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Tsai YC, Huang SM, Peng HH, Lin SW, Lin SR, Chin TY, Huang SM. Imbalance of synaptic and extrasynaptic NMDA receptors induced by the deletion of CRMP1 accelerates age-related cognitive decline in mice. Neurobiol Aging 2024; 135:48-59. [PMID: 38176125 DOI: 10.1016/j.neurobiolaging.2023.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 12/25/2023] [Accepted: 12/27/2023] [Indexed: 01/06/2024]
Abstract
Collapsin response mediator protein 1 (CRMP1) is involved in semaphorin 3A signaling pathway, promoting neurite extension and growth cone collapse. It is highly expressed in the nervous system, especially the hippocampus. The crmp1 knockout (KO) mice display impaired spatial learning and memory, and this phenomenon seemingly tends to deteriorate with age. Here we investigated whether CRMP1 is involved in age-related cognitive decline in WT and crmp1 KO mice at adult, middle-aged and older stages. The results revealed that cognitive dysfunction in the Morris water maze task became more severe and decreased glutamate and glutamine level in middle-aged crmp1 KO mice. Additionally, increasing levels of extrasynaptic NMDA receptors and phosphorylation of Tau were observed in middle-aged crmp1 KO mice, leading to synaptic and neuronal loss in the CA3 regions of hippocampus. These findings suggest that deletion of CRMP1 accelerates age-related cognitive decline by disrupting the balance between synaptic and extrasynaptic NMDA receptors, resulting in the loss of synapses and neurons.
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Affiliation(s)
- Yun-Chieh Tsai
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Sheng-Min Huang
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, Taiwan
| | - Hsu-Hsia Peng
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Shu-Wha Lin
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shu-Rung Lin
- Department of Bioscience Technology, Chung Yuan Christian University, Taoyuan, Taiwan.
| | - Ting-Yu Chin
- Department of Bioscience Technology, Chung Yuan Christian University, Taoyuan, Taiwan.
| | - Shih-Ming Huang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan; Department of Biochemistry, National Defense Medical Center, Taipei, Taiwan.
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2
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Kuchtiak V, Smejkalova T, Horak M, Vyklicky L, Balik A. Analysis of Surface Expression of NMDAR Subunits in Primary Hippocampal Neurons. Methods Mol Biol 2024; 2799:29-46. [PMID: 38727901 DOI: 10.1007/978-1-0716-3830-9_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/03/2024]
Abstract
The expression and activity of ionotropic glutamate receptors control signal transduction at the excitatory synapses in the CNS. The NMDAR comprises two obligatory GluN1 subunits and two GluN2 or GluN3 subunits in different combinations. Each GluN subunit consists of four domains: the extracellular amino-terminal and agonist-binding domains, the transmembrane domain, and the intracellular C-terminal domain (CTD). The CTD interaction with various classes of intracellular proteins is critical for trafficking and synaptic localization of NMDARs. Amino acid mutations or the inclusion of premature stop codons in the CTD could contribute to the emergence of neurodevelopmental and neuropsychiatric disorders. Here, we describe the method of preparing primary hippocampal neurons and lentiviral particles expressing GluN subunits that can be used as a model to study cell surface expression and synaptic localization of NMDARs. We also show a simple method of fluorescence immunostaining of eGFP-tagged GluN2 subunits and subsequent microscopy technique and image analysis to study the effects of disease-associated mutations in the CTDs of GluN2A and GluN2B subunits.
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Affiliation(s)
- Viktor Kuchtiak
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Tereza Smejkalova
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Martin Horak
- Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic
| | - Ladislav Vyklicky
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Ales Balik
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
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3
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Chandravanshi LP, Agrawal P, Darwish HW, Trigun SK. Impairments of Spatial Memory and N-methyl-d-aspartate Receptors and Their Postsynaptic Signaling Molecules in the Hippocampus of Developing Rats Induced by As, Pb, and Mn Mixture Exposure. Brain Sci 2023; 13:1715. [PMID: 38137163 PMCID: PMC10742016 DOI: 10.3390/brainsci13121715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 11/24/2023] [Accepted: 11/29/2023] [Indexed: 12/24/2023] Open
Abstract
Exposure to metal mixtures is recognized as a real-life scenario, needing novel studies that can assess their complex effects on brain development. There is still a significant public health concern associated with chronic low levels of metal exposure. In contrast to other metals, these three metals (As, Pb, and Mn) are commonly found in various environmental and industrial contexts. In addition to additive or synergistic interactions, concurrent exposure to this metal mixture may also have neurotoxic effects that differ from those caused by exposure to single components. The NMDA receptor and several important signaling proteins are involved in learning, memory, and synaptic plasticity in the hippocampus, including CaMKII, postsynaptic density protein-95 (PSD-95), synaptic Ras GTPase activating protein (SynGAP), a negative regulator of Ras-MAPK activity, and CREB. We hypothesized that alterations in the above molecular players may contribute to metal mixture developmental neurotoxicity. Thus, the aim of this study was to investigate the effect of these metals and their mixture at low doses (As 4 mg, Pb 4 mg, and Mn 10 mg/kg bw/p.o) on NMDA receptors and their postsynaptic signaling proteins during developing periods (GD6 to PD59) of the rat brain. Rats exposed to As, Pb, and Mn individually or at the same doses in a triple-metal mixture (MM) showed impairments in learning and memory functions in comparison to the control group rats. Declined protein expressions of NR2A, PSD-95, p- CaMKII, and pCREB were observed in the metal mix-exposed rats, while the expression of SynGAP was found to be enhanced in the hippocampus as compared to the controls on PD60. Thereby, our data suggest that alterations in the NMDA receptor complex and postsynaptic signaling proteins could explain the cognitive dysfunctions caused by metal-mixture-induced developmental neurotoxicity in rats. These outcomes indicate that incessant metal mixture exposure may have detrimental consequences on brain development.
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Affiliation(s)
- Lalit P. Chandravanshi
- Department of Forensic Science, Sharda University, Greater Noida 201308, India; (L.P.C.); (P.A.)
| | - Prashant Agrawal
- Department of Forensic Science, Sharda University, Greater Noida 201308, India; (L.P.C.); (P.A.)
| | - Hany W. Darwish
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia
| | - Surendra Kumar Trigun
- Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
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4
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Lorenz-Guertin JM, Povysheva N, Chapman CA, MacDonald ML, Fazzari M, Nigam A, Nuwer JL, Das S, Brady ML, Vajn K, Bambino MJ, Weintraub ST, Johnson JW, Jacob TC. Inhibitory and excitatory synaptic neuroadaptations in the diazepam tolerant brain. Neurobiol Dis 2023; 185:106248. [PMID: 37536384 PMCID: PMC10578451 DOI: 10.1016/j.nbd.2023.106248] [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: 05/12/2023] [Revised: 07/20/2023] [Accepted: 07/31/2023] [Indexed: 08/05/2023] Open
Abstract
Benzodiazepine (BZ) drugs treat seizures, anxiety, insomnia, and alcohol withdrawal by potentiating γ2 subunit containing GABA type A receptors (GABAARs). BZ clinical use is hampered by tolerance and withdrawal symptoms including heightened seizure susceptibility, panic, and sleep disturbances. Here, we investigated inhibitory GABAergic and excitatory glutamatergic plasticity in mice tolerant to benzodiazepine sedation. Repeated diazepam (DZP) treatment diminished sedative effects and decreased DZP potentiation of GABAAR synaptic currents without impacting overall synaptic inhibition. While DZP did not alter γ2-GABAAR subunit composition, there was a redistribution of extrasynaptic GABAARs to synapses, resulting in higher levels of synaptic BZ-insensitive α4-containing GABAARs and a concomitant reduction in tonic inhibition. Conversely, excitatory glutamatergic synaptic transmission was increased, and NMDAR subunits were upregulated at synaptic and total protein levels. Quantitative proteomics further revealed cortex neuroadaptations of key pro-excitatory mediators and synaptic plasticity pathways highlighted by Ca2+/calmodulin-dependent protein kinase II (CAMKII), MAPK, and PKC signaling. Thus, reduced inhibitory GABAergic tone and elevated glutamatergic neurotransmission contribute to disrupted excitation/inhibition balance and reduced BZ therapeutic power with benzodiazepine tolerance.
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Affiliation(s)
- Joshua M Lorenz-Guertin
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Nadya Povysheva
- Department of Neuroscience and Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Caitlyn A Chapman
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Matthew L MacDonald
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Marco Fazzari
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Aparna Nigam
- Department of Neuroscience and Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jessica L Nuwer
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Sabyasachi Das
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Megan L Brady
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Katarina Vajn
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Matthew J Bambino
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Susan T Weintraub
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antoni, TX, USA
| | - Jon W Johnson
- Department of Neuroscience and Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tija C Jacob
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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5
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Huffels CFM, Middeldorp J, Hol EM. Aß Pathology and Neuron-Glia Interactions: A Synaptocentric View. Neurochem Res 2023; 48:1026-1046. [PMID: 35976488 PMCID: PMC10030451 DOI: 10.1007/s11064-022-03699-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 06/30/2022] [Accepted: 07/15/2022] [Indexed: 10/15/2022]
Abstract
Alzheimer's disease (AD) causes the majority of dementia cases worldwide. Early pathological hallmarks include the accumulation of amyloid-ß (Aß) and activation of both astrocytes and microglia. Neurons form the building blocks of the central nervous system, and astrocytes and microglia provide essential input for its healthy functioning. Their function integrates at the level of the synapse, which is therefore sometimes referred to as the "quad-partite synapse". Increasing evidence puts AD forward as a disease of the synapse, where pre- and postsynaptic processes, as well as astrocyte and microglia functioning progressively deteriorate. Here, we aim to review the current knowledge on how Aß accumulation functionally affects the individual components of the quad-partite synapse. We highlight a selection of processes that are essential to the healthy functioning of the neuronal synapse, including presynaptic neurotransmitter release and postsynaptic receptor functioning. We further discuss how Aß affects the astrocyte's capacity to recycle neurotransmitters, release gliotransmitters, and maintain ion homeostasis. We additionally review literature on how Aß changes the immunoprotective function of microglia during AD progression and conclude by summarizing our main findings and highlighting the challenges in current studies, as well as the need for further research.
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Affiliation(s)
- Christiaan F M Huffels
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Jinte Middeldorp
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
- Department of Neurobiology & Aging, Biomedical Primate Research Centre, Rijswijk, The Netherlands
| | - Elly M Hol
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands.
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6
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Naylor DE. In the fast lane: Receptor trafficking during status epilepticus. Epilepsia Open 2023; 8 Suppl 1:S35-S65. [PMID: 36861477 PMCID: PMC10173858 DOI: 10.1002/epi4.12718] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 02/23/2023] [Indexed: 03/03/2023] Open
Abstract
Status epilepticus (SE) remains a significant cause of morbidity and mortality and often is refractory to standard first-line treatments. A rapid loss of synaptic inhibition and development of pharmacoresistance to benzodiazepines (BZDs) occurs early during SE, while NMDA and AMPA receptor antagonists remain effective treatments after BZDs have failed. Multimodal and subunit-selective receptor trafficking within minutes to an hour of SE involves GABA-A, NMDA, and AMPA receptors and contributes to shifts in the number and subunit composition of surface receptors with differential impacts on the physiology, pharmacology, and strength of GABAergic and glutamatergic currents at synaptic and extrasynaptic sites. During the first hour of SE, synaptic GABA-A receptors containing γ2 subunits move to the cell interior while extrasynaptic GABA-A receptors with δ subunits are preserved. Conversely, NMDA receptors containing N2B subunits are increased at synaptic and extrasynaptic sites, and homomeric GluA1 ("GluA2-lacking") calcium permeant AMPA receptor surface expression also is increased. Molecular mechanisms, largely driven by NMDA receptor or calcium permeant AMPA receptor activation early during circuit hyperactivity, regulate subunit-specific interactions with proteins involved with synaptic scaffolding, adaptin-AP2/clathrin-dependent endocytosis, endoplasmic reticulum (ER) retention, and endosomal recycling. Reviewed here is how SE-induced shifts in receptor subunit composition and surface representation increase the excitatory to inhibitory imbalance that sustains seizures and fuels excitotoxicity contributing to chronic sequela such as "spontaneous recurrent seizures" (SRS). A role for early multimodal therapy is suggested both for treatment of SE and for prevention of long-term comorbidities.
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Affiliation(s)
- David E Naylor
- VA Greater Los Angeles Healthcare System, Department of Neurology, David Geffen School of Medicine at UCLA, and The Lundquist Institute at Harbor-UCLA Medical Center, Los Angeles, California, USA
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7
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Kleinjan MS, Buchta WC, Ogelman R, Hwang IW, Kuwajima M, Hubbard DD, Kareemo DJ, Prikhodko O, Olah SL, Gomez Wulschner LE, Abraham WC, Franco SJ, Harris KM, Oh WC, Kennedy MJ. Dually innervated dendritic spines develop in the absence of excitatory activity and resist plasticity through tonic inhibitory crosstalk. Neuron 2023; 111:362-371.e6. [PMID: 36395772 PMCID: PMC9899020 DOI: 10.1016/j.neuron.2022.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 07/13/2022] [Accepted: 10/31/2022] [Indexed: 11/17/2022]
Abstract
Dendritic spines can be directly connected to both inhibitory and excitatory presynaptic terminals, resulting in nanometer-scale proximity of opposing synaptic functions. While dually innervated spines (DiSs) are observed throughout the central nervous system, their developmental timeline and functional properties remain uncharacterized. Here we used a combination of serial section electron microscopy, live imaging, and local synapse activity manipulations to investigate DiS development and function in rodent hippocampus. Dual innervation occurred early in development, even on spines where the excitatory input was locally silenced. Synaptic NMDA receptor currents were selectively reduced at DiSs through tonic GABAB receptor signaling. Accordingly, spine enlargement normally associated with long-term potentiation on singly innervated spines (SiSs) was blocked at DiSs. Silencing somatostatin interneurons or pharmacologically blocking GABABRs restored NMDA receptor function and structural plasticity to levels comparable to neighboring SiSs. Thus, hippocampal DiSs are stable structures where function and plasticity are potently regulated by nanometer-scale GABAergic signaling.
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Affiliation(s)
- Mason S Kleinjan
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - William C Buchta
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Roberto Ogelman
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - In-Wook Hwang
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Masaaki Kuwajima
- Department of Neuroscience, University of Texas at Austin, Austin, TX 78712, USA
| | - Dusten D Hubbard
- Department of Neuroscience, University of Texas at Austin, Austin, TX 78712, USA
| | - Dean J Kareemo
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Olga Prikhodko
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Samantha L Olah
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Luis E Gomez Wulschner
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Wickliffe C Abraham
- Department of Psychology, Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Santos J Franco
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Kristen M Harris
- Department of Neuroscience, University of Texas at Austin, Austin, TX 78712, USA
| | - Won Chan Oh
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA.
| | - Matthew J Kennedy
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA.
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8
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Ferreyra S, González S. Therapeutic potential of progesterone in spinal cord injury-induced neuropathic pain: At the crossroads between neuroinflammation and N-methyl-D-aspartate receptor. J Neuroendocrinol 2023; 35:e13181. [PMID: 35924434 DOI: 10.1111/jne.13181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/13/2022] [Accepted: 06/19/2022] [Indexed: 10/17/2022]
Abstract
In recent decades, an area of active research has supported the notion that progesterone promotes a wide range of remarkable protective actions in experimental models of nervous system trauma or disease, and has also provided a strong basis for considering this steroid as a promising molecule for modulating the complex maladaptive changes that lead to neuropathic pain, especially after spinal cord injury. In this review, we intend to give the readers a brief appraisal of the main mechanisms underlying the increased excitability of the spinal circuit in the pain pathway after trauma, with particular emphasis on those mediated by the activation of resident glial cells, the subsequent release of proinflammatory cytokines and their impact on N-methyl-D-aspartate receptor function. We then summarize the available preclinical data pointing to progesterone as a valuable repurposing molecule for blocking critical cellular and molecular events that occur in the dorsal horn of the injured spinal cord and are related to the development of chronic pain. Since the treatment and management of neuropathic pain after spinal injury remains challenging, the potential therapeutic value of progesterone opens new traslational perspectives to prevent central pain.
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Affiliation(s)
- Sol Ferreyra
- Instituto de Biología y Medicina Experimental, Laboratorio de Nocicepción y Dolor Neuropático, CONICET, Buenos Aires, Argentina
| | - Susana González
- Instituto de Biología y Medicina Experimental, Laboratorio de Nocicepción y Dolor Neuropático, CONICET, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Buenos Aires, Argentina
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9
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Dumanska H, Veselovsky N. Protein kinase C mediates hypoxia-induced long-term potentiation of NMDA neurotransmission in the visual retinocollicular pathway. Front Cell Neurosci 2023; 17:1141689. [PMID: 36909286 PMCID: PMC9998674 DOI: 10.3389/fncel.2023.1141689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 02/13/2023] [Indexed: 03/14/2023] Open
Abstract
The identification of processes and mechanisms underlying the early stage of hypoxic injury of the retinocollicular pathway may be beneficial for the future prevention and treatment of navigation, orientation, and visual attention impairments. Previously, we have demonstrated that short-term hypoxia led to long-term potentiation (LTP) of NMDA neurotransmission in the background of long-term depression of GABAA retinocollicular transmission. Here, we sought to obtain insight into the mechanisms of hypoxia-induced LTP of NMDA retinocollicular neurotransmission and the role of the protein kinase C (PKC) signaling pathway in it. To investigate these, we recorded pharmacologically isolated NMDA transmission in cocultivated pairs of rat retinal ganglion cells and superficial superior colliculus neurons under normoxic and hypoxic conditions, using the paired patch-clamp technique and method of fast local superfusion. We tested the involvement of the PKC by adding the potent and selective inhibitor chelerythrine chloride (ChC, 5 μM). We observed that hypoxia-induced LTP of NMDA neurotransmission is associated with the shortening of current kinetics. We also found that the PKC signaling pathway mediates hypoxia-induced LTP and associated shortening of NMDA currents. The ChC completely blocked the induction of LTP by hypoxia and associated kinetic changes. Contrary effects of ChC were observed with already induced LTP. ChC led to the reversal of LTP to the initial synaptic strength but the current kinetics remain irreversibly shortened. Our results show that ChC is a promising agent for the prevention and treatment of hypoxic injuries of NMDA retinocollicular neurotransmission and provide necessary electrophysiological basics for further research.
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Affiliation(s)
- Hanna Dumanska
- Department of Neuronal Network Physiology, Bogomoletz Institute of Physiology, National Academy of Science of Ukraine, Kyiv, Ukraine
| | - Nikolai Veselovsky
- Department of Neuronal Network Physiology, Bogomoletz Institute of Physiology, National Academy of Science of Ukraine, Kyiv, Ukraine
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10
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Targeting NMDA Receptors in Emotional Disorders: Their Role in Neuroprotection. Brain Sci 2022; 12:brainsci12101329. [PMID: 36291261 PMCID: PMC9599159 DOI: 10.3390/brainsci12101329] [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: 09/01/2022] [Revised: 09/28/2022] [Accepted: 09/28/2022] [Indexed: 12/03/2022] Open
Abstract
Excitatory glutamatergic neurotransmission mediated through N-methyl-D-Aspartate (NMDA) receptors (NMDARs) is essential for synaptic plasticity and neuronal survival. While under pathological states, abnormal NMDAR activation is involved in the occurrence and development of psychiatric disorders, which suggests a directional modulation of NMDAR activity that contributes to the remission and treatment of psychiatric disorders. This review thus focuses on the involvement of NMDARs in the pathophysiological processes of psychiatric mood disorders and analyzes the neuroprotective mechanisms of NMDARs. Firstly, we introduce NMDAR-mediated neural signaling pathways in brain function and mood regulation as well as the pathophysiological mechanisms of NMDARs in emotion-related mental disorders such as anxiety and depression. Then, we provide an in-depth summary of current NMDAR modulators that have the potential to be developed into clinical drugs and their pharmacological research achievements in the treatment of anxiety and depression. Based on these findings, drug-targeting for NMDARs might open up novel territory for the development of therapeutic agents for refractory anxiety and depression.
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11
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Liu X, Hua F, Yang D, Lin Y, Zhang L, Ying J, Sheng H, Wang X. Roles of neuroligins in central nervous system development: focus on glial neuroligins and neuron neuroligins. Lab Invest 2022; 20:418. [PMID: 36088343 PMCID: PMC9463862 DOI: 10.1186/s12967-022-03625-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/01/2022] [Indexed: 11/10/2022]
Abstract
Neuroligins are postsynaptic cell adhesion molecules that are relevant to many neurodevelopmental disorders. They are differentially enriched at the postsynapse and interact with their presynaptic ligands, neurexins, whose differential binding to neuroligins has been shown to regulate synaptogenesis, transmission, and other synaptic properties. The proper functioning of functional networks in the brain depends on the proper connection between neuronal synapses. Impaired synaptogenesis or synaptic transmission results in synaptic dysfunction, and these synaptic pathologies are the basis for many neurodevelopmental disorders. Deletions or mutations in the neuroligins genes have been found in patients with both autism and schizophrenia. It is because of the important role of neuroligins in synaptic connectivity and synaptic dysfunction that studies on neuroligins in the past have mainly focused on their expression in neurons. As studies on the expression of genes specific to various cells of the central nervous system deepened, neuroligins were found to be expressed in non-neuronal cells as well. In the central nervous system, glial cells are the most representative non-neuronal cells, which can also express neuroligins in large amounts, especially astrocytes and oligodendrocytes, and they are involved in the regulation of synaptic function, as are neuronal neuroligins. This review examines the mechanisms of neuron neuroligins and non-neuronal neuroligins in the central nervous system and also discusses the important role of neuroligins in the development of the central nervous system and neurodevelopmental disorders from the perspective of neuronal neuroligins and glial neuroligins.
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12
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Mancini M, Patel JC, Affinati AH, Witkovsky P, Rice ME. Leptin Promotes Striatal Dopamine Release via Cholinergic Interneurons and Regionally Distinct Signaling Pathways. J Neurosci 2022; 42:6668-6679. [PMID: 35906070 PMCID: PMC9436012 DOI: 10.1523/jneurosci.0238-22.2022] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 07/06/2022] [Accepted: 07/14/2022] [Indexed: 11/21/2022] Open
Abstract
Dopamine (DA) is a critical regulator of striatal network activity and is essential for motor activation and reward-associated behaviors. Previous work has shown that DA is influenced by the reward value of food, as well as by hormonal factors that reguate food intake and energy expenditure. Changes in striatal DA signaling also have been linked to aberrant eating patterns. Here we test the effect of leptin, an adipocyte-derived hormone involved in feeding and energy homeostasis regulation, on striatal DA release and uptake. Immunohistochemical evaluation identified leptin receptor (LepR) expression throughout mouse striatum, including on striatal cholinergic interneurons (ChIs) and their extensive processes. Using fast-scan cyclic voltammetry (FSCV), we found that leptin causes a concentration-dependent increase in evoked extra-cellular DA concentration ([DA]o) in dorsal striatum (dStr) and nucleus accumbens (NAc) core and shell in male mouse striatal slices, and also an increase in the rate of DA uptake. Further, we found that leptin increases ChI excitability, and that the enhancing effect of leptin on evoked [DA]o is lost when nicotinic acetylcholine (ACh) receptors are antagonized or when examined in striatal slices from mice lacking ACh synthesis. Evaluation of signaling pathways underlying leptin's action revealed a requirement for intracellular Ca2+, and the involvement of different downstream pathways in dStr and NAc core versus NAc shell. These results provide the first evidence for dynamic regulation of DA release and uptake by leptin within brain motor and reward pathways, and highlight the involvement of ChIs in this process.SIGNIFICANCE STATEMENT Given the importance of striatal dopamine (DA) in reward, motivation, motor behavior and food intake, identifying the actions of metabolic hormones on DA release in striatal subregions should provide new insight into factors that influence DA-dependent motivated behaviors. We find that one of these hormones, leptin, boosts striatal DA release through a process involving striatal cholinergic interneurons (ChIs) and nicotinic acetylcholine (ACh) receptors. Moreover, we find that the intracellular cascades downstream from leptin receptor (LepR) activation that lead to enhanced DA release differ among striatal subregions. Thus, we not only show that leptin regulates DA release, but also identify characteristics of this process that could be harnessed to alter pathologic eating behaviors.
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Affiliation(s)
- Maria Mancini
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, New York 10016
- Neuroscience Institute, New York University Grossman School of Medicine, New York, New York 10016
| | - Jyoti C Patel
- Department of Neurosurgery, New York University Grossman School of Medicine, New York, New York 10016
| | - Alison H Affinati
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109
| | - Paul Witkovsky
- Department of Neurosurgery, New York University Grossman School of Medicine, New York, New York 10016
| | - Margaret E Rice
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, New York 10016
- Neuroscience Institute, New York University Grossman School of Medicine, New York, New York 10016
- Department of Neurosurgery, New York University Grossman School of Medicine, New York, New York 10016
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13
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Ortiz-Sanz C, Balantzategi U, Quintela-López T, Ruiz A, Luchena C, Zuazo-Ibarra J, Capetillo-Zarate E, Matute C, Zugaza JL, Alberdi E. Amyloid β / PKC-dependent alterations in NMDA receptor composition are detected in early stages of Alzheimer´s disease. Cell Death Dis 2022; 13:253. [PMID: 35306512 PMCID: PMC8934345 DOI: 10.1038/s41419-022-04687-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 02/07/2022] [Accepted: 02/24/2022] [Indexed: 12/15/2022]
Abstract
Amyloid beta (Aβ)-mediated synapse dysfunction is an early event in Alzheimer’s disease (AD) pathogenesis and previous studies suggest that NMDA receptor (NMDAR) dysregulation may contribute to these pathological effects. Although Aβ peptides impair NMDAR expression and activity, the mechanisms mediating these alterations in the early stages of AD are unclear. Here, we observed that NMDAR subunit NR2B and PSD-95 levels were aberrantly upregulated and correlated with Aβ42 load in human postsynaptic fractions of the prefrontal cortex in early stages of AD patients, as well as in the hippocampus of 3xTg-AD mice. Importantly, NR2B and PSD95 dysregulation was revealed by an increased expression of both proteins in Aβ-injected mouse hippocampi. In cultured neurons, Aβ oligomers increased the NR2B-containing NMDAR density in neuronal membranes and the NMDA-induced intracellular Ca2+ increase, in addition to colocalization in dendrites of NR2B subunit and PSD95. Mechanistically, Aβ oligomers required integrin β1 to promote synaptic location and function of NR2B-containing NMDARs and PSD95 by phosphorylation through classic PKCs. These results provide evidence that Aβ oligomers modify the contribution of NR2B to NMDAR composition and function in the early stages of AD through an integrin β1 and PKC-dependent pathway. These data reveal a novel role of Aβ oligomers in synaptic dysfunction that may be relevant to early-stage AD pathogenesis.
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Affiliation(s)
- Carolina Ortiz-Sanz
- Department of Neuroscience, University of Basque Country (UPV/EHU) and CIBERNED, Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Uxue Balantzategi
- Department of Neuroscience, University of Basque Country (UPV/EHU) and CIBERNED, Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Tania Quintela-López
- Department of Neuroscience, University of Basque Country (UPV/EHU) and CIBERNED, Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neuroscience, Physiology, & Pharmacology, University College London, London, UK
| | - Asier Ruiz
- Department of Neuroscience, University of Basque Country (UPV/EHU) and CIBERNED, Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Celia Luchena
- Department of Neuroscience, University of Basque Country (UPV/EHU) and CIBERNED, Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Jone Zuazo-Ibarra
- Department of Neuroscience, University of Basque Country (UPV/EHU) and CIBERNED, Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Estibaliz Capetillo-Zarate
- Department of Neuroscience, University of Basque Country (UPV/EHU) and CIBERNED, Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain.,IKERBASQUE Basque Foundation for Science, Bilbao, Spain
| | - Carlos Matute
- Department of Neuroscience, University of Basque Country (UPV/EHU) and CIBERNED, Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - José L Zugaza
- Achucarro Basque Center for Neuroscience, Leioa, Spain.,IKERBASQUE Basque Foundation for Science, Bilbao, Spain.,Department of Genetics, Physical Anthropology and Animal Physiology, UPV/EHU, Leioa, Spain
| | - Elena Alberdi
- Department of Neuroscience, University of Basque Country (UPV/EHU) and CIBERNED, Leioa, Spain. .,Achucarro Basque Center for Neuroscience, Leioa, Spain.
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14
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He C, Ji J, Zhao X, Lei Y, Li H, Hao Y, Zhang S, Zhang J, Liu C, Nie J, Niu Q. The Role of PKC in Regulating NMDARs in Aluminum-Induced Learning and Memory Impairment in Rats. Neurotox Res 2021; 39:2042-2055. [PMID: 34499332 DOI: 10.1007/s12640-021-00407-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/28/2021] [Accepted: 08/30/2021] [Indexed: 01/27/2023]
Abstract
Aluminum is a widespread environmental neurotoxicant that can induce Alzheimer's disease (AD)-like damage, such as neuronal injury and impairment of learning and memory. Several studies have shown that aluminum could reduce the synaptic plasticity, but its molecular mechanism remains unclear. In this study, rats were treated with aluminum maltol (Al(mal)3) to establish a toxic animal model and PMA was used to interfere with the expression of PKC. The Morris water maze and open field test were used to investigate the behavioral changes of the rats. Western blotting and RT-PCR were used to detect the expression levels of NMDAR subunits, PKC and CaMKII. The results showed that Al(mal)3 damaged learning and memory function and reduced anxiety in rats. During this process, the expression of PKC was downregulated and it inhibited the expression of NMDARs through the phosphorylation of CaMKII.
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Affiliation(s)
- Chanting He
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
- Key Lab of Environmental Hazard & Health of Shanxi Province, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
- Key Lab of Cellular Physiology of Education Ministry, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
- Department of Anatomy, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Jingjing Ji
- Fenyang College, Shanxi Medical University, Fenyang, 032200, Shanxi, China
| | - Xiaoyan Zhao
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Yang Lei
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Huan Li
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Yanxia Hao
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Shuhui Zhang
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Jingsi Zhang
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Chengjuan Liu
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Jisheng Nie
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China.
- Key Lab of Environmental Hazard & Health of Shanxi Province, Shanxi Medical University, Taiyuan, 030001, Shanxi, China.
- Key Lab of Cellular Physiology of Education Ministry, Shanxi Medical University, Taiyuan, 030001, Shanxi, China.
| | - Qiao Niu
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, 030001, Shanxi, China.
- Key Lab of Environmental Hazard & Health of Shanxi Province, Shanxi Medical University, Taiyuan, 030001, Shanxi, China.
- Key Lab of Cellular Physiology of Education Ministry, Shanxi Medical University, Taiyuan, 030001, Shanxi, China.
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15
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Gledhill LJ, Babey AM. Synthesis of the Mechanisms of Opioid Tolerance: Do We Still Say NO? Cell Mol Neurobiol 2021; 41:927-948. [PMID: 33704603 DOI: 10.1007/s10571-021-01065-8] [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: 12/20/2020] [Accepted: 02/12/2021] [Indexed: 10/21/2022]
Abstract
The use of morphine as a first-line agent for moderate-to-severe pain is limited by the development of analgesic tolerance. Initially opioid receptor desensitization in response to repeated stimulation, thought to underpin the establishment of tolerance, was linked to a compensatory increase in adenylate cyclase responsiveness. The subsequent demonstration of cross-talk between N-methyl-D-aspartate (NMDA) glutamate receptors and opioid receptors led to the recognition of a role for nitric oxide (NO), wherein blockade of NO synthesis could prevent tolerance developing. Investigations of the link between NO levels and opioid receptor desensitization implicated a number of events including kinase recruitment and peroxynitrite-mediated protein regulation. Recent experimental advances and the identification of new cellular constituents have expanded the potential signaling candidates to include unexpected, intermediary compounds not previously linked to this process such as zinc, histidine triad nucleotide-binding protein 1 (HINT1), micro-ribonucleic acid (mi-RNA) and regulator of G protein signaling Z (RGSZ). A further complication is a lack of consistency in the protocols used to create tolerance, with some using acute methods measured in minutes to hours and others using days. There is also an emphasis on the cellular changes that are extant only after tolerance has been established. Although a review of the literature demonstrates a lack of spatio-temporal detail, there still appears to be a pivotal role for nitric oxide, as well as both intracellular and intercellular cross-talk. The use of more consistent approaches to verify these underlying mechanism(s) could provide an avenue for targeted drug development to rescue opioid efficacy.
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Affiliation(s)
- Laura J Gledhill
- CURA Pharmacy, St. John of God Hospital, Bendigo, VIC, 3550, Australia
| | - Anna-Marie Babey
- Faculty of Medicine and Health, University of New England, Armidale, NSW, 2351, Australia.
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16
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Activation of voltage-gated sodium channels by BmK NT1 augments NMDA receptor function through Src family kinase signaling pathway in primary cerebellar granule cell cultures. Neuropharmacology 2020; 180:108291. [PMID: 32931812 DOI: 10.1016/j.neuropharm.2020.108291] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 08/23/2020] [Accepted: 08/26/2020] [Indexed: 12/29/2022]
Abstract
Voltage-gated sodium channels (VGSCs) are responsible for the generation and propagation of action potentials in excitable cells and are the molecular targets of an array of neurotoxins. BmK NT1, an α-scorpion toxin obtained from the scorpion Buthus martensii Karsch (BmK), produces neurotoxicity that is associated with extracellular Ca2+ influx through Na+-Ca2+ exchangers, N-methyl-d-aspartic acid (NMDA) receptors, and L-type Ca2+ channels in cultured cerebellar granule cells (CGCs). In the present study, we demonstrated that BmK NT1 triggered concentration-dependent release of excitatory neurotransmitters, glutamate and aspartate; both effects were eliminated by VGSC blocker, tetrodotoxin. More importantly, we demonstrated that a threshold concentration of BmK NT1 that produced marginal Ca2+ influx and neuronal death augmented glutamate-induced Ca2+ elevation and neuronal death in CGCs. BmK NT1-augmented glutamate-induced Ca2+ influx and neuronal death were suppressed by tetrodotoxin and MK-801 suggesting that the augmentation was through activation of VGSCs and NMDA receptors. Consistently, BmK NT1 also enhanced NMDA-induced Ca2+ influx. Further mechanistic investigations demonstrated that BmK NT1 increased the expression level of NMDA receptors on the plasma membrane and increased the phosphorylation level of NR2B at Tyr1472. Src family kinase inhibitor, 1-tert-butyl-3-(4-chlorophenyl)pyrazolo[3,4-d]pyrimidin-4-yl]amine (PP2), but not the inactive analogue, 4-amino-1-phenylpyrazolo[3,4-d]pyrimidine (PP3), eliminated BmK NT1-triggered NR2B phosphorylation, NMDA receptor trafficking, as well as BmK NT1-augmented NMDA Ca2+ response and neuronal death. Considered together, these data demonstrated that both presynaptic (excitatory amino acid release) and postsynaptic mechanisms (augmentation of NMDA receptor function) are critical for VGSC activation-induced neurotoxicity in primary CGC cultures.
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17
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Protein Kinase C Regulates ASIC1a Protein Expression and Channel Function via NF-kB Signaling Pathway. Mol Neurobiol 2020; 57:4754-4766. [PMID: 32783140 DOI: 10.1007/s12035-020-02056-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 08/03/2020] [Indexed: 10/23/2022]
Abstract
Tissue acidosis is a common feature in many pathological conditions. Activation of acid-sensing ion channel 1a (ASIC1a) plays a key role in acidosis-mediated neurotoxicity. Protein kinase C (PKC) activity has been proved to be associated with many physiological processes and pathological conditions; however, whether PKC activation regulates ASIC1a protein expression and channel function remains ill defined. In this study, we demonstrated that treatment with phorbol 12-myristate 13-acetate (PMA, a PKC activator) for 6 h significantly increased ASIC1a protein expression and ASIC currents in NS20Y cells, a neuronal cell line, and in primary cultured mouse cortical neurons. In contrast, treatment with Calphostin C (a nonselective PKC inhibitor) for 6 h or longer decreased ASIC1a protein expression and ASIC currents. Similar to Calphostin C, PKC α and βI inhibitor Go6976 exposure also reduced ASIC1a protein expression. The reduction in ASIC1a protein expression by PKC inhibition involves a change in ASIC1a protein degradation, which is mediated by ubiquitin-proteasome system (UPS)-dependent degradation pathway. In addition, we showed that PKC regulation of ASIC1a protein expression involves NF-κB signaling pathway. Consistent with their effects on ASIC1a protein expression and channel function, PKC inhibition protected NS20Y cells against acidosis-induced cytotoxicity, while PKC activation potentiated acidosis-induced cells injury. Together, these results indicate that ASIC1a protein expression and channel function are closely regulated by the activity of protein kinase C and its downstream signaling pathway(s).
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18
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Kumar A. Calcium Signaling During Brain Aging and Its Influence on the Hippocampal Synaptic Plasticity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:985-1012. [PMID: 31646542 DOI: 10.1007/978-3-030-12457-1_39] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Calcium (Ca2+) ions are highly versatile intracellular signaling molecules and are universal second messenger for regulating a variety of cellular and physiological functions including synaptic plasticity. Ca2+ homeostasis in the central nervous system endures subtle dysregulation with advancing age. Research has provided abundant evidence that brain aging is associated with altered neuronal Ca2+ regulation and synaptic plasticity mechanisms. Much of the work has focused on the hippocampus, a brain region critically involved in learning and memory, which is particularly susceptible to dysfunction during aging. The current chapter takes a specific perspective, assessing various Ca2+ sources and the influence of aging on Ca2+ sources and synaptic plasticity in the hippocampus. Integrating the knowledge of the complexity of age-related alterations in neuronal Ca2+ signaling and synaptic plasticity mechanisms will positively shape the development of highly effective therapeutics to treat brain disorders including cognitive impairment associated with aging and neurodegenerative disease.
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Affiliation(s)
- Ashok Kumar
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
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19
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Epileptiform activity promotes decreasing of Ca 2+ conductivity of NMDARs, AMPARs, KARs, and voltage-gated calcium channels in Mg 2+-free model. Epilepsy Res 2019; 158:106224. [PMID: 31698280 DOI: 10.1016/j.eplepsyres.2019.106224] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 10/01/2019] [Accepted: 10/22/2019] [Indexed: 02/06/2023]
Abstract
NMDA, AMPA, and kainate receptors are the principal excitatory receptors in the brain. These receptors have been considered as the main targets in the treatment of epilepsy in recent years. This work aimed to determine how the Ca2+ conductivity of ionotropic glutamate receptors and voltage-gated Ca2+ channels changes in an in vitro model of epilepsy. For induction of epileptiform activity, hippocampal neurons were exposed to Mg2+-free medium. It has been shown that removal of Mg2+ from the medium not only removes the block from the NMDA receptors but also stimulates the release of glutamate in a way that is independent of the NMDA receptors. Under these conditions, the structure of the bursts significantly differs from the spontaneous bursts arising in mature hippocampal cultures. We have demonstrated that the frequency and amplitude of Mg2+-free medium-induced Ca2+ oscillations decrease after the 60-min exposure. Besides, the Ca2+ conductivity of ionotropic glutamate receptors and voltage-gated calcium channels significantly reduces. Thus, the decrease of Ca2+ conductivity can be considered as one of the mechanisms of adaptation during epilepsy.
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20
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Carrano N, Samaddar T, Brunialti E, Franchini L, Marcello E, Ciana P, Mauceri D, Di Luca M, Gardoni F. The Synaptonuclear Messenger RNF10 Acts as an Architect of Neuronal Morphology. Mol Neurobiol 2019; 56:7583-7593. [DOI: 10.1007/s12035-019-1631-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 04/29/2019] [Indexed: 10/26/2022]
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21
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Chandran R, Kumar M, Kesavan L, Jacob RS, Gunasekaran S, Lakshmi S, Sadasivan C, Omkumar R. Cellular calcium signaling in the aging brain. J Chem Neuroanat 2019; 95:95-114. [DOI: 10.1016/j.jchemneu.2017.11.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 09/03/2017] [Accepted: 11/07/2017] [Indexed: 12/21/2022]
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22
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Sapkota K, Dore K, Tang K, Irvine M, Fang G, Burnell ES, Malinow R, Jane DE, Monaghan DT. The NMDA receptor intracellular C-terminal domains reciprocally interact with allosteric modulators. Biochem Pharmacol 2018; 159:140-153. [PMID: 30503374 DOI: 10.1016/j.bcp.2018.11.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 11/28/2018] [Indexed: 11/27/2022]
Abstract
N-methyl-d-aspartate receptors (NMDARs) have multiple prominent roles in CNS function but their excessive or insufficient activity contributes to neuropathological/psychiatric disorders. Consequently, a variety of positive and negative allosteric modulators (PAMs and NAMs, respectively) have recently been developed. Although these modulators bind to extracellular domains, in the present report we find that the NMDAR's intracellular C-terminal domains (CTDs) significantly influence PAM/NAM activity. GluN2 CTD deletion robustly affected NAM and PAM activity with both enhancing and inhibiting effects that were compound-specific and NMDAR subunit-specific. In three cases, individual PAMs became NAMs at specific GluN2-truncated receptors. In contrast to GluN2, GluN1 CTD removal only reduced PAM activity of UBP684 and CIQ, and did not affect NAM activity. Consistent with these findings, agents altering phosphorylation state or intracellular calcium levels displayed receptor-specific and compound-specific effects on PAM activity. It is possible that the GluN2's M4 domain transmits intracellular modulatory signals from the CTD to the M1/M4 channel gating machinery and that this site is a point of convergence in the direct or indirect actions of several PAMs/NAMs thus rendering them sensitive to CTD status. Thus, allosteric modulators are likely to have a marked and varied sensitivity to post-translational modifications, protein-protein associations, and intracellular ions. The interaction between PAM activity and NMDAR CTDs appears reciprocal. GluN1 CTD-deletion eliminated UBP684, but not pregnenolone sulfate (PS), PAM activity. And, in the absence of agonists, UBP684, but not PS, was able to promote movement of fluorescently-tagged GluN1-CTDs. Thus, it may be possible to pharmacologically target NMDAR metabotropic activity in the absence of channel activation.
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Affiliation(s)
- Kiran Sapkota
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198-5800, USA
| | - Kim Dore
- Center for Neural Circuits and Behavior, Department of Neuroscience and Section for Neurobiology, Division of Biology, University of California at San Diego, San Diego, CA 92093-0634, USA
| | - Kang Tang
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198-5800, USA
| | - Mark Irvine
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences Building, University Walk, University of Bristol, Bristol BS8 1TD, UK
| | - Guangyu Fang
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences Building, University Walk, University of Bristol, Bristol BS8 1TD, UK
| | - Erica S Burnell
- School of Chemistry, National University of Ireland Galway, Galway H91TK33, Ireland
| | - Roberto Malinow
- Center for Neural Circuits and Behavior, Department of Neuroscience and Section for Neurobiology, Division of Biology, University of California at San Diego, San Diego, CA 92093-0634, USA
| | - David E Jane
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences Building, University Walk, University of Bristol, Bristol BS8 1TD, UK
| | - Daniel T Monaghan
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198-5800, USA.
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23
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Kumar A, Foster TC. Alteration in NMDA Receptor Mediated Glutamatergic Neurotransmission in the Hippocampus During Senescence. Neurochem Res 2018; 44:38-48. [PMID: 30209673 DOI: 10.1007/s11064-018-2634-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 09/07/2018] [Accepted: 09/08/2018] [Indexed: 12/17/2022]
Abstract
Glutamate is the primary excitatory neurotransmitter in neurons and glia. N-methyl-D-aspartate (NMDA), α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), and kainate receptors are major ionotropic glutamate receptors. Glutamatergic neurotransmission is strongly linked with Ca2+ homeostasis. Research has provided ample evidence that brain aging is associated with altered glutamatergic neurotransmission and Ca2+ dysregulation. Much of the work has focused on the hippocampus, a brain region critically involved in learning and memory, which is particularly susceptible to dysfunction during senescence. The current review examines Ca2+ regulation with a focus on the NMDA receptors in the hippocampus. Integrating the knowledge of the complexity of age-related alterations in Ca2+ homeostasis and NMDA receptor-mediated glutamatergic neurotransmission will positively shape the development of highly effective therapeutics to treat brain disorders including cognitive impairment.
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Affiliation(s)
- Ashok Kumar
- Department of Neuroscience, McKnight Brain Institute, University of Florida, PO Box 100244, Gainesville, FL, 32610-0244, USA.
| | - Thomas C Foster
- Department of Neuroscience, McKnight Brain Institute, University of Florida, PO Box 100244, Gainesville, FL, 32610-0244, USA.
- Genetics and Genomics Program, University of Florida, Gainesville, FL, 32611, USA.
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24
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Ma Q, Yang J, Milner TA, Vonsattel JPG, Palko ME, Tessarollo L, Hempstead BL. SorCS2-mediated NR2A trafficking regulates motor deficits in Huntington's disease. JCI Insight 2017; 2:88995. [PMID: 28469074 PMCID: PMC5414556 DOI: 10.1172/jci.insight.88995] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 03/30/2017] [Indexed: 12/14/2022] Open
Abstract
Motor dysfunction is a prominent and disabling feature of Huntington's disease (HD), but the molecular mechanisms that dictate its onset and progression are unknown. The N-methyl-D-aspartate receptor 2A (NR2A) subunit regulates motor skill development and synaptic plasticity in medium spiny neurons (MSNs) of the striatum, cells that are most severely impacted by HD. Here, we document reduced NR2A receptor subunits on the dendritic membranes and at the synapses of MSNs in zQ175 mice that model HD. We identify that SorCS2, a vacuolar protein sorting 10 protein-domain (VPS10P-domain) receptor, interacts with VPS35, a core component of retromer, thereby regulating surface trafficking of NR2A in MSNs. In the zQ175 striatum, SorCS2 is markedly decreased in an age- and allele-dependent manner. Notably, SorCS2 selectively interacts with mutant huntingtin (mtHTT), but not WT huntingtin (wtHTT), and is mislocalized to perinuclear clusters in striatal neurons of human HD patients and zQ175 mice. Genetic deficiency of SorCS2 accelerates the onset and exacerbates the motor coordination deficit of zQ175 mice. Together, our results identify SorCS2 as an interacting protein of mtHTT and demonstrate that impaired SorCS2-mediated NR2A subunit trafficking to dendritic surface of MSNs is, to our knowledge, a novel mechanism contributing to motor coordination deficits of HD.
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Affiliation(s)
- Qian Ma
- Graduate Program of Neuroscience
| | - Jianmin Yang
- Department of Medicine, Weill Cornell Medicine, New York, New York, USA.,Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, People's Republic of China
| | - Teresa A Milner
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York, USA.,Laboratory of Neuroendocrinology, The Rockefeller University, New York, New York, USA
| | - Jean-Paul G Vonsattel
- The New York Brain Bank/Taub Institute Columbia University, Children's Hospital, New York, New York, USA
| | - Mary Ellen Palko
- Mouse Cancer Genetics Program, Center for Cancer Research, NCI, Frederick, Maryland, USA
| | - Lino Tessarollo
- Mouse Cancer Genetics Program, Center for Cancer Research, NCI, Frederick, Maryland, USA
| | - Barbara L Hempstead
- Department of Medicine, Weill Cornell Medicine, New York, New York, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York, USA
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25
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Xu J, Kurup P, Nairn AC, Lombroso PJ. Synaptic NMDA Receptor Activation Induces Ubiquitination and Degradation of STEP 61. Mol Neurobiol 2017; 55:3096-3111. [PMID: 28466270 DOI: 10.1007/s12035-017-0555-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 04/12/2017] [Indexed: 01/25/2023]
Abstract
NMDA receptor signaling is critical for the development of synaptic plasticity, learning, and memory, and dysregulation of NMDAR signaling is implicated in a number of neurological disorders including schizophrenia (SZ). Previous work has demonstrated that the STriatal-Enriched protein tyrosine Phosphatase 61 kDa (STEP61) is elevated in human SZ postmortem cortical samples and after administration of psychotomimetics to cultures or mice. Here, we report that activation of synaptic NMDAR by bicuculline or D-serine results in the ubiquitination and proteasomal degradation of STEP61, and increased surface localization of GluN1/GluN2B receptors. Moreover, bicuculline or D-serine treatments rescue the motor and cognitive deficits in MK-801-treated mice and reduce STEP61 in mouse frontal cortex. These results suggest that STEP61 may contribute to the therapeutic effects of D-serine.
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Affiliation(s)
- Jian Xu
- Child Study Center, Yale University School of Medicine, New Haven, USA
| | - Pradeep Kurup
- Child Study Center, Yale University School of Medicine, New Haven, USA
| | - Angus C Nairn
- Department of Psychiatry, Yale University School of Medicine, New Haven, USA
| | - Paul J Lombroso
- Child Study Center, Yale University School of Medicine, New Haven, USA. .,Department of Psychiatry, Yale University School of Medicine, New Haven, USA. .,Department of Neurobiology, Yale University School of Medicine, New Haven, USA.
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26
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Furlong TM, Duncan JR, Corbit LH, Rae CD, Rowlands BD, Maher AD, Nasrallah FA, Milligan CJ, Petrou S, Lawrence AJ, Balleine BW. Toluene inhalation in adolescent rats reduces flexible behaviour in adulthood and alters glutamatergic and GABAergic signalling. J Neurochem 2016; 139:806-822. [PMID: 27696399 DOI: 10.1111/jnc.13858] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 09/15/2016] [Accepted: 09/18/2016] [Indexed: 12/24/2022]
Abstract
Toluene is a commonly abused inhalant that is easily accessible to adolescents. Despite the increasing incidence of use, our understanding of its long-term impact remains limited. Here, we used a range of techniques to examine the acute and chronic effects of toluene exposure on glutameteric and GABAergic function, and on indices of psychological function in adult rats after adolescent exposure. Metabolomics conducted on cortical tissue established that acute exposure to toluene produces alterations in cellular metabolism indicative of a glutamatergic and GABAergic profile. Similarly, in vitro electrophysiology in Xenopus oocytes found that acute toluene exposure reduced NMDA receptor signalling. Finally, in an adolescent rodent model of chronic intermittent exposure to toluene (10 000 ppm), we found that, while toluene exposure did not affect initial learning, it induced a deficit in updating that learning when response-outcome relationships were reversed or degraded in an instrumental conditioning paradigm. There were also group differences when more effort was required to obtain the reward; toluene-exposed animals were less sensitive to progressive ratio schedules and to delayed discounting. These behavioural deficits were accompanied by changes in subunit expression of both NMDA and GABA receptors in adulthood, up to 10 weeks after the final exposure to toluene in the hippocampus, prefrontal cortex and ventromedial striatum; regions with recognized roles in behavioural flexibility and decision-making. Collectively, our data suggest that exposure to toluene is sufficient to induce adaptive changes in glutamatergic and GABAergic systems and in adaptive behaviour that may underlie the deficits observed following adolescent inhalant abuse, including susceptibility to further drug-use.
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Affiliation(s)
- Teri M Furlong
- Brain & Mind Centre, University of Sydney, Sydney, New South Wales, Australia.,School of Psychology, University of Sydney, Sydney, New South Wales, Australia
| | - Jhodie R Duncan
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia.,Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia
| | - Laura H Corbit
- School of Psychology, University of Sydney, Sydney, New South Wales, Australia
| | - Caroline D Rae
- Neuroscience Research Australia, Randwick, New South Wales, Australia.,School of Medical Sciences, University of NSW, Kensington, New South Wales, Australia
| | - Benjamin D Rowlands
- Neuroscience Research Australia, Randwick, New South Wales, Australia.,School of Medical Sciences, University of NSW, Kensington, New South Wales, Australia
| | - Anthony D Maher
- Neuroscience Research Australia, Randwick, New South Wales, Australia
| | | | - Carol J Milligan
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Steven Petrou
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Andrew J Lawrence
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Bernard W Balleine
- Brain & Mind Centre, University of Sydney, Sydney, New South Wales, Australia.,School of Psychology, University of NSW, Kensington, New South Wales, Australia
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27
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Sun Y, Zhan L, Cheng X, Zhang L, Hu J, Gao Z. The Regulation of GluN2A by Endogenous and Exogenous Regulators in the Central Nervous System. Cell Mol Neurobiol 2016; 37:389-403. [PMID: 27255970 DOI: 10.1007/s10571-016-0388-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 05/25/2016] [Indexed: 12/25/2022]
Abstract
The NMDA receptor is the most widely studied ionotropic glutamate receptor, and it is central to many physiological and pathophysiological processes in the central nervous system. GluN2A is one of the two main types of GluN2 NMDA receptor subunits in the forebrain. The proper activity of GluN2A is important to brain function, as the abnormal regulation of GluN2A may induce some neuropsychiatric disorders. This review will examine the regulation of GluN2A by endogenous and exogenous regulators in the central nervous system.
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Affiliation(s)
- Yongjun Sun
- Department of Pharmacy, Hebei University of Science and Technology, Yuhua East Road 70, Shijiazhuang, 050018, People's Republic of China.,Hebei Research Center of Pharmaceutical and Chemical Engineering, Hebei University of Science and Technology, Shijiazhuang, 050018, People's Republic of China
| | - Liying Zhan
- Department of Pharmacy, Hebei University of Science and Technology, Yuhua East Road 70, Shijiazhuang, 050018, People's Republic of China
| | - Xiaokun Cheng
- North China Pharmaceutical Group New Drug Research and Development Co., Ltd, Shijiazhuang, 050015, People's Republic of China
| | - Linan Zhang
- Department of Pathophysiology, Hebei Medical University, Shijiazhuang, 050017, People's Republic of China
| | - Jie Hu
- School of Nursing, Hebei Medical University, Shijiazhuang, 050017, People's Republic of China
| | - Zibin Gao
- Department of Pharmacy, Hebei University of Science and Technology, Yuhua East Road 70, Shijiazhuang, 050018, People's Republic of China. .,Hebei Research Center of Pharmaceutical and Chemical Engineering, Hebei University of Science and Technology, Shijiazhuang, 050018, People's Republic of China. .,State Key Laboratory Breeding Base-Hebei Province Key Laboratory of Molecular Chemistry for Drug, Shijiazhuang, 050018, People's Republic of China.
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28
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Enzymatic Depletion of the Polysialic Acid Moiety Associated with the Neural Cell Adhesion Molecule Inhibits Antidepressant Efficacy. Neuropsychopharmacology 2016; 41:1670-80. [PMID: 26530284 PMCID: PMC4832030 DOI: 10.1038/npp.2015.337] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 10/04/2015] [Accepted: 10/27/2015] [Indexed: 01/01/2023]
Abstract
Antidepressant drugs are too often ineffective, the exact mechanism of efficacy is still ambiguous, and there has been a paucity of novel targets for pharmacotherapy. In an attempt to understand the pathogenesis of depression and subsequently develop more efficacious antidepressant drugs, multiple theories have been proposed, including the modulation of neurotransmission, the upregulation of neurogenesis and neurotrophic factors, normalizing hypothalamic-pituitary-adrenal reactivity, and the reduction of neuroinflammation; all of which have supporting lines of evidence. Therefore, an ideal molecular target for novel pharmaceutical intervention would function at the confluence of these theories. The polysialylated form of the neural cell adhesion molecule (PSA-NCAM) functions broadly, serving to mediate synaptic plasticity, neurogenesis, neurotrophic factor signaling, and inflammatory signaling throughout the brain; all of which are associated with the pathophysiology and treatment of depression. Moreover, the expression of PSA-NCAM is reduced by depression, and conversely enhanced by antidepressant treatment, particularly within the hippocampus. Here we demonstrate that selectively cleaving the polysialic acid moiety, using the bacteriophage-derived enzyme endoneuraminidase N, completely inhibits the antidepressant efficacy of the selective-serotonin reuptake inhibitor fluoxetine (FLX) in a chronic unpredictable stress model of depression. We also observe a corresponding attenuation of FLX-induced hippocampal neuroplasticity, including decreased hippocampal neurogenesis, synaptic density, and neural activation. These data indicate that PSA-NCAM-mediated neuroplasticity is necessary for antidepressant action; therefore PSA-NCAM represents an interesting, and novel, target for pharmacotherapy.
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29
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Presynaptic serotonin 2A receptors modulate thalamocortical plasticity and associative learning. Proc Natl Acad Sci U S A 2016; 113:E1382-91. [PMID: 26903620 DOI: 10.1073/pnas.1525586113] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Higher-level cognitive processes strongly depend on a complex interplay between mediodorsal thalamus nuclei and the prefrontal cortex (PFC). Alteration of thalamofrontal connectivity has been involved in cognitive deficits of schizophrenia. Prefrontal serotonin (5-HT)2A receptors play an essential role in cortical network activity, but the mechanism underlying their modulation of glutamatergic transmission and plasticity at thalamocortical synapses remains largely unexplored. Here, we show that 5-HT2A receptor activation enhances NMDA transmission and gates the induction of temporal-dependent plasticity mediated by NMDA receptors at thalamocortical synapses in acute PFC slices. Expressing 5-HT2A receptors in the mediodorsal thalamus (presynaptic site) of 5-HT2A receptor-deficient mice, but not in the PFC (postsynaptic site), using a viral gene-delivery approach, rescued the otherwise absent potentiation of NMDA transmission, induction of temporal plasticity, and deficit in associative memory. These results provide, to our knowledge, the first physiological evidence of a role of presynaptic 5-HT2A receptors located at thalamocortical synapses in the control of thalamofrontal connectivity and the associated cognitive functions.
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30
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Kumar A. NMDA Receptor Function During Senescence: Implication on Cognitive Performance. Front Neurosci 2015; 9:473. [PMID: 26732087 PMCID: PMC4679982 DOI: 10.3389/fnins.2015.00473] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Accepted: 11/25/2015] [Indexed: 12/13/2022] Open
Abstract
N-methyl-D-aspartate (NMDA) receptors, a family of L-glutamate receptors, play an important role in learning and memory, and are critical for spatial memory. These receptors are tetrameric ion channels composed of a family of related subunits. One of the hallmarks of the aging human population is a decline in cognitive function; studies in the past couple of years have demonstrated deterioration in NMDA receptor subunit expression and function with advancing age. However, a direct relationship between impaired memory function and a decline in NMDA receptors is still ambiguous. Recent studies indicate a link between an age-associated NMDA receptor hypofunction and memory impairment and provide evidence that age-associated enhanced oxidative stress might be contributing to the alterations associated with senescence. However, clear evidence is still deficient in demonstrating the underlying mechanisms and a relationship between age-associated impaired cognitive faculties and NMDA receptor hypofunction. The current review intends to present an overview of the research findings regarding changes in expression of various NMDA receptor subunits and deficits in NMDA receptor function during senescence and its implication in age-associated impaired hippocampal-dependent memory function.
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Affiliation(s)
- Ashok Kumar
- Department of Neuroscience, Evelyn F. and William L. McKnight Brain Institute, University of Florida Gainesville, FL, USA
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31
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Petitjean H, Pawlowski SA, Fraine SL, Sharif B, Hamad D, Fatima T, Berg J, Brown CM, Jan LY, Ribeiro-da-Silva A, Braz JM, Basbaum AI, Sharif-Naeini R. Dorsal Horn Parvalbumin Neurons Are Gate-Keepers of Touch-Evoked Pain after Nerve Injury. Cell Rep 2015; 13:1246-1257. [PMID: 26527000 PMCID: PMC6038918 DOI: 10.1016/j.celrep.2015.09.080] [Citation(s) in RCA: 213] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 09/04/2015] [Accepted: 09/25/2015] [Indexed: 01/01/2023] Open
Abstract
Neuropathic pain is a chronic debilitating disease that results from nerve damage, persists long after the injury has subsided, and is characterized by spontaneous pain and mechanical hypersensitivity. Although loss of inhibitory tone in the dorsal horn of the spinal cord is a major contributor to neuropathic pain, the molecular and cellular mechanisms underlying this disinhibition are unclear. Here, we combined pharmacogenetic activation and selective ablation approaches in mice to define the contribution of spinal cord parvalbumin (PV)-expressing inhibitory interneurons in naive and neuropathic pain conditions. Ablating PV neurons in naive mice produce neuropathic pain-like mechanical allodynia via disinhibition of PKCγ excitatory interneurons. Conversely, activating PV neurons in nerve-injured mice alleviates mechanical hypersensitivity. These findings indicate that PV interneurons are modality-specific filters that gate mechanical but not thermal inputs to the dorsal horn and that increasing PV inter-neuron activity can ameliorate the mechanical hypersensitivity that develops following nerve injury.
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Affiliation(s)
- Hugues Petitjean
- Department of Physiology and Cell Information Systems Group, McGill University, Montreal, H3G0B1 QC, Canada
| | | | - Steven Li Fraine
- Department of Physiology and Cell Information Systems Group, McGill University, Montreal, H3G0B1 QC, Canada
| | - Behrang Sharif
- Department of Physiology and Cell Information Systems Group, McGill University, Montreal, H3G0B1 QC, Canada
| | - Doulia Hamad
- Department of Physiology and Cell Information Systems Group, McGill University, Montreal, H3G0B1 QC, Canada
| | - Tarheen Fatima
- Department of Physiology and Cell Information Systems Group, McGill University, Montreal, H3G0B1 QC, Canada
| | - Jim Berg
- Departments of Physiology and Biochemistry, Howard Hughes Medical Institute, University of California, San Francisco, 1550 4th Street, RH-490D, San Francisco, CA 94158, USA
| | - Claire M Brown
- Department of Physiology and Cell Information Systems Group, McGill University, Montreal, H3G0B1 QC, Canada; Advanced BioImaging Facility, McGill University, H3G0B1 QC, Canada
| | - Lily-Yeh Jan
- Departments of Physiology and Biochemistry, Howard Hughes Medical Institute, University of California, San Francisco, 1550 4th Street, RH-490D, San Francisco, CA 94158, USA
| | - Alfredo Ribeiro-da-Silva
- Department of Pharmacology and Therapeutics, McGill University, H3G1Y6 QC, Canada; Department of Anatomy and Cell Biology, McGill University, H3A0C7 QC, Canada
| | - Joao M Braz
- Department of Anatomy, University of California, San Francisco, 1550 4th Street, RH-348E, San Francisco, CA 94158, USA
| | - Allan I Basbaum
- Department of Anatomy, University of California, San Francisco, 1550 4th Street, RH-348E, San Francisco, CA 94158, USA
| | - Reza Sharif-Naeini
- Department of Physiology and Cell Information Systems Group, McGill University, Montreal, H3G0B1 QC, Canada.
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32
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The Deleterious Effects of Oxidative and Nitrosative Stress on Palmitoylation, Membrane Lipid Rafts and Lipid-Based Cellular Signalling: New Drug Targets in Neuroimmune Disorders. Mol Neurobiol 2015; 53:4638-58. [PMID: 26310971 DOI: 10.1007/s12035-015-9392-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Accepted: 08/11/2015] [Indexed: 12/18/2022]
Abstract
Oxidative and nitrosative stress (O&NS) is causatively implicated in the pathogenesis of Alzheimer's and Parkinson's disease, multiple sclerosis, chronic fatigue syndrome, schizophrenia and depression. Many of the consequences stemming from O&NS, including damage to proteins, lipids and DNA, are well known, whereas the effects of O&NS on lipoprotein-based cellular signalling involving palmitoylation and plasma membrane lipid rafts are less well documented. The aim of this narrative review is to discuss the mechanisms involved in lipid-based signalling, including palmitoylation, membrane/lipid raft (MLR) and n-3 polyunsaturated fatty acid (PUFA) functions, the effects of O&NS processes on these processes and their role in the abovementioned diseases. S-palmitoylation is a post-translational modification, which regulates protein trafficking and association with the plasma membrane, protein subcellular location and functions. Palmitoylation and MRLs play a key role in neuronal functions, including glutamatergic neurotransmission, and immune-inflammatory responses. Palmitoylation, MLRs and n-3 PUFAs are vulnerable to the corruptive effects of O&NS. Chronic O&NS inhibits palmitoylation and causes profound changes in lipid membrane composition, e.g. n-3 PUFA depletion, increased membrane permeability and reduced fluidity, which together lead to disorders in intracellular signal transduction, receptor dysfunction and increased neurotoxicity. Disruption of lipid-based signalling is a source of the neuroimmune disorders involved in the pathophysiology of the abovementioned diseases. n-3 PUFA supplementation is a rational therapeutic approach targeting disruptions in lipid-based signalling.
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33
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Loss of F-box only protein 2 (Fbxo2) disrupts levels and localization of select NMDA receptor subunits, and promotes aberrant synaptic connectivity. J Neurosci 2015; 35:6165-78. [PMID: 25878288 DOI: 10.1523/jneurosci.3013-14.2015] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
NMDA receptors (NMDARs) play an essential role in some forms of synaptic plasticity, learning, and memory. Therefore, these receptors are highly regulated with respect to their localization, activation, and abundance both within and on the surface of mammalian neurons. Fundamental questions remain, however, regarding how this complex regulation is achieved. Using cell-based models and F-box Only Protein 2 (Fbxo2) knock-out mice, we found that the ubiquitin ligase substrate adaptor protein Fbxo2, previously reported to facilitate the degradation of the NMDAR subunit GluN1 in vitro, also functions to regulate GluN1 and GluN2A subunit levels in the adult mouse brain. In contrast, GluN2B subunit levels are not affected by the loss of Fbxo2. The loss of Fbxo2 results in greater surface localization of GluN1 and GluN2A, together with increases in the synaptic markers PSD-95 and Vglut1. These synaptic changes do not manifest as neurophysiological differences or alterations in dendritic spine density in Fbxo2 knock-out mice, but result instead in increased axo-dendritic shaft synapses. Together, these findings suggest that Fbxo2 controls the abundance and localization of specific NMDAR subunits in the brain and may influence synapse formation and maintenance.
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34
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Hendriksen RG, Hoogland G, Schipper S, Hendriksen JG, Vles JS, Aalbers MW. A possible role of dystrophin in neuronal excitability: A review of the current literature. Neurosci Biobehav Rev 2015; 51:255-62. [DOI: 10.1016/j.neubiorev.2015.01.023] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Revised: 01/18/2015] [Accepted: 01/31/2015] [Indexed: 10/24/2022]
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35
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Li C, Lu Q, Huang P, Fu T, Li C, Guo L, Xu X. Activity-dependent downregulation of M-Type (Kv7) K⁺ channels surface expression requires the activation of iGluRs/Ca²⁺/PKC signaling pathway in hippocampal neuron. Neuropharmacology 2015; 95:154-67. [PMID: 25796298 DOI: 10.1016/j.neuropharm.2015.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Revised: 02/26/2015] [Accepted: 03/09/2015] [Indexed: 10/23/2022]
Abstract
M-type (Kv7) K(+) channels, encoded by KCNQ2-KCNQ5 genes, play a pivotal role in controlling neuronal excitability. However, precisely how neuronal activity regulates Kv7 channel translocation has not yet been fully defined. Here we reported activity-dependent changes in Kv7 channel subunits Kv7.2 and Kv7.3 surface expression by glutamate (glu). In the present study, we found that treatment with glutamate rapidly caused a specific decrease in M-current as well as Kv7 channel surface expression in primary cultured hippocampal neurons. The glutamate effects were mimicked by NMDA and AMPA. The glutamate effects on Kv7 channels were partially attenuated by pre-treatment of NMDA receptors antagonist d,l-APV or AMPA-KA receptors antagonist CNQX. The signal required Ca(2+) influx through L-type Ca(2+) channel and intracellular Ca(2+) elevations. PKC activation was involved in the glutamate-induced reduction of Kv7 channel surface expression. Moreover, a significant reduction of Kv7 channel surface expression occurred following glycine-induced "chem"-LTP in vitro and hippocampus-dependent behavioral learning training in vivo. These results demonstrated that activity-dependent reduction of Kv7 channel surface expression through activation of ionotropic glutamate receptors (iGluRs)/Ca(2+)/PKC signaling pathway might be an important molecular mechanism for regulation of neuronal excitability and synaptic plasticity.
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Affiliation(s)
- Cai Li
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Qing Lu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China; The Institute of Brain Research, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Pengcheng Huang
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Tianli Fu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Changjun Li
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Lianjun Guo
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China; The Institute of Brain Research, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xulin Xu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China; The Institute of Brain Research, Huazhong University of Science and Technology, Wuhan 430030, China.
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36
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Chen LJ, Wang YJ, Chen JR, Tseng GF. NMDA receptor triggered molecular cascade underlies compression-induced rapid dendritic spine plasticity in cortical neurons. Exp Neurol 2015; 266:86-98. [PMID: 25708984 DOI: 10.1016/j.expneurol.2015.02.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Revised: 12/05/2014] [Accepted: 02/09/2015] [Indexed: 10/24/2022]
Abstract
Compression causes the reduction of dendritic spines of underlying adult cortical pyramidal neurons but the mechanisms remain at large. Using a rat epidural cerebral compression model, dendritic spines on the more superficial-lying layer III pyramidal neurons were found quickly reduced in 12h, while those on the deep-located layer V pyramidal neurons were reduced slightly later, starting 1day following compression. No change in the synaptic vesicle markers synaptophysin and vesicular glutamate transporter 1 suggest no change in afferents. Postsynaptically, N-methyl-d-aspartate (NMDA) receptor trafficking to synaptic membrane was detected in 10min and lasting to 1day after compression. Translocation of calcineurin to synapses and enhancement of its enzymatic activity were detected within 10min as well. These suggest that compression rapidly activated NMDA receptors to increase postsynaptic calcium, which then activated the phosphatase calcineurin. In line with this, dephosphorylation and activation of the actin severing protein cofilin, and the consequent depolymerization of actin were all identified in the compressed cortex within matching time frames. Antagonizing NMDA receptors with MK801 before compression prevented this cascade of events, including NR1 mobilization, calcineurin activation and actin depolymerization, in the affected cortex. Morphologically, MK801 pretreatment prevented the loss of dendritic spines on the compressed cortical pyramidal neurons as well. In short, we demonstrated, for the first time, mechanisms underlying the rapid compression-induced cortical neuronal dendritic spine plasticity. In addition, the mechanical force of compression appears to activate NMDA receptors to initiate a rapid postsynaptic molecular cascade to trim dendritic spines on the compressed cortical pyramidal neurons within half a day.
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Affiliation(s)
- Li-Jin Chen
- Department of Anatomy, College of Medicine, Tzu-Chi University, Hualien, Taiwan
| | - Yueh-Jan Wang
- Department of Anatomy, College of Medicine, Tzu-Chi University, Hualien, Taiwan
| | - Jeng-Rung Chen
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung-Hsing University, Taichung, Taiwan
| | - Guo-Fang Tseng
- Department of Anatomy, College of Medicine, Tzu-Chi University, Hualien, Taiwan.
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37
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Shang XL, Wang QB, Liu XP, Yao XQ, Cao FY, Wang Q, Zhang JY, Wang JZ, Liu GP. Fluorocitrate induced the alterations of memory-related proteins and tau hyperphosphorylation in SD rats. Neurosci Lett 2014; 584:230-5. [PMID: 25449869 DOI: 10.1016/j.neulet.2014.10.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 10/03/2014] [Accepted: 10/20/2014] [Indexed: 01/22/2023]
Abstract
Astrocytes provide structural, metabolic and trophic supports for neurons. However, there are no direct evidences whether astrocytes involve in the regulation of synaptic proteins expression and tau phosphorylation until now. Here, we injected 1 nmol fluorocitrate (FC), which preferentially taken up by astrocytes and results in reversible inhibition of the astrocytic tricarboxylic acid cycle, into the left lateral ventricle of the brain in the SD rats for 1h, and found that FC treatment decreased several memory-related proteins levels, such as AMPA receptor GluR1/2, postsynaptic density protein 93/95, Arc and phosphorylated cAMP response element binding proteins, while increased synaptophysin and synapsin I levels in the hippocampus. FC treatment also increased the levels of phosphorylated tau at multiple Alzheimer-related phosphorylation sites, as well as activation of glycogen synthase kinase-3β and inactivation of protein phosphatase-2A. Similar effects were also observed in the primary hippocampal neurons, which were cultured with the conditioned media from FC-treatment primary astrocytes. Our data suggest that astrocytes regulate neuronal tau phosphorylation and several synaptic proteins expression.
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Affiliation(s)
- Xiao-Ling Shang
- Department of Pathophysiology, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Key Laboratory of Ministry of Education for Neurological Disorders, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China
| | - Quan-Bao Wang
- Department of Neurology, The People's Hospital of Linfen City, Shangdong Province 276000, PR China
| | - Xiu-Ping Liu
- Department of Pathophysiology, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Key Laboratory of Ministry of Education for Neurological Disorders, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China
| | - Xiu-Qing Yao
- Department of Pathophysiology, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Key Laboratory of Ministry of Education for Neurological Disorders, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Department of Neurology, The People's Hospital of Linfen City, Shangdong Province 276000, PR China
| | - Fu-Yuan Cao
- Department of Pathophysiology, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Key Laboratory of Ministry of Education for Neurological Disorders, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China
| | - Qun Wang
- Department of Pathophysiology, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Key Laboratory of Ministry of Education for Neurological Disorders, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China
| | - Jia-Yu Zhang
- Department of Pathophysiology, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Key Laboratory of Ministry of Education for Neurological Disorders, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, Yichang, China.
| | - Jian-Zhi Wang
- Department of Pathophysiology, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Key Laboratory of Ministry of Education for Neurological Disorders, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China.
| | - Gong-Ping Liu
- Department of Pathophysiology, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China; Key Laboratory of Ministry of Education for Neurological Disorders, the School of Basic Medicine, Tongji Medical College, Wuhan, PR China.
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38
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Grau C, Arató K, Fernández-Fernández JM, Valderrama A, Sindreu C, Fillat C, Ferrer I, de la Luna S, Altafaj X. DYRK1A-mediated phosphorylation of GluN2A at Ser(1048) regulates the surface expression and channel activity of GluN1/GluN2A receptors. Front Cell Neurosci 2014; 8:331. [PMID: 25368549 PMCID: PMC4201086 DOI: 10.3389/fncel.2014.00331] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 09/30/2014] [Indexed: 11/17/2022] Open
Abstract
N-methyl-D-aspartate glutamate receptors (NMDARs) play a pivotal role in neural development and synaptic plasticity, as well as in neurological disease. Since NMDARs exert their function at the cell surface, their density in the plasma membrane is finely tuned by a plethora of molecules that regulate their production, trafficking, docking and internalization in response to external stimuli. In addition to transcriptional regulation, the density of NMDARs is also influenced by post-translational mechanisms like phosphorylation, a modification that also affects their biophysical properties. We previously described the increased surface expression of GluN1/GluN2A receptors in transgenic mice overexpressing the Dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A), suggesting that DYRK1A regulates NMDARs. Here we have further investigated whether the density and activity of NMDARs were modulated by DYRK1A phosphorylation. Accordingly, we show that endogenous DYRK1A is recruited to GluN2A-containing NMDARs in the adult mouse brain, and we identify a DYRK1A phosphorylation site at Ser1048 of GluN2A, within its intracellular C-terminal domain. Mechanistically, the DYRK1A-dependent phosphorylation of GluN2A at Ser1048 hinders the internalization of GluN1/GluN2A, causing an increase of surface GluN1/GluN2A in heterologous systems, as well as in primary cortical neurons. Furthermore, GluN2A phosphorylation at Ser1048 increases the current density and potentiates the gating of GluN1/GluN2A receptors. We conclude that DYRK1A is a direct regulator of NMDA receptors and we propose a novel mechanism for the control of NMDAR activity in neurons.
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Affiliation(s)
- Cristina Grau
- Institute of Neuropathology, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat Barcelona, Spain
| | - Krisztina Arató
- Gene Regulation, Stem Cell and Cancer Programme, UPF and Center for Genomic Regulation (CRG) Barcelona, Spain ; CIBER de Enfermedades Raras (CIBERER) Barcelona, Spain
| | - José M Fernández-Fernández
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Pompeu Fabra University Barcelona, Spain
| | - Aitana Valderrama
- Institute of Neuropathology, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat Barcelona, Spain
| | - Carlos Sindreu
- Department of Anatomical Pathology, Pharmacology and Microbiology, University of Barcelona Barcelona, Spain
| | - Cristina Fillat
- CIBER de Enfermedades Raras (CIBERER) Barcelona, Spain ; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) Barcelona, Spain
| | - Isidre Ferrer
- Institute of Neuropathology, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat Barcelona, Spain
| | - Susana de la Luna
- Gene Regulation, Stem Cell and Cancer Programme, UPF and Center for Genomic Regulation (CRG) Barcelona, Spain ; CIBER de Enfermedades Raras (CIBERER) Barcelona, Spain ; Institució Catalana de Recerca i Estudis Avançats (ICREA) Barcelona, Spain
| | - Xavier Altafaj
- Institute of Neuropathology, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat Barcelona, Spain
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Xu F, Luk CC, Wiersma-Meems R, Baehre K, Herman C, Zaidi W, Wong N, Syed NI. Neuronal somata and extrasomal compartments play distinct roles during synapse formation between Lymnaea neurons. J Neurosci 2014; 34:11304-15. [PMID: 25143611 PMCID: PMC6615512 DOI: 10.1523/jneurosci.1651-14.2014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/07/2014] [Accepted: 07/15/2014] [Indexed: 12/21/2022] Open
Abstract
Proper synapse formation is pivotal for all nervous system functions. However, the precise mechanisms remain elusive. Moreover, compared with the neuromuscular junction, steps regulating the synaptogenic program at central cholinergic synapses remain poorly defined. In this study, we identified different roles of neuronal compartments (somal vs extrasomal) in chemical and electrical synaptogenesis. Specifically, the electrically synapsed Lymnaea pedal dorsal A cluster neurons were used to study electrical synapses, whereas chemical synaptic partners, visceral dorsal 4 (presynaptic, cholinergic), and left pedal dorsal 1 (LPeD1; postsynaptic) were explored for chemical synapse formation. Neurons were cultured in a soma-soma or soma-axon configuration and synapses explored electrophysiologically. We provide the first direct evidence that electrical synapses develop in a soma-soma, but not soma-axon (removal of soma) configuration, indicating the requirement of gene transcription regulation in the somata of both synaptic partners. In addition, the soma-soma electrical coupling was contingent upon trophic factors present in Lymnaea brain-conditioned medium. Further, we demonstrate that chemical (cholinergic) synapses between soma-soma and soma-axon pairs were indistinguishable, with both exhibiting a high degree of contact site and target cell type specificity. We also provide direct evidence that presynaptic cell contact-mediated, clustering of postsynaptic cholinergic receptors at the synaptic site requires transmitter-receptor interaction, receptor internalization, and a protein kinase C-dependent lateral migration toward the contact site. This study provides novel insights into synaptogenesis between central neurons revealing both distinct and synergistic roles of cell-cell signaling and extrinsic trophic factors in executing the synaptogenic program.
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Affiliation(s)
- Fenglian Xu
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Alberta T2N 4Z6, Canada
| | - Collin C Luk
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Alberta T2N 4Z6, Canada
| | - Ryanne Wiersma-Meems
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Alberta T2N 4Z6, Canada
| | - Kelly Baehre
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Alberta T2N 4Z6, Canada
| | - Cameron Herman
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Alberta T2N 4Z6, Canada
| | - Wali Zaidi
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Alberta T2N 4Z6, Canada
| | - Noelle Wong
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Alberta T2N 4Z6, Canada
| | - Naweed I Syed
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Alberta T2N 4Z6, Canada
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Ishrat T, Pillai B, Soliman S, Fouda AY, Kozak A, Johnson MH, Ergul A, Fagan SC. Low-dose candesartan enhances molecular mediators of neuroplasticity and subsequent functional recovery after ischemic stroke in rats. Mol Neurobiol 2014; 51:1542-53. [PMID: 25084762 DOI: 10.1007/s12035-014-8830-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 07/22/2014] [Indexed: 01/19/2023]
Abstract
We have previously reported that angiotensin type 1 receptor (AT1R) blockade with candesartan exerts neurovascular protection after experimental cerebral ischemia. Here, we tested the hypothesis that a low, subhypotensive dose of candesartan enhances neuroplasticity and subsequent functional recovery through enhanced neurotrophic factor expression in rats subjected to ischemia reperfusion injury. Male Wistar rats (290-300 g) underwent 90 min of middle cerebral artery occlusion (MCAO) and received candesartan (0.3 mg/kg) or saline at reperfusion and then once every 24 h for 7 days. Functional deficits were assessed in a blinded manner at 1, 3, 7, and 14 days after MCAO. Animals were sacrificed 14-day post-stroke and the brains perfused for infarct size by cresyl violet. Western blot and immunohistochemistry were used to assess the expression of growth factors and synaptic proteins. Candesartan-treated animals showed a significant reduction in the infarct size [t (13) = -5.5, P = 0.0001] accompanied by functional recovery in Bederson [F (1, 13) = 7.9, P = 0.015], beam walk [F (1, 13) = 6.7, P = 0.023], grip strength [F (1, 13) = 15.2, P = 0.0031], and rotarod performance [F (1, 14) = 29.8, P < 0.0001]. In addition, candesartan-treated animals showed significantly higher expression of active metalloproteinase-3 (MMP-3), laminin, and angiopoietin-1 (Ang-1). The expression of vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF) and its receptor was significantly increased in the animals treated with candesartan. Also, we observed significant increases in neuroplasticity markers, synaptophysin, and PSD-95. These results indicate that low-dose candesartan had a large and enduring effect on measures of plasticity, and this accompanied the functional recovery after ischemic stroke.
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van der Zee EA. Synapses, spines and kinases in mammalian learning and memory, and the impact of aging. Neurosci Biobehav Rev 2014; 50:77-85. [PMID: 24998408 DOI: 10.1016/j.neubiorev.2014.06.012] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 06/21/2014] [Accepted: 06/24/2014] [Indexed: 02/04/2023]
Abstract
Synapses are the building blocks of neuronal networks. Spines, the postsynaptic elements, are morphologically the most plastic part of the synapse. It is thought that spine plasticity underlies learning and memory processes, driven by kinases and cytoskeleton protein reorganization. Spine strength depends primarily on the number of incorporated glutamatergic receptors, which are more numerous in larger spines. Intrinsic and circadian fluctuations, occurring independently of presynaptic stimulation, demonstrate the native instability of spines. Despite innate spine instability some spines remain intact lifelong. Threats to spine survival are reduced by physical and mental activity, and declining sensory input, conditions characteristic for aging. Large spines are considered less vulnerable than thin spines, and in the older brain large spines are more abundant, whereas the thin spines are functionally weaker. It can be speculated that this shift towards memory spines contributes to enhanced retention of remote memories typically seen in the elderly. Gaining further insight in spine plasticity regulation, its homeostatic nature and how to maintain spine health will be important future research topics in Neuroscience.
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Affiliation(s)
- Eddy A van der Zee
- Department of Molecular Neurobiology, Centre for Behaviour and Neurosciences, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
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Regulation of N-methyl-D-aspartate receptors by disrupted-in-schizophrenia-1. Biol Psychiatry 2014; 75:414-424. [PMID: 23906531 PMCID: PMC3864617 DOI: 10.1016/j.biopsych.2013.06.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 06/12/2013] [Accepted: 06/19/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND Genetic studies have implicated disrupted-in-schizophrenia-1 (DISC1) as a risk factor for a wide range of mental conditions, including schizophrenia. Because N-methyl-D-aspartate receptor (NMDAR) dysfunction has been strongly linked to the pathophysiology of these conditions, we examined whether the NMDAR is a potential target of DISC1. METHODS DISC1 was knocked down with a small inference RNA. NMDAR-mediated currents were recorded and NMDAR expression was measured. RESULTS We found that cellular knockdown of DISC1 significantly increased NMDAR currents in cortical cultures, which were accompanied by an increase in the expression of NMDAR subunit, GluN2A. NMDAR-mediated synaptic response in prefrontal cortical pyramidal neurons was also increased by DISC1 knockdown in vivo. The effect of DISC1 knockdown on NMDAR currents in cortical cultures was blocked by protein kinase A (PKA) inhibitor, occluded by PKA activator, and prevented by phosphodiesterase 4 inhibitor. Knockdown of DISC1 caused a significant increase of cyclic adenosine monophosphate response element-binding protein (CREB) activity. Inhibiting CREB prevented the DISC1 deficiency-induced increase of NMDAR currents and GluN2A clusters. CONCLUSIONS Our results suggest that DISC1 exerts an important impact on NMDAR expression and function through a phosphodiesterase 4/PKA/CREB-dependent mechanism, which provides a potential molecular basis for the role of DISC1 in influencing NMDAR-dependent cognitive and emotional processes.
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43
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Recent progress in understanding subtype specific regulation of NMDA receptors by G Protein Coupled Receptors (GPCRs). Int J Mol Sci 2014; 15:3003-24. [PMID: 24562329 PMCID: PMC3958896 DOI: 10.3390/ijms15023003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 12/30/2013] [Accepted: 02/12/2014] [Indexed: 12/24/2022] Open
Abstract
G Protein Coupled Receptors (GPCRs) are the largest family of receptors whose ligands constitute nearly a third of prescription drugs in the market. They are widely involved in diverse physiological functions including learning and memory. NMDA receptors (NMDARs), which belong to the ionotropic glutamate receptor family, are likewise ubiquitously expressed in the central nervous system (CNS) and play a pivotal role in learning and memory. Despite its critical contribution to physiological and pathophysiological processes, few pharmacological interventions aimed directly at regulating NMDAR function have been developed to date. However, it is well established that NMDAR function is precisely regulated by cellular signalling cascades recruited downstream of G protein coupled receptor (GPCR) stimulation. Accordingly, the downstream regulation of NMDARs likely represents an important determinant of outcome following treatment with neuropsychiatric agents that target selected GPCRs. Importantly, the functional consequence of such regulation on NMDAR function varies, based not only on the identity of the GPCR, but also on the cell type in which relevant receptors are expressed. Indeed, the mechanisms responsible for regulating NMDARs by GPCRs involve numerous intracellular signalling molecules and regulatory proteins that vary from one cell type to another. In the present article, we highlight recent findings from studies that have uncovered novel mechanisms by which selected GPCRs regulate NMDAR function and consequently NMDAR-dependent plasticity.
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Uzunova G, Hollander E, Shepherd J. The role of ionotropic glutamate receptors in childhood neurodevelopmental disorders: autism spectrum disorders and fragile x syndrome. Curr Neuropharmacol 2014; 12:71-98. [PMID: 24533017 PMCID: PMC3915351 DOI: 10.2174/1570159x113116660046] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 08/20/2013] [Accepted: 09/25/2013] [Indexed: 12/20/2022] Open
Abstract
Autism spectrum disorder (ASD) and Fragile X syndrome (FXS) are relatively common childhood neurodevelopmental disorders with increasing incidence in recent years. They are currently accepted as disorders of the synapse with alterations in different forms of synaptic communication and neuronal network connectivity. The major excitatory neurotransmitter system in brain, the glutamatergic system, is implicated in learning and memory, synaptic plasticity, neuronal development. While much attention is attributed to the role of metabotropic glutamate receptors in ASD and FXS, studies indicate that the ionotropic glutamate receptors (iGluRs) and their regulatory proteins are also altered in several brain regions. Role of iGluRs in the neurobiology of ASD and FXS is supported by a weight of evidence that ranges from human genetics to in vitro cultured neurons. In this review we will discuss clinical, molecular, cellular and functional changes in NMDA, AMPA and kainate receptors and the synaptic proteins that regulate them in the context of ASD and FXS. We will also discuss the significance for the development of translational biomarkers and treatments for the core symptoms of ASD and FXS.
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Affiliation(s)
- Genoveva Uzunova
- Autism and Obsessive Compulsive Spectrum Program, Department of Psychiatry, Montefiore Medical Center, Albert Einstein College of Medicine, 111 East 210th St, Bronx, New York 10467-2490
| | - Eric Hollander
- Autism and Obsessive Compulsive Spectrum Program, Department of Psychiatry, Montefiore Medical Center, Albert Einstein College of Medicine, 111 East 210th St, Bronx, New York 10467-2490
| | - Jason Shepherd
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, 531A Wintrobe, 20N 1900 E, Salt Lake City, Utah 84132
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45
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Dyrvig M, Christiansen SH, Woldbye DPD, Lichota J. Temporal gene expression profile after acute electroconvulsive stimulation in the rat. Gene 2014; 539:8-14. [PMID: 24518690 DOI: 10.1016/j.gene.2014.01.072] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 01/17/2014] [Accepted: 01/25/2014] [Indexed: 01/20/2023]
Abstract
Electroconvulsive therapy (ECT) remains one of the most effective treatments of major depression. It has been suggested that the mechanisms of action involve gene expression. In recent decades there have been several investigations of gene expression following both acute and chronic electroconvulsive stimulation (ECS). These studies have focused on several distinct gene targets but have generally included only few time points after ECS for measuring gene expression. Here we measured gene expression of three types of genes: Immediate early genes, synaptic proteins, and neuropeptides at six time points following an acute ECS. We find significant increases for c-Fos, Egr1, Neuritin 1 (Nrn 1), Bdnf, Snap29, Synaptotagmin III (Syt 3), Synapsin I (Syn 1), and Psd95 at differing time points after ECS. For some genes these changes are prolonged whereas for others they are transient. Npy expression significantly increases whereas the gene expression of its receptors Npy1r, Npy2r, and Npy5r initially decreases. These decreases are followed by a significant increase for Npy2r, suggesting anticonvulsive adaptations following seizures. In summary, we find distinct changes in mRNA quantities that are characteristic for each gene. Considering the observed transitory and inverse changes in expression patterns, these data underline the importance of conducting measurements at several time points post-ECS.
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Affiliation(s)
- Mads Dyrvig
- Laboratory of Neurobiology, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Søren H Christiansen
- Laboratory of Neural Plasticity, Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - David P D Woldbye
- Laboratory of Neural Plasticity, Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Jacek Lichota
- Laboratory of Neurobiology, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
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46
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Rivera HM, Bethea CL. Ovarian steroids increase PSD-95 expression and dendritic spines in the dorsal raphe of ovariectomized macaques. Synapse 2013; 67:897-908. [PMID: 23959764 DOI: 10.1002/syn.21702] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 07/30/2013] [Accepted: 08/10/2013] [Indexed: 01/19/2023]
Abstract
Estradiol (E) and progesterone (P) promote spinogenesis in several brain areas. Intracellular signaling cascades that promote spinogenesis involve RhoGTPases, glutamate signaling and synapse assembly. We found that in serotonin neurons, E ± P administration increases (a) gene and protein expression of RhoGTPases, (b) gene expression of glutamate receptors, and (c) gene expression of pivotal synapse assembly proteins. Therefore, in this study we determined whether structural changes in dendritic spines in the dorsal raphe follow the observed changes in gene and protein expression. Dendritic spines were examined with immunogold silver staining of a spine marker protein, postsynaptic density-95 (PSD-95) and with Golgi staining. In the PSD-95 study, adult Ovx monkeys received placebo, E, P, or E + P for 1 month (n = 3/group). Sections were immunostained for PSD-95 and the number of PSD-95-positive puncta was determined with stereology. E, P, and E + P treatment significantly increased the total number of PSD-95-positive puncta (ANOVA, P = 0.04). In the golgi study, adult Ovx monkeys received placebo, E or E + P for 1 month (n = 3-4) and the midbrain was golgi-stained. A total of 80 neurons were analyzed with Neurolucida software. There was a significant difference in spine density that depended on branch order (two-way ANOVA). E + P treatment significantly increased spine density in higher-order (3°-5°) dendritic branches relative to Ovx group (Bonferroni, P < 0.05). In summary, E + P leads to the elaboration of dendritic spines on dorsal raphe neurons. The ability of E to induce PSD-95, but not actual spines, suggests either a sampling or time lag issue. Increased spinogenesis on serotonin dendrites would facilitate excitatory glutamatergic input and, in turn, increase serotonin neurotransmission throughout the brain.
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Affiliation(s)
- Heidi M Rivera
- Division of Reproductive Sciences, Oregon National Primate Research Center, Beaverton, Oregon, 97006
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47
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Predicting protein-protein interactions in the post synaptic density. Mol Cell Neurosci 2013; 56:128-39. [PMID: 23628905 DOI: 10.1016/j.mcn.2013.04.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 04/09/2013] [Accepted: 04/19/2013] [Indexed: 12/27/2022] Open
Abstract
The post synaptic density (PSD) is a specialization of the cytoskeleton at the synaptic junction, composed of hundreds of different proteins. Characterizing the protein components of the PSD and their interactions can help elucidate the mechanism of long-term changes in synaptic plasticity, which underlie learning and memory. Unfortunately, our knowledge of the proteome and interactome of the PSD is still partial and noisy. In this study we describe a computational framework to improve the reconstruction of the PSD network. The approach is based on learning the characteristics of PSD protein interactions from a set of trusted interactions, expanding this set with data collected from large scale repositories, and then predicting novel interaction with proteins that are suspected to reside in the PSD. Using this method we obtained thirty predicted interactions, with more than half of which having supporting evidence in the literature. We discuss in details two of these new interactions, Lrrtm1 with PSD-95 and Src with Capg. The first may take part in a mechanism underlying glutamatergic dysfunction in schizophrenia. The second suggests an alternative mechanism to regulate dendritic spines maturation.
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48
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Naylor DE, Liu H, Niquet J, Wasterlain CG. Rapid surface accumulation of NMDA receptors increases glutamatergic excitation during status epilepticus. Neurobiol Dis 2013; 54:225-38. [PMID: 23313318 DOI: 10.1016/j.nbd.2012.12.015] [Citation(s) in RCA: 141] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 12/20/2012] [Accepted: 12/28/2012] [Indexed: 02/06/2023] Open
Abstract
After 1h of lithium-pilocarpine status epilepticus (SE), immunocytochemical labeling of NMDA receptor NR1 subunits reveals relocation of subunits from the interior to the cell surface of dentate gyrus granule cells and CA3 pyramidal cells. Simultaneously, an increase in NMDA-miniature excitatory postsynaptic currents (mEPSC) as well as an increase in NMDA receptor-mediated tonic currents is observed in hippocampal slices after SE. Mean-variance analysis of NMDA-mEPSCs estimates that the number of functional postsynaptic NMDA receptors per synapse increases 38% during SE, and antagonism by ifenprodil suggests that an increase in the surface representation of NR2B-containing NMDA receptors is responsible for the augmentation of both the phasic and tonic excitatory currents with SE. These results provide a potential mechanism for an enhancement of glutamatergic excitation that maintains SE and may contribute to excitotoxic injury during SE. Therapies that directly antagonize NMDA receptors may be a useful therapeutic strategy during refractory SE.
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Affiliation(s)
- David E Naylor
- Department of Neurology, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, USA; Department of Neurology, Veterans Administration Greater Los Angeles Healthcare System, USA.
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Borlikova GG, Trejo M, Mably AJ, Mc Donald JM, Sala Frigerio C, Regan CM, Murphy KJ, Masliah E, Walsh DM. Alzheimer brain-derived amyloid β-protein impairs synaptic remodeling and memory consolidation. Neurobiol Aging 2012. [PMID: 23182244 DOI: 10.1016/j.neurobiolaging.2012.10.028] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Aggregation of the amyloid β-protein (Aβ) is believed to play a central role in initiating the molecular cascade that culminates in Alzheimer-type dementia (AD), a disease which in its early stage is characterized by synaptic loss and impairment of episodic memory. Here we show that intracerebroventricular injection of Aβ-containing water-soluble extracts of AD brain inhibits consolidation of the memory of avoidance learning in the rat and that this effect is highly dependent on the interval between learning and administration. When injected at 1 hour post training extracts from 2 different AD brains significantly impaired recall tested at 48 hours. Ultrastructural examination of hippocampi from animals perfused after 48 hours revealed that Aβ-mediated impairment of avoidance memory was associated with lower density of synapses and altered synaptic structure in the dentate gyrus and CA1 fields. These behavioral and ultrastructural data suggest that human brain-derived Aβ impairs formation of long-term memory by compromising the structural plasticity essential for consolidation and that Aβ targets processes initiated very early in the consolidation pathway.
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Affiliation(s)
- Gilyana G Borlikova
- Laboratory for Neurodegenerative Research, School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Dublin, Republic of Ireland
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50
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Borschel WF, Myers JM, Kasperek EM, Smith TP, Graziane NM, Nowak LM, Popescu GK. Gating reaction mechanism of neuronal NMDA receptors. J Neurophysiol 2012; 108:3105-15. [PMID: 22993263 DOI: 10.1152/jn.00551.2012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The activation mechanisms of recombinant N-methyl-d-aspartate receptors (NRs) have been established in sufficient detail to account for their single channel and macroscopic responses; however, the reaction mechanism of native NRs remains uncertain due to indetermination of the isoforms expressed and possible neuron-specific factors. To delineate the activation mechanism of native NRs, we examined the kinetic properties of currents generated by individual channels located at the soma of cultured rat neurons. Cells were dissociated from the embryonic cerebral cortex or hippocampus, and on-cell single channel recordings were done between 4 and 50 days in vitro (DIV). We observed two types of kinetics that correlated with the age of the culture. When we segregated recordings by culture age, we found that receptors recorded from early (4-33 DIV) and late (25-50 DIV) cultures had smaller unitary conductances but had kinetic profiles that matched closely those of recombinant 2B- or 2A-containing receptors, respectively. In addition, we examined the effects of cotransfection with postsynaptic density protein 95 or neuropilin tolloid-like protein 1 on recombinant receptors expressed in human embryonic kidney-293 cells. Our results add support to the view that neuronal cultures recapitulate the developmental patterns of receptor expression observed in the intact animal and demonstrate that the activation mechanism of somatic neuronal NRs is similar to that described for recombinant receptors of defined subunit composition.
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Affiliation(s)
- William F Borschel
- Department of Biochemistry, School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
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