1
|
Faraji P, Kühn H, Ahmadian S. Multiple Roles of Apolipoprotein E4 in Oxidative Lipid Metabolism and Ferroptosis During the Pathogenesis of Alzheimer's Disease. J Mol Neurosci 2024; 74:62. [PMID: 38958788 PMCID: PMC11222241 DOI: 10.1007/s12031-024-02224-4] [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: 01/08/2024] [Accepted: 04/14/2024] [Indexed: 07/04/2024]
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disease worldwide and has a great socio-economic impact. Modified oxidative lipid metabolism and dysregulated iron homeostasis have been implicated in the pathogenesis of this disorder, but the detailed pathophysiological mechanisms still remain unclear. Apolipoprotein E (APOE) is a lipid-binding protein that occurs in large quantities in human blood plasma, and a polymorphism of the APOE gene locus has been identified as risk factors for AD. The human genome involves three major APOE alleles (APOE2, APOE3, APOE4), which encode for three subtly distinct apolipoprotein E isoforms (APOE2, APOE3, APOE4). The canonic function of these apolipoproteins is lipid transport in blood and brain, but APOE4 allele carriers have a much higher risk for AD. In fact, about 60% of clinically diagnosed AD patients carry at least one APOE4 allele in their genomes. Although the APOE4 protein has been implicated in pathophysiological key processes of AD, such as extracellular beta-amyloid (Aβ) aggregation, mitochondrial dysfunction, neuroinflammation, formation of neurofibrillary tangles, modified oxidative lipid metabolism, and ferroptotic cell death, the underlying molecular mechanisms are still not well understood. As for all mammalian cells, iron plays a crucial role in neuronal functions and dysregulation of iron homeostasis has also been implicated in the pathogenesis of AD. Imbalances in iron homeostasis and impairment of the hydroperoxy lipid-reducing capacity induce cellular dysfunction leading to neuronal ferroptosis. In this review, we summarize the current knowledge on APOE4-related oxidative lipid metabolism and the potential role of ferroptosis in the pathogenesis of AD. Pharmacological interference with these processes might offer innovative strategies for therapeutic interventions.
Collapse
Affiliation(s)
- Parisa Faraji
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Hartmut Kühn
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany.
| | - Shahin Ahmadian
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
| |
Collapse
|
2
|
Chen J, Liu X, Liu C, Tang L, Bu T, Jiang B, Qing Y, Xie Y, Wang Y, Shan Y, Li R, Ye C, Liao L. Reconfigurable Ag/HfO 2/NiO/Pt Memristors with Stable Synchronous Synaptic and Neuronal Functions for Renewable Homogeneous Neuromorphic Computing System. NANO LETTERS 2024; 24:5371-5378. [PMID: 38647348 DOI: 10.1021/acs.nanolett.4c01319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Artificial synapses and bionic neurons offer great potential in highly efficient computing paradigms. However, complex requirements for specific electronic devices in neuromorphic computing have made memristors face the challenge of process simplification and universality. Herein, reconfigurable Ag/HfO2/NiO/Pt memristors are designed for feasible switching between volatile and nonvolatile modes by compliance current controlled Ag filaments, which enables stable and reconfigurable synaptic and neuronal functions. A neuromorphic computing system effectively replicates the biological synaptic weight alteration and continuously accomplishes excitation and reset of artificial neurons, which consist of bionic synapses and artificial neurons based on isotype Ag/HfO2/NiO/Pt memristors. This reconfigurable electrical performance of the Ag/HfO2/NiO/Pt memristors takes advantage of simplified hardware design and delivers integrated circuits with high density, which exhibits great potency for future neural networks.
Collapse
Affiliation(s)
- Jiaqi Chen
- Key Laboratory of Intelligent Sensing System and Security, Ministry of Education, School of Microelectronics, Hubei University, Wuhan 430062, China
| | - Xingqiang Liu
- Changsha Semiconductor Technology and Application Research Institute, Engineering Research Center of Advanced Semiconductor Technology, College of Semiconductor (College of Integrated Circuit), Hunan University, Changsha 410082, China
| | - Chang Liu
- Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education & Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Lin Tang
- Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education & Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Tong Bu
- Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education & Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Bei Jiang
- Key Laboratory of Intelligent Sensing System and Security, Ministry of Education, School of Microelectronics, Hubei University, Wuhan 430062, China
- Changsha Semiconductor Technology and Application Research Institute, Engineering Research Center of Advanced Semiconductor Technology, College of Semiconductor (College of Integrated Circuit), Hunan University, Changsha 410082, China
| | - Yahui Qing
- Key Laboratory of Intelligent Sensing System and Security, Ministry of Education, School of Microelectronics, Hubei University, Wuhan 430062, China
| | - Yulu Xie
- Key Laboratory of Intelligent Sensing System and Security, Ministry of Education, School of Microelectronics, Hubei University, Wuhan 430062, China
| | - Yong Wang
- Key Laboratory of Intelligent Sensing System and Security, Ministry of Education, School of Microelectronics, Hubei University, Wuhan 430062, China
| | - Yongtao Shan
- Key Laboratory of Intelligent Sensing System and Security, Ministry of Education, School of Microelectronics, Hubei University, Wuhan 430062, China
| | - Ruxin Li
- Key Laboratory of Intelligent Sensing System and Security, Ministry of Education, School of Microelectronics, Hubei University, Wuhan 430062, China
| | - Cong Ye
- Key Laboratory of Intelligent Sensing System and Security, Ministry of Education, School of Microelectronics, Hubei University, Wuhan 430062, China
| | - Lei Liao
- Changsha Semiconductor Technology and Application Research Institute, Engineering Research Center of Advanced Semiconductor Technology, College of Semiconductor (College of Integrated Circuit), Hunan University, Changsha 410082, China
| |
Collapse
|
3
|
Jiang Q, Wu KLK, Hu XQ, Cheung MH, Chen W, Ma CW, Shum DKY, Chan YS. Neonatal GABAergic transmission primes vestibular gating of output for adult spatial navigation. Cell Mol Life Sci 2024; 81:147. [PMID: 38502309 PMCID: PMC10951018 DOI: 10.1007/s00018-024-05170-x] [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: 06/12/2023] [Revised: 01/26/2024] [Accepted: 02/07/2024] [Indexed: 03/21/2024]
Abstract
GABAergic interneurons are poised with the capacity to shape circuit output via inhibitory gating. How early in the development of medial vestibular nucleus (MVN) are GABAergic neurons recruited for feedforward shaping of outputs to higher centers for spatial navigation? The role of early GABAergic transmission in assembling vestibular circuits for spatial navigation was explored by neonatal perturbation. Immunohistochemistry and confocal imaging were utilized to reveal the expression of parvalbumin (PV)-expressing MVN neurons and their perineuronal nets. Whole-cell patch-clamp recording, coupled with optogenetics, was conducted in vitro to examine the synaptic function of MVN circuitry. Chemogenetic targeting strategy was also employed in vivo to manipulate neuronal activity during navigational tests. We found in rats a neonatal critical period before postnatal day (P) 8 in which competitive antagonization of GABAergic transmission in the MVN retarded maturation of inhibitory neurotransmission, as evidenced by deranged developmental trajectory for excitation/inhibition ratio and an extended period of critical period-like plasticity in GABAergic transmission. Despite increased number of PV-expressing GABAergic interneurons in the MVN, optogenetic-coupled patch-clamp recording indicated null-recruitment of these neurons in tuning outputs along the ascending vestibular pathway. Such perturbation not only offset output dynamics of ascending MVN output neurons, but was further accompanied by impaired vestibular-dependent navigation in adulthood. The same perturbations were however non-consequential when applied after P8. Results highlight neonatal GABAergic transmission as key to establishing feedforward output dynamics to higher brain centers for spatial cognition and navigation.
Collapse
Affiliation(s)
- Qiufen Jiang
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, Hong Kong SAR, People's Republic of China
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Kenneth Lap-Kei Wu
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, Hong Kong SAR, People's Republic of China
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Xiao-Qian Hu
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, Hong Kong SAR, People's Republic of China
- Department of Rehabilitation Medicine, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Man-Him Cheung
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, Hong Kong SAR, People's Republic of China
| | - Wenqiang Chen
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, Hong Kong SAR, People's Republic of China
- Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA
| | - Chun-Wai Ma
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, Hong Kong SAR, People's Republic of China
| | - Daisy Kwok-Yan Shum
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, Hong Kong SAR, People's Republic of China.
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR, People's Republic of China.
| | - Ying-Shing Chan
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, Hong Kong SAR, People's Republic of China.
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR, People's Republic of China.
| |
Collapse
|
4
|
Khodaie B, Edelmann E, Leßmann V. Distinct GABAergic modulation of timing-dependent LTP in CA1 pyramidal neurons along the longitudinal axis of the mouse hippocampus. iScience 2024; 27:109320. [PMID: 38487018 PMCID: PMC10937841 DOI: 10.1016/j.isci.2024.109320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 01/25/2024] [Accepted: 02/20/2024] [Indexed: 03/17/2024] Open
Abstract
Synaptic plasticity in the hippocampus underlies episodic memory formation, with dorsal hippocampus being instrumental for spatial memory whereas ventral hippocampus is crucial for emotional learning. Here, we studied how GABAergic inhibition regulates physiologically relevant low repeat spike timing-dependent LTP (t-LTP) at Schaffer collateral-CA1 synapses along the dorsoventral hippocampal axis. We used two t-LTP protocols relying on only 6 repeats of paired spike-firing in pre- and postsynaptic cells within 10 s that differ in postsynaptic firing patterns. GABAA receptor mechanisms played a greater role in blocking 6× 1:1 t-LTP that recruits single postsynaptic action potentials. 6× 1:4 t-LTP that depends on postsynaptic burst-firing unexpectedly required intact GABAB receptor signaling. The magnitude of both t-LTP-forms decreased along the dorsoventral axis, despite increasing excitability and basal synaptic strength in this direction. This suggests that GABAergic inhibition contributes to the distinct roles of dorsal and ventral hippocampus in memory formation.
Collapse
Affiliation(s)
- Babak Khodaie
- Institut für Physiologie, Otto-von-Guericke-Universität (OVGU), Medizinische Fakultät, 39120 Magdeburg, Germany
- OVGU International ESF-funded Graduate School ABINEP, 39104 Magdeburg, Germany
| | - Elke Edelmann
- Institut für Physiologie, Otto-von-Guericke-Universität (OVGU), Medizinische Fakultät, 39120 Magdeburg, Germany
- Center for Behavioral Brain Sciences, 39104 Magdeburg, Germany
- OVGU International ESF-funded Graduate School ABINEP, 39104 Magdeburg, Germany
| | - Volkmar Leßmann
- Institut für Physiologie, Otto-von-Guericke-Universität (OVGU), Medizinische Fakultät, 39120 Magdeburg, Germany
- Center for Behavioral Brain Sciences, 39104 Magdeburg, Germany
- OVGU International ESF-funded Graduate School ABINEP, 39104 Magdeburg, Germany
- DZPG (German Center of Mental Health), partner site Halle/Jena/Magdeburg (CIRC), Magdeburg, Germany
| |
Collapse
|
5
|
Yang S, Kim T, Kim S, Chung D, Kim TH, Lee JK, Kim S, Ismail M, Mahata C, Kim S, Cho S. Synaptic plasticity and non-volatile memory characteristics in TiN-nanocrystal-embedded 3D vertical memristor-based synapses for neuromorphic systems. NANOSCALE 2023; 15:13239-13251. [PMID: 37525621 DOI: 10.1039/d3nr01930f] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Although vertical configurations for high-density storage require challenging process steps, such as etching high aspect ratios and atomic layer deposition (ALD), they are more affordable with a relatively simple lithography process and have been employed in many studies. Herein, the potential of memristors with CMOS-compatible 3D vertical stacked structures of Pt/Ti/HfOx/TiN-NCs/HfOx/TiN is examined for use in neuromorphic systems. The electrical characteristics (including I-V properties, retention, and endurance) were investigated for both planar single cells and vertical resistive random-access memory (VRRAM) cells at each layer, demonstrating their outstanding non-volatile memory capabilities. In addition, various synaptic functions (including potentiation and depression) under different pulse schemes, excitatory postsynaptic current (EPSC), and spike-timing-dependent plasticity (STDP) were investigated. In pattern recognition simulations, an improved recognition rate was achieved by the linearly changing conductance, which was enhanced by the incremental pulse scheme. The achieved results demonstrated the feasibility of employing VRRAM with TiN nanocrystals in neuromorphic systems that resemble the human brain.
Collapse
Affiliation(s)
- Seyeong Yang
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea.
| | - Taegyun Kim
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea.
| | - Sunghun Kim
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea.
| | - Daewon Chung
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea.
| | - Tae-Hyeon Kim
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Jung Kyu Lee
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea.
| | - Sungjoon Kim
- Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Muhammad Ismail
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea.
| | - Chandreswar Mahata
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea.
| | - Sungjun Kim
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea.
| | - Seongjae Cho
- Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, South Korea.
| |
Collapse
|
6
|
Pressey JC, de Saint-Rome M, Raveendran VA, Woodin MA. Chloride transporters controlling neuronal excitability. Physiol Rev 2023; 103:1095-1135. [PMID: 36302178 DOI: 10.1152/physrev.00025.2021] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Synaptic inhibition plays a crucial role in regulating neuronal excitability, which is the foundation of nervous system function. This inhibition is largely mediated by the neurotransmitters GABA and glycine that activate Cl--permeable ion channels, which means that the strength of inhibition depends on the Cl- gradient across the membrane. In neurons, the Cl- gradient is primarily mediated by two secondarily active cation-chloride cotransporters (CCCs), NKCC1 and KCC2. CCC-mediated regulation of the neuronal Cl- gradient is critical for healthy brain function, as dysregulation of CCCs has emerged as a key mechanism underlying neurological disorders including epilepsy, neuropathic pain, and autism spectrum disorder. This review begins with an overview of neuronal chloride transporters before explaining the dependent relationship between these CCCs, Cl- regulation, and inhibitory synaptic transmission. We then discuss the evidence for how CCCs can be regulated, including by activity and their protein interactions, which underlie inhibitory synaptic plasticity. For readers who may be interested in conducting experiments on CCCs and neuronal excitability, we have included a section on techniques for estimating and recording intracellular Cl-, including their advantages and limitations. Although the focus of this review is on neurons, we also examine how Cl- is regulated in glial cells, which in turn regulate neuronal excitability through the tight relationship between this nonneuronal cell type and synapses. Finally, we discuss the relatively extensive and growing literature on how CCC-mediated neuronal excitability contributes to neurological disorders.
