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Patel JC, Sherpa AD, Melani R, Witkovsky P, Wiseman MR, O'Neill B, Aoki C, Tritsch NX, Rice ME. GABA co-released from striatal dopamine axons dampens phasic dopamine release through autoregulatory GABA A receptors. Cell Rep 2024; 43:113834. [PMID: 38431842 PMCID: PMC11089423 DOI: 10.1016/j.celrep.2024.113834] [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: 10/05/2022] [Revised: 11/29/2023] [Accepted: 02/05/2024] [Indexed: 03/05/2024] Open
Abstract
Striatal dopamine axons co-release dopamine and gamma-aminobutyric acid (GABA), using GABA provided by uptake via GABA transporter-1 (GAT1). Functions of GABA co-release are poorly understood. We asked whether co-released GABA autoinhibits dopamine release via axonal GABA type A receptors (GABAARs), complementing established inhibition by dopamine acting at axonal D2 autoreceptors. We show that dopamine axons express α3-GABAAR subunits in mouse striatum. Enhanced dopamine release evoked by single-pulse optical stimulation in striatal slices with GABAAR antagonism confirms that an endogenous GABA tone limits dopamine release. Strikingly, an additional inhibitory component is seen when multiple pulses are used to mimic phasic axonal activity, revealing the role of GABAAR-mediated autoinhibition of dopamine release. This autoregulation is lost in conditional GAT1-knockout mice lacking GABA co-release. Given the faster kinetics of ionotropic GABAARs than G-protein-coupled D2 autoreceptors, our data reveal a mechanism whereby co-released GABA acts as a first responder to dampen phasic-to-tonic dopamine signaling.
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Affiliation(s)
- Jyoti C Patel
- Department of Neurosurgery, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA.
| | - Ang D Sherpa
- Department of Neurosurgery, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA; Center for Neural Science New York University, 4 Washington Place, New York, NY 10003, USA
| | - Riccardo Melani
- NYU Neuroscience Institute, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Paul Witkovsky
- Department of Neurosurgery, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Madeline R Wiseman
- Department of Neurosurgery, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Brian O'Neill
- Department of Neurosurgery, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Chiye Aoki
- NYU Neuroscience Institute, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA; Center for Neural Science New York University, 4 Washington Place, New York, NY 10003, USA
| | - Nicolas X Tritsch
- NYU Neuroscience Institute, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Margaret E Rice
- Department of Neurosurgery, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA; NYU Neuroscience Institute, New York University Grossman School of Medicine, 550 First Avenue, New York, NY 10016, USA.
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2
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Ali DN, Ali HM, Lopez MR, Kang S, Choi DS. Astrocytic GABAergic Regulation in Alcohol Use and Major Depressive Disorders. Cells 2024; 13:318. [PMID: 38391931 PMCID: PMC10887002 DOI: 10.3390/cells13040318] [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: 11/30/2023] [Revised: 01/26/2024] [Accepted: 02/06/2024] [Indexed: 02/24/2024] Open
Abstract
Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system (CNS). Most GABAergic neurons synthesize GABA from glutamate and release it in the synaptic cleft in the CNS. However, astrocytes can also synthesize and release GABA, activating GABA receptors in the neighboring neurons in physiological and pathological conditions. As the primary homeostatic glial cells in the brain, astrocytes play a crucial role in regulating GABA homeostasis and synaptic neurotransmission. Accumulating evidence demonstrates that astrocytic GABA dysregulation is implicated in psychiatric disorders, including alcohol use disorder (AUD) and major depressive disorder (MDD), the most prevalent co-occurring psychiatric disorders. Several current medications and emerging pharmacological agents targeting GABA levels are in clinical trials for treating AUD and MDD. This review offers a concise summary of the role of astrocytic GABA regulation in AUD and MDD. We also provide an overview of the current understanding and areas of debate regarding the mechanisms by which astrocytes regulate GABA in the CNS and their potential significance in the molecular basis of AUD and MDD, paving the way toward future research directions and potential therapeutic target areas within this field.
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Affiliation(s)
- Dina N. Ali
- Department of Molecular Pharmacology and Experimental Therapeutics, Rochester, MN 55905, USA; (D.N.A.); (H.M.A.); (M.R.L.); (S.K.)
| | - Hossam M. Ali
- Department of Molecular Pharmacology and Experimental Therapeutics, Rochester, MN 55905, USA; (D.N.A.); (H.M.A.); (M.R.L.); (S.K.)
| | - Matthew R. Lopez
- Department of Molecular Pharmacology and Experimental Therapeutics, Rochester, MN 55905, USA; (D.N.A.); (H.M.A.); (M.R.L.); (S.K.)
| | - Shinwoo Kang
- Department of Molecular Pharmacology and Experimental Therapeutics, Rochester, MN 55905, USA; (D.N.A.); (H.M.A.); (M.R.L.); (S.K.)
| | - Doo-Sup Choi
- Department of Molecular Pharmacology and Experimental Therapeutics, Rochester, MN 55905, USA; (D.N.A.); (H.M.A.); (M.R.L.); (S.K.)
- Neuroscience Program, Rochester, MN 55905, USA
- Department of Psychiatry and Psychology, Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA
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3
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Eepho OI, Bashir AAM, Oniyide AA, Aturamu A, Owolabi OV, Ajadi IO, Fafure AA, Ajadi MB, Areloegbe SE, Olaniyi KS. Modulation of GABA by sodium butyrate ameliorates hypothalamic inflammation in experimental model of PCOS. BMC Neurosci 2023; 24:62. [PMID: 37996797 PMCID: PMC10666373 DOI: 10.1186/s12868-023-00834-z] [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: 08/26/2023] [Accepted: 11/13/2023] [Indexed: 11/25/2023] Open
Abstract
Polycystic ovarian syndrome (PCOS) is a known endocrine disorder that has affected many women of childbearing age, and is accompanied by various neurodegenerative conditions. Hence, this study investigates the impact of butyrate in reversing hypothalamic-related disorder, possibly through γ aminobutyric acid (GABA) in a rat model of PCOS. Eight-week-old female Wistar rats were allotted into four groups (n = 5), which include control, butyrate, letrozole, and letrozole + butyrate groups. PCOS was induced by administering 1 mg/kg of letrozole (oral gavage) for 21 days. After confirmation of PCOS, 200 mg/kg of butyrate (oral gavage) was administered for 6 weeks. Rats with PCOS were characterized by elevated levels of plasma insulin and testosterone. Increases in plasma and hypothalamic triglyceride levels, inflammatory biomarker (SDF-1), apoptotic marker (caspase-6), and decreased plasma GnRH were observed. Additionally, a decrease in hypothalamic GABA was revealed. Nevertheless, the administration of butyrate attenuated these alterations. The present study suggests that butyrate ameliorates hypothalamic inflammation in an experimental model of PCOS, a beneficial effect that is accompanied by enhanced GABA production.
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Affiliation(s)
- Oony-Iye Eepho
- Cardio/Endo-metabolic and Microbiome Research Unit, Department of Physiology, College of Medicine and Health Sciences, Afe Babalola University, P.M.B. 5454, Ado-Ekiti, 360101, Nigeria
| | - Al-Amin M Bashir
- Cardio/Endo-metabolic and Microbiome Research Unit, Department of Physiology, College of Medicine and Health Sciences, Afe Babalola University, P.M.B. 5454, Ado-Ekiti, 360101, Nigeria
| | - Adesola A Oniyide
- Cardio/Endo-metabolic and Microbiome Research Unit, Department of Physiology, College of Medicine and Health Sciences, Afe Babalola University, P.M.B. 5454, Ado-Ekiti, 360101, Nigeria
| | - Ayodeji Aturamu
- Cardio/Endo-metabolic and Microbiome Research Unit, Department of Physiology, College of Medicine and Health Sciences, Afe Babalola University, P.M.B. 5454, Ado-Ekiti, 360101, Nigeria
| | - Olutunmise V Owolabi
- Department of Biochemistry, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, 360101, Nigeria
| | - Isaac O Ajadi
- Department of Physiology, Faculty of Basic Medical Sciences, Ladoke Akintola University of Technology, Ogbomosho, Nigeria
| | - Adedamola A Fafure
- Department of Anatomy, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, 360101, Nigeria
| | - Mary B Ajadi
- Department of Chemical Pathology, College of Health Sciences, Ladoke Akintola University of Technology, Ogbomosho, Nigeria
| | - Stephanie E Areloegbe
- Cardio/Endo-metabolic and Microbiome Research Unit, Department of Physiology, College of Medicine and Health Sciences, Afe Babalola University, P.M.B. 5454, Ado-Ekiti, 360101, Nigeria
| | - Kehinde S Olaniyi
- Cardio/Endo-metabolic and Microbiome Research Unit, Department of Physiology, College of Medicine and Health Sciences, Afe Babalola University, P.M.B. 5454, Ado-Ekiti, 360101, Nigeria.
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Bhatt M, Di Iacovo A, Romanazzi T, Roseti C, Bossi E. Betaine-The dark knight of the brain. Basic Clin Pharmacol Toxicol 2023; 133:485-495. [PMID: 36735640 DOI: 10.1111/bcpt.13839] [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: 11/15/2022] [Revised: 01/20/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023]
Abstract
The role of betaine in the liver and kidney has been well documented, even from the cellular and molecular point of view. Despite literature reporting positive effects of betaine supplementation in Alzheimer's, Parkinson's and schizophrenia, the role and function of betaine in the brain are little studied and reviewed. Beneficial effects of betaine in neurodegeneration, excitatory and inhibitory imbalance and against oxidative stress in the central nervous system (CNS) have been collected and analysed to understand the main role of betaine in the brain. There are many 'dark' aspects needed to complete the picture. The understanding of how this osmolyte is transported across neuron and glial cells is also controversial, as the expression levels and functioning of the known protein capable to transport betaine expressed in the brain, betaine-GABA transporter 1 (BGT-1), is itself not well clarified. The reported actions of betaine beyond BGT-1 related to neuronal degeneration and memory impairment are the focus of this work. With this review, we underline the scarcity of detailed molecular and cellular information about betaine action. Consequently, the requirement of detailed focus on and study of the interaction of this molecule with CNS components to sustain the therapeutic use of betaine.
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Affiliation(s)
- Manan Bhatt
- Department of Biotechnology and Life Sciences, Laboratory of Cellular and Molecular Physiology, University of Insubria, Varese, Italy
- School of Experimental and Translational Medicine, University of Insubria, Varese, Italy
| | - Angela Di Iacovo
- Department of Biotechnology and Life Sciences, Laboratory of Cellular and Molecular Physiology, University of Insubria, Varese, Italy
- School of Experimental and Translational Medicine, University of Insubria, Varese, Italy
| | - Tiziana Romanazzi
- Department of Biotechnology and Life Sciences, Laboratory of Cellular and Molecular Physiology, University of Insubria, Varese, Italy
- School of Experimental and Translational Medicine, University of Insubria, Varese, Italy
| | - Cristina Roseti
- Department of Biotechnology and Life Sciences, Laboratory of Cellular and Molecular Physiology, University of Insubria, Varese, Italy
- Centre for Neuroscience, University of Insubria, Varese, Italy
| | - Elena Bossi
- Department of Biotechnology and Life Sciences, Laboratory of Cellular and Molecular Physiology, University of Insubria, Varese, Italy
- Centre for Neuroscience, University of Insubria, Varese, Italy
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5
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Torres-López C, Cuartero MI, García-Culebras A, de la Parra J, Fernández-Valle ME, Benito M, Vázquez-Reyes S, Jareño-Flores T, de Castro-Millán FJ, Hurtado O, Buckwalter MS, García-Segura JM, Lizasoain I, Moro MA. Ipsilesional Hippocampal GABA Is Elevated and Correlates With Cognitive Impairment and Maladaptive Neurogenesis After Cortical Stroke in Mice. Stroke 2023; 54:2652-2665. [PMID: 37694402 DOI: 10.1161/strokeaha.123.043516] [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: 11/01/2022] [Accepted: 08/09/2023] [Indexed: 09/12/2023]
Abstract
BACKGROUND Cognitive dysfunction is a frequent stroke sequela, but its pathogenesis and treatment remain unresolved. Involvement of aberrant hippocampal neurogenesis and maladaptive circuitry remodeling has been proposed, but their mechanisms are unknown. Our aim was to evaluate potential underlying molecular/cellular events implicated. METHODS Stroke was induced by permanent occlusion of the middle cerebral artery occlusion in 2-month-old C57BL/6 male mice. Hippocampal metabolites/neurotransmitters were analyzed longitudinally by in vivo magnetic resonance spectroscopy. Cognitive function was evaluated with the contextual fear conditioning test. Microglia, astrocytes, neuroblasts, interneurons, γ-aminobutyric acid (GABA), and c-fos were analyzed by immunofluorescence. RESULTS Approximately 50% of mice exhibited progressive post-middle cerebral artery occlusion cognitive impairment. Notably, immature hippocampal neurons in the impaired group displayed more severe aberrant phenotypes than those from the nonimpaired group. Using magnetic resonance spectroscopy, significant bilateral changes in hippocampal metabolites, such as myo-inositol or N-acetylaspartic acid, were found that correlated, respectively, with numbers of glia and immature neuroblasts in the ischemic group. Importantly, some metabolites were specifically altered in the ipsilateral hippocampus suggesting its involvement in aberrant hippocampal neurogenesis and remodeling processes. Specifically, middle cerebral artery occlusion animals with higher hippocampal GABA levels displayed worse cognitive outcome. Implication of GABA in this setting was supported by the amelioration of ischemia-induced memory deficits and aberrant hippocampal neurogenesis after blocking pharmacologically GABAergic neurotransmission, an intervention which was ineffective when neurogenesis was inhibited. These data suggest that GABA exerts its detrimental effect, at least partly, by affecting morphology and integration of newborn neurons into the hippocampal circuits. CONCLUSIONS Hippocampal GABAergic neurotransmission could be considered a novel diagnostic and therapeutic target for poststroke cognitive impairment.
