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Lee KH, Kim UJ, Cha M, Lee BH. Inhibiting Nav1.7 channels in pulpitis: An in vivo study on neuronal hyperexcitability. Biochem Biophys Res Commun 2024; 717:150044. [PMID: 38718567 DOI: 10.1016/j.bbrc.2024.150044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 04/30/2024] [Indexed: 05/21/2024]
Abstract
Pulpitis constitutes a significant challenge in clinical management due to its impact on peripheral nerve tissue and the persistence of chronic pain. Despite its clinical importance, the correlation between neuronal activity and the expression of voltage-gated sodium channel 1.7 (Nav1.7) in the trigeminal ganglion (TG) during pulpitis is less investigated. The aim of this study was to examine the relationship between experimentally induced pulpitis and Nav1.7 expression in the TG and to investigate the potential of selective Nav1.7 modulation to attenuate TG abnormal activity associated with pulpitis. Acute pulpitis was induced at the maxillary molar (M1) using allyl isothiocyanate (AITC). The mice were divided into three groups: control, pulpitis model, and pulpitis model treated with ProTx-II, a selective Nav1.7 channel inhibitor. After three days following the surgery, we conducted a recording and comparative analysis of the neural activity of the TG utilizing in vivo optical imaging. Then immunohistochemistry and Western blot were performed to assess changes in the expression levels of extracellular signal-regulated kinase (ERK), c-Fos, collapsin response mediator protein-2 (CRMP2), and Nav1.7 channels. The optical imaging result showed significant neurological excitation in pulpitis TGs. Nav1.7 expressions exhibited upregulation, accompanied by signaling molecular changes suggestive of inflammation and neuroplasticity. In addition, inhibition of Nav1.7 led to reduced neural activity and subsequent decreases in ERK, c-Fos, and CRMP2 levels. These findings suggest the potential for targeting overexpressed Nav1.7 channels to alleviate pain associated with pulpitis, providing practical pain management strategies.
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Affiliation(s)
- Kyung Hee Lee
- Department of Dental Hygiene, Division of Health Science, Dongseo University, Busan, 47011, Republic of Korea
| | - Un Jeng Kim
- Department of Physiology, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Myeounghoon Cha
- Department of Physiology, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
| | - Bae Hwan Lee
- Department of Physiology, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea; Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
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2
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Liu Y, Balaji R, de Toledo MAS, Ernst S, Hautvast P, Kesdoğan AB, Körner J, Zenke M, Neureiter A, Lampert A. The pain target Na V1.7 is expressed late during human iPS cell differentiation into sensory neurons as determined in high-resolution imaging. Pflugers Arch 2024; 476:975-992. [PMID: 38538988 PMCID: PMC11139713 DOI: 10.1007/s00424-024-02945-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/16/2024] [Accepted: 03/11/2024] [Indexed: 06/01/2024]
Abstract
Human-induced pluripotent stem cells (iPS cells) are efficiently differentiated into sensory neurons. These cells express the voltage-gated sodium channel NaV1.7, which is a validated pain target. NaV1.7 deficiency leads to pain insensitivity, whereas NaV1.7 gain-of-function mutants are associated with chronic pain. During differentiation, the sensory neurons start spontaneous action potential firing around day 22, with increasing firing rate until day 40. Here, we used CRISPR/Cas9 genome editing to generate a HA-tag NaV1.7 to follow its expression during differentiation. We used two protocols to generate sensory neurons: the classical small molecule approach and a directed differentiation methodology and assessed surface NaV1.7 expression by Airyscan high-resolution microscopy. Our results show that maturation of at least 49 days is necessary to observe robust NaV1.7 surface expression in both protocols. Electric activity of the sensory neurons precedes NaV1.7 surface expression. A clinically effective NaV1.7 blocker is still missing, and we expect this iPS cell model system to be useful for drug discovery and disease modeling.
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Affiliation(s)
- Yi Liu
- Institute of Neurophysiology, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Rachna Balaji
- Institute of Neurophysiology, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Marcelo A Szymanski de Toledo
- Department of Hematology, Oncology, and Stem Cell Transplantation, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Sabrina Ernst
- Confocal Microscopy Facility, Interdisciplinary Center for Clinical Research IZKF, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Petra Hautvast
- Institute of Neurophysiology, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Aylin B Kesdoğan
- Institute of Neurophysiology, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Jannis Körner
- Institute of Neurophysiology, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
- Department of Anaesthesiology, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
- Department of Intensive and Intermediate Care, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
- Scientific Center for Neuropathic Pain Research Aachen, SCN-Aachen Uniklinik RWTH Aachen, Aachen, Germany
| | - Martin Zenke
- Department of Hematology, Oncology, and Stem Cell Transplantation, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Anika Neureiter
- Institute of Neurophysiology, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany.
| | - Angelika Lampert
- Institute of Neurophysiology, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen, Germany.
- Scientific Center for Neuropathic Pain Research Aachen, SCN-Aachen Uniklinik RWTH Aachen, Aachen, Germany.
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3
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de Cássia Collaço R, Lammens M, Blevins C, Rodgers K, Gurau A, Yamauchi S, Kim C, Forrester J, Liu E, Ha J, Mei Y, Boehm C, Wohler E, Sobreira N, Rowe PC, Valle D, Brock MV, Bosmans F. Anxiety and dysautonomia symptoms in patients with a Na V1.7 mutation and the potential benefits of low-dose short-acting guanfacine. Clin Auton Res 2024; 34:191-201. [PMID: 38064009 DOI: 10.1007/s10286-023-01004-1] [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: 09/05/2023] [Accepted: 11/15/2023] [Indexed: 03/17/2024]
Abstract
PURPOSE Guanfacine is an α2A-adrenergic receptor agonist, FDA-approved to treat attention-deficit hyperactivity disorder and high blood pressure, typically as an extended-release formulation up to 7 mg/day. In our dysautonomia clinic, we observed that off-label use of short-acting guanfacine at 1 mg/day facilitated symptom relief in two families with multiple members presenting with severe generalized anxiety. We also noted anecdotal improvements in associated dysautonomia symptoms such as hyperhidrosis, cognitive impairment, and palpitations. We postulated that a genetic deficit existed in these patients that might augment guanfacine susceptibility. METHODS We used whole-exome sequencing to identify mutations in patients with shared generalized anxiety and dysautonomia symptoms. Guanfacine-induced changes in the function of voltage-gated Na+ channels were investigated using voltage-clamp electrophysiology. RESULTS Whole-exome sequencing uncovered the p.I739V mutation in SCN9A in the proband of two nonrelated families. Moreover, guanfacine inhibited ionic currents evoked by wild-type and mutant NaV1.7 encoded by SCN9A, as well as other NaV channel subtypes to a varying degree. CONCLUSION Our study provides further evidence for a possible pathophysiological role of NaV1.7 in anxiety and dysautonomia. Combined with off-target effects on NaV channel function, daily administration of 1 mg short-acting guanfacine may be sufficient to normalize NaV channel mutation-induced changes in sympathetic activity, perhaps aided by partial inhibition of NaV1.7 or other channel subtypes. In a broader context, expanding genetic and functional data about ion channel aberrations may enable the prospect of stratifying patients in which mutation-induced increased sympathetic tone normalization by guanfacine can support treatment strategies for anxiety and dysautonomia symptoms.
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Affiliation(s)
- Rita de Cássia Collaço
- Molecular Physiology and Neurophysics Group, Department of Basic and Applied Medical Sciences, University of Ghent, Ghent, Belgium
| | - Maxime Lammens
- Molecular Physiology and Neurophysics Group, Department of Basic and Applied Medical Sciences, University of Ghent, Ghent, Belgium
| | - Carley Blevins
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Kristen Rodgers
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Andrei Gurau
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Suguru Yamauchi
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Christine Kim
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Jeannine Forrester
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Edward Liu
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Jinny Ha
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Yuping Mei
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Corrine Boehm
- McKusick-Nathans Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Elizabeth Wohler
- McKusick-Nathans Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Nara Sobreira
- McKusick-Nathans Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Peter C Rowe
- Department of Pediatrics, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - David Valle
- McKusick-Nathans Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Malcolm V Brock
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
| | - Frank Bosmans
- Molecular Physiology and Neurophysics Group, Department of Basic and Applied Medical Sciences, University of Ghent, Ghent, Belgium.
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Li AH, Kuo YY, Yang SB, Chen PC. Central Channelopathies in Obesity. CHINESE J PHYSIOL 2024; 67:15-26. [PMID: 38780269 DOI: 10.4103/ejpi.ejpi-d-23-00029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 01/18/2024] [Indexed: 05/25/2024] Open
Abstract
As obesity has raised heightening awareness, researchers have attempted to identify potential targets that can be treated for therapeutic intervention. Focusing on the central nervous system (CNS), the key organ in maintaining energy balance, a plethora of ion channels that are expressed in the CNS have been inspected and determined through manipulation in different hypothalamic neural subpopulations for their roles in fine-tuning neuronal activity on energy state alterations, possibly acting as metabolic sensors. However, a remaining gap persists between human clinical investigations and mouse studies. Despite having delineated the pathways and mechanisms of how the mouse study-identified ion channels modulate energy homeostasis, only a few targets overlap with the obesity-related risk genes extracted from human genome-wide association studies. Here, we present the most recently discovered CNS-specific metabolism-correlated ion channels using reverse and forward genetics approaches in mice and humans, respectively, in the hope of illuminating the prospects for future therapeutic development.
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Affiliation(s)
- Athena Hsu Li
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yi-Ying Kuo
- Department of Physiology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Shi-Bing Yang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Pei-Chun Chen
- Department of Physiology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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5
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Brüning JC, Fenselau H. Integrative neurocircuits that control metabolism and food intake. Science 2023; 381:eabl7398. [PMID: 37769095 DOI: 10.1126/science.abl7398] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 08/31/2023] [Indexed: 09/30/2023]
Abstract
Systemic metabolism has to be constantly adjusted to the variance of food intake and even be prepared for anticipated changes in nutrient availability. Therefore, the brain integrates multiple homeostatic signals with numerous cues that predict future deviations in energy supply. Recently, our understanding of the neural pathways underlying these regulatory principles-as well as their convergence in the hypothalamus as the key coordinator of food intake, energy expenditure, and glucose metabolism-have been revealed. These advances have changed our view of brain-dependent control of metabolic physiology. In this Review, we discuss new concepts about how alterations in these pathways contribute to the development of prevalent metabolic diseases such as obesity and type 2 diabetes mellitus and how this emerging knowledge may provide new targets for their treatment.
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Affiliation(s)
- Jens C Brüning
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, 50931 Cologne, Germany
- Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, 50924 Cologne, Germany
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
- National Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Henning Fenselau
- Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, 50924 Cologne, Germany
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
- Research Group Synaptic Transmission in Energy Homeostasis, Max Planck Institute for Metabolism Research, 50931 Cologne, Germany
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6
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Valtcheva S, Issa HA, Bair-Marshall CJ, Martin KA, Jung K, Zhang Y, Kwon HB, Froemke RC. Neural circuitry for maternal oxytocin release induced by infant cries. Nature 2023; 621:788-795. [PMID: 37730989 PMCID: PMC10639004 DOI: 10.1038/s41586-023-06540-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 08/15/2023] [Indexed: 09/22/2023]
Abstract
Oxytocin is a neuropeptide that is important for maternal physiology and childcare, including parturition and milk ejection during nursing1-6. Suckling triggers the release of oxytocin, but other sensory cues-specifically, infant cries-can increase the levels of oxytocin in new human mothers7, which indicates that cries can activate hypothalamic oxytocin neurons. Here we describe a neural circuit that routes auditory information about infant vocalizations to mouse oxytocin neurons. We performed in vivo electrophysiological recordings and photometry from identified oxytocin neurons in awake maternal mice that were presented with pup calls. We found that oxytocin neurons responded to pup vocalizations, but not to pure tones, through input from the posterior intralaminar thalamus, and that repetitive thalamic stimulation induced lasting disinhibition of oxytocin neurons. This circuit gates central oxytocin release and maternal behaviour in response to calls, providing a mechanism for the integration of sensory cues from the offspring in maternal endocrine networks to ensure modulation of brain state for efficient parenting.
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Affiliation(s)
- Silvana Valtcheva
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA.
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA.
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA.
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA.
- Center for Neural Science, New York University, New York, NY, USA.
| | - Habon A Issa
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
- Center for Neural Science, New York University, New York, NY, USA
| | - Chloe J Bair-Marshall
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
- Center for Neural Science, New York University, New York, NY, USA
| | - Kathleen A Martin
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
- Center for Neural Science, New York University, New York, NY, USA
| | - Kanghoon Jung
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yiyao Zhang
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA
| | - Hyung-Bae Kwon
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert C Froemke
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA.
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA.
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA.
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA.
- Center for Neural Science, New York University, New York, NY, USA.
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7
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Zhang SX, Kim A, Madara JC, Zhu PK, Christenson LF, Lutas A, Kalugin PN, Jin Y, Pal A, Tian L, Lowell BB, Andermann ML. Competition between stochastic neuropeptide signals calibrates the rate of satiation. RESEARCH SQUARE 2023:rs.3.rs-3185572. [PMID: 37546985 PMCID: PMC10402269 DOI: 10.21203/rs.3.rs-3185572/v1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
We investigated how transmission of hunger- and satiety-promoting neuropeptides, NPY and αMSH, is integrated at the level of intracellular signaling to control feeding. Receptors for these peptides use the second messenger cAMP. How cAMP integrates opposing peptide signals to regulate energy balance, and the in vivo spatiotemporal dynamics of endogenous peptidergic signaling, remain largely unknown. We show that AgRP axon stimulation in the paraventricular hypothalamus evokes probabilistic NPY release that triggers stochastic cAMP decrements in downstream MC4R-expressing neurons (PVHMC4R). Meanwhile, POMC axon stimulation triggers stochastic, αMSH-dependent cAMP increments. Release of either peptide impacts a ~100 μm diameter region, and when these peptide signals overlap, they compete to control cAMP. The competition is reflected by hunger-state-dependent differences in the amplitude and persistence of cAMP transients: hunger peptides are more efficacious in the fasted state, satiety peptides in the fed state. Feeding resolves the competition by simultaneously elevating αMSH release and suppressing NPY release, thereby sustaining elevated cAMP in PVHMC4R neurons. In turn, cAMP potentiates feeding-related excitatory inputs and promotes satiation across minutes. Our findings highlight how biochemical integration of opposing, quantal peptide signals during energy intake orchestrates a gradual transition between stable states of hunger and satiety.
