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Iacobucci GJ, Popescu GK. Calcium- and calmodulin-dependent inhibition of NMDA receptor currents. Biophys J 2024; 123:277-293. [PMID: 38140727 PMCID: PMC10870176 DOI: 10.1016/j.bpj.2023.12.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 12/05/2023] [Accepted: 12/19/2023] [Indexed: 12/24/2023] Open
Abstract
Calcium ions (Ca2+) reduce NMDA receptor currents through several distinct mechanisms. Among these, calmodulin (CaM)-dependent inhibition (CDI) accomplishes rapid, reversible, and incomplete reduction of the NMDA receptor currents in response to elevations in intracellular Ca2+. Quantitative and mechanistic descriptions of CDI of NMDA receptor-mediated signals have been marred by variability originating, in part, from differences in the conditions and metrics used to evaluate this process across laboratories. Recent ratiometric approaches to measure the magnitude and kinetics of NMDA receptor CDI have facilitated rapid insights into this phenomenon. Notably, the kinetics and magnitude of NMDA receptor CDI depend on the degree of saturation of its CaM binding sites, which represent the bona fide calcium sensor for this type of inhibition, the kinetics and magnitude of the Ca2+ signal, which depends on the biophysical properties of the NMDA receptor or of adjacent Ca2+ sources, and on the relative distribution of Ca2+ sources and CaM molecules. Given that all these factors vary widely during development, across cell types, and with physiological and pathological states, it is important to understand how NMDA receptor CDI develops and how it contributes to signaling in the central nervous system. Here, we review briefly these recent advances and highlight remaining questions about the structural and kinetic mechanisms of NMDA receptor CDI. Given that pathologies can arise from several sources, including mutations in the NMDA receptor and in CaM, understanding how CaM responds to intracellular Ca2+ signals to initiate conformational changes in NMDA receptors, and mapping the structural domains responsible will help to envision novel therapeutic strategies to neuropsychiatric diseases, which presently have limited available treatments.
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Affiliation(s)
- Gary J Iacobucci
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, SUNY, Buffalo, New York
| | - Gabriela K Popescu
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, SUNY, Buffalo, New York.
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Al-Musawi AF, Al-Hakeim HK, Al-Khfaji ZA, Al-Haboby IH, Almulla AF, Stoyanov DS, Maes M. In Schizophrenia, the Effects of the IL-6/IL-23/Th17 Axis on Health-Related Quality of Life and Disabilities Are Partly Mediated by Generalized Cognitive Decline and the Symptomatome. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph192215281. [PMID: 36429996 PMCID: PMC9690590 DOI: 10.3390/ijerph192215281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 10/31/2022] [Accepted: 11/15/2022] [Indexed: 05/08/2023]
Abstract
Schizophrenia patients show increased disabilities and lower quality of life (DisQoL). Nevertheless, there are no data on whether the activation of the interleukin (IL)-6, IL-23, T helper (Th)-17 axis, and lower magnesium and calcium levels impact DisQoL scores. This study recruited 90 patients with schizophrenia (including 40 with deficit schizophrenia) and 40 healthy controls and assessed the World Health Association QoL instrument-Abbreviated version and Sheehan Disability scale, Brief Assessment of Cognition in Schizophrenia (BACS), IL-6, IL-23, IL-17, IL-21, IL-22, tumor necrosis factor (TNF)-α, magnesium and calcium. Regression analyses showed that a large part of the first factor extracted from the physical, psychological, social and environmental HR-QoL and interference with school/work, social life, and home responsibilities was predicted by a generalized cognitive deterioration (G-CoDe) index (a latent vector extracted from BACs scores), and the first vector extracted from various symptom domains ("symptomatome"), whereas the biomarkers had no effects. Partial Least Squares analysis showed that the IL6IL23Th17 axis and magnesium/calcium had highly significant total (indirect + direct) effects on HR-QoL/disabilities, which were mediated by G-CoDe and the symptomatome (a first factor extracted from negative and positive symptoms). The IL6IL23Th17 axis explained 63.1% of the variance in the behavioral-cognitive-psycho-social (BCPS) worsening index a single latent trait extracted from G-CoDe, symptomatome, HR-QoL and disability data. In summary, the BCPS worsening index is partly caused by the neuroimmunotoxic effects of the IL6IL23Th17 axis in subjects with lowered antioxidant defenses (magnesium and calcium), thereby probably damaging the neuronal circuits that may underpin deficit schizophrenia.
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Affiliation(s)
- Ali Fattah Al-Musawi
- Department of Clinical Pharmacy and Laboratory Sciences, College of Pharmacy, University of Al-Kafeel, Kufa 54001, Iraq
| | | | - Zahraa Abdulrazaq Al-Khfaji
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Al-Zahraa University for Women, Karbala 56001, Iraq
| | | | - Abbas F. Almulla
- Medical Laboratory Technology Department, College of Medical Technology, The Islamic University, Najaf 54001, Iraq
- Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, PathumWan, Bangkok 10330, Thailand
| | - Drozdstoj St. Stoyanov
- Department of Psychiatry, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria
- Research Institute, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria
| | - Michael Maes
- Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, PathumWan, Bangkok 10330, Thailand
- Department of Psychiatry, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria
- Research Institute, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria
- IMPACT, School of Medicine, Barwon Health, The Institute for Mental and Physical Health and Clinical Translation, Deakin University, Geelong 3217, Australia
- Correspondence:
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Al-Hakeim HK, Al-Musawi AF, Al-Mulla A, Al-Dujaili AH, Debnath M, Maes M. The interleukin-6/interleukin-23/T helper 17-axis as a driver of neuro-immune toxicity in the major neurocognitive psychosis or deficit schizophrenia: A precision nomothetic psychiatry analysis. PLoS One 2022; 17:e0275839. [PMID: 36256663 PMCID: PMC9578624 DOI: 10.1371/journal.pone.0275839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 09/24/2022] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Schizophrenia and especially deficit schizophrenia (DSCZ) are characterized by increased activity of neuroimmunotoxic pathways and a generalized cognitive decline (G-CoDe). There is no data on whether the interleukin (IL)-6/IL-23/T helper 17 (IL-6/IL-23/Th17)-axis is more associated with DSCZ than with non-deficit schizophrenia (NDSCZ) and whether changes in this axis are associated with the G-CoDe and the phenome (a factor extracted from all symptom domains) of schizophrenia. METHODS This study included 45 DSCZ and 45 NDSCZ patients and 40 controls and delineated whether the IL-6/IL-23/Th17 axis, trace elements (copper, zinc) and ions (magnesium, calcium) are associated with DSCZ, the G-CoDe and the schizophrenia phenome. RESULTS Increased plasma IL-23 and IL-6 levels were associated with Th17 upregulation, assessed as a latent vector (LV) extracted from IL-17, IL-21, IL-22, and TNF-α. The IL-6/IL-23/Th17-axis score, as assessed by an LV extracted from IL-23, IL-6, and the Th17 LV, was significantly higher in DSCZ than in NDSCZ and controls. We discovered that 70.7% of the variance in the phenome was explained by the IL-6/IL-23/Th17-axis (positively) and the G-CoDe and IL-10 (both inversely); and that 54.6% of the variance in the G-CoDe was explained by the IL-6/IL-23/Th17 scores (inversely) and magnesium, copper, calcium, and zinc (all positively). CONCLUSION The pathogenic IL-6/IL-23/Th17-axis contributes to the generalized neurocognitive deficit and the phenome of schizophrenia, especially that of DSCZ, due to its key role in peripheral inflammation and neuroinflammation and its consequent immunotoxic effects on neuronal circuits. These clinical impairments are more prominent in subjects with lowered IL-10, magnesium, calcium, and zinc.
