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Barbaresi P, Fabri M, Lorenzi T, Sagrati A, Morroni M. Intrinsic organization of the corpus callosum. Front Physiol 2024; 15:1393000. [PMID: 39035452 PMCID: PMC11259024 DOI: 10.3389/fphys.2024.1393000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 05/16/2024] [Indexed: 07/23/2024] Open
Abstract
The corpus callosum-the largest commissural fiber system connecting the two cerebral hemispheres-is considered essential for bilateral sensory integration and higher cognitive functions. Most studies exploring the corpus callosum have examined either the anatomical, physiological, and neurochemical organization of callosal projections or the functional and/or behavioral aspects of the callosal connections after complete/partial callosotomy or callosal lesion. There are no works that address the intrinsic organization of the corpus callosum. We review the existing information on the activities that take place in the commissure in three sections: I) the topographical and neurochemical organization of the intracallosal fibers, II) the role of glia in the corpus callosum, and III) the role of the intracallosal neurons.
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Affiliation(s)
- Paolo Barbaresi
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Marche Polytechnic University, Ancona, Italy
| | - Mara Fabri
- Department of Life and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Teresa Lorenzi
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Marche Polytechnic University, Ancona, Italy
| | - Andrea Sagrati
- Department of Life and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Manrico Morroni
- Electron Microscopy Unit, Azienda Ospedaliero-Universitaria, Ancona, Italy
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2
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Yang Y, Hang W, Li J, Liu T, Hu Y, Fang F, Yan D, McQuillan PM, Wang M, Hu Z. Effect of General Anesthetic Agents on Microglia. Aging Dis 2024; 15:1308-1328. [PMID: 37962460 PMCID: PMC11081156 DOI: 10.14336/ad.2023.1108] [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: 09/07/2023] [Accepted: 11/08/2023] [Indexed: 11/15/2023] Open
Abstract
The effects of general anesthetic agents (GAAs) on microglia and their potential neurotoxicity have attracted the attention of neuroscientists. Microglia play important roles in the inflammatory process and in neuromodulation of the central nervous system. Microglia-mediated neuroinflammation is a key mechanism of neurocognitive dysfunction during the perioperative period. Microglial activation by GAAs induces anti-inflammatory and pro-inflammatory effects in microglia, suggesting that GAAs play a dual role in the mechanism of postoperative cognitive dysfunction. Understanding of the mechanisms by which GAAs regulate microglia may help to reduce the incidence of postoperative adverse effects. Here, we review the actions of GAAs on microglia and the consequent changes in microglial function. We summarize clinical and animal studies associating microglia with general anesthesia and describe how GAAs interact with neurons via microglia to further explore the mechanisms of action of GAAs in the nervous system.
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Affiliation(s)
- Yanchang Yang
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Wenxin Hang
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Jun Li
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
- Department of Anesthesiology, Shulan (Hangzhou) Hospital Affiliated to Zhejiang Shuren University Shulan International Medical College, Hangzhou, China.
| | - Tiantian Liu
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
- Department of Anesthesiology, Ningbo Women and Children's Hospital, Ningbo, China.
| | - Yuhan Hu
- Cell Biology Department, Yale University, New Haven, CT, USA.
| | - Fuquan Fang
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Dandan Yan
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Patrick M. McQuillan
- Department of Anesthesiology, Penn State Hershey Medical Center, Penn State College of Medicine, Hershey, PA, USA.
| | - Mi Wang
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Zhiyong Hu
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
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3
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VanderZwaag J, Halvorson T, Dolhan K, Šimončičová E, Ben-Azu B, Tremblay MÈ. The Missing Piece? A Case for Microglia's Prominent Role in the Therapeutic Action of Anesthetics, Ketamine, and Psychedelics. Neurochem Res 2023; 48:1129-1166. [PMID: 36327017 DOI: 10.1007/s11064-022-03772-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 08/25/2022] [Accepted: 09/27/2022] [Indexed: 11/06/2022]
Abstract
There is much excitement surrounding recent research of promising, mechanistically novel psychotherapeutics - psychedelic, anesthetic, and dissociative agents - as they have demonstrated surprising efficacy in treating central nervous system (CNS) disorders, such as mood disorders and addiction. However, the mechanisms by which these drugs provide such profound psychological benefits are still to be fully elucidated. Microglia, the CNS's resident innate immune cells, are emerging as a cellular target for psychiatric disorders because of their critical role in regulating neuroplasticity and the inflammatory environment of the brain. The following paper is a review of recent literature surrounding these neuropharmacological therapies and their demonstrated or hypothesized interactions with microglia. Through investigating the mechanism of action of psychedelics, such as psilocybin and lysergic acid diethylamide, ketamine, and propofol, we demonstrate a largely under-investigated role for microglia in much of the emerging research surrounding these pharmacological agents. Among others, we detail sigma-1 receptors, serotonergic and γ-aminobutyric acid signalling, and tryptophan metabolism as pathways through which these agents modulate microglial phagocytic activity and inflammatory mediator release, inducing their therapeutic effects. The current review includes a discussion on future directions in the field of microglial pharmacology and covers bidirectional implications of microglia and these novel pharmacological agents in aging and age-related disease, glial cell heterogeneity, and state-of-the-art methodologies in microglial research.
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Affiliation(s)
- Jared VanderZwaag
- Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Torin Halvorson
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
- BC Children's Hospital Research Institute, Vancouver, BC, Canada
| | - Kira Dolhan
- Department of Psychology, University of Victoria, Vancouver, BC, Canada
- Department of Biology, University of Victoria, Vancouver, BC, Canada
| | - Eva Šimončičová
- Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Benneth Ben-Azu
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Department of Pharmacology, Faculty of Basic Medical Sciences, College of Health Sciences, Delta State University, Abraka, Delta State, Nigeria
| | - Marie-Ève Tremblay
- Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada.
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada.
- Axe Neurosciences, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada.
- Neurology and Neurosurgery Department, McGill University, Montreal, QC, Canada.