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Affiliation(s)
- Stephen X Zhang
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Co-corresponding authors
| | - Angela Kim
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Joseph C Madara
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Paula K Zhu
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Lauren F Christenson
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Andrew Lutas
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Present address: Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Peter N Kalugin
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Program in Neuroscience, Harvard University, Cambridge, MA 02138, USA
| | - Yihan Jin
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Akash Pal
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Lin Tian
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Bradford B Lowell
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Mark L Andermann
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Program in Neuroscience, Harvard University, Cambridge, MA 02138, USA
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- Co-corresponding authors
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8
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Zhang SX, Kim A, Madara JC, Zhu PK, Christenson LF, Lutas A, Kalugin PN, Jin Y, Pal A, Tian L, Lowell BB, Andermann ML. Competition between stochastic neuropeptide signals calibrates the rate of satiation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.11.548551. [PMID: 37503012 PMCID: PMC10369917 DOI: 10.1101/2023.07.11.548551] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
We investigated how transmission of hunger- and satiety-promoting neuropeptides, NPY and αMSH, is integrated at the level of intracellular signaling to control feeding. Receptors for these peptides use the second messenger cAMP, but the messenger's spatiotemporal dynamics and role in energy balance are controversial. We show that AgRP axon stimulation in the paraventricular hypothalamus evokes probabilistic and spatially restricted NPY release that triggers stochastic cAMP decrements in downstream MC4R-expressing neurons (PVH MC4R ). Meanwhile, POMC axon stimulation triggers stochastic, αMSH-dependent cAMP increments. NPY and αMSH competitively control cAMP, as reflected by hunger-state-dependent differences in the amplitude and persistence of cAMP transients evoked by each peptide. During feeding bouts, elevated αMSH release and suppressed NPY release cooperatively sustain elevated cAMP in PVH MC4R neurons, thereby potentiating feeding-related excitatory inputs and promoting satiation across minutes. Our findings highlight how state-dependent integration of opposing, quantal peptidergic events by a common biochemical target calibrates energy intake.
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9
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Zhu J, Lu J, Shen X, He Y, Xia H, Li W, Guo H, Zhang J, Fan X. SCN1A Polymorphisms and Haplotypes Are Associated With Valproic Acid Treatment Outcomes in Chinese Children With Epilepsy. Pediatr Neurol 2023; 146:55-64. [PMID: 37451178 DOI: 10.1016/j.pediatrneurol.2023.06.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 04/20/2023] [Accepted: 06/12/2023] [Indexed: 07/18/2023]
Abstract
BACKGROUND Sodium channel genes, especially SCN1A, were reported to play an important role in the treatment outcomes of antiseizure medications. The aim of this study was to explore the association of SCN1A polymorphisms with efficacy and adverse drug reactions (ADRs) related to valproic acid (VPA) among Chinese children with epilepsy. METHODS A total of 126 children with epilepsy treated with VPA for at least 12 months were enrolled in this study. Three single nucleotide polymorphisms (SNPs) of SCN1A including rs2298771, rs10167228, and rs3812718 were genotyped using Sequenom MassArray system. Bioinformatics tools were used to explore the potential targets and pathways of SCN1A in VPA-related ADRs. RESULTS The three SNPs in this study were found to be closely associated with treatment outcomes for VPA. Carriers of SCN1A rs3812718 TT genotype tended to be seizure-free with VPA treatment (P = 0.007). AA genotype of rs10167228 and TT genotype of rs2298771 might be protective factors for weight gain induced by VPA, whereas TA genotype of rs10167228 and CT genotype of rs2298771 increased the risk. TAT haplotype carriers were found to respond better to VPA treatment (P = 0.017), whereas CTC haplotype might be a risk factor for VPA-induced weight gain (P = 0.035). Bioinformatics analysis suggested that SCN1A might play a role in VPA-induced weight gain by regulating gated channel activity and GABAergic synapse pathway. CONCLUSION This study revealed that SCN1A rs2298771, rs10167228, and rs3812718 polymorphisms and haplotypes might affect the treatment outcomes of VPA in Chinese children with epilepsy.
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Affiliation(s)
- Jiahao Zhu
- Department of Pharmacy, Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, Guangdong, China; Department of Clinical Pharmacology, College of Pharmacy, Jinan University, Guangzhou, Guangdong, China
| | - Jieluan Lu
- Department of Clinical Pharmacology, College of Pharmacy, Jinan University, Guangzhou, Guangdong, China
| | - Xianhuan Shen
- Department of Pharmacy, Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, Guangdong, China; Department of Clinical Pharmacology, College of Pharmacy, Jinan University, Guangzhou, Guangdong, China
| | - Yaodong He
- Department of Pharmacy, Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, Guangdong, China; Department of Clinical Pharmacology, College of Pharmacy, Jinan University, Guangzhou, Guangdong, China
| | - Hanbing Xia
- Department of Pharmacy, Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, Guangdong, China
| | - Wenzhou Li
- Department of Pharmacy, Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, Guangdong, China
| | - Huijuan Guo
- Department of Pharmacy, Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, Guangdong, China
| | - Jianping Zhang
- Department of Clinical Pharmacology, College of Pharmacy, Jinan University, Guangzhou, Guangdong, China.
| | - Xiaomei Fan
- Department of Pharmacy, Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, Guangdong, China.
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10
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Fang X, Chen Y, Wang J, Zhang Z, Bai Y, Denney K, Gan L, Guo M, Weintraub NL, Lei Y, Lu XY. Increased intrinsic and synaptic excitability of hypothalamic POMC neurons underlies chronic stress-induced behavioral deficits. Mol Psychiatry 2023; 28:1365-1382. [PMID: 36473997 PMCID: PMC10005948 DOI: 10.1038/s41380-022-01872-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 10/26/2022] [Accepted: 11/03/2022] [Indexed: 12/12/2022]
Abstract
Chronic stress exposure induces maladaptive behavioral responses and increases susceptibility to neuropsychiatric conditions. However, specific neuronal populations and circuits that are highly sensitive to stress and trigger maladaptive behavioral responses remain to be identified. Here we investigate the patterns of spontaneous activity of proopiomelanocortin (POMC) neurons in the arcuate nucleus (ARC) of the hypothalamus following exposure to chronic unpredictable stress (CUS) for 10 days, a stress paradigm used to induce behavioral deficits such as anhedonia and behavioral despair [1, 2]. CUS exposure increased spontaneous firing of POMC neurons in both male and female mice, attributable to reduced GABA-mediated synaptic inhibition and increased intrinsic neuronal excitability. While acute activation of POMC neurons failed to induce behavioral changes in non-stressed mice of both sexes, subacute (3 days) and chronic (10 days) repeated activation of POMC neurons was sufficient to induce anhedonia and behavioral despair in males but not females under non-stress conditions. Acute activation of POMC neurons promoted susceptibility to subthreshold unpredictable stress in both male and female mice. Conversely, acute inhibition of POMC neurons was sufficient to reverse CUS-induced anhedonia and behavioral despair in both sexes. Collectively, these results indicate that chronic stress induces both synaptic and intrinsic plasticity of POMC neurons, leading to neuronal hyperactivity. Our findings suggest that POMC neuron dysfunction drives chronic stress-related behavioral deficits.
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Affiliation(s)
- Xing Fang
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Yuting Chen
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Jiangong Wang
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Ziliang Zhang
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Yu Bai
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Kirstyn Denney
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Lin Gan
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Ming Guo
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Neal L Weintraub
- Department of Medicine, Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Yun Lei
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Xin-Yun Lu
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, GA, USA.
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11
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Structural basis for Na V1.7 inhibition by pore blockers. Nat Struct Mol Biol 2022; 29:1208-1216. [PMID: 36424527 DOI: 10.1038/s41594-022-00860-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 10/11/2022] [Indexed: 11/26/2022]
Abstract
Voltage-gated sodium channel NaV1.7 plays essential roles in pain and odor perception. NaV1.7 variants cause pain disorders. Accordingly, NaV1.7 has elicited extensive attention in developing new analgesics. Here we present cryo-EM structures of human NaV1.7/β1/β2 complexed with inhibitors XEN907, TC-N1752 and NaV1.7-IN2, explaining specific binding sites and modulation mechanism for the pore blockers. These inhibitors bind in the central cavity blocking ion permeation, but engage different parts of the cavity wall. XEN907 directly causes α- to π-helix transition of DIV-S6 helix, which tightens the fast inactivation gate. TC-N1752 induces π-helix transition of DII-S6 helix mediated by a conserved asparagine on DIII-S6, which closes the activation gate. NaV1.7-IN2 serves as a pore blocker without causing conformational change. Electrophysiological results demonstrate that XEN907 and TC-N1752 stabilize NaV1.7 in inactivated state and delay the recovery from inactivation. Our results provide structural framework for NaV1.7 modulation by pore blockers, and important implications for developing subtype-selective analgesics.
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12
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Middleton SJ, Perini I, Themistocleous AC, Weir GA, McCann K, Barry AM, Marshall A, Lee M, Mayo LM, Bohic M, Baskozos G, Morrison I, Löken LS, McIntyre S, Nagi SS, Staud R, Sehlstedt I, Johnson RD, Wessberg J, Wood JN, Woods CG, Moqrich A, Olausson H, Bennett DL. Nav1.7 is required for normal C-low threshold mechanoreceptor function in humans and mice. Brain 2022; 145:3637-3653. [PMID: 34957475 PMCID: PMC9586547 DOI: 10.1093/brain/awab482] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 11/03/2021] [Accepted: 11/24/2021] [Indexed: 11/15/2022] Open
Abstract
Patients with bi-allelic loss of function mutations in the voltage-gated sodium channel Nav1.7 present with congenital insensitivity to pain (CIP), whilst low threshold mechanosensation is reportedly normal. Using psychophysics (n = 6 CIP participants and n = 86 healthy controls) and facial electromyography (n = 3 CIP participants and n = 8 healthy controls), we found that these patients also have abnormalities in the encoding of affective touch, which is mediated by the specialized afferents C-low threshold mechanoreceptors (C-LTMRs). In the mouse, we found that C-LTMRs express high levels of Nav1.7. Genetic loss or selective pharmacological inhibition of Nav1.7 in C-LTMRs resulted in a significant reduction in the total sodium current density, an increased mechanical threshold and reduced sensitivity to non-noxious cooling. The behavioural consequence of loss of Nav1.7 in C-LTMRs in mice was an elevation in the von Frey mechanical threshold and less sensitivity to cooling on a thermal gradient. Nav1.7 is therefore not only essential for normal pain perception but also for normal C-LTMR function, cool sensitivity and affective touch.
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Affiliation(s)
- Steven J Middleton
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Irene Perini
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- Center for Medical Image Science and Visualization, Linköping, Sweden
| | - Andreas C Themistocleous
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Greg A Weir
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
- Institute of Neuroscience and Psychology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Kirsty McCann
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Allison M Barry
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Andrew Marshall
- Institute of Aging and Chronic Disease, University of Liverpool, L3 5DA Liverpool, UK
| | - Michael Lee
- University Division of Anaesthesia, University of Cambridge, Cambridge NHS Foundation Trust Hospitals, Hills Road, Cambridge CB2 0QQ, UK
| | - Leah M Mayo
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Manon Bohic
- Aix-Marseille-Université, CNRS, Institute de Biologie du Développement de Marseille, UMR 7288, case 907, 13288 Marseille Cedex 09, France
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Georgios Baskozos
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - India Morrison
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Line S Löken
- Department of Physiology, University of Gothenburg, Gothenburg, Sweden
| | - Sarah McIntyre
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Saad S Nagi
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Roland Staud
- Department of Physiological Sciences, University of Florida College of Veterinary Medicine, Gainesville, FL, USA
| | - Isac Sehlstedt
- Department of Psychology, University of Gothenburg, Gothenburg, Sweden
| | - Richard D Johnson
- Department of Physiology, University of Gothenburg, Gothenburg, Sweden
- Department of Physiological Sciences, University of Florida College of Veterinary Medicine, Gainesville, FL, USA
| | - Johan Wessberg
- Department of Physiology, University of Gothenburg, Gothenburg, Sweden
| | - John N Wood
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Christopher G Woods
- Cambridge Institute for Medical Research, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Aziz Moqrich
- Aix-Marseille-Université, CNRS, Institute de Biologie du Développement de Marseille, UMR 7288, case 907, 13288 Marseille Cedex 09, France
| | - Håkan Olausson
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - David L Bennett
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
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13
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Xue Y, Kremer M, Muniz Moreno MDM, Chidiac C, Lorentz R, Birling MC, Barrot M, Herault Y, Gaveriaux-Ruff C. The Human SCN9AR185H Point Mutation Induces Pain Hypersensitivity and Spontaneous Pain in Mice. Front Mol Neurosci 2022; 15:913990. [PMID: 35769334 PMCID: PMC9234669 DOI: 10.3389/fnmol.2022.913990] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/04/2022] [Indexed: 11/13/2022] Open
Abstract
The voltage-gated sodium channel Nav1.7 is encoded by SCN9A gene and plays a critical role in pain sensitivity. Several SCN9A gain-of-function (GOF) mutations have been found in patients with small fiber neuropathy (SFN) having chronic pain, including the R185H mutation. However, for most of these variants, their involvement in pain phenotype still needs to be experimentally elucidated. In order to delineate the impact of R185H mutation on pain sensitivity, we have established the Scn9aR185H mutant mouse model using the CRISPR/Cas9 technology. The Scn9aR185H mutant mice show no cellular alteration in the dorsal root ganglia (DRG) containing cell bodies of sensory neurons and no alteration of growth or global health state. Heterozygous and homozygous animals of both sexes were investigated for pain sensitivity. The mutant mice were more sensitive than the wild-type mice in the tail flick and hot plate tests, acetone, and von Frey tests for sensitivity to heat, cold, and touch, respectively, although with sexual dimorphic effects. The newly developed bioinformatic pipeline, Gdaphen is based on general linear model (GLM) and random forest (RF) classifiers as well as a multifactor analysis of mixed data and shows the qualitative and quantitative variables contributing the most to the pain phenotype. Using Gdaphen, tail flick, Hargreaves, hot plate, acetone, cold plate, and von Frey tests, sex and genotype were found to be contributing most to the pain phenotype. Importantly, the mutant animals displayed spontaneous pain as assessed in the conditioned place preference (CPP) assay. Altogether, our results indicate that Scn9aR185H mice show a pain phenotype, suggesting that the SCN9AR185H mutation identified in patients with SFN having chronic pain contributes to their symptoms. Therefore, we provide genetic evidence for the fact that this mutation in Nav1.7 channel plays an important role in nociception and in the pain experienced by patients with SFN who have this mutation. These findings should aid in exploring further pain treatments based on the Nav1.7 channel.
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Affiliation(s)
- Yaping Xue
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
| | - Mélanie Kremer
- Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Cellulaires et Intégratives (INCI), Université de Strasbourg, Strasbourg, France
| | - Maria del Mar Muniz Moreno
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
| | - Celeste Chidiac
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
| | - Romain Lorentz
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), CELPHEDIA-PHENOMIN-Institut Clinique de la Souris, (PHENOMIN-ICS), Université de Strasbourg, Illkirch, France
| | - Marie-Christine Birling
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), CELPHEDIA-PHENOMIN-Institut Clinique de la Souris, (PHENOMIN-ICS), Université de Strasbourg, Illkirch, France
| | - Michel Barrot
- Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Cellulaires et Intégratives (INCI), Université de Strasbourg, Strasbourg, France
| | - Yann Herault
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), CELPHEDIA-PHENOMIN-Institut Clinique de la Souris, (PHENOMIN-ICS), Université de Strasbourg, Illkirch, France
- *Correspondence: Yann Herault,
| | - Claire Gaveriaux-Ruff
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS) UMR 7242, Université de Strasbourg, Illkirch, France
- Claire Gaveriaux-Ruff,
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14
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Banerjee J, Dorfman MD, Fasnacht R, Douglass JD, Wyse-Jackson AC, Barria A, Thaler JP. CX3CL1 Action on Microglia Protects from Diet-Induced Obesity by Restoring POMC Neuronal Excitability and Melanocortin System Activity Impaired by High-Fat Diet Feeding. Int J Mol Sci 2022; 23:6380. [PMID: 35742824 PMCID: PMC9224384 DOI: 10.3390/ijms23126380] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 05/31/2022] [Accepted: 06/04/2022] [Indexed: 02/04/2023] Open
Abstract
Both hypothalamic microglial inflammation and melanocortin pathway dysfunction contribute to diet-induced obesity (DIO) pathogenesis. Previous studies involving models of altered microglial signaling demonstrate altered DIO susceptibility with corresponding POMC neuron cytological changes, suggesting a link between microglia and the melanocortin system. We addressed this hypothesis using the specific microglial silencing molecule, CX3CL1 (fractalkine), to determine whether reducing hypothalamic microglial activation can restore POMC/melanocortin signaling to protect against DIO. We performed metabolic analyses in high fat diet (HFD)-fed mice with targeted viral overexpression of CX3CL1 in the hypothalamus. Electrophysiologic recording in hypothalamic slices from POMC-MAPT-GFP mice was used to determine the effects of HFD feeding and microglial silencing via minocycline or CX3CL1 on GFP-labeled POMC neurons. Finally, mice with hypothalamic overexpression of CX3CL1 received central treatment with the melanocortin receptor antagonist SHU9119 to determine whether melanocortin signaling is required for the metabolic benefits of CX3CL1. Hypothalamic overexpression of CX3CL1 increased leptin sensitivity and POMC gene expression, while reducing weight gain in animals fed an HFD. In electrophysiological recordings from hypothalamic slice preparations, HFD feeding was associated with reduced POMC neuron excitability and increased amplitude of inhibitory postsynaptic currents. Microglial silencing using minocycline or CX3CL1 treatment reversed these HFD-induced changes in POMC neuron electrophysiologic properties. Correspondingly, blockade of melanocortin receptor signaling in vivo prevented both the acute and chronic reduction in food intake and body weight mediated by CX3CL1. Our results show that suppressing microglial activation during HFD feeding reduces DIO susceptibility via a mechanism involving increased POMC neuron excitability and melanocortin signaling.
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Affiliation(s)
- Jineta Banerjee
- Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, University of Washington Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA; (J.B.); (M.D.D.); (R.F.); (J.D.D.); (A.C.W.-J.)
| | - Mauricio D. Dorfman
- Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, University of Washington Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA; (J.B.); (M.D.D.); (R.F.); (J.D.D.); (A.C.W.-J.)
| | - Rachael Fasnacht
- Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, University of Washington Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA; (J.B.); (M.D.D.); (R.F.); (J.D.D.); (A.C.W.-J.)
| | - John D. Douglass
- Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, University of Washington Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA; (J.B.); (M.D.D.); (R.F.); (J.D.D.); (A.C.W.-J.)
| | - Alice C. Wyse-Jackson
- Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, University of Washington Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA; (J.B.); (M.D.D.); (R.F.); (J.D.D.); (A.C.W.-J.)
| | - Andres Barria
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98109, USA;
| | - Joshua P. Thaler
- Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, University of Washington Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA; (J.B.); (M.D.D.); (R.F.); (J.D.D.); (A.C.W.-J.)
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15
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Grossman CD, Cohen JY. Neuromodulation and Neurophysiology on the Timescale of Learning and Decision-Making. Annu Rev Neurosci 2022; 45:317-337. [PMID: 35363533 DOI: 10.1146/annurev-neuro-092021-125059] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Nervous systems evolved to effectively navigate the dynamics of the environment to achieve their goals. One framework used to study this fundamental problem arose in the study of learning and decision-making. In this framework, the demands of effective behavior require slow dynamics-on the scale of seconds to minutes-of networks of neurons. Here, we review the phenomena and mechanisms involved. Using vignettes from a few species and areas of the nervous system, we view neuromodulators as key substrates for temporal scaling of neuronal dynamics. Expected final online publication date for the Annual Review of Neuroscience, Volume 45 is July 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Cooper D Grossman
- The Solomon H. Snyder Department of Neuroscience, Brain Science Institute, and Kavli Neuroscience Discovery Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA;
| | - Jeremiah Y Cohen
- The Solomon H. Snyder Department of Neuroscience, Brain Science Institute, and Kavli Neuroscience Discovery Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA;
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16
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Royo M, Escolano BA, Madrigal MP, Jurado S. AMPA Receptor Function in Hypothalamic Synapses. Front Synaptic Neurosci 2022; 14:833449. [PMID: 35173598 PMCID: PMC8842481 DOI: 10.3389/fnsyn.2022.833449] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 01/03/2022] [Indexed: 12/15/2022] Open
Abstract
AMPA receptors (AMPARs) are critical for mediating glutamatergic synaptic transmission and plasticity, thus playing a major role in the molecular machinery underlying cellular substrates of memory and learning. Their expression pattern, transport and regulatory mechanisms have been extensively studied in the hippocampus, but their functional properties in other brain regions remain poorly understood. Interestingly, electrophysiological and molecular evidence has confirmed a prominent role of AMPARs in the regulation of hypothalamic function. This review summarizes the existing evidence on AMPAR-mediated transmission in the hypothalamus, where they are believed to orchestrate the role of glutamatergic transmission in autonomous, neuroendocrine function, body homeostasis, and social behavior.
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17
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Bano-Otalora B, Moye MJ, Brown T, Lucas RJ, Diekman CO, Belle MD. Daily electrical activity in the master circadian clock of a diurnal mammal. eLife 2021; 10:68179. [PMID: 34845984 PMCID: PMC8631794 DOI: 10.7554/elife.68179] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 10/09/2021] [Indexed: 11/13/2022] Open
Abstract
Circadian rhythms in mammals are orchestrated by a central clock within the suprachiasmatic nuclei (SCN). Our understanding of the electrophysiological basis of SCN activity comes overwhelmingly from a small number of nocturnal rodent species, and the extent to which these are retained in day-active animals remains unclear. Here, we recorded the spontaneous and evoked electrical activity of single SCN neurons in the diurnal rodent Rhabdomys pumilio, and developed cutting-edge data assimilation and mathematical modeling approaches to uncover the underlying ionic mechanisms. As in nocturnal rodents, R. pumilio SCN neurons were more excited during daytime hours. By contrast, the evoked activity of R. pumilio neurons included a prominent suppressive response that is not present in the SCN of nocturnal rodents. Our modeling revealed and subsequent experiments confirmed transient subthreshold A-type potassium channels as the primary determinant of this response, and suggest a key role for this ionic mechanism in optimizing SCN function to accommodate R. pumilio's diurnal niche.
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Affiliation(s)
- Beatriz Bano-Otalora
- Centre for Biological Timing, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom.,Division of Neuroscience and Experimental Psychology, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Matthew J Moye
- Department of Mathematical Sciences, New Jersey Institute of Technology, Newark, United States.,Department of Quantitative Pharmacology and Pharmacometrics (QP2), Kenilworth, United States
| | - Timothy Brown
- Centre for Biological Timing, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom.,Division of Diabetes, Endocrinology and Gastroenterology, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Robert J Lucas
- Centre for Biological Timing, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom.,Division of Neuroscience and Experimental Psychology, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Casey O Diekman
- Department of Mathematical Sciences, New Jersey Institute of Technology, Newark, United States.,EPSRC Centre for Predictive Modelling in Healthcare, Living Systems Institute, University of Exeter, Exeter, United Kingdom
| | - Mino Dc Belle
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, University of Exeter, Exeter, United Kingdom
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18
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Francis N, Borniger JC. Cancer as a homeostatic challenge: the role of the hypothalamus. Trends Neurosci 2021; 44:903-914. [PMID: 34561122 PMCID: PMC9901368 DOI: 10.1016/j.tins.2021.08.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 08/16/2021] [Accepted: 08/30/2021] [Indexed: 02/08/2023]
Abstract
The initiation, progression, and metastatic spread of cancer elicits diverse changes in systemic physiology. In this way, cancer represents a novel homeostatic challenge to the host system. Here, we discuss how the hypothalamus, a critical brain region involved in homeostasis senses, integrates and responds to cancer-induced changes in physiology. Through this lens, cancer-associated changes in behavior (e.g., sleep disruption) and physiology (e.g., glucocorticoid dysregulation) can be viewed as the result of an inability to re-establish homeostasis. We provide examples at each level (receptor sensing, integration of systemic signals, and efferent regulatory pathways) of how homeostatic organization becomes disrupted across different cancers. Finally, we lay out predictions of this hypothesis and highlight outstanding questions that aim to guide further work in this area.
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Affiliation(s)
- Nikita Francis
- Cold Spring Harbor Laboratory, One Bungtown Rd., Cold Spring Harbor, NY 11724
| | - Jeremy C Borniger
- Cold Spring Harbor Laboratory, One Bungtown Rd., Cold Spring Harbor, NY 11724,Correspondence:
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19
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Chen Z, Pan S, Yin K, Zhang Y, Yuan X, Wang S, Yang S, Shen Q, Tang Y, Li J, Wang Y, Lu Y, Zhang G. Deficiency of ER Ca 2+ sensor STIM1 in AgRP neurons confers protection against dietary obesity. Cell Rep 2021; 37:109868. [PMID: 34686338 DOI: 10.1016/j.celrep.2021.109868] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 06/14/2021] [Accepted: 09/30/2021] [Indexed: 12/13/2022] Open
Abstract
Store-operated calcium entry (SOCE) is pivotal in maintaining intracellular Ca2+ level and cell function; however, its role in obesity development remains largely unknown. Here, we show that the stromal interaction molecule 1 (Stim1), an endoplasmic reticulum (ER) Ca2+ sensor for SOCE, is critically involved in obesity development. Pharmacological blockade of SOCE in the brain, or disruption of Stim1 in hypothalamic agouti-related peptide (AgRP)-producing neurons (ASKO), significantly ameliorates dietary obesity and its associated metabolic disorders. Conversely, constitutive activation of Stim1 in AgRP neurons leads to an obesity-like phenotype. We show that the blockade of SOCE suppresses general translation in neuronal cells via the 2',5'-oligoadenylate synthetase 3 (Oas3)-RNase L signaling. While Oas3 overexpression in AgRP neurons protects mice against dietary obesity, deactivation of RNase L in these neurons significantly abolishes the effect of ASKO. These findings highlight an important role of Stim1 and SOCE in the development of obesity.
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Affiliation(s)
- Zhuo Chen
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China; Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Susu Pan
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China; Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Kaili Yin
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China; Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yuejin Zhang
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei, China; Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaoman Yuan
- Beijing Key Laboratory of Gene Resource and Molecular Development, Beijing, China; Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, Institute of Cell Biology, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Sihan Wang
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China; Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Shujuan Yang
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China; Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Qing Shen
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China; Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yizhe Tang
- Department of Neurology, Shenzhen Institute of Translational Medicine, The First Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen Second People's Hospital, Shenzhen, Guangdong, China
| | - Juxue Li
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China; Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Youjun Wang
- Beijing Key Laboratory of Gene Resource and Molecular Development, Beijing, China; Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, Institute of Cell Biology, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Yisheng Lu
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei, China; Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
| | - Guo Zhang
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China; Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei, China.
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20
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Uyeda A, Quan L, Kato Y, Muramatsu N, Tanabe S, Sakai K, Ichinohe N, Kawahara Y, Suzuki T, Muramatsu R. Dimethylarginine dimethylaminohydrolase 1 as a novel regulator of oligodendrocyte differentiation in the central nervous system remyelination. Glia 2021; 69:2591-2604. [PMID: 34270117 DOI: 10.1002/glia.24060] [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: 12/17/2020] [Revised: 07/07/2021] [Accepted: 07/08/2021] [Indexed: 11/12/2022]
Abstract
Remyelination is a regenerative process that restores the lost neurological function and partially depends on oligodendrocyte differentiation. Differentiation of oligodendrocytes spontaneously occurs after demyelination, depending on the cell intrinsic mechanisms. By combining a loss-of-function genomic screen with a web-resource-based candidate gene identification approach, we identified that dimethylarginine dimethylaminohydrolase 1 (DDAH1) is a novel regulator of oligodendrocyte differentiation. Silencing DDAH1 in oligodendrocytes prevented the expression of myelin basic protein in mouse oligodendrocyte culture with the change in expression of genes annotated with oligodendrocyte development. DDAH1 inhibition attenuated spontaneous remyelination in a cuprizone-induced demyelinated mouse model. Conversely, increased DDAH1 expression enhanced remyelination capacity in experimental autoimmune encephalomyelitis. These results provide a novel therapeutic option for demyelinating diseases by modulating DDAH1 activity.
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Affiliation(s)
- Akiko Uyeda
- Department of Molecular Pharmacology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Lili Quan
- Department of Molecular Pharmacology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Yuki Kato
- Department of RNA Biology and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Nagaaki Muramatsu
- Department of Molecular Pharmacology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan.,Department of Medical and Life Science, Graduate School of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Shogo Tanabe
- Department of Molecular Pharmacology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Kazuhisa Sakai
- Department of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Noritaka Ichinohe
- Department of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Yukio Kawahara
- Department of RNA Biology and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Tatsunori Suzuki
- Department of Medical and Life Science, Graduate School of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Rieko Muramatsu
- Department of Molecular Pharmacology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
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21
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Stincic TL, Bosch MA, Hunker AC, Juarez B, Connors AM, Zweifel LS, Rønnekleiv OK, Kelly MJ. CRISPR knockdown of Kcnq3 attenuates the M-current and increases excitability of NPY/AgRP neurons to alter energy balance. Mol Metab 2021; 49:101218. [PMID: 33766732 PMCID: PMC8093934 DOI: 10.1016/j.molmet.2021.101218] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/12/2021] [Accepted: 03/18/2021] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE Arcuate nucleus neuropeptide Y/agouti-related peptide (NPY/AgRP) neurons drive ingestive behavior. The M-current, a subthreshold non-inactivating potassium current, plays a critical role in regulating NPY/AgRP neuronal excitability. Fasting decreases while 17β-estradiol increases the M-current by regulating the mRNA expression of Kcnq2, 3, and 5 (Kv7.2, 3, and 5) channel subunits. Incorporating KCNQ3 into heteromeric channels has been considered essential to generate a robust M-current. Therefore, we investigated the behavioral and physiological effects of selective Kcnq3 deletion from NPY/AgRP neurons. METHODS We used a single adeno-associated viral vector containing a recombinase-dependent Staphylococcus aureus Cas9 with a single-guide RNA to selectively delete Kcnq3 in NPY/AgRP neurons. Single-cell quantitative measurements of mRNA expression and whole-cell patch clamp experiments were conducted to validate the selective knockdown. Body weight, food intake, and locomotor activity were measured in male mice to assess disruptions in energy balance. RESULTS The virus reduced the expression of Kcnq3 mRNA without affecting Kcnq2 or Kcnq5. The M-current was attenuated, causing NPY/AgRP neurons to be more depolarized, exhibit a higher input resistance, and require less depolarizing current to fire action potentials, indicative of increased excitability. Although the resulting decrease in the M-current did not overtly alter ingestive behavior, it significantly reduced the locomotor activity as measured by open-field testing. Control mice on a high-fat diet exhibited an enhanced M-current and increased Kcnq2 and Kcnq3 expression, but the M-current remained significantly attenuated in KCNQ3 knockdown animals. CONCLUSIONS The M-current plays a critical role in modulating the intrinsic excitability of NPY/AgRP neurons that is essential for maintaining energy homeostasis.
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Affiliation(s)
- Todd L Stincic
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, 97239, USA.
| | - Martha A Bosch
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Avery C Hunker
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, 98195, USA
| | - Barbara Juarez
- Department of Pharmacology, University of Washington, Seattle, WA, 98195, USA
| | - Ashley M Connors
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Larry S Zweifel
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, 98195, USA; Department of Pharmacology, University of Washington, Seattle, WA, 98195, USA
| | - Oline K Rønnekleiv
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, 97239, USA; Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, 97006, USA
| | - Martin J Kelly
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, 97239, USA; Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, 97006, USA.
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22
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Abstract
The chronification of pain can be attributed to changes in membrane receptors and channels underlying neuronal plasticity and signal transduction largely within nociceptive neurons that initiate and maintain pathological pain states. These proteins are subject to dynamic modification by posttranslational modifications, creating a code that controls protein function in time and space. Phosphorylation is an important posttranslational modification that affects ∼30% of proteins in vivo. Increased phosphorylation of various nociceptive ion channels and of their modulators underlies sensitization of different pain states. Cyclin-dependent kinases are proline-directed serine/threonine kinases that impact various biological and cellular systems. Cyclin-dependent kinase 5 (Cdk5), one member of this kinase family, and its activators p35 and p39 are expressed in spinal nerves, dorsal root ganglia, and the dorsal horn of the spinal cord. In neuropathic pain conditions, expression and/or activity of Cdk5 is increased, implicating Cdk5 in nociception. Experimental evidence suggests that Cdk5 is regulated through its own phosphorylation, through increasing p35's interaction with Cdk5, and through cleavage of p35 into p25. This narrative review discusses the molecular mechanisms of Cdk5-mediated regulation of target proteins involved in neuropathic pain. We focus on Cdk5 substrates that have been linked to nociceptive pathways, including channels (eg, transient receptor potential cation channel and voltage-gated calcium channel), proteins involved in neurotransmitter release (eg, synaptophysin and collapsin response mediator protein 2), and receptors (eg, glutamate, purinergic, and opioid). By altering the phosphoregulatory "set point" of proteins involved in pain signaling, Cdk5 thus appears to be an attractive target for treating neuropathic pain conditions.
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23
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MacDonald DI, Sikandar S, Weiss J, Pyrski M, Luiz AP, Millet Q, Emery EC, Mancini F, Iannetti GD, Alles SRA, Arcangeletti M, Zhao J, Cox JJ, Brownstone RM, Zufall F, Wood JN. A central mechanism of analgesia in mice and humans lacking the sodium channel Na V1.7. Neuron 2021; 109:1497-1512.e6. [PMID: 33823138 PMCID: PMC8110947 DOI: 10.1016/j.neuron.2021.03.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 02/05/2020] [Accepted: 03/08/2021] [Indexed: 11/18/2022]
Abstract
Deletion of SCN9A encoding the voltage-gated sodium channel NaV1.7 in humans leads to profound pain insensitivity and anosmia. Conditional deletion of NaV1.7 in sensory neurons of mice also abolishes pain, suggesting that the locus of analgesia is the nociceptor. Here we demonstrate, using in vivo calcium imaging and extracellular recording, that NaV1.7 knockout mice have essentially normal nociceptor activity. However, synaptic transmission from nociceptor central terminals in the spinal cord is greatly reduced by an opioid-dependent mechanism. Analgesia is also reversed substantially by central but not peripheral application of opioid antagonists. In contrast, the lack of neurotransmitter release from olfactory sensory neurons is opioid independent. Male and female humans with NaV1.7-null mutations show naloxone-reversible analgesia. Thus, inhibition of neurotransmitter release is the principal mechanism of anosmia and analgesia in mouse and human Nav1.7-null mutants.
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Affiliation(s)
- Donald Iain MacDonald
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK.
| | - Shafaq Sikandar
- Centre for Experimental Medicine & Rheumatology, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - Jan Weiss
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Martina Pyrski
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Ana P Luiz
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Queensta Millet
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Edward C Emery
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Flavia Mancini
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
| | - Gian D Iannetti
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK; Neuroscience and Behaviour Laboratory, Istituto Italiano di Tecnologia, Rome, Italy
| | - Sascha R A Alles
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Manuel Arcangeletti
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Jing Zhao
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - James J Cox
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | | | - Frank Zufall
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - John N Wood
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK.
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24
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Goodwin G, McMahon SB. The physiological function of different voltage-gated sodium channels in pain. Nat Rev Neurosci 2021; 22:263-274. [PMID: 33782571 DOI: 10.1038/s41583-021-00444-w] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2021] [Indexed: 02/01/2023]
Abstract
Evidence from human genetic pain disorders shows that voltage-gated sodium channel α-subtypes Nav1.7, Nav1.8 and Nav1.9 are important in the peripheral signalling of pain. Nav1.7 is of particular interest because individuals with Nav1.7 loss-of-function mutations are congenitally insensitive to acute and chronic pain, and there is considerable hope that phenocopying these effects with a pharmacological antagonist will produce a new class of analgesic drug. However, studies in these rare individuals do not reveal how and where voltage-gated sodium channels contribute to pain signalling, which is of critical importance for drug development. More than a decade of research utilizing rodent genetic models and pharmacological tools to study voltage-gated sodium channels in pain has begun to unravel the role of different subtypes. Here, we review the contribution of individual channel subtypes in three key physiological processes necessary for transmission of sensory information to the CNS: transduction of stimuli at peripheral nerve terminals, axonal transmission of action potentials and neurotransmitter release from central terminals. These data suggest that drugs seeking to recapitulate the analgesic effects of loss of function of Nav1.7 will need to be brain-penetrant - which most of those developed to date are not.
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Affiliation(s)
- George Goodwin
- Pain and Neurorestoration Group, King's College London, London, UK.
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25
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Le Cann K, Foerster A, Rösseler C, Erickson A, Hautvast P, Giesselmann S, Pensold D, Kurth I, Rothermel M, Mattis VB, Zimmer-Bensch G, von Hörsten S, Denecke B, Clarner T, Meents J, Lampert A. The difficulty to model Huntington's disease in vitro using striatal medium spiny neurons differentiated from human induced pluripotent stem cells. Sci Rep 2021; 11:6934. [PMID: 33767215 PMCID: PMC7994641 DOI: 10.1038/s41598-021-85656-x] [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: 08/07/2020] [Accepted: 03/03/2021] [Indexed: 12/21/2022] Open
Abstract
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by an expanded polyglutamine repeat in the huntingtin gene. The neuropathology of HD is characterized by the decline of a specific neuronal population within the brain, the striatal medium spiny neurons (MSNs). The origins of this extreme vulnerability remain unknown. Human induced pluripotent stem cell (hiPS cell)-derived MSNs represent a powerful tool to study this genetic disease. However, the differentiation protocols published so far show a high heterogeneity of neuronal populations in vitro. Here, we compared two previously published protocols to obtain hiPS cell-derived striatal neurons from both healthy donors and HD patients. Patch-clamp experiments, immunostaining and RT-qPCR were performed to characterize the neurons in culture. While the neurons were mature enough to fire action potentials, a majority failed to express markers typical for MSNs. Voltage-clamp experiments on voltage-gated sodium (Nav) channels revealed a large variability between the two differentiation protocols. Action potential analysis did not reveal changes induced by the HD mutation. This study attempts to demonstrate the current challenges in reproducing data of previously published differentiation protocols and in generating hiPS cell-derived striatal MSNs to model a genetic neurodegenerative disorder in vitro.
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Affiliation(s)
- Kim Le Cann
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Alec Foerster
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Corinna Rösseler
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Andelain Erickson
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany
| | - Petra Hautvast
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany
| | | | - Daniel Pensold
- Institute of Biology II, Division of Functional Epigenetics in the Animal Model, RWTH Aachen University, 52074, Aachen, Germany
| | - Ingo Kurth
- Intitute of Human Genetic, RWTH Aachen University, 52074, Aachen, Germany
| | - Markus Rothermel
- Institute Für Biology II, Department Chemosensation, AG Neuromodulation, 52074, Aachen, Germany
| | - Virginia B Mattis
- Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
- Fujifilm Cellular Dynamics, Madison, WI, 53711, USA
| | - Geraldine Zimmer-Bensch
- Institute of Biology II, Division of Functional Epigenetics in the Animal Model, RWTH Aachen University, 52074, Aachen, Germany
| | - Stephan von Hörsten
- Intitute of Virology, Clinical and Molecular Virology, Animal Center of Preclinical Experiments (PETZ), 91054, Erlangen, Germany
| | | | - Tim Clarner
- Intitute for Neuroanatomy, MIT 1, 52074, Aachen, Germany
| | - Jannis Meents
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany.
- Multi Channel Systems MCS GmbH, Aspenhaustrasse 21, 72770, Reutlingen, Germany.
| | - Angelika Lampert
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, 52074, Aachen, Germany.
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26
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Alles SRA, Nascimento F, Luján R, Luiz AP, Millet Q, Bangash MA, Santana-Varela S, Zhou X, Cox JJ, Okorokov AL, Beato M, Zhao J, Wood JN. Sensory neuron-derived Na V1.7 contributes to dorsal horn neuron excitability. SCIENCE ADVANCES 2020; 6:eaax4568. [PMID: 32128393 PMCID: PMC7030926 DOI: 10.1126/sciadv.aax4568] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 12/04/2019] [Indexed: 05/08/2023]
Abstract
Expression of the voltage-gated sodium channel NaV1.7 in sensory neurons is required for pain sensation. We examined the role of NaV1.7 in the dorsal horn of the spinal cord using an epitope-tagged NaV1.7 knock-in mouse. Immuno-electron microscopy showed the presence of NaV1.7 in dendrites of superficial dorsal horn neurons, despite the absence of mRNA. Rhizotomy of L5 afferent nerves lowered the levels of NaV1.7 in the dorsal horn. Peripheral nervous system-specific NaV1.7 null mutant mice showed central deficits, with lamina II dorsal horn tonic firing neurons more than halved and single spiking neurons more than doubled. NaV1.7 blocker PF05089771 diminished excitability in dorsal horn neurons but had no effect on NaV1.7 null mutant mice. These data demonstrate an unsuspected functional role of primary afferent neuron-generated NaV1.7 in dorsal horn neurons and an expression pattern that would not be predicted by transcriptomic analysis.
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Affiliation(s)
- Sascha R. A. Alles
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Filipe Nascimento
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Rafael Luján
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Department Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Campus Biosanitario, C/Almansa 14, 02008 Albacete, Spain
| | - Ana P. Luiz
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Queensta Millet
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - M. Ali Bangash
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Sonia Santana-Varela
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Xuelong Zhou
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
- Department of Anesthesiology, The First Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - James J. Cox
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Andrei L. Okorokov
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Marco Beato
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
- Corresponding author. (M.B.); (J.Z.); (J.N.W.)
| | - Jing Zhao
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
- Corresponding author. (M.B.); (J.Z.); (J.N.W.)
| | - John N. Wood
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
- Corresponding author. (M.B.); (J.Z.); (J.N.W.)
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27
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Manion J, Waller MA, Clark T, Massingham JN, Neely GG. Developing Modern Pain Therapies. Front Neurosci 2019; 13:1370. [PMID: 31920521 PMCID: PMC6933609 DOI: 10.3389/fnins.2019.01370] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 12/04/2019] [Indexed: 12/24/2022] Open
Abstract
Chronic pain afflicts as much as 50% of the population at any given time but our methods to address pain remain limited, ineffective and addictive. In order to develop new therapies an understanding of the mechanisms of painful sensitization is essential. We discuss here recent progress in the understanding of mechanisms underlying pain, and how these mechanisms are being targeted to produce modern, specific therapies for pain. Finally, we make recommendations for the next generation of targeted, effective, and safe pain therapies.
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Affiliation(s)
- John Manion
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Matthew A. Waller
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Teleri Clark
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Joshua N. Massingham
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - G. Gregory Neely
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
- Genome Editing Initiative, The University of Sydney, Sydney, NSW, Australia
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28
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Estradiol Enhances the Depolarizing Response to GABA and AMPA Synaptic Conductances in Arcuate Kisspeptin Neurons by Diminishing Voltage-Gated Potassium Currents. J Neurosci 2019; 39:9532-9545. [PMID: 31628184 DOI: 10.1523/jneurosci.0378-19.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 09/24/2019] [Accepted: 10/07/2019] [Indexed: 01/31/2023] Open
Abstract
Synaptic and intrinsic properties interact to sculpt neuronal output. Kisspeptin neurons in the hypothalamic arcuate nucleus help convey homeostatic estradiol feedback to central systems controlling fertility. Estradiol increases membrane depolarization induced by GABAA receptor activation in these neurons. We hypothesized that the mechanisms underlying estradiol-induced alterations in postsynaptic response to GABA, and also AMPA, receptor activation include regulation of voltage-gated potassium currents. Whole-cell recordings of arcuate kisspeptin neurons in brain slices from ovariectomized (OVX) and OVX+estradiol (OVX+E) female mice during estradiol negative feedback revealed that estradiol reduced capacitance, reduced transient and sustained potassium currents, and altered voltage dependence and kinetics of transient currents. Consistent with these observations, estradiol reduced rheobase and action potential latency. To study more directly interactions between synaptic and active intrinsic estradiol feedback targets, dynamic clamp was used to simulate GABA and AMPA conductances. Both GABA and AMPA dynamic clamp-induced postsynaptic potentials (PSPs) were smaller in neurons from OVX than OVX+E mice; blocking transient potassium currents eliminated this difference. To interrogate the role of the estradiol-induced changes in passive intrinsic properties, different Markov model structures based on the properties of the transient potassium current in cells from OVX or OVX+E mice were combined in silico with passive properties reflecting these two endocrine conditions. Some of tested models reproduced the effect on PSPs in silico, revealing that AMPA PSPs were more sensitive to changes in capacitance. These observations support the hypothesis that PSPs in arcuate kisspeptin neurons are regulated by estradiol-sensitive mechanisms including potassium conductances and membrane properties.SIGNIFICANCE STATEMENT Kisspeptin neurons relay estradiol feedback to gonadotropin-releasing hormone neurons, which regulate the reproductive system. The fast synaptic neurotransmitters GABA and glutamate rapidly depolarize arcuate kisspeptin neurons and estradiol increases this depolarization. Estradiol reduced both potassium current in the membrane potential range typically achieved during response to fast synaptic inputs and membrane capacitance. Using simulated GABA and glutamate synaptic inputs, we showed changes in both the passive and active intrinsic properties induced by in vivo estradiol treatment affect the response to synaptic inputs, with capacitance having a greater effect on response to glutamate. The suppression of both passive and active intrinsic properties by estradiol feedback thus renders arcuate kisspeptin neurons more sensitive to fast synaptic inputs.
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Mulcahy JV, Pajouhesh H, Beckley JT, Delwig A, Bois JD, Hunter JC. Challenges and Opportunities for Therapeutics Targeting the Voltage-Gated Sodium Channel Isoform Na V1.7. J Med Chem 2019; 62:8695-8710. [PMID: 31012583 PMCID: PMC6786914 DOI: 10.1021/acs.jmedchem.8b01906] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Voltage-gated sodium ion channel subtype 1.7 (NaV1.7) is a high interest target for the discovery of non-opioid analgesics. Compelling evidence from human genetic data, particularly the finding that persons lacking functional NaV1.7 are insensitive to pain, has spurred considerable effort to develop selective inhibitors of this Na+ ion channel target as analgesic medicines. Recent clinical setbacks and disappointing performance of preclinical compounds in animal pain models, however, have led to skepticism around the potential of selective NaV1.7 inhibitors as human therapeutics. In this Perspective, we discuss the attributes and limitations of recently disclosed investigational drugs targeting NaV1.7 and review evidence that, by better understanding the requirements for selectivity and target engagement, the opportunity to deliver effective analgesic medicines targeting NaV1.7 endures.
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Affiliation(s)
- John V. Mulcahy
- SiteOne Therapeutics, 280 Utah Ave, Suite 250, South San Francisco, CA 94080
| | - Hassan Pajouhesh
- SiteOne Therapeutics, 280 Utah Ave, Suite 250, South San Francisco, CA 94080
| | - Jacob T. Beckley
- SiteOne Therapeutics, 351 Evergreen Drive, Suite B1, Bozeman, MT 59715
| | - Anton Delwig
- SiteOne Therapeutics, 280 Utah Ave, Suite 250, South San Francisco, CA 94080
| | - J. Du Bois
- Stanford University, Lokey Chemistry and Biology, 337 Campus Drive, Stanford, CA 94305
| | - John C. Hunter
- SiteOne Therapeutics, 280 Utah Ave, Suite 250, South San Francisco, CA 94080
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Sinden DS, Holman CD, Bare CJ, Sun X, Gade AR, Cohen DE, Pitt GS. Knockout of the X-linked Fgf13 in the hypothalamic paraventricular nucleus impairs sympathetic output to brown fat and causes obesity. FASEB J 2019; 33:11579-11594. [PMID: 31339804 PMCID: PMC6994920 DOI: 10.1096/fj.201901178r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 07/01/2019] [Indexed: 12/15/2022]
Abstract
Fibroblast growth factor (FGF)13, a nonsecreted, X-linked, FGF homologous factor, is differentially expressed in adipocytes in response to diet, yet Fgf13's role in metabolism has not been explored. Heterozygous Fgf13 knockouts fed normal chow and housed at 22°C showed hyperactivity accompanying reduced core temperature and obesity when housed at 30°C. Those heterozygous knockouts showed defects in thermogenesis even at 30°C and an inability to protect core temperature. Surprisingly, we detected trivial FGF13 in adipose of wild-type mice fed normal chow and no obesity in adipose-specific heterozygous knockouts housed at 30°C, and we detected an intact brown fat response through exogenous β3 agonist stimulation, suggesting a defect in sympathetic drive to brown adipose tissue. In contrast, hypothalamic-specific ablation of Fgf13 recapitulated weight gain at 30°C. Norepinephrine turnover in brown fat was reduced at both housing temperatures. Thus, our data suggest that impaired CNS regulation of sympathetic activation of brown fat underlies obesity and thermogenesis in Fgf13 heterozygous knockouts fed normal chow.-Sinden, D. S., Holman, C. D., Bare, C. J., Sun, X., Gade, A. R., Cohen, D. E., Pitt, G. S. Knockout of the X-linked Fgf13 in the hypothalamic paraventricular nucleus impairs sympathetic output to brown fat and causes obesity.
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Affiliation(s)
- Daniel S. Sinden
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina, USA
- Cardiovascular Research Institute, Weill Cornell Medical College, New York, New York, USA
| | - Corey D. Holman
- Division of Gastroenterology and Hepatology, Weill Cornell Medical College, New York, New York, USA
| | - Curtis J. Bare
- Division of Gastroenterology and Hepatology, Weill Cornell Medical College, New York, New York, USA
| | - Xiaolu Sun
- Cardiovascular Research Institute, Weill Cornell Medical College, New York, New York, USA
| | - Aravind R. Gade
- Cardiovascular Research Institute, Weill Cornell Medical College, New York, New York, USA
| | - David E. Cohen
- Division of Gastroenterology and Hepatology, Weill Cornell Medical College, New York, New York, USA
| | - Geoffrey S. Pitt
- Cardiovascular Research Institute, Weill Cornell Medical College, New York, New York, USA
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Abstract
Acute pain is adaptive, but chronic pain is a global challenge. Many chronic pain syndromes are peripheral in origin and reflect hyperactivity of peripheral pain-signaling neurons. Current treatments are ineffective or only partially effective and in some cases can be addictive, underscoring the need for better therapies. Molecular genetic studies have now linked multiple human pain disorders to voltage-gated sodium channels, including disorders characterized by insensitivity or reduced sensitivity to pain and others characterized by exaggerated pain in response to normally innocuous stimuli. Here, we review recent developments that have enhanced our understanding of pathophysiological mechanisms in human pain and advances in targeting sodium channels in peripheral neurons for the treatment of pain using novel and existing sodium channel blockers.
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Affiliation(s)
- Sulayman D Dib-Hajj
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510, USA; .,Rehabilitation Research Center, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut 06516, USA
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510, USA; .,Rehabilitation Research Center, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut 06516, USA
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GABAergic Inputs to POMC Neurons Originating from the Dorsomedial Hypothalamus Are Regulated by Energy State. J Neurosci 2019; 39:6449-6459. [PMID: 31235650 DOI: 10.1523/jneurosci.3193-18.2019] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 05/21/2019] [Accepted: 06/10/2019] [Indexed: 02/06/2023] Open
Abstract
Neuronal circuits regulating hunger and satiety synthesize information encoding the energy state of the animal and translate those signals into motivated behaviors to meet homeostatic needs. Proopiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus are activated by energy surfeits and inhibited by energy deficits. When activated, these cells inhibit food intake and facilitate weight loss. Conversely, decreased activity in POMC cells is associated with increased food intake and obesity. Circulating nutrients and hormones modulate the activity of POMC neurons over protracted periods of time. However, recent work indicates that calcium activity in POMC cells changes in response to food cues on times scales consistent with the rapid actions of amino acid transmitters. Indeed, the frequency of spontaneous IPSCs (sIPSCs) onto POMC neurons increases during caloric deficits. However, the afferent brain regions responsible for this inhibitory modulation are currently unknown. Here, through the use of brain region-specific deletion of GABA release in both male and female mice we show that neurons in the dorsomedial hypothalamus (DMH) are responsible for the majority of sIPSCs in POMC neurons as well as the fasting-induced increase in sIPSC frequency. Further, the readily releasable pool of GABA vesicles and the release probability of GABA is increased at DMH-to-POMC synapses following an overnight fast. Collectively these data provide evidence that DMH-to-POMC GABA circuitry conveys inhibitory neuromodulation onto POMC cells that is sensitive to the animal's energy state.SIGNIFICANCE STATEMENT Activation of proopiomelanocortin (POMC) cells signals satiety, whereas GABAergic cells in the dorsomedial hypothalamus (DMH) can increase food consumption. However, communication between these cells, particularly in response to changes in metabolic state, is unknown. Here, through targeted inhibition of DMH GABA release, we show that DMH neurons contribute a significant portion of spontaneously released GABA onto POMC cells and are responsible for increased GABAergic inhibition of POMC cells during fasting, likely mediated through increased release probability of GABA at DMH terminals. These data provide important information about inhibitory modulation of metabolic circuitry and provide a mechanism through which POMC neurons could be inhibited, or disinhibited, rapidly in response to food availability.
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Bennett DL, Clark AJ, Huang J, Waxman SG, Dib-Hajj SD. The Role of Voltage-Gated Sodium Channels in Pain Signaling. Physiol Rev 2019; 99:1079-1151. [DOI: 10.1152/physrev.00052.2017] [Citation(s) in RCA: 256] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Acute pain signaling has a key protective role and is highly evolutionarily conserved. Chronic pain, however, is maladaptive, occurring as a consequence of injury and disease, and is associated with sensitization of the somatosensory nervous system. Primary sensory neurons are involved in both of these processes, and the recent advances in understanding sensory transduction and human genetics are the focus of this review. Voltage-gated sodium channels (VGSCs) are important determinants of sensory neuron excitability: they are essential for the initial transduction of sensory stimuli, the electrogenesis of the action potential, and neurotransmitter release from sensory neuron terminals. Nav1.1, Nav1.6, Nav1.7, Nav1.8, and Nav1.9 are all expressed by adult sensory neurons. The biophysical characteristics of these channels, as well as their unique expression patterns within subtypes of sensory neurons, define their functional role in pain signaling. Changes in the expression of VGSCs, as well as posttranslational modifications, contribute to the sensitization of sensory neurons in chronic pain states. Furthermore, gene variants in Nav1.7, Nav1.8, and Nav1.9 have now been linked to human Mendelian pain disorders and more recently to common pain disorders such as small-fiber neuropathy. Chronic pain affects one in five of the general population. Given the poor efficacy of current analgesics, the selective expression of particular VGSCs in sensory neurons makes these attractive targets for drug discovery. The increasing availability of gene sequencing, combined with structural modeling and electrophysiological analysis of gene variants, also provides the opportunity to better target existing therapies in a personalized manner.
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Affiliation(s)
- David L. Bennett
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Alex J. Clark
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Jianying Huang
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Stephen G. Waxman
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Sulayman D. Dib-Hajj
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
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McDermott LA, Weir GA, Themistocleous AC, Segerdahl AR, Blesneac I, Baskozos G, Clark AJ, Millar V, Peck LJ, Ebner D, Tracey I, Serra J, Bennett DL. Defining the Functional Role of Na V1.7 in Human Nociception. Neuron 2019; 101:905-919.e8. [PMID: 30795902 PMCID: PMC6424805 DOI: 10.1016/j.neuron.2019.01.047] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 12/03/2018] [Accepted: 01/18/2019] [Indexed: 12/17/2022]
Abstract
Loss-of-function mutations in NaV1.7 cause congenital insensitivity to pain (CIP); this voltage-gated sodium channel is therefore a key target for analgesic drug development. Utilizing a multi-modal approach, we investigated how NaV1.7 mutations lead to human pain insensitivity. Skin biopsy and microneurography revealed an absence of C-fiber nociceptors in CIP patients, reflected in a reduced cortical response to capsaicin on fMRI. Epitope tagging of endogenous NaV1.7 revealed the channel to be localized at the soma membrane, axon, axon terminals, and the nodes of Ranvier of induced pluripotent stem cell (iPSC) nociceptors. CIP patient-derived iPSC nociceptors exhibited an inability to properly respond to depolarizing stimuli, demonstrating that NaV1.7 is a key regulator of excitability. Using this iPSC nociceptor platform, we found that some NaV1.7 blockers undergoing clinical trials lack specificity. CIP, therefore, arises due to a profound loss of functional nociceptors, which is more pronounced than that reported in rodent models, or likely achievable following acute pharmacological blockade. VIDEO ABSTRACT.
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Affiliation(s)
- Lucy A McDermott
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Greg A Weir
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | | | - Andrew R Segerdahl
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK; Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Iulia Blesneac
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Georgios Baskozos
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Alex J Clark
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Val Millar
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK
| | - Liam J Peck
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Daniel Ebner
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK
| | - Irene Tracey
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK; Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Jordi Serra
- Department of Clinical Neurophysiology, King's College Hospital, London SE5 9RS, UK
| | - David L Bennett
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK.
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Bittar TP, Nair BB, Kim JS, Chandrasekera D, Sherrington A, Iremonger KJ. Corticosterone mediated functional and structural plasticity in corticotropin-releasing hormone neurons. Neuropharmacology 2019; 154:79-86. [PMID: 30771372 DOI: 10.1016/j.neuropharm.2019.02.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 01/22/2019] [Accepted: 02/12/2019] [Indexed: 01/01/2023]
Abstract
Corticosteroid stress hormones drive a multitude of adaptations in the brain. Hypothalamic corticotropin-releasing hormone (CRH) neurons control the circulating levels of corticosteroid stress hormones in the body and are themselves highly sensitive to corticosteroids. CRH neurons have been shown to undergo various adaptions in response to acute stress hormone elevations. However, their structural and physiological changes under chronically elevated corticosterone are less clear. To address this, we determined the structural and functional changes in CRH neurons in the paraventricular nucleus of the hypothalamus following 14 days of corticosterone treatment. We find that prolonged corticosterone elevation reduces CRH neuron intrinsic excitability as measured by summation of subthreshold postsynaptic depolarisations and spiking output. We find that under normal conditions, CRH neurons have a relatively compact and simple dendritic arbor, with a low density of somatic and dendritic spines. Interestingly, the axon originated from a proximal dendrite close to the soma in approximately half of the CRH neurons reconstructed. While prolonged elevation in corticosterone levels did not result in any changes to gross dendritic morphology, it induced a significant reduction in both somatic and dendritic spine density. Together these data reveal the morphological features of hypothalamic CRH neurons and highlight their capacity to undergo functional and morphological plasticity in response to chronic corticosterone elevations. This article is part of the Special Issue entitled 'Hypothalamic Control of Homeostasis'.
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Affiliation(s)
- Thibault P Bittar
- Centre for Neuroendocrinology, Department of Physiology, University of Otago, Dunedin, New Zealand
| | - Betina B Nair
- Centre for Neuroendocrinology, Department of Physiology, University of Otago, Dunedin, New Zealand
| | - Joon S Kim
- Centre for Neuroendocrinology, Department of Physiology, University of Otago, Dunedin, New Zealand
| | - Dhananjie Chandrasekera
- Centre for Neuroendocrinology, Department of Physiology, University of Otago, Dunedin, New Zealand
| | - Aidan Sherrington
- Centre for Neuroendocrinology, Department of Physiology, University of Otago, Dunedin, New Zealand
| | - Karl J Iremonger
- Centre for Neuroendocrinology, Department of Physiology, University of Otago, Dunedin, New Zealand.
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Changes in Both Neuron Intrinsic Properties and Neurotransmission Are Needed to Drive the Increase in GnRH Neuron Firing Rate during Estradiol-Positive Feedback. J Neurosci 2019; 39:2091-2101. [PMID: 30655354 DOI: 10.1523/jneurosci.2880-18.2019] [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: 11/07/2018] [Revised: 12/27/2018] [Accepted: 01/10/2019] [Indexed: 11/21/2022] Open
Abstract
Central output of gonadotropin-releasing hormone (GnRH) neurons controls fertility and is sculpted by sex-steroid feedback. A switch of estradiol action from negative to positive feedback initiates a surge of GnRH release, culminating in ovulation. In ovariectomized mice bearing constant-release estradiol implants (OVX+E), GnRH neuron firing is suppressed in the morning (AM) by negative feedback and activated in the afternoon (PM) by positive feedback; no time-of-day-dependent changes occur in OVX mice. In this daily surge model, GnRH neuron intrinsic properties are shifted to favor increased firing during positive feedback. It is unclear whether this shift and the observed concomitant increase in GABAergic transmission, which typically excites GnRH neurons, are independently sufficient for increasing GnRH neuron firing rate during positive feedback or whether both are needed. To test this, we used dynamic clamp to inject selected previously recorded trains of GABAergic postsynaptic conductances (PSgs) collected during the different feedback states of the daily surge model into GnRH neurons from OVX, OVX+E AM, and OVX+E PM mice. PSg trains mimicking positive feedback initiated more action potentials in cells from OVX+E PM mice than negative feedback or OVX (open feedback loop) trains in all three animal models, but the positive-feedback train was most effective when applied to cells during positive feedback. In silico studies of model GnRH neurons in which >1000 PSg trains were tested exhibited the same results. These observations support the hypothesis that GnRH neurons integrate fast-synaptic and intrinsic changes to increase firing rates during positive feedback.SIGNIFICANCE STATEMENT Infertility affects 15%-20% of couples; failure to ovulate is a common cause. Understanding how the brain controls ovulation is critical for new developments in both infertility treatment and contraception. Ovarian estradiol alters both the intrinsic properties of gonadotropin-releasing hormone (GnRH) neurons and synaptic inputs to these cells coincident with production of sustained GnRH release that ultimately triggers ovulation. We demonstrate here using dynamic clamp and mathematical modeling that estradiol-induced shifts in synaptic transmission alone can increase firing output, but that the intrinsic properties of GnRH neurons during positive feedback further poise these cells for increased response to higher frequency synaptic transmission. These data suggest that GnRH neurons integrate fast-synaptic and intrinsic changes to increase firing rates during the preovulatory GnRH surge.
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Voltage-Dependent Membrane Properties Shape the Size But Not the Frequency Content of Spontaneous Voltage Fluctuations in Layer 2/3 Somatosensory Cortex. J Neurosci 2019; 39:2221-2237. [PMID: 30655351 DOI: 10.1523/jneurosci.1648-18.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 12/30/2018] [Accepted: 01/09/2019] [Indexed: 01/18/2023] Open
Abstract
Under awake and idling conditions, spontaneous intracellular membrane voltage is characterized by large, synchronous, low-frequency fluctuations. Although these properties reflect correlations in synaptic inputs, intrinsic membrane properties often indicate voltage-dependent changes in membrane resistance and time constant values that can amplify and help to generate low-frequency voltage fluctuations. The specific contribution of intrinsic and synaptic factors to the generation of spontaneous fluctuations, however, remains poorly understood. Using visually guided intracellular recordings of somatosensory layer 2/3 pyramidal cells and interneurons in awake male and female mice, we measured the spectrum and size of voltage fluctuation and intrinsic cellular properties at different voltages. In both cell types, depolarizing neurons increased the size of voltage fluctuations. Amplitude changes scaled with voltage-dependent changes in membrane input resistance. Because of the small membrane time constants observed in both pyramidal cells and interneuron cell bodies, the low-frequency content of membrane fluctuations reflects correlations in the synaptic current inputs rather than significant filtering associated with membrane capacitance. Further, blocking synaptic inputs minimally altered somatic membrane resistance and time constant values. Overall, these results indicate that spontaneous synaptic inputs generate a low-conductance state in which the amplitude, but not frequency structure, is influenced by intrinsic membrane properties.SIGNIFICANCE STATEMENT In the absence of sensory drive, cortical activity in awake animals is associated with self-generated and seemingly random membrane voltage fluctuations characterized by large amplitude and low frequency. Partially, these properties reflect correlations in synaptic input. Nonetheless, neurons express voltage-dependent intrinsic properties that can potentially influence the amplitude and frequency of spontaneous activity. Using visually guided intracellular recordings of cortical neurons in awake mice, we measured the voltage dependence of spontaneous voltage fluctuations and intrinsic membrane properties. We show that voltage-dependent changes in membrane resistance amplify synaptic activity, whereas the frequency of voltage fluctuations reflects correlations in synaptic inputs. Last, synaptic activity has a small impact on intrinsic membrane properties in both pyramidal cells and interneurons.
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Abstract
In 2000, with the completion of the human genome project, nine related channels were found to comprise the complete voltage-gated sodium gene family and they were renamed NaV1.1–NaV1.9. This millennial event reflected the extraordinary impact of molecular genetics on our understanding of electrical signalling in the nervous system. In this review, studies of animal electricity from the time of Galvani to the present day are described. The seminal experiments and models of Hodgkin and Huxley coupled with the discovery of the structure of DNA, the genetic code and the application of molecular genetics have resulted in an appreciation of the extraordinary diversity of sodium channels and their surprisingly broad repertoire of functions. In the present era, unsuspected roles for sodium channels in a huge range of pathologies have become apparent.
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Affiliation(s)
- John N Wood
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Federico Iseppon
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London, UK
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Isbell HM, Kilpatrick AM, Lin Z, Mahling R, Shea MA. Backbone resonance assignments of complexes of apo human calmodulin bound to IQ motif peptides of voltage-dependent sodium channels Na V1.1, Na V1.4 and Na V1.7. BIOMOLECULAR NMR ASSIGNMENTS 2018; 12:283-289. [PMID: 29728980 PMCID: PMC6274588 DOI: 10.1007/s12104-018-9824-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 04/29/2018] [Indexed: 06/08/2023]
Abstract
Human voltage-gated sodium (NaV) channels are critical for initiating and propagating action potentials in excitable cells. Nine isoforms have different roles but similar topologies, with a pore-forming α-subunit and auxiliary transmembrane β-subunits. NaV pathologies lead to debilitating conditions including epilepsy, chronic pain, cardiac arrhythmias, and skeletal muscle paralysis. The ubiquitous calcium sensor calmodulin (CaM) binds to an IQ motif in the C-terminal tail of the α-subunit of all NaV isoforms, and contributes to calcium-dependent pore-gating in some channels. Previous structural studies of calcium-free (apo) CaM bound to the IQ motifs of NaV1.2, NaV1.5, and NaV1.6 showed that CaM binding was mediated by the C-domain of CaM (CaMC), while the N-domain (CaMN) made no detectable contacts. To determine whether this domain-specific recognition mechanism is conserved in other NaV isoforms, we used solution NMR spectroscopy to assign the backbone resonances of complexes of apo CaM bound to peptides of IQ motifs of NaV1.1, NaV1.4, and NaV1.7. Analysis of chemical shift differences showed that peptide binding only perturbed resonances in CaMC; resonances of CaMN were identical to free CaM. Thus, CaMC residues contribute to the interface with the IQ motif, while CaMN is available to interact elsewhere on the channel.