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Affiliation(s)
| | - Ali Fattah Al-Musawi
- Department of Clinical Pharmacy and Laboratory Sciences, College of Pharmacy, University of Al-Kafeel, Kufa, Iraq
| | - Abbas Al-Mulla
- Medical Laboratory Technology Department, College of Medical Technology, The Islamic University, Najaf, Iraq
| | | | - Monojit Debnath
- Department of Human Genetics, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Michael Maes
- Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Department of Psychiatry, Medical University of Plovdiv, Plovdiv, Bulgaria
- IMPACT Strategic Research Centre, Deakin University, Geelong, VIC, Australia
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Lee J, Kim HJ. Normal Aging Induces Changes in the Brain and Neurodegeneration Progress: Review of the Structural, Biochemical, Metabolic, Cellular, and Molecular Changes. Front Aging Neurosci 2022; 14:931536. [PMID: 35847660 PMCID: PMC9281621 DOI: 10.3389/fnagi.2022.931536] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/13/2022] [Indexed: 11/30/2022] Open
Abstract
Aging is accompanied by many changes in brain and contributes to progressive cognitive decline. In contrast to pathological changes in brain, normal aging brain changes have relatively mild but important changes in structural, biochemical and molecular level. Representatively, aging associated brain changes include atrophy of tissues, alteration in neurotransmitters and damage accumulation in cellular environment. These effects have causative link with age associated changes which ultimately results in cognitive decline. Although several evidences were found in normal aging changes of brain, it is not clearly integrated. Figuring out aging related changes in brain is important as aging is the process that everyone goes through, and comprehensive understanding may help to progress further studies. This review clarifies normal aging brain changes in an asymptotic and comprehensive manner, from a gross level to a microscopic and molecular level, and discusses potential approaches to seek the changes with cognitive decline.
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Affiliation(s)
- Jiseon Lee
- Department of Neurology, Hanyang University Hospital, Seoul, South Korea
| | - Hee-Jin Kim
- Department of Neurology, Hanyang University Hospital, Seoul, South Korea
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Gao Y, Mack AA, Litteral C, Delamere NA, El-Mallakh RS. NMDA receptor inhibition prevents intracellular sodium elevations in human olfactory neuroepithelial precursors derived from bipolar patients. Sci Rep 2022; 12:10437. [PMID: 35729322 PMCID: PMC9213398 DOI: 10.1038/s41598-022-14187-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 06/02/2022] [Indexed: 11/24/2022] Open
Abstract
Dysregulation of ion flux across membranes and glutamate-induced excitotoxicity appear to be important pathophysiologic abnormalities in bipolar illness. Understanding ion control and responses to ionic stress is important to decipher the pathogenesis of this disorder. Monensin alone significantly increased [Na]i in ONPs from bipolar individuals (5.08 ± 0.71 vs baseline 3.13 ± 0.93, P = 0.03) and AP5 had no effect (2.0 ± 1.2 vs baseline 3.13 ± 0.93, P = 0.27). However, the combination of AP5 and monensin resulted in normalization of [Na]i (3.25 ± 1.28 vs baseline 3.13 ± 0.93, P = 0.89). This effect was not observed in cells from non-bipolar individuals (monensin alone, 1.72 ± 1.10 vs baseline 2.42 ± 1.80, P = 0.25; AP5 alone, 1.37 ± 0.74 vs baseline 2.42 ± 1.80; AP5 combined with monensin, 1.53 ± 0.98 vs baseline 2.42 ± 1.80, P = 0.31). Sodium regulation is central to neuronal function and may be disturbed in patients with bipolar disorder. Monensin is an ionophore, meaning that it incorporates itself into the membrane and allows sodium to enter independent of cellular membrane proteins. While the mechanism remains obscure, the observation that the NMDA receptor antagonist, AP5, normalizes [Na]i only in olfactory neuroepithelial precursors obtained from bipolar illness may provide novel insights into ion regulation in tissues from subjects with bipolar illness.
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Affiliation(s)
- Yonglin Gao
- Department of Psychiatry and Behavioral Sciences, Mood Disorders Research Program, Depression Center, University of Louisville School of Medicine, Louisville, KY, USA
| | - Aaron A Mack
- Department of Psychiatry and Behavioral Sciences, Mood Disorders Research Program, Depression Center, University of Louisville School of Medicine, Louisville, KY, USA
| | - Carleigh Litteral
- Department of Psychiatry and Behavioral Sciences, Mood Disorders Research Program, Depression Center, University of Louisville School of Medicine, Louisville, KY, USA
| | - Nicholas A Delamere
- Department of Physiology, University of Arizona, PO Box 245051, Tucson, AZ, 85724-5051, USA
| | - Rif S El-Mallakh
- Department of Psychiatry and Behavioral Sciences, Mood Disorders Research Program, Depression Center, University of Louisville School of Medicine, Louisville, KY, USA.
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Sancho-Alonso M, Taoro-Gonzalez L, Cabrera-Pastor A, Felipo V, Teruel-Martí V. Hyperammonemia Alters the Function of AMPA and NMDA Receptors in Hippocampus: Extracellular cGMP Reverses Some of These Alterations. Neurochem Res 2022; 47:2016-2031. [PMID: 35386048 DOI: 10.1007/s11064-022-03588-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 03/17/2022] [Accepted: 03/20/2022] [Indexed: 11/25/2022]
Abstract
Chronic hyperammonemia alters membrane expression of AMPA and NMDA receptors subunits in hippocampus leading to impaired memory and learning. Increasing extracellular cGMP normalizes these alterations. However, it has not been studied whether hyperammonemia alters the function of AMPA and NMDA receptors. The aims of this work were: (1) assess if hyperammonemia alters AMPA and NMDA receptors function; (2) analyze if extracellular cGMP reverses these alterations. A multielectrode array device was used to stimulate Schäffer collaterals and record postsynaptic currents in the CA1 region in hippocampal slices from control and hyperammonemic rats and analyze different features of the excitatory postsynaptic potentials. Hyperammonemia reduces the amplitude and delays appearance of AMPA EPSPs, whereas increases amplitude, hyperpolarization, depolarization and desensitization area of the NMDA EPSPs. These alterations in AMPA and NMDA function are accentuated as the stimulation intensity increases. Adding extracellular cGMP reverses the alteration in amplitude in both, AMPA and NMDA EPSPs. In control slices extracellular cGMP decreases the AMPA and NMDA EPSPs amplitude and delays the response of neurons and the return to the resting potential at all stimulation intensities. In conclusion, hyperammonemia decreases the AMPA response, whereas increases the NMDA response and extracellular cGMP reverses these alterations.
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Affiliation(s)
- María Sancho-Alonso
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, 46012, Valencia, Spain
| | - Lucas Taoro-Gonzalez
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, 46012, Valencia, Spain
| | - Andrea Cabrera-Pastor
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, 46012, Valencia, Spain.,Fundación Investigación Hospital Clínico, Instituto de Investigación Sanitaria (INCLIVA), 46010, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, 46012, Valencia, Spain.
| | - Vicent Teruel-Martí
- Anatomy and Human Embryology Department, Faculty of Medicine, University of Valencia, 46010, Valencia, Spain
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Ruden JB, Dixit M, Zepeda JC, Grueter BA, Dugan LL. Robust Expression of Functional NMDA Receptors in Human Induced Pluripotent Stem Cell-Derived Neuronal Cultures Using an Accelerated Protocol. Front Mol Neurosci 2021; 14:777049. [PMID: 34899184 PMCID: PMC8661903 DOI: 10.3389/fnmol.2021.777049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 11/05/2021] [Indexed: 11/13/2022] Open
Abstract
N-methyl-D-aspartate (NMDA) receptors are critical for higher-order nervous system function, but in previously published protocols to convert human induced pluripotent stem cells (iPSCs) to mature neurons, functional NMDA receptors (NMDARs) are often either not reported or take an extended time to develop. Here, we describe a protocol to convert human iPSC-derived neural progenitor cells (NPCs) to mature neurons in only 37 days. We demonstrate that the mature neurons express functional NMDARs exhibiting ligand-activated calcium flux, and we document the presence of NMDAR-mediated electrically evoked postsynaptic current. In addition to being more rapid than previous procedures, our protocol is straightforward, does not produce organoids which are difficult to image, and does not involve co-culture with rodent astrocytes. This could enhance our ability to study primate/human-specific aspects of NMDAR function and signaling in health and disease.
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Affiliation(s)
- Jacob B Ruden
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, United States
| | - Mrinalini Dixit
- Division of Geriatric Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - José C Zepeda
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
| | - Brad A Grueter
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, United States.,Department of Pharmacology, Vanderbilt University, Nashville, TN, United States.,Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN, United States.,Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, United States.,Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, United States.,Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, United States
| | - Laura L Dugan
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, United States.,Division of Geriatric Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States.,VA Tennessee Valley Geriatric Research, Education, and Clinical Center (GRECC), Nashville, TN, United States
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Zhao J, Wang Y, Gao J, Jing Y, Xin W. Berberine Mediated Positive Inotropic Effects on Rat Hearts via a Ca 2+-Dependent Mechanism. Front Pharmacol 2020; 11:821. [PMID: 32581792 PMCID: PMC7289965 DOI: 10.3389/fphar.2020.00821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 05/19/2020] [Indexed: 11/13/2022] Open
Abstract
Previous studies showed that berberine, an alkaloid from Coptis Chinensis Franch, might exert a positive inotropic effect on the heart. However, the underlying mechanisms were unclear. Here, we reported that berberine at 10–20 µM increased the left ventricular (LV) developed pressure and the maximal rate of the pressure rising, and it increased the maximal rate of the pressure descending at 20 µM in Langendorff-perfused isolated rat hearts. These effects diminished with the concentration of berberine increasing to 50 µM. In the concentration range of 50–300 µM, berberine increased the isometric tension of isolated left ventricular muscle (LVM) strips with or without electrical stimulations, and it (30–300 µM) also increased the intracellular Ca2+ level in the isolated LV myocytes. The removal of extracellular Ca2+ hindered the berberine-induced increases in the tension of LVM strips and the intracellular Ca2+ level of LV myocytes. These suggested that berberine might exert its positive inotropic effects via enhancing Ca2+ influx. The blockade of L-type Ca2+ channels (LTCCs) with nifedipine significantly attenuated 300 μM berberine-induced tension increase in LVM strips but not the increase in the intracellular Ca2+ level. Berberine (300 μM) further increased the LVM tension following the treatment with the LTCC opener FPL-64716 (10 μM), indicating an LTCC-independent effect of berberine. Lowering extracellular Na+ attenuated the berberine-induced increases in both the tension of LVM strips and the intracellular Ca2+ level of LV myocytes. In conclusion, berberine might exert a positive inotropic effect on the isolated rat heart by enhancing the Ca2+ influx in LV myocytes; these were extracellular Na+-dependent.
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Affiliation(s)
- Junli Zhao
- College of Pharmaceutical Sciences, Southwest University, Chongqing, China
| | - Yaqian Wang
- College of Pharmaceutical Sciences, Southwest University, Chongqing, China
| | - Jie Gao
- College of Pharmaceutical Sciences, Southwest University, Chongqing, China
| | - Yang Jing
- College of Pharmaceutical Sciences, Southwest University, Chongqing, China
| | - Wenkuan Xin
- College of Pharmaceutical Sciences, Southwest University, Chongqing, China
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Rajani V, Sengar AS, Salter MW. Tripartite signalling by NMDA receptors. Mol Brain 2020; 13:23. [PMID: 32070387 PMCID: PMC7029596 DOI: 10.1186/s13041-020-0563-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 02/03/2020] [Indexed: 12/31/2022] Open
Abstract
N-methyl-d-aspartate receptors (NMDARs) are excitatory glutamatergic receptors that are fundamental for many neuronal processes, including synaptic plasticity. NMDARs are comprised of four subunits derived from heterogeneous subunit families, yielding a complex diversity in NMDAR form and function. The quadruply-liganded state of binding of two glutamate and two glycine molecules to the receptor drives channel gating, allowing for monovalent cation flux, Ca2+ entry and the initiation of Ca2+-dependent signalling. In addition to this ionotropic function, non-ionotropic signalling can be initiated through the exclusive binding of glycine or of glutamate to the NMDAR. This binding may trigger a transmembrane conformational change of the receptor, inducing intracellular protein-protein signalling between the cytoplasmic domain and secondary messengers. In this review, we outline signalling cascades that can be activated by NMDARs and propose that the receptor transduces signalling through three parallel streams: (i) signalling via both glycine and glutamate binding, (ii) signalling via glycine binding, and (iii) signalling via glutamate binding. This variety in signal transduction mechanisms and downstream signalling cascades complements the widespread prevalence and rich diversity of NMDAR activity throughout the central nervous system and in disease pathology.
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Affiliation(s)
- Vishaal Rajani
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada
| | - Ameet S Sengar
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada
| | - Michael W Salter
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada. .,Department of Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada.
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Iacobucci GJ, Popescu GK. Spatial Coupling Tunes NMDA Receptor Responses via Ca 2+ Diffusion. J Neurosci 2019; 39:8831-8844. [PMID: 31519826 PMCID: PMC6832682 DOI: 10.1523/jneurosci.0901-19.2019] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 08/11/2019] [Accepted: 09/03/2019] [Indexed: 12/11/2022] Open
Abstract
In the CNS, NMDA receptors generate large and highly regulated Ca2+ signals, which are critical for synaptic development and plasticity. They are highly clustered at postsynaptic sites and along dendritic arbors, but whether this spatial arrangement affects their output is unknown. Synaptic NMDA receptor currents are subject to Ca2+-dependent inactivation (CDI), a type of activity-dependent inhibition that requires intracellular Ca2+ and calmodulin (CaM). We asked whether Ca2+ influx through a single NMDA receptor influences the activity of nearby NMDA receptors, as a possible coupling mechanism. Using cell-attached unitary current recordings from GluN1-2a/GluN2A receptors expressed in human HEK293 cells and from NMDA receptors native to hippocampal neurons from male and female rats, we recorded unitary currents from multichannel patches and used a coupled Markov model to determine the extent of signal coupling (κ). In the absence of extracellular Ca2+, we observed no cooperativity (κ < 0.1), whereas in 1.8 mm external Ca2+, both recombinant and native channels showed substantial negative cooperativity (κ = 0.27). Intracellular Ca2+ chelation or overexpression of a Ca2+-insensitive CaM mutant, reduced coupling, which is consistent with CDI representing the coupling mechanism. In contrast, cooperativity increased substantially (κ = 0.68) when overexpressing the postsynaptic scaffolding protein PSD-95, which increased receptor clustering. Together, these new results demonstrate that NMDA receptor currents are negatively coupled through CDI, and the degree of coupling can be tuned by the distance between receptors. Therefore, channel clustering can influence the activity-dependent reduction in NMDA receptor currents.SIGNIFICANCE STATEMENT At central synapses, NMDA receptors are a major class of excitatory glutamate-gated channels and a source of activity-dependent Ca2+ influx. In turn, fluxed Ca2+ ions bind to calmodulin-primed receptors and reduce further entry, through an autoinhibitory mechanism known as Ca2+ -dependent inactivation (CDI). Here, we show that the diffusion of fluxed Ca2+ between active channels situated within submicroscopic distances amplified receptor inactivation. Thus, calmodulin-mediated gating modulation, an evolutionarily conserved regulatory mechanism, endows synapses with sensitivity to both the temporal sequence and spatial distribution of Ca2+ signals. Perturbations in this mechanism, which coordinates the activity of NMDA receptors within a cluster, may cause signaling alterations that contribute to neuropsychiatric conditions.
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Affiliation(s)
- Gary J Iacobucci
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, New York 14206
| | - Gabriela K Popescu
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, New York 14206
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Kumar G, Kasiviswanathan U, Mukherjee S, Kumar Mahto S, Sharma N, Patnaik R. Changes in electrolyte concentrations alter the impedance during ischemia-reperfusion injury in rat brain. Physiol Meas 2019; 40:105004. [DOI: 10.1088/1361-6579/ab47ee] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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12
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Afolabi BA, Adedara IA, Souza DO, Rocha JBT. Dietary co-exposure to methylmercury and monosodium glutamate disrupts cellular and behavioral responses in the lobster cockroach, Nauphoeta cinerea model. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2018; 64:70-77. [PMID: 30300794 DOI: 10.1016/j.etap.2018.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 09/03/2018] [Accepted: 09/12/2018] [Indexed: 06/08/2023]
Abstract
The present study aims to investigate the effect of monosodium glutamate (MSG) both separately and combined with a low dose of methylmercury (MeHg) on behavioral and biochemical parameters in Nauphoeta cinerea (lobster cockroach). Cockroaches were fed with the basal diet alone, basal diet + 2% NaCl, basal diet + 2% MSG; basal diet + 0.125 mg/g MeHg, basal diet + 0.125 mg/g MeHg + 2% NaCl; and basal diet + 0.125 mg/g MeHg + 2% MSG for 21 days. Behavioral parameters such as distance traveled, immobility and turn angle were automatically measured using ANY-maze video tracking software (Stoelting, CO, USA). Biochemical end-points such as acetylcholinesterase (AChE), glutathione-S-transferase (GST), total thiol and TBARS were also evaluated. Results show that MeHg + NaCl, increased distance traveled while MeHg + MSG increased time immobile. AChE activity was significantly reduced in cockroaches across all the groups when compared to the control. There was no significant alteration in GST activity and total thiol levels. It could be that both NaCl and MSG potentiates the neurotoxic effect of MeHg in cockroaches.
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Affiliation(s)
- Blessing A Afolabi
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas (CCNE), Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil; Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil; Department of Biochemistry, Bowen University Iwo, Osun State, Nigeria
| | - Isaac A Adedara
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Diogo O Souza
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil
| | - João B T Rocha
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas (CCNE), Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
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Network-Based Approach to Identify Potential Targets and Drugs that Promote Neuroprotection and Neurorepair in Acute Ischemic Stroke. Sci Rep 2017; 7:40137. [PMID: 28054643 PMCID: PMC5215297 DOI: 10.1038/srep40137] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Accepted: 11/30/2016] [Indexed: 01/17/2023] Open
Abstract
Acute ischemic stroke (AIS) accounts for more than 80% of the approximately 610,000 new stroke cases worldwide every year. Both ischemia and reperfusion can cause death, damage, and functional changes of affected nerve cells, and these alterations can result in high rates of disability and mortality. Therefore, therapies aimed at increasing neuroprotection and neurorepair would make significant contributions to AIS management. However, with regard to AIS therapies, there is currently a large gap between experimental achievements and practical clinical solutions (EC-GAP-AIS). Here, by integrating curated disease-gene associations and interactome network known to be related to AIS, we investigated the molecular network mechanisms of multi-module structures underlying AIS, which might be relevant to the time frame subtypes of AIS. In addition, the EC-GAP-AIS phenomenon was confirmed and elucidated by the shortest path lengths and the inconsistencies in the molecular functionalities and overlapping pathways between AIS-related genes and drug targets. Furthermore, we identified 23 potential targets (e.g. ADORA3, which is involved in the regulation of cellular reprogramming and the extracellular matrix) and 46 candidate drugs (e.g. felbamate, methylphenobarbital and memantine) that may have value for the treatment of AIS.
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Ke T, Li R, Chen W. Inhibition of the NMDA receptor protects the rat sciatic nerve against ischemia/reperfusion injury. Exp Ther Med 2016; 11:1563-1572. [PMID: 27168774 PMCID: PMC4840580 DOI: 10.3892/etm.2016.3148] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 11/25/2015] [Indexed: 12/23/2022] Open
Abstract
Inhibition of the N-methyl-D-aspartate (NMDA) receptor by MK-801 reduces ischemia/reperfusion (I/R) injury in the central nervous system. However, few previous studies have evaluated the neuroprotective effects of MK-801 against peripheral I/R injury. The present study aimed to investigate the protective effects of MK-801 pretreatment against I/R injury in the rat sciatic nerve (SN). Sprague-Dawley rats were subjected to a sham surgery (n=8) or to a 5-h ischemic insult by femoral artery clamping (I/R and I/R+MK-801 groups; n=48 per group). I/R+MK-801 rats were intraperitoneally injected with MK-801 (0.5 ml or 1 mg/kg) at 15 min prior to reperfusion. The rats were sacrificed at 0, 6, 12, 24, 72 h, or 7 days following reperfusion. Plasma malondialdehyde (MDA) and nitric oxide (NO) concentrations, and SN inducible NO synthase (iNOS) protein expression levels, were measured using colorimetry. In addition, the protein expression levels of tumor necrosis factor-α (TNF-α) were measured using immunohistochemistry, and histological analyses of the rat SN were conducted using light and electron microscopy. Alterations in the mRNA expression levels of TNF-α and TNF-α converting enzyme (TACE) in the rat SN were detected using reverse transcription-quantitative polymerase chain reaction. In the I/R group, plasma concentrations of NO (175.3±4.2 µmol/l) and MDA (16.2±1.9 mmol/l), and the levels of iNOS (2.5±0.3) in the SN, peaked at 24 h post-reperfusion. At 24 h, pretreatment with MK-801 significantly reduced plasma NO (107.3±3.6 µmol/l) and MDA (11.8±1.6 mmol/l), and SN iNOS (1.65±0.2) levels (all P<0.01). The mRNA expression levels of TNF-α and TACE in the SN were significantly reduced in the I/R+MK-801 group, as compared with the I/R group (P<0.05). Furthermore, MK-801 pretreatment was shown to have alleviated histological signs of I/R injury, including immune cell infiltration and axon demyelination. The results of the present study suggested that pretreatment with MK-801 may alleviate I/R injury of the SN by inhibiting the activation of TNF-α and reducing the levels of iNOS in the SN.
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Affiliation(s)
- Tie Ke
- Department of Emergency Surgery, Fujian Provincial Hospital, Fujian Medical University, Fuzhou, Fujian 350001, P.R. China; Emergency Center of Fujian Province, Fujian Medical University, Fuzhou, Fujian 350001, P.R. China; Provincial Clinical Medical College, Fujian Medical University, Fuzhou, Fujian 350001, P.R. China
| | - Renbin Li
- Department of Orthopedics, The Affiliated Fuzhou Second Hospital, Xiamen University, Fuzhou, Fujian 350007, P.R. China
| | - Wenchang Chen
- Department of Emergency Surgery, Fujian Provincial Hospital, Fujian Medical University, Fuzhou, Fujian 350001, P.R. China
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Cabrera-Pastor A, Taoro L, Llansola M, Felipo V. Roles of the NMDA Receptor and EAAC1 Transporter in the Modulation of Extracellular Glutamate by Low and High Affinity AMPA Receptors in the Cerebellum in Vivo: Differential Alteration in Chronic Hyperammonemia. ACS Chem Neurosci 2015; 6:1913-21. [PMID: 26428532 DOI: 10.1021/acschemneuro.5b00212] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The roles of high- and low-affinity AMPA receptors in modulating extracellular glutamate in the cerebellum remain unclear. Altered glutamatergic neurotransmission is involved in neurological alterations in hyperammonemia, which differently affects high- and low-affinity AMPA receptors. The aims were to assess by in vivo microdialysis (a) the effects of high- and low-affinity AMPA receptor activation on extracellular glutamate in the cerebellum; (b) whether chronic hyperammonemia alters extracellular glutamate modulation by high- and/or low-affinity AMPA receptors; and (c) the contribution of NMDA receptors and EAAC1 transporter to AMPA-induced changes in extracellular glutamate. In control rats, high affinity receptor activation does not affect extracellular glutamate but increases glutamate if NMDA receptors are blocked. Low affinity AMPA receptor activation increases transiently extracellular glutamate followed by reduction below basal levels and return to basal values. The reduction is associated with transient increased membrane expression of EAAC1 and is prevented by blocking NMDA receptors. Blocking NMDA receptors with MK-801 induces a transient increase in extracellular glutamate which is associated with reduced membrane expression of EAAC1 followed by increased membrane expression of the glutamate transporter GLT-1. Chronic hyperammonemia does not affect responses to activation of low affinity AMPA receptors. Activation of high affinity AMPA receptors increases extracellular glutamate in hyperammonemic rats by an NMDA receptor-dependent mechanism. In conclusion, these results show that there is a tightly controlled interplay between AMPA and NMDA receptors and an EAAC1 transporter in controlling extracellular glutamate. Hyperammonemia alters high- but not low-affinity AMPA receptors.
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Affiliation(s)
- Andrea Cabrera-Pastor
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Calle Eduardo Primo Yufera, 3, 46012 Valencia, Spain
| | - Lucas Taoro
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Calle Eduardo Primo Yufera, 3, 46012 Valencia, Spain
| | - Marta Llansola
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Calle Eduardo Primo Yufera, 3, 46012 Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Calle Eduardo Primo Yufera, 3, 46012 Valencia, Spain
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16
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Fang XQ, Qiao H, Groveman BR, Feng S, Pflueger M, Xin WK, Ali MK, Lin SX, Xu J, Duclot F, Kabbaj M, Wang W, Ding XS, Santiago-Sim T, Jiang XH, Salter MW, Yu XM. Regulated internalization of NMDA receptors drives PKD1-mediated suppression of the activity of residual cell-surface NMDA receptors. Mol Brain 2015; 8:75. [PMID: 26584860 PMCID: PMC4653853 DOI: 10.1186/s13041-015-0167-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 11/13/2015] [Indexed: 12/13/2022] Open
Abstract
Background Constitutive and regulated internalization of cell surface proteins has been extensively investigated. The regulated internalization has been characterized as a principal mechanism for removing cell-surface receptors from the plasma membrane, and signaling to downstream targets of receptors. However, so far it is still not known whether the functional properties of remaining (non-internalized) receptor/channels may be regulated by internalization of the same class of receptor/channels. The N-methyl-D-aspartate receptor (NMDAR) is a principal subtype of glutamate-gated ion channel and plays key roles in neuronal plasticity and memory functions. NMDARs are well-known to undergo two types of regulated internalization – homologous and heterologous, which can be induced by high NMDA/glycine and DHPG, respectively. In the present work, we investigated effects of regulated NMDAR internalization on the activity of residual cell-surface NMDARs and neuronal functions. Results In electrophysiological experiments we discovered that the regulated internalization of NMDARs not only reduced the number of cell surface NMDARs but also caused an inhibition of the activity of remaining (non-internalized) surface NMDARs. In biochemical experiments we identified that this functional inhibition of remaining surface NMDARs was mediated by increased serine phosphorylation of surface NMDARs, resulting from the activation of protein kinase D1 (PKD1). Knockdown of PKD1 did not affect NMDAR internalization but prevented the phosphorylation and inhibition of remaining surface NMDARs and NMDAR-mediated synaptic functions. Conclusion These data demonstrate a novel concept that regulated internalization of cell surface NMDARs not only reduces the number of NMDARs on the cell surface but also causes an inhibition of the activity of remaining surface NMDARs through intracellular signaling pathway(s). Furthermore, modulating the activity of remaining surface receptors may be an effective approach for treating receptor internalization-induced changes in neuronal functions of the CNS. Electronic supplementary material The online version of this article (doi:10.1186/s13041-015-0167-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xiao-Qian Fang
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA.
| | - Haifa Qiao
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA.
| | - Bradley R Groveman
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA.
| | - Shuang Feng
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA.
| | - Melissa Pflueger
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA.
| | - Wen-Kuan Xin
- Faculty of Dentistry, University of Toronto, Toronto, M5G 1G6, Canada.
| | - Mohammad K Ali
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA.
| | - Shuang-Xiu Lin
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA.
| | - Jindong Xu
- Faculty of Dentistry, University of Toronto, Toronto, M5G 1G6, Canada.
| | - Florian Duclot
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA.
| | - Mohamed Kabbaj
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA.
| | - Wei Wang
- Department of Neurology, 1st Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, PR China.
| | - Xin-Sheng Ding
- Department of Neurology, 1st Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, PR China. .,BenQ Neurological Institute, Nanjing Medical University, Nanjing, 210021, PR China.
| | - Teresa Santiago-Sim
- Department of Neurosurgery, The University of Texas Medical School at Houston Vivian L. Smith, Houston, TX, 77030, USA.
| | - Xing-Hong Jiang
- Department of Physiology and Neurobiology, Medical College of Soochow University, Suzhou, 215123, China.
| | - Michael W Salter
- Program in Neuroscience and Mental Health, Hospital for Sick Children, University of Toronto, Toronto, M5G 1X8, Canada.
| | - Xian-Min Yu
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306, USA. .,Faculty of Dentistry, University of Toronto, Toronto, M5G 1G6, Canada. .,BenQ Neurological Institute, Nanjing Medical University, Nanjing, 210021, PR China. .,Department of Physiology and Neurobiology, Medical College of Soochow University, Suzhou, 215123, China.
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17
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Li S, Wang SU, Guo ZG, Huang N, Zhao FR, Zhu ML, Ma LJ, Liang JY, Zhang YL, Huang ZL, Wan GR. Protective effect of Xingnaojia formulation on rats with brain and liver damage caused by chronic alcoholism. Exp Ther Med 2015; 10:1643-1652. [PMID: 26640531 PMCID: PMC4665616 DOI: 10.3892/etm.2015.2773] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 07/31/2015] [Indexed: 01/08/2023] Open
Abstract
The aim of this study was to observe the effect of a formulation of traditional Chinese medicine extracts known as Xingnaojia (XNJ) on the liver function, learning ability and memory of rats with chronic alcoholism and to verify the mechanism by which it protects the brain and liver. A rat model of chronic alcoholism was used in the study. The spatial learning ability and memory of the rats were tested. The rats were then sacrificed and their brains and hepatic tissues were isolated. The activity of superoxide dismutase (SOD) and levels of glutamate (Glu), N-methyl D-aspartate receptor subtype 2B (NR2B), cyclin-dependent kinase 5 (CDK5) and cannabinoid receptor 1 (CB1) in the hippocampus were analyzed. The ultrastructure of the hepatic tissue was observed by electron microscopy. In addition, the activities of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) in serum were tested and the levels of low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG) and total cholesterol (TCHOL) were analyzed. XNJ enhanced the learning and memory of rats with chronic alcoholism. Treatment with XNJ increased the activity of SOD, and decreased the expression levels of NR2B mRNA and NR2B, CB1 and CDK5 proteins in the brain tissues compared with those in the model rats. It also increased the activity of ALDH in the serum and liver, decreased the serum levels of LDL, TG and TCHOL and increased the serum level of HDL. These results indicate that XNJ exhibited a protective effect against brain and liver damage in rats with chronic alcoholism.
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Affiliation(s)
- Shuang Li
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - S U Wang
- College of Pharmacy, The Third Affiliated Hospital, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Zhi-Gang Guo
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Ning Huang
- College of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Fan-Rong Zhao
- College of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Mo-Li Zhu
- College of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Li-Juan Ma
- College of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Jin-Ying Liang
- College of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Yu-Lin Zhang
- College of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Zhong-Lin Huang
- College of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Guang-Rui Wan
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
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18
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Interactive HIV-1 Tat and morphine-induced synaptodendritic injury is triggered through focal disruptions in Na⁺ influx, mitochondrial instability, and Ca²⁺ overload. J Neurosci 2014; 34:12850-64. [PMID: 25232120 DOI: 10.1523/jneurosci.5351-13.2014] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Synaptodendritic injury is thought to underlie HIV-associated neurocognitive disorders and contributes to exaggerated inflammation and cognitive impairment seen in opioid abusers with HIV-1. To examine events triggering combined transactivator of transcription (Tat)- and morphine-induced synaptodendritic injury systematically, striatal neuron imaging studies were conducted in vitro. These studies demonstrated nearly identical pathologic increases in dendritic varicosities as seen in Tat transgenic mice in vivo. Tat caused significant focal increases in intracellular sodium ([Na(+)]i) and calcium ([Ca(2+)]i) in dendrites that were accompanied by the emergence of dendritic varicosities. These effects were largely, but not entirely, attenuated by the NMDA and AMPA receptor antagonists MK-801 and CNQX, respectively. Concurrent morphine treatment accelerated Tat-induced focal varicosities, which were accompanied by localized increases in [Ca(2+)]i and exaggerated instability in mitochondrial inner membrane potential. Importantly, morphine's effects were prevented by the μ-opioid receptor antagonist CTAP and were not observed in neurons cultured from μ-opioid receptor knock-out mice. Combined Tat- and morphine-induced initial losses in ion homeostasis and increases in [Ca(2+)]i were attenuated by the ryanodine receptor inhibitor ryanodine, as well as pyruvate. In summary, Tat induced increases in [Na(+)]i, mitochondrial instability, excessive Ca(2+) influx through glutamatergic receptors, and swelling along dendrites. Morphine, acting via μ-opioid receptors, exacerbates these excitotoxic Tat effects at the same subcellular locations by mobilizing additional [Ca(2+)]i and by further disrupting [Ca(2+)]i homeostasis. We hypothesize that the spatiotemporal relationship of μ-opioid and aberrant AMPA/NMDA glutamate receptor signaling is critical in defining the location and degree to which opiates exacerbate the synaptodendritic injury commonly observed in neuroAIDS.
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19
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Huang H, Benzonana LL, Zhao H, Watts HR, Perry NJS, Bevan C, Brown R, Ma D. Prostate cancer cell malignancy via modulation of HIF-1α pathway with isoflurane and propofol alone and in combination. Br J Cancer 2014; 111:1338-49. [PMID: 25072260 PMCID: PMC4183852 DOI: 10.1038/bjc.2014.426] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 05/23/2014] [Accepted: 07/03/2014] [Indexed: 12/17/2022] Open
Abstract
Background: Surgery is considered to be the first line treatment for solid tumours. Recently, retrospective studies reported that general anaesthesia was associated with worse long-term cancer-free survival when compared with regional anaesthesia. This has important clinical implications; however, the mechanisms underlying those observations remain unclear. We aim to investigate the effect of anaesthetics isoflurane and propofol on prostate cancer malignancy. Methods: Prostate cancer (PC3) cell line was exposed to commonly used anaesthetic isoflurane and propofol. Malignant potential was assessed through evaluation of expression level of hypoxia-inducible factor-1α (HIF-1α) and its downstream effectors, cell proliferation and migration as well as development of chemoresistance. Results: We demonstrated that isoflurane, at a clinically relevant concentration induced upregulation of HIF-1α and its downstream effectors in PC3 cell line. Consequently, cancer cell characteristics associated with malignancy were enhanced, with an increase of proliferation and migration, as well as development of chemoresistance. Inhibition of HIF-1α neosynthesis through upper pathway blocking by a PI-3K-Akt inhibitor or HIF-1α siRNA abolished isoflurane-induced effects. In contrast, the intravenous anaesthetic propofol inhibited HIF-1α activation induced by hypoxia or CoCl2. Propofol also prevented isoflurane-induced HIF-1α activation, and partially reduced cancer cell malignant activities. Conclusions: Our findings suggest that modulation of HIF-1α activity by anaesthetics may affect cancer recurrence following surgery. If our data were to be extrapolated to the clinical setting, isoflurane but not propofol should be avoided for use in cancer surgery. Further work involving in vivo models and clinical trials is urgently needed to determine the optimal anaesthetic regimen for cancer patients.
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Affiliation(s)
- H Huang
- 1] Section of Anaesthetics, Pain Medicine and Intensive Care, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, London, UK [2] Department of Anesthesiology, West China Second Hospital, Sichuan University, Chengdu, China
| | - L L Benzonana
- Section of Anaesthetics, Pain Medicine and Intensive Care, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, London, UK
| | - H Zhao
- Section of Anaesthetics, Pain Medicine and Intensive Care, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, London, UK
| | - H R Watts
- Section of Anaesthetics, Pain Medicine and Intensive Care, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, London, UK
| | - N J S Perry
- Section of Anaesthetics, Pain Medicine and Intensive Care, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, London, UK
| | - C Bevan
- Division of Cancer, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, UK
| | - R Brown
- Division of Cancer, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, UK
| | - D Ma
- Section of Anaesthetics, Pain Medicine and Intensive Care, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, London, UK
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20
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Grasselli G, Rossi S, Musella A, Gentile A, Loizzo S, Muzio L, Di Sanza C, Errico F, Musumeci G, Haji N, Fresegna D, Sepman H, De Chiara V, Furlan R, Martino G, Usiello A, Mandolesi G, Centonze D. Abnormal NMDA receptor function exacerbates experimental autoimmune encephalomyelitis. Br J Pharmacol 2013; 168:502-17. [PMID: 22924679 DOI: 10.1111/j.1476-5381.2012.02178.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Revised: 08/04/2012] [Accepted: 08/13/2012] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Glutamate transmission is dysregulated in both multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE), the animal model of MS. A characteristic of EAE is increased glutamate transmission associated with up-regulation of AMPA receptors. However, little is known about the role of NMDA receptors in the synaptic modifications induced by EAE. EXPERIMENTAL APPROACH The contribution of NMDA receptors to the alterations of glutamate transmission and disease severity in EAE mice was assessed by means of neurophysiological, morphological, Western blot, metabolic and clinical score assessments. KEY RESULTS In our EAE mice, there was an NMDA receptor-dependent increase of glutamate release, associated with marked activation of the astroglia. Presynaptic NMDA receptors became overactive during EAE, increasing synaptic glutamate release by a mechanism dependent on voltage-gated sodium channels. By means of NAD(P)H autofluorescence analysis, we also found that EAE has a glutamate and NMDA receptor-dependent dysfunction of mitochondrial activity, which is known to contribute to the neurodegenerative damage of MS and EAE. Furthermore, pharmacological blockade of NMDA receptors in vivo ameliorated both synaptic transmission defects and of the clinical disease course of EAE mice, while EAE induced in mice with a genetically enhanced NMDA receptor signalling had opposite effects. CONCLUSIONS AND IMPLICATIONS Our data, showing both sensitization of NMDA receptors and their involvement in the progression of the EAE disease, supggest that pharmacological impairment of NMDA receptor signalling would be a component of a neuroprotection strategy in MS.
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Affiliation(s)
- G Grasselli
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), Università Tor Vergata, Rome, Italy
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21
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Xie YF, Pflueger M, Feng S, Lin SX, Kwan CL, Galasko G, Sessle BJ, Yu XM. Locally released small (non-protein) ninhydrin-reacting molecules underlie developmental differences of cultured medullary versus spinal dorsal horn neurons. J Neurochem 2012; 122:605-18. [PMID: 22612377 DOI: 10.1111/j.1471-4159.2012.07797.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Neurons located in the trigeminal subnucleus caudalis (Vc) play crucial roles in pain and sensorimotor functions in the orofacial region. Because of many anatomical and functional similarities with the spinal dorsal horn (SDH), Vc has been termed the medullary dorsal horn--analogous to the SDH. Here, we report that when compared with embryonic SDH neurons in culture, neurons isolated from the Vc region showed significantly slower growth, lower glutamate receptor activity, and more cells undergoing cell death. SDH neuron development was inhibited in co-cultures of SDH and Vc tissues while Vc neuron development was promoted by co-culture with SDH tissues. Furthermore, we identified that small (non-protein) ninhydrin-reacting molecules purified from either embryonic or post-natal Vc-conditioned medium inhibited neuronal growth whereas ninhydrin-reacting molecules from SDH-conditioned medium promoted neuronal growth. These findings suggest the involvement of locally released factors in the region-specific regulation of neuronal development in Vc and SDH, central nervous system regions playing critical roles in pain, and point to novel avenues for investigating central nervous system regionalization and for designing therapeutic approaches to manage neurodegenerative diseases and pain.
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Affiliation(s)
- Yu-Feng Xie
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida 32306, USA
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22
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Cabrera-Pastor A, Llansola M, Reznikov V, Boix J, Felipo V. Differential effects of chronic hyperammonemia on modulation of the glutamate-nitric oxide-cGMP pathway by metabotropic glutamate receptor 5 and low and high affinity AMPA receptors in cerebellum in vivo. Neurochem Int 2012; 61:63-71. [PMID: 22521775 DOI: 10.1016/j.neuint.2012.04.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 03/27/2012] [Accepted: 04/05/2012] [Indexed: 01/06/2023]
Abstract
Previous studies show that chronic hyperammonemia impairs learning ability of rats by impairing the glutamate-nitric oxide (NO)-cyclic guanosine mono-phosphate (cGMP) pathway in cerebellum. Three types of glutamate receptors cooperate in modulating the NO-cGMP pathway: metabotropic glutamate receptor 5 (mGluR5), (RS)-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl-d-aspartic acid (NMDA) receptors. The aim of this work was to assess whether hyperammonemia alters the modulation of this pathway by mGluR5 and AMPA receptors in cerebellum in vivo. The results support that in control rats: (1) low AMPA concentrations (0.1mM) activate nearly completely Ca(2+)-permeable (glutamate receptor subunit 2 (GluR2)-lacking) AMPA receptors and the NO-cGMP pathway; (2) higher AMPA concentrations (0.3 mM) also activate Ca(2+)-impermeable (GluR2-containing) AMPA receptors, leading to activation of NMDA receptors and of NO-cGMP pathway. Moreover, the data support that chronic hyperammonemia: (1) reduces glutamate release and activation of the glutamate-NO-cGMP pathway by activation of mGluR5; (2) strongly reduces the direct activation by AMPA receptors of the NO-cGMP pathway, likely due to reduced entry of Ca(2+) through GluR2-lacking, high affinity AMPA receptors; (3) strongly increases the indirect activation of the NO-cGMP pathway by high affinity AMPA receptors, likely due to increased entry of Na(+) through GluR2-lacking AMPA receptors and NMDA receptors activation; (4) reduces the indirect activation of the NO-cGMP pathway by low affinity AMPA receptors, likely due to reduced activation of NMDA receptors.
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Affiliation(s)
- Andrea Cabrera-Pastor
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Av. Autopista del Saler, 16, 46012 Valencia, Spain.
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Modulation of nickel-induced bursting with 4-aminopyridine in leech retzius nerve cells. ARCH BIOL SCI 2010. [DOI: 10.2298/abs1004035p] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Paroxysmal depolarization shift has been identified as a characteristic
feature of the cellular basis of epilepsy. On Na+-dependent bursting, 1
mmol/l 4-aminopyridine (4-AP) produced a two-phase effect - a significant
depolarization accompanied by an increase in the frequency of bursting,
followed by repolarization along with a diminished frequency of bursting.
Neither 1 ?mol/l apamin nor 150 nmol/l charybdotoxin (ChTX) elicited any
significant effect on either bursting or standard conditions. Our results
suggest that 4-AP affects the bursting indirectly by altering the
excitability of the cell. The lack of effects of apamin and ChTX is probably
due to channel insensitivity to these blockers in leech.
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Yu XM, Groveman BR, Fang XQ, Lin SX. THE ROLE OF INTRACELLULAR SODIUM (Na) IN THE REGULATION OF CALCIUM (Ca)-MEDIATED SIGNALING AND TOXICITY. Health (London) 2010; 2:8-15. [PMID: 21243124 DOI: 10.4236/health.2010.21002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
It is known that activated N-methyl-D-aspartate receptors (NMDARs) are a major route of excessive calcium ion (Ca(2+)) entry in central neurons, which may activate degradative processes and thereby cause cell death. Therefore, NMDARs are now recognized to play a key role in the development of many diseases associated with injuries to the central nervous system (CNS). However, it remains a mystery how NMDAR activity is recruited in the cellular processes leading to excitotoxicity and how NMDAR activity can be controlled at a physiological level. The sodium ion (Na(+)) is the major cation in extracellular space. With its entry into the cell, Na(+) can act as a critical intracellular second messenger that regulates many cellular functions. Recent data have shown that intracellular Na(+) can be an important signaling factor underlying the up-regulation of NMDARs. While Ca(2+) influx during the activation of NMDARs down-regulates NMDAR activity, Na(+) influx provides an essential positive feedback mechanism to overcome Ca(2+)-induced inhibition and thereby potentiate both NMDAR activity and inward Ca(2+) flow. Extensive investigations have been conducted to clarify mechanisms underlying Ca(2+)-mediated signaling. This review focuses on the roles of Na(+) in the regulation of Ca(2+)-mediated NMDAR signaling and toxicity.
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Affiliation(s)
- Xian-Min Yu
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, Florida, 32306-4300, USA
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Jabba SV, Prakash A, Dravid SM, Gerwick WH, Murray TF. Antillatoxin, a novel lipopeptide, enhances neurite outgrowth in immature cerebrocortical neurons through activation of voltage-gated sodium channels. J Pharmacol Exp Ther 2009; 332:698-709. [PMID: 20026674 DOI: 10.1124/jpet.109.161802] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Antillatoxin (ATX) is a structurally novel lipopeptide that activates voltage-gated sodium channels (VGSC) leading to sodium influx in cerebellar granule neurons and cerebrocortical neurons 8 to 9 days in vitro (Li et al., 2001; Cao et al., 2008). However, the precise recognition site for ATX on the VGSC remains to be defined. Inasmuch as elevation of intracellular sodium ([Na(+)](i)) may increase N-methyl-d-aspartate receptor (NMDAR)-mediated Ca(2+) influx, Na(+) may function as a signaling molecule. We hypothesized that ATX may enhance neurite outgrowth in cerebrocortical neurons by elevating [Na(+)](i) and augmenting NMDAR function. ATX (30-100 nM) robustly stimulated neurite outgrowth, and this enhancement was sensitive to the VGSC antagonist, tetrodotoxin. To unambiguously demonstrate the enhancement of NMDA receptor function by ATX, we recorded single-channel currents from cell-attached patches. ATX was found to increase the open probability of NMDA receptors. Na(+)-dependent up-regulation of NMDAR function has been shown to be regulated by Src family kinase (SFK) (Yu and Salter, 1998). The Src kinase inhibitor PP2 abrogated ATX-enhanced neurite outgrowth, suggesting a SFK involvement in this response. ATX-enhanced neurite outgrowth was also inhibited by the NMDAR antagonist, (5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (MK-801), and the calmodulin-dependent kinase kinase (CaMKK) inhibitor, 1,8-naphthoylene benzimidazole-3-carboxylic acid (STO-609), demonstrating the requirement for NMDAR activation with subsequent downstream engagement of the Ca(2+)-dependent CaMKK pathway. These results with the structurally and mechanistically novel natural product, ATX, confirm and generalize our earlier results with a neurotoxin site 5 ligand. These data suggest that VGSC activators may represent a novel pharmacological strategy to regulate neuronal plasticity through NMDAR-dependent mechanisms.
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Affiliation(s)
- S V Jabba
- Creighton University School of Medicine, Department of Pharmacology, Omaha, NE 68178, USA
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26
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Sodium channel activation augments NMDA receptor function and promotes neurite outgrowth in immature cerebrocortical neurons. J Neurosci 2009; 29:3288-301. [PMID: 19279266 DOI: 10.1523/jneurosci.6104-08.2009] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
A range of extrinsic signals, including afferent activity, affect neuronal growth and plasticity. Neuronal activity regulates intracellular Ca(2+), and activity-dependent calcium signaling has been shown to regulate dendritic growth and branching (Konur and Ghosh, 2005). NMDA receptor (NMDAR) stimulation of Ca(2+)/calmodulin-dependent protein kinase signaling cascades has, moreover, been demonstrated to regulate neurite/axonal outgrowth (Wayman et al., 2004). We used a sodium channel activator, brevetoxin (PbTx-2), to explore the relationship between intracellular [Na(+)] and NMDAR-dependent development. PbTx-2 alone, at a concentration of 30 nM, did not affect Ca(2+) dynamics in 2 d in vitro cerebrocortical neurons; however, this treatment robustly potentiated NMDA-induced Ca(2+) influx. The 30 nM PbTx-2 treatment produced a maximum [Na(+)](i) of 16.9 +/- 1.5 mM, representing an increment of 8.8 +/- 1.8 mM over basal. The corresponding membrane potential change produced by 30 nM PbTx-2 was modest and, therefore, insufficient to relieve the voltage-dependent Mg(2+) block of NMDARs. To unambiguously demonstrate the enhancement of NMDA receptor function by PbTx-2, we recorded single-channel currents from cell-attached patches. PbTx-2 treatment was found to increase both the mean open time and open probability of NMDA receptors. These effects of PbTx-2 on NMDA receptor function were dependent on extracellular Na(+) and activation of Src kinase. The functional consequences of PbTx-2-induced enhancement of NMDAR function were evaluated in immature cerebrocortical neurons. PbTx-2 concentrations between 3 and 300 nM enhanced neurite outgrowth. Voltage-gated sodium channel activators may accordingly represent a novel pharmacologic strategy to regulate neuronal plasticity through an NMDA receptor and Src family kinase-dependent mechanism.
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27
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Abstract
Taurine, an important mediator of cellular volume regulation in the central nervous system, is accumulated into neurons and glia by means of a highly specific sodium-dependent membrane transporter. During hyperosmotic cell shrinkage, net cellular taurine content increases as taurine transporter activity is enhanced via elevated gene expression of the transporter protein. In hypo-osmotic conditions, taurine is rapidly lost from cells by means of taurine-conducting membrane channels. We reasoned that changes in taurine transporter activity also might accompany cell swelling to minimize re-accumulation of taurine from the extracellular space. Thus, we determined the kinetic and pharmacological characteristics of neuronal taurine transport and the response to osmotic swelling. Accumulation of radioactive taurine is strongly temperature dependent and occurs via saturable and non-saturable pathways. At concentrations of taurine expected in extracellular fluid in vivo, 98% of taurine accumulation would occur via the saturable pathway. This pathway obeys Michaelis-Menten kinetics with a Km of 30.0 +/- 8.8 microm (mean +/- SE) and Jmax of 2.1 +/- 0.2 nmol/mg protein min. The saturable pathway is dependent on extracellular sodium with an effective binding constant of 80.0 +/- 3.1 mm and a Hill coefficient of 2.1 +/- 0.1. This pathway is inhibited by structural analogues of taurine and by the anion channel inhibitors, 4,4'-diisothiocyanostilbene-2, 2'-disulfonic acid (DIDS) and 5-nitro-2-(3 phenylpropylamino) benzoic acid (NPPB). NPPB, but not DIDS, also reduces the ATP content of the cell cultures. Osmotic swelling at constant extracellular sodium concentration reduces the Jmax of the saturable transport pathway by approximately 48%, increases Kdiff for the non-saturable pathway by 77%, but has no effect on cellular ATP content. These changes in taurine transport occurring in swollen neurons in vivo would contribute to net reduction of taurine content and resulting volume regulation.
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Affiliation(s)
- James E Olson
- Department of Emergency Medicine, Wright State University School of Medicine, Cox Institute, Kettering, Ohio 45429, USA.
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28
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Xin WK, Zhao XH, Xu J, Lei G, Kwan CL, Zhu KM, Cho JS, Duff M, Ellen RP, McCulloch CAG, Yu XM. The removal of extracellular calcium: a novel mechanism underlying the recruitment of N-methyl-d-aspartate (NMDA) receptors in neurotoxicity. Eur J Neurosci 2005; 21:622-36. [PMID: 15733081 DOI: 10.1111/j.1460-9568.2005.03888.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The involvement of NMDA-type glutamate receptor in neuronal injury established in experimental stroke and neurotrauma models has been recently challenged by failures in treatment of stroke/neurotrauma patients with NMDA receptor antagonists. NMDA receptor activity is known to be essential for mediating a multitude of physiological functions. However, how NMDA receptors are recruited to cause neuronal injury remains unclear. Here we report that the time period during which initial NMDA receptor up-regulation occurs is critical for the recruitment of NMDA receptors causing neuronal injury during extracellular calcium (Ca2+) reperfusion in cultured hippocampal neurons, and represents the key period for neuronal protection by NMDA receptor antagonists. Furthermore, we identified that via intracellular sodium (Na+), extracellular Ca2+ depletion induces the up-regulation of NMDA receptor gating. Taken together, our study provides direct experimental evidence suggesting that determination of when and how NMDA receptors are recruited to cause neurotoxicity is essential for guiding treatment via antagonism of NMDA receptor functions.
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Affiliation(s)
- Wen-Kuan Xin
- Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
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