1
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Moreno-Jiménez EP, Flor-García M, Hernández-Vivanco A, Terreros-Roncal J, Rodríguez-Moreno CB, Toni N, Méndez P, Llorens-Martín M. GSK-3β orchestrates the inhibitory innervation of adult-born dentate granule cells in vivo. Cell Mol Life Sci 2023; 80:225. [PMID: 37481766 PMCID: PMC10363517 DOI: 10.1007/s00018-023-04874-w] [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: 04/27/2023] [Revised: 06/30/2023] [Accepted: 07/12/2023] [Indexed: 07/25/2023]
Abstract
Adult hippocampal neurogenesis enhances brain plasticity and contributes to the cognitive reserve during aging. Adult hippocampal neurogenesis is impaired in neurological disorders, yet the molecular mechanisms regulating the maturation and synaptic integration of new neurons have not been fully elucidated. GABA is a master regulator of adult and developmental neurogenesis. Here we engineered a novel retrovirus encoding the fusion protein Gephyrin:GFP to longitudinally study the formation and maturation of inhibitory synapses during adult hippocampal neurogenesis in vivo. Our data reveal the early assembly of inhibitory postsynaptic densities at 1 week of cell age. Glycogen synthase kinase 3 Beta (GSK-3β) emerges as a key regulator of inhibitory synapse formation and maturation during adult hippocampal neurogenesis. GSK-3β-overexpressing newborn neurons show an increased number and altered size of Gephyrin+ postsynaptic clusters, enhanced miniature inhibitory postsynaptic currents, shorter and distanced axon initial segments, reduced synaptic output at the CA3 and CA2 hippocampal regions, and impaired pattern separation. Moreover, GSK-3β overexpression triggers a depletion of Parvalbumin+ interneuron perineuronal nets. These alterations might be relevant in the context of neurological diseases in which the activity of GSK-3β is dysregulated.
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Affiliation(s)
- E P Moreno-Jiménez
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa (CBMSO), Spanish Research Council (CSIC), Universidad Autónoma de Madrid (UAM) (Campus de Cantoblanco), c/Nicolás Cabrera 1, 28049, Madrid, Spain
- Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
- Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain
| | - M Flor-García
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa (CBMSO), Spanish Research Council (CSIC), Universidad Autónoma de Madrid (UAM) (Campus de Cantoblanco), c/Nicolás Cabrera 1, 28049, Madrid, Spain
- Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
- Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain
| | | | - J Terreros-Roncal
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa (CBMSO), Spanish Research Council (CSIC), Universidad Autónoma de Madrid (UAM) (Campus de Cantoblanco), c/Nicolás Cabrera 1, 28049, Madrid, Spain
- Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
- Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain
| | - C B Rodríguez-Moreno
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa (CBMSO), Spanish Research Council (CSIC), Universidad Autónoma de Madrid (UAM) (Campus de Cantoblanco), c/Nicolás Cabrera 1, 28049, Madrid, Spain
- Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
- Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain
| | - N Toni
- Department of Psychiatry, Center for Psychiatric Neurosciences, , Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - P Méndez
- Cajal Institute, CSIC, Madrid, Spain
| | - María Llorens-Martín
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa (CBMSO), Spanish Research Council (CSIC), Universidad Autónoma de Madrid (UAM) (Campus de Cantoblanco), c/Nicolás Cabrera 1, 28049, Madrid, Spain.
- Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain.
- Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain.
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2
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Evidences for Adult Hippocampal Neurogenesis in Humans. J Neurosci 2021; 41:2541-2553. [PMID: 33762406 DOI: 10.1523/jneurosci.0675-20.2020] [Citation(s) in RCA: 105] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 07/20/2020] [Accepted: 09/28/2020] [Indexed: 12/16/2022] Open
Abstract
The rodent hippocampus generates new neurons throughout life. This process, named adult hippocampal neurogenesis (AHN), is a striking form of neural plasticity that occurs in the brains of numerous mammalian species. Direct evidence of adult neurogenesis in humans has remained elusive, although the occurrence of this phenomenon in the human dentate gyrus has been demonstrated in seminal studies and recent research that have applied distinct approaches to birthdate newly generated neurons and to validate markers of adult-born neurons. Our data point to the persistence of AHN until the 10th decade of human life, as well as to marked impairments in this process in patients with Alzheimer's disease. Moreover, our work demonstrates that the methods used to process and analyze postmortem human brain samples can limit the detection of various markers of AHN to the point of making them undetectable. In this Dual Perspectives article, we highlight the critical methodological aspects that should be strictly controlled in human studies and the robust evidence that supports the occurrence of AHN in humans. We also put forward reasons that may account for current discrepancies on this topic. Finally, the unresolved questions and future challenges awaiting the field are highlighted.
