with acetylcholine binding protein (AChBP), a soluble homolog of the extracellular ligand-binding domain of the nAChRs and more recently the extracellular domain of human α9 nAChRs, have been reported. These studies have shed light on the diverse molecular mechanisms of ligand-binding at neuronal nAChR subtypes and uncovered critical insights useful for rational drug design. This review provides a comprehensive overview and perspectives obtained from structure and function studies of diverse plant and animal toxins and their associated inhibitory mechanisms at neuronal nAChRs.
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Affiliation(s)
| | | | - Richard J. Lewis
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
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25
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Chronicling changes in the somatosensory neurons after peripheral nerve injury. Proc Natl Acad Sci U S A 2020; 117:26414-26421. [PMID: 33020310 DOI: 10.1073/pnas.1922618117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Current drug discovery efforts focus on identifying lead compounds acting on a molecular target associated with an established pathological state. Concerted molecular changes that occur in specific cell types during disease progression have generally not been identified. Here, we used constellation pharmacology to investigate rat dorsal root ganglion neurons using two models of peripheral nerve injury: chronic constriction injury (CCI) and spinal nerve ligation (SNL). In these well-established models of neuropathic pain, we show that the onset of chronic pain is accompanied by a dramatic, previously unreported increase in the number of bradykinin-responsive neurons, with larger increases observed after SNL relative to CCI. To define the neurons with altered expression, we charted the temporal course of molecular changes following 1, 3, 6, and 14 d after SNL injury and demonstrated that specific molecular changes have different time courses during the progression to a pain state. In particular, ATP receptors up-regulated on day 1 postinjury, whereas the increase in bradykinin receptors was gradual after day 3 postinjury. We specifically tracked changes in two subsets of neurons: peptidergic and nonpeptidergic nociceptors. Significant increases occurred in ATP responses in nAChR-expressing isolectin B4+ nonpeptidergic neurons 1 d postinjury, whereas peptidergic neurons did not display any significant change. We propose that remodeling of ion channels and receptors occurs in a concerted and cell-specific manner, resulting in the appearance of bradykinin-responsive neuronal subclasses that are relevant to chronic pain.
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Toma W, Ulker E, Alqasem M, AlSharari SD, McIntosh JM, Damaj MI. Behavioral and Molecular Basis of Cholinergic Modulation of Pain: Focus on Nicotinic Acetylcholine Receptors. Curr Top Behav Neurosci 2020; 45:153-166. [PMID: 32468494 DOI: 10.1007/7854_2020_135] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) have emerged as a novel therapeutic strategy for pain and inflammatory disorders. In particular, α4β2∗, α7, and α9α10 nAChR subtypes have been investigated as potential targets to treat pain. The nAChRs are distributed on the pain transmission pathways, including central and peripheral nervous systems and immune cells as well. Several agonists for α4β2∗ nAChR subtypes have been investigated in multiple animal pain models with promising results. However, studies in human indicated a narrow therapeutic window for α4β2∗ agonists. Furthermore, animal studies suggest that using agonists for α7 nAChR subtype and antagonists for α9α10 nAChR subtypes are potential novel therapies for chronic pain management, including inflammatory and neuropathic pain. More recently, alternative nAChRs ligands such as positive allosteric modulators and silent agonists have shown potential to develop into new treatments for chronic pain.
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Affiliation(s)
- Wisam Toma
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Esad Ulker
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Mashael Alqasem
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Shakir D AlSharari
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - J Michael McIntosh
- Departments of Psychiatry and Biology, University of Utah, Salt Lake City, UT, USA
| | - M Imad Damaj
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA.
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Hoofwijk DMN, Reij RRI, Rutten BPF, Kenis G, Theunissen M, Joosten EA, Buhre WF, den Hoogen NJ. Genetic polymorphisms and prediction of chronic post-surgical pain after hysterectomy-a subgroup analysis of a multicenter cohort study. Acta Anaesthesiol Scand 2019; 63:1063-1073. [PMID: 31206175 DOI: 10.1111/aas.13413] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 03/26/2019] [Accepted: 05/08/2019] [Indexed: 12/29/2022]
Abstract
BACKGROUND Chronic post-surgical pain (CPSP) is a serious problem. Clinical and psychological variables have not been able to explain all observed variance in prevalence and severity of CPSP. The first objective is to determine the association between genetic polymorphisms and the prevalence of CPSP after hysterectomy. The second objective is to analyze if the implementation of genetic polymorphisms into a previously performed clinical and psychological predictor analysis on the development of CPSP after hysterectomy will improve its discriminatory power. METHODS A prospective multicenter cohort study was performed in patients undergoing hysterectomy for benign indication. Clinical and psychological variables were collected by questionnaires in the week before surgery, post-operatively up to day 4, 3 and 12 months after hysterectomy. Blood was collected and 16 polymorphisms previously suggested to be correlated to CPSP (COMT, GCH1, KCNS1, CACNG2, and OPRM1) were genotyped. Logistic regression analyses were performed. RESULTS Three hundred and forty-five patients were available for the genetic analyses. The prevalence of CPSP 3 months post-operatively was 10.5% and after 12 months 7.9%. The polymorphism rs4818 within the COMT gene was associated with the prevalence of CPSP after 3 months. No polymorphisms were associated with CPSP after 12 months. The addition of rs4818 to the prediction model did not change its discriminatory power significantly. CONCLUSION The rs4818 polymorphism within the COMT gene was associated with the prevalence of CPSP 3 months after hysterectomy, but the implementation of rs4818 into the prediction model did not significantly improve the chance of identifying hysterectomy patients at risk for CPSP.
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Affiliation(s)
- Daisy M. N. Hoofwijk
- Department of Anesthesiology and Pain Medicine Maastricht University Medical Center+ Maastricht The Netherlands
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences Maastricht University Medical Center+ Maastricht The Netherlands
| | - Roel R. I. Reij
- Department of Anesthesiology and Pain Medicine Maastricht University Medical Center+ Maastricht The Netherlands
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences Maastricht University Medical Center+ Maastricht The Netherlands
| | - Bart P. F. Rutten
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences Maastricht University Medical Center+ Maastricht The Netherlands
- Faculty of Health, Medicine and Life Sciences, Department of Psychiatry and Neuropsychology Maastricht University Medical Center+ Maastricht The Netherlands
| | - Gunter Kenis
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences Maastricht University Medical Center+ Maastricht The Netherlands
- Faculty of Health, Medicine and Life Sciences, Department of Psychiatry and Neuropsychology Maastricht University Medical Center+ Maastricht The Netherlands
| | - Maurice Theunissen
- Department of Anesthesiology and Pain Medicine Maastricht University Medical Center+ Maastricht The Netherlands
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences Maastricht University Medical Center+ Maastricht The Netherlands
| | - Elbert A. Joosten
- Department of Anesthesiology and Pain Medicine Maastricht University Medical Center+ Maastricht The Netherlands
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences Maastricht University Medical Center+ Maastricht The Netherlands
| | - Wolfgang F. Buhre
- Department of Anesthesiology and Pain Medicine Maastricht University Medical Center+ Maastricht The Netherlands
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences Maastricht University Medical Center+ Maastricht The Netherlands
| | - Nynke J. den Hoogen
- Department of Anesthesiology and Pain Medicine Maastricht University Medical Center+ Maastricht The Netherlands
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences Maastricht University Medical Center+ Maastricht The Netherlands
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van Hout M, Valdes A, Christensen SB, Tran PT, Watkins M, Gajewiak J, Jensen AA, Olivera BM, McIntosh JM. α-Conotoxin VnIB from Conus ventricosus is a potent and selective antagonist of α6β4* nicotinic acetylcholine receptors. Neuropharmacology 2019; 157:107691. [PMID: 31255696 DOI: 10.1016/j.neuropharm.2019.107691] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 06/05/2019] [Accepted: 06/26/2019] [Indexed: 01/20/2023]
Abstract
α6-containing (α6*) nicotinic acetylcholine receptors (nAChRs) are expressed throughout the periphery and the central nervous system and constitute putative therapeutic targets in pain, addiction and movement disorders. The α6β2* nAChRs are relatively well studied, in part due to the availability of target specific α-conotoxins (α-Ctxs). In contrast, all native α-Ctxs identified that potently block α6β4 nAChRs exhibit higher potencies for the closely related α6β2β3 and/or α3β4 subtypes. In this study, we have identified a novel peptide from Conus ventricosus with pronounced selectivity for the α6β4 nAChR. The peptide-encoding gene was cloned from genomic DNA and the predicted mature peptide, α-Ctx VnIB, was synthesized. The functional properties of VnIB were characterized at rat and human nAChRs expressed in Xenopus oocytes by two-electrode voltage clamp electrophysiology. VnIB potently inhibited ACh-evoked currents at rα6β4 and rα6/α3β4 nAChRs, displayed ∼20-fold and ∼250-fold lower potencies at rα3β4 and rα6/α3β2β3 receptors, respectively, and exhibited negligible effects at eight other nAChR subtypes. Interestingly, even higher degrees of selectivity were observed for hα6/α3β4 over hα6/α3β2β3 and hα3β4 receptors. Finally, VnIB displayed fast binding kinetics at rα6/α3β4 (on-rate t½ = 0.87 min-1, off-rate t½ = 2.7 min-1). The overall preference of VnIB for β4* over β2* nAChRs is similar to the selectivity profiles of other 4/6 α-Ctxs. However, in contrast to previously identified native α-Ctxs targeting α6* nAChRs, VnIB displays pronounced selectivity for α6β4 nAChRs over both α3β4 and α6β2β3 receptors. VnIB thus represents a novel molecular probe for elucidating the physiological role and therapeutic properties of α6β4* nAChRs.
