1
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Hough RA, McClellan AD. Spinal cord injury significantly alters the properties of reticulospinal neurons: delayed repolarization mediated by potassium channels. J Neurophysiol 2023; 130:1265-1281. [PMID: 37820016 PMCID: PMC10994645 DOI: 10.1152/jn.00251.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 09/21/2023] [Accepted: 10/10/2023] [Indexed: 10/13/2023] Open
Abstract
After rostral spinal cord injury (SCI) of lampreys, the descending axons of injured (axotomized) reticulospinal (RS) neurons regenerate and locomotor function gradually recovers. Our previous studies indicated that relative to uninjured lamprey RS neurons, injured RS neurons display several dramatic changes in their biophysical properties, called the "injury phenotype." In the present study, at the onset of applied depolarizing current pulses for membrane potentials below as well as above threshold for action potentials (APs), injured RS neurons displayed a transient depolarization consisting of an initial depolarizing component followed by a delayed repolarizing component. In contrast, for uninjured neurons the transient depolarization was mostly only evident at suprathreshold voltages when APs were blocked. For injured RS neurons, the delayed repolarizing component resisted depolarization to threshold and made these neurons less excitable than uninjured RS neurons. After block of voltage-gated sodium and calcium channels for injured RS neurons, the transient depolarization was still present. After a further block of voltage-gated potassium channels, the delayed repolarizing component was abolished or significantly reduced, with little or no effect on the initial depolarizing component. Voltage-clamp experiments indicated that the delayed repolarizing component was due to a noninactivating outward-rectifying potassium channel whose conductance (gK) was significantly larger for injured RS neurons compared to that for uninjured neurons. Thus, SCI results in an increase in gK and other changes in the biophysical properties of injured lamprey RS neurons that lead to a reduction in excitability, which is proposed to create an intracellular environment that supports axonal regeneration.NEW & NOTEWORTHY After spinal cord injury (SCI), lamprey reticulospinal (RS) neurons responded to subthreshold depolarizing current pulses with a transient depolarization, which included an initial depolarization that was due to passive channels followed by a delayed repolarization that was mediated by voltage-gated potassium channels. The conductance of these channels (gK) was significantly increased for RS neurons after SCI and contributed to a reduction in excitability, which is expected to provide supportive conditions for subsequent axonal regeneration.
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Affiliation(s)
- Ryan A Hough
- Division of Biological Sciences, University of Missouri, Columbia, Missouri, United States
| | - Andrew D McClellan
- Division of Biological Sciences, University of Missouri, Columbia, Missouri, United States
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, Missouri, United States
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2
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Gonda S, Köhler I, Haase A, Czubay K, Räk A, Riedel C, Wahle P. Optogenetic stimulation shapes dendritic trees of infragranular cortical pyramidal cells. Front Cell Neurosci 2023; 17:1212483. [PMID: 37587917 PMCID: PMC10427221 DOI: 10.3389/fncel.2023.1212483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 06/09/2023] [Indexed: 08/18/2023] Open
Abstract
Spontaneous or experimentally evoked activity can lead to changes in length and/or branching of neocortical pyramidal cell dendrites. For instance, an early postnatal overexpression of certain AMPA or kainate glutamate receptor subunits leads to larger amplitudes of depolarizing events driven by spontaneous activity, and this increases apical dendritic complexity. Whether stimulation frequency has a role is less clear. In this study, we report that the expression of channelrhodopsin2-eYFP was followed by a 5-day optogenetic stimulation from DIV 5-10 or 11-15 in organotypic cultures of rat visual cortex-evoked dendritic remodeling. Stimulation at 0.05 Hz, at a frequency range of spontaneous calcium oscillations known to occur in the early postnatal neocortex in vivo until eye opening, had no effect. Stimulation with 0.5 Hz, a frequency at which the cortex in vivo adopts after eye opening, unexpectedly caused shorter and somewhat less branched apical dendrites of infragranular pyramidal neurons. The outcome resembles the remodeling of corticothalamic and callosal projection neurons of layers VI and V, which in the adult have apical dendrites no longer terminating in layer I. Exposure to 2.5 Hz, a frequency not occurring naturally during the time windows, evoked dendritic damage. The results suggested that optogenetic stimulation at a biologically meaningful frequency for the selected developmental stage can influence dendrite growth, but contrary to expectation, the optogenetic stimulation decreased dendritic growth.
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3
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Tejero R, Alsakkal M, Hennlein L, Lopez-Cabello AM, Jablonka S, Tabares L. Nifedipine Ameliorates Cellular Differentiation Defects of Smn-Deficient Motor Neurons and Enhances Neuromuscular Transmission in SMA Mice. Int J Mol Sci 2023; 24:ijms24087648. [PMID: 37108811 PMCID: PMC10146780 DOI: 10.3390/ijms24087648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/11/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
In spinal muscular atrophy (SMA), mutations in or loss of the Survival Motor Neuron 1 (SMN1) gene reduce full-length SMN protein levels, which leads to the degeneration of a percentage of motor neurons. In mouse models of SMA, the development and maintenance of spinal motor neurons and the neuromuscular junction (NMJ) function are altered. Since nifedipine is known to be neuroprotective and increases neurotransmission in nerve terminals, we investigated its effects on cultured spinal cord motor neurons and motor nerve terminals of control and SMA mice. We found that application of nifedipine increased the frequency of spontaneous Ca2+ transients, growth cone size, cluster-like formations of Cav2.2 channels, and it normalized axon extension in SMA neurons in culture. At the NMJ, nifedipine significantly increased evoked and spontaneous release at low-frequency stimulation in both genotypes. High-strength stimulation revealed that nifedipine increased the size of the readily releasable pool (RRP) of vesicles in control but not SMA mice. These findings provide experimental evidence about the ability of nifedipine to prevent the appearance of developmental defects in SMA embryonic motor neurons in culture and reveal to which extent nifedipine could still increase neurotransmission at the NMJ in SMA mice under different functional demands.
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Affiliation(s)
- Rocio Tejero
- Department of Medical Physiology and Biophysics, School of Medicine, University of Seville, 41009 Seville, Spain
| | - Mohammad Alsakkal
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Luisa Hennlein
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Ana M Lopez-Cabello
- Department of Medical Physiology and Biophysics, School of Medicine, University of Seville, 41009 Seville, Spain
| | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Lucia Tabares
- Department of Medical Physiology and Biophysics, School of Medicine, University of Seville, 41009 Seville, Spain
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4
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Nakai-Shimoda H, Himeno T, Okawa T, Miura-Yura E, Sasajima S, Kato M, Yamada Y, Morishita Y, Tsunekawa S, Kato Y, Seino Y, Inoue R, Kondo M, Seino S, Naruse K, Kato K, Mizukami H, Nakamura J, Kamiya H. Kir6.2-deficient mice develop somatosensory dysfunction and axonal loss in the peripheral nerves. iScience 2022; 25:103609. [PMID: 35005553 PMCID: PMC8719014 DOI: 10.1016/j.isci.2021.103609] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 11/27/2021] [Accepted: 12/08/2021] [Indexed: 10/26/2022] Open
Abstract
Glucose-responsive ATP-sensitive potassium channels (KATP) are expressed in a variety of tissues including nervous systems. The depolarization of the membrane potential induced by glucose may lead to hyperexcitability of neurons and induce excitotoxicity. However, the roles of KATP in the peripheral nervous system (PNS) are poorly understood. Here, we determine the roles of KATP in the PNS using KATP-deficient (Kir6.2-deficient) mice. We demonstrate that neurite outgrowth of dorsal root ganglion (DRG) neurons was reduced by channel closers sulfonylureas. However, a channel opener diazoxide elongated the neurite. KATP subunits were expressed in mouse DRG, and expression of certain subunits including Kir6.2 was increased in diabetic mice. In Kir6.2-deficient mice, the current perception threshold, thermal perception threshold, and sensory nerve conduction velocity were impaired. Electron microscopy revealed a reduction of unmyelinated and small myelinated fibers in the sural nerves. In conclusion, KATP may contribute to the development of peripheral neuropathy.