Collapse
Affiliation(s)
- Jessica C Pressey
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Miranda de Saint-Rome
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Vineeth A Raveendran
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Melanie A Woodin
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
7
|
Ryner RF, Derera ID, Armbruster M, Kansara A, Sommer ME, Pirone A, Noubary F, Jacob M, Dulla CG. Cortical Parvalbumin-Positive Interneuron Development and Function Are Altered in the APC Conditional Knockout Mouse Model of Infantile and Epileptic Spasms Syndrome. J Neurosci 2023; 43:1422-1440. [PMID: 36717229 PMCID: PMC9987578 DOI: 10.1523/jneurosci.0572-22.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 11/14/2022] [Accepted: 12/22/2022] [Indexed: 02/01/2023] Open
Abstract
Infantile and epileptic spasms syndrome (IESS) is a childhood epilepsy syndrome characterized by infantile or late-onset spasms, abnormal neonatal EEG, and epilepsy. Few treatments exist for IESS, clinical outcomes are poor, and the molecular and circuit-level etiologies of IESS are not well understood. Multiple human IESS risk genes are linked to Wnt/β-catenin signaling, a pathway that controls developmental transcriptional programs and promotes glutamatergic excitation via β-catenin's role as a synaptic scaffold. We previously showed that deleting adenomatous polyposis coli (APC), a component of the β-catenin destruction complex, in excitatory neurons (APC cKO mice, APCfl/fl x CaMKIIαCre) increased β-catenin levels in developing glutamatergic neurons and led to infantile behavioral spasms, abnormal neonatal EEG, and adult epilepsy. Here, we tested the hypothesis that the development of GABAergic interneurons (INs) is disrupted in APC cKO male and female mice. IN dysfunction is implicated in human IESS, is a feature of other rodent models of IESS, and may contribute to the manifestation of spasms and seizures. We found that parvalbumin-positive INs (PV+ INs), an important source of cortical inhibition, were decreased in number, underwent disproportionate developmental apoptosis, and had altered dendrite morphology at P9, the peak of behavioral spasms. PV+ INs received excessive excitatory input, and their intrinsic ability to fire action potentials was reduced at all time points examined (P9, P14, P60). Subsequently, GABAergic transmission onto pyramidal neurons was uniquely altered in the somatosensory cortex of APC cKO mice at all ages, with both decreased IPSC input at P14 and enhanced IPSC input at P9 and P60. These results indicate that inhibitory circuit dysfunction occurs in APC cKOs and, along with known changes in excitation, may contribute to IESS-related phenotypes.SIGNIFICANCE STATEMENT Infantile and epileptic spasms syndrome (IESS) is a devastating epilepsy with limited treatment options and poor clinical outcomes. The molecular, cellular, and circuit disruptions that cause infantile spasms and seizures are largely unknown, but inhibitory GABAergic interneuron dysfunction has been implicated in rodent models of IESS and may contribute to human IESS. Here, we use a rodent model of IESS, the APC cKO mouse, in which β-catenin signaling is increased in excitatory neurons. This results in altered parvalbumin-positive GABAergic interneuron development and GABAergic synaptic dysfunction throughout life, showing that pathology arising in excitatory neurons can initiate long-term interneuron dysfunction. Our findings further implicate GABAergic dysfunction in IESS, even when pathology is initiated in other neuronal types.
Collapse
Affiliation(s)
- Rachael F Ryner
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111
- Cell, Molecular, and Developmental Biology Graduate Program, Tufts Graduate School of Biomedical Sciences, Boston, Massachusetts 02111
| | - Isabel D Derera
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Moritz Armbruster
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Anar Kansara
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Mary E Sommer
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Antonella Pirone
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Farzad Noubary
- Department of Health Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts 02115
| | - Michele Jacob
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Chris G Dulla
- Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111
| |
Collapse
|
8
|
O'Dell DE, Smith-Bell CA, Enquist LW, Engel EA, Schreurs BG. Eyeblink tract tracing with two strains of herpes simplex virus 1. Brain Res 2022; 1793:148040. [PMID: 35932812 DOI: 10.1016/j.brainres.2022.148040] [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: 03/31/2022] [Revised: 07/20/2022] [Accepted: 08/01/2022] [Indexed: 11/18/2022]
Abstract
BACKGROUND Neuroinvasive herpes simplex-1 (HSV-1) isolates including H129 and McIntyre cross at or near synapses labeling higher-order neurons directly connected to infected cells. H129 spreads predominately in the anterograde direction while McIntyre strains spread only in the retrograde direction. However, it is unknown if neurons are functional once infected with derivatives of H129 or McIntyre. NEW METHOD We describe a previously unpublished HSV-1 recombinant derived from H129 (HSV-373) expressing mCherry fluorescent reporters and one new McIntyre recombinant (HSV-780) expressing the mCherry fluorophore and demonstrate how infections affect neuron viability. RESULTS AND COMPARISON WITH EXISTING METHODS Each recombinant virus behaved similarly and spread to the target 4 days post-infection. We tested H129 recombinant infected neurons for neurodegeneration using Fluoro-jade C and found them to be necrotic as a result of viral infection. We performed dual inoculations with both HSV-772 and HSV-780 to identify cells comprising both the anterograde pathway and the retrograde pathway, respectively, of our circuit of study. We examined the presence of postsynaptic marker PSD-95, which plays a role in synaptic plasticity, in HSV-772 infected and in dual-infected rats (HSV-772 and HSV-780). PSD-95 reactivity decreased in HSV-772-infected neurons and dual-infected tissue had no PSD-95 reactivity. CONCLUSIONS Infection by these new recombinant viruses traced the circuit of interest but functional studies of the cells comprising the pathway were not possible because viral-infected neurons died as a result of necrosis or were stripped of PSD-95 by the time the viral labels reached the target.
Collapse
Affiliation(s)
- Deidre E O'Dell
- Department of Neuroscience, Rockefeller Neuroscience Institute, United States; West Virginia University, Morgantown, WV 26505, United States.
| | - Carrie A Smith-Bell
- Department of Neuroscience, Rockefeller Neuroscience Institute, United States; West Virginia University, Morgantown, WV 26505, United States
| | - Lynn W Enquist
- Department of Molecular Biology, United States; Princeton Neuroscience Institute, United States; Princeton University, Princeton, NJ 08544, United States
| | - Esteban A Engel
- Princeton Neuroscience Institute, United States; Princeton University, Princeton, NJ 08544, United States
| | - Bernard G Schreurs
- Department of Neuroscience, Rockefeller Neuroscience Institute, United States; West Virginia University, Morgantown, WV 26505, United States.
| |
Collapse
|
9
|
Lima-Silveira L, Hasser EM, Kline DD. Cardiovascular deconditioning increases GABA signaling in the nucleus tractus solitarii. J Neurophysiol 2022; 128:28-39. [PMID: 35642806 PMCID: PMC9236861 DOI: 10.1152/jn.00102.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The nucleus tractus solitarii (nTS) is the major integrative brainstem region for autonomic modulation and processing of cardiovascular reflexes. GABA and glutamate are the main inhibitory and excitatory neurotransmitters, respectively, within this nucleus. Alterations in the GABA-glutamate regulation in the nTS are related to numerous cardiovascular comorbidities. Bedridden individuals and people exposed to microgravity exhibit dysautonomia and cardiovascular deconditioning that are mimicked in the hindlimb unloading (HU) rat model. We have previously shown in the nTS that HU increases glutamatergic neurotransmission yet decreases neuronal excitability. In this study, we investigated the effects of HU on nTS GABAergic neurotransmission. We hypothesized that HU potentiates GABA signaling via increased GABAergic release and postsynaptic GABA receptor expression. Following HU or control postural exposure, GABAergic neurotransmission was assessed using whole cell patch clamp whereas the magnitude of GABA release was evaluated via an intensity-based GABA sensing fluorescence reporter (iGABASnFR). In response to GABA interneuron stimulation, the evoked inhibitory postsynaptic current (nTS-IPSC) amplitude and area, as well as iGABASnFR fluorescence, were greater in HU than in control. HU also elevated the frequency but not the amplitude of spontaneous miniature IPSCs. Picoapplication of GABA produced similar postsynaptic current responses in nTS neurons of HU and control. Moreover, HU did not alter GABAA receptor α1 subunit expression, indicating minimal alterations in postsynaptic membrane receptor expression. These results indicate that HU increases GABAergic signaling in the nTS likely via augmented release of GABA from presynaptic terminals. Altogether, our data indicate GABA plasticity contributes to the autonomic and cardiovascular alterations following cardiovascular deconditioning (CVD).NEW & NOTEWORTHY Gravity influences distribution of blood volume and autonomic function. Microgravity and prolonged bed rest induce cardiovascular deconditioning (CVD). We used hindlimb unloading (HU), a rat analog for bed rest, to investigate CVD-induced neuroplasticity in the brainstem. Our data demonstrate that HU increases GABA modulation of nucleus tractus solitarii (nTS) neurons via presynaptic plasticity. Given the importance of nTS in integrating cardiovascular reflexes, this study provides new evidence on the central mechanisms behind CVD following HU.
Collapse
Affiliation(s)
- Ludmila Lima-Silveira
- 1Department of Biomedical Sciences, University of Missouri, Columbia, Missouri,3Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| | - Eileen M. Hasser
- 1Department of Biomedical Sciences, University of Missouri, Columbia, Missouri,2Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri,3Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| | - David D. Kline
- 1Department of Biomedical Sciences, University of Missouri, Columbia, Missouri,2Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri,3Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| |
Collapse
|
10
|
Buontempo S, Laise P, Hughes JM, Trattaro S, Das V, Rencurel C, Testa G. EZH2-Mediated H3K27me3 Targets Transcriptional Circuits of Neuronal Differentiation. Front Neurosci 2022; 16:814144. [PMID: 35645710 PMCID: PMC9133892 DOI: 10.3389/fnins.2022.814144] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 02/11/2022] [Indexed: 12/27/2022] Open
Abstract
The Polycomb Repressive Complex 2 (PRC2) plays important roles in the epigenetic regulation of cellular development and differentiation through H3K27me3-dependent transcriptional repression. Aberrant PRC2 activity has been associated with cancer and neurodevelopmental disorders, particularly with respect to the malfunction of sits catalytic subunit EZH2. Here, we investigated the role of the EZH2-mediated H3K27me3 apposition in neuronal differentiation. We made use of a transgenic mouse model harboring Ezh2 conditional KO alleles to derive embryonic stem cells and differentiate them into glutamatergic neurons. Time course transcriptomics and epigenomic analyses of H3K27me3 in absence of EZH2 revealed a significant dysregulation of molecular networks affecting the glutamatergic differentiation trajectory that resulted in: (i) the deregulation of transcriptional circuitries related to neuronal differentiation and synaptic plasticity, in particular LTD, as a direct effect of EZH2 loss and (ii) the appearance of a GABAergic gene expression signature during glutamatergic neuron differentiation. These results expand the knowledge about the molecular pathways targeted by Polycomb during glutamatergic neuron differentiation.
Collapse
Affiliation(s)
- Serena Buontempo
- Department of Experimental Oncology, European Institute of Oncology IRCCS, Milan, Italy
| | - Pasquale Laise
- Department of Experimental Oncology, European Institute of Oncology IRCCS, Milan, Italy
| | - James M. Hughes
- Department of Experimental Oncology, European Institute of Oncology IRCCS, Milan, Italy
| | - Sebastiano Trattaro
- Department of Experimental Oncology, European Institute of Oncology IRCCS, Milan, Italy
- Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
- Human Technopole, Milan, Italy
| | - Vivek Das
- Department of Experimental Oncology, European Institute of Oncology IRCCS, Milan, Italy
| | - Chantal Rencurel
- Department of Structural Biology and Biophysics, Biozentrum of the University of Basel, Basel, Switzerland
| | - Giuseppe Testa
- Department of Experimental Oncology, European Institute of Oncology IRCCS, Milan, Italy
- Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
- Human Technopole, Milan, Italy
- *Correspondence: Giuseppe Testa,
| |
Collapse
|
11
|
Montanari M, Martella G, Bonsi P, Meringolo M. Autism Spectrum Disorder: Focus on Glutamatergic Neurotransmission. Int J Mol Sci 2022; 23:ijms23073861. [PMID: 35409220 PMCID: PMC8998955 DOI: 10.3390/ijms23073861] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/24/2022] [Accepted: 03/29/2022] [Indexed: 12/16/2022] Open
Abstract
Disturbances in the glutamatergic system have been increasingly documented in several neuropsychiatric disorders, including autism spectrum disorder (ASD). Glutamate-centered theories of ASD are based on evidence from patient samples and postmortem studies, as well as from studies documenting abnormalities in glutamatergic gene expression and metabolic pathways, including changes in the gut microbiota glutamate metabolism in patients with ASD. In addition, preclinical studies on animal models have demonstrated glutamatergic neurotransmission deficits and altered expression of glutamate synaptic proteins. At present, there are no approved glutamatergic drugs for ASD, but several ongoing clinical trials are currently focusing on evaluating in autistic patients glutamatergic pharmaceuticals already approved for other conditions. In this review, we provide an overview of the literature concerning the role of glutamatergic neurotransmission in the pathophysiology of ASD and as a potential target for novel treatments.