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Affiliation(s)
- Marloes van Hout
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Amanda Valdes
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
| | - Sean B Christensen
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA.
| | - Phuong T Tran
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
| | - Maren Watkins
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA; Department of Pathology, University of Utah, Salt Lake City, UT, 84112, USA.
| | - Joanna Gajewiak
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA.
| | - Anders A Jensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | | | - J Michael McIntosh
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA; Department of Psychiatry, University of Utah, Salt Lake City, UT, 84108, USA; George E. Wahlen Veterans Affair Medical Center, Salt Lake City, UT, 84148, USA.
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Chidambaran V, Gang Y, Pilipenko V, Ashton M, Ding L. Systematic Review and Meta-Analysis of Genetic Risk of Developing Chronic Postsurgical Pain. THE JOURNAL OF PAIN 2019; 21:2-24. [PMID: 31129315 DOI: 10.1016/j.jpain.2019.05.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 04/06/2019] [Accepted: 05/20/2019] [Indexed: 02/08/2023]
Abstract
Chronic postsurgical pain (CPSP) is a significant detriment to postsurgical recovery and a risk factor for prolonged opioid use. Emerging evidence suggests the estimated heritability for chronic pain is 45% and that genetic factors partially explain individual susceptibility to CPSP. The aim of this study was to systematically review, assess quality, and summarize the studies in humans that have investigated genetic factors associated with CPSP. We also conducted a meta-analysis to derive a single effect size for evaluable genetic associations with CPSP. Our comprehensive literature search included review of 21 full-text articles evaluating variants of 69 genes for association with CPSP. We found significant gene variant associations reported for variants/haplotypes of 26 genes involved in neurotransmission, pain signaling, immune responses and neuroactive ligand-receptor interaction, with CPSP. Six variants of 5 genes (COMT: rs4680 and rs6269, OPRM1: rs1799971, GCH1: rs3783641, KCNS1: rs734784 and TNFA: rs1800629), were evaluated by more than one study and were included in the meta-analysis. At rs734784 (A>G) of KCNS1, presence of G allele marginally increased risk of CPSP (Additive genetic model; Odds ratio: 1.511; 95% CI 1-2.284; P value: .050), while the other variants did not withstand meta-analyses criteria. Our findings demonstrate the role of genetic factors with different functions in CPSP, and also emphasize that single genetic factors have small effect sizes in explaining complex conditions like CPSP. Heterogeneity in surgical cohorts, population structure, and outcome definitions, as well as small number of available studies evaluating same variants, limit the meta-analysis. There is a need for large-scale, homogenous, replication studies to validate candidate genes, and understand the underlying biological networks underpinning CPSP. PERSPECTIVE: Our systematic review comprehensively describes 21 studies evaluating genetic association with CPSP, and limitations thereof. A meta-analysis of 6 variants (5 genes) found marginally increased risk for CPSP associated with rs734784 A>G of the potassium voltage-gated channel gene (KCNS1). Understanding genetic predisposition for CPSP will enable prediction and personalized management.
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Affiliation(s)
- Vidya Chidambaran
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio.
| | - Yang Gang
- Division of Biostatistics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Mathematical Sciences, University of Cincinnati, Cincinnati, Ohio
| | - Valentina Pilipenko
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Maria Ashton
- Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Lili Ding
- Division of Biostatistics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
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Machoy-Mokrzyńska A, Starzyńska-Sadura Z, Dziedziejko V, Safranow K, Kurzawski M, Leźnicka K, Sulżyc-Bielicka V, Jurewicz A, Bohatyrewicz A, Białecka M. Association of COMT gene variability with pain intensity in patients after total hip replacement. Scandinavian Journal of Clinical and Laboratory Investigation 2019; 79:202-207. [PMID: 30822160 DOI: 10.1080/00365513.2019.1576920] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Pain is one of the most interdisciplinary clinical symptoms of a disease. The aim of the study was to evaluate the association of COMT gene polymorphism with pain perception in patients after total hip replacement (THR). The study included 195 patients qualified for surgical treatment (THR) due to osteoarthritis. Patients previously undergoing hip replacement subsequently underwent multimodal pain management therapy, in accordance with the recommendations for treating postoperative pain. The intensity of pain was measured three times at pre-defined time intervals: 1.5, 6 and 12 months after hip replacement, using the visual analogue scale. Single nucleotide polymorphism (SNP) in the COMT gene rs4680: A>G (Val158Met), rs6269: A>G (promoter region), rs4633: C>T (His62His) and rs4818: C>G (Leu136Leu) was genotyped. COMT SNP frequency distribution was analysed. For rs6269 and rs4818, the minor allele was the G allele (38.7 and 38.5%, respectively). It was also observed that rs4633 (T) allele frequency (50%) equalled that of the rs4680 (A) allele (50%). We assessed COMT haplotype frequency in the patients studied. The most frequent haplotype was haplotype M (ATCA) (50%), the rarest haplotype was haplotype R (ATGG), with a frequency of 0.3%. The most frequent diplotype was H/M, which was found in 37.95% of the patients. The frequency of other diplotypes was: M/M-24.10%, H/H-15.90% and L/M-13.33%. The study showed a significant association of rs4818 G allele and equivalent COMT H haplotype with lower sensitivity to pain after hip replacement.