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
- Institute for Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
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4
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Marcinkowska M, Mordyl B, Fajkis-Zajaczkowska N, Siwek A, Karcz T, Gawalska A, Bucki A, Żmudzki P, Partyka A, Jastrzębska-Więsek M, Pomierny B, Walczak M, Smolik M, Pytka K, Mika K, Kotańska M, Kolaczkowski M. Hybrid molecules combining GABA-A and serotonin 5-HT 6 receptors activity designed to tackle neuroinflammation associated with depression. Eur J Med Chem 2023; 247:115071. [PMID: 36603509 DOI: 10.1016/j.ejmech.2022.115071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 12/22/2022] [Accepted: 12/28/2022] [Indexed: 12/31/2022]
Abstract
There is clear evidence that the presence of inflammatory factors and impaired GABA-ergic neurotransmission in depressed patients is associated with poor clinical outcome. We designed hybrid molecules, bearing the GABA molecule assembled with chemical fragments that interact with the serotonin 5-HT6 receptor. Such a combination aimed to curb neuroinflammation, remodel GABA-ergic signaling, and provide antidepressant-like activity. The most promising hybrid 3B exerted nanomolar affinity for 5-HT6 receptors and exerted agonistic properties on GABA-A receptors. Developability studies conferred that 3B exerted favorable drug-like properties and optimal brain penetration. In in vivo studies, 3B exerted robust antidepressant-like activity and proved to be highly effective in reducing levels of oxidative stress markers and the pro-inflammatory cytokine IL-6. The inetersting pharmacological profile of 3B makes it a promising candidate for further development for depression associated with neuroinflammation.
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Affiliation(s)
- Monika Marcinkowska
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland.
| | - Barbara Mordyl
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | | | - Agata Siwek
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Tadeusz Karcz
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Alicja Gawalska
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Adam Bucki
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Paweł Żmudzki
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Anna Partyka
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | | | - Bartosz Pomierny
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Maria Walczak
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Magdalena Smolik
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Karolina Pytka
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Kamil Mika
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Magdalena Kotańska
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland
| | - Marcin Kolaczkowski
- Jagiellonian University Medical College, Faculty of Pharmacy, 9 Medyczna St., 30-688, Krakow, Poland; Adamed Pharma S.A., Pienkow, 6A Mariana Adamkiewicza St., 05-152, Czosnów, Poland
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5
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Andoh M, Koyama R. Microglia and GABA: Diverse functions of microglia beyond GABA-receiving cells. Neurosci Res 2023; 187:52-57. [PMID: 36152917 DOI: 10.1016/j.neures.2022.09.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 09/19/2022] [Indexed: 11/18/2022]
Abstract
Neurotransmitters modulate intracellular signaling not only in neurons but also in glial cells such as astrocytes, which form tripartite synapses, and oligodendrocytes, which produce the myelin sheath on axons. Another major glial cell type, microglia, which are often referred to as brain-resident immune cells, also express receptors for neurotransmitters. Recent studies have mainly focused on excitatory neurotransmitters such as glutamate, and few have examined microglial responses to the inhibitory neurotransmitter GABA. Microglia can also structurally and functionally modulate inhibitory neuronal circuits, but the underlying molecular mechanisms remain largely unknown. Since the well-regulated balance of excitatory/inhibitory (E/I) neurotransmission is believed to be the basis of proper brain function, understanding how microglia regulate and respond to inhibitory neurotransmission will help us deepen our knowledge of neuron-glia interactions. In this review, we discuss the mechanisms by which GABA alters microglial behavior and the possibility that microglia are more than just GABA-receiving cells.
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Affiliation(s)
- Megumi Andoh
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Ryuta Koyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; Institute for AI and Beyond, The University of Tokyo, Tokyo 113-0033, Japan.
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6
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Michalettos G, Ruscher K. Crosstalk Between GABAergic Neurotransmission and Inflammatory Cascades in the Post-ischemic Brain: Relevance for Stroke Recovery. Front Cell Neurosci 2022; 16:807911. [PMID: 35401118 PMCID: PMC8983863 DOI: 10.3389/fncel.2022.807911] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 02/28/2022] [Indexed: 11/28/2022] Open
Abstract
Adaptive plasticity processes are required involving neurons as well as non-neuronal cells to recover lost brain functions after an ischemic stroke. Recent studies show that gamma-Aminobutyric acid (GABA) has profound effects on glial and immune cell functions in addition to its inhibitory actions on neuronal circuits in the post-ischemic brain. Here, we provide an overview of how GABAergic neurotransmission changes during the first weeks after stroke and how GABA affects functions of astroglial and microglial cells as well as peripheral immune cell populations accumulating in the ischemic territory and brain regions remote to the lesion. Moreover, we will summarize recent studies providing data on the immunomodulatory actions of GABA of relevance for stroke recovery. Interestingly, the activation of GABA receptors on immune cells exerts a downregulation of detrimental anti-inflammatory cascades. Conversely, we will discuss studies addressing how specific inflammatory cascades affect GABAergic neurotransmission on the level of GABA receptor composition, GABA synthesis, and release. In particular, the chemokines CXCR4 and CX3CR1 pathways have been demonstrated to modulate receptor composition and synthesis. Together, the actual view on the interactions between GABAergic neurotransmission and inflammatory cascades points towards a specific crosstalk in the post-ischemic brain. Similar to what has been shown in experimental models, specific therapeutic modulation of GABAergic neurotransmission and inflammatory pathways may synergistically promote neuronal plasticity to enhance stroke recovery.
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Affiliation(s)
- Georgios Michalettos
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Wallenberg Neuroscience Center, Lund University, Lund, Sweden
| | - Karsten Ruscher
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Wallenberg Neuroscience Center, Lund University, Lund, Sweden
- LUBIN Lab—Lunds Laboratorium för Neurokirurgisk Hjärnskadeforskning, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
- *Correspondence: Karsten Ruscher
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7
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GABAergic signaling by cells of the immune system: more the rule than the exception. Cell Mol Life Sci 2021; 78:5667-5679. [PMID: 34152447 PMCID: PMC8316187 DOI: 10.1007/s00018-021-03881-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/17/2021] [Accepted: 06/11/2021] [Indexed: 11/23/2022]
Abstract
Gamma-aminobutyric acid (GABA) is best known as an essential neurotransmitter in the evolved central nervous system (CNS) of vertebrates. However, GABA antedates the development of the CNS as a bioactive molecule in metabolism and stress-coupled responses of prokaryotes, invertebrates and plants. Here, we focus on the emerging findings of GABA signaling in the mammalian immune system. Recent reports show that mononuclear phagocytes and lymphocytes, for instance dendritic cells, microglia, T cells and NK cells, express a GABAergic signaling machinery. Mounting evidence shows that GABA receptor signaling impacts central immune functions, such as cell migration, cytokine secretion, immune cell activation and cytotoxic responses. Furthermore, the GABAergic signaling machinery of leukocytes is implicated in responses to microbial infection and is co-opted by protozoan parasites for colonization of the host. Peripheral GABA signaling is also implicated in inflammatory conditions and diseases, such as type 1 diabetes, rheumatoid arthritis and cancer cell metastasis. Adding to its role in neurotransmission, growing evidence shows that the non-proteinogenic amino acid GABA acts as an intercellular signaling molecule in the immune system and, as an interspecies signaling molecule in host–microbe interactions. Altogether, the data raise the assumption of conserved GABA signaling in a broad range of mammalian cells and diversification of function in the immune system.