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Affiliation(s)
- Hiromi Nakai-Shimoda
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Tatsuhito Himeno
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan.,Department of Innovative Diabetes Therapy, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Tetsuji Okawa
- Department of Endocrinology, Gifu Prefectural Tajimi Hospital, Tajimi 507-8522, Japan
| | - Emiri Miura-Yura
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Sachiko Sasajima
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Makoto Kato
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Yuichiro Yamada
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Yoshiaki Morishita
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Shin Tsunekawa
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Yoshiro Kato
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Yusuke Seino
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Fujita Health University School of Medicine, Toyoake 470-1192, Aichi, Japan
| | - Rieko Inoue
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Masaki Kondo
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Susumu Seino
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe 650-0047, Japan
| | - Keiko Naruse
- Department of Internal Medicine, Aichi Gakuin University School of Dentistry, Nagoya 464-0821, Japan
| | - Koichi Kato
- Department of Medicine, Aichi Gakuin University School of Pharmacy, Nagoya 464-8650, Japan
| | - Hiroki Mizukami
- Department of Pathology and Molecular Medicine, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
| | - Jiro Nakamura
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan.,Department of Innovative Diabetes Therapy, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
| | - Hideki Kamiya
- Division of Diabetes, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute 480-1185, Japan
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5
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Cheng P, Qiu Z, Du Y. Potassium channels and autism spectrum disorder: An overview. Int J Dev Neurosci 2021; 81:479-491. [PMID: 34008235 DOI: 10.1002/jdn.10123] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 05/08/2021] [Accepted: 05/11/2021] [Indexed: 11/07/2022] Open
Abstract
Autism spectrum disorder (ASD) comprises a group of neurodevelopmental disorders characterized by impaired social interaction and communication, and restricted, repetitive patterns of behaviors, interests, or activities. It had been demonstrated that potassium channels played a key role in regulating neuronal excitability, which was closely associated with neurological diseases including epilepsy, ataxia, myoclonus, and psychiatric disorders. In recent years, a growing body of evidence from whole-genome sequencing and whole-exome sequencing had identified several ASD susceptibility genes of potassium channels in ASD subjects. Genetically dysfunction of potassium channels may be involved in altered neuronal excitability and abnormal brain function in the pathogenesis of ASD. This review summarizes current findings on the features of ASD-risk genes (KCND2, KCNQ2, KCNQ3, KCNH5, KCNJ2, KCNJ10, and KCNMA1) and further expatiate their potential role in the pathogenicity of ASD.
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Affiliation(s)
- Peipei Cheng
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zilong Qiu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China.,Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai, China
| | - Yasong Du
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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6
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Liu G, Zhao H, Yan Z, Zhao S, Niu Y, Li X, Wang S, Yang Y, Liu S, Zhang TJ, Wu Z, Wu N. Whole-genome methylation analysis reveals novel epigenetic perturbations of congenital scoliosis. MOLECULAR THERAPY. NUCLEIC ACIDS 2021; 23:1281-1287. [PMID: 33717649 PMCID: PMC7907230 DOI: 10.1016/j.omtn.2021.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 02/05/2021] [Indexed: 11/24/2022]
Abstract
Congenital scoliosis (CS) is a congenital disease caused by malformations of vertebrae. Recent studies demonstrated that DNA modification could contribute to the pathogenesis of disease. This study aims to identify epigenetic perturbations that may contribute to the pathogenesis of CS. Four CS patients with hemivertebra were enrolled and underwent spine correction operations. DNA was extracted from the hemivertebrae and spinal process collected from the specimen during the hemivertebra resection. Genome-wide DNA methylation profiling was examined at base-pair resolution using whole-genome bisulfite sequencing (WGBS). We identified 343 genes with hyper-differentially methylated regions (DMRs) and 222 genes with hypo-DMRs, respectively. These genes were enriched in the mitogen-activated protein kinase (MAPK) signaling pathway, calcium signaling pathway, and axon guidance in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and were enriched in positive regulation of cell morphogenesis involved in differentiation, regulation of cell morphogenesis involved in differentiation, and regulation of neuron projection development in Biological Process of Gene Ontology (GO-BP) terms. Hyper-DMR-related genes, including IGHG1, IGHM, IGHG3, RNF213, and GSE1, and hypo DMR-related genes, including SORCS2, COL5A1, GRID1, RGS3, and ROBO2, may contribute to the pathogenesis of hemivertebra. The aberrant DNA methylation may be associated with the formation of hemivertebra and congenital scoliosis.
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Affiliation(s)
- Gang Liu
- Department of Orthopedic Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Key Laboratory of Big Data for Spinal Deformities, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Department of Breast Surgical Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Hengqiang Zhao
- Department of Orthopedic Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Key Laboratory of Big Data for Spinal Deformities, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Zihui Yan
- Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Sen Zhao
- Department of Orthopedic Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Key Laboratory of Big Data for Spinal Deformities, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China
| | - Yuchen Niu
- Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Xiaoxin Li
- Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Shengru Wang
- Department of Orthopedic Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Key Laboratory of Big Data for Spinal Deformities, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Key Laboratory of Big Data for Spinal Deformities, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Yang Yang
- Department of Orthopedic Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Key Laboratory of Big Data for Spinal Deformities, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Key Laboratory of Big Data for Spinal Deformities, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Sen Liu
- Department of Orthopedic Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Key Laboratory of Big Data for Spinal Deformities, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Key Laboratory of Big Data for Spinal Deformities, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Terry Jianguo Zhang
- Department of Orthopedic Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Key Laboratory of Big Data for Spinal Deformities, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Key Laboratory of Big Data for Spinal Deformities, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Zhihong Wu
- Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Key Laboratory of Big Data for Spinal Deformities, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Nan Wu
- Department of Orthopedic Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Key Laboratory of Big Data for Spinal Deformities, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.,Beijing Key Laboratory for Genetic Research of Skeletal Deformity, Beijing 100730, China.,Key Laboratory of Big Data for Spinal Deformities, Chinese Academy of Medical Sciences, Beijing 100730, China
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7
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Liu X, Liu C, Ye J, Zhang S, Wang K, Su R. Distribution of Acid Sensing Ion Channels in Axonal Growth Cones and Presynaptic Membrane of Cultured Hippocampal Neurons. Front Cell Neurosci 2020; 14:205. [PMID: 32733209 PMCID: PMC7358772 DOI: 10.3389/fncel.2020.00205] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/10/2020] [Indexed: 12/24/2022] Open
Abstract
Although acid-sensing ion channels (ASICs) are widely expressed in the central nervous system, their distribution and roles in axonal growth cones remain unclear. In this study, we examined ASIC localization and function in the axonal growth cones of cultured immature hippocampal neurons. Our immunocytochemical data showed that native and overexpressed ASIC1a and ASIC2a are both localized in growth cones of cultured young hippocampal neurons. Calcium imaging and electrophysiological assay results were utilized to validate their function. The calcium imaging test results indicated that the ASICs (primarily ASIC1a) present in growth cones mediate calcium influx despite the addition of voltage-gated Ca2+ channels antagonists and the depletion of intracellular calcium stores. The electrophysiological tests results suggested that a rapid decrease in extracellular pH at the growth cones of voltage-clamped neurons elicits inward currents that were blocked by bath application of the ASIC antagonist amiloride, showing that the ASICs expressed at growth cones are functional. The subsequent immuno-colocalization test results demonstrated that ASIC1a and ASIC2a are both colocalized with Neurofilament-H and Bassoon in mature hippocampal neurons. This finding demonstrated that after reaching maturity, ASIC1a and ASIC2a are both distributed in axons and the presynaptic membrane. Our data reveal the distribution of functional ASICs in growth cones of immature hippocampal neurons and the presence of ASICs in the axons and presynaptic membrane of mature hippocampal neurons, indicating a possible role for ASICs in axonal guidance, synapse formation and neurotransmitter release.
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Affiliation(s)
- Xiaoyan Liu
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Can Liu
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Jiamin Ye
- School of Pharmacy, North China University of Science and Technology, Tangshan, China
| | - Shuzhuo Zhang
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Kai Wang
- State Key Laboratory of Proteomics, National Center of Biomedical Analysis, Beijing, China
| | - Ruibin Su
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Beijing Institute of Pharmacology and Toxicology, Beijing, China
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8
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Chow LWC, Leung YM. The versatile Kv channels in the nervous system: actions beyond action potentials. Cell Mol Life Sci 2020; 77:2473-2482. [PMID: 31894358 PMCID: PMC11104815 DOI: 10.1007/s00018-019-03415-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 11/16/2019] [Accepted: 12/09/2019] [Indexed: 12/22/2022]
Abstract
Voltage-gated K+ (Kv) channel opening repolarizes excitable cells by allowing K+ efflux. Over the last two decades, multiple Kv functions in the nervous system have been found to be unrelated to or beyond the immediate control of excitability, such as shaping action potential contours or regulation of inter-spike frequency. These functions include neuronal exocytosis and neurite formation, neuronal cell death, regulation of astrocyte Ca2+, glial cell and glioma proliferation. Some of these functions have been shown to be independent of K+ conduction, that is, they suggest the non-canonical functions of Kv channels. In this review, we focus on neuronal or glial plasmalemmal Kv channel functions which are unrelated to shaping action potentials or immediate control of excitability. Similar functions in other cell types will be discussed to some extent in appropriate contexts.
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Affiliation(s)
- Louis W C Chow
- State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Macau, China
- UNIMED Medical Institute, Hong Kong, China
- Organisation for Oncology and Translational Research, Hong Kong, China
| | - Yuk- Man Leung
- Department of Physiology, China Medical University, Taichung, 40402, Taiwan.