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Affiliation(s)
- Anna Machoy-Mokrzyńska
- a Department of Experimental and Clinical Pharmacology , Pomeranian Medical University , Szczecin , Poland
| | - Zuzanna Starzyńska-Sadura
- a Department of Experimental and Clinical Pharmacology , Pomeranian Medical University , Szczecin , Poland
| | - Violetta Dziedziejko
- b Department of Biochemistry and Medical Chemistry , Pomeranian Medical University , Szczecin , Poland
| | - Krzysztof Safranow
- b Department of Biochemistry and Medical Chemistry , Pomeranian Medical University , Szczecin , Poland
| | - Mateusz Kurzawski
- a Department of Experimental and Clinical Pharmacology , Pomeranian Medical University , Szczecin , Poland
| | - Katarzyna Leźnicka
- c Faculty of Physical Education , Gdansk University of Physical Education and Sport , Gdańsk , Poland
| | | | - Alina Jurewicz
- e Department of Orthopaedics Traumatology and Orthopaedic Oncology , Pomeranian Medical University , Szczecin , Poland
| | - Andrzej Bohatyrewicz
- e Department of Orthopaedics Traumatology and Orthopaedic Oncology , Pomeranian Medical University , Szczecin , Poland
| | - Monika Białecka
- f Department of Pharmacokinetics and Therapeutic Drug Monitoring , Pomeranian Medical University , Szczecin , Poland
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31
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Smith SB, Parisien M, Bair E, Belfer I, Chabot-Doré AJ, Gris P, Khoury S, Tansley S, Torosyan Y, Zaykin DV, Bernhardt O, de Oliveira Serrano P, Gracely RH, Jain D, Järvelin MR, Kaste LM, Kerr KF, Kocher T, Lähdesmäki R, Laniado N, Laurie CC, Laurie CA, Männikkö M, Meloto CB, Nackley AG, Nelson SC, Pesonen P, Ribeiro-Dasilva MC, Rizzatti-Barbosa CM, Sanders AE, Schwahn C, Sipilä K, Sofer T, Teumer A, Mogil JS, Fillingim RB, Greenspan JD, Ohrbach R, Slade GD, Maixner W, Diatchenko L. Genome-wide association reveals contribution of MRAS to painful temporomandibular disorder in males. Pain 2019; 160:579-591. [PMID: 30431558 PMCID: PMC6377338 DOI: 10.1097/j.pain.0000000000001438] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 10/25/2018] [Indexed: 02/06/2023]
Abstract
Painful temporomandibular disorders (TMDs) are the leading cause of chronic orofacial pain, but its underlying molecular mechanisms remain obscure. Although many environmental factors have been associated with higher risk of developing painful TMD, family and twin studies support a heritable genetic component as well. We performed a genome-wide association study assuming an additive genetic model of TMD in a discovery cohort of 999 cases and 2031 TMD-free controls from the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) study. Using logistic models adjusted for sex, age, enrollment site, and race, we identified 3 distinct loci that were significant in combined or sex-segregated analyses. A single-nucleotide polymorphism on chromosome 3 (rs13078961) was significantly associated with TMD in males only (odds ratio = 2.9, 95% confidence interval: 2.02-4.27, P = 2.2 × 10). This association was nominally replicated in a meta-analysis of 7 independent orofacial pain cohorts including 160,194 participants (odds ratio = 1.16, 95% confidence interval: 1.0-1.35, P = 2.3 × 10). Functional analysis in human dorsal root ganglia and blood indicated this variant is an expression quantitative trait locus, with the minor allele associated with decreased expression of the nearby muscle RAS oncogene homolog (MRAS) gene (beta = -0.51, P = 2.43 × 10). Male mice, but not female mice, with a null mutation of Mras displayed persistent mechanical allodynia in a model of inflammatory pain. Genetic and behavioral evidence support a novel mechanism by which genetically determined MRAS expression moderates the resiliency to chronic pain. This effect is male-specific and may contribute to the lower rates of painful TMD in men.
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Affiliation(s)
- Shad B. Smith
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University, Durham, NC, United States
| | - Marc Parisien
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Eric Bair
- Center for Pain Research and Innovation, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Inna Belfer
- National Center for Complementary and Integrative Health, National Institutes of Health, Bethesda, MD, United States
| | | | - Pavel Gris
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Samar Khoury
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Shannon Tansley
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
- Department of Psychology, McGill University, Montreal, QC, Canada
| | - Yelizaveta Torosyan
- Division of Epidemiology, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD, United States
| | - Dmitri V. Zaykin
- Biostatistics & Computational Biology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States
| | - Olaf Bernhardt
- Department of Restorative Dentistry, Periodontology, Endodontology, Preventive Dentistry and Pediatric Dentistry, University Medicine Greifswald, Greifswald, Germany
| | - Priscila de Oliveira Serrano
- Department of Prosthesis and Periodontology, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil
| | - Richard H. Gracely
- Center for Pain Research and Innovation, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Deepti Jain
- Department of Biostatistics, University of Washington, Seattle, WA, United States
| | - Marjo-Riitta Järvelin
- Department of Epidemiology and Biostatistics, Medical Research Council-Public Health England Centre for Environment and Health, School of Public Health, Imperial College London, London, United Kingdom
- Center for Life Course Health Research, Faculty of Medicine, University of Oulu, Oulu, Finland
- Biocenter Oulu, University of Oulu, and Unit of Primary Care, Oulu University Hospital, Oulu, Finland
- Department of Life Sciences, College of Health and Life Sciences, Brunel University London, United Kingdom
| | - Linda M. Kaste
- Department of Pediatric Dentistry, College of Dentistry, University of Illinois at Chicago, Chicago, IL, United States
| | - Kathleen F. Kerr
- Department of Biostatistics, University of Washington, Seattle, WA, United States
| | - Thomas Kocher
- Department of Restorative Dentistry, Periodontology, Endodontology, Preventive Dentistry and Pediatric Dentistry, University Medicine Greifswald, Greifswald, Germany
| | - Raija Lähdesmäki
- Research Unit of Oral Health Sciences, Faculty of Medicine, University of Oulu, Oulu, Finland
- Medical Research Center Oulu, Oulu University Hospital, Oulu, Finland
| | - Nadia Laniado
- Department of Dentistry, Jacobi Medical Center/Albert Einstein College of Medicine, Bronx, NY, United States
| | - Cathy C. Laurie
- Department of Biostatistics, University of Washington, Seattle, WA, United States
| | - Cecelia A. Laurie
- Department of Biostatistics, University of Washington, Seattle, WA, United States
| | - Minna Männikkö
- Center for Life Course Health Research, Faculty of Medicine, University of Oulu, Oulu, Finland
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Carolina B. Meloto
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Andrea G. Nackley
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University, Durham, NC, United States
| | - Sarah C. Nelson
- Department of Biostatistics, University of Washington, Seattle, WA, United States
| | - Paula Pesonen
- Northern Finland Birth Cohorts, Faculty of Medicine, University of Oulu, Finland
| | - Margarete C. Ribeiro-Dasilva
- Division of Prosthodontics, Restorative Dental Science Department, College of Dentistry, University of Florida, Gainesville, FL, United States
| | - Celia M. Rizzatti-Barbosa
- Department of Prosthesis and Periodontology, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil
| | - Anne E. Sanders
- Center for Pain Research and Innovation, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Dental Ecology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Christian Schwahn
- Department of Prosthetic Dentistry, Gerodontology and Biomaterials, University Medicine Greifswald, Greifswald, Germany
| | - Kirsi Sipilä
- Research Unit of Oral Health Sciences, Faculty of Medicine, University of Oulu, Oulu, Finland
- Medical Research Center Oulu, Oulu University Hospital, Oulu, Finland
- Institute of Dentistry, University of Eastern Finland, Kuopio, Finland
- Oral and Maxillofacial Department, Kuopio University Hospital, Kuopio, Finland
| | - Tamar Sofer
- Department of Medicine, Harvard Medical School, Boston, MA, United States
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, United States
| | - Alexander Teumer
- Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany
| | - Jeffrey S. Mogil
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
- Department of Psychology, McGill University, Montreal, QC, Canada
| | - Roger B. Fillingim
- Department of Community Dentistry and Behavioral Science, University of Florida, Gainesville, FL, United States
| | - Joel D. Greenspan
- Department of Neural and Pain Sciences, Brotman Facial Pain Clinic, University of Maryland, School of Dentistry, Baltimore, MD, United States
| | - Richard Ohrbach
- Department of Oral Diagnostic Services, University at Buffalo, Buffalo, NY, United States
| | - Gary D. Slade
- Center for Pain Research and Innovation, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Dental Ecology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - William Maixner
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University, Durham, NC, United States
| | - Luda Diatchenko
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
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Ray P, Torck A, Quigley L, Wangzhou A, Neiman M, Rao C, Lam T, Kim JY, Kim TH, Zhang MQ, Dussor G, Price TJ. Comparative transcriptome profiling of the human and mouse dorsal root ganglia: an RNA-seq-based resource for pain and sensory neuroscience research. Pain 2019; 159:1325-1345. [PMID: 29561359 DOI: 10.1097/j.pain.0000000000001217] [Citation(s) in RCA: 224] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Molecular neurobiological insight into human nervous tissues is needed to generate next-generation therapeutics for neurological disorders such as chronic pain. We obtained human dorsal root ganglia (hDRG) samples from organ donors and performed RNA-sequencing (RNA-seq) to study the hDRG transcriptional landscape, systematically comparing it with publicly available data from a variety of human and orthologous mouse tissues, including mouse DRG (mDRG). We characterized the hDRG transcriptional profile in terms of tissue-restricted gene coexpression patterns and putative transcriptional regulators, and formulated an information-theoretic framework to quantify DRG enrichment. Relevant gene families and pathways were also analyzed, including transcription factors, G-protein-coupled receptors, and ion channels. Our analyses reveal an hDRG-enriched protein-coding gene set (∼140), some of which have not been described in the context of DRG or pain signaling. Most of these show conserved enrichment in mDRG and were mined for known drug-gene product interactions. Conserved enrichment of the vast majority of transcription factors suggests that the mDRG is a faithful model system for studying hDRG, because of evolutionarily conserved regulatory programs. Comparison of hDRG and tibial nerve transcriptomes suggests trafficking of neuronal mRNA to axons in adult hDRG, and are consistent with studies of axonal transport in rodent sensory neurons. We present our work as an online, searchable repository (https://www.utdallas.edu/bbs/painneurosciencelab/sensoryomics/drgtxome), creating a valuable resource for the community. Our analyses provide insight into DRG biology for guiding development of novel therapeutics and a blueprint for cross-species transcriptomic analyses.
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Affiliation(s)
- Pradipta Ray
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA.,Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Andrew Torck
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Lilyana Quigley
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Andi Wangzhou
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Matthew Neiman
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Chandranshu Rao
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Tiffany Lam
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Ji-Young Kim
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Tae Hoon Kim
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Michael Q Zhang
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Gregory Dussor
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Theodore J Price
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA
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Influence of neuropathic pain on nicotinic acetylcholine receptor plasticity and behavioral responses to nicotine in rats. Pain 2019; 159:2179-2191. [PMID: 29939964 DOI: 10.1097/j.pain.0000000000001318] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Tobacco smoking is particularly evident in individuals experiencing chronic pain. This complex relationship is poorly understood at both molecular and behavioral levels. Here, we describe experiments aimed at understanding whether a chronic pain state induces neuroadaptations into the brain or peripheral nerves that involve nicotinic acetylcholine receptors (nAChRs) and whether these neuroadaptations directly lead to increased vulnerability to nicotine addiction or to the development of coping strategies to relieve pain symptoms. We found that ligation of the rat L5 spinal nerve led to a dramatic downregulation in the mRNA expression levels of all nAChR subunits examined in dorsal root ganglia and a time-dependent downregulation of discrete subunits, particularly in the cingulate cortex and the amygdala. Spinal nerve ligation and sham-operated rats showed minor or no changes in patterns of acquisition and motivation for nicotine taking. Spinal nerve ligation rats also showed similar vulnerability to nicotine seeking as sham animals when reinstatement was induced by nicotine-associated cues, but failed to reinstate lever pressing when relapse was induced by nicotine priming. Spinal nerve ligation and sham rats were equally sensitive to nicotine-induced anxiety-like behavior and antinociception; however, nicotine produced a potent and long-lasting antiallodynic effect in spinal nerve ligation rats. These results demonstrate that chronic pain leads to plasticity of nAChRs that do not directly facilitate nicotine addictive behaviors. Instead, nicotine potently decreases allodynia, an effect that could lead to increased nicotine consumption in chronic pain subjects.
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Dodick DW, Reed ML, Fanning KM, Munjal S, Alam A, Buse DC, Schwedt TJ, Lipton RB. Predictors of allodynia in persons with migraine: Results from the Migraine in America Symptoms and Treatment (MAST) study. Cephalalgia 2019; 39:873-882. [DOI: 10.1177/0333102418825346] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Background Cutaneous allodynia is a common clinical feature of migraine that has been associated with reduced efficacy of acute migraine treatments and an increased risk of disease progression. Objective Identify factors associated with allodynia in a sample of adults with migraine. Methods An online survey panel was used to identify adults with migraine who averaged at least 1 monthly headache day over the previous 3 months. Data on sociodemographics, headache frequency, headache pain intensity, migraine symptom severity, medication use, depression and anxiety, and cutaneous allodynia (via the Allodynia Symptom Checklist) were obtained. Binary logistic modeling predicted the presence of allodynia. Odds ratios and 95% confidence intervals (CI) were calculated. Results In total, 15,133 individuals with migraine met the eligibility criteria. Mean age was 43.1 years, 73.0% were female, and 81.0% were Caucasian. Allodynia was present in 39.9%. The fully adjusted model, controlling for sociodemographics and headache features, demonstrated that allodynia was significantly associated with a higher migraine symptom severity score (odds ratio 1.17, confidence interval 1.15, 1.19) and more severe pain intensity (odds ratio 1.11, confidence interval 1.08, 1.14); probable depression and/or anxiety (odds ratio 1.83, confidence interval 1.67, 2.00); and overuse of acute medication (odds ratio 1.23, confidence interval 1.09, 1.38). A higher number of monthly headache days increased the likelihood of allodynia, but the effect was attenuated in the fully adjusted model. Conclusion In a representative sample of US adults with migraine, there were significant associations between allodynia and headache frequency and intensity, anxiety and/or depression, symptom severity, and acute medication overuse.
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Affiliation(s)
| | | | | | - Sagar Munjal
- Promius Pharma, a subsidiary of Dr. Reddy’s Laboratories, Princeton, NJ, USA
| | - Aftab Alam
- Promius Pharma, a subsidiary of Dr. Reddy’s Laboratories, Princeton, NJ, USA
| | - Dawn C Buse
- Department of Neurology, Albert Einstein College of Medicine, New York, NY, USA
| | | | - Richard B Lipton
- Department of Neurology, Albert Einstein College of Medicine, New York, NY, USA
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35
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Megat S, Ray PR, Moy JK, Lou TF, Barragán-Iglesias P, Li Y, Pradhan G, Wanghzou A, Ahmad A, Burton MD, North RY, Dougherty PM, Khoutorsky A, Sonenberg N, Webster KR, Dussor G, Campbell ZT, Price TJ. Nociceptor Translational Profiling Reveals the Ragulator-Rag GTPase Complex as a Critical Generator of Neuropathic Pain. J Neurosci 2019; 39:393-411. [PMID: 30459229 PMCID: PMC6335757 DOI: 10.1523/jneurosci.2661-18.2018] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 11/05/2018] [Accepted: 11/14/2018] [Indexed: 12/11/2022] Open
Abstract
Nociceptors, sensory neurons in the DRG that detect damaging or potentially damaging stimuli, are key drivers of neuropathic pain. Injury to these neurons causes activation of translation regulation signaling, including the mechanistic target of rapamycin complex 1 (mTORC1) and mitogen-activated protein kinase interacting kinase (MNK) eukaryotic initiation factor (eIF) 4E pathways. This is a mechanism driving changes in excitability of nociceptors that is critical for the generation of chronic pain states; however, the mRNAs that are translated to lead to this plasticity have not been elucidated. To address this gap in knowledge, we used translating ribosome affinity purification in male and female mice to comprehensively characterize mRNA translation in Scn10a-positive nociceptors in chemotherapy-induced neuropathic pain (CIPN) caused by paclitaxel treatment. This unbiased method creates a new resource for the field, confirms many findings in the CIPN literature and also find extensive evidence for new target mechanisms that may cause CIPN. We provide evidence that an underlying mechanism of CIPN is sustained mTORC1 activation driven by MNK1-eIF4E signaling. RagA, a GTPase controlling mTORC1 activity, is identified as a novel target of MNK1-eIF4E signaling. This demonstrates a novel translation regulation signaling circuit wherein MNK1-eIF4E activity drives mTORC1 via control of RagA translation. CIPN and RagA translation are strongly attenuated by genetic ablation of eIF4E phosphorylation, MNK1 elimination or treatment with the MNK inhibitor eFT508. We identify a novel translational circuit for the genesis of neuropathic pain caused by chemotherapy with important implications for therapeutics.SIGNIFICANCE STATEMENT Neuropathic pain affects up to 10% of the population, but its underlying mechanisms are incompletely understood, leading to poor treatment outcomes. We used translating ribosome affinity purification technology to create a comprehensive translational profile of DRG nociceptors in naive mice and at the peak of neuropathic pain induced by paclitaxel treatment. We reveal new insight into how mechanistic target of rapamycin complex 1 is activated in neuropathic pain pointing to a key role of MNK1-eIF4E-mediated translation of a complex of mRNAs that control mechanistic target of rapamycin complex 1 signaling at the surface of the lysosome. We validate this finding using genetic and pharmacological techniques. Our work strongly suggests that MNK1-eIF4E signaling drives CIPN and that a drug in human clinical trials, eFT508, may be a new therapeutic for neuropathic pain.