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8
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Hadjihambi A, Karagiannis A, Theparambil SM, Ackland GL, Gourine AV. The effect of general anaesthetics on brain lactate release. Eur J Pharmacol 2020; 881:173188. [PMID: 32439258 PMCID: PMC7456770 DOI: 10.1016/j.ejphar.2020.173188] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 05/04/2020] [Accepted: 05/10/2020] [Indexed: 12/17/2022]
Abstract
The effects of anaesthetic agents on brain energy metabolism may explain their shared neurophysiological actions but remain poorly understood. The brain lactate shuttle hypothesis proposes that lactate, provided by astrocytes, is an important neuronal energy substrate. Here we tested the hypothesis that anaesthetic agents impair the brain lactate shuttle by interfering with astrocytic glycolysis. Lactate biosensors were used to record changes in lactate release by adult rat brainstem and cortical slices in response to thiopental, propofol and etomidate. Changes in cytosolic nicotinamide adenine dinucleotide reduced (NADH) and oxidized (NAD+) ratio as a measure of glycolytic rate were recorded in cultured astrocytes. It was found that in brainstem slices thiopental, propofol and etomidate reduced lactate release by 7.4 ± 3.6% (P < 0.001), 9.7 ± 6.6% (P < 0.001) and 8.0 ± 7.8% (P = 0.04), respectively. In cortical slices, thiopental reduced lactate release by 8.2 ± 5.6% (P = 0.002) and propofol by 6.0 ± 4.5% (P = 0.009). Lactate release in cortical slices measured during the light phase (period of sleep/low activity) was ~25% lower than that measured during the dark phase (period of wakefulness) (326 ± 83 μM vs 430 ± 118 μM, n = 10; P = 0.04). Thiopental and etomidate induced proportionally similar decreases in cytosolic [NADH]:[NAD+] ratio in astrocytes, indicative of a reduction in glycolytic rate. These data suggest that anaesthetic agents inhibit astrocytic glycolysis and reduce the level of extracellular lactate in the brain. Similar reductions in brain lactate release occur during natural state of sleep, suggesting that general anaesthesia may recapitulate some of the effects of sleep on brain energy metabolism.
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Affiliation(s)
- Anna Hadjihambi
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK; Department of Biomedical Sciences, University of Lausanne, Lausanne, 1005, Switzerland.
| | - Anastassios Karagiannis
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK
| | - Shefeeq M Theparambil
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK
| | - Gareth L Ackland
- Translational Medicine & Therapeutics, William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Alexander V Gourine
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK
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9
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Labrada-Moncada FE, Martínez-Torres A, Reyes-Haro D. GABA A Receptors are Selectively Expressed in NG2 Glia of the Cerebellar White Matter. Neuroscience 2020; 433:132-143. [PMID: 32171821 DOI: 10.1016/j.neuroscience.2020.03.003] [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: 07/17/2019] [Revised: 02/22/2020] [Accepted: 03/03/2020] [Indexed: 12/20/2022]
Abstract
The cerebellum is involved in the coordination of movement. Its cellular composition is dominated by GABAergic neuronal types, and glial cells are known to express functional receptors. GABAergic signaling regulates cell proliferation, differentiation, and migration during neurodevelopment. However, little is known about the functional expression of GABA receptors in the cerebellar white matter (WM). Thus, the aim of this study was to test whether glial cells express functional GABA receptors during postnatal development (P7-P9) of cerebellar WM. Immunofluorescence showed that half of the astrocytes express GAD67, suggesting that glial cells synthesize GABA. Calcium imaging in cerebellar slices revealed that GABA and the GABAA agonist muscimol evoked calcium transients in sulforhodamine B negative cells, whereas the GABAB agonist baclofen failed to evoke responses in cerebellar WM. Whole-cell patch-clamp recordings of GFAP+ cells showed dye coupling and a passive current-voltage relation typical of astrocytes. Surprisingly, these cells did not respond to muscimol. Two additional populations were identified as GFAP- cells. The first population showed dye coupling, slow decaying inward and outward currents with no voltage dependence, and did not respond to GABAA agonists. The second population showed an outward-rectifying current-voltage relationship and responded to muscimol, but dye coupling was absent. These cells received synaptic input and were NG2+, but evoked calcium waves failed to modulate the frequency of spontaneous postsynaptic currents (sPSCs) or signaling into NG2 glia. We conclude that GABAA receptor-mediated signaling is selective for NG2 glia in the WM of the cerebellum.
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Affiliation(s)
- Francisco Emmanuel Labrada-Moncada
- Departamento Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla 3001, Juriquilla, Querétaro CP76230, Mexico
| | - Ataúlfo Martínez-Torres
- Departamento Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla 3001, Juriquilla, Querétaro CP76230, Mexico
| | - Daniel Reyes-Haro
- Departamento Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla 3001, Juriquilla, Querétaro CP76230, Mexico.
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10
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Fattorini G, Catalano M, Melone M, Serpe C, Bassi S, Limatola C, Conti F. Microglial expression of GAT-1 in the cerebral cortex. Glia 2019; 68:646-655. [PMID: 31692106 DOI: 10.1002/glia.23745] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 10/12/2019] [Accepted: 10/18/2019] [Indexed: 01/08/2023]
Abstract
Microglial cells are the immune cells of the brain that, by sensing the microenvironment, permit a correct brain development and function. They communicate with other glial cells and with neurons, releasing and responding to a number of molecules that exert effects on surrounding cells. Among these, neurotransmitters and, in particular, gamma-aminobutyric acid (GABA) has recently gained interest in this context. We demonstrated the expression of GABA transporter 1 (GAT-1) in microglial cells both in soma and cell processes. We show that microglial cell treatment with 1,2,5,6-tetrahydro-1-[2-[[(diphenylmethylene)amino]oxy]ethyl]-3-pyridinecarboxylic acid hydrochloride (NNC-711), a potent and selective GAT-1 inhibitor, significantly reduced Na+ -dependent GABA uptake. On the other hand, GABA uptake was significantly increased by cell treatment with (S)-1-[2-[tris(4-methoxyphenyl)methoxy]ethyl]-3-piperidinecarboxylic acid (SNAP-5114), a GAT-2/3 inhibitor, and this effect was completely blocked by the botulinum toxin BoNT/C1, that specifically cleaves and inactives syntaxin 1A (STX1A). Overall, these findings show that microglial cells express GAT-1 and indicate that STX1A plays an important role in the regulation of GAT-1-dependent GABA uptake in microglia.
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Affiliation(s)
- Giorgia Fattorini
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Università Politecnica delle Marche, Ancona, Italy.,Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy
| | - Myriam Catalano
- Department of Physiology and Pharmacology, Sapienza University of Rome, Laboratory Affiliated to Istituto Pasteur Italia, Rome, Italy
| | - Marcello Melone
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Università Politecnica delle Marche, Ancona, Italy.,Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy
| | - Carmela Serpe
- Department of Physiology and Pharmacology, Sapienza University of Rome, Laboratory Affiliated to Istituto Pasteur Italia, Rome, Italy
| | - Silvia Bassi
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Università Politecnica delle Marche, Ancona, Italy
| | - Cristina Limatola
- Department of Physiology and Pharmacology, Sapienza University of Rome, Laboratory Affiliated to Istituto Pasteur Italia, Rome, Italy.,IRCCS Neuromed, Via Atinense, Pozzilli, Italy
| | - Fiorenzo Conti
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Università Politecnica delle Marche, Ancona, Italy.,Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy
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11
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Yan X, Li F, Maixner DW, Yadav R, Gao M, Ali MW, Hooks SB, Weng HR. Interleukin-1beta released by microglia initiates the enhanced glutamatergic activity in the spinal dorsal horn during paclitaxel-associated acute pain syndrome. Glia 2019; 67:482-497. [PMID: 30578561 DOI: 10.1002/glia.23557] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 10/08/2018] [Accepted: 10/08/2018] [Indexed: 01/30/2023]
Abstract
Patients receiving paclitaxel for cancer treatment often develop an acute pain syndrome (paclitaxel-associated acute pain syndrome, P-APS), which occurs immediately after paclitaxel treatment. Mechanisms underlying P-APS remain largely unknown. We recently reported that rodents receiving paclitaxel develop acute pain and activation of spinal microglial toll like receptor 4 (TLR4) by paclitaxel penetrating into the spinal cord is a critical event in the genesis of P-APS. Our current study dissected cellular and molecular mechanisms underlying the P-APS. We demonstrated that bath-perfusion of paclitaxel, at a concentration similar to that found in the cerebral spinal fluid in animals receiving i.v. paclitaxel (2 mg/kg), resulted in increased calcium activity in microglia instantly, and in astrocytes with 6 min delay. TLR4 activation in microglia by paclitaxel caused microglia to rapidly release interleukin-1β (IL-1β) but not tumor necrosis factor α, IL-6, or interferon-γ. IL-1β release from microglia depended on capthepsin B. IL-1β acted on astrocytes, leading to elevated calcium activity and suppressed glutamate uptake. IL-1β also acted on neurons to increase presynaptic glutamate release and postsynaptic AMPA receptor activity in the spinal dorsal horn. Knockout of IL-1 receptors prevented the development of acute pain induced by paclitaxel in mice. Our study indicates that IL-1β is a crucial molecule used by microglia to alter functions in astrocytes and neurons upon activation of TLR4 in the genesis of P-APS, and targeting the signaling pathways regulating the production and function of IL-1β from microglia is a potential avenue for the development of analgesics for the treatment of P-APS.
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Affiliation(s)
- Xisheng Yan
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, Athens, Georgia
- Department of Cardiovascular Medicine, Wuhan Third Hospital, Wuhan, China
| | - Fen Li
- Department of Neurology, Wuhan Third Hospital, Wuhan, China
| | - Dylan W Maixner
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, Athens, Georgia
| | - Ruchi Yadav
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, Athens, Georgia
| | - Mei Gao
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, Athens, Georgia
| | - Mourad Wagdy Ali
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, Athens, Georgia
| | - Shelley B Hooks
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, Athens, Georgia
| | - Han-Rong Weng
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, Athens, Georgia
- Department of Biomedical Sciences, Mercer University School of Medicine, Macon, Georgia
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12
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Parente A, Vállez García D, Shoji A, Lopes Alves I, Maas B, Zijlma R, Dierckx RA, Buchpiguel CA, de Vries EF, Doorduin J. Contribution of neuroinflammation to changes in [ 11C]flumazenil binding in the rat brain: Evaluation of the inflamed pons as reference tissue. Nucl Med Biol 2017; 49:50-56. [PMID: 28364664 DOI: 10.1016/j.nucmedbio.2017.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/09/2017] [Accepted: 03/10/2017] [Indexed: 11/17/2022]
Abstract
INTRODUCTION [11C]Flumazenil is a well-known PET tracer for GABAA receptors and is mainly used as an imaging biomarker for neuronal loss. Recently, GABAA receptors on immune cells have been investigated as target for modulation of inflammation. Since neuronal loss is often accompanied by neuroinflammation, PET imaging with [11C]flumazenil is potentially affected by infiltrating immune cells. This may also compromise the validity of using the pons as reference tissue in quantitative pharmacokinetic analysis. This study aims to evaluate whether inflammatory processes in the brain can influence [11C]flumazenil uptake and affect the outcome of pharmacokinetic modeling when the pons is used as reference tissue. METHODS The herpes simplex encephalitis (HSE) rat model is known to cause neuroinflammation in the brainstem. Dynamic [11C]flumazenil PET scans of 60-min, accompanied by arterial blood sampling and metabolite analysis, were acquired at day 6-7days post-infection of male Wistar rats (HSE, n=5 and control, n=6). Additionally, the GABAA receptor was saturated by injection of unlabeled flumazenil prior to the tracer injection in 4 rats per group. PET data were analyzed by pharmacokinetic modeling. RESULTS No statistically significant differences were found in the volume of distribution (VT) or non-displaceable binding potential (BPND) between control and HSE rats in any of the brain regions. Pre-saturation with unlabeled flumazenil resulted in a statistically significant reduction in [11C]flumazenil VT in all brain regions. The BPND obtained from SRTM exhibited a good correlation to DVR - 1 values from the two-tissue compartment model, coupled with some level of underestimation. CONCLUSION Reliable quantification of [11C]flumazenil binding in rats can be obtained by pharmacokinetic analysis using the pons as a pseudo-reference tissue even in the presence of strong acute neuroinflammation.