Collapse
Affiliation(s)
- Martina Montanari
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00179 Rome, Italy; (M.M.); (G.M.)
- Department of Systems Neuroscience, University Tor Vergata, 00133 Rome, Italy
| | - Giuseppina Martella
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00179 Rome, Italy; (M.M.); (G.M.)
| | - Paola Bonsi
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00179 Rome, Italy; (M.M.); (G.M.)
- Correspondence: (P.B.); (M.M.)
| | - Maria Meringolo
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00179 Rome, Italy; (M.M.); (G.M.)
- Correspondence: (P.B.); (M.M.)
| |
Collapse
|
12
|
Kourosh-Arami M, Hosseini N, Komaki A. Brain is modulated by neuronal plasticity during postnatal development. J Physiol Sci 2021; 71:34. [PMID: 34789147 PMCID: PMC10716960 DOI: 10.1186/s12576-021-00819-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 10/27/2021] [Indexed: 11/10/2022]
Abstract
Neuroplasticity is referred to the ability of the nervous system to change its structure or functions as a result of former stimuli. It is a plausible mechanism underlying a dynamic brain through adaptation processes of neural structure and activity patterns. Nevertheless, it is still unclear how the plastic neural systems achieve and maintain their equilibrium. Additionally, the alterations of balanced brain dynamics under different plasticity rules have not been explored either. Therefore, the present article primarily aims to review recent research studies regarding homosynaptic and heterosynaptic neuroplasticity characterized by the manipulation of excitatory and inhibitory synaptic inputs. Moreover, it attempts to understand different mechanisms related to the main forms of synaptic plasticity at the excitatory and inhibitory synapses during the brain development processes. Hence, this study comprised surveying those articles published since 1988 and available through PubMed, Google Scholar and science direct databases on a keyword-based search paradigm. All in all, the study results presented extensive and corroborative pieces of evidence for the main types of plasticity, including the long-term potentiation (LTP) and long-term depression (LTD) of the excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs).
Collapse
Affiliation(s)
- Masoumeh Kourosh-Arami
- Department of Neuroscience, School of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran.
| | - Nasrin Hosseini
- Neuroscience Research Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Alireza Komaki
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| |
Collapse
|
13
|
GSK3 as a Regulator of Cytoskeleton Architecture: Consequences for Health and Disease. Cells 2021; 10:cells10082092. [PMID: 34440861 PMCID: PMC8393567 DOI: 10.3390/cells10082092] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/06/2021] [Accepted: 08/12/2021] [Indexed: 12/17/2022] Open
Abstract
Glycogen synthase kinase 3 (GSK3) was initially isolated as a critical protein in energy metabolism. However, subsequent studies indicate that GSK-3 is a multi-tasking kinase that links numerous signaling pathways in a cell and plays a vital role in the regulation of many aspects of cellular physiology. As a regulator of actin and tubulin cytoskeleton, GSK3 influences processes of cell polarization, interaction with the extracellular matrix, and directional migration of cells and their organelles during the growth and development of an animal organism. In this review, the roles of GSK3–cytoskeleton interactions in brain development and pathology, migration of healthy and cancer cells, and in cellular trafficking of mitochondria will be discussed.
Collapse
|
14
|
Wang YT, Wang XL, Feng ST, Chen NH, Wang ZZ, Zhang Y. Novel rapid-acting glutamatergic modulators: Targeting the synaptic plasticity in depression. Pharmacol Res 2021; 171:105761. [PMID: 34242798 DOI: 10.1016/j.phrs.2021.105761] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 07/04/2021] [Accepted: 07/05/2021] [Indexed: 02/07/2023]
Abstract
Major depressive disorder (MDD) is severely prevalent, and conventional monoaminergic antidepressants gradually exhibit low therapeutic efficiency, especially for patients with treatment-resistant depression. A neuroplasticity hypothesis is an emerging advancement in the mechanism of depression, mainly expressed in the glutamate system, e.g., glutamate receptors and signaling. Dysfunctional glutamatergic neurotransmission is currently considered to be closely associated with the pathophysiology of MDD. Biological function, pharmacological action, and signal attributes in the glutamate system both regulate the neural process. Specific functional subunits could be therapeutic targets to explore the novel glutamatergic modulators, which have fast-acting, and relatively sustained antidepressant effects. Here, the present review summarizes the pathophysiology of MDD found in the glutamate system, exploring the role of glutamate receptors and their downstream effects. These convergent mechanisms have prompted the development of other modulators targeting on glutamate system, including N-methyl-d-aspartate receptor antagonists, selective GluN2B-specific antagonists, glycine binding site agents, and regulators of metabotropic glutamate receptors. Relevant researches underly the putative mechanisms of these drugs, which reverse the damage of depression by regulating glutamatergic neurotransmission. It also provides further insight into the mechanism of depression and exploring potential targets for novel agent development.
Collapse
Affiliation(s)
- Ya-Ting Wang
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing 102488, China
| | - Xiao-Le Wang
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing 102488, China
| | - Si-Tong Feng
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing 102488, China
| | - Nai-Hong Chen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Zhen-Zhen Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Yi Zhang
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing 102488, China.
| |
Collapse
|
15
|
Graeve A, Ioannidou I, Reinhard J, Görl DM, Faissner A, Weiss LC. Brain volume increase and neuronal plasticity underly predator-induced morphological defense expression in Daphnia longicephala. Sci Rep 2021; 11:12612. [PMID: 34131219 PMCID: PMC8206331 DOI: 10.1038/s41598-021-92052-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 06/03/2021] [Indexed: 12/23/2022] Open
Abstract
Predator-induced phenotypic plasticity describes the ability of prey to respond to an increased predation risk by developing adaptive phenotypes. Upon the perception of chemical predator cues, the freshwater crustacean Daphnia longicephala develops defensive crests against its predator Notonecta spec. (Heteroptera). Chemical predator perception initiates a cascade of biological reactions that leads to the development of these morphological features. Neuronal signaling is a central component in this series, however how the nervous system perceives and integrates environmental signals is not well understood. As neuronal activity is often accompanied by functional and structural plasticity of the nervous system, we hypothesized that predator perception is associated with structural and functional changes of nervous tissues. We observe structural plasticity as a volume increase of the central brain, which is independent of the total number of brain cells. In addition, we find functional plasticity in form of an increased number of inhibitory post-synaptic sites during the initial stage of defense development. Our results indicate a structural rewiring of nerve-cell connections upon predator perception and provide important insights into how the nervous system of prey species interprets predator cues and develops cost-benefit optimized defenses.
Collapse
Affiliation(s)
- A Graeve
- Department of Animal Ecology, Evolution and Biodiversity, Ruhr-University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - I Ioannidou
- Department of Animal Ecology, Evolution and Biodiversity, Ruhr-University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - J Reinhard
- Department of Cell Morphology and Molecular Neurobiology, Ruhr-University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - D M Görl
- Department of Animal Ecology, Evolution and Biodiversity, Ruhr-University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - A Faissner
- Department of Cell Morphology and Molecular Neurobiology, Ruhr-University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - L C Weiss
- Department of Animal Ecology, Evolution and Biodiversity, Ruhr-University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany.
| |
Collapse
|
16
|
Thompson BL, Oscar-Berman M, Kaplan GB. Opioid-induced structural and functional plasticity of medium-spiny neurons in the nucleus accumbens. Neurosci Biobehav Rev 2021; 120:417-430. [PMID: 33152423 PMCID: PMC7855607 DOI: 10.1016/j.neubiorev.2020.10.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/16/2020] [Accepted: 10/20/2020] [Indexed: 12/21/2022]
Abstract
Opioid Use Disorder (OUD) is a chronic relapsing clinical condition with tremendous morbidity and mortality that frequently persists, despite treatment, due to an individual's underlying psychological, neurobiological, and genetic vulnerabilities. Evidence suggests that these vulnerabilities may have neurochemical, cellular, and molecular bases. Key neuroplastic events within the mesocorticolimbic system that emerge through chronic exposure to opioids may have a determinative influence on behavioral symptoms associated with OUD. In particular, structural and functional alterations in the dendritic spines of medium spiny neurons (MSNs) within the nucleus accumbens (NAc) and its dopaminergic projections from the ventral tegmental area (VTA) are believed to facilitate these behavioral sequelae. Additionally, glutamatergic neurons from the prefrontal cortex, the basolateral amygdala, the hippocampus, and the thalamus project to these same MSNs, providing an enriched target for synaptic plasticity. Here, we review literature related to neuroadaptations in NAc MSNs from dopaminergic and glutamatergic pathways in OUD. We also describe new findings related to transcriptional, epigenetic, and molecular mechanisms in MSN plasticity in the different stages of OUD.
Collapse
Affiliation(s)
- Benjamin L Thompson
- Department of Radiology & Biomedical Imaging, Yale School of Medicine, New Haven, CT, 06520, USA; Research Service, VA Boston Healthcare System, 150 South Huntington Avenue, Boston, MA 02130, USA.
| | - Marlene Oscar-Berman
- Research Service, VA Boston Healthcare System, 150 South Huntington Avenue, Boston, MA 02130, USA; Department of Anatomy & Neurobiology, Boston University School of Medicine, 72 East Concord Street, Boston, MA, 02118, USA; Department of Psychiatry, Boston University School of Medicine, 720 Harrison Avenue, Boston, MA, 02118, USA; Department of Neurology, Boston University School of Medicine, Boston University Medical Center, 80 East Concord Street, Boston, MA 02118, USA.
| | - Gary B Kaplan
- Department of Psychiatry, Boston University School of Medicine, 720 Harrison Avenue, Boston, MA, 02118, USA; Mental Health Service, VA Boston Healthcare System, 940 Belmont Street, Brockton, MA, 02301, USA; Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, 72 East Concord Street, Boston, MA, 02118, USA.
| |
Collapse
|
17
|
Arriagada-Diaz J, Prado-Vega L, Cárdenas Díaz AM, Ardiles AO, Gonzalez-Jamett AM. Dynamin Superfamily at Pre- and Postsynapses: Master Regulators of Synaptic Transmission and Plasticity in Health and Disease. Neuroscientist 2020; 28:41-58. [PMID: 33300419 DOI: 10.1177/1073858420974313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Dynamin superfamily proteins (DSPs) comprise a large group of GTP-ases that orchestrate membrane fusion and fission, and cytoskeleton remodeling in different cell-types. At the central nervous system, they regulate synaptic vesicle recycling and signaling-receptor turnover, allowing the maintenance of synaptic transmission. In the presynapses, these GTP-ases control the recycling of synaptic vesicles influencing the size of the ready-releasable pool and the release of neurotransmitters from nerve terminals, whereas in the postsynapses, they are involved in AMPA-receptor trafficking to and from postsynaptic densities, supporting excitatory synaptic plasticity, and consequently learning and memory formation. In agreement with these relevant roles, an important number of neurological disorders are associated with mutations and/or dysfunction of these GTP-ases. Along the present review we discuss the importance of DSPs at synapses and their implication in different neuropathological contexts.
Collapse
Affiliation(s)
- Jorge Arriagada-Diaz
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile.,Programa de Magister en Ciencias, mención Neurociencia, Universidad de Valparaíso, Valparaíso, Chile
| | - Lorena Prado-Vega
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile.,Programa de Magister en Ciencias, mención Neurociencia, Universidad de Valparaíso, Valparaíso, Chile
| | - Ana M Cárdenas Díaz
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile
| | - Alvaro O Ardiles
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile.,Centro de Neurología Traslacional, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Centro Interdisciplinario de Estudios en Salud, Facultad de Medicina, Universidad de Valparaíso, Viña del Mar, Chile
| | - Arlek M Gonzalez-Jamett
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile
| |
Collapse
|
18
|
Mersman B, Zaidi W, Syed NI, Xu F. Taurine Promotes Neurite Outgrowth and Synapse Development of Both Vertebrate and Invertebrate Central Neurons. Front Synaptic Neurosci 2020; 12:29. [PMID: 32792935 PMCID: PMC7387692 DOI: 10.3389/fnsyn.2020.00029] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/24/2020] [Indexed: 12/13/2022] Open
Abstract
Taurine is a sulfur-containing amino acid that is widely expressed throughout the human brain, heart, retina, and muscle tissues. Taurine deficiency is associated with cardiomyopathy, renal dysfunction, abnormalities of the developing nervous system, and epilepsy which suggests a role specific to excitable tissues. Like vertebrates, invertebrates maintain high levels of taurine during embryonic and larval development, which decline during aging, indicating a potential developmental role. Notwithstanding its extensive presence throughout, taurine’s precise role/s during early brain development, function, and repair remains largely unknown in both vertebrate and invertebrate. Here, we investigated whether taurine affects neurite outgrowth, synapse formation, and synaptic transmission between postnatal day 0 rat cortical neurons in vitro, whereas its synaptogenic role was tested more directly using the Lymnaea soma-soma synapse model. We provide direct evidence that when applied at physiological concentrations, taurine exerts a significant neurotrophic effect on neuritic outgrowth and thickness of neurites as well as the expression of synaptic puncta as revealed by immunostaining of presynaptic synaptophysin and postsynaptic PSD95 proteins in rat cortical neurons, indicating direct involvement in synapse development. To demonstrate taurine’s direct effects on neurons in the absence of glia and other confounding factors, we next exploited individually identified pre- and postsynaptic neurons from the mollusk Lymnaea stagnalis. We found that taurine increased both the incidence of synapse formation (percent of cells that form synapses) and the efficacy of synaptic transmission between the paired neurons. This effect was comparable, but not additive, to Lymnaea trophic factor-induced synaptogenesis. This study thus provides direct morphological and functional evidence that taurine plays an important role in neurite outgrowth, synaptogenesis, and synaptic transmission during the early stages of brain development and that this role is conserved across both vertebrate and invertebrate species.
Collapse
Affiliation(s)
- Brittany Mersman
- Department of Biology, College of Arts and Sciences, Saint Louis University, St. Louis, MO, United States.,Henry and Amelia Nasrallah Center for Neuroscience, Saint Louis University, St. Louis, MO, United States
| | - Wali Zaidi
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Naweed I Syed
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Fenglian Xu
- Department of Biology, College of Arts and Sciences, Saint Louis University, St. Louis, MO, United States.,Henry and Amelia Nasrallah Center for Neuroscience, Saint Louis University, St. Louis, MO, United States
| |
Collapse
|
19
|
Capogna M, Castillo PE, Maffei A. The ins and outs of inhibitory synaptic plasticity: Neuron types, molecular mechanisms and functional roles. Eur J Neurosci 2020; 54:6882-6901. [PMID: 32663353 DOI: 10.1111/ejn.14907] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/30/2020] [Accepted: 07/08/2020] [Indexed: 01/05/2023]
Abstract
GABAergic interneurons are highly diverse, and their synaptic outputs express various forms of plasticity. Compelling evidence indicates that activity-dependent changes of inhibitory synaptic transmission play a significant role in regulating neural circuits critically involved in learning and memory and circuit refinement. Here, we provide an updated overview of inhibitory synaptic plasticity with a focus on the hippocampus and neocortex. To illustrate the diversity of inhibitory interneurons, we discuss the case of two highly divergent interneuron types, parvalbumin-expressing basket cells and neurogliaform cells, which support unique roles on circuit dynamics. We also present recent progress on the molecular mechanisms underlying long-term, activity-dependent plasticity of fast inhibitory transmission. Lastly, we discuss the role of inhibitory synaptic plasticity in neuronal circuits' function. The emerging picture is that inhibitory synaptic transmission in the CNS is extremely diverse, undergoes various mechanistically distinct forms of plasticity and contributes to a much more refined computational role than initially thought. Both the remarkable diversity of inhibitory interneurons and the various forms of plasticity expressed by GABAergic synapses provide an amazingly rich inhibitory repertoire that is central to a variety of complex neural circuit functions, including memory.
Collapse
Affiliation(s)
- Marco Capogna
- Department of Biomedicine, Danish National Research Foundation Center of Excellence PROMEMO, Aarhus University, Aarhus, Denmark
| | - Pablo E Castillo
- Dominck P Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA.,Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Arianna Maffei
- Center for Neural Circuit Dynamics and Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, NY, USA
| |
Collapse
|
20
|
Cejnar P, Vyšata O, Kukal J, Beránek M, Vališ M, Procházka A. Simple capacitor-switch model of excitatory and inhibitory neuron with all parts biologically explained allows input fire pattern dependent chaotic oscillations. Sci Rep 2020; 10:7353. [PMID: 32355185 PMCID: PMC7192907 DOI: 10.1038/s41598-020-63834-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Accepted: 04/03/2020] [Indexed: 11/09/2022] Open
Abstract
Due to known information processing capabilities of the brain, neurons are modeled at many different levels. Circuit theory is also often used to describe the function of neurons, especially in complex multi-compartment models, but when used for simple models, there is no subsequent biological justification of used parts. We propose a new single-compartment model of excitatory and inhibitory neuron, the capacitor-switch model of excitatory and inhibitory neuron, as an extension of the existing integrate-and-fire model, preserving the signal properties of more complex multi-compartment models. The correspondence to existing structures in the neuronal cell is then discussed for each part of the model. We demonstrate that a few such inter-connected model units are capable of acting as a chaotic oscillator dependent on fire patterns of the input signal providing a complex deterministic and specific response through the output signal. The well-known necessary conditions for constructing a chaotic oscillator are met for our presented model. The capacitor-switch model provides a biologically-plausible concept of chaotic oscillator based on neuronal cells.
Collapse
Affiliation(s)
- Pavel Cejnar
- Department of Computing and Control Engineering, Faculty of Chemical Engineering, University of Chemistry and Technology in Prague, Prague, Czech Republic.
| | - Oldřich Vyšata
- Department of Computing and Control Engineering, Faculty of Chemical Engineering, University of Chemistry and Technology in Prague, Prague, Czech Republic
- Department of Neurology, Faculty of Medicine in Hradec Králové, Charles University, Hradec Králové, Czech Republic
| | - Jaromír Kukal
- Department of Computing and Control Engineering, Faculty of Chemical Engineering, University of Chemistry and Technology in Prague, Prague, Czech Republic
| | | | - Martin Vališ
- Department of Neurology, Faculty of Medicine in Hradec Králové, Charles University, Hradec Králové, Czech Republic
| | - Aleš Procházka
- Department of Computing and Control Engineering, Faculty of Chemical Engineering, University of Chemistry and Technology in Prague, Prague, Czech Republic.
- Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Prague, Czech Republic.
| |
Collapse
|
21
|
Kim SY, Lim W. Effect of interpopulation spike-timing-dependent plasticity on synchronized rhythms in neuronal networks with inhibitory and excitatory populations. Cogn Neurodyn 2020; 14:535-567. [PMID: 32655716 DOI: 10.1007/s11571-020-09580-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/11/2020] [Accepted: 03/06/2020] [Indexed: 02/07/2023] Open
Abstract
We consider a two-population network consisting of both inhibitory (I) interneurons and excitatory (E) pyramidal cells. This I-E neuronal network has adaptive dynamic I to E and E to I interpopulation synaptic strengths, governed by interpopulation spike-timing-dependent plasticity (STDP). In previous works without STDPs, fast sparsely synchronized rhythms, related to diverse cognitive functions, were found to appear in a range of noise intensity D for static synaptic strengths. Here, by varying D, we investigate the effect of interpopulation STDPs on fast sparsely synchronized rhythms that emerge in both the I- and the E-populations. Depending on values of D, long-term potentiation (LTP) and long-term depression (LTD) for population-averaged values of saturated interpopulation synaptic strengths are found to occur. Then, the degree of fast sparse synchronization varies due to effects of LTP and LTD. In a broad region of intermediate D, the degree of good synchronization (with higher synchronization degree) becomes decreased, while in a region of large D, the degree of bad synchronization (with lower synchronization degree) gets increased. Consequently, in each I- or E-population, the synchronization degree becomes nearly the same in a wide range of D (including both the intermediate and the large D regions). This kind of "equalization effect" is found to occur via cooperative interplay between the average occupation and pacing degrees of spikes (i.e., the average fraction of firing neurons and the average degree of phase coherence between spikes in each synchronized stripe of spikes in the raster plot of spikes) in fast sparsely synchronized rhythms. Finally, emergences of LTP and LTD of interpopulation synaptic strengths (leading to occurrence of equalization effect) are intensively investigated via a microscopic method based on the distributions of time delays between the pre- and the post-synaptic spike times.
Collapse
Affiliation(s)
- Sang-Yoon Kim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu, 42411 Korea
| | - Woochang Lim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu, 42411 Korea
| |
Collapse
|
22
|
Gandolfi D, Bigiani A, Porro CA, Mapelli J. Inhibitory Plasticity: From Molecules to Computation and Beyond. Int J Mol Sci 2020; 21:ijms21051805. [PMID: 32155701 PMCID: PMC7084224 DOI: 10.3390/ijms21051805] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 02/28/2020] [Accepted: 03/03/2020] [Indexed: 11/17/2022] Open
Abstract
Synaptic plasticity is the cellular and molecular counterpart of learning and memory and, since its first discovery, the analysis of the mechanisms underlying long-term changes of synaptic strength has been almost exclusively focused on excitatory connections. Conversely, inhibition was considered as a fixed controller of circuit excitability. Only recently, inhibitory networks were shown to be finely regulated by a wide number of mechanisms residing in their synaptic connections. Here, we review recent findings on the forms of inhibitory plasticity (IP) that have been discovered and characterized in different brain areas. In particular, we focus our attention on the molecular pathways involved in the induction and expression mechanisms leading to changes in synaptic efficacy, and we discuss, from the computational perspective, how IP can contribute to the emergence of functional properties of brain circuits.
Collapse
Affiliation(s)
- Daniela Gandolfi
- Department of Biomedical, Metabolic and Neural Sciences and Center for Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena, Italy; (D.G.); (A.B.); (C.A.P.)
- Department of Brain and behavioral sciences, University of Pavia, 27100 Pavia, Italy
| | - Albertino Bigiani
- Department of Biomedical, Metabolic and Neural Sciences and Center for Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena, Italy; (D.G.); (A.B.); (C.A.P.)
| | - Carlo Adolfo Porro
- Department of Biomedical, Metabolic and Neural Sciences and Center for Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena, Italy; (D.G.); (A.B.); (C.A.P.)
| | - Jonathan Mapelli
- Department of Biomedical, Metabolic and Neural Sciences and Center for Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena, Italy; (D.G.); (A.B.); (C.A.P.)
- Correspondence: ; Tel.: +39-059-205- 5459
| |
Collapse
|
23
|
Morales-Weil K, Moreno M, Ahumada J, Arriagada J, Fuentealba P, Bonansco C, Fuenzalida M. Priming of GABAergic Long-term Potentiation by Muscarinic Receptors. Neuroscience 2020; 428:242-251. [PMID: 31917346 DOI: 10.1016/j.neuroscience.2019.12.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 11/25/2019] [Accepted: 12/19/2019] [Indexed: 12/28/2022]
Abstract
Growing evidence indicates that GABAergic interneurons play a pivotal role to generate brain oscillation patterns, which are fundamental for the mnemonic processing of the hippocampus. While acetylcholine (ACh) is a powerful modulator of synaptic plasticity and brain function, few studies have been focused on the role of cholinergic signaling in the regulation of GABAergic inhibitory synaptic plasticity. We have previously shown that co-activation of endocannabinoids (CB1R) and muscarinic receptor (mAChR) in hippocampal interneurons can induce activity-dependent GABAergic long-term depression in CA1 pyramidal neurons. Here, using electrophysiological and pharmacological approaches in acute rat hippocampal slices, we show that activation of cholinergic receptors followed by either high-frequency stimulation of Schaeffer collaterals or exogenous activation of metabotropic glutamate receptor (mGluR) induces a robust long-term potentiation at GABAergic synapses (iLTP). These forms of iLTP are blocked by the M1 type of mAChR (MR1) or by the group I of mGluR (mGluR1/5) antagonists. These results suggest the existence of spatiotemporal cooperativity between cholinergic and glutamatergic pathways where activation of mAChR serves as a metaplastic switch making glutamatergic synapses capable to induce long-term potentiation at inhibitory synapses, that may contribute to the modulation of brain mechanisms of learning and memory.
Collapse
Affiliation(s)
- Koyam Morales-Weil
- Centro de Neurobiología y Fisiopatología Integrativa, Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Chile; Programa de Doctorado en Ciencias, mención Neurociencias, Universidad de Valparaíso, Chile
| | - Macarena Moreno
- Centro interdisciplinario de Neurociencias, Pontificia Universidad Católica de Chile, Chile
| | - Juan Ahumada
- Centro de Neurobiología y Fisiopatología Integrativa, Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Chile; Programa de Doctorado en Ciencias, mención Neurociencias, Universidad de Valparaíso, Chile
| | - Jorge Arriagada
- Centro de Neurobiología y Fisiopatología Integrativa, Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Chile
| | - Pablo Fuentealba
- Departamento de Psiquiatría, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Chile
| | - Christian Bonansco
- Centro de Neurobiología y Fisiopatología Integrativa, Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Chile
| | - Marco Fuenzalida
- Centro de Neurobiología y Fisiopatología Integrativa, Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Chile.
| |
Collapse
|
24
|
Park SM, Hwang HG, Woo JU, Lee WH, Chae SJ, Nahm S. Improvement of Conductance Modulation Linearity in a Cu 2+-Doped KNbO 3 Memristor through the Increase of the Number of Oxygen Vacancies. ACS APPLIED MATERIALS & INTERFACES 2020; 12:1069-1077. [PMID: 31820625 DOI: 10.1021/acsami.9b18794] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The Pt/KNbO3/TiN/Si (KN) memristor exhibits various biological synaptic properties. However, it also displays nonlinear conductance modulation with the application of identical pulses, indicating that it should be improved for neuromorphic applications. The abrupt change of the conductance originates from the inhomogeneous growth/dissolution of oxygen vacancy filaments in the KN film. The change of the filaments in a KN film is controlled by two mechanisms with different growth/dissolution rates: a redox process with a fast rate and an oxygen vacancy diffusion process with a slow rate. Therefore, the conductance modulation linearity can be improved if the growth/dissolution of the filaments is controlled by only one mechanism. When the number of oxygen vacancies in the KN film was increased through doping of Cu2+ ions, the growth/dissolution of the filaments in the Cu2+-doped KN (CKN) film was mainly influenced by the redox process of oxygen vacancies. Therefore, the CKN film exhibited improved conductance modulation linearity, confirming that the linearity of conductance modulation can be improved by increasing the number of oxygen vacancies in the memristor. This method can be applied to other memristors to improve the linearity of conductance modulation. The CKN memristor also provides excellent biological synaptic characteristics for neuromorphic computing systems.