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Affiliation(s)
- Cristina Torres-López
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
| | - Maria I Cuartero
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
| | - Alicia García-Culebras
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Departamento de Biología Celular, Facultad de Medicina (A.G.-C.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
| | - Juan de la Parra
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
| | - María E Fernández-Valle
- Infraestructura Científica y Técnica Singular (ICTS) Centro de Bioimagen Complutense (M.E.F.-V., J.M.G.-S.), Universidad Complutense de Madrid (UCM), Spain
| | - Marina Benito
- Hospital Nacional de Parapléjicos de Toledo, Spain (M.B.)
| | - Sandra Vázquez-Reyes
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
| | - Tania Jareño-Flores
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
| | - Francisco J de Castro-Millán
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
| | - Olivia Hurtado
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
| | - Marion S Buckwalter
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, CA (M.S.B.)
| | - Juan M García-Segura
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Infraestructura Científica y Técnica Singular (ICTS) Centro de Bioimagen Complutense (M.E.F.-V., J.M.G.-S.), Universidad Complutense de Madrid (UCM), Spain
- Departamento de Bioquímica y Biología Molecular (J.M.G.-S.), Universidad Complutense de Madrid (UCM), Spain
| | - Ignacio Lizasoain
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
| | - María A Moro
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
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Osse AML, Pandey RS, Wirt RA, Ortiz AA, Salazar A, Kimmich M, Toledano Strom EN, Oblak A, Lamb B, Hyman JM, Carter GW, Kinney J. Reduction in GABAB on glia induce Alzheimer's disease related changes. Brain Behav Immun 2023; 110:260-275. [PMID: 36906075 PMCID: PMC10115139 DOI: 10.1016/j.bbi.2023.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 02/26/2023] [Accepted: 03/01/2023] [Indexed: 03/13/2023] Open
Abstract
Alzheimer's Disease (AD) is a neurodegenerative disorder characterized by beta-amyloid plaques (Aβ), neurofibrillary tangles (NFT), and neuroinflammation. Data have demonstrated that neuroinflammation contributes to Aβ and NFT onset and progression, indicating inflammation and glial signaling is vital to understanding AD. A previous investigation demonstrated a significant decrease of the GABAB receptor (GABABR) in APP/PS1 mice (Salazar et al., 2021). To determine if changes in GABABR restricted to glia serve a role in AD, we developed a mouse model with a reduction of GABABR restricted to macrophages, GAB/CX3ert. This model exhibits changes in gene expression and electrophysiological alterations similar to amyloid mouse models of AD. Crossing the GAB/CX3ert mouse with APP/PS1 resulted in significant increases in Aβ pathology. Our data demonstrates that decreased GABABR on macrophages leads to several changes observed in AD mouse models, as well as exacerbation of AD pathology when crossed with existing models. These data suggest a novel mechanism in AD pathogenesis.
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Affiliation(s)
- Amanda M Leisgang Osse
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States.
| | - Ravi S Pandey
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, United States
| | - Ryan A Wirt
- University of Nevada, Las Vegas, Department of Psychology, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Andrew A Ortiz
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Arnold Salazar
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Michael Kimmich
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Erin N Toledano Strom
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Adrian Oblak
- Indiana University, School of Medicine, 340 W 10(th) Street, Indianapolis, IN 46202, United States
| | - Bruce Lamb
- Indiana University, School of Medicine, 340 W 10(th) Street, Indianapolis, IN 46202, United States
| | - James M Hyman
- University of Nevada, Las Vegas, Department of Psychology, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Gregory W Carter
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, United States
| | - Jefferson Kinney
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
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7
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Magloire V, Savtchenko LP, Jensen TP, Sylantyev S, Kopach O, Cole N, Tyurikova O, Kullmann DM, Walker MC, Marvin JS, Looger LL, Hasseman JP, Kolb I, Pavlov I, Rusakov DA. Volume-transmitted GABA waves pace epileptiform rhythms in the hippocampal network. Curr Biol 2023; 33:1249-1264.e7. [PMID: 36921605 PMCID: PMC10615848 DOI: 10.1016/j.cub.2023.02.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 01/05/2023] [Accepted: 02/15/2023] [Indexed: 03/17/2023]
Abstract
Mechanisms that entrain and pace rhythmic epileptiform discharges remain debated. Traditionally, the quest to understand them has focused on interneuronal networks driven by synaptic GABAergic connections. However, synchronized interneuronal discharges could also trigger the transient elevations of extracellular GABA across the tissue volume, thus raising tonic conductance (Gtonic) of synaptic and extrasynaptic GABA receptors in multiple cells. Here, we monitor extracellular GABA in hippocampal slices using patch-clamp GABA "sniffer" and a novel optical GABA sensor, showing that periodic epileptiform discharges are preceded by transient, region-wide waves of extracellular GABA. Neural network simulations that incorporate volume-transmitted GABA signals point to a cycle of GABA-driven network inhibition and disinhibition underpinning this relationship. We test and validate this hypothesis using simultaneous patch-clamp recordings from multiple neurons and selective optogenetic stimulation of fast-spiking interneurons. Critically, reducing GABA uptake in order to decelerate extracellular GABA fluctuations-without affecting synaptic GABAergic transmission or resting GABA levels-slows down rhythmic activity. Our findings thus unveil a key role of extrasynaptic, volume-transmitted GABA in pacing regenerative rhythmic activity in brain networks.
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Affiliation(s)
- Vincent Magloire
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
| | - Leonid P Savtchenko
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
| | - Thomas P Jensen
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Sergyi Sylantyev
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK; Rowett Institute, University of Aberdeen, Ashgrove Road West, Aberdeen AB25 2ZD, UK
| | - Olga Kopach
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Nicholas Cole
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Olga Tyurikova
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Dimitri M Kullmann
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Matthew C Walker
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Jonathan S Marvin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Loren L Looger
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA; Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA; GENIE Project Team, Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Jeremy P Hasseman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA; GENIE Project Team, Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Ilya Kolb
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA; GENIE Project Team, Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Ivan Pavlov
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Dmitri A Rusakov
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
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8
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Li F, Fu X, Luo X, Lin Q, Liang H, Niu Y, Liu L, Li N. Role of asparagine biosynthesis pathway in Siniperca chuatsi rhabdovirus proliferation. Front Microbiol 2023; 14:1165491. [PMID: 37065159 PMCID: PMC10102668 DOI: 10.3389/fmicb.2023.1165491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 03/15/2023] [Indexed: 04/03/2023] Open
Abstract
Viruses are non-living organisms that rely on host cellular metabolism to complete their life cycle. Siniperca chuatsi rhabdovirus (SCRV) has caused huge economic losses to the Chinese perch (Siniperca chuatsi) industry worldwide. SCRV replication is dependent on the cellular glutamine metabolism, while aspartate metabolism plays an important role in viral proliferation in glutamine deficiency. Herein, we investigated roles of asparagine metabolism in SCRV proliferation. Results showed that SCRV infection upregulated the expression of key enzymes in the aspartate metabolic pathway in CPB cells. And the key enzymes of malate-aspartic acid shuttle pathway upregulated during the virus invasion phase, and key enzymes of the asparagine biosynthesis pathway upregulated during the viral replication and release phase. When asparagine was added to the depleted medium, the SCRV copy number restored to 90% of those in replete medium, showing that asparagine and glutamine completely rescue the replication of SCRV. Moreover, inhibition of the aspartate- malate shuttle pathway and knockdown of the expression of key enzymes in the asparagine biosynthesis pathway significantly reduced SCRV production, indicating that the aspartic acid metabolic pathway was required to the replication and proliferation of SCRV. Above results provided references for elucidating pathogenic mechanism of SCRV by regulation of aspartate metabolism.
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Affiliation(s)
- Fangying Li
- College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, China
- Key Laboratory of Fishery Drug Development, Ministry of Agriculture and Rural Affairs, Guangdong Province Key Laboratory of Aquatic Animal Immune Technology, Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Xiaozhe Fu
- Key Laboratory of Fishery Drug Development, Ministry of Agriculture and Rural Affairs, Guangdong Province Key Laboratory of Aquatic Animal Immune Technology, Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Xia Luo
- Key Laboratory of Fishery Drug Development, Ministry of Agriculture and Rural Affairs, Guangdong Province Key Laboratory of Aquatic Animal Immune Technology, Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Qiang Lin
- Key Laboratory of Fishery Drug Development, Ministry of Agriculture and Rural Affairs, Guangdong Province Key Laboratory of Aquatic Animal Immune Technology, Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Hongru Liang
- Key Laboratory of Fishery Drug Development, Ministry of Agriculture and Rural Affairs, Guangdong Province Key Laboratory of Aquatic Animal Immune Technology, Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Yinjie Niu
- Key Laboratory of Fishery Drug Development, Ministry of Agriculture and Rural Affairs, Guangdong Province Key Laboratory of Aquatic Animal Immune Technology, Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Lihui Liu
- Key Laboratory of Fishery Drug Development, Ministry of Agriculture and Rural Affairs, Guangdong Province Key Laboratory of Aquatic Animal Immune Technology, Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Ningqiu Li
- Key Laboratory of Fishery Drug Development, Ministry of Agriculture and Rural Affairs, Guangdong Province Key Laboratory of Aquatic Animal Immune Technology, Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- *Correspondence: Ningqiu Li,
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9
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Cuellar-Santoyo AO, Ruiz-Rodríguez VM, Mares-Barbosa TB, Patrón-Soberano A, Howe AG, Portales-Pérez DP, Miquelajáuregui Graf A, Estrada-Sánchez AM. Revealing the contribution of astrocytes to glutamatergic neuronal transmission. Front Cell Neurosci 2023; 16:1037641. [PMID: 36744061 PMCID: PMC9893894 DOI: 10.3389/fncel.2022.1037641] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 12/20/2022] [Indexed: 01/20/2023] Open
Abstract
Research on glutamatergic neurotransmission has focused mainly on the function of presynaptic and postsynaptic neurons, leaving astrocytes with a secondary role only to ensure successful neurotransmission. However, recent evidence indicates that astrocytes contribute actively and even regulate neuronal transmission at different levels. This review establishes a framework by comparing glutamatergic components between neurons and astrocytes to examine how astrocytes modulate or otherwise influence neuronal transmission. We have included the most recent findings about the role of astrocytes in neurotransmission, allowing us to understand the complex network of neuron-astrocyte interactions. However, despite the knowledge of synaptic modulation by astrocytes, their contribution to specific physiological and pathological conditions remains to be elucidated. A full understanding of the astrocyte's role in neuronal processing could open fruitful new frontiers in the development of therapeutic applications.
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Affiliation(s)
- Ares Orlando Cuellar-Santoyo
- División de Biología Molecular, Laboratorio de Neurobiología, Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), San Luis Potosí, Mexico
| | - Victor Manuel Ruiz-Rodríguez
- División de Biología Molecular, Laboratorio de Neurobiología, Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), San Luis Potosí, Mexico
| | - Teresa Belem Mares-Barbosa
- División de Biología Molecular, Laboratorio de Neurobiología, Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), San Luis Potosí, Mexico,Translational and Molecular Medicine Laboratory, Research Center for Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí, Mexico
| | - Araceli Patrón-Soberano
- División de Biología Molecular, Laboratorio de Neurobiología, Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), San Luis Potosí, Mexico
| | - Andrew G. Howe
- Intelligent Systems Laboratory, HRL Laboratories, LLC, Malibu, CA, United States
| | - Diana Patricia Portales-Pérez
- Translational and Molecular Medicine Laboratory, Research Center for Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí, Mexico
| | | | - Ana María Estrada-Sánchez
- División de Biología Molecular, Laboratorio de Neurobiología, Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), San Luis Potosí, Mexico,*Correspondence: Ana María Estrada-Sánchez
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10
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The GABA and GABA-Receptor System in Inflammation, Anti-Tumor Immune Responses, and COVID-19. Biomedicines 2023; 11:biomedicines11020254. [PMID: 36830790 PMCID: PMC9953446 DOI: 10.3390/biomedicines11020254] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/16/2023] [Accepted: 01/16/2023] [Indexed: 01/20/2023] Open
Abstract
GABA and GABAA-receptors (GABAA-Rs) play major roles in neurodevelopment and neurotransmission in the central nervous system (CNS). There has been a growing appreciation that GABAA-Rs are also present on most immune cells. Studies in the fields of autoimmune disease, cancer, parasitology, and virology have observed that GABA-R ligands have anti-inflammatory actions on T cells and antigen-presenting cells (APCs), while also enhancing regulatory T cell (Treg) responses and shifting APCs toward anti-inflammatory phenotypes. These actions have enabled GABAA-R ligands to ameliorate autoimmune diseases, such as type 1 diabetes (T1D), multiple sclerosis (MS), and rheumatoid arthritis, as well as type 2 diabetes (T2D)-associated inflammation in preclinical models. Conversely, antagonism of GABAA-R activity promotes the pro-inflammatory responses of T cells and APCs, enhancing anti-tumor responses and reducing tumor burden in models of solid tumors. Lung epithelial cells also express GABA-Rs, whose activation helps maintain fluid homeostasis and promote recovery from injury. The ability of GABAA-R agonists to limit both excessive immune responses and lung epithelial cell injury may underlie recent findings that GABAA-R agonists reduce the severity of disease in mice infected with highly lethal coronaviruses (SARS-CoV-2 and MHV-1). These observations suggest that GABAA-R agonists may provide off-the-shelf therapies for COVID-19 caused by new SARS-CoV-2 variants, as well as novel beta-coronaviruses, which evade vaccine-induced immune responses and antiviral medications. We review these findings and further advance the notions that (1) immune cells possess GABAA-Rs to limit inflammation in the CNS, and (2) this natural "braking system" on inflammatory responses may be pharmacologically engaged to slow the progression of autoimmune diseases, reduce the severity of COVID-19, and perhaps limit neuroinflammation associated with long COVID.