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Affiliation(s)
- Andrea Parente
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - David Vállez García
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Alexandre Shoji
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Center of Nuclear Medicine, University of Sao Paulo, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Isadora Lopes Alves
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Bram Maas
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Rolf Zijlma
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Rudi Ajo Dierckx
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Carlos A Buchpiguel
- Center of Nuclear Medicine, University of Sao Paulo, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Erik Fj de Vries
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Janine Doorduin
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
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Liu H, Leak RK, Hu X. Neurotransmitter receptors on microglia. Stroke Vasc Neurol 2016; 1:52-58. [PMID: 28959464 PMCID: PMC5435193 DOI: 10.1136/svn-2016-000012] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 04/29/2016] [Accepted: 04/30/2016] [Indexed: 12/21/2022] Open
Abstract
As the resident immune cells in the central nervous system, microglia have long been hypothesised to promote neuroinflammation and exacerbate neurotoxicity. However, this traditional view has undergone recent revision as evidence has accumulated that microglia exert beneficial and detrimental effects depending on activation status, polarisation phenotype and cellular context. A variety of neurotransmitter receptors are expressed on microglia and help mediate the bidirectional communication between neurons and microglia. Here we review data supporting the importance of neurotransmitter receptors on microglia, with a special emphasis on glutamate, γ-aminobutyric acid (GABA), norepinephrine, cannabinoid and acetylcholine receptors. We summarise evidence favouring a significant role for neurotransmitter receptors in modulating microglial activation, phagocytic clearance and phenotypic polarisation. Elucidating the effects of neurotransmitter receptors on microglia and dissecting the underlying mechanisms may help accelerate the discovery of novel drugs that tap the therapeutic potential of microglia.
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Affiliation(s)
- Huan Liu
- Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Xiaoming Hu
- Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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14
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Wendt S, Wogram E, Korvers L, Kettenmann H. Experimental Cortical Spreading Depression Induces NMDA Receptor Dependent Potassium Currents in Microglia. J Neurosci 2016; 36:6165-74. [PMID: 27277795 PMCID: PMC6604883 DOI: 10.1523/jneurosci.4498-15.2016] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 03/10/2016] [Accepted: 04/06/2016] [Indexed: 12/13/2022] Open
Abstract
UNLABELLED Cortical spreading depression (CSD) is a propagating event of neuronal depolarization, which is considered as the cellular correlate of the migraine aura. It is characterized by a change in the intrinsic optical signal and by a negative DC potential shift. Microglia are the resident macrophages of the CNS and act as sensors for pathological changes. In the present study, we analyzed whether microglial cells might sense CSD by recording membrane currents from microglia in acutely isolated cortical mouse brain slices during an experimentally induced CSD. Coincident with the change in the intrinsic optical signal and the negative DC potential shift we recorded an increase in potassium conductance predominantly mediated by K(+) inward rectifier (Kir)2.1, which was blocked by the NMDA receptor antagonist D-AP5. Application of NMDA and an increase in extracellular K(+) mimics the CSD-induced Kir activation. Application of D-AP5, but not the purinergic receptor antagonist RB2, blocks the NMDA-induced Kir activation. The K(+) channel blocker Ba(2+) blocks both the CSD- and the NMDA-triggered increase in Kir channel activity. In addition, we could confirm previous findings that microglia in the adult brain do not express functional NMDA receptors by recording from microglia cultured from adult brain. From these observations we conclude that CSD activates neuronal NMDA receptors, which lead to an increase in extracellular [K(+)] resulting in the activation of Kir channel activity in microglia. SIGNIFICANCE STATEMENT Cortical spreading depression (CSD) is a wave of neuronal depolarization spreading through the cortex and is associated with the aura of migraine. Here we show that microglial cells, which are viewed as pathologic sensors of the brain, can sense this wave. The increase in the extracellular potassium concentration associated with that wave leads to the activation of an inward rectifying potassium conductance in microglia. The involvement of neuronal NMDA receptors is crucial because NMDA mimics that response and microglia do not express functional NMDA receptors. Although it is now evident that CSD leads to a signal in microglia, the consequences of this microglial activation during CSD needs to be explored.
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Affiliation(s)
- Stefan Wendt
- Cellular Neurosciences, Max-Delbrück-Center for Molecular Medicine, 13092 Berlin, Germany, and
| | - Emile Wogram
- Cellular Neurosciences, Max-Delbrück-Center for Molecular Medicine, 13092 Berlin, Germany, and Institute of Physiology and Pathophysiology, University of Heidelberg, 69120 Heidelberg, Germany
| | - Laura Korvers
- Cellular Neurosciences, Max-Delbrück-Center for Molecular Medicine, 13092 Berlin, Germany, and
| | - Helmut Kettenmann
- Cellular Neurosciences, Max-Delbrück-Center for Molecular Medicine, 13092 Berlin, Germany, and
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15
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Wogram E, Wendt S, Matyash M, Pivneva T, Draguhn A, Kettenmann H. Satellite microglia show spontaneous electrical activity that is uncorrelated with activity of the attached neuron. Eur J Neurosci 2016; 43:1523-34. [DOI: 10.1111/ejn.13256] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 03/15/2016] [Accepted: 04/05/2016] [Indexed: 01/25/2023]
Affiliation(s)
- Emile Wogram
- Cellular Neurosciences; Max-Delbrück-Center for Molecular Medicine in the Helmholtz Society; Robert-Rössle-Str. 10 13125 Berlin Germany
- Institute of Physiology and Pathophysiology; University of Heidelberg; Heidelberg Germany
| | - Stefan Wendt
- Cellular Neurosciences; Max-Delbrück-Center for Molecular Medicine in the Helmholtz Society; Robert-Rössle-Str. 10 13125 Berlin Germany
| | - Marina Matyash
- Cellular Neurosciences; Max-Delbrück-Center for Molecular Medicine in the Helmholtz Society; Robert-Rössle-Str. 10 13125 Berlin Germany
| | - Tatyana Pivneva
- General Physiology of Nervous System Department; Bogomoletz Institute of Physiology; Kiev Ukraine
| | - Andreas Draguhn
- Institute of Physiology and Pathophysiology; University of Heidelberg; Heidelberg Germany
| | - Helmut Kettenmann
- Cellular Neurosciences; Max-Delbrück-Center for Molecular Medicine in the Helmholtz Society; Robert-Rössle-Str. 10 13125 Berlin Germany
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16
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Abstract
Neuroglia, the "glue" that fills the space between neurons in the central nervous system, takes active part in nerve cell signaling. Neuroglial cells, astroglia, oligodendroglia, and microglia, are together about as numerous as neurons in the brain as a whole, and in the cerebral cortex grey matter, but the proportion varies widely among brain regions. Glial volume, however, is less than one-fifth of the tissue volume in grey matter. When stimulated by neurons or other cells, neuroglial cells release gliotransmitters by exocytosis, similar to neurotransmitter release from nerve endings, or by carrier-mediated transport or channel flux through the plasma membrane. Gliotransmitters include the common neurotransmitters glutamate and GABA, the nonstandard amino acid d-serine, the high-energy phosphate ATP, and l-lactate. The latter molecule is a "buffer" between glycolytic and oxidative metabolism as well as a signaling substance recently shown to act on specific lactate receptors in the brain. Complementing neurotransmission at a synapse, neuroglial transmission often implies diffusion of the transmitter over a longer distance and concurs with the concept of volume transmission. Transmission from glia modulates synaptic neurotransmission based on energetic and other local conditions in a volume of tissue surrounding the individual synapse. Neuroglial transmission appears to contribute significantly to brain functions such as memory, as well as to prevalent neuropathologies.
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Affiliation(s)
- Vidar Gundersen
- SN-Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, and CMBN/SERTA/Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway; Department of Neurology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; and Brain and Muscle Energy Group, Department of Oral Biology and Division of Anatomy, Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Jon Storm-Mathisen
- SN-Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, and CMBN/SERTA/Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway; Department of Neurology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; and Brain and Muscle Energy Group, Department of Oral Biology and Division of Anatomy, Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Linda Hildegard Bergersen
- SN-Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, and CMBN/SERTA/Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway; Department of Neurology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; and Brain and Muscle Energy Group, Department of Oral Biology and Division of Anatomy, Department of Molecular Medicine, University of Oslo, Oslo, Norway
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17
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Barragan A, Weidner JM, Jin Z, Korpi ER, Birnir B. GABAergic signalling in the immune system. Acta Physiol (Oxf) 2015; 213:819-27. [PMID: 25677654 DOI: 10.1111/apha.12467] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 12/12/2014] [Accepted: 02/06/2015] [Indexed: 01/12/2023]
Abstract
The GABAergic system is the main inhibitory neurotransmitter system in the central nervous system (CNS) of vertebrates. Signalling of the transmitter γ-aminobutyric acid (GABA) via GABA type A receptor channels or G-protein-coupled type B receptors is implicated in multiple CNS functions. Recent findings have implicated the GABAergic system in immune cell functions, inflammatory conditions and diseases in peripheral tissues. Interestingly, the specific effects may vary between immune cell types, with stage of activation and be altered by infectious agents. GABA/GABA-A receptor-mediated immunomodulatory functions have been unveiled in immune cells, being present in T lymphocytes and regulating the migration of Toxoplasma-infected dendritic cells. The GABAergic system may also play a role in the regulation of brain resident immune cells, the microglial cells. Activation of microglia appears to regulate the function of GABAergic neurotransmission in neighbouring neurones through changes induced by secretion of brain-derived neurotrophic factor. The neurotransmitter-driven immunomodulation is a new but rapidly growing field of science. Herein, we review the present knowledge of the GABA signalling in immune cells of the periphery and the CNS and raise questions for future research.
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Affiliation(s)
- A. Barragan
- Department of Molecular Biosciences; The Wenner-Gren Institute; Stockholm University; Stockholm Sweden
- Department of Medicine; Center for Infectious Medicine; Karolinska Institutet; Stockholm Sweden
| | - J. M. Weidner
- Department of Molecular Biosciences; The Wenner-Gren Institute; Stockholm University; Stockholm Sweden
- Department of Medicine; Center for Infectious Medicine; Karolinska Institutet; Stockholm Sweden
| | - Z. Jin
- Department of Neuroscience; Uppsala University; Uppsala Sweden
| | - E. R. Korpi
- Department of Pharmacology; Faculty of Medicine; University of Helsinki; Helsinki Finland
- Department of Pharmacology; Yong Loo Lin School of Medicine; National University Health System; Neurobiology and Ageing Programme; Life Sciences Institute; National University of Singapore, and SINAPSE, Singapore Institute for Neurotechnology; Singapore
| | - B. Birnir
- Department of Neuroscience; Uppsala University; Uppsala Sweden
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18
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Li Q, Lu J, Wang X. Propofol and remifentanil at moderate and high concentrations affect proliferation and differentiation of neural stem/progenitor cells. Neural Regen Res 2015; 9:2002-7. [PMID: 25598783 PMCID: PMC4283284 DOI: 10.4103/1673-5374.145384] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/11/2014] [Indexed: 12/27/2022] Open
Abstract
Propofol and remifentanil alter intracellular Ca2+ concentration ([Ca2+]i) in neural stem/progenitor cells by activating γ-aminobutyric acid type A receptors and by reducing testosterone levels. However, whether this process affects neural stem/progenitor cell proliferation and differentiation remains unknown. In the present study, we applied propofol and remifentanil, alone or in combination, at low, moderate or high concentrations (1, 2–2.5 and 4–5 times the clinically effective blood drug concentration), to neural stem/progenitor cells from the hippocampi of newborn rat pups. Low concentrations of propofol, remifentanil or both had no noticeable effect on cell proliferation or differentiation; however, moderate and high concentrations of propofol and/or remifentanil markedly suppressed neural stem/progenitor cell proliferation and differentiation, and induced a decrease in [Ca2+]i during the initial stage of neural stem/progenitor cell differentiation. We therefore propose that propofol and remifentanil interfere with the proliferation and differentiation of neural stem/progenitor cells by altering [Ca2+]i. Our findings suggest that propofol and/or remifentanil should be used with caution in pediatric anesthesia.
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Affiliation(s)
- Qing Li
- Department of Anesthesiology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei Province, China ; Anesthesiology Research Institude, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei Province, China
| | - Jiang Lu
- Department of Anesthesiology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei Province, China ; Anesthesiology Research Institude, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei Province, China
| | - Xianyu Wang
- Department of Anesthesiology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei Province, China ; Anesthesiology Research Institude, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei Province, China
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Ziemlińska E, Kügler S, Schachner M, Wewiór I, Czarkowska-Bauch J, Skup M. Overexpression of BDNF increases excitability of the lumbar spinal network and leads to robust early locomotor recovery in completely spinalized rats. PLoS One 2014; 9:e88833. [PMID: 24551172 PMCID: PMC3925164 DOI: 10.1371/journal.pone.0088833] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 01/16/2014] [Indexed: 02/05/2023] Open
Abstract
Strategies to induce recovery from lesions of the spinal cord have not fully resulted in clinical applications. This is a consequence of a number of impediments that axons encounter when trying to regrow beyond the lesion site, and that intraspinal rearrangements are subjected to. In the present study we evaluated (1) the possibility to improve locomotor recovery after complete transection of the spinal cord by means of an adeno-associated (AAV) viral vector expressing the neurotrophin brain-derived neurotrophic factor (BDNF) in lumbar spinal neurons caudal to the lesion site and (2) how the spinal cord transection and BDNF treatment affected neurotransmission in the segments caudal to the lesion site. BDNF overexpression resulted in clear increases in expression levels of molecules involved in glutamatergic (VGluT2) and GABAergic (GABA, GAD65, GAD67) neurotransmission in parallel with a reduction of the potassium-chloride co-transporter (KCC2) which contributes to an inhibitory neurotransmission. BDNF treated animals showed significant improvements in assisted locomotor performance, and performed locomotor movements with body weight support and plantar foot placement on a moving treadmill. These positive effects of BDNF local overexpression were detectable as early as two weeks after spinal cord transection and viral vector application and lasted for at least 7 weeks. Gradually increasing frequencies of clonic movements at the end of the experiment attenuated the quality of treadmill walking. These data indicate that BDNF has the potential to enhance the functionality of isolated lumbar circuits, but also that BDNF levels have to be tightly controlled to prevent hyperexcitability.