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Affiliation(s)
- Holly M Isbell
- Department of Biochemistry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, 52242-1109, USA
| | - Adina M Kilpatrick
- Department of Physics and Astronomy, Drake University, Des Moines, IA, 50311-4516, USA
| | - Zesen Lin
- Department of Biochemistry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, 52242-1109, USA
| | - Ryan Mahling
- Department of Biochemistry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, 52242-1109, USA
| | - Madeline A Shea
- Department of Biochemistry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, 52242-1109, USA.
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Yu W, Kwon J, Sohn J, Lee SH, Kim S, Ho W. mGluR5-dependent modulation of dendritic excitability in CA1 pyramidal neurons mediated by enhancement of persistent Na + currents. J Physiol 2018; 596:4141-4156. [PMID: 29870060 PMCID: PMC6117564 DOI: 10.1113/jp275999] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 05/31/2018] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS High-frequency stimulation (HFS) of the Schaffer collateral pathway activates metabotropic glutamate receptor 5 (mGluR5) signalling in the proximal apical dendrites of CA1 pyramidal neurons. The synaptic activation of mGluR5-mediated calcium signalling causes a significant increase in persistent sodium current (INa,P ) in the dendrites. Increased INa,P by HFS underlies potentiation of synaptic inputs at both the proximal and distal dendrite, leading to an enhanced probability of action potential firing associated with decreased action potential thresholds. Therefore, HFS-induced activation of intracellular mGluR5 serves an important role as an instructive signal for potentiation of upcoming inputs by increasing dendritic excitability. ABSTRACT Dendritic Na+ channels in pyramidal neurons are known to amplify synaptic signals, thereby facilitating action potential (AP) generation. However, the mechanisms that modulate dendritic Na+ channels have remained largely uncharacterized. Here, we report a new form of short-term plasticity in which proximal excitatory synaptic inputs to hippocampal CA1 pyramidal neurons transiently elevate dendritic excitability. High-frequency stimulations (HFS) to the Schaffer collateral (SC) pathway activate mGluR5-dependent Ca2+ signalling in the apical dendrites, which, with calmodulin, upregulates specifically Nav1.6 channel-mediated persistent Na+ currents (INa,P ) in the dendrites. This HFS-induced increase in dendritic INa,P results in transient increases in the amplitude of excitatory postsynaptic potentials induced by both proximal SC and distal perforant path stimulation, leading to the enhanced probability of AP firing associated with decreased AP thresholds. Taken together, our study identifies dendritic INa,P as a novel target for mediating activity-dependent modulation of dendritic integration and neuronal output.
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Affiliation(s)
- Weonjin Yu
- Department of PhysiologySeoul National University College of MedicineSeoul110‐799Republic of Korea
- Biomembrane Plasticity Research CenterSeoul National University College of MedicineSeoul110‐799Republic of Korea
| | - Jaehan Kwon
- Department of PhysiologySeoul National University College of MedicineSeoul110‐799Republic of Korea
- Biomembrane Plasticity Research CenterSeoul National University College of MedicineSeoul110‐799Republic of Korea
| | - Jong‐Woo Sohn
- Department of Biological SciencesKorea Advanced Institute of Science and TechnologyDaejeon305‐701Republic of Korea
| | - Suk Ho Lee
- Department of PhysiologySeoul National University College of MedicineSeoul110‐799Republic of Korea
- Biomembrane Plasticity Research CenterSeoul National University College of MedicineSeoul110‐799Republic of Korea
- Neuroscience Research InstituteSeoul National University College of MedicineSeoul110‐799Republic of Korea
| | - Sooyun Kim
- Department of PhysiologySeoul National University College of MedicineSeoul110‐799Republic of Korea
- Biomembrane Plasticity Research CenterSeoul National University College of MedicineSeoul110‐799Republic of Korea
- Neuroscience Research InstituteSeoul National University College of MedicineSeoul110‐799Republic of Korea
| | - Won‐Kyung Ho
- Department of PhysiologySeoul National University College of MedicineSeoul110‐799Republic of Korea
- Biomembrane Plasticity Research CenterSeoul National University College of MedicineSeoul110‐799Republic of Korea
- Neuroscience Research InstituteSeoul National University College of MedicineSeoul110‐799Republic of Korea
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41
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Pereira V, Millet Q, Aramburu J, Lopez-Rodriguez C, Gaveriaux-Ruff C, Wood JN. Analgesia linked to Nav1.7 loss of function requires µ- and δ-opioid receptors. Wellcome Open Res 2018; 3:101. [PMID: 30271888 PMCID: PMC6134336 DOI: 10.12688/wellcomeopenres.14687.1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2018] [Indexed: 01/08/2023] Open
Abstract
Background: Functional deletion of the Scn9a (sodium voltage-gated channel alpha subunit 9) gene encoding sodium channel Nav1.7 makes humans and mice pain-free. Opioid signalling contributes to this analgesic state. We have used pharmacological and genetic approaches to identify the opioid receptors involved in this form of analgesia. We also examined the regulation of proenkephalin expression by the transcription factor Nfat5 that binds upstream of the Penk gene. Methods: We used specific µ-, δ- and κ-opioid receptor antagonists alone or in combination to examine which opioid receptors were necessary for Nav1.7 loss-associated analgesia in mouse behavioural assays of thermal pain. We also used µ- and δ-opioid receptor null mutant mice alone and in combination in behavioural assays to examine the role of these receptors in Nav1.7 knockouts pain free phenotype. Finally, we examined the levels of Penk mRNA in Nfat5-null mutant mice, as this transcription factor binds to consensus sequences upstream of the Penk gene. Results: The pharmacological block or deletion of both µ- and δ-opioid receptors was required to abolish Nav1.7-null opioid-related analgesia. κ-opioid receptor antagonists were without effect. Enkephalins encoded by the Penk gene are upregulated in Nav1.7 nulls. Deleting Nfat5, a transcription factor with binding motifs upstream of Penk, induces the same level of enkephalin mRNA expression as found in Nav1 .7 nulls, but without consequent analgesia. These data confirm that a combination of events linked to Scn9a gene loss is required for analgesia. Higher levels of endogenous enkephalins, potentiated opioid receptors, diminished electrical excitability and loss of neurotransmitter release together contribute to the analgesic phenotype found in Nav1.7-null mouse and human mutants. Conclusions: These observations help explain the failure of Nav1.7 channel blockers alone to produce analgesia and suggest new routes for analgesic drug development.
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Affiliation(s)
- Vanessa Pereira
- Molecular Nociception Group, WIBR, University College London, Gower Street, WC1E 6BT, UK
| | - Queensta Millet
- Molecular Nociception Group, WIBR, University College London, Gower Street, WC1E 6BT, UK
| | - Jose Aramburu
- Immunology Unit, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Carrer Doctor Aiguader No88, 08003 Barcelona, Spain
| | - Cristina Lopez-Rodriguez
- Immunology Unit, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Carrer Doctor Aiguader No88, 08003 Barcelona, Spain
| | - Claire Gaveriaux-Ruff
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Centre National de la Recherche Scientifique , UMR7104, INSERM U1258, Ecole Supérieure de Biotechnologie de Strasbourg, Ilkirch, Strasbourg, France
| | - John N. Wood
- Molecular Nociception Group, WIBR, University College London, Gower Street, WC1E 6BT, UK
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42
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Hsu CL, Zhao X, Milstein AD, Spruston N. Persistent Sodium Current Mediates the Steep Voltage Dependence of Spatial Coding in Hippocampal Pyramidal Neurons. Neuron 2018; 99:147-162.e8. [PMID: 29909995 DOI: 10.1016/j.neuron.2018.05.025] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 04/13/2018] [Accepted: 05/14/2018] [Indexed: 01/19/2023]
Abstract
The mammalian hippocampus forms a cognitive map using neurons that fire according to an animal's position ("place cells") and many other behavioral and cognitive variables. The responses of these neurons are shaped by their presynaptic inputs and the nature of their postsynaptic integration. In CA1 pyramidal neurons, spatial responses in vivo exhibit a strikingly supralinear dependence on baseline membrane potential. The biophysical mechanisms underlying this nonlinear cellular computation are unknown. Here, through a combination of in vitro, in vivo, and in silico approaches, we show that persistent sodium current mediates the strong membrane potential dependence of place cell activity. This current operates at membrane potentials below the action potential threshold and over seconds-long timescales, mediating a powerful and rapidly reversible amplification of synaptic responses, which drives place cell firing. Thus, we identify a biophysical mechanism that shapes the coding properties of neurons composing the hippocampal cognitive map.
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Affiliation(s)
- Ching-Lung Hsu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Xinyu Zhao
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Aaron D Milstein
- Neurosurgery Department, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nelson Spruston
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.
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Erickson A, Deiteren A, Harrington AM, Garcia‐Caraballo S, Castro J, Caldwell A, Grundy L, Brierley SM. Voltage-gated sodium channels: (Na V )igating the field to determine their contribution to visceral nociception. J Physiol 2018; 596:785-807. [PMID: 29318638 PMCID: PMC5830430 DOI: 10.1113/jp273461] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 01/02/2018] [Indexed: 12/19/2022] Open
Abstract
Chronic visceral pain, altered motility and bladder dysfunction are common, yet poorly managed symptoms of functional and inflammatory disorders of the gastrointestinal and urinary tracts. Recently, numerous human channelopathies of the voltage-gated sodium (NaV ) channel family have been identified, which induce either painful neuropathies, an insensitivity to pain, or alterations in smooth muscle function. The identification of these disorders, in addition to the recent utilisation of genetically modified NaV mice and specific NaV channel modulators, has shed new light on how NaV channels contribute to the function of neuronal and non-neuronal tissues within the gastrointestinal tract and bladder. Here we review the current pre-clinical and clinical evidence to reveal how the nine NaV channel family members (NaV 1.1-NaV 1.9) contribute to abdominal visceral function in normal and disease states.
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Affiliation(s)
- Andelain Erickson
- Visceral Pain Research Group, Human Physiology, Centre for Neuroscience, College of Medicine and Public HealthFlinders UniversityBedford ParkSouth Australia5042Australia
- Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of AdelaideSouth Australian Health and Medical Research Institute (SAHMRI)North TerraceAdelaideSouth Australia 5000Australia
| | - Annemie Deiteren
- Visceral Pain Research Group, Human Physiology, Centre for Neuroscience, College of Medicine and Public HealthFlinders UniversityBedford ParkSouth Australia5042Australia
- Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of AdelaideSouth Australian Health and Medical Research Institute (SAHMRI)North TerraceAdelaideSouth Australia 5000Australia
| | - Andrea M. Harrington
- Visceral Pain Research Group, Human Physiology, Centre for Neuroscience, College of Medicine and Public HealthFlinders UniversityBedford ParkSouth Australia5042Australia
- Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of AdelaideSouth Australian Health and Medical Research Institute (SAHMRI)North TerraceAdelaideSouth Australia 5000Australia
| | - Sonia Garcia‐Caraballo
- Visceral Pain Research Group, Human Physiology, Centre for Neuroscience, College of Medicine and Public HealthFlinders UniversityBedford ParkSouth Australia5042Australia
- Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of AdelaideSouth Australian Health and Medical Research Institute (SAHMRI)North TerraceAdelaideSouth Australia 5000Australia
| | - Joel Castro
- Visceral Pain Research Group, Human Physiology, Centre for Neuroscience, College of Medicine and Public HealthFlinders UniversityBedford ParkSouth Australia5042Australia
- Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of AdelaideSouth Australian Health and Medical Research Institute (SAHMRI)North TerraceAdelaideSouth Australia 5000Australia
| | - Ashlee Caldwell
- Visceral Pain Research Group, Human Physiology, Centre for Neuroscience, College of Medicine and Public HealthFlinders UniversityBedford ParkSouth Australia5042Australia
- Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of AdelaideSouth Australian Health and Medical Research Institute (SAHMRI)North TerraceAdelaideSouth Australia 5000Australia
| | - Luke Grundy
- Visceral Pain Research Group, Human Physiology, Centre for Neuroscience, College of Medicine and Public HealthFlinders UniversityBedford ParkSouth Australia5042Australia
- Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of AdelaideSouth Australian Health and Medical Research Institute (SAHMRI)North TerraceAdelaideSouth Australia 5000Australia
| | - Stuart M. Brierley
- Visceral Pain Research Group, Human Physiology, Centre for Neuroscience, College of Medicine and Public HealthFlinders UniversityBedford ParkSouth Australia5042Australia
- Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of AdelaideSouth Australian Health and Medical Research Institute (SAHMRI)North TerraceAdelaideSouth Australia 5000Australia
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44
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Abstract
Hypertension is a prevalent and major health problem, involving a complex integration of different organ systems, including the central nervous system (CNS). The CNS and the hypothalamus in particular are intricately involved in the pathogenesis of hypertension. In fact, evidence supports altered hypothalamic neuronal activity as a major factor contributing to increased sympathetic drive and increased blood pressure. Several mechanisms have been proposed to contribute to hypothalamic-driven sympathetic activity, including altered ion channel function. Ion channels are critical regulators of neuronal excitability and synaptic function in the brain and, thus, important for blood pressure homeostasis regulation. These include sodium channels, voltage-gated calcium channels, and potassium channels being some of them already identified in hypothalamic neurons. This brief review summarizes the hypothalamic ion channels that may be involved in hypertension, highlighting recent findings that suggest that hypothalamic ion channel modulation can affect the central control of blood pressure and, therefore, suggesting future development of interventional strategies designed to treat hypertension.