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9
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Xu X, Mee T, Jia X. New era of optogenetics: from the central to peripheral nervous system. Crit Rev Biochem Mol Biol 2020; 55:1-16. [PMID: 32070147 DOI: 10.1080/10409238.2020.1726279] [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] [Indexed: 12/15/2022]
Abstract
Optogenetics has recently gained recognition as a biological technique to control the activity of cells using light stimulation. Many studies have applied optogenetics to cell lines in the central nervous system because it has the potential to elucidate neural circuits, treat neurological diseases and promote nerve regeneration. There have been fewer studies on the application of optogenetics in the peripheral nervous system. This review introduces the basic principles and approaches of optogenetics and summarizes the physiology and mechanism of opsins and how the technology enables bidirectional control of unique cell lines with superior spatial and temporal accuracy. Further, this review explores and discusses the therapeutic potential for the development of optogenetics and its capacity to revolutionize treatment for refractory epilepsy, depression, pain, and other nervous system disorders, with a focus on neural regeneration, especially in the peripheral nervous system. Additionally, this review synthesizes the latest preclinical research on optogenetic stimulation, including studies on non-human primates, summarizes the challenges, and highlights future perspectives. The potential of optogenetic stimulation to optimize therapy for peripheral nerve injuries (PNIs) is also highlighted. Optogenetic technology has already generated exciting, preliminary evidence, supporting its role in applications to several neurological diseases, including PNIs.
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Affiliation(s)
- Xiang Xu
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Thomas Mee
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Xiaofeng Jia
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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10
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Bioelectrical controls of morphogenesis: from ancient mechanisms of cell coordination to biomedical opportunities. Curr Opin Genet Dev 2019; 57:61-69. [PMID: 31442749 DOI: 10.1016/j.gde.2019.06.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 06/06/2019] [Accepted: 06/18/2019] [Indexed: 11/21/2022]
Abstract
Cell-to-cell communication is a cornerstone of multicellular existence. The ancient mechanism of sharing information between cells using the conductance of ions across cell membranes and the propagation of electrical signals through tissue space is a powerful means of efficiently controlling cell decisions and behaviors. Our understanding of how cells use changes in 'bioelectrical' signals to elicit systems-level responses has dramatically improved in recent years. We are now in a position to not just describe these changes, but to also predictively alter them to learn more about their importance for developmental biology and regenerative medicine. Recent work is helping researchers construct a more integrative view of how these simple controls can orchestrate downstream changes in protein signaling pathways and gene regulatory networks. In this review, we highlight experiments and analyses that have led to new insights in bioelectrical controls, specifically as key modulators of complex pattern formation and tissue regeneration. We also discuss opportunities for the development of new therapeutic approaches in regenerative medicine applications by exploiting this fundamental biological phenomenon.
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11
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Zemel BM, Ritter DM, Covarrubias M, Muqeem T. A-Type K V Channels in Dorsal Root Ganglion Neurons: Diversity, Function, and Dysfunction. Front Mol Neurosci 2018; 11:253. [PMID: 30127716 PMCID: PMC6088260 DOI: 10.3389/fnmol.2018.00253] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 07/04/2018] [Indexed: 12/13/2022] Open
Abstract
A-type voltage-gated potassium (Kv) channels are major regulators of neuronal excitability that have been mainly characterized in the central nervous system. By contrast, there is a paucity of knowledge about the molecular physiology of these Kv channels in the peripheral nervous system, including highly specialized and heterogenous dorsal root ganglion (DRG) neurons. Although all A-type Kv channels display pore-forming subunits with similar structural properties and fast inactivation, their voltage-, and time-dependent properties and modulation are significantly different. These differences ultimately determine distinct physiological roles of diverse A-type Kv channels, and how their dysfunction might contribute to neurological disorders. The importance of A-type Kv channels in DRG neurons is highlighted by recent studies that have linked their dysfunction to persistent pain sensitization. Here, we review the molecular neurophysiology of A-type Kv channels with an emphasis on those that have been identified and investigated in DRG nociceptors (Kv1.4, Kv3.4, and Kv4s). Also, we discuss evidence implicating these Kv channels in neuropathic pain resulting from injury, and present a perspective of outstanding challenges that must be tackled in order to discover novel treatments for intractable pain disorders.
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Affiliation(s)
- Benjamin M. Zemel
- Vollum Institute, Oregon Health and Science University, Portland, OR, United States
| | - David M. Ritter
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Manuel Covarrubias
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College and Jefferson College of Life Sciences at Thomas Jefferson University, Philadelphia, PA, United States
| | - Tanziyah Muqeem
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College and Jefferson College of Life Sciences at Thomas Jefferson University, Philadelphia, PA, United States
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