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Affiliation(s)
| | - Sebastian Kügler
- Center of Molecular Physiology of the Brain, University of Göttingen, Göttingen, Germany
| | - Melitta Schachner
- Center for Neuroscience, Shantou University Medical College, Shantou, China
| | - Iwona Wewiór
- Nencki Institute of Experimental Biology, Warsaw, Poland
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20
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Zhu XB, Wang YB, Chen O, Zhang DQ, Zhang ZH, Cao AH, Huang SY, Sun RP. Characterization of the expression of macrophage inflammatory protein-1α (MIP-1α) and C-C chemokine receptor 5 (CCR5) after kainic acid-induced status epilepticus (SE) in juvenile rats. Neuropathol Appl Neurobiol 2012; 38:602-16. [DOI: 10.1111/j.1365-2990.2012.01251.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Mead EL, Mosley A, Eaton S, Dobson L, Heales SJ, Pocock JM. Microglial neurotransmitter receptors trigger superoxide production in microglia; consequences for microglial-neuronal interactions. J Neurochem 2012; 121:287-301. [DOI: 10.1111/j.1471-4159.2012.07659.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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22
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Regulation of microglia by ionotropic glutamatergic and GABAergic neurotransmission. ACTA ACUST UNITED AC 2011; 7:41-6. [PMID: 22166726 DOI: 10.1017/s1740925x11000123] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Recent studies have indicated that constitutive functions of microglia in the healthy adult central nervous system (CNS) involve immune surveillance, synapse maintenance and trophic support. These functions have been related to the ramified structure of 'resting' microglia and the prominent motility in their processes that provide extensive coverage of the entire extracellular milleu. In this review, we examine how external signals, and in particular, ionotropic neurotransmission, regulate features of microglial morphology and process motility. Current findings indicate that microglial physiology in the healthy CNS is constitutively and reciprocally regulated by endogenous ionotropic glutamatergic and GABAergic neurotransmission. These influences do not act directly on microglial cells but indirectly via the activity-dependent release of ATP, likely through a mechanism involving pannexin channels. Microglia in the 'resting' state are not only dynamically active, but also constantly engaged in ongoing communication with neuronal and macroglial components of the CNS in a functionally relevant way.
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23
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Levesque S, Surace MJ, McDonald J, Block ML. Air pollution & the brain: Subchronic diesel exhaust exposure causes neuroinflammation and elevates early markers of neurodegenerative disease. J Neuroinflammation 2011; 8:105. [PMID: 21864400 PMCID: PMC3184279 DOI: 10.1186/1742-2094-8-105] [Citation(s) in RCA: 229] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 08/24/2011] [Indexed: 12/21/2022] Open
Abstract
Background Increasing evidence links diverse forms of air pollution to neuroinflammation and neuropathology in both human and animal models, but the effects of long-term exposures are poorly understood. Objective We explored the central nervous system consequences of subchronic exposure to diesel exhaust (DE) and addressed the minimum levels necessary to elicit neuroinflammation and markers of early neuropathology. Methods Male Fischer 344 rats were exposed to DE (992, 311, 100, 35 and 0 μg PM/m3) by inhalation over 6 months. Results DE exposure resulted in elevated levels of TNFα at high concentrations in all regions tested, with the exception of the cerebellum. The midbrain region was the most sensitive, where exposures as low as 100 μg PM/m3 significantly increased brain TNFα levels. However, this sensitivity to DE was not conferred to all markers of neuroinflammation, as the midbrain showed no increase in IL-6 expression at any concentration tested, an increase in IL-1β at only high concentrations, and a decrease in MIP-1α expression, supporting that compensatory mechanisms may occur with subchronic exposure. Aβ42 levels were the highest in the frontal lobe of mice exposed to 992 μg PM/m3 and tau [pS199] levels were elevated at the higher DE concentrations (992 and 311 μg PM/m3) in both the temporal lobe and frontal lobe, indicating that proteins linked to preclinical Alzheimer's disease were affected. α Synuclein levels were elevated in the midbrain in response to the 992 μg PM/m3 exposure, supporting that air pollution may be associated with early Parkinson's disease-like pathology. Conclusions Together, the data support that the midbrain may be more sensitive to the neuroinflammatory effects of subchronic air pollution exposure. However, the DE-induced elevation of proteins associated with neurodegenerative diseases was limited to only the higher exposures, suggesting that air pollution-induced neuroinflammation may precede preclinical markers of neurodegenerative disease in the midbrain.
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Affiliation(s)
- Shannon Levesque
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Campus, Richmond, VA 23298, USA
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24
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Abstract
Microglial cells are the resident macrophages in the central nervous system. These cells of mesodermal/mesenchymal origin migrate into all regions of the central nervous system, disseminate through the brain parenchyma, and acquire a specific ramified morphological phenotype termed "resting microglia." Recent studies indicate that even in the normal brain, microglia have highly motile processes by which they scan their territorial domains. By a large number of signaling pathways they can communicate with macroglial cells and neurons and with cells of the immune system. Likewise, microglial cells express receptors classically described for brain-specific communication such as neurotransmitter receptors and those first discovered as immune cell-specific such as for cytokines. Microglial cells are considered the most susceptible sensors of brain pathology. Upon any detection of signs for brain lesions or nervous system dysfunction, microglial cells undergo a complex, multistage activation process that converts them into the "activated microglial cell." This cell form has the capacity to release a large number of substances that can act detrimental or beneficial for the surrounding cells. Activated microglial cells can migrate to the site of injury, proliferate, and phagocytose cells and cellular compartments.