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Affiliation(s)
- Salim Megat
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Pradipta R Ray
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Jamie K Moy
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
| | - Tzu-Fang Lou
- University of Texas at Dallas, Department of Biological Sciences, 800 Campbell Rd, Richardson, Texas, 75080
| | - Paulino Barragán-Iglesias
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Yan Li
- University of Texas M.D. Anderson Cancer Center, Department of Anesthesia and Pain Medicine, 1400 Holcombe Boulevard, Houston, TX 77030
| | - Grishma Pradhan
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Andi Wanghzou
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Ayesha Ahmad
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Michael D Burton
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Robert Y North
- University of Texas M.D. Anderson Cancer Center, Department of Anesthesia and Pain Medicine, 1400 Holcombe Boulevard, Houston, TX 77030
| | - Patrick M Dougherty
- University of Texas M.D. Anderson Cancer Center, Department of Anesthesia and Pain Medicine, 1400 Holcombe Boulevard, Houston, TX 77030
| | - Arkady Khoutorsky
- McGill University, Department of Anesthesia, 001 Boulevard Décarie C05.2000, Montréal, QC H4A 3J1, Canada
| | - Nahum Sonenberg
- McGill University, Goodman Cancer Research Center, Department of Biochemistry, 1160 Pine Ave W, Montreal, QC H3A 1A3, Canada, and
| | - Kevin R Webster
- eFFECTOR Therapeutics, 11180 Roselle St, San Diego, CA 92121
| | - Gregory Dussor
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
| | - Zachary T Campbell
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080,
- University of Texas at Dallas, Department of Biological Sciences, 800 Campbell Rd, Richardson, Texas, 75080
| | - Theodore J Price
- University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 Campbell Rd, Richardson, Texas, 75080,
- University of Texas at Dallas, Center for Advanced Pain Studies, 800 Campbell Rd, Richardson, Texas, 75080
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Schmid R, Evans RJ. ATP-Gated P2X Receptor Channels: Molecular Insights into Functional Roles. Annu Rev Physiol 2018; 81:43-62. [PMID: 30354932 DOI: 10.1146/annurev-physiol-020518-114259] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In the nervous system, ATP is co-stored in vesicles with classical transmitters and released in a regulated manner. ATP from the intracellular compartment can also exit the cell through hemichannels and following shear stress or membrane damage. In the past 30 years, the action of ATP as an extracellular transmitter at cell-surface receptors has evolved from somewhat of a novelty that was treated with skepticism to purinergic transmission being accepted as having widespread important functional roles mediated by ATP-gated ionotropic P2X receptors (P2XRs). This review focuses on work published in the last five years and provides an overview of ( a) structural studies, ( b) the molecular basis of channel properties and regulation of P2XRs, and ( c) the physiological and pathophysiological roles of ATP acting at defined P2XR subtypes.
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Affiliation(s)
- Ralf Schmid
- Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, United Kingdom; .,Leicester Institute of Structural and Chemical Biology, University of Leicester, Leicester LE1 7RH, United Kingdom
| | - Richard J Evans
- Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, United Kingdom;
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Hone AJ, Talley TT, Bobango J, Huidobro Melo C, Hararah F, Gajewiak J, Christensen S, Harvey PJ, Craik DJ, McIntosh JM. Molecular determinants of α-conotoxin potency for inhibition of human and rat α6β4 nicotinic acetylcholine receptors. J Biol Chem 2018; 293:17838-17852. [PMID: 30249616 DOI: 10.1074/jbc.ra118.005649] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 09/20/2018] [Indexed: 12/15/2022] Open
Abstract
Nicotinic acetylcholine receptors (nAChRs) containing α6 and β4 subunits are expressed by dorsal root ganglion neurons and have been implicated in neuropathic pain. Rodent models are often used to evaluate the efficacy of analgesic compounds, but species differences may affect the activity of some nAChR ligands. A previous candidate α-conotoxin-based therapeutic yielded promising results in rodent models, but failed in human clinical trials, emphasizing the importance of understanding species differences in ligand activity. Here, we show that human and rat α6/α3β4 nAChRs expressed in Xenopus laevis oocytes exhibit differential sensitivity to α-conotoxins. Sequence homology comparisons of human and rat α6β4 nAChR subunits indicated that α6 residues forming the ligand-binding pocket are highly conserved between the two species, but several residues of β4 differed, including a Leu-Gln difference at position 119. X-ray crystallography of α-conotoxin PeIA complexed with the Aplysia californica acetylcholine-binding protein (AChBP) revealed that binding of PeIA orients Pro13 in close proximity to residue 119 of the AChBP complementary subunit. Site-directed mutagenesis studies revealed that Leu119 of human β4 contributes to higher sensitivity of human α6/α3β4 nAChRs to α-conotoxins, and structure-activity studies indicated that PeIA Pro13 is critical for high potency. Human and rat α6/α3β4 nAChRs displayed differential sensitivities to perturbations of the interaction between PeIA Pro13 and residue 119 of the β4 subunit. These results highlight the potential significance of species differences in α6β4 nAChR pharmacology that should be taken into consideration when evaluating the activity of candidate human therapeutics in rodent models.
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Affiliation(s)
| | | | - Janet Bobango
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, Montana 59812
| | | | | | | | | | - Peta J Harvey
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia
| | - David J Craik
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia
| | - J Michael McIntosh
- From the Departments of Biology; Psychiatry, University of Utah, Salt Lake City, Utah 84112; George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah 84148.
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Hoofwijk DMN, van Reij RRI, Rutten BP, Kenis G, Buhre WF, Joosten EA. Genetic polymorphisms and their association with the prevalence and severity of chronic postsurgical pain: a systematic review. Br J Anaesth 2018; 117:708-719. [PMID: 27956669 DOI: 10.1093/bja/aew378] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Although several patient characteristic, clinical, and psychological risk factors for chronic postsurgical pain (CPSP) have been identified, genetic variants including single nucleotide polymorphisms have also become of interest as potential risk factors for the development of CPSP. The aim of this review is to summarize the current evidence on genetic polymorphisms associated with the prevalence and severity of CPSP in adult patients. METHODS A systematic review of the literature was performed, and additional literature was obtained by reference tracking. The primary outcome was CPSP, defined as pain at least 2 months after the surgery. Studies performed exclusively in animals were excluded. RESULTS Out of the 1001 identified studies, 14 studies were selected for inclusion. These studies described 5269 participants in 17 cohorts. A meta-analysis was not possible because of heterogeneity of data and data analysis. Associations with the prevalence or severity of CPSP were reported for genetic variants in the COMT gene, OPRM1, potassium channel genes, GCH1, CACNG, CHRNA6, P2X7R, cytokine-associated genes, human leucocyte antigens, DRD2, and ATXN1 CONCLUSIONS: Research on the topic of genetic variants associated with CPSP is still in its initial phase. Hypothesis-free, genome-wide association studies on large cohorts are needed in this field. In addition, future studies may also integrate genetic risk factors and patient characteristic, clinical, and psychological predictors for CPSP.
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Affiliation(s)
- D M N Hoofwijk
- Department of Anesthesiology and Pain Medicine, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - R R I van Reij
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - B P Rutten
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - G Kenis
- School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - W F Buhre
- Department of Anesthesiology and Pain Medicine, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - E A Joosten
- Department of Anesthesiology and Pain Medicine, Maastricht University Medical Center+, Maastricht, The Netherlands.,School for Mental Health and Neuroscience (MHeNs), Faculty of Health, Medicine and Life Sciences, Maastricht University Medical Centre, Maastricht, The Netherlands
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Nissen NI, Anderson KR, Wang H, Lee HS, Garrison C, Eichelberger SA, Ackerman K, Im W, Miwa JM. Augmenting the antinociceptive effects of nicotinic acetylcholine receptor activity through lynx1 modulation. PLoS One 2018; 13:e0199643. [PMID: 29969495 PMCID: PMC6029753 DOI: 10.1371/journal.pone.0199643] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/11/2018] [Indexed: 12/13/2022] Open
Abstract
Neuronal nicotinic acetylcholine receptors (nAChRs) of the cholinergic system have been linked to antinociception, and therefore could be an alternative target for pain alleviation. nAChR activity has been shown to be regulated by the nicotinic modulator, lynx1, which forms stable complexes with nAChRs and has a negative allosteric action on their function. The objective in this study was to investigate the contribution of lynx1 to nicotine-mediated antinociception. Lynx1 contribution was investigated by mRNA expression analysis and electrophysiological responses to nicotine in the dorsal raphe nucleus (DRN), a part of the pain signaling pathway. In vivo antinociception was investigated in a test of nociception, the hot-plate analgesia assay with behavioral pharmacology. Lynx1/α4β2 nAChR interactions were investigated using molecular dynamics computational modeling. Nicotine evoked responses in serotonergic and GABAergic neurons in the DRN are augmented in slices lacking lynx1 (lynx1KO). The antinociceptive effect of nicotine and epibatidine is enhanced in lynx1KO mice and blocked by mecamylamine and DHβE. Computer simulations predict preferential binding affinity of lynx1 to the α:α interface that exists in the stoichiometry of the low sensitivity (α4)3(β2)2 nAChRs. Taken together, these data point to a role of lynx1 in mediating pain signaling in the DRN through preferential affinity to the low sensitivity α4β2 nAChRs. This study suggests that lynx1 is a possible alternative avenue for nociceptive modulation outside of opioid-based strategies.
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Affiliation(s)
- Neel I. Nissen
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
- Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Kristin R. Anderson
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Huaixing Wang
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Hui Sun Lee
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Carly Garrison
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | | | - Kasarah Ackerman
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Wonpil Im
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Julie M. Miwa
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
- * E-mail:
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40
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Bernier L, Ase AR, Séguéla P. P2X receptor channels in chronic pain pathways. Br J Pharmacol 2018; 175:2219-2230. [PMID: 28728214 PMCID: PMC5980614 DOI: 10.1111/bph.13957] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/05/2017] [Accepted: 07/10/2017] [Indexed: 12/18/2022] Open
Abstract
Chronic pain is a highly prevalent debilitating condition for which treatment options remain limited for many patients. Ionotropic ATP signalling through excitatory and calcium-permeable P2X receptor channels is now rightfully considered as a critical player in pathological pain generation and maintenance; therefore, their selective targeting represents a therapeutic opportunity with promising yet untapped potential. Recent advances in the structural, functional and pharmacological characterization of rodent and human ATP-gated P2X receptor channels have shed brighter light on the role of specific subtypes in the pathophysiology of chronic inflammatory, neuropathic or cancer pain. Here, we will review the contribution of P2X3, P2X4 and P2X7 receptors to chronic pain and discuss the opportunities and challenges associated with the pharmacological manipulation of their function. LINKED ARTICLES This article is part of a themed section on Recent Advances in Targeting Ion Channels to Treat Chronic Pain. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.12/issuetoc.
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Affiliation(s)
- Louis‐Philippe Bernier
- Department of Psychiatry, Djavad Mowafaghian Centre for Brain HealthUniversity of British ColumbiaVancouverBCCanada
| | - Ariel R Ase
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, Alan Edwards Centre for Research on PainMcGill UniversityMontréalQCCanada
| | - Philippe Séguéla
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, Alan Edwards Centre for Research on PainMcGill UniversityMontréalQCCanada
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Effect of Human Genetic Variability on Gene Expression in Dorsal Root Ganglia and Association with Pain Phenotypes. Cell Rep 2018; 19:1940-1952. [PMID: 28564610 DOI: 10.1016/j.celrep.2017.05.018] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 02/14/2017] [Accepted: 05/03/2017] [Indexed: 01/08/2023] Open
Abstract
Dorsal root ganglia (DRG) relay sensory information to the brain, giving rise to the perception of pain, disorders of which are prevalent and burdensome. Here, we mapped expression quantitative trait loci (eQTLs) in a collection of human DRGs. DRG eQTLs were enriched within untranslated regions of coding genes of low abundance, with some overlapping with other brain regions and blood cell cis-eQTLs. We confirm functionality of identified eQTLs through their significant enrichment within open chromatin and highly deleterious SNPs, particularly at the exon level, suggesting substantial contribution of eQTLs to alternative splicing regulation. We illustrate pain-related genetic association results explained by DRG eQTLs, with the strongest evidence for contribution of the human leukocyte antigen (HLA) locus, confirmed using a mouse inflammatory pain model. Finally, we show that DRG eQTLs are found among hits in numerous genome-wide association studies, suggesting that this dataset will help address pain components of non-pain disorders.
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Starobova H, S. W. A. H, Lewis RJ, Vetter I. Transcriptomics in pain research: insights from new and old technologies. Mol Omics 2018; 14:389-404. [DOI: 10.1039/c8mo00181b] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Physiological and pathological pain involves a complex interplay of multiple cell types and signaling pathways.
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Affiliation(s)
- H. Starobova
- Centre for Pain Research
- Institute for Molecular Bioscience
- University of Queensland
- St Lucia
- Australia
| | - Himaya S. W. A.
- Centre for Pain Research
- Institute for Molecular Bioscience
- University of Queensland
- St Lucia
- Australia
| | - R. J. Lewis
- Centre for Pain Research
- Institute for Molecular Bioscience
- University of Queensland
- St Lucia
- Australia
| | - I. Vetter
- Centre for Pain Research
- Institute for Molecular Bioscience
- University of Queensland
- St Lucia
- Australia
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43
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Queme LF, Ross JL, Jankowski MP. Peripheral Mechanisms of Ischemic Myalgia. Front Cell Neurosci 2017; 11:419. [PMID: 29311839 PMCID: PMC5743676 DOI: 10.3389/fncel.2017.00419] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/13/2017] [Indexed: 12/18/2022] Open
Abstract
Musculoskeletal pain due to ischemia is present in a variety of clinical conditions including peripheral vascular disease (PVD), sickle cell disease (SCD), complex regional pain syndrome (CRPS), and even fibromyalgia (FM). The clinical features associated with deep tissue ischemia are unique because although the subjective description of pain is common to other forms of myalgia, patients with ischemic muscle pain often respond poorly to conventional analgesic therapies. Moreover, these patients also display increased cardiovascular responses to muscle contraction, which often leads to exercise intolerance or exacerbation of underlying cardiovascular conditions. This suggests that the mechanisms of myalgia development and the role of altered cardiovascular function under conditions of ischemia may be distinct compared to other injuries/diseases of the muscles. It is widely accepted that group III and IV muscle afferents play an important role in the development of pain due to ischemia. These same muscle afferents also form the sensory component of the exercise pressor reflex (EPR), which is the increase in heart rate and blood pressure (BP) experienced after muscle contraction. Studies suggest that afferent sensitization after ischemia depends on interactions between purinergic (P2X and P2Y) receptors, transient receptor potential (TRP) channels, and acid sensing ion channels (ASICs) in individual populations of peripheral sensory neurons. Specific alterations in primary afferent function through these receptor mechanisms correlate with increased pain related behaviors and altered EPRs. Recent evidence suggests that factors within the muscles during ischemic conditions including upregulation of growth factors and cytokines, and microvascular changes may be linked to the overexpression of these different receptor molecules in the dorsal root ganglia (DRG) that in turn modulate pain and sympathetic reflexes. In this review article, we will discuss the peripheral mechanisms involved in the development of ischemic myalgia and the role that primary sensory neurons play in EPR modulation.
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Affiliation(s)
- Luis F Queme
- Department of Anesthesia, Division of Pain Management, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Jessica L Ross
- Department of Anesthesia, Division of Pain Management, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Michael P Jankowski
- Department of Anesthesia, Division of Pain Management, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
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44
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Elnagar MR, Walls AB, Helal GK, Hamada FM, Thomsen MS, Jensen AA. Probing the putative α7 nAChR/NMDAR complex in human and murine cortex and hippocampus: Different degrees of complex formation in healthy and Alzheimer brain tissue. PLoS One 2017; 12:e0189513. [PMID: 29261717 PMCID: PMC5738045 DOI: 10.1371/journal.pone.0189513] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 11/28/2017] [Indexed: 01/20/2023] Open
Abstract
α7 nicotinic acetylcholine receptors (nAChRs) and N-methyl-D-aspartate receptors (NMDARs) are key mediators of central cholinergic and glutamatergic neurotransmission, respectively. In addition to numerous well-established functional interactions between α7 nAChRs and NMDARs, the two receptors have been proposed to form a multimeric complex, and in the present study we have investigated this putative α7 nAChR/NMDAR assembly in human and murine brain tissues. By α-bungarotoxin (BGT) affinity purification, α7 and NMDAR subunits were co-purified from human and murine cortical and hippocampal homogenates, substantiating the notion that the receptors are parts of a multimeric complex in the human and rodent brain. Interestingly, the ratios between GluN1 and α7 levels in BGT pull-downs from cortical homogenates from Alzheimer's disease (AD) brains were significantly lower than those in pull-downs from non-AD controls, indicating a reduced degree of α7 nAChR/NMDAR complex formation in the diseased tissue. A similar difference in GluN1/α7 ratios was observed between pull-downs from cortical homogenates from adult 3xTg-AD and age-matched wild type (WT) mice, whereas the GluN1/α7 ratios determined in pull-downs from young 3xTg-AD and age-matched WT mice did not differ significantly. The observation that pretreatment with oligomeric amyloid-β1-42 reduced GluN1/α7 ratios in BGT pull-downs from human cortical homogenate in a concentration-dependent manner provided a plausible molecular mechanism for this observed reduction. In conclusion, while it will be important to further challenge the existence of the putative α7 nAChR/NMDAR complex in future studies applying other methodologies than biochemical assays and to investigate the functional implications of this complex for cholinergic and glutamatergic neurotransmission, this work supports the formation of the complex and presents new insights into its regulation in healthy and diseased brain tissue.
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Affiliation(s)
- Mohamed R. Elnagar
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken, Copenhagen Ø, Denmark
- Faculty of Pharmacy, Al-Azhar University, Al-Mokhaym Al-Daem, Nasr City, Cairo, Egypt
| | - Anne Byriel Walls
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken, Copenhagen Ø, Denmark
| | - Gouda K. Helal
- Faculty of Pharmacy, Al-Azhar University, Al-Mokhaym Al-Daem, Nasr City, Cairo, Egypt
| | - Farid M. Hamada
- Faculty of Pharmacy, Al-Azhar University, Al-Mokhaym Al-Daem, Nasr City, Cairo, Egypt
| | - Morten Skøtt Thomsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken, Copenhagen Ø, Denmark
| | - Anders A. Jensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken, Copenhagen Ø, Denmark
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45
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Hone AJ, McIntosh JM. Nicotinic acetylcholine receptors in neuropathic and inflammatory pain. FEBS Lett 2017; 592:1045-1062. [PMID: 29030971 DOI: 10.1002/1873-3468.12884] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 09/22/2017] [Accepted: 10/05/2017] [Indexed: 01/11/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) are actively being investigated as therapeutic targets for the treatment of pain and inflammation, but despite more than 30 years of research, there are currently no FDA-approved analgesics that are specific for these receptors. Much of the initial research effort focused on the α4β2 nAChR subtype, but more recently, additional subtypes have been identified as promising new leads and include α6β4, α7, and α9-containing nAChRs. This Review will focus on the distribution of these nAChRs in the cell types involved in neuropathic pain and inflammation and the activity of currently available nicotinic ligands.
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Affiliation(s)
- Arik J Hone
- Department of Biology, University of Utah, Salt Lake City, UT, USA
| | - J Michael McIntosh
- Department of Biology, University of Utah, Salt Lake City, UT, USA.,Department of Psychiatry, University of Utah, Salt Lake City, UT, USA.,George E. Whalen Veterans Affairs Medical Center, Salt Lake City, UT, USA
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Wall TR, Henderson BJ, Voren G, Wageman CR, Deshpande P, Cohen BN, Grady SR, Marks MJ, Yohannes D, Kenny PJ, Bencherif M, Lester HA. TC299423, a Novel Agonist for Nicotinic Acetylcholine Receptors. Front Pharmacol 2017; 8:641. [PMID: 29033834 PMCID: PMC5626944 DOI: 10.3389/fphar.2017.00641] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Accepted: 08/29/2017] [Indexed: 01/11/2023] Open
Abstract
(E)-5-(Pyrimidin-5-yl)-1,2,3,4,7,8-hexahydroazocine (TC299423) is a novel agonist for nicotinic acetylcholine receptors (nAChRs). We examined its efficacy, affinity, and potency for α6β2∗ (α6β2-containing), α4β2∗, and α3β4∗ nAChRs, using [125I]-epibatidine binding, whole-cell patch-clamp recordings, synaptosomal 86Rb+ efflux, [3H]-dopamine release, and [3H]-acetylcholine release. TC299423 displayed an EC50 of 30–60 nM for α6β2∗ nAChRs in patch-clamp recordings and [3H]-dopamine release assays. Its potency for α6β2∗ in these assays was 2.5-fold greater than that for α4β2∗, and much greater than that for α3β4∗-mediated [3H]-acetylcholine release. We observed no major off-target binding on 70 diverse molecular targets. TC299423 was bioavailable after intraperitoneal or oral administration. Locomotor assays, measured with gain-of-function, mutant α6 (α6L9′S) nAChR mice, show that TC299423 elicits α6β2∗ nAChR-mediated responses at low doses. Conditioned place preference assays show that low-dose TC299423 also produces significant reward in α6L9′S mice, and modest reward in WT mice, through a mechanism that probably involves α6(non-α4)β2∗ nAChRs. However, TC299423 did not suppress nicotine self-administration in rats, indicating that it did not block nicotine reinforcement in the dosage range that was tested. In a hot-plate test, TC299423 evoked antinociceptive responses in mice similar to those of nicotine. TC299423 and nicotine similarly inhibited mouse marble burying as a measure of anxiolytic effects. Taken together, our data suggest that TC299423 will be a useful small-molecule agonist for future in vitro and in vivo studies of nAChR function and physiology.
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Affiliation(s)
- Teagan R Wall
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Brandon J Henderson
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, United States
| | - George Voren
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Charles R Wageman
- Institute of Behavioral Genetics, University of Colorado, Boulder, Boulder, CO, United States
| | - Purnima Deshpande
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Bruce N Cohen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Sharon R Grady
- Institute of Behavioral Genetics, University of Colorado, Boulder, Boulder, CO, United States
| | - Michael J Marks
- Institute of Behavioral Genetics, University of Colorado, Boulder, Boulder, CO, United States.,Department of Psychology and Neuroscience, University of Colorado, Boulder, Boulder, CO, United States
| | | | - Paul J Kenny
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | | | - Henry A Lester
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
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Zakrzewicz A, Richter K, Agné A, Wilker S, Siebers K, Fink B, Krasteva-Christ G, Althaus M, Padberg W, Hone AJ, McIntosh JM, Grau V. Canonical and Novel Non-Canonical Cholinergic Agonists Inhibit ATP-Induced Release of Monocytic Interleukin-1β via Different Combinations of Nicotinic Acetylcholine Receptor Subunits α7, α9 and α10. Front Cell Neurosci 2017; 11:189. [PMID: 28725182 PMCID: PMC5496965 DOI: 10.3389/fncel.2017.00189] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 06/20/2017] [Indexed: 12/22/2022] Open
Abstract
Recently, we discovered a cholinergic mechanism that inhibits the adenosine triphosphate (ATP)-dependent release of interleukin-1β (IL-1β) by human monocytes via nicotinic acetylcholine receptors (nAChRs) composed of α7, α9 and/or α10 subunits. Furthermore, we identified phosphocholine (PC) and dipalmitoylphosphatidylcholine (DPPC) as novel nicotinic agonists that elicit metabotropic activity at monocytic nAChR. Interestingly, PC does not provoke ion channel responses at conventional nAChRs composed of subunits α9 and α10. The purpose of this study is to determine the composition of nAChRs necessary for nicotinic signaling in monocytic cells and to test the hypothesis that common metabolites of phosphatidylcholines, lysophosphatidylcholine (LPC) and glycerophosphocholine (G-PC), function as nAChR agonists. In peripheral blood mononuclear cells from nAChR gene-deficient mice, we demonstrated that inhibition of ATP-dependent release of IL-1β by acetylcholine (ACh), nicotine and PC depends on subunits α7, α9 and α10. Using a panel of nAChR antagonists and siRNA technology, we confirmed the involvement of these subunits in the control of IL-1β release in the human monocytic cell line U937. Furthermore, we showed that LPC (C16:0) and G-PC efficiently inhibit ATP-dependent release of IL-1β. Of note, the inhibitory effects mediated by LPC and G-PC depend on nAChR subunits α9 and α10, but only to a small degree on α7. In Xenopuslaevis oocytes heterologously expressing different combinations of human α7, α9 or α10 subunits, ACh induced canonical ion channel activity, whereas LPC, G-PC and PC did not. In conclusion, we demonstrate that canonical nicotinic agonists and PC elicit metabotropic nAChR activity in monocytes via interaction of nAChR subunits α7, α9 and α10. For the metabotropic signaling of LPC and G-PC, nAChR subunits α9 and α10 are needed, whereas α7 is virtually dispensable. Furthermore, molecules bearing a PC group in general seem to regulate immune functions without perturbing canonical ion channel functions of nAChR.