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3
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Unraveling human adult hippocampal neurogenesis. Nat Protoc 2020; 15:668-693. [PMID: 31915385 DOI: 10.1038/s41596-019-0267-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Accepted: 10/30/2019] [Indexed: 01/27/2023]
Abstract
Adult neurogenesis occurs in a few selected regions of the mammalian brain. One such region is the hippocampus, the so-called gateway to memory, where adult hippocampal neurogenesis (AHN) occurs. Here, we provide a comprehensive description of the methods used in our laboratory to unambiguously detect a population of immature neurons in the human hippocampus until the 10th decade of life. The criteria used to refine and develop the current protocol include obtaining post-mortem human samples of remarkable quality and under tightly controlled conditions for immunohistochemistry (IHC) studies, optimizing tissue processing and histological procedures, establishing criteria to reliably validate antibody signal and performing unbiased stereological cell counts. Moreover, we provide a detailed description of the parameters that, in our view, should be reported in human AHN studies. The opposing results obtained by introducing slight variations in the methodological conditions should be considered by future studies that seek to increase our knowledge of this fascinating process. By applying simple and inexpensive tissue pre-treatments, this protocol, which can be completed in 7 days, might be applicable to a variety of IHC studies performed on other tissues of human (or animal) origin.
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4
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Teixeira CM, Pallas-Bazarra N, Bolós M, Terreros-Roncal J, Ávila J, Llorens-Martín M. Untold New Beginnings: Adult Hippocampal Neurogenesis and Alzheimer's Disease. J Alzheimers Dis 2019; 64:S497-S505. [PMID: 29562522 DOI: 10.3233/jad-179918] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Neurogenesis occurs in a limited number of brain regions during adulthood. Of these, the hippocampus has attracted great interest due to its involvement in memory processing. Moreover, both the hippocampus and the main area that innervates this structure, namely the entorhinal cortex, show remarkable atrophy in patients with Alzheimer's disease (AD). Adult hippocampal neurogenesis is a process that continuously gives rise to newborn granule neurons in the dentate gyrus. These cells coexist with developmentally generated granule neurons in this structure, and both cooperative and competition phenomena regulate the communication between these two types of cells. Importantly, it has been revealed that GSK-3β and tau proteins, which are two of the main players driving AD pathology, are cornerstones of adult hippocampal neurogenesis regulation. We have shown that alterations either promoting or impeding the actions of these two proteins have detrimental effects on the structural plasticity of granule neurons. Of note, these impairments occur both under basal conditions and in response to detrimental and neuroprotective stimuli. Thus, in order to achieve the full effectiveness of future therapies for AD, we propose that attention be turned toward identifying the pathological and physiological actions of the proteins involved in the pathogenesis of this condition.