Collapse
|
25
|
Wolpaw JR, Millán JDR, Ramsey NF. Brain-computer interfaces: Definitions and principles. HANDBOOK OF CLINICAL NEUROLOGY 2020; 168:15-23. [PMID: 32164849 DOI: 10.1016/b978-0-444-63934-9.00002-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Throughout life, the central nervous system (CNS) interacts with the world and with the body by activating muscles and excreting hormones. In contrast, brain-computer interfaces (BCIs) quantify CNS activity and translate it into new artificial outputs that replace, restore, enhance, supplement, or improve the natural CNS outputs. BCIs thereby modify the interactions between the CNS and the environment. Unlike the natural CNS outputs that come from spinal and brainstem motoneurons, BCI outputs come from brain signals that represent activity in other CNS areas, such as the sensorimotor cortex. If BCIs are to be useful for important communication and control tasks in real life, the CNS must control these brain signals nearly as reliably and accurately as it controls spinal motoneurons. To do this, they might, for example, need to incorporate software that mimics the function of the subcortical and spinal mechanisms that participate in normal movement control. The realization of high reliability and accuracy is perhaps the most difficult and critical challenge now facing BCI research and development. The ongoing adaptive modifications that maintain effective natural CNS outputs take place primarily in the CNS. The adaptive modifications that maintain effective BCI outputs can also take place in the BCI. This means that the BCI operation depends on the effective collaboration of two adaptive controllers, the CNS and the BCI. Realization of this second adaptive controller, the BCI, and management of its interactions with concurrent adaptations in the CNS comprise another complex and critical challenge for BCI development. BCIs can use different kinds of brain signals recorded in different ways from different brain areas. Decisions about which signals recorded in which ways from which brain areas should be selected for which applications are empirical questions that can only be properly answered by experiments. BCIs, like other communication and control technologies, often face artifacts that contaminate or imitate their chosen signals. Noninvasive BCIs (e.g., EEG- or fNIRS-based) need to take special care to avoid interpreting nonbrain signals (e.g., cranial EMG) as brain signals. This typically requires comprehensive topographical and spectral evaluations. In theory, the outputs of BCIs can select a goal or control a process. In the future, the most effective BCIs will probably be those that combine goal selection and process control so as to distribute control between the BCI and the application in a fashion suited to the current action. Through such distribution, BCIs may most effectively imitate natural CNS operation. The primary measure of BCI development is the extent to which BCI systems benefit people with neuromuscular disorders. Thus, BCI clinical evaluation, validation, and dissemination is a key step. It is at the same time a complex and difficult process that depends on multidisciplinary collaboration and management of the demanding requirements of clinical studies. Twenty-five years ago, BCI research was an esoteric endeavor pursued in only a few isolated laboratories. It is now a steadily growing field that engages many hundreds of scientists, engineers, and clinicians throughout the world in an increasingly interconnected community that is addressing the key issues and pursuing the high potential of BCI technology.
Collapse
Affiliation(s)
- Jonathan R Wolpaw
- National Center for Adaptive Neurotechnologies and Stratton VA Medical Center, Wadsworth Center, Albany, NY, United States
| | - José Del R Millán
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, United States; Department of Neurology, The University of Texas at Austin, Austin, TX, United States
| | - Nick F Ramsey
- Brain Center, University Medical Center Utrecht, Utrecht, The Netherlands
| |
Collapse
|
26
|
Kobayashi S, Kim J, Yanagawa Y, Suzuki N, Saito H, Takayama C. Hyper-Formation of GABA and Glycine Co-Releasing Terminals in the Mouse Cerebellar Nuclei after Deprivation of GABAergic Inputs from Purkinje Cells. Neuroscience 2019; 426:88-100. [PMID: 31846755 DOI: 10.1016/j.neuroscience.2019.11.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 11/11/2019] [Accepted: 11/19/2019] [Indexed: 11/27/2022]
Abstract
GABA and glycine are inhibitory neurotransmitters. However, the mechanisms underlying the formation of GABAergic and glycinergic synapses remain unclear. The influence of GABAergic input deprivation on inhibitory terminal formation was investigated using Purkinje cell (PC)-specific vesicular GABA transporter (VGAT) knockout (L7-VGAT) mice, in which GABA release from PCs diminishes in an age-dependent manner. We compared the late development of GABAergic and glycinergic terminals in the cerebellar nucleus (CN) between control and L7-VGAT mice. In the control CN, the density of glutamate decarboxylase (GAD)-positive dots remained unchanged between postnatal 2 months (P2M) and 13 months (P13M), whereas glycine transporter 2 (GlyT2)-positive dots increased in density during this time frame. No difference in the density of GlyT2-positive dots was observed between control and L7-VGAT mice at P2M, but the density was significantly higher in the L7-VGAT fastigial nuclei (FN) than the control FN at P13M. When VGAT was absent from PC terminals, GlyT2-positive dots included GAD and VGAT and formed synapses. These results indicated that GABAergic terminals were formed by P2M, glycinergic terminals were actively formed after P2M, and more glycinergic terminals were formed in the L7-VGAT FN than in the control FN, suggesting that the increased glycinergic terminals may derive from interneurons within the FN and may also release GABA. These results suggest that the deprivation of GABAergic inputs from PCs may accelerate the formation of co-releasing terminals derived from interneurons and that the inhibitory terminal numbers and types may be regulated by the quantity of functional GABAergic inputs.
Collapse
Affiliation(s)
- Shiori Kobayashi
- Department of Molecular Anatomy, School of Medicine, University of the Ryukyus, Uehara 207, Nishihara, Okinawa 9030215, Japan
| | - Jeongtae Kim
- Department of Molecular Anatomy, School of Medicine, University of the Ryukyus, Uehara 207, Nishihara, Okinawa 9030215, Japan; Department of Veterinary Anatomy, College of Veterinary Medicine and Veterinary Medical Research Institute, Jeju National University, Jeju 63243, Republic of Korea
| | - Yuchio Yanagawa
- Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine, 3-39-22 Showa-Machi, Maebashi, Gunma 371-8511, Japan
| | - Noboru Suzuki
- Department of Animal Functional Genomics of Advanced Science Research Promotion Center, Mie University Organization for the Promotion of Regional Innovation, 2-174 Edobashi, Tsu, Mie 5148507, Japan
| | - Hiromitsu Saito
- Department of Animal Functional Genomics of Advanced Science Research Promotion Center, Mie University Organization for the Promotion of Regional Innovation, 2-174 Edobashi, Tsu, Mie 5148507, Japan
| | - Chitoshi Takayama
- Department of Molecular Anatomy, School of Medicine, University of the Ryukyus, Uehara 207, Nishihara, Okinawa 9030215, Japan.
| |
Collapse
|
27
|
Ghafouri S, Fathollahi Y, Semnanian S, Shojaei A, Asgari A, Ebrahim Amini A, Mirnajafi-Zadeh J. Deep brain stimulation restores the glutamatergic and GABAergic synaptic transmission and plasticity to normal levels in kindled rats. PLoS One 2019; 14:e0224834. [PMID: 31697763 PMCID: PMC6837391 DOI: 10.1371/journal.pone.0224834] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Accepted: 10/22/2019] [Indexed: 01/13/2023] Open
Abstract
Background The precise effect of low frequency stimulation (LFS) as a newly postulated, anticonvulsant therapeutic approach on seizure-induced changes in synaptic transmission has not been completely determined. Hypothesis In this study, the LFS effect on impaired, synaptic plasticity in kindled rats was investigated. Methods Hippocampal kindled rats received LFS (4 trials consisting of one train of 200 monophasic square waves, 0.1 ms pulse duration, 1 Hz) on four occasions. LTP induction was evaluated using whole-cell recordings of evoked excitatory and inhibitory post-synaptic potentials (EPSPs and IPSPs respectively) in CA1 neurons in hippocampal slices. In addition, the hippocampal excitatory and inhibitory post-synaptic currents (EPSCs and IPSCs), and the gene expression of NR2A, GluR2 and γ2 were evaluated. Results LTP induction was attenuated in excitatory and inhibitory synapses in hippocampal slices of kindled rats. When LFS was applied in kindled animals, LTP was induced in EPSPs and IPSPs. Moreover, LFS increased and decreased the threshold intensities of EPSCs and IPSCs respectively. In kindled animals, NR2A gene expression increased, while γ2 gene expression decreased. GluR2 gene expression did not significantly change. Applying LFS in kindled animals mitigated these changes: No significant differences were observed in NR2A, γ2 and GluR2 gene expression in the kindled+LFS and control groups. Conclusion The application of LFS in kindled animals restored LTP induction in both EPSPs and IPSPs, and returned the threshold intensity for induction of EPSCs, IPSCs and gene expression to similar levels as controls.
Collapse
Affiliation(s)
- Samireh Ghafouri
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Yaghoub Fathollahi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Saeed Semnanian
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Amir Shojaei
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Azam Asgari
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
- Département de Neurosciences, Université de Montréal, Montréal, Canada
| | - Azin Ebrahim Amini
- Department of Biomaterial and Biomedical Engineering (IBBME), Faculty of applied sciences, University of Toronto, Toronto, Canada
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
- Institute for Brain Sciences and Cognition, Tarbiat Modares University, Tehran, Iran
- * E-mail:
| |
Collapse
|
28
|
Huang YC, Pirri JK, Rayes D, Gao S, Mulcahy B, Grant J, Saheki Y, Francis MM, Zhen M, Alkema MJ. Gain-of-function mutations in the UNC-2/CaV2α channel lead to excitation-dominant synaptic transmission in Caenorhabditis elegans. eLife 2019; 8:e45905. [PMID: 31364988 PMCID: PMC6713474 DOI: 10.7554/elife.45905] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 07/30/2019] [Indexed: 01/17/2023] Open
Abstract
Mutations in pre-synaptic voltage-gated calcium channels can lead to familial hemiplegic migraine type 1 (FHM1). While mammalian studies indicate that the migraine brain is hyperexcitable due to enhanced excitation or reduced inhibition, the molecular and cellular mechanisms underlying this excitatory/inhibitory (E/I) imbalance are poorly understood. We identified a gain-of-function (gf) mutation in the Caenorhabditis elegans CaV2 channel α1 subunit, UNC-2, which leads to increased calcium currents. unc-2(zf35gf) mutants exhibit hyperactivity and seizure-like motor behaviors. Expression of the unc-2 gene with FHM1 substitutions R192Q and S218L leads to hyperactivity similar to that of unc-2(zf35gf) mutants. unc-2(zf35gf) mutants display increased cholinergic and decreased GABAergic transmission. Moreover, increased cholinergic transmission in unc-2(zf35gf) mutants leads to an increase of cholinergic synapses and a TAX-6/calcineurin-dependent reduction of GABA synapses. Our studies reveal mechanisms through which CaV2 gain-of-function mutations disrupt excitation-inhibition balance in the nervous system.
Collapse
Affiliation(s)
- Yung-Chi Huang
- Department of NeurobiologyUniversity of Massachusetts Medical SchoolWorcesterUnited States
| | - Jennifer K Pirri
- Department of NeurobiologyUniversity of Massachusetts Medical SchoolWorcesterUnited States
| | - Diego Rayes
- Department of NeurobiologyUniversity of Massachusetts Medical SchoolWorcesterUnited States
| | - Shangbang Gao
- Lunenfeld-Tanenbaum Research InstituteMount Sinai HospitalTorontoCanada
| | - Ben Mulcahy
- Lunenfeld-Tanenbaum Research InstituteMount Sinai HospitalTorontoCanada
| | - Jeff Grant
- Department of NeurobiologyUniversity of Massachusetts Medical SchoolWorcesterUnited States
| | - Yasunori Saheki
- Lulu and Anthony Wang Laboratory of Neural Circuits and BehaviorThe Rockefeller UniversityNew YorkUnited States
| | - Michael M Francis
- Department of NeurobiologyUniversity of Massachusetts Medical SchoolWorcesterUnited States
| | - Mei Zhen
- Lunenfeld-Tanenbaum Research InstituteMount Sinai HospitalTorontoCanada
- Department of Molecular GeneticsUniversity of TorontoTorontoCanada
- Department of PhysiologyUniversity of TorontoTorontoCanada
| | - Mark J Alkema
- Department of NeurobiologyUniversity of Massachusetts Medical SchoolWorcesterUnited States
| |
Collapse
|
29
|
Torres-Costa V, Mäkilä E, Granroth S, Kukk E, Salonen J. Synaptic and Fast Switching Memristance in Porous Silicon-Based Structures. NANOMATERIALS 2019; 9:nano9060825. [PMID: 31159254 PMCID: PMC6631600 DOI: 10.3390/nano9060825] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 05/27/2019] [Accepted: 05/28/2019] [Indexed: 11/16/2022]
Abstract
Memristors are two terminal electronic components whose conductance depends on the amount of charge that has flown across them over time. This dependence can be gradual, such as in synaptic memristors, or abrupt, as in resistive switching memristors. Either of these memory effects are very promising for the development of a whole new generation of electronic devices. For the successful implementation of practical memristors, however, the development of low cost industry compatible memristive materials is required. Here the memristive properties of differently processed porous silicon structures are presented, which are suitable for different applications. Electrical characterization and SPICE simulations show that laser-carbonized porous silicon shows a strong synaptic memristive behavior influenced by defect diffusion, while wet-oxidized porous silicon has strong resistance switching properties, with switching ratios over 8000. Results show that practical memristors of either type can be achieved with porous silicon whose memristive properties can be adjusted by the proper material processing. Thus, porous silicon may play an important role for the successful realization of practical memristorics with cost-effective materials and processes.
Collapse
Affiliation(s)
- Vicente Torres-Costa
- Deptartamento de Física Aplicada and Centro de Micro-Análisis de Materiales, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
| | - Ermei Mäkilä
- Department of Physics and Astronomy, University of Turku, FI-20014 Turku, Finland.
| | - Sari Granroth
- Department of Physics and Astronomy, University of Turku, FI-20014 Turku, Finland.
| | - Edwin Kukk
- Department of Physics and Astronomy, University of Turku, FI-20014 Turku, Finland.
| | - Jarno Salonen
- Department of Physics and Astronomy, University of Turku, FI-20014 Turku, Finland.
| |
Collapse
|
30
|
Carroll J, Warren A, Täuber UC. Effects of inhibitory and excitatory neurons on the dynamics and control of avalanching neural networks. Phys Rev E 2019; 99:052407. [PMID: 31212542 DOI: 10.1103/physreve.99.052407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Indexed: 06/09/2023]
Abstract
The statistical analysis of the collective neural activity known as avalanches provides insight into the proper behavior of brains across many species. We consider a neural network model based on the work of Lombardi, Herrmann, De Arcangelis et al. that captures the relevant dynamics of neural avalanches, and we show how tuning the fraction of inhibitory neurons in this model alters the connectivity of the network over time, removes exponential cut-offs present in the distributions of avalanche size and duration, and transitions the power spectral density of the network into an "epileptic" regime. We propose that the brain operates away from this power-law regime of low inhibitory fraction to protect itself from the dominating avalanches present in these extended distributions. We present control strategies that curtail these power-law distributions through either random or, more effectively, targeted disabling of excitatory neurons.
Collapse
Affiliation(s)
- Jacob Carroll
- Department of Physics (MC 0435) and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - Ada Warren
- Department of Physics (MC 0435) and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - Uwe C Täuber
- Department of Physics (MC 0435) and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| |
Collapse
|
31
|
Lah MHC, Reza F, Begum T, Abdullah JM. Role of Pre-Synaptic NMDA Receptors in the Modulation of Inhibitory Synaptic Transmission in Sensory-Motor and Visual Cortical Pyramidal Neurons in Brain Slices of Young Epileptic Mice. Malays J Med Sci 2019; 25:27-39. [PMID: 30899185 PMCID: PMC6422549 DOI: 10.21315/mjms2018.25.3.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 04/24/2018] [Indexed: 10/28/2022] Open
Abstract
Background Previous studies from animal models have shown that pre-synaptic NMDA receptors (preNMDARs) are present in the cortex, but the role of inhibition mediated by preNMDARs during epileptogenesis remains unclear. In this study, we wanted to observe the changes in GABAergic inhibition through preNMDARs in sensory-motor and visual cortical pyramidal neurons after pilocarpine-induced status epilepticus. Methods Using a pilocarpine-induced epileptic mouse model, sensory-motor and visual cortical slices were prepared, and the whole-cell patch clamp technique was used to record spontaneous inhibitory post-synaptic currents (sIPSCs). Results The primary finding was that the mean amplitude of sIPSC from the sensory-motor cortex increased significantly in epileptic mice when the recording pipette contained MK-801 compared to control mice, whereas the mean sIPSC frequency was not significantly different, indicating that post-synaptic mechanisms are involved. However, there was no significant pre-synaptic inhibition through preNMDARs in the acute brain slices from pilocarpine-induced epileptic mice. Conclusion In the acute case of epilepsy, a compensatory mechanism of post-synaptic inhibition, possibly from ambient GABA, was observed through changes in the amplitude without significant changes in the frequency of sIPSC compared to control mice. The role of preNMDAR-mediated inhibition in epileptogenesis during the chronic condition or in the juvenile stage warrants further investigation.
Collapse
Affiliation(s)
- Muhammad Hanif Che Lah
- Department of Neurosciences, School of Medical Sciences, Universiti Sains, Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| | - Faruque Reza
- Department of Neurosciences, School of Medical Sciences, Universiti Sains, Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| | - Tahamina Begum
- Department of Neurosciences, School of Medical Sciences, Universiti Sains, Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| | - Jafri Malin Abdullah
- Department of Neurosciences, School of Medical Sciences, Universiti Sains, Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia.,Center for Neuroscience Services and Research (P3Neuro), Universiti Sains, Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| |
Collapse
|
32
|
Salmasi M, Loebel A, Glasauer S, Stemmler M. Short-term synaptic depression can increase the rate of information transfer at a release site. PLoS Comput Biol 2019; 15:e1006666. [PMID: 30601804 PMCID: PMC6355030 DOI: 10.1371/journal.pcbi.1006666] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 01/31/2019] [Accepted: 11/23/2018] [Indexed: 11/18/2022] Open
Abstract
The release of neurotransmitters from synapses obeys complex and stochastic dynamics. Depending on the recent history of synaptic activation, many synapses depress the probability of releasing more neurotransmitter, which is known as synaptic depression. Our understanding of how synaptic depression affects the information efficacy, however, is limited. Here we propose a mathematically tractable model of both synchronous spike-evoked release and asynchronous release that permits us to quantify the information conveyed by a synapse. The model transits between discrete states of a communication channel, with the present state depending on many past time steps, emulating the gradual depression and exponential recovery of the synapse. Asynchronous and spontaneous releases play a critical role in shaping the information efficacy of the synapse. We prove that depression can enhance both the information rate and the information rate per unit energy expended, provided that synchronous spike-evoked release depresses less (or recovers faster) than asynchronous release. Furthermore, we explore the theoretical implications of short-term synaptic depression adapting on longer time scales, as part of the phenomenon of metaplasticity. In particular, we show that a synapse can adjust its energy expenditure by changing the dynamics of short-term synaptic depression without affecting the net information conveyed by each successful release. Moreover, the optimal input spike rate is independent of the amplitude or time constant of synaptic depression. We analyze the information efficacy of three types of synapses for which the short-term dynamics of both synchronous and asynchronous release have been experimentally measured. In hippocampal autaptic synapses, the persistence of asynchronous release during depression cannot compensate for the reduction of synchronous release, so that the rate of information transmission declines with synaptic depression. In the calyx of Held, the information rate per release remains constant despite large variations in the measured asynchronous release rate. Lastly, we show that dopamine, by controlling asynchronous release in corticostriatal synapses, increases the synaptic information efficacy in nucleus accumbens. Fatigue is an intrinsic property of living systems and synapses are no exception. Synaptic depression reduces the ability of synapses to release vesicles in response to an incoming action potential. Whether synaptic depression simply reflects the exhaustion of neuronal resources or whether it serves some additional function is still an open question. We ask how synaptic depression modulates the information transfer between neurons by keeping the synapse in an appropriate operating range. Using a tractable mathematical model for synaptic depression of both synchronous spike-evoked and asynchronous release of neurotransmitter, we derive a closed-form expression for the mutual information rate. Depression, it turns out, can both enhance or impair information transfer, depending on the relative level of depression for synchronous spike-evoked and asynchronous releases. We also study the compromise a synapse makes between its energy consumption and the rate of information transmission. Interestingly, we show that synaptic depression can regulate energy use without affecting the information (measured in bits) per synaptic release. By applying our mathematical framework to experimentally measured synapses, we show that some synapses can compensate for intrinsic variability in asynchronous release rates; moreover, we show how neuromodulators such as dopamine act to improve the information transmission rate.
Collapse
Affiliation(s)
- Mehrdad Salmasi
- Graduate School of Systemic Neurosciences, Ludwig-Maximilians-Universität, Munich, Germany.,Bernstein Center for Computational Neuroscience, Munich, Germany.,German Center for Vertigo and Balance Disorders, Ludwig-Maximilians-Universität, Munich, Germany
| | - Alex Loebel
- Bernstein Center for Computational Neuroscience, Munich, Germany.,Department of Biology II, Ludwig-Maximilians-Universität, Munich, Germany
| | - Stefan Glasauer
- Bernstein Center for Computational Neuroscience, Munich, Germany.,German Center for Vertigo and Balance Disorders, Ludwig-Maximilians-Universität, Munich, Germany.,Chair of Computational Neuroscience, Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
| | - Martin Stemmler
- Bernstein Center for Computational Neuroscience, Munich, Germany.,Department of Biology II, Ludwig-Maximilians-Universität, Munich, Germany
| |
Collapse
|
33
|
Mongillo G, Rumpel S, Loewenstein Y. Inhibitory connectivity defines the realm of excitatory plasticity. Nat Neurosci 2018; 21:1463-1470. [PMID: 30224809 DOI: 10.1038/s41593-018-0226-x] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 07/30/2018] [Indexed: 12/19/2022]
Abstract
Recent experiments demonstrate substantial volatility of excitatory connectivity in the absence of any learning. This challenges the hypothesis that stable synaptic connections are necessary for long-term maintenance of acquired information. Here we measure ongoing synaptic volatility and use theoretical modeling to study its consequences on cortical dynamics. We show that in the balanced cortex, patterns of neural activity are primarily determined by inhibitory connectivity, despite the fact that most synapses and neurons are excitatory. Similarly, we show that the inhibitory network is more effective in storing memory patterns than the excitatory one. As a result, network activity is robust to ongoing volatility of excitatory synapses, as long as this volatility does not disrupt the balance between excitation and inhibition. We thus hypothesize that inhibitory connectivity, rather than excitatory, controls the maintenance and loss of information over long periods of time in the volatile cortex.
Collapse
Affiliation(s)
- Gianluigi Mongillo
- Centre National de la Recherche Scientifique (CNRS), Paris, France. .,Centre de Neurophysique, Physiologie et Pathologie (CNPP), Université Descartes, Paris, France.
| | - Simon Rumpel
- Institute of Physiology, Focus Program Translational Neuroscience, University Medical Center, Johannes Gutenberg University, Mainz, Germany
| | - Yonatan Loewenstein
- Department of Neurobiology, the Federmann Center for the Study of Rationality and the Edmond and Lily Safra Center for Brain Sciences, The Hebrew University, Jerusalem, Israel.
| |
Collapse
|
34
|
Kim SY, Lim W. Burst synchronization in a scale-free neuronal network with inhibitory spike-timing-dependent plasticity. Cogn Neurodyn 2018; 13:53-73. [PMID: 30728871 DOI: 10.1007/s11571-018-9505-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/19/2018] [Accepted: 08/28/2018] [Indexed: 01/09/2023] Open
Abstract
We are concerned about burst synchronization (BS), related to neural information processes in health and disease, in the Barabási-Albert scale-free network (SFN) composed of inhibitory bursting Hindmarsh-Rose neurons. This inhibitory neuronal population has adaptive dynamic synaptic strengths governed by the inhibitory spike-timing-dependent plasticity (iSTDP). In previous works without considering iSTDP, BS was found to appear in a range of noise intensities for fixed synaptic inhibition strengths. In contrast, in our present work, we take into consideration iSTDP and investigate its effect on BS by varying the noise intensity. Our new main result is to find occurrence of a Matthew effect in inhibitory synaptic plasticity: good BS gets better via LTD, while bad BS get worse via LTP. This kind of Matthew effect in inhibitory synaptic plasticity is in contrast to that in excitatory synaptic plasticity where good (bad) synchronization gets better (worse) via LTP (LTD). We note that, due to inhibition, the roles of LTD and LTP in inhibitory synaptic plasticity are reversed in comparison with those in excitatory synaptic plasticity. Moreover, emergences of LTD and LTP of synaptic inhibition strengths are intensively investigated via a microscopic method based on the distributions of time delays between the pre- and the post-synaptic burst onset times. Finally, in the presence of iSTDP we investigate the effects of network architecture on BS by varying the symmetric attachment degree l ∗ and the asymmetry parameter Δ l in the SFN.
Collapse
Affiliation(s)
- Sang-Yoon Kim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu, 42411 Korea
| | - Woochang Lim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu, 42411 Korea
| |
Collapse
|
35
|
Kim SY, Lim W. Effect of inhibitory spike-timing-dependent plasticity on fast sparsely synchronized rhythms in a small-world neuronal network. Neural Netw 2018; 106:50-66. [PMID: 30025272 DOI: 10.1016/j.neunet.2018.06.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 05/14/2018] [Accepted: 06/25/2018] [Indexed: 02/06/2023]
Abstract
We consider the Watts-Strogatz small-world network (SWN) consisting of inhibitory fast spiking Izhikevich interneurons. This inhibitory neuronal population has adaptive dynamic synaptic strengths governed by the inhibitory spike-timing-dependent plasticity (iSTDP). In previous works without iSTDP, fast sparsely synchronized rhythms, associated with diverse cognitive functions, were found to appear in a range of large noise intensities for fixed strong synaptic inhibition strengths. Here, we investigate the effect of iSTDP on fast sparse synchronization (FSS) by varying the noise intensity D. We employ an asymmetric anti-Hebbian time window for the iSTDP update rule [which is in contrast to the Hebbian time window for the excitatory STDP (eSTDP)]. Depending on values of D, population-averaged values of saturated synaptic inhibition strengths are potentiated [long-term potentiation (LTP)] or depressed [long-term depression (LTD)] in comparison with the initial mean value, and dispersions from the mean values of LTP/LTD are much increased when compared with the initial dispersion, independently of D. In most cases of LTD where the effect of mean LTD is dominant in comparison with the effect of dispersion, good synchronization (with higher spiking measure) is found to get better via LTD, while bad synchronization (with lower spiking measure) is found to get worse via LTP. This kind of Matthew effect in inhibitory synaptic plasticity is in contrast to that in excitatory synaptic plasticity where good (bad) synchronization gets better (worse) via LTP (LTD). Emergences of LTD and LTP of synaptic inhibition strengths are intensively investigated via a microscopic method based on the distributions of time delays between the pre- and the post-synaptic spike times. Furthermore, we also investigate the effects of network architecture on FSS by changing the rewiring probability p of the SWN in the presence of iSTDP.