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Affiliation(s)
- Anna Zakrzewicz
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University GiessenGiessen, Germany
| | - Katrin Richter
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University GiessenGiessen, Germany
| | - Alisa Agné
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University GiessenGiessen, Germany
| | - Sigrid Wilker
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University GiessenGiessen, Germany
| | - Kathrin Siebers
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University GiessenGiessen, Germany
| | - Bijan Fink
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University GiessenGiessen, Germany
| | - Gabriela Krasteva-Christ
- Institute of Anatomy and Cell Biology, Justus-Liebig-University GiessenGiessen, Germany.,Institute of Anatomy and Cell Biology, Saarland UniversityHomburg, Germany.,Member of the German Centre for Lung ResearchGiessen, Germany
| | - Mike Althaus
- Institute of Animal Physiology, Justus-Liebig-University GiessenGiessen, Germany.,School of Biology, Newcastle UniversityNewcastle upon Tyne, United Kingdom
| | - Winfried Padberg
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University GiessenGiessen, Germany
| | - Arik J Hone
- Department of Biology, University of UtahSalt Lake City, UT, United States
| | - J Michael McIntosh
- Department of Biology, University of UtahSalt Lake City, UT, United States.,George E. Wahlen Veterans Affairs Medical CenterSalt Lake City, UT, United States.,Department of Psychiatry, University of UtahSalt Lake City, UT, United States
| | - Veronika Grau
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University GiessenGiessen, Germany.,Member of the German Centre for Lung ResearchGiessen, Germany
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48
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Mohammadi SA, Burton TJ, Christie MJ. α9-nAChR knockout mice exhibit dysregulation of stress responses, affect and reward-related behaviour. Behav Brain Res 2017; 328:105-114. [PMID: 28408300 DOI: 10.1016/j.bbr.2017.04.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 03/30/2017] [Accepted: 04/01/2017] [Indexed: 10/19/2022]
Abstract
The α9α10-subtype of nicotinic acetylcholine receptor (nAChR) has recently garnered interest in biomedicine and is being pursued as an analgesic target. However, the receptor exhibits diverse tissue distribution, the function of which is known to varying degrees, and targeting this receptor for clinical treatments without a broad understanding of its function may have adverse consequences. The α9α10-nAChR is expressed in the adrenal and pituitary glands, suggesting a potential role in the stress response, but little is known about its function in this tissue. Here we determined a role for the α9α10-nAChR in behavioural and physiological stress responses, by comparing the stress- and affect-related phenotypes of wildtype and α9-nAChR knockout mice. Naïve knockout mice exhibited largely normal behaviour on standard tests of affective behaviour. However, after sub-chronic restraint stress knockout mice showed significantly decreased stress-induced arousal and increased anxiety-like behaviour when compared to wildtype animals. Physiologically, corticosterone responses were muted in knockout mice after an acute stressor, but exaggerated in response to the same stressor after undergoing sub-chronic stress. Behavioural profiling of the α9-nAChR knockout mice in the home-cage revealed that circadian patterns of activity were altered when compared to wildtype controls. Furthermore, knockout mice showed altered responses to a period of reward discounting, resulting in anhedonia-like behaviour in a sucrose preference test where WT mice continued to seek reward. These experiments uncover a novel role for the α9α10-nAChR in mounting a normal stress response and in the regulation of affective- and reward-related behaviour, and suggest that pursuing the receptor for clinical treatments may not be as straightforward as has been suggested.
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Affiliation(s)
- Sarasa A Mohammadi
- Discipline of Pharmacology, The University of Sydney, Sydney, NSW 2006, Australia.
| | - Thomas J Burton
- Animal Behavioural Facility, Bosch Institute, The University of Sydney, Sydney, NSW 2006, Australia.
| | - MacDonald J Christie
- Discipline of Pharmacology, The University of Sydney, Sydney, NSW 2006, Australia.
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49
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Descalzi G, Mitsi V, Purushothaman I, Gaspari S, Avrampou K, Loh YHE, Shen L, Zachariou V. Neuropathic pain promotes adaptive changes in gene expression in brain networks involved in stress and depression. Sci Signal 2017; 10:10/471/eaaj1549. [PMID: 28325815 DOI: 10.1126/scisignal.aaj1549] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Neuropathic pain is a complex chronic condition characterized by various sensory, cognitive, and affective symptoms. A large percentage of patients with neuropathic pain are also afflicted with depression and anxiety disorders, a pattern that is also seen in animal models. Furthermore, clinical and preclinical studies indicate that chronic pain corresponds with adaptations in several brain networks involved in mood, motivation, and reward. Chronic stress is also a major risk factor for depression. We investigated whether chronic pain and stress affect similar molecular mechanisms and whether chronic pain can affect gene expression patterns that are involved in depression. Using two mouse models of neuropathic pain and depression [spared nerve injury (SNI) and chronic unpredictable stress (CUS)], we performed next-generation RNA sequencing and pathway analysis to monitor changes in gene expression in the nucleus accumbens (NAc), the medial prefrontal cortex (mPFC), and the periaqueductal gray (PAG). In addition to finding unique transcriptome profiles across these regions, we identified a substantial number of signaling pathway-associated genes with similar changes in expression in both SNI and CUS mice. Many of these genes have been implicated in depression, anxiety, and chronic pain in patients. Our study provides a resource of the changes in gene expression induced by long-term neuropathic pain in three distinct brain regions and reveals molecular connections between pain and chronic stress.
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Affiliation(s)
- Giannina Descalzi
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Vasiliki Mitsi
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Immanuel Purushothaman
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Sevasti Gaspari
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Kleopatra Avrampou
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yong-Hwee Eddie Loh
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Li Shen
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Venetia Zachariou
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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50
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Post MR, Lester HA, Dougherty DA. Probing for and Quantifying Agonist Hydrogen Bonds in α6β2 Nicotinic Acetylcholine Receptors. Biochemistry 2017; 56:1836-1840. [PMID: 28287260 DOI: 10.1021/acs.biochem.7b00213] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Designing subtype-selective agonists for neuronal nicotinic acetylcholine receptors is a challenging and significant goal aided by intricate knowledge of each subtype's binding patterns. We previously reported that in α6β2 receptors, acetylcholine makes a functional cation-π interaction with Trp149, but nicotine and TC299423 do not, suggesting a distinctive binding site. This work explores hydrogen binding at the backbone carbonyl associated with α6β2 Trp149. Substituting residue i + 1, Thr150, with its α-hydroxy analogue (Tah) attenuates the carbonyl's hydrogen bond accepting ability. At α6(T150Tah)β2, nicotine shows a 24-fold loss of function, TC299423 shows a modest loss, and acetylcholine shows no effect. Nicotine was further analyzed via a double-mutant cycle analysis utilizing N'-methylnicotinium, which indicated a hydrogen bond in α6β2 with a ΔΔG of 2.6 kcal/mol. Thus, even though nicotine does not make the conserved cation-π interaction with Trp149, it still makes a functional hydrogen bond to its associated backbone carbonyl.
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Affiliation(s)
- Michael R Post
- Division of Chemistry and Chemical Engineering and ‡Division of Biology and Biological Engineering, California Institute of Technology , Pasadena, California 91125, United States
| | - Henry A Lester
- Division of Chemistry and Chemical Engineering and ‡Division of Biology and Biological Engineering, California Institute of Technology , Pasadena, California 91125, United States
| | - Dennis A Dougherty
- Division of Chemistry and Chemical Engineering and ‡Division of Biology and Biological Engineering, California Institute of Technology , Pasadena, California 91125, United States
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