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11
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Sleep and Neuroimmunomodulation for Maintenance of Optimum Brain Function: Role of Noradrenaline. Brain Sci 2022; 12:brainsci12121725. [PMID: 36552184 PMCID: PMC9776456 DOI: 10.3390/brainsci12121725] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/03/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Immune function and sleep are two normal physiological processes to protect the living organism from falling sick. There is hardly any disease in which they remain unaffected, though the quantum of effect may differ. Therefore, we propose the existence of a strong correlation between sleep (quality or quantity) and immune response. This may be supported by the fact that sleep loss modulates many of the immunological molecules, which includes interferons; however, not much is known about their mechanism of action. Sleep is divided into rapid eye movement sleep (REMS) and non-REMS. For practical reasons, experimental studies have been conducted mostly by inducing loss of REMS. It has been shown that withdrawal of noradrenaline (NA) is a necessity for generation of REMS. Moreover, NA level increases in the brain upon REMS loss and the elevated NA is responsible for many of the sleep loss-associated symptoms. In this review, we describe how sleep (and its disturbance/loss) modulates the immune system by modulating the NA level in the brain or vice versa to maintain immune functions, physiological homeostasis, and normal healthy living. The increased levels of NA during REMS loss may cause neuroinflammation possibly by glial activation (as NA is a key modulator of microglia). Therefore, maintaining sleep hygiene plays a crucial role for a normal healthy living.
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12
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Brunskine C, Passlick S, Henneberger C. Structural Heterogeneity of the GABAergic Tripartite Synapse. Cells 2022; 11:cells11193150. [PMID: 36231112 PMCID: PMC9563275 DOI: 10.3390/cells11193150] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 09/29/2022] [Accepted: 10/04/2022] [Indexed: 11/22/2022] Open
Abstract
The concept of the tripartite synapse describes the close interaction of pre- and postsynaptic elements and the surrounding astrocyte processes. For glutamatergic synapses, it is established that the presence of astrocytic processes and their structural arrangements varies considerably between and within brain regions and between synapses of the same neuron. In contrast, less is known about the organization of astrocytic processes at GABAergic synapses although bi-directional signaling is known to exist at these synapses too. Therefore, we established super-resolution expansion microscopy of GABAergic synapses and nearby astrocytic processes in the stratum radiatum of the mouse hippocampal CA1 region. By visualizing the presynaptic vesicular GABA transporter and the postsynaptic clustering protein gephyrin, we documented the subsynaptic heterogeneity of GABAergic synaptic contacts. We then compared the volume distribution of astrocytic processes near GABAergic synapses between individual synapses and with glutamatergic synapses. We made two novel observations. First, astrocytic processes were more abundant at the GABAergic synapses with large postsynaptic gephyrin clusters. Second, astrocytic processes were less abundant in the vicinity of GABAergic synapses compared to glutamatergic, suggesting that the latter may be selectively approached by astrocytes. Because of the GABA transporter distribution, we also speculate that this specific arrangement enables more efficient re-uptake of GABA into presynaptic terminals.
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Affiliation(s)
- Cindy Brunskine
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, 53127 Bonn, Germany
| | - Stefan Passlick
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, 53127 Bonn, Germany
| | - Christian Henneberger
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, 53127 Bonn, Germany
- German Center for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany
- Correspondence:
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13
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Clinical and Preclinical Studies of Fermented Foods and Their Effects on Alzheimer’s Disease. Antioxidants (Basel) 2022; 11:antiox11050883. [PMID: 35624749 PMCID: PMC9137914 DOI: 10.3390/antiox11050883] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 04/25/2022] [Accepted: 04/27/2022] [Indexed: 02/04/2023] Open
Abstract
The focus on managing Alzheimer’s disease (AD) is shifting towards prevention through lifestyle modification instead of treatments since the currently available treatment options are only capable of providing symptomatic relief marginally and result in various side effects. Numerous studies have reported that the intake of fermented foods resulted in the successful management of AD. Food fermentation is a biochemical process where the microorganisms metabolize the constituents of raw food materials, giving vastly different organoleptic properties and additional nutritional value, and improved biosafety effects in the final products. The consumption of fermented foods is associated with a wide array of nutraceutical benefits, including anti-oxidative, anti-inflammatory, neuroprotective, anti-apoptotic, anti-cancer, anti-fungal, anti-bacterial, immunomodulatory, and hypocholesterolemic properties. Due to their promising health benefits, fermented food products have a great prospect for commercialization in the food industry. This paper reviews the memory and cognitive enhancement and neuroprotective potential of fermented food products on AD, the recently commercialized fermented food products in the health and food industries, and their limitations. The literature reviewed here demonstrates a growing demand for fermented food products as alternative therapeutic options for the prevention and management of AD.
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14
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Sood A, Preeti K, Fernandes V, Khatri DK, Singh SB. Glia: A major player in glutamate-GABA dysregulation-mediated neurodegeneration. J Neurosci Res 2021; 99:3148-3189. [PMID: 34748682 DOI: 10.1002/jnr.24977] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/18/2021] [Accepted: 09/21/2021] [Indexed: 12/16/2022]
Abstract
The imbalance between glutamate and γ-aminobutyric acid (GABA) results in the loss of synaptic strength leading to neurodegeneration. The dogma on the field considered neurons as the main players in this excitation-inhibition (E/I) balance. However, current strategies focusing only on neurons have failed to completely understand this condition, bringing up the importance of glia as an alternative modulator for neuroinflammation as glia alter the activity of neurons and is a source of both neurotrophic and neurotoxic factors. This review's primary goal is to illustrate the role of glia over E/I balance in the central nervous system and its interaction with neurons. Rather than focusing only on the neuronal targets, we take a deeper look at glial receptors and proteins that could also be explored as drug targets, as they are early responders to neurotoxic insults. This review summarizes the neuron-glia interaction concerning GABA and glutamate, possible targets, and its involvement in the E/I imbalance in neurodegenerative diseases like Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis.
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Affiliation(s)
- Anika Sood
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Kumari Preeti
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Valencia Fernandes
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Dharmendra Kumar Khatri
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
| | - Shashi Bala Singh
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, India
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15
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Mirzaei N, Davis N, Chau TW, Sastre M. Astrocyte Reactivity in Alzheimer's Disease: Therapeutic Opportunities to Promote Repair. Curr Alzheimer Res 2021; 19:1-15. [PMID: 34719372 DOI: 10.2174/1567205018666211029164106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/02/2021] [Accepted: 07/31/2021] [Indexed: 11/22/2022]
Abstract
Astrocytes are fast climbing the ladder of importance in neurodegenerative disorders, particularly in Alzheimer's disease (AD), with the prominent presence of reactive astrocytes sur- rounding amyloid β- plaques, together with activated microglia. Reactive astrogliosis, implying morphological and molecular transformations in astrocytes, seems to precede neurodegeneration, suggesting a role in the development of the disease. Single-cell transcriptomics has recently demon- strated that astrocytes from AD brains are different from "normal" healthy astrocytes, showing dys- regulations in areas such as neurotransmitter recycling, including glutamate and GABA, and im- paired homeostatic functions. However, recent data suggest that the ablation of astrocytes in mouse models of amyloidosis results in an increase in amyloid pathology as well as in the inflammatory profile and reduced synaptic density, indicating that astrocytes mediate neuroprotective effects. The idea that interventions targeting astrocytes may have great potential for AD has therefore emerged, supported by a range of drugs and stem cell transplantation studies that have successfully shown a therapeutic effect in mouse models of AD. In this article, we review the latest reports on the role and profile of astrocytes in AD brains and how manipulation of astrocytes in animal mod- els has paved the way for the use of treatments enhancing astrocytic function as future therapeutic avenues for AD.
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Affiliation(s)
- Nazanin Mirzaei
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048. United States
| | - Nicola Davis
- Department of Brain Sciences, Imperial College London, Hammer-smith Hospital, Du Cane Road, LondonW12 0NN. United Kingdom
| | - Tsz Wing Chau
- Department of Brain Sciences, Imperial College London, Hammer-smith Hospital, Du Cane Road, LondonW12 0NN. United Kingdom
| | - Magdalena Sastre
- Department of Brain Sciences, Imperial College London, Hammer-smith Hospital, Du Cane Road, LondonW12 0NN. United Kingdom
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16
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Berezhnov AV, Fedotova EI, Sergeev AI, Teplov IY, Abramov AY. Dopamine controls neuronal spontaneous calcium oscillations via astrocytic signal. Cell Calcium 2021; 94:102359. [PMID: 33550209 DOI: 10.1016/j.ceca.2021.102359] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 01/14/2021] [Accepted: 01/16/2021] [Indexed: 01/10/2023]
Abstract
Dopamine is a neuromodulator and neurotransmitter responsible for a number of physiological processes. Dysfunctions of the dopamine metabolism and signalling are associated with neurological and psychiatric diseases. Here we report that in primary co-culture of neurons and astrocytes dopamine-induces calcium signal in astrocytes and suppress spontaneous synchronous calcium oscillations (SSCO) in neurons. Effect of dopamine on SSCO in neurons was dependent on calcium signal in astrocytes and could be modified by inhibition of dopamine-induced calcium signal or by stimulation of astrocytic calcium rise with ATP. Ability of dopamine to suppress SSCO in neurons was independent on D1- or D2- like receptors but dependent on GABA and alpha-adrenoreceptors. Inhibitor of monoaminoxidase bifemelane blocked effect of dopamine on astrocytes but also inhibited the effect dopamine on SSCO in neurons. These findings suggest that dopamine-induced calcium signal may stimulate release of neuromodulators such as GABA and adrenaline and thus suppress spontaneous calcium oscillations in neurons.
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Affiliation(s)
- Alexey V Berezhnov
- Institute of Cell Biophysics of the Russian Academy of Sciences, 142290, Pushchino, Russia; Cell Physiology and Pathology Laboratory, Orel State University, 302026, Orel, Russia.
| | - Evgeniya I Fedotova
- Institute of Cell Biophysics of the Russian Academy of Sciences, 142290, Pushchino, Russia; Cell Physiology and Pathology Laboratory, Orel State University, 302026, Orel, Russia
| | - Alexander I Sergeev
- Institute of Cell Biophysics of the Russian Academy of Sciences, 142290, Pushchino, Russia
| | - Ilya Y Teplov
- Institute of Cell Biophysics of the Russian Academy of Sciences, 142290, Pushchino, Russia
| | - Andrey Y Abramov
- Cell Physiology and Pathology Laboratory, Orel State University, 302026, Orel, Russia; Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, WC1N 3BG, London, UK.
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17
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Verkhratsky A, Augusto-Oliveira M, Pivoriūnas A, Popov A, Brazhe A, Semyanov A. Astroglial asthenia and loss of function, rather than reactivity, contribute to the ageing of the brain. Pflugers Arch 2020; 473:753-774. [PMID: 32979108 DOI: 10.1007/s00424-020-02465-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/05/2020] [Accepted: 09/09/2020] [Indexed: 12/13/2022]
Abstract
Astroglia represent a class of heterogeneous, in form and function, cells known as astrocytes, which provide for homoeostasis and defence of the central nervous system (CNS). Ageing is associated with morphological and functional remodelling of astrocytes with a prevalence of morphological atrophy and loss of function. In particular, ageing is associated with (i) decrease in astroglial synaptic coverage, (ii) deficits in glutamate and potassium clearance, (iii) reduced astroglial synthesis of synaptogenic factors such as cholesterol, (iv) decrease in aquaporin 4 channels in astroglial endfeet with subsequent decline in the glymphatic clearance, (v) decrease in astroglial metabolic support through the lactate shuttle, (vi) dwindling adult neurogenesis resulting from diminished proliferative capacity of radial stem astrocytes, (vii) decline in the astroglial-vascular coupling and deficient blood-brain barrier and (viii) decrease in astroglial ability to mount reactive astrogliosis. Decrease in reactive capabilities of astroglia are associated with rise of age-dependent neurodegenerative diseases. Astroglial morphology and function can be influenced and improved by lifestyle interventions such as intellectual engagement, social interactions, physical exercise, caloric restriction and healthy diet. These modifications of lifestyle are paramount for cognitive longevity.
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Affiliation(s)
- Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK. .,Achucarro Center for Neuroscience, IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain. .,Department of Neurosciences, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain.
| | - Marcus Augusto-Oliveira
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, 66075-110, Brazil
| | - Augustas Pivoriūnas
- Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, LT-01102, Vilnius, Lithuania
| | - Alexander Popov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya street 16/10, Moscow, Russia, 117997
| | - Alexey Brazhe
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya street 16/10, Moscow, Russia, 117997.,Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Alexey Semyanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya street 16/10, Moscow, Russia, 117997. .,Sechenov First Moscow State Medical University, Moscow, Russia.
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γ-Aminobutyric acid (GABA) from satellite glial cells tonically depresses the excitability of primary afferent fibers. Neurosci Res 2020; 170:50-58. [PMID: 32987088 DOI: 10.1016/j.neures.2020.08.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 08/10/2020] [Accepted: 08/26/2020] [Indexed: 01/08/2023]
Abstract
Primary afferent fibers express extrasynaptic GABAA and GABAB receptors in the axons and soma. However, whether these receptors are tonically activated by ambient GABA and the source of the neurotransmitter is presently unknown. Here, we show that GABA release from dorsal root ganglia (DRG) does not depend on extracellular calcium, but depends upon calcium released from intracellular stores, and is mediated by Best1 channels. Using a preparation consisting of the spinal nerve in continuity with the DRG and the dorsal root, we found that endogenous GABA tonically activates GABA receptors, depressing the excitability of the primary afferents. In addition, using HPLC we found that GABA is released in the DRG, and by immunofluorescence microscopy we show the presence of GABA, the Best1 channel, and some enzymes of the putrescine pathway of GABA biosynthesis, in glutamine synthase- and GFAP-positive satellite glial cells. Last, we found that the blockade of the Best1 channel activity reduced the excitability of primary afferents and prevented the activation of the GABA receptors. These results suggest that satellite glial cells may be the source of endogenous GABA released in the DRG via Best1 channels, which tonically activates extrasynaptic GABA receptors.
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19
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Kiljan S, Prins M, Baselmans BM, Bol JGJM, Schenk GJ, van Dam AM. Enhanced GABAergic Immunoreactivity in Hippocampal Neurons and Astroglia of Multiple Sclerosis Patients. J Neuropathol Exp Neurol 2020; 78:480-491. [PMID: 31100147 PMCID: PMC6524632 DOI: 10.1093/jnen/nlz028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Cognitive dysfunction occurs frequently in multiple sclerosis (MS). Research suggests that hippocampal lesions and GABAergic neurotransmitter changes contribute to cognitive dysfunction. In the present study, we aim to determine the cellular changes in GABAergic expression in MS hippocampus related to inflammation and demyelination. To this end, the presence and inflammatory activity of demyelinating lesions was determined by immunohistochemistry in human postmortem hippocampal tissue of 15 MS patients and 9 control subjects. Subsequently, GABAergic cells were visualized using parvalbumin (PV) and glutamate acid decarboxylase 67 (GAD67) markers. Fluorescent colabeling was performed of GAD67 with neuronal nuclei, PV, astrocytic glial fibrillary acidic protein, or vesicular GABA transporter. We observed increased GAD67-positive (GAD67+) neuron and synapse numbers in the CA1 of MS patients with active hippocampal lesions, not due to neurogenesis. The number and size of PV-positive neurons remained unchanged. GAD67+ astrocytes were more numerous in hippocampal white matter than grey matter lesions. Additionally, in MS patients with active hippocampal lesions GAD67+ astrocyte surface area was increased. Disturbed cognition was most prevalent in MS patients with active hippocampal lesions. Summarizing, increased GAD67 immunoreactivity occurs in neurons and astrocytes and relates to hippocampal inflammation and possibly disturbed cognition in MS.
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Affiliation(s)
- Svenja Kiljan
- Department of Anatomy and Neurosciences, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Marloes Prins
- Department of Anatomy and Neurosciences, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Bart M Baselmans
- Department of Anatomy and Neurosciences, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.,Bart M. Baselmans, Department of Biological Psychology, VU University, Amsterdam, The Netherlands
| | - John G J M Bol
- Department of Anatomy and Neurosciences, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Geert J Schenk
- Department of Anatomy and Neurosciences, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Anne-Marie van Dam
- Department of Anatomy and Neurosciences, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
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Gaidin SG, Zinchenko VP, Sergeev AI, Teplov IY, Mal'tseva VN, Kosenkov AM. Activation of alpha‐2 adrenergic receptors stimulates GABA release by astrocytes. Glia 2020; 68:1114-1130. [DOI: 10.1002/glia.23763] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 11/26/2019] [Accepted: 12/03/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Sergei G. Gaidin
- Institute of Cell Biophysics of the Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences” Pushchino Russia
| | - Valery P. Zinchenko
- Institute of Cell Biophysics of the Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences” Pushchino Russia
| | - Alexander I. Sergeev
- Institute of Cell Biophysics of the Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences” Pushchino Russia
| | - Ilia Y. Teplov
- Institute of Cell Biophysics of the Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences” Pushchino Russia
| | - Valentina N. Mal'tseva
- Institute of Cell Biophysics of the Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences” Pushchino Russia
| | - Artem M. Kosenkov
- Institute of Cell Biophysics of the Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences” Pushchino Russia
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21
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Portal B, Delcourte S, Rovera R, Lejards C, Bullich S, Malnou CE, Haddjeri N, Déglon N, Guiard BP. Genetic and pharmacological inactivation of astroglial connexin 43 differentially influences the acute response of antidepressant and anxiolytic drugs. Acta Physiol (Oxf) 2020; 229:e13440. [PMID: 31925934 DOI: 10.1111/apha.13440] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/18/2019] [Accepted: 01/02/2020] [Indexed: 12/12/2022]
Abstract
AIM Astroglial connexins (Cxs) 30 and 43 are engaged in gap junction and hemichannel activities. Evidence suggests that these functional entities contribute to regulating neurotransmission, thereby influencing brain functions. In particular, preclinical and clinical findings highlight a role of Cx43 in animal models of depression. However, the role of these proteins in response to currently available psychotropic drugs is still unknown. METHODS To investigate this, we evaluated the behavioural effects of the genetic and pharmacological inactivation of Cx43 on the antidepressant- and anxiolytic-like activities of the selective serotonin reuptake inhibitor fluoxetine and the benzodiazepine diazepam, respectively. RESULTS A single administration of fluoxetine (18 mg/kg; i.p.) produced a higher increase in hippocampal extracellular serotonin levels, and a greater antidepressant-like effect in the tail suspension test in Cx43 knock-down (KD) mice bred on a C57BL/6 background compared to their wild-type littermates. Similarly, in outbred Swiss wild-type mice, the intra-hippocampal injection of a shRNA-Cx43 or the acute systemic injection of the Cxs inhibitor carbenoxolone (CBX: 10 mg/kg; i.p.) potentiated the antidepressant-like effects of fluoxetine. Evaluating the effects of such strategies on diazepam (0.5 mg/kg; i.p.), the results indicate that Cx43 KD mice or wild-types injected with a shRNA-Cx43 in the amygdala, but not in the hippocampus, attenuated the anxiolytic-like effects of this benzodiazepine in the elevated plus maze. The chronic systemic administration of CBX mimicked the latter observations. CONCLUSION Collectively, these data pave the way to the development of potentiating strategies in the field of psychiatry based on the modulation of astroglial Cx43.
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Affiliation(s)
- Benjamin Portal
- Centre de Recherches sur la Cognition Animale (CRCA) Centre de Biologie Intégrative (CBI) Université Paul Sabatier Toulouse III Toulouse France
| | - Sarah Delcourte
- Univ Lyon Université Claude Bernard Lyon 1 Inserm Stem Cell and Brain Research Institute U1208 Bron France
| | - Renaud Rovera
- Univ Lyon Université Claude Bernard Lyon 1 Inserm Stem Cell and Brain Research Institute U1208 Bron France
| | - Camille Lejards
- Centre de Recherches sur la Cognition Animale (CRCA) Centre de Biologie Intégrative (CBI) Université Paul Sabatier Toulouse III Toulouse France
| | - Sebastien Bullich
- Centre de Recherches sur la Cognition Animale (CRCA) Centre de Biologie Intégrative (CBI) Université Paul Sabatier Toulouse III Toulouse France
| | - Cécile E. Malnou
- Centre de Physiopathologie Toulouse‐Purpan (CPTP) INSERM CNRS Université de Toulouse Toulouse France
| | - Nasser Haddjeri
- Univ Lyon Université Claude Bernard Lyon 1 Inserm Stem Cell and Brain Research Institute U1208 Bron France
| | - Nicole Déglon
- Department of Clinical Neurosciences Laboratory of Neurotherapies and Neuromodulation (LNTM) Lausanne University Hospital Lausanne Switzerland
- Neuroscience Research Center LNTM Lausanne University Hospital Lausanne Switzerland
| | - Bruno P. Guiard
- Centre de Recherches sur la Cognition Animale (CRCA) Centre de Biologie Intégrative (CBI) Université Paul Sabatier Toulouse III Toulouse France
- Faculté de Pharmacie Université Paris Sud Université Paris‐Saclay Chatenay‐Malabry France
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Łątka K, Jończyk J, Bajda M. γ-Aminobutyric acid transporters as relevant biological target: Their function, structure, inhibitors and role in the therapy of different diseases. Int J Biol Macromol 2020; 158:S0141-8130(20)32987-1. [PMID: 32360967 DOI: 10.1016/j.ijbiomac.2020.04.126] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 04/17/2020] [Accepted: 04/18/2020] [Indexed: 12/13/2022]
Abstract
γ-Aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the nervous system. It plays a crucial role in many physiological processes. Upon release from the presynaptic element, it is removed from the synaptic cleft by reuptake due to the action of GABA transporters (GATs). GATs belong to a large SLC6 protein family whose characteristic feature is sodium-dependent relocation of neurotransmitters through the cell membrane. GABA transporters are characterized in many contexts, but their spatial structure is not fully known. They are divided into four types, which differ in occurrence and role. Herein, the special attention was paid to these transporting proteins. This comprehensive review presents the current knowledge about GABA transporters. Their distribution in the body, physiological functions and possible utilization in the therapy of different diseases were fully discussed. The important structural features were described based on published data, including sequence analysis, mutagenesis studies, and comparison with known SLC6 transporters for leucine (LeuT), dopamine (DAT) and serotonin (SERT). Moreover, the most important inhibitors of GABA transporters of various basic scaffolds, diverse selectivity and potency were presented.
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Affiliation(s)
- Kamil Łątka
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Physicochemical Drug Analysis, 30-688 Cracow, Medyczna 9, Poland
| | - Jakub Jończyk
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Physicochemical Drug Analysis, 30-688 Cracow, Medyczna 9, Poland
| | - Marek Bajda
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Physicochemical Drug Analysis, 30-688 Cracow, Medyczna 9, Poland.
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Burman RJ, Raimondo JV, Jefferys JG, Sen A, Akerman CJ. The transition to status epilepticus: how the brain meets the demands of perpetual seizure activity. Seizure 2020; 75:137-144. [DOI: 10.1016/j.seizure.2019.09.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 09/23/2019] [Indexed: 02/08/2023] Open
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Katsouri L, Birch AM, Renziehausen AWJ, Zach C, Aman Y, Steeds H, Bonsu A, Palmer EOC, Mirzaei N, Ries M, Sastre M. Ablation of reactive astrocytes exacerbates disease pathology in a model of Alzheimer's disease. Glia 2019; 68:1017-1030. [PMID: 31799735 PMCID: PMC7383629 DOI: 10.1002/glia.23759] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 11/20/2019] [Accepted: 11/21/2019] [Indexed: 02/06/2023]
Abstract
The role of astrocytes in the progression of Alzheimer's disease (AD) remains poorly understood. We assessed the consequences of ablating astrocytic proliferation in 9 months old double transgenic APP23/GFAP-TK mice. Treatment of these mice with the antiviral agent ganciclovir conditionally ablates proliferating reactive astrocytes. The loss of proliferating astrocytes resulted in significantly increased levels of monomeric amyloid-β (Aβ) in brain homogenates, associated with reduced enzymatic degradation and clearance mechanisms. In addition, our data revealed exacerbated memory deficits in mice lacking proliferating astrocytes concomitant with decreased levels of synaptic markers and higher expression of pro-inflammatory cytokines. Our data suggest that loss of reactive astrocytes in AD aggravates amyloid pathology and memory loss, possibly via disruption of amyloid clearance and enhanced neuroinflammation.
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Affiliation(s)
- Loukia Katsouri
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Amy M Birch
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | | | - Carolin Zach
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Yahyah Aman
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Hannah Steeds
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Angela Bonsu
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Emily O C Palmer
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Nazanin Mirzaei
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Miriam Ries
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Magdalena Sastre
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
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25
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Hwang JH, Wu SJ, Wu PL, Shih YY, Chan YC. Neuroprotective effect of tempeh against lipopolysaccharide-induced damage in BV-2 microglial cells. Nutr Neurosci 2019; 22:840-849. [PMID: 29595091 DOI: 10.1080/1028415x.2018.1456040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Objectives: This study evaluated the bioactive composition of tempeh products and examined the effects of tempeh on BV-2 microglial cell cytotoxicity, neurotrophic effects, and expression of inflammatory genes.Methods: Tempeh products included soybean fermented by Rhizopus, soybean fermented through cocultivation with Rhizopus and Lactobacillus, and red bean fermented through cocultivation with Rhizopus and Lactobacillus (RT-C). We analyzed the bioactive contents of tempeh extracts and evaluated the effects of tempeh water extract on lipopolysaccharide (LPS)-treated BV-2 cells.Results: The results showed that RT-C water extract had the highest concentrations of γ-aminobutyric acid (GABA) and anthocyanin. The tempeh water extracts, especially RT-C, reduced the formation of LPS-induced reactive oxygen species, downregulated the levels of nitric oxide synthase and phospho-cyclic-AMP response element-binding protein, and upregulated the expression of brain-derived neurotrophic factor (BDNF).Discussion: Our data demonstrate that RT-C has the highest concentrations of GABA and anthocyanin, more effectively reduces oxidative stress and inflammation, and increases the expression of BDNF in LPS-induced BV-2 cells.
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Affiliation(s)
- Juen-Haur Hwang
- Department of Otolaryngology, Dalin Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Chiayi, Taiwan
- School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Shu-Jing Wu
- Department of Nutritional Health, Chia-Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Po-Long Wu
- Biotech Business Center, Refining and Manufacturing Research Institute, CPC Corporation, Chiayi, Taiwan
| | - Yong-Yao Shih
- Department of Food and Nutrition, Providence University, Taichung, Taiwan
| | - Yin-Ching Chan
- Department of Food and Nutrition, Providence University, Taichung, Taiwan
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26
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Dal Prà I, Armato U, Chiarini A. Family C G-Protein-Coupled Receptors in Alzheimer's Disease and Therapeutic Implications. Front Pharmacol 2019; 10:1282. [PMID: 31719824 PMCID: PMC6826475 DOI: 10.3389/fphar.2019.01282] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 10/07/2019] [Indexed: 12/12/2022] Open
Abstract
Alzheimer’s disease (AD), particularly its sporadic or late-onset form (SAD/LOAD), is the most prevalent (96–98% of cases) neurodegenerative dementia in aged people. AD’s neuropathology hallmarks are intrabrain accumulation of amyloid-β peptides (Aβs) and of hyperphosphorylated Tau (p-Tau) proteins, diffuse neuroinflammation, and progressive death of neurons and oligodendrocytes. Mounting evidences suggest that family C G-protein-coupled receptors (GPCRs), which include γ-aminobutyric acid B receptors (GABABRs), metabotropic glutamate receptors (mGluR1-8), and the calcium-sensing receptor (CaSR), are involved in many neurotransmitter systems that dysfunction in AD. This review updates the available knowledge about the roles of GPCRs, particularly but not exclusively those expressed by brain astrocytes, in SAD/LOAD onset and progression, taking stock of their respective mechanisms of action and of their potential as anti-AD therapeutic targets. In particular, GABABRs prevent Aβs synthesis and neuronal hyperexcitability and group I mGluRs play important pathogenetic roles in transgenic AD-model animals. Moreover, the specific binding of Aβs to the CaSRs of human cortical astrocytes and neurons cultured in vitro engenders a pathological signaling that crucially promotes the surplus synthesis and release of Aβs and hyperphosphorylated Tau proteins, and also of nitric oxide, vascular endothelial growth factor-A, and proinflammatory agents. Concurrently, Aβs•CaSR signaling hinders the release of soluble (s)APP-α peptide, a neurotrophic agent and GABABR1a agonist. Altogether these effects progressively kill human cortical neurons in vitro and likely also in vivo. Several CaSR’s negative allosteric modulators suppress all the noxious effects elicited by Aβs•CaSR signaling in human cortical astrocytes and neurons thus safeguarding neurons’ viability in vitro and raising hopes about their potential therapeutic benefits in AD patients. Further basic and clinical investigations on these hot topics are needed taking always heed that activation of the several brain family C GPCRs may elicit divergent upshots according to the models studied.
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Affiliation(s)
- Ilaria Dal Prà
- Human Histology and Embryology Unit, University of Verona Medical School, Verona, Italy
| | - Ubaldo Armato
- Human Histology and Embryology Unit, University of Verona Medical School, Verona, Italy
| | - Anna Chiarini
- Human Histology and Embryology Unit, University of Verona Medical School, Verona, Italy
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27
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Hawrysh PJ, Buck LT. Oxygen-sensitive interneurons exhibit increased activity and GABA release during ROS scavenging in the cerebral cortex of the western painted turtle. J Neurophysiol 2019; 122:466-479. [PMID: 31141433 DOI: 10.1152/jn.00104.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The western painted turtle (Chrysemys picta bellii) has the unique ability of surviving several months in the absence of oxygen, which is termed anoxia. One major protective strategy that the turtle employs during anoxia is a reduction in neuronal electrical activity, which may result from a natural reduction in reactive oxygen species (ROS). We previously linked a reduction in ROS levels to an increase in γ-amino butyric acid (GABA) receptor currents. The purpose of this study is to understand how fast-spiking, GABA-releasing neurons respond to reductions in ROS and how this affects GABA release. Using a fluorescence-coupled enzymatic microplate assay for GABA, we found that anoxia, the ROS scavenger N-(2-mercaptopriopionyl)glycine (MPG), or the mitochondria-specific ROS scavenger MitoTEMPO resulted in a 2.5-, 2.0-, and 2.5-fold increase in extracellular GABA concentration, respectively. This phenomenon could be blocked with TTX, indicating that it is activity dependent. Using whole cell patch-clamping techniques, we found that fast-spiking, burst-firing GABAergic turtle neurons increase the duration and number of action potentials per burst by 26% and 42%, respectively, in response to ROS scavenging via MPG. These results suggest that the reduction in mitochondrially produced ROS that occurs during anoxia leads to increased GABA release, which promotes postsynaptic inhibitory activity through activation of GABA receptors.NEW & NOTEWORTHY This is a novel study examining the response of cerebral cortical stellate interneurons to anoxia and mitochondrial reactive oxygen species (ROS) scavenging with MitoTEMPO. Under both conditions burst firing increases in these cells, and we show that extracellular GABA release increases in the presence of the ROS scavenger. We conclude that in the anoxia-tolerant painted turtle brain, a decrease in ROS levels is an important low oxygen signal.
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Affiliation(s)
- Peter John Hawrysh
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Leslie Thomas Buck
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada.,Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
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Fouyssac M, Belin D. Beyond drug-induced alteration of glutamate homeostasis, astrocytes may contribute to dopamine-dependent intrastriatal functional shifts that underlie the development of drug addiction: A working hypothesis. Eur J Neurosci 2019; 50:3014-3027. [PMID: 30968489 PMCID: PMC6852203 DOI: 10.1111/ejn.14416] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/18/2019] [Accepted: 03/26/2019] [Indexed: 12/30/2022]
Abstract
The transition from recreational drug use to compulsive drug‐seeking habits, the hallmark of addiction, has been shown to depend on a shift in the locus of control over behaviour from the ventral to the dorsolateral striatum. This process has hitherto been considered to depend on the aberrant engagement of dopamine‐dependent plasticity processes within neuronal networks. However, exposure to drugs of abuse also triggers cellular and molecular adaptations in astrocytes within the striatum which could potentially contribute to the intrastriatal transitions observed during the development of drug addiction. Pharmacological interventions aiming to restore the astrocytic mechanisms responsible for maintaining homeostatic glutamate concentrations in the nucleus accumbens, that are altered by chronic exposure to addictive drugs, abolish the propensity to relapse in both preclinical and, to a lesser extent, clinical studies. Exposure to drugs of abuse also alters the function of astrocytes in the dorsolateral striatum, wherein dopaminergic mechanisms control drug‐seeking habits, associated compulsivity and relapse. This suggests that drug‐induced alterations in the glutamatergic homeostasis maintained by astrocytes throughout the entire striatum may interact with dopaminergic mechanisms to promote aberrant plasticity processes that contribute to the maintenance of maladaptive drug‐seeking habits. Capitalising on growing evidence that astrocytes play a fundamental regulatory role in glutamate and dopamine transmission in the striatum, we present an innovative model of a quadripartite synaptic microenvironment within which astrocytes channel functional interactions between the dopaminergic and glutamatergic systems that may represent the primary striatal functional unit that undergoes drug‐induced adaptations eventually leading to addiction.
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Affiliation(s)
- Maxime Fouyssac
- Department of Psychology, University of Cambridge, Cambridge, UK
| | - David Belin
- Department of Psychology, University of Cambridge, Cambridge, UK
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29
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Zamberlam CR, Tilger MAS, Moraes L, Cerutti JM, Cerutti SM. Ginkgo biloba treatments reverse the impairment of conditioned suppression acquisition induced by GluN2B-NMDA and 5-HT 1A receptor blockade: Modulatory effects of the circuitry of the dorsal hippocampal formation. Physiol Behav 2019; 209:112534. [PMID: 31071338 DOI: 10.1016/j.physbeh.2019.04.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/29/2019] [Accepted: 04/26/2019] [Indexed: 01/09/2023]
Abstract
To improve our understanding of the effects of standardized extract of Ginkgo biloba (EGb) as a cognitive enhancer, we investigated the conditioned lick suppression-induced expression (mRNA and protein) of the GluN2B-containing N-methyl-D-aspartic acid receptor (GluN2B-NMDAR), serotonin (5-HT) 1A receptor (5-HT1AR), gamma-aminobutyric acid type A receptor (GABAAR) and glial fibrillary acidic protein (GFAP) in the dorsal hippocampal formation (dHF) of untreated and EGb-treated (0.25, 0.5 and 1.0 g.kg-1) groups of rats. To substantiate our data, we analysed the molecular changes in dHF following treatment with vehicle, with agonists or antagonists of GABAAR, GluN2B-NMDAR and 5-HT1AR or with one of these antagonists prior to EGb and fear memory acquisition. Additionally, we performed a pharmacological analysis of the drug-receptor-receptor interactions and their supplemental role in fear memory by blocking individual receptors and analysed the possible changes in expression level with each of the other receptors in the study as well as astrocytes. Our data show for the first time that EGb treatment not only upregulated GluN2B, GABAAR-α5, and GFAP compared with the control but also differentially upregulated GABAAR-α1 in the dHF and 5HT1AR in the CA3. We found that the activation of GABAARs (diazepam) and the inactivation of GluN2B-NMDARs (Ro25-6981) or 5-HT1AR ((S)-WAY100135) resulted in memory impairment. Further, higher doses of EGb treatment reversed the effect of blocking GluN2B (P < 0.001) and 5-HT1AR (P < 0.001). Here, treatment with Ro25-6981 + EGb or (S)-WAY100135 + EGb prevented the impairment of the acquisition of lick suppression in association with the upregulation or prevention of the downregulation of Grin2b expression as well as the expression of GluN2B-NMDA and/or α1 and α5 subunit-containing GABAAR in the CA1 (P < 0.0001). Our data are in line with previous findings concerning the necessity of GluN2B for fear memory formation and add to the current knowledge of the role of the GABAAR-α1 and -α5 subunits and of GluN2B as a target of cognitive enhancers. Furthermore, our data show that these receptors play a complementary role in controlling the neural circuitry in the dHF that seems to be essential to conditioned lick suppression and the modulatory effects of EGb.
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Affiliation(s)
- Cláudia R Zamberlam
- Universidade Federal de São Paulo. Departamento de Ciências Biológicas. Laboratório de Farmacologia Celular e Comportamental, Diadema, SP, Brazil; Universidade Federal de São Paulo, Departamento de Morfologia e Genética, Laboratório Bases Genéticas do Tumor da Tiróide, São Paulo, SP, Brazil
| | - Myrcea A S Tilger
- Universidade Federal de São Paulo. Departamento de Ciências Biológicas. Laboratório de Farmacologia Celular e Comportamental, Diadema, SP, Brazil
| | - Laís Moraes
- Universidade Federal de São Paulo, Departamento de Morfologia e Genética, Laboratório Bases Genéticas do Tumor da Tiróide, São Paulo, SP, Brazil
| | - Janete M Cerutti
- Universidade Federal de São Paulo, Departamento de Morfologia e Genética, Laboratório Bases Genéticas do Tumor da Tiróide, São Paulo, SP, Brazil
| | - Suzete M Cerutti
- Universidade Federal de São Paulo. Departamento de Ciências Biológicas. Laboratório de Farmacologia Celular e Comportamental, Diadema, SP, Brazil.
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30
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Mahmoud S, Gharagozloo M, Simard C, Gris D. Astrocytes Maintain Glutamate Homeostasis in the CNS by Controlling the Balance between Glutamate Uptake and Release. Cells 2019; 8:cells8020184. [PMID: 30791579 PMCID: PMC6406900 DOI: 10.3390/cells8020184] [Citation(s) in RCA: 322] [Impact Index Per Article: 64.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 02/15/2019] [Accepted: 02/19/2019] [Indexed: 01/26/2023] Open
Abstract
Glutamate is one of the most prevalent neurotransmitters released by excitatory neurons in the central nervous system (CNS); however, residual glutamate in the extracellular space is, potentially, neurotoxic. It is now well-established that one of the fundamental functions of astrocytes is to uptake most of the synaptically-released glutamate, which optimizes neuronal functions and prevents glutamate excitotoxicity. In the CNS, glutamate clearance is mediated by glutamate uptake transporters expressed, principally, by astrocytes. Interestingly, recent studies demonstrate that extracellular glutamate stimulates Ca2+ release from the astrocytes’ intracellular stores, which triggers glutamate release from astrocytes to the adjacent neurons, mostly by an exocytotic mechanism. This released glutamate is believed to coordinate neuronal firing and mediate their excitatory or inhibitory activity. Therefore, astrocytes contribute to glutamate homeostasis in the CNS, by maintaining the balance between their opposing functions of glutamate uptake and release. This dual function of astrocytes represents a potential therapeutic target for CNS diseases associated with glutamate excitotoxicity. In this regard, we summarize the molecular mechanisms of glutamate uptake and release, their regulation, and the significance of both processes in the CNS. Also, we review the main features of glutamate metabolism and glutamate excitotoxicity and its implication in CNS diseases.
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Affiliation(s)
- Shaimaa Mahmoud
- Program of Immunology, Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
| | - Marjan Gharagozloo
- Program of Immunology, Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
| | - Camille Simard
- Program of Immunology, Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
| | - Denis Gris
- Program of Immunology, Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
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Christensen RK, Delgado-Lezama R, Russo RE, Lind BL, Alcocer EL, Rath MF, Fabbiani G, Schmitt N, Lauritzen M, Petersen AV, Carlsen EM, Perrier JF. Spinal dorsal horn astrocytes release GABA in response to synaptic activation. J Physiol 2018; 596:4983-4994. [PMID: 30079574 DOI: 10.1113/jp276562] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 08/01/2018] [Indexed: 02/02/2023] Open
Abstract
KEY POINTS GABA is an essential molecule for sensory information processing. It is usually assumed to be released by neurons. Here we show that in the dorsal horn of the spinal cord, astrocytes respond to glutamate by releasing GABA. Our findings suggest a novel role for astrocytes in somatosensory information processing. ABSTRACT Astrocytes participate in neuronal signalling by releasing gliotransmitters in response to neurotransmitters. We investigated if astrocytes from the dorsal horn of the spinal cord of adult red-eared turtles (Trachemys scripta elegans) release GABA in response to glutamatergic receptor activation. For this, we developed a GABA sensor consisting of HEK cells expressing GABAA receptors. By positioning the sensor recorded in the whole-cell patch-clamp configuration within the dorsal horn of a spinal cord slice, we could detect GABA in the extracellular space. Puff application of glutamate induced GABA release events with time courses that exceeded the duration of inhibitory postsynaptic currents by one order of magnitude. Because the events were neither affected by extracellular addition of nickel, cadmium and tetrodotoxin nor by removal of Ca2+ , we concluded that they originated from non-neuronal cells. Immunohistochemical staining allowed the detection of GABA in a fraction of dorsal horn astrocytes. The selective stimulation of A∂ and C fibres in a dorsal root filament induced a Ca2+ increase in astrocytes loaded with Oregon Green BAPTA. Finally, chelating Ca2+ in a single astrocyte was sufficient to prevent the GABA release evoked by glutamate. Our results indicate that glutamate triggers the release of GABA from dorsal horn astrocytes with a time course compatible with the integration of sensory inputs.
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Affiliation(s)
- Rasmus Kordt Christensen
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Rodolfo Delgado-Lezama
- Departamento de Fisiología, Biofísica y Neurociencias Cinvestav-IPN Avenida IPN 2508, Col. Zacatenco México City, CP, 07300, Mexico
| | - Raúl E Russo
- Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, 11600, Montevideo, Uruguay
| | - Barbara Lykke Lind
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Emanuel Loeza Alcocer
- Departamento de Fisiología, Biofísica y Neurociencias Cinvestav-IPN Avenida IPN 2508, Col. Zacatenco México City, CP, 07300, Mexico
| | - Martin Fredensborg Rath
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Gabriela Fabbiani
- Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, 11600, Montevideo, Uruguay
| | - Nicole Schmitt
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Martin Lauritzen
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Anders Victor Petersen
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Eva Meier Carlsen
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Jean-François Perrier
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
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Peripheral GABA A receptor-mediated signaling facilitates persistent inflammatory hypersensitivity. Neuropharmacology 2018; 135:572-580. [PMID: 29634983 DOI: 10.1016/j.neuropharm.2018.04.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 03/30/2018] [Accepted: 04/06/2018] [Indexed: 01/26/2023]
Abstract
Unlike in the central nervous system (CNS), in the adult peripheral nervous system (PNS), activation of GABAA receptors (GABAAR) is excitatory because of the relatively high concentration of intracellular chloride in these neurons. Indeed, exogenous GABA and muscimol, a GABAAR agonist, exacerbate acute inflammatory hypersensitivity in rodents. However, it remains unclear whether peripheral GABAAR and the endogenous GABA play an important role in persistent inflammatory hypersensitivity. In this study, we thus investigated how peripheral GABAAR affects pain hypersensitivity by using the complete Freund's adjuvant (CFA)-induced persistent inflammatory pain mouse model. We found that intraplantar (i.pl.) administration of GABAAR antagonists, picrotoxin, and 1(S),9(R)-(-)-bicuculline methiodide significantly inhibited both spontaneous nociceptive (paw licking and flinching) behavior and mechanical hypersensitivity in CFA-injected mice at day 3 (D3), but not in naïve mice. Interestingly, CFA-induced mechanical hypersensitivity was significantly reversed by anti-GABA antibody (anti-GABA, i.pl.). In addition, RT-qPCR revealed that glutamate decarboxylase Gad1 (GAD 67) and Gad2 (GAD 65) mRNA expression was also upregulated in the ipsilateral hind paw of CFA-injected mice at D3. Finally, 5α-pregnan-3α-ol-20-one (3α,5α-THP), a selective positive allosteric modulator of GABAAR, produced mechanical hypersensitivity in naïve mice in a dose-dependent manner. Taken together, our results indicate that peripheral GABAAR and endogenous GABA, possibly produced by the inflamed tissue, potentiate CFA-induced persistent inflammatory hypersensitivity, suggesting that they can be used as a therapeutic target for alleviating inflammatory pain.
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Rakela B, Brehm P, Mandel G. Astrocytic modulation of excitatory synaptic signaling in a mouse model of Rett syndrome. eLife 2018; 7:31629. [PMID: 29313799 PMCID: PMC5771668 DOI: 10.7554/elife.31629] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 01/08/2018] [Indexed: 12/16/2022] Open
Abstract
Studies linking mutations in Methyl CpG Binding Protein 2 (MeCP2) to physiological defects in the neurological disease, Rett syndrome, have focused largely upon neuronal dysfunction despite MeCP2 ubiquitous expression. Here we explore roles for astrocytes in neuronal network function using cortical slice recordings. We find that astrocyte stimulation in wild-type mice increases excitatory synaptic activity that is absent in male mice lacking MeCP2 globally. To determine the cellular basis of the defect, we exploit a female mouse model for Rett syndrome that expresses wild-type MeCP2-GFP in a mosaic distribution throughout the brain, allowing us to test all combinations of wild-type and mutant cells. We find that the defect is dependent upon MeCP2 expression status in the astrocytes and not in the neurons. Our findings highlight a new role for astrocytes in regulation of excitatory synaptic signaling and in the neurological defects associated with Rett syndrome.
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Affiliation(s)
- Benjamin Rakela
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Paul Brehm
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Gail Mandel
- Vollum Institute, Oregon Health & Science University, Portland, United States
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34
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Lin YH, Liang HY, Xu K, Ni HY, Dong J, Xiao H, Chang L, Wu HY, Li F, Zhu DY, Luo CX. Dissociation of nNOS from PSD-95 promotes functional recovery after cerebral ischaemia in mice through reducing excessive tonic GABA release from reactive astrocytes. J Pathol 2017; 244:176-188. [DOI: 10.1002/path.4999] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 09/12/2017] [Accepted: 10/12/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Yu-Hui Lin
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
| | - Hai-Ying Liang
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
| | - Ke Xu
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
| | - Huan-Yu Ni
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
| | - Jian Dong
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
| | - Hui Xiao
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
| | - Lei Chang
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
- Laboratory of Cerebrovascular Disease; Nanjing Medical University; Nanjing PR China
| | - Hai-Yin Wu
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
- Laboratory of Cerebrovascular Disease; Nanjing Medical University; Nanjing PR China
| | - Fei Li
- Department of Medicinal Chemistry, School of Pharmacy; Nanjing Medical University; Nanjing PR China
| | - Dong-Ya Zhu
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
- Laboratory of Cerebrovascular Disease; Nanjing Medical University; Nanjing PR China
| | - Chun-Xia Luo
- Department of Pharmacology, School of Pharmacy; Nanjing Medical University; Nanjing PR China
- Laboratory of Cerebrovascular Disease; Nanjing Medical University; Nanjing PR China
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35
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Fried DE, Watson RE, Robson SC, Gulbransen BD. Ammonia modifies enteric neuromuscular transmission through glial γ-aminobutyric acid signaling. Am J Physiol Gastrointest Liver Physiol 2017; 313:G570-G580. [PMID: 28838986 PMCID: PMC5814673 DOI: 10.1152/ajpgi.00154.2017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 08/17/2017] [Accepted: 08/17/2017] [Indexed: 01/31/2023]
Abstract
Impaired gut motility may contribute, at least in part, to the development of systemic hyperammonemia and systemic neurological disorders in inherited metabolic disorders, or in severe liver and renal disease. It is not known whether enteric neurotransmission regulates intestinal luminal and hence systemic ammonia levels by induced changes in motility. Here, we propose and test the hypothesis that ammonia acts through specific enteric circuits to influence gut motility. We tested our hypothesis by recording the effects of ammonia on neuromuscular transmission in tissue samples from mice, pigs, and humans and investigated specific mechanisms using novel mutant mice, selective drugs, cellular imaging, and enzyme-linked immunosorbent assays. Exogenous ammonia increased neurogenic contractions and decreased neurogenic relaxations in segments of mouse, pig, and human intestine. Enteric glial cells responded to ammonia with intracellular Ca2+ responses. Inhibition of glutamine synthetase and the deletion of glial connexin-43 channels in hGFAP::CreERT2+/-/connexin43f/f mice potentiated the effects of ammonia on neuromuscular transmission. The effects of ammonia on neuromuscular transmission were blocked by GABAA receptor antagonists, and ammonia drove substantive GABA release as did the selective pharmacological activation of enteric glia in GFAP::hM3Dq transgenic mice. We propose a novel mechanism whereby local ammonia is operational through GABAergic glial signaling to influence enteric neuromuscular circuits that regulate intestinal motility. Therapeutic manipulation of these mechanisms may benefit a number of neurological, hepatic, and renal disorders manifesting hyperammonemia.NEW & NOTEWORTHY We propose that local circuits in the enteric nervous system sense and regulate intestinal ammonia. We show that ammonia modifies enteric neuromuscular transmission to increase motility in human, pig, and mouse intestine model systems. The mechanisms underlying the effects of ammonia on enteric neurotransmission include GABAergic pathways that are regulated by enteric glial cells. Our new data suggest that myenteric glial cells sense local ammonia and directly modify neurotransmission by releasing GABA.
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Affiliation(s)
- David E. Fried
- 1Neuroscience Program and Department of Physiology,
Michigan State University, East Lansing,
Michigan;
| | - Ralph E. Watson
- 2Department of Medicine, Michigan State
University, East Lansing, Michigan; and
| | - Simon C. Robson
- 3Divisions of Gastroenterology and Transplantation, Department
of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical
School, Boston, Massachusetts
| | - Brian D. Gulbransen
- 1Neuroscience Program and Department of Physiology,
Michigan State University, East Lansing,
Michigan;
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36
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Stefanits H, Milenkovic I, Mahr N, Pataraia E, Hainfellner JA, Kovacs GG, Sieghart W, Yilmazer-Hanke D, Czech T. GABAAreceptor subunits in the human amygdala and hippocampus: Immunohistochemical distribution of 7 subunits. J Comp Neurol 2017; 526:324-348. [DOI: 10.1002/cne.24337] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 09/12/2017] [Accepted: 09/19/2017] [Indexed: 12/18/2022]
Affiliation(s)
- Harald Stefanits
- Department of Neurosurgery; Medical University of Vienna; Vienna Austria
- Institute of Neurology, Medical University of Vienna; Vienna Austria
| | - Ivan Milenkovic
- Department of Clinical Neurology; Medical University of Vienna; Vienna Austria
| | - Nina Mahr
- Department of Neurosurgery; Medical University of Vienna; Vienna Austria
| | - Ekaterina Pataraia
- Department of Clinical Neurology; Medical University of Vienna; Vienna Austria
| | | | - Gabor G. Kovacs
- Institute of Neurology, Medical University of Vienna; Vienna Austria
| | - Werner Sieghart
- Center for Brain Research, Department of Molecular Neurosciences; Medical University of Vienna; Vienna Austria
| | - Deniz Yilmazer-Hanke
- Clinical Neuroanatomy, Neurology Department, Medical Faculty; Ulm University; Ulm Germany
| | - Thomas Czech
- Department of Neurosurgery; Medical University of Vienna; Vienna Austria
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37
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Wang Y, Wu Z, Bai YT, Wu GY, Chen G. Gad67 haploinsufficiency reduces amyloid pathology and rescues olfactory memory deficits in a mouse model of Alzheimer's disease. Mol Neurodegener 2017; 12:73. [PMID: 29017573 PMCID: PMC5633901 DOI: 10.1186/s13024-017-0213-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 09/21/2017] [Indexed: 01/11/2023] Open
Abstract
Background Alzheimer’s disease (AD) is the most common age-related neurodegenerative disorder, affecting millions of people worldwide. Although dysfunction of multiple neurotransmitter systems including cholinergic, glutamatergic and GABAergic systems has been associated with AD progression the underlying mechanisms remain elusive. We and others have recently found that GABA content is elevated in AD brains and linked to cognitive deficits in AD mouse models. The glutamic acid decarboxylase 67 (GAD67) is the major enzyme converting glutamate into GABA and has been implied in a number of neurological disorders such as epilepsy and schizophrenia. However, whether Gad67 is involved in AD pathology has not been well studied. Here, we investigate the functional role of GAD67 in an AD mouse model with Gad67 haploinsufficiency that is caused by replacing one allele of Gad67 with green fluorescent protein (GFP) gene during generation of GAD67-GFP mice. Methods To genetically reduce GAD67 in AD mouse brains, we crossed the Gad67 haploinsufficient mice (GAD67-GFP+/−) with 5xFAD mice (harboring 5 human familial AD mutations in APP and PS1 genes) to generate a new line of bigenic mice. Immunostaining, ELISA, electrophysiology and behavior test were applied to compare the difference between groups. Results We found that reduction of GAD67 resulted in a significant decrease of amyloid β production in 5xFAD mice. Concurrently, the abnormal astrocytic GABA and tonic GABA currents, as well as the microglial reactivity were significantly reduced in the 5xFAD mice with Gad67 haploinsufficiency. Importantly, the olfactory memory deficit of 5xFAD mice was rescued by Gad67 haploinsufficiency. Conclusions Our results demonstrate that GAD67 plays an important role in AD pathology, suggesting that GAD67 may be a potential drug target for modulating the progress of AD. Electronic supplementary material The online version of this article (doi: 10.1186/s13024-017-0213-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yue Wang
- Department of Biology, Huck Institutes of Life Sciences, Pennsylvania State University, University park, PA, 16802, USA
| | - Zheng Wu
- Department of Biology, Huck Institutes of Life Sciences, Pennsylvania State University, University park, PA, 16802, USA.
| | - Yu-Ting Bai
- Department of Biology, Huck Institutes of Life Sciences, Pennsylvania State University, University park, PA, 16802, USA
| | - Gang-Yi Wu
- Department of Biology, Huck Institutes of Life Sciences, Pennsylvania State University, University park, PA, 16802, USA. .,School of Life Science, South China Normal University, Guangzhou, 510631, China.
| | - Gong Chen
- Department of Biology, Huck Institutes of Life Sciences, Pennsylvania State University, University park, PA, 16802, USA.