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Affiliation(s)
- Vera Geraldes
- Instituto de Fisiologia, Universidade de Lisboa, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisbon, Portugal
| | - Sérgio Laranjo
- Instituto de Fisiologia, Universidade de Lisboa, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisbon, Portugal
| | - Isabel Rocha
- Instituto de Fisiologia, Universidade de Lisboa, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisbon, Portugal. .,Centro Cardiovascular da Universidade de Lisboa, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028, Lisbon, Portugal.
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45
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Mutual inhibition of lateral inhibition: a network motif for an elementary computation in the brain. Curr Opin Neurobiol 2018; 49:69-74. [PMID: 29353136 DOI: 10.1016/j.conb.2017.12.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 12/24/2017] [Accepted: 12/30/2017] [Indexed: 02/06/2023]
Abstract
A series of classical studies in non-human primates has revealed the neuronal activity patterns underlying decision-making. However, the circuit mechanisms for such patterns remain largely unknown. Recent detailed circuit analyses in simpler neural systems have started to reveal the connectivity patterns underlying analogous processes. Here we review a few of these systems that share a particular connectivity pattern, namely mutual inhibition of lateral inhibition. Close examination of these systems suggests that this recurring connectivity pattern ('network motif') is a building block to enforce particular dynamics, which can be used not only for simple behavioral choice but also for more complex choices and other brain functions. Thus, a network motif provides an elementary computation that is not specific to a particular brain function and serves as an elementary building block in the brain.
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46
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Rubinstein M, Patowary A, Stanaway IB, McCord E, Nesbitt RR, Archer M, Scheuer T, Nickerson D, Raskind WH, Wijsman EM, Bernier R, Catterall WA, Brkanac Z. Association of rare missense variants in the second intracellular loop of Na V1.7 sodium channels with familial autism. Mol Psychiatry 2018; 23:231-239. [PMID: 27956748 PMCID: PMC5468514 DOI: 10.1038/mp.2016.222] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 10/07/2016] [Accepted: 10/17/2016] [Indexed: 01/21/2023]
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder often accompanied by intellectual disability, language impairment and medical co-morbidities. The heritability of autism is high and multiple genes have been implicated as causal. However, most of these genes have been identified in de novo cases. To further the understanding of familial autism, we performed whole-exome sequencing on five families in which second- and third-degree relatives were affected. By focusing on novel and protein-altering variants, we identified a small set of candidate genes. Among these, a novel private missense C1143F variant in the second intracellular loop of the voltage-gated sodium channel NaV1.7, encoded by the SCN9A gene, was identified in one family. Through electrophysiological analysis, we show that NaV1.7C1143F exhibits partial loss-of-function effects, resulting in slower recovery from inactivation and decreased excitability in cultured cortical neurons. Furthermore, for the same intracellular loop of NaV1.7, we found an excess of rare variants in a case-control variant-burden study. Functional analysis of one of these variants, M932L/V991L, also demonstrated reduced firing in cortical neurons. However, although this variant is rare in Caucasians, it is frequent in Latino population, suggesting that genetic background can alter its effects on phenotype. Although the involvement of the SCN1A and SCN2A genes encoding NaV1.1 and NaV1.2 channels in de novo ASD has previously been demonstrated, our study indicates the involvement of inherited SCN9A variants and partial loss-of-function of NaV1.7 channels in the etiology of rare familial ASD.
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Affiliation(s)
- M Rubinstein
- Department of Pharmacology, University of Washington, Seattle, WA, USA
| | - A Patowary
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - I B Stanaway
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - E McCord
- Department of Pharmacology, University of Washington, Seattle, WA, USA
| | - R R Nesbitt
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - M Archer
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - T Scheuer
- Department of Pharmacology, University of Washington, Seattle, WA, USA
| | - D Nickerson
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - W H Raskind
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA,Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA, USA
| | - E M Wijsman
- Department of Genome Sciences, University of Washington, Seattle, WA, USA,Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA, USA,Department of Biostatistics, University of Washington, Seattle, WA, USA
| | - R Bernier
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - W A Catterall
- Department of Pharmacology, University of Washington, Seattle, WA, USA,Department of Pharmacology, University of Washington, Seattle, WA 98195, USA E-mail:
| | - Z Brkanac
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA,Department of Psychiatry and Behavioral Science, University of Washington, 1959N.E. Pacific Street, Room BB1526, Seattle, WA 98195-6560, USA. E-mail:
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47
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Kanellopoulos AH, Koenig J, Huang H, Pyrski M, Millet Q, Lolignier S, Morohashi T, Gossage SJ, Jay M, Linley JE, Baskozos G, Kessler BM, Cox JJ, Dolphin AC, Zufall F, Wood JN, Zhao J. Mapping protein interactions of sodium channel Na V1.7 using epitope-tagged gene-targeted mice. EMBO J 2018; 37:427-445. [PMID: 29335280 PMCID: PMC5793798 DOI: 10.15252/embj.201796692] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 11/30/2017] [Accepted: 12/05/2017] [Indexed: 11/24/2022] Open
Abstract
The voltage-gated sodium channel NaV1.7 plays a critical role in pain pathways. We generated an epitope-tagged NaV1.7 mouse that showed normal pain behaviours to identify channel-interacting proteins. Analysis of NaV1.7 complexes affinity-purified under native conditions by mass spectrometry revealed 267 proteins associated with Nav1.7 in vivo The sodium channel β3 (Scn3b), rather than the β1 subunit, complexes with Nav1.7, and we demonstrate an interaction between collapsing-response mediator protein (Crmp2) and Nav1.7, through which the analgesic drug lacosamide regulates Nav1.7 current density. Novel NaV1.7 protein interactors including membrane-trafficking protein synaptotagmin-2 (Syt2), L-type amino acid transporter 1 (Lat1) and transmembrane P24-trafficking protein 10 (Tmed10) together with Scn3b and Crmp2 were validated by co-immunoprecipitation (Co-IP) from sensory neuron extract. Nav1.7, known to regulate opioid receptor efficacy, interacts with the G protein-regulated inducer of neurite outgrowth (Gprin1), an opioid receptor-binding protein, demonstrating a physical and functional link between Nav1.7 and opioid signalling. Further information on physiological interactions provided with this normal epitope-tagged mouse should provide useful insights into the many functions now associated with the NaV1.7 channel.
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Affiliation(s)
| | - Jennifer Koenig
- Molecular Nociception Group, WIBR, University College London, London, UK
| | - Honglei Huang
- TDI Mass Spectrometry Laboratory, Target Discovery Institute, University of Oxford, Oxford, UK
| | - Martina Pyrski
- Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany
| | - Queensta Millet
- Molecular Nociception Group, WIBR, University College London, London, UK
| | - Stéphane Lolignier
- Molecular Nociception Group, WIBR, University College London, London, UK
- Université Clermont Auvergne, Inserm U1107 Neuro-Dol, Pharmacologie Fondamentale et Clinique de la Douleur, Clermont-Ferrand, France
| | - Toru Morohashi
- Molecular Nociception Group, WIBR, University College London, London, UK
| | - Samuel J Gossage
- Molecular Nociception Group, WIBR, University College London, London, UK
| | - Maude Jay
- Molecular Nociception Group, WIBR, University College London, London, UK
| | - John E Linley
- Molecular Nociception Group, WIBR, University College London, London, UK
- Neuroscience, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | | | - Benedikt M Kessler
- TDI Mass Spectrometry Laboratory, Target Discovery Institute, University of Oxford, Oxford, UK
| | - James J Cox
- Molecular Nociception Group, WIBR, University College London, London, UK
| | - Annette C Dolphin
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK
| | - Frank Zufall
- Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany
| | - John N Wood
- Molecular Nociception Group, WIBR, University College London, London, UK
| | - Jing Zhao
- Molecular Nociception Group, WIBR, University College London, London, UK
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48
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Ceballos CC, Pena RFO, Roque AC, Leão RM. Non-Decaying postsynaptics potentials and delayed spikes in hippocampal pyramidal neurons generated by a zero slope conductance created by the persistent Na + current. Channels (Austin) 2018; 12:81-88. [PMID: 29380651 PMCID: PMC5972798 DOI: 10.1080/19336950.2018.1433940] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The negative slope conductance created by the persistent sodium current (INaP) prolongs the decay phase of excitatory postsynaptic potentials (EPSPs). In a recent study, we demonstrated that this effect was due to an increase of the membrane time constant. When the negative slope conductance opposes completely the positive slope conductances of the other currents it creates a zero slope conductance region. In this region the membrane time constant is infinite and the decay phase of the EPSPs is virtually absent. Here we show that non-decaying EPSPs are present in CA1 hippocampal pyramidal cells in the zero slope conductance region, in the suprathreshold range of membrane potential. Na+ channel block with tetrodotoxin abolishes the non-decaying EPSPs. Interestingly, the non-decaying EPSPs are observed only in response to artificial excitatory postsynaptic currents (aEPSCs) of small amplitude, and not in response to aEPSCs of big amplitude. We also observed concomitantly delayed spikes with long latencies and high variability only in response to small amplitude aEPSCs. Our results showed that in CA1 pyramidal neurons INaP creates non-decaying EPSPs and delayed spikes in the subthreshold range of membrane potentials, which could potentiate synaptic integration of synaptic potentials coming from distal regions of the dendritic tree.
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Affiliation(s)
- Cesar C Ceballos
- a Department of Physiology , School of Medicine of Ribeirão Preto, University of São Paulo , Ribeirão Preto , SP , Brazil.,b Department of Physics , School of Philosophy, Sciences and Letters, University of São Paulo , Ribeirão Preto , SP , Brazil
| | - Rodrigo F O Pena
- b Department of Physics , School of Philosophy, Sciences and Letters, University of São Paulo , Ribeirão Preto , SP , Brazil
| | - Antônio C Roque
- b Department of Physics , School of Philosophy, Sciences and Letters, University of São Paulo , Ribeirão Preto , SP , Brazil
| | - Ricardo M Leão
- a Department of Physiology , School of Medicine of Ribeirão Preto, University of São Paulo , Ribeirão Preto , SP , Brazil
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49
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Heisler LK, Lam DD. An appetite for life: brain regulation of hunger and satiety. Curr Opin Pharmacol 2017; 37:100-106. [PMID: 29107871 DOI: 10.1016/j.coph.2017.09.002] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 09/11/2017] [Indexed: 02/02/2023]
Abstract
Obesity results from the consumption of food in excess of bodily energy requirements, with the excess energy stored as adipose tissue. Sequelae of obesity, such as heart disease and type 2 diabetes, consistently rank among the top causes of death worldwide. The global prevalence of obesity highlights the urgency of understanding the mechanisms regulating hunger and satiety. Appetite, defined as the motivational drive to obtain food, is regulated by a complex neurocircuitry which integrates a variety of interoceptive signals to gauge nutritional state and guide appropriate levels of food-seeking. Here we review key recent developments in the identification of cell groups, neural circuits, endogenous and exogenous substances, and intracellular signaling pathways which drive hunger and satiety. We also consider particularly promising pharmacological targets for appetite modulation.
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Affiliation(s)
- Lora K Heisler
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen AB25 2ZD, UK.
| | - Daniel D Lam
- Neurologische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, 81675 Munich, Germany; Institut für Neurogenomik, Helmholtz Zentrum München, 85764 Munich, Germany
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50
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He Y, Shu G, Yang Y, Xu P, Xia Y, Wang C, Saito K, Hinton A, Yan X, Liu C, Wu Q, Tong Q, Xu Y. A Small Potassium Current in AgRP/NPY Neurons Regulates Feeding Behavior and Energy Metabolism. Cell Rep 2017; 17:1807-1818. [PMID: 27829152 PMCID: PMC6248907 DOI: 10.1016/j.celrep.2016.10.044] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Revised: 09/21/2016] [Accepted: 10/13/2016] [Indexed: 01/06/2023] Open
Abstract
Neurons that co-express agouti-related peptide (AgRP) and neuropeptide Y (NPY) are indispensable for normal feeding behavior. Firing activities of AgRP/NPY neurons are dynamically regulated by energy status and coordinate appropriate feeding behavior to meet nutritional demands. However, intrinsic mechanisms that regulate AgRP/NPY neural activities during the fed-to-fasted transition are not fully understood. We found that AgRP/NPY neurons in satiated mice express high levels of the small-conductance calcium-activated potassium channel 3 (SK3) and are inhibited by SK3-mediated potassium currents; on the other hand, food deprivation suppresses SK3 expression in AgRP/NPY neurons, and the decreased SK3-mediated currents contribute to fasting-induced activation of these neurons. Genetic mutation of SK3 specifically in AgRP/NPY neurons leads to increased sensitivity to diet-induced obesity, associated with chronic hyperphagia and decreased energy expenditure. Our results identify SK3 as a key intrinsic mediator that coordinates nutritional status with AgRP/NPY neural activities and animals’ feeding behavior and energy metabolism. Firing activities of AgRP/NPY neurons are essential for energy homeostasis. Heet al. demonstrate that SK3-mediated currents inhibit AgRP/NPY neurons in satiated mice and decreased SK3 expression contributes to fasting-induced activation of these neurons. Thus, dynamic SK3 functions coordinate nutritional status with AgRP/NPY neural activities and animals’ energy balance.
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Affiliation(s)
- Yanlin He
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Gang Shu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; College of Animal Science, South China Agricultural University, Guangzhou 100044, China
| | - Yongjie Yang
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Pingwen Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Yan Xia
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Chunmei Wang
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Kenji Saito
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Antentor Hinton
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Xiaofeng Yan
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Chen Liu
- Division of Hypothalamic Research, Department of Internal Medical, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Qi Wu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Yong Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
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