Collapse
Affiliation(s)
- Sang-Yoon Kim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu 42411, Republic of Korea.
| | - Woochang Lim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu 42411, Republic of Korea.
| |
Collapse
|
36
|
Rahmati N, Hoebeek FE, Peter S, De Zeeuw CI. Chloride Homeostasis in Neurons With Special Emphasis on the Olivocerebellar System: Differential Roles for Transporters and Channels. Front Cell Neurosci 2018; 12:101. [PMID: 29765304 PMCID: PMC5938380 DOI: 10.3389/fncel.2018.00101] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 03/28/2018] [Indexed: 12/14/2022] Open
Abstract
The intraneuronal ionic composition is an important determinant of brain functioning. There is growing evidence that aberrant homeostasis of the intracellular concentration of Cl- ([Cl-]i) evokes, in addition to that of Na+ and Ca2+, robust impairments of neuronal excitability and neurotransmission and thereby neurological conditions. More specifically, understanding the mechanisms underlying regulation of [Cl-]i is crucial for deciphering the variability in GABAergic and glycinergic signaling of neurons, in both health and disease. The homeostatic level of [Cl-]i is determined by various regulatory mechanisms, including those mediated by plasma membrane Cl- channels and transporters. This review focuses on the latest advances in identification, regulation and characterization of Cl- channels and transporters that modulate neuronal excitability and cell volume. By putting special emphasis on neurons of the olivocerebellar system, we establish that Cl- channels and transporters play an indispensable role in determining their [Cl-]i and thereby their function in sensorimotor coordination.
Collapse
Affiliation(s)
- Negah Rahmati
- Department of Neuroscience, Erasmus Medical Center, Rotterdam, Netherlands
| | - Freek E. Hoebeek
- Department of Neuroscience, Erasmus Medical Center, Rotterdam, Netherlands
- NIDOD Institute, Wilhelmina Children's Hospital, University Medical Center Utrecht and Brain Center Rudolf Magnus, Utrecht, Netherlands
| | - Saša Peter
- Department of Neuroscience, Erasmus Medical Center, Rotterdam, Netherlands
| | - Chris I. De Zeeuw
- Department of Neuroscience, Erasmus Medical Center, Rotterdam, Netherlands
- Netherlands Institute for Neuroscience, Royal Dutch Academy for Arts and Sciences, Amsterdam, Netherlands
| |
Collapse
|
37
|
LTP or LTD? Modeling the Influence of Stress on Synaptic Plasticity. eNeuro 2018; 5:eN-TNC-0242-17. [PMID: 29662939 PMCID: PMC5898787 DOI: 10.1523/eneuro.0242-17.2018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 01/15/2018] [Accepted: 01/21/2018] [Indexed: 01/03/2023] Open
Abstract
In cognitive memory, long-term potentiation (LTP) has been shown to occur when presynaptic and postsynaptic activities are highly correlated and glucocorticoid concentrations are in an optimal (i.e., low normal) range. In all other conditions, LTP is attenuated or even long-term depression (LTD) occurs. In this paper, we focus on NMDA receptor (NMDA-R)-dependent LTP and LTD, two processes involving various molecular mechanisms. To understand which of these mechanisms are indispensable for explaining the experimental evidence reported in the literature, we here propose a parsimonious model of NMDA-R-dependent synaptic plasticity. Central to this model are two processes. First, AMPA receptor-subunit trafficking; and second, glucocorticoid-dependent modifications of the brain-derived neurotrophic factor (BDNF)-receptor system. In 2008, we have published a core model, which contained the first process, while in the current paper we present an extended model, which also includes the second process. Using the extended model, we could show that stress attenuates LTP, while it enhances LTD. These simulation results are in agreement with experimental findings from other labs. In 2013, surprising experimental evidence showed that the GluA1 C-tail is unnecessary for LTP. When using our core model in its original form, our simulations already predicted that there would be no requirement for the GluA1 C-tail for LTP, allowing to eliminate a redundant mechanism from our model. In summary, we present a mathematical model that displays reduced complexity and is useful for explaining when and how LTP or LTD occurs at synapses during cognitive memory formation.
Collapse
|
38
|
Zhao J, Wang B, Wang X, Shang X. Up-regulation of Ca 2+/CaMKII/CREB signaling in salicylate-induced tinnitus in rats. Mol Cell Biochem 2018; 448:71-76. [PMID: 29427172 DOI: 10.1007/s11010-018-3314-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 02/01/2018] [Indexed: 01/09/2023]
Abstract
The purpose of the study was to investigate the changes of Ca2+/calmodulin-dependent protein kinases II (CaMKII)/cAMP response element-binding protein (CREB) signaling pathway in a rat tinnitus model. Eighteen Wistar rats were randomly divided into three groups: normal control (NC), normal saline (NS), and tinnitus model (TM) groups. Tinnitus model was induced by intraperitoneal injection of salicylate. The concentration of intracellular calcium level in auditory cortex cells was determined using Fura-2 acetoxymethyl ester (Fura-2 AM) method with fluorospectrophotometer. Expressions of calmodulin (CaM), N-methyl-D-aspartate receptor 2B subunit (NR2B), calcium-calmodulin kinase II (CaMKII), and cAMP response element-binding protein (CREB) were detected with Western blot. Tinnitus model was successfully established by the intraperitoneal administration of salicylate in rats. Compared with rats in NC and NS groups, salicylate administration significantly elevated CaM, NR2B, phospho-CaMKII and phospho-CREB expression in auditory cortex from tinnitus model group (p < 0.05), and the free intracellular Ca2+ concentrations (p < 0.05). Our data reveal that salicylate administration causes tinnitus symptoms and elevates Ca2+/CaMKII/CREB signaling pathway in auditory cortex cells. Our study likely provides a new understanding of the development of tinnitus.
Collapse
Affiliation(s)
- Jiuhan Zhao
- Department of Neurology, First Affiliated Hospital of China Medical University, No. 155 Nanjing North Street, Heping District, Shenyang, 110001, China
| | - Biao Wang
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, 110001, China
| | - Xiaohong Wang
- Department of Neurology, First Affiliated Hospital of China Medical University, No. 155 Nanjing North Street, Heping District, Shenyang, 110001, China
| | - Xiuli Shang
- Department of Neurology, First Affiliated Hospital of China Medical University, No. 155 Nanjing North Street, Heping District, Shenyang, 110001, China.
| |
Collapse
|
39
|
Aebersold MJ, Dermutz H, Demkó L, Cogollo JFS, Lin SC, Burchert C, Schneider M, Ling D, Forró C, Han H, Zambelli T, Vörös J. Local Chemical Stimulation of Neurons with the Fluidic Force Microscope (FluidFM). Chemphyschem 2017; 19:1234-1244. [DOI: 10.1002/cphc.201700780] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 10/06/2017] [Indexed: 01/06/2023]
Affiliation(s)
- Mathias J. Aebersold
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Harald Dermutz
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - László Demkó
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - José F. Saenz Cogollo
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Shiang-Chi Lin
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Conrad Burchert
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Moritz Schneider
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Doris Ling
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Csaba Forró
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Hana Han
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - Tomaso Zambelli
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| | - János Vörös
- Laboratory of Biosensors and Bioelectronics; Institute for Biomedical Engineering, University and ETH Zurich; Gloriastrasse 35 8092 Zurich Switzerland
| |
Collapse
|
40
|
Kwon W, Kim HS, Jeong J, Sung Y, Choi M, Park S, Lee J, Jang S, Kim SH, Lee S, Kim MO, Ryoo ZY. Tet1 overexpression leads to anxiety-like behavior and enhanced fear memories via the activation of calcium-dependent cascade through Egr1 expression in mice. FASEB J 2017; 32:390-403. [PMID: 28899881 DOI: 10.1096/fj.201601340rr] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 09/05/2017] [Indexed: 11/11/2022]
Abstract
Ten-eleven translocation methylcytosine dioxygenase 1 (Tet1) initiates DNA demethylation by converting 5-methylcytosine (5-mC) to 5-hydroxymethylcytosine (5-hmC) at CpG-rich regions of genes, which have key roles in adult neurogenesis and memory. In addition, the overexpression of Tet1 with 5-hmC alteration in patients with psychosis has also been reported, for instance in schizophrenia and bipolar disorders. The mechanism underlying Tet1 overexpression in the brain; however, is still elusive. In the present study, we found that Tet1-transgenic (Tet1-TG) mice displayed abnormal behaviors involving elevated anxiety and enhanced fear memories. We confirmed that Tet1 overexpression affected adult neurogenesis with oligodendrocyte differentiation in the hippocampal dentate gyrus of Tet1-TG mice. In addition, Tet1 overexpression induced the elevated expression of immediate early genes, such as Egr1, c-fos, Arc, and Bdnf, followed by the activation of intracellular calcium signals (i.e., CamKII, ERK, and CREB) in prefrontal and hippocampal neurons. The expression of GABA receptor subunits (Gabra2 and Gabra4) fluctuated in the prefrontal cortex and hippocampus. We evaluated the effects of Tet1 overexpression on intracellular calcium-dependent cascades by activating the Egr1 promoter in vitro Tet1 enhanced Egr1 expression, which may have led to alterations in Gabra2 and Gabra4 expression in neurons. Taken together, we suggest that the Tet1 overexpression in our Tet1-TG mice can be applied as an effective model for studying various stress-related diseases that show hyperactivation of intracellular calcium-dependent cascades in the brain.-Kwon, W., Kim, H.-S., Jeong, J., Sung, Y., Choi, M., Park, S., Lee, J., Jang, S., Kim, S. H., Lee, S., Kim, M. O., Ryoo, Z. Y. Tet1 overexpression leads to anxiety-like behavior and enhanced fear memories via the activation of calcium-dependent cascade through Egr1 expression in mice.
Collapse
Affiliation(s)
- Wookbong Kwon
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea
| | - Hyeng-Soo Kim
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea.,Institute of Life Science and Biotechnology, Kyungpook National University, Daegu, South Korea; and
| | - Jain Jeong
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea
| | - Yonghun Sung
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea
| | - Minjee Choi
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea
| | - Song Park
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea
| | - Jinhee Lee
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea
| | - Soyoung Jang
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea
| | - Sung Hyun Kim
- Institute of Life Science and Biotechnology, Kyungpook National University, Daegu, South Korea; and
| | - Sanggyu Lee
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea
| | - Myoung Ok Kim
- The School of Animal Biotechnology (BT) Science, Kyungpook National University, Sangju, South Korea
| | - Zae Young Ryoo
- School of Life Science, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea;
| |
Collapse
|
41
|
Lea-Carnall CA, Trujillo-Barreto NJ, Montemurro MA, El-Deredy W, Parkes LM. Evidence for frequency-dependent cortical plasticity in the human brain. Proc Natl Acad Sci U S A 2017; 114:8871-8876. [PMID: 28765375 PMCID: PMC5565407 DOI: 10.1073/pnas.1620988114] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Frequency-dependent plasticity (FDP) describes adaptation at the synapse in response to stimulation at different frequencies. Its consequence on the structure and function of cortical networks is unknown. We tested whether cortical "resonance," favorable stimulation frequencies at which the sensory cortices respond maximally, influenced the impact of FDP on perception, functional topography, and connectivity of the primary somatosensory cortex using psychophysics and functional imaging (fMRI). We costimulated two digits on the hand synchronously at, above, or below the resonance frequency of the somatosensory cortex, and tested subjects' accuracy and speed on tactile localization before and after costimulation. More errors and slower response times followed costimulation at above- or below-resonance, respectively. Response times were faster after at-resonance costimulation. In the fMRI, the cortical representations of the two digits costimulated above-resonance shifted closer, potentially accounting for the poorer performance. Costimulation at-resonance did not shift the digit regions, but increased the functional coupling between them, potentially accounting for the improved response time. To relate these results to synaptic plasticity, we simulated a network of oscillators incorporating Hebbian learning. Two neighboring patches embedded in a cortical sheet, mimicking the two digit regions, were costimulated at different frequencies. Network activation outside the stimulated patches was greatest at above-resonance frequencies, reproducing the spread of digit representations seen with fMRI. Connection strengths within the patches increased following at-resonance costimulation, reproducing the increased fMRI connectivity. We show that FDP extends to the cortical level and is influenced by cortical resonance.
Collapse
Affiliation(s)
- Caroline A Lea-Carnall
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom;
| | - Nelson J Trujillo-Barreto
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Marcelo A Montemurro
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Wael El-Deredy
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
- School of Biomedical Engineering, University of Valparaiso, Valparaiso 2366103, Chile
| | - Laura M Parkes
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| |
Collapse
|
42
|
Bannai H. Molecular membrane dynamics: Insights into synaptic function and neuropathological disease. Neurosci Res 2017; 129:47-56. [PMID: 28826905 DOI: 10.1016/j.neures.2017.07.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 07/14/2017] [Accepted: 07/26/2017] [Indexed: 11/19/2022]
Abstract
The fluid mosaic model states that molecules in the plasma membrane can freely undergo lateral diffusion; however, in neurons and glia, specific membrane molecules are concentrated in cellular microdomains to overcome the randomizing effects of free diffusion. This specialized distribution of membrane molecules is crucial for various cell functions; one example is the accumulation of neurotransmitter receptors at the postsynaptic neuronal membrane, which enables efficient synaptic transmission. Quantum dot-single particle tracking (QD-SPT) is a super-resolution imaging technique that uses semiconductor nanocrystal quantum dots as fluorescent probes, and is a powerful tool for analyzing protein and lipid behavior in the plasma membrane. In this article, we review studies implementing QD-SPT in neuroscience research and important data gleaned using this technology. Recent QD-SPT experiments have provided critical insights into the mechanism and physiological relevance of membrane self-organization in neurons and astrocytes in the brain. The mobility of some membrane molecules may become abnormal in cellular models of epilepsy and Alzheimer's disease. Based on these findings, we propose that the behavior of membrane molecules reflects the condition of neurons in pathological disease states.
Collapse
Affiliation(s)
- Hiroko Bannai
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute (BSI), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Japan Science and Technology Agency, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
| |
Collapse
|
43
|
Hennequin G, Agnes EJ, Vogels TP. Inhibitory Plasticity: Balance, Control, and Codependence. Annu Rev Neurosci 2017; 40:557-579. [DOI: 10.1146/annurev-neuro-072116-031005] [Citation(s) in RCA: 140] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Guillaume Hennequin
- Computational and Biological Learning Lab, Department of Engineering, University of Cambridge, Cambridge CB2 3EJ, United Kingdom
| | - Everton J. Agnes
- Centre for Neural Circuits and Behaviour, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3SR, United Kingdom
| | - Tim P. Vogels
- Centre for Neural Circuits and Behaviour, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3SR, United Kingdom
| |
Collapse
|
44
|
Tyebji S, Hannan AJ. Synaptopathic mechanisms of neurodegeneration and dementia: Insights from Huntington's disease. Prog Neurobiol 2017; 153:18-45. [PMID: 28377290 DOI: 10.1016/j.pneurobio.2017.03.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 03/19/2017] [Accepted: 03/30/2017] [Indexed: 12/20/2022]
Abstract
Dementia encapsulates a set of symptoms that include loss of mental abilities such as memory, problem solving or language, and reduces a person's ability to perform daily activities. Alzheimer's disease is the most common form of dementia, however dementia can also occur in other neurological disorders such as Huntington's disease (HD). Many studies have demonstrated that loss of neuronal cell function manifests pre-symptomatically and thus is a relevant therapeutic target to alleviate symptoms. Synaptopathy, the physiological dysfunction of synapses, is now being approached as the target for many neurological and psychiatric disorders, including HD. HD is an autosomal dominant and progressive degenerative disorder, with clinical manifestations that encompass movement, cognition, mood and behaviour. HD is one of the most common tandem repeat disorders and is caused by a trinucleotide (CAG) repeat expansion, encoding an extended polyglutamine tract in the huntingtin protein. Animal models as well as human studies have provided detailed, although not exhaustive, evidence of synaptic dysfunction in HD. In this review, we discuss the neuropathology of HD and how the changes in synaptic signalling in the diseased brain lead to its symptoms, which include dementia. Here, we review and discuss the mechanisms by which the 'molecular orchestras' and their 'synaptic symphonies' are disrupted in neurodegeneration and dementia, focusing on HD as a model disease. We also explore the therapeutic strategies currently in pre-clinical and clinical testing that are targeted towards improving synaptic function in HD.
Collapse
Affiliation(s)
- Shiraz Tyebji
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia; Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Victoria, Australia.
| |
Collapse
|
45
|
Domínguez S, Fernández de Sevilla D, Buño W. Muscarinic Long-Term Enhancement of Tonic and Phasic GABA A Inhibition in Rat CA1 Pyramidal Neurons. Front Cell Neurosci 2016; 10:244. [PMID: 27833531 PMCID: PMC5080370 DOI: 10.3389/fncel.2016.00244] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 10/06/2016] [Indexed: 01/23/2023] Open
Abstract
Acetylcholine (ACh) regulates network operation in the hippocampus by controlling excitation and inhibition in rat CA1 pyramidal neurons (PCs), the latter through gamma-aminobutyric acid type-A receptors (GABAARs). Although, the enhancing effects of ACh on GABAARs have been reported (Dominguez et al., 2014, 2015), its role in regulating tonic GABAA inhibition has not been explored in depth. Therefore, we aimed at determining the effects of the activation of ACh receptors on responses mediated by synaptic and extrasynaptic GABAARs. Here, we show that under blockade of ionotropic glutamate receptors ACh, acting through muscarinic type 1 receptors, paired with post-synaptic depolarization induced a long-term enhancement of tonic GABAA currents (tGABAA) and puff-evoked GABAA currents (pGABAA). ACh combined with depolarization also potentiated IPSCs (i.e., phasic inhibition) in the same PCs, without signs of interactions of synaptic responses with pGABAA and tGABAA, suggesting the contribution of two different GABAA receptor pools. The long-term enhancement of GABAA currents and IPSCs reduced the excitability of PCs, possibly regulating plasticity and learning in behaving animals.
Collapse
Affiliation(s)
- Soledad Domínguez
- Instituto Cajal - Consejo Superior de Investigaciones CientificasMadrid, Spain; Centre National de la Recherche Scientifique, Paris Descartes University, UMR 8118, ParisFrance
| | - David Fernández de Sevilla
- Instituto Cajal - Consejo Superior de Investigaciones CientificasMadrid, Spain; Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autonoma de MadridMadrid, Spain
| | - Washington Buño
- Instituto Cajal - Consejo Superior de Investigaciones Cientificas Madrid, Spain
| |
Collapse
|
46
|
Mele M, Leal G, Duarte CB. Role of GABAAR trafficking in the plasticity of inhibitory synapses. J Neurochem 2016; 139:997-1018. [DOI: 10.1111/jnc.13742] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 07/12/2016] [Accepted: 07/13/2016] [Indexed: 12/22/2022]
Affiliation(s)
- Miranda Mele
- Center for Neuroscience and Cell Biology; University of Coimbra; Coimbra Portugal
| | - Graciano Leal
- Center for Neuroscience and Cell Biology; University of Coimbra; Coimbra Portugal
| | - Carlos B. Duarte
- Center for Neuroscience and Cell Biology; University of Coimbra; Coimbra Portugal
- Department of Life Sciences; University of Coimbra; Coimbra Portugal
| |
Collapse
|
47
|
Pamenter ME, Powell FL. Time Domains of the Hypoxic Ventilatory Response and Their Molecular Basis. Compr Physiol 2016; 6:1345-85. [PMID: 27347896 DOI: 10.1002/cphy.c150026] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ventilatory responses to hypoxia vary widely depending on the pattern and length of hypoxic exposure. Acute, prolonged, or intermittent hypoxic episodes can increase or decrease breathing for seconds to years, both during the hypoxic stimulus, and also after its removal. These myriad effects are the result of a complicated web of molecular interactions that underlie plasticity in the respiratory control reflex circuits and ultimately control the physiology of breathing in hypoxia. Since the time domains of the physiological hypoxic ventilatory response (HVR) were identified, considerable research effort has gone toward elucidating the underlying molecular mechanisms that mediate these varied responses. This research has begun to describe complicated and plastic interactions in the relay circuits between the peripheral chemoreceptors and the ventilatory control circuits within the central nervous system. Intriguingly, many of these molecular pathways seem to share key components between the different time domains, suggesting that varied physiological HVRs are the result of specific modifications to overlapping pathways. This review highlights what has been discovered regarding the cell and molecular level control of the time domains of the HVR, and highlights key areas where further research is required. Understanding the molecular control of ventilation in hypoxia has important implications for basic physiology and is emerging as an important component of several clinical fields. © 2016 American Physiological Society. Compr Physiol 6:1345-1385, 2016.
Collapse
Affiliation(s)
| | - Frank L Powell
- Physiology Division, Department of Medicine, University of California San Diego, La Jolla, California, USA
| |
Collapse
|
48
|
Kim D, Samarth P, Feng F, Pare D, Nair SS. Synaptic competition in the lateral amygdala and the stimulus specificity of conditioned fear: a biophysical modeling study. Brain Struct Funct 2016; 221:2163-82. [PMID: 25859631 PMCID: PMC4600426 DOI: 10.1007/s00429-015-1037-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 03/31/2015] [Indexed: 12/20/2022]
Abstract
Competitive synaptic interactions between principal neurons (PNs) with differing intrinsic excitability were recently shown to determine which dorsal lateral amygdala (LAd) neurons are recruited into a fear memory trace. Here, we explored the contribution of these competitive interactions in determining the stimulus specificity of conditioned fear associations. To this end, we used a realistic biophysical computational model of LAd that included multi-compartment conductance-based models of 800 PNs and 200 interneurons. To reproduce the continuum of spike frequency adaptation displayed by PNs, the model included three subtypes of PNs with high, intermediate, and low spike frequency adaptation. In addition, the model network integrated spatially differentiated patterns of excitatory and inhibitory connections within LA, dopaminergic and noradrenergic inputs, extrinsic thalamic and cortical tone afferents to simulate conditioned stimuli as well as shock inputs for the unconditioned stimulus. Last, glutamatergic synapses in the model could undergo activity-dependent plasticity. Our results suggest that plasticity at both excitatory (PN-PN) and di-synaptic inhibitory (PN-ITN and, particularly, ITN-PN) connections are major determinants of the synaptic competition governing the assignment of PNs to the memory trace. The model also revealed that training-induced potentiation of PN-PN synapses promotes, whereas that of ITN-PN synapses opposes, stimulus generalization. Indeed, suppressing plasticity of PN-PN synapses increased, whereas preventing plasticity of interneuronal synapses decreased the CS specificity of PN recruitment. Overall, our results indicate that the plasticity configuration imprinted in the network by synaptic competition ensures memory specificity. Given that anxiety disorders are characterized by tendency to generalize learned fear to safe stimuli or situations, understanding how plasticity of intrinsic LAd synapses regulates the specificity of learned fear is an important challenge for future experimental studies.
Collapse
Affiliation(s)
- D Kim
- Electrical and Computer Engineering, University of Missouri, Columbia, MO, 65211, USA
| | - P Samarth
- Electrical and Computer Engineering, University of Missouri, Columbia, MO, 65211, USA
| | - F Feng
- Electrical and Computer Engineering, University of Missouri, Columbia, MO, 65211, USA
| | - D Pare
- Center for Molecular and Behavioral Neuroscience, Rutgers, The State University of New Jersey, 197 University Avenue, Newark, NJ, 07102, USA
| | - Satish S Nair
- Electrical and Computer Engineering, University of Missouri, Columbia, MO, 65211, USA.
| |
Collapse
|
49
|
Chaudhury S, Sharma V, Kumar V, Nag TC, Wadhwa S. Activity-dependent synaptic plasticity modulates the critical phase of brain development. Brain Dev 2016; 38:355-63. [PMID: 26515724 DOI: 10.1016/j.braindev.2015.10.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 09/21/2015] [Accepted: 10/10/2015] [Indexed: 12/28/2022]
Abstract
Plasticity or neuronal plasticity is a unique and adaptive feature of nervous system which allows neurons to reorganize their interactions in response to an intrinsic or extrinsic stimulation and shapes the formation and maintenance of a functional neuronal circuit. Synaptic plasticity is the most important form of neural plasticity and plays critical role during the development allowing the formation of precise neural connectivity via the process of pruning. In the sensory systems-auditory and visual, this process is heavily dependent on the external cues perceived during the development. Environmental enrichment paradigms in an activity-dependent manner result in early maturation of the synapses and more efficient trans-synaptic signaling or communication flow. This has been extensively observed in the avian auditory system. On the other hand, stimuli results in negative effect can cause alterations in the synaptic connectivity and strength resulting in various developmental brain disorders including autism, fragile X syndrome and rett syndrome. In this review we discuss the role of different forms of activity (spontaneous or environmental) during the development of the nervous system in modifying synaptic plasticity necessary for shaping the adult brain. Also, we try to explore various factors (molecular, genetic and epigenetic) involved in altering the synaptic plasticity in positive and negative way.
Collapse
Affiliation(s)
- Sraboni Chaudhury
- Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Vikram Sharma
- Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Vivek Kumar
- Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Tapas C Nag
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Shashi Wadhwa
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi 110029, India
| |
Collapse
|
50
|
Plasticity of Hippocampal Excitatory-Inhibitory Balance: Missing the Synaptic Control in the Epileptic Brain. Neural Plast 2016; 2016:8607038. [PMID: 27006834 PMCID: PMC4783563 DOI: 10.1155/2016/8607038] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 01/20/2016] [Accepted: 01/31/2016] [Indexed: 11/24/2022] Open
Abstract
Synaptic plasticity is the capacity generated by experience to modify the neural function and, thereby, adapt our behaviour. Long-term plasticity of glutamatergic and GABAergic transmission occurs in a concerted manner, finely adjusting the excitatory-inhibitory (E/I) balance. Imbalances of E/I function are related to several neurological diseases including epilepsy. Several evidences have demonstrated that astrocytes are able to control the synaptic plasticity, with astrocytes being active partners in synaptic physiology and E/I balance. Here, we revise molecular evidences showing the epileptic stage as an abnormal form of long-term brain plasticity and propose the possible participation of astrocytes to the abnormal increase of glutamatergic and decrease of GABAergic neurotransmission in epileptic networks.
Collapse
|