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25
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Vélez-Fort M, Audinat E, Angulo MC. Central Role of GABA in Neuron–Glia Interactions. Neuroscientist 2011; 18:237-50. [PMID: 21609943 DOI: 10.1177/1073858411403317] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The major types of glial cells—astrocytes, microglia, and cells of the oligodendroglial lineage—are known to express functional metabotropic and ionotropic GABA receptors. Neuronal signaling mechanisms allowing for the activation of these receptors in glia are probably as complex as those described among neurons and involve synaptic and extrasynaptic transmission modes. In addition, astrocytes can signal back to neurons by releasing GABA, probably through unconventional nonvesicular mechanisms. The decryption of the roles played by GABAergic signaling in neuron–glia interactions is only beginning, but it has been suggested that activation of glial cells by GABA influences important functions of the brain such as neuronal activity, differentiation, myelination, and neuroprotection. This review discusses the cellular mechanisms allowing the major types of glial cells to sense and transmit GABAergic signals and gives an overview of potential roles of this signaling pathway in developing and mature brains.
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Affiliation(s)
- Mateo Vélez-Fort
- Inserm U603, Paris, France
- CNRS UMR 8154, Paris, France
- Université Paris Descartes, Paris, France
- Division of Neurophysiology, The National Institute for Medical Research, Mill Hill, UK
| | - Etienne Audinat
- Inserm U603, Paris, France
- CNRS UMR 8154, Paris, France
- Université Paris Descartes, Paris, France
| | - María Cecilia Angulo
- Inserm U603, Paris, France
- CNRS UMR 8154, Paris, France
- Université Paris Descartes, Paris, France
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26
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Possible role of propofol's cyclooxygenase-inhibiting property in alleviating dopaminergic neuronal loss in the substantia nigra in an MPTP-induced murine model of Parkinson's disease. Brain Res 2011; 1387:125-33. [PMID: 21376018 DOI: 10.1016/j.brainres.2011.02.079] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Revised: 02/24/2011] [Accepted: 02/24/2011] [Indexed: 12/17/2022]
Abstract
Propofol is an intravenous anesthetic widely used for sedation and general anesthesia. We investigated the effect of propofol on prostanoid production by activated microglia. Primary microglial culture was obtained from the brains of neonatal C57BL/6 mice. The microglia were stimulated with lipopolysaccharide (LPS) in the presence of propofol. Propofol suppressed the LPS-induced production of prostaglandin E(2) and thromboxane B(2). Cyclooxygenase (COX) protein expression and arachidonic acid release were not affected by propofol, while COX enzyme activity was significantly inhibited by propofol. The COX-inhibiting activity was also observed with purified enzymes, with COX-2 inhibition being significantly greater than COX-1 inhibition. Next, we studied whether the COX-inhibiting activity of propofol resulted in dopaminergic neuroprotection in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) murine model of Parkinson's disease, in which COX inhibitors, such as non-steroidal anti-inflammatory drugs, are reported to be neuroprotective. C57BL/6 mice received intraperitoneal injections of MPTP with or without propofol treatment, and the dopaminergic neurons in the substantia nigra pars compacta (SNpc) were examined immunohistochemically by observing the tyrosine hydroxylase-positive cells. The number of dopaminergic neurons in the SNpc was significantly reduced by MPTP treatment, while the MPTP-induced neuronal loss was minimal upon treatment with propofol or the selective COX-2 inhibitor, NS-398. These results indicate that propofol might be beneficial in mitigating MPTP-induced dopaminergic neurons, possibly via its COX-inhibiting activity.
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Lee M, Schwab C, McGeer PL. Astrocytes are GABAergic cells that modulate microglial activity. Glia 2011; 59:152-65. [PMID: 21046567 DOI: 10.1002/glia.21087] [Citation(s) in RCA: 228] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
GABA is assumed to function in brain only as an inhibitory neurotransmitter. Here we report a much broader CNS role. We show that human astrocytes are GABAergic cells, and that human microglia are GABAceptive cells. We show that in adult human brain tissue, astrocytes immunostain for the GABA synthesizing enzyme GAD 67, the GABA metabolizing enzyme GABA-T and the GABA(A) and GABA(B) receptors. The intensity of staining is comparable or greater to that observed for known inhibitory neurons. We show that cultured human astrocytes strongly express the mRNA and protein for GAD 67, as well as GABA-T, and the GABA(A) and GABA(B) receptors. We further show that cultured human microglia express the mRNA and protein for GABA-T, in addition to the GABA(A) and GABA(B) receptors characterizing them as GABAceptive cells. We demonstrate that GABA suppresses the reactive response of both astrocytes and microglia to the inflammatory stimulants lipopolysaccharide (LPS) and interferon-γ by inhibiting induction of inflammatory pathways mediated by NFκB and P38 MAP kinase. This results in a reduced release of the inflammatory cytokines TNFα and IL-6 and an attenuation of conditioned medium neurotoxicity toward neuroblastoma SH-SY5Y cells. These inhibitory reactions are partially mimicked by the GABA(A) receptor agonist muscimol and the GABA(B) receptor agonist baclofen, indicating that GABA can stimulate both types of receptors in astrocytes as well as microglia. We conclude that the antiinflammatory actions of GABA offer new therapeutic opportunities since agonists should enhance the effectiveness of other antiinflammatory agents that operate through non-GABA pathways.
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Affiliation(s)
- Moonhee Lee
- Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, BC, Canada
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Koelsch A, Feng Y, Fink DJ, Mata M. Transgene-mediated GDNF expression enhances synaptic connectivity and GABA transmission to improve functional outcome after spinal cord contusion. J Neurochem 2010; 113:143-52. [PMID: 20132484 DOI: 10.1111/j.1471-4159.2010.06593.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glial cell line-derived trophic factor (GDNF) is a peptide with pleiotropic survival and growth-promoting effects on neurons. We found that intraspinal injection of a non-replicating herpes simplex virus-based vector coding for GDNF 2 h after blunt trauma to the thoraco-lumbar spinal cord produced sustained improvement in motor behavioral outcomes up to 5 weeks following injury. The improvement in behavior correlated with an increase in synaptophysin and glutamic acid decarboxylase (GAD) in the spinal cord at the level of injury. Addition of recombinant GDNF protein to primary spinal cord neurons in-vitro resulted in enhanced neurite growth and a marked increase in protein levels of GAD65 and GAD67, synapsin I and synaptophysin. GDNF-mediated increases in GAD and the synaptic markers were blocked by the MEK inhibitor UO126, but not by the phosphoinositide 3-kinase inhibitor LY294002. These results suggest that GDNF, acting through the MEK-ERK pathway enhances axonal sprouting, synaptic connectivity, and GABAergic neurotransmission in the spinal cord, that result in improved behavioral outcomes after spinal cord contusion injury.
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Affiliation(s)
- Angela Koelsch
- Department of Neurology, University of Michigan and Ann Arbor VA Healthcare System, Ann Arbor, MI, USA
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