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38
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Min JO, Yoon BE. Glia and gliotransmitters on carbon nanotubes. NANO REVIEWS & EXPERIMENTS 2017; 8:1323853. [PMID: 30410703 PMCID: PMC6167025 DOI: 10.1080/20022727.2017.1323853] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 11/20/2016] [Accepted: 05/11/2017] [Indexed: 11/11/2022]
Abstract
Introduction: Functionalised carbon nanotubes (CNTs) have been shown to be promising biomaterials in neural systems, such as CNT -based nerve scaffolds to drive nerve regeneration. CNTs have been shown to modulate neuronal growth and improve electrical conductivity of neurons. Methods: Cultured astrocytes on the functionalized CNTs (PEG, caroboxyl group) were assessed for distribution of GABA, glutamate uptake assay using isotope and change of conductance of CNTs by ATP. Immunostaining of GABA using anti-GABA (red), anti-GFAP (green) antibody in primary cortical astrocytes on MW-CNT and PDL coverslips. Results: The functionalization of CNTs has improved their solubility and biocompatibility and alters their cellular interaction pathways. Recently, CNTs have been shown to modulate morphofunctional characteristics of glia as well as neurons. Among the various types of glia, astrocytes express diverse receptors for corresponding neurotransmitters and release gliotransmitters, including glutamate, adenosine triphosphate, and γ-amino butyric acid. Gliotransmitters are primarily released from astrocytes and play important roles in glia–neuron crosstalk. Conclusion: This review focuses on the effects of CNTs on glial cells and discusses how functionalized CNTs can modulate morphology and gliotransmitters of glial cells. Based on exciting new findings, they look to be a promising material for use in brain disease therapy or neuroprosthetics.
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Affiliation(s)
- Joo-Ok Min
- Department of Nanobiomedical Science, Dankook University, Cheonan-si, Chungnam, Republic of Korea
| | - Bo-Eun Yoon
- Department of Nanobiomedical Science, Dankook University, Cheonan-si, Chungnam, Republic of Korea.,Department of Molecular Biology, Dankook University, Cheonan-si, Chungnam, Republic of Korea
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Xu Z, Liu Y, Wei P, Feng K, Niu J, Shen G, Lu W, Xiao W, Wang J, Smagghe GJ, Xu Q, He L. High Gama-Aminobutyric Acid Contents Involved in Abamectin Resistance and Predation, an Interesting Phenomenon in Spider Mites. Front Physiol 2017; 8:216. [PMID: 28443033 PMCID: PMC5387048 DOI: 10.3389/fphys.2017.00216] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 03/24/2017] [Indexed: 12/14/2022] Open
Abstract
Abamectin has been widely used as an insecticide/acaricide for more than 30 years because of its superior bioactivity. Recently, an interesting phenomenon was identified in the carmine spider mite, Tetranychus cinnabarinus, an important pest in agriculture. The gamma aminobutyric acid (GABA) contents in a laboratory abamectin resistant strain of T. cinnabarinus (AbR) were significantly increased. Decreases in activity and mRNA expression of GABA transaminase (GABA-T) were responsible for GABA accumulation in AbR mites. To clarify the mechanism of GABA accumulation mediated abamectin resistance, three artificial approaches were conducted to increase GABA contents in susceptible mites, including feeding of vigabatrin (a specific inhibitor of GABA-T), feeding of exogenous GABA, and inhibition of GABA-T gene expression. The results showed that susceptible mites developed resistance to abamectin when the GABA contents were artificially increased. We also observed that the mites with higher GABA contents moved more slowly, which is consistent with the fact that GABA is an inhibitory neurotransmitter in arthropods. Subsequently, functional response assays revealed that predation rates of predatory mites on GABA accumulated abamectin-resistant mites were much higher than control groups. The tolerance to abamectin, slow crawling speed, and vulnerability to predators were all resulted from GABA accumulation. This relationship between GABA and predation was also confirmed in a field-collected population. Our finding indicates that predatory mites might be used as a tool for biological control to circumvent the development of abamectin resistance in mites.
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Affiliation(s)
- Zhifeng Xu
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
| | - Yanchao Liu
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
| | - Peng Wei
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
| | - Kaiyang Feng
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
| | - Jinzhi Niu
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
| | - Guangmao Shen
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
| | - Wencai Lu
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
| | - Wei Xiao
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
| | - Jinjun Wang
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
| | - Guy J Smagghe
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China.,Department of Crop Protection, Faculty of Bioscience Engineering, Ghent UniversityGhent, Belgium
| | - Qiang Xu
- Department of Biology, Abilene Christian UniversityAbilene, TX, USA
| | - Lin He
- Key Laboratory of Entomology and Pest Control Engineering of Chongqing, College of Plant Protection, Southwest UniversityChongqing, China
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Kardos J, Héja L, Jemnitz K, Kovács R, Palkovits M. The nature of early astroglial protection-Fast activation and signaling. Prog Neurobiol 2017; 153:86-99. [PMID: 28342942 DOI: 10.1016/j.pneurobio.2017.03.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 09/22/2016] [Accepted: 03/05/2017] [Indexed: 12/14/2022]
Abstract
Our present review is focusing on the uniqueness of balanced astroglial signaling. The balance of excitatory and inhibitory signaling within the CNS is mainly determined by sharp synaptic transients of excitatory glutamate (Glu) and inhibitory γ-aminobutyrate (GABA) acting on the sub-second timescale. Astroglia is involved in excitatory chemical transmission by taking up i) Glu through neurotransmitter-sodium transporters, ii) K+ released due to presynaptic action potential generation, and iii) water keeping osmotic pressure. Glu uptake-coupled Na+ influx may either ignite long-range astroglial Ca2+ transients or locally counteract over-excitation via astroglial GABA release and increased tonic inhibition. Imbalance of excitatory and inhibitory drives is associated with a number of disease conditions, including prevalent traumatic and ischaemic injuries or the emergence of epilepsy. Therefore, when addressing the potential of early therapeutic intervention, astroglial signaling functions combating progress of Glu excitotoxicity is of critical importance. We suggest, that excitotoxicity is linked primarily to over-excitation induced by the impairment of astroglial Glu uptake and/or GABA release. Within this framework, we discuss the acute alterations of Glu-cycling and metabolism and conjecture the therapeutic promise of regulation. We also confer the role played by key carrier proteins and enzymes as well as their interplay at the molecular, cellular, and organ levels. Moreover, based on our former studies, we offer potential prospect on the emerging theme of astroglial succinate sensing in course of Glu excitotoxicity.
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Affiliation(s)
- Julianna Kardos
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Hungary.
| | - László Héja
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Hungary
| | - Katalin Jemnitz
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Hungary
| | - Richárd Kovács
- Institute of Neurophysiology, Charité - Universitätsmedizin, Berlin, Germany
| | - Miklós Palkovits
- Human Brain Tissue Bank and Laboratory, Semmelweis University, Budapest, Hungary
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Dossi E, Vasile F, Rouach N. Human astrocytes in the diseased brain. Brain Res Bull 2017; 136:139-156. [PMID: 28212850 PMCID: PMC5766741 DOI: 10.1016/j.brainresbull.2017.02.001] [Citation(s) in RCA: 154] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 02/08/2017] [Accepted: 02/09/2017] [Indexed: 12/23/2022]
Abstract
Astrocytes are key active elements of the brain that contribute to information processing. They not only provide neurons with metabolic and structural support, but also regulate neurogenesis and brain wiring. Furthermore, astrocytes modulate synaptic activity and plasticity in part by controlling the extracellular space volume, as well as ion and neurotransmitter homeostasis. These findings, together with the discovery that human astrocytes display contrasting characteristics with their rodent counterparts, point to a role for astrocytes in higher cognitive functions. Dysfunction of astrocytes can thereby induce major alterations in neuronal functions, contributing to the pathogenesis of several brain disorders. In this review we summarize the current knowledge on the structural and functional alterations occurring in astrocytes from the human brain in pathological conditions such as epilepsy, primary tumours, Alzheimer's disease, major depressive disorder and Down syndrome. Compelling evidence thus shows that dysregulations of astrocyte functions and interplay with neurons contribute to the development and progression of various neurological diseases. Targeting astrocytes is thus a promising alternative approach that could contribute to the development of novel and effective therapies to treat brain disorders.
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Affiliation(s)
- Elena Dossi
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.
| | - Flora Vasile
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.
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42
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Kunisawa K, Kido K, Nakashima N, Matsukura T, Nabeshima T, Hiramatsu M. Betaine attenuates memory impairment after water-immersion restraint stress and is regulated by the GABAergic neuronal system in the hippocampus. Eur J Pharmacol 2017; 796:122-130. [DOI: 10.1016/j.ejphar.2016.12.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 12/03/2016] [Accepted: 12/05/2016] [Indexed: 02/05/2023]
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43
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Sherwood MW, Arizono M, Hisatsune C, Bannai H, Ebisui E, Sherwood JL, Panatier A, Oliet SHR, Mikoshiba K. Astrocytic IP 3 Rs: Contribution to Ca 2+ signalling and hippocampal LTP. Glia 2017; 65:502-513. [PMID: 28063222 DOI: 10.1002/glia.23107] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Revised: 11/26/2016] [Accepted: 12/01/2016] [Indexed: 12/22/2022]
Abstract
Astrocytes regulate hippocampal synaptic plasticity by the Ca2+ dependent release of the N-methyl d-aspartate receptor (NMDAR) co-agonist d-serine. Previous evidence indicated that d-serine release would be regulated by the intracellular Ca2+ release channel IP3 receptor (IP3 R), however, genetic deletion of IP3 R2, the putative astrocytic IP3 R subtype, had no impact on synaptic plasticity or transmission. Although IP3 R2 is widely believed to be the only functional IP3 R in astrocytes, three IP3 R subtypes (1, 2, and 3) have been identified in vertebrates. Therefore, to better understand gliotransmission, we investigated the functionality of IP3 R and the contribution of the three IP3 R subtypes to Ca2+ signalling. As a proxy for gliotransmission, we found that long-term potentiation (LTP) was impaired by dialyzing astrocytes with the broad IP3 R blocker heparin, and rescued by exogenous d-serine, indicating that astrocytic IP3 Rs regulate d-serine release. To explore which IP3 R subtypes are functional in astrocytes, we used pharmacology and two-photon Ca2+ imaging of hippocampal slices from transgenic mice (IP3 R2-/- and IP3 R2-/- ;3-/- ). This approach revealed that underneath IP3 R2-mediated global Ca2+ events are an overlooked class of IP3 R-mediated local events, occurring in astroglial processes. Notably, multiple IP3 Rs were recruited by high frequency stimulation of the Schaffer collaterals, a classical LTP induction protocol. Together, these findings show the dependence of LTP and gliotransmission on Ca2+ release by astrocytic IP3 Rs. GLIA 2017;65:502-513.
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Affiliation(s)
- Mark William Sherwood
- INSERM U1215, Neurocentre Magendie, Bordeaux, 33077, France.,Université de Bordeaux, Bordeaux, 33077, France.,Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Misa Arizono
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Chihiro Hisatsune
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Hiroko Bannai
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.,Division of Biological Sciences, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, 464-8602, Japan
| | - Etsuko Ebisui
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - John Lawrence Sherwood
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Aude Panatier
- INSERM U1215, Neurocentre Magendie, Bordeaux, 33077, France.,Université de Bordeaux, Bordeaux, 33077, France
| | | | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
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Glial GABA Transporters as Modulators of Inhibitory Signalling in Epilepsy and Stroke. ADVANCES IN NEUROBIOLOGY 2017; 16:137-167. [PMID: 28828609 DOI: 10.1007/978-3-319-55769-4_7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Imbalances in GABA-mediated tonic inhibition are involved in several pathophysiological conditions. A classical way of controlling tonic inhibition is through pharmacological intervention with extrasynaptic GABAA receptors that sense ambient GABA and mediate a persistent GABAergic conductance. An increase in tonic inhibition may, however, also be obtained indirectly by inhibiting glial GABA transporters (GATs). These are sodium-coupled membrane transport proteins that normally act to terminate GABA neurotransmitter action by taking up GABA into surrounding astrocytes. The aim of the review is to provide an overview of glial GATs in regulating tonic inhibition, especially in epilepsy and stroke. This entails a comprehensive summary of changes known to occur in GAT expression levels and signalling following epileptic and ischemic insults. Further, we discuss the accumulating pharmacological evidence for targeting GATs in these diseases.
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45
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Untiet V, Kovermann P, Gerkau NJ, Gensch T, Rose CR, Fahlke C. Glutamate transporter-associated anion channels adjust intracellular chloride concentrations during glial maturation. Glia 2016; 65:388-400. [PMID: 27859594 DOI: 10.1002/glia.23098] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 10/18/2016] [Accepted: 10/24/2016] [Indexed: 01/09/2023]
Abstract
Astrocytic volume regulation and neurotransmitter uptake are critically dependent on the intracellular anion concentration, but little is known about the mechanisms controlling internal anion homeostasis in these cells. Here we used fluorescence lifetime imaging microscopy (FLIM) with the chloride-sensitive dye MQAE to measure intracellular chloride concentrations in murine Bergmann glial cells in acute cerebellar slices. We found Bergmann glial [Cl- ]int to be controlled by two opposing transport processes: chloride is actively accumulated by the Na+ -K+ -2Cl- cotransporter NKCC1, and chloride efflux through anion channels associated with excitatory amino acid transporters (EAATs) reduces [Cl- ]int to values that vary upon changes in expression levels or activity of these channels. EAATs transiently form anion-selective channels during glutamate transport, and thus represent a class of ligand-gated anion channels. Age-dependent upregulation of EAATs results in a developmental chloride switch from high internal chloride concentrations (51.6 ± 2.2 mM, mean ± 95% confidence interval) during early development to adult levels (35.3 ± 0.3 mM). Simultaneous blockade of EAAT1/GLAST and EAAT2/GLT-1 increased [Cl- ]int in adult glia to neonatal values. Moreover, EAAT activation by synaptic stimulations rapidly decreased [Cl- ]int . Other tested chloride channels or chloride transporters do not contribute to [Cl- ]int under our experimental conditions. Neither genetic removal of ClC-2 nor pharmacological block of K+ -Cl- cotransporter change resting Bergmann glial [Cl- ]int in acute cerebellar slices. We conclude that EAAT anion channels play an important and unexpected role in adjusting glial intracellular anion concentration during maturation and in response to cerebellar activity. GLIA 2017;65:388-400.
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Affiliation(s)
- Verena Untiet
- Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, Germany
| | - Peter Kovermann
- Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, Germany
| | - Niklas J Gerkau
- Institute of Neurobiology, Heinrich-Heine-Universität Düsseldorf, Germany
| | - Thomas Gensch
- Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, Germany
| | - Christine R Rose
- Institute of Neurobiology, Heinrich-Heine-Universität Düsseldorf, Germany
| | - Christoph Fahlke
- Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, Germany
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Urrutia M, Fernández S, González M, Vilches R, Rojas P, Vásquez M, Kurte M, Vega-Letter AM, Carrión F, Figueroa F, Rojas P, Irarrázabal C, Fuentealba RA. Overexpression of Glutamate Decarboxylase in Mesenchymal Stem Cells Enhances Their Immunosuppressive Properties and Increases GABA and Nitric Oxide Levels. PLoS One 2016; 11:e0163735. [PMID: 27662193 PMCID: PMC5035029 DOI: 10.1371/journal.pone.0163735] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 09/13/2016] [Indexed: 12/12/2022] Open
Abstract
The neurotransmitter GABA has been recently identified as a potent immunosuppressive agent that targets both innate and adaptive immune systems and prevents disease progression of several autoimmunity models. Mesenchymal stem cells (MSCs) are self-renewing progenitor cells that differentiate into various cell types under specific conditions, including neurons. In addition, MSC possess strong immunosuppressive capabilities. Upon cytokine priming, undifferentiated MSC suppress T-cell proliferation via cell-to-cell contact mechanisms and the secretion of soluble factors like nitric oxide, prostaglandin E2 and IDO. Although MSC and MSC-derived neuron-like cells express some GABAergic markers in vitro, the role for GABAergic signaling in MSC-mediated immunosuppression remains completely unexplored. Here, we demonstrate that pro-inflammatory cytokines selectively regulate GAD-67 expression in murine bone marrow-MSC. However, expression of GAD-65 is required for maximal GABA release by MSC. Gain of function experiments using GAD-67 and GAD-65 co-expression demonstrates that GAD increases immunosuppressive function in the absence of pro-inflammatory licensing. Moreover, GAD expression in MSC evokes an increase in both GABA and NO levels in the supernatants of co-cultured MSC with activated splenocytes. Notably, the increase in NO levels by GAD expression was not observed in cultures of isolated MSC expressing GAD, suggesting crosstalk between these two pathways in the setting of immunosuppression. These results indicate that GAD expression increases MSC-mediated immunosuppression via secretion of immunosuppressive agents. Our findings may help reconsider GABAergic activation in MSC for immunological disorders.
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Affiliation(s)
- Mariana Urrutia
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Sebastián Fernández
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Marisol González
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Rodrigo Vilches
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Pablo Rojas
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Manuel Vásquez
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Mónica Kurte
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Ana María Vega-Letter
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Flavio Carrión
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Fernando Figueroa
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Patricio Rojas
- Departamento de Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Carlos Irarrázabal
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Rodrigo A. Fuentealba
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
- * E-mail:
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Wang L, Wang Y, Zhou S, Yang L, Shi Q, Li Y, Zhang K, Yang L, Zhao M, Yang Q. Imbalance between Glutamate and GABA in Fmr1 Knockout Astrocytes Influences Neuronal Development. Genes (Basel) 2016; 7:genes7080045. [PMID: 27517961 PMCID: PMC4999833 DOI: 10.3390/genes7080045] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 07/16/2016] [Accepted: 07/25/2016] [Indexed: 01/21/2023] Open
Abstract
Fragile X syndrome (FXS) is a form of inherited mental retardation that results from the absence of the fragile X mental retardation protein (FMRP), the product of the Fmr1 gene. Numerous studies have shown that FMRP expression in astrocytes is important in the development of FXS. Although astrocytes affect neuronal dendrite development in Fmr1 knockout (KO) mice, the factors released by astrocytes are still unclear. We cultured wild type (WT) cortical neurons in astrocyte-conditioned medium (ACM) from WT or Fmr1 KO mice. Immunocytochemistry and Western blotting were performed to detect the dendritic growth of both WT and KO neurons. We determined glutamate and γ-aminobutyric acid (GABA) levels using high-performance liquid chromatography (HPLC). The total neuronal dendritic length was reduced when cultured in the Fmr1 KO ACM. This neurotoxicity was triggered by an imbalanced release of glutamate and GABA from Fmr1 KO astrocytes. We found increased glutaminase and GABA transaminase (GABA-T) expression and decreased monoamine oxidase B expression in Fmr1 KO astrocytes. The elevated levels of glutamate contributed to oxidative stress in the cultured neurons. Vigabatrin (VGB), a GABA-T inhibitor, reversed the changes caused by glutamate and GABA release in Fmr1 KO astrocytes and the abnormal behaviors in Fmr1 KO mice. Our results indicate that the imbalance in the astrocytic glutamate and GABA release may be involved in the neuropathology and the underlying symptoms of FXS, and provides a therapeutic target for treatment.
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Affiliation(s)
- Lu Wang
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China.
| | - Yan Wang
- Department of Gastroenterology and Endoscopy Center, No. 323 Hospital of PLA, Xi'an 710054, China.
| | - Shimeng Zhou
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China.
| | - Liukun Yang
- Fifth Company, Second Battalion, Cadet Brigade, Fourth Military Medical University, Xi'an 710032, China.
| | - Qixin Shi
- Fifth Company, Second Battalion, Cadet Brigade, Fourth Military Medical University, Xi'an 710032, China.
| | - Yujiao Li
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China.
| | - Kun Zhang
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China.
| | - Le Yang
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China.
| | - Minggao Zhao
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China.
| | - Qi Yang
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China.
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Wang C, Chen H, Zhang M, Zhang J, Wei X, Ying W. Malate-aspartate shuttle inhibitor aminooxyacetic acid leads to decreased intracellular ATP levels and altered cell cycle of C6 glioma cells by inhibiting glycolysis. Cancer Lett 2016; 378:1-7. [PMID: 27157912 DOI: 10.1016/j.canlet.2016.05.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 05/02/2016] [Accepted: 05/03/2016] [Indexed: 01/08/2023]
Abstract
NADH shuttles, including malate-aspartate shuttle (MAS) and glycerol-3-phosphate shuttle, can shuttle the reducing equivalents of cytosolic NADH into mitochondria. It is widely accepted that the major function of NADH shuttles is to increase mitochondrial energy production. Our study tested the hypothesis that the novel major function of NADH shuttles in cancer cells is to maintain glycolysis by decreasing cytosolic NADH/NAD(+) ratios. We found that AOAA, a widely used MAS inhibitor, led to decreased intracellular ATP levels, altered cell cycle and increased apoptosis and necrosis of C6 glioma cells, without affecting the survival of primary astrocyte cultures. AOAA also decreased the glycolytic rate and the levels of extracellular lactate and pyruvate, without affecting the mitochondrial membrane potential of C6 cells. Moreover, the toxic effects of AOAA were completely prevented by pyruvate treatment. Collectively, our study has suggested that AOAA may be used to selectively decrease glioma cell survival, and the major function of MAS in cancer cells may be profoundly different from its major function in normal cells: The major function of MAS in cancer cells is to maintain glycolysis, instead of increasing mitochondrial energy metabolism.
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Affiliation(s)
- Caixia Wang
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Heyu Chen
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Mingchao Zhang
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Jie Zhang
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Xunbin Wei
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Weihai Ying
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China; Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200030, China.
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49
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Chiarini A, Armato U, Liu D, Dal Prà I. Calcium-Sensing Receptors of Human Neural Cells Play Crucial Roles in Alzheimer's Disease. Front Physiol 2016; 7:134. [PMID: 27199760 PMCID: PMC4844916 DOI: 10.3389/fphys.2016.00134] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 03/28/2016] [Indexed: 12/21/2022] Open
Abstract
In aged subjects, late-onset Alzheimer's disease (LOAD) starts in the lateral entorhinal allocortex where a failure of clearance mechanisms triggers an accumulation of neurotoxic amyloid-β42 oligomers (Aβ42-os). In neurons and astrocytes, Aβ42-os enhance the transcription of Aβ precursor protein (APP) and β-secretase/BACE1 genes. Thus, by acting together with γ-secretase, the surpluses of APP and BACE1 amplify the endogenous production of Aβ42-os which pile up, damage mitochondria, and are oversecreted. At the plasmalemma, exogenous Aβ42-os bind neurons' and astrocytes' calcium-sensing receptors (CaSRs) activating a set of intracellular signaling pathways which upkeep Aβ42-os intracellular accumulation and oversecretion by hindering Aβ42-os proteolysis. In addition, Aβ42-os accumulating in the extracellular milieu spread and reach mounting numbers of adjacent and remoter teams of neurons and astrocytes which in turn are recruited, again via Aβ42-os•CaSR-governed mechanisms, to produce and release additional Aβ42-os amounts. This relentless self-sustaining mechanism drives AD progression toward upper cortical areas. Later on accumulating Aβ42-os elicit the advent of hyperphosphorylated (p)-Tau oligomers which acting together with Aβ42-os and other glial neurotoxins cooperatively destroy wider and wider cognition-related cortical areas. In parallel, Aβ42-os•CaSR signals also elicit an excess production and secretion of nitric oxide and vascular endothelial growth factor-A from astrocytes, of Aβ42-os and myelin basic protein from oligodendrocytes, and of proinflammatory cytokines, nitric oxide and (likely) Aβ42-os from microglia. Activated astrocytes and microglia survive the toxic onslaught, whereas neurons and oligodendrocytes increasingly die. However, we have shown that highly selective allosteric CaSR antagonists (calcilytics), like NPS 2143 and NPS 89626, efficiently suppress all the neurotoxic effects Aβ42-os•CaSR signaling drives in cultured cortical untransformed human neurons and astrocytes. In fact, calcilytics increase Aβ42 proteolysis and discontinue the oversecretion of Aβ42-os, nitric oxide, and vascular endothelial growth factor-A from both astrocytes and neurons. Seemingly, calcilytics would also benefit the other types of glial cells and cerebrovascular cells otherwise damaged by the effects of Aβ42-os•CaSR signaling. Thus, given at amnestic minor cognitive impairment (aMCI) or initial symptomatic stages, calcilytics could prevent or terminate the propagation of LOAD neuropathology and preserve human neurons' viability and hence patients' cognitive abilities.
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Affiliation(s)
- Anna Chiarini
- Human Histology and Embryology Unit, University of Verona Medical SchoolVerona, Italy
| | - Ubaldo Armato
- Human Histology and Embryology Unit, University of Verona Medical SchoolVerona, Italy
| | - Daisong Liu
- Human Histology and Embryology Unit, University of Verona Medical SchoolVerona, Italy
- Proteomics Laboratory, Institute for Burn Research, Third Military Medical UniversityChongqing, China
| | - Ilaria Dal Prà
- Human Histology and Embryology Unit, University of Verona Medical SchoolVerona, Italy
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50
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Yelkenli İH, Ulupinar E, Korkmaz OT, Şener E, Kuş G, Filiz Z, Tunçel N. Modulation of Corpus Striatal Neurochemistry by Astrocytes and Vasoactive Intestinal Peptide (VIP) in Parkinsonian Rats. J Mol Neurosci 2016; 59:280-9. [DOI: 10.1007/s12031-016-0757-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 04/11/2016] [Indexed: 12/29/2022]
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