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Affiliation(s)
- Catia M Teixeira
- Emotional Brain Institute, Nathan Kline Institute, New York, NY, USA
| | - Noemí Pallas-Bazarra
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa", CBMSO, CSIC-UAM, Madrid, Spain.,Center for Networked Biomedical Research on neurodegenerative diseases (CIBERNED), Madrid, Spain
| | - Marta Bolós
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa", CBMSO, CSIC-UAM, Madrid, Spain.,Center for Networked Biomedical Research on neurodegenerative diseases (CIBERNED), Madrid, Spain
| | - Julia Terreros-Roncal
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa", CBMSO, CSIC-UAM, Madrid, Spain.,Center for Networked Biomedical Research on neurodegenerative diseases (CIBERNED), Madrid, Spain
| | - Jesús Ávila
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa", CBMSO, CSIC-UAM, Madrid, Spain.,Center for Networked Biomedical Research on neurodegenerative diseases (CIBERNED), Madrid, Spain
| | - María Llorens-Martín
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa", CBMSO, CSIC-UAM, Madrid, Spain.,Center for Networked Biomedical Research on neurodegenerative diseases (CIBERNED), Madrid, Spain.,Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain
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5
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Adult hippocampal neurogenesis is abundant in neurologically healthy subjects and drops sharply in patients with Alzheimer’s disease. Nat Med 2019; 25:554-560. [DOI: 10.1038/s41591-019-0375-9] [Citation(s) in RCA: 768] [Impact Index Per Article: 153.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/24/2019] [Indexed: 12/17/2022]
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6
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A Network Model Reveals That the Experimentally Observed Switch of the Granule Cell Phenotype During Epilepsy Can Maintain the Pattern Separation Function of the Dentate Gyrus. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/978-3-319-99103-0_23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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7
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Llorens-Martín M. Exercising New Neurons to Vanquish Alzheimer Disease. Brain Plast 2018; 4:111-126. [PMID: 30564550 PMCID: PMC6296267 DOI: 10.3233/bpl-180065] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/21/2018] [Indexed: 02/07/2023] Open
Abstract
Alzheimer disease (AD) is the most common type of dementia in individuals over 65 years of age. The neuropathological hallmarks of the condition are Tau neurofibrillary tangles and Amyloid-β senile plaques. Moreover, certain susceptible regions of the brain experience a generalized lack of neural plasticity and marked synaptic alterations during the progression of this as yet incurable disease. One of these regions, the hippocampus, is characterized by the continuous addition of new neurons throughout life. This phenomenon, named adult hippocampal neurogenesis (AHN), provides a potentially endless source of new synaptic elements that increase the complexity and plasticity of the hippocampal circuitry. Numerous lines of evidence show that physical activity and environmental enrichment (EE) are among the most potent positive regulators of AHN. Given that neural plasticity is markedly decreased in many neurodegenerative diseases, the therapeutic potential of making certain lifestyle changes, such as increasing physical activity, is being recognised in several non-pharmacologic strategies seeking to slow down or prevent the progression of these diseases. This review article summarizes current evidence supporting the putative therapeutic potential of EE and physical exercise to increase AHN and hippocampal plasticity both under physiological and pathological circumstances, with a special emphasis on neurodegenerative diseases and AD.
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Affiliation(s)
- María Llorens-Martín
- Department of Molecular Neuropathology, Centro de Biología Molecular “Severo Ochoa”, CBMSO, CSIC-UAM, Madrid, Spain
- Center for Networked Biomedical Research on Neurodegenerative Diseases CIBERNED, Madrid, Spain
- Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain
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8
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Coburn JL, Cole TB, Dao KT, Costa LG. Acute exposure to diesel exhaust impairs adult neurogenesis in mice: prominence in males and protective effect of pioglitazone. Arch Toxicol 2018. [PMID: 29523932 DOI: 10.1007/s00204-018-2180-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Adult neurogenesis is the process by which neural stem cells give rise to new functional neurons in specific regions of the adult brain, a process that occurs throughout life. Significantly, neurodegenerative and psychiatric disorders present suppressed neurogenesis, activated microglia, and neuroinflammation. Traffic-related air pollution has been shown to adversely affect the central nervous system. As the cardinal effects of air pollution exposure are microglial activation, and ensuing oxidative stress and neuroinflammation, we investigated whether acute exposures to diesel exhaust (DE) would inhibit adult neurogenesis in mice. Mice were exposed for 6 h to DE at a PM2.5 concentration of 250-300 μg/m3, followed by assessment of adult neurogenesis in the hippocampal subgranular zone (SGZ), the subventricular zone (SVZ), and olfactory bulb (OB). DE impaired cellular proliferation in the SGZ and SVZ in males, but not females. DE reduced adult neurogenesis, with male mice showing fewer new neurons in the SGZ, SVZ, and OB, and females showing fewer new neurons only in the OB. To assess whether blocking microglial activation protected against DE-induced suppression of adult hippocampal neurogenesis, male mice were pre-treated with pioglitazone (PGZ) prior to DE exposure. The effects of DE exposure on microglia, as well as neuroinflammation and oxidative stress, were reduced by PGZ. PGZ also antagonized DE-induced suppression of neurogenesis in the SGZ. These results suggest that DE exposure impairs adult neurogenesis in a sex-dependent manner, by a mechanism likely to involve microglia activation and neuroinflammation.
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Affiliation(s)
- Jacki L Coburn
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA
| | - Toby B Cole
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA.
- Center on Human Development and Disability, University of Washington, Seattle, WA, USA.
| | - Khoi T Dao
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA
| | - Lucio G Costa
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA.
- Department of Medicine and Surgery, University of Parma, Parma, Italy.
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9
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Bolós M, Pallas-Bazarra N, Terreros-Roncal J, Perea JR, Jurado-Arjona J, Ávila J, Llorens-Martín M. Soluble Tau has devastating effects on the structural plasticity of hippocampal granule neurons. Transl Psychiatry 2017; 7:1267. [PMID: 29217824 PMCID: PMC5802513 DOI: 10.1038/s41398-017-0013-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 07/03/2017] [Accepted: 07/30/2017] [Indexed: 12/26/2022] Open
Abstract
Tau is a neuronal microtubule-associated protein with countless physiological functions. Although the detrimental effects of insoluble aggregated Tau have been widely studied, recent evidence supports the notion that soluble Tau (composed mostly of monomers and dimers) is also toxic for neurons. Here we evaluated the long-term impact of a single stereotaxic injection of human soluble Tau on hippocampal granule neurons in mice. At the ultrastructural level, soluble Tau reduced the number of afferent synapses and caused a dramatic depletion of synaptic vesicles both in afferent and efferent synapses. Furthermore, the use of an RFP-expressing retrovirus revealed that soluble Tau altered the morphology of newborn granule neurons and reduced their afferent (dendritic spines) and efferent (mossy fiber terminals) connectivity. Finally, soluble Tau caused specific impairment of behavioral pattern separation capacity. Our results thus demonstrate for the first time that soluble Tau causes long-term detrimental effects on the morphology and connectivity of newborn granule neurons and that these effects correlate with impaired behavioral pattern separation skills. These data might be relevant for the field of neurodegenerative disorders, since they contribute to reinforcing the pathological roles played by distinct Tau species in vivo.
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Affiliation(s)
- M Bolós
- grid.465524.4Department of Molecular Neuropathology, Centro de Biología Molecular “Severo Ochoa”, CBMSO, CSICUAM, Madrid, Spain ,0000 0004 1762 4012grid.418264.dNetwork Center for Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - N Pallas-Bazarra
- grid.465524.4Department of Molecular Neuropathology, Centro de Biología Molecular “Severo Ochoa”, CBMSO, CSICUAM, Madrid, Spain ,0000 0004 1762 4012grid.418264.dNetwork Center for Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - J Terreros-Roncal
- grid.465524.4Department of Molecular Neuropathology, Centro de Biología Molecular “Severo Ochoa”, CBMSO, CSICUAM, Madrid, Spain ,0000 0004 1762 4012grid.418264.dNetwork Center for Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - JR Perea
- grid.465524.4Department of Molecular Neuropathology, Centro de Biología Molecular “Severo Ochoa”, CBMSO, CSICUAM, Madrid, Spain ,0000 0004 1762 4012grid.418264.dNetwork Center for Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - J Jurado-Arjona
- grid.465524.4Department of Molecular Neuropathology, Centro de Biología Molecular “Severo Ochoa”, CBMSO, CSICUAM, Madrid, Spain ,0000 0004 1762 4012grid.418264.dNetwork Center for Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - J Ávila
- grid.465524.4Department of Molecular Neuropathology, Centro de Biología Molecular “Severo Ochoa”, CBMSO, CSICUAM, Madrid, Spain ,0000 0004 1762 4012grid.418264.dNetwork Center for Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - M Llorens-Martín
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa", CBMSO, CSICUAM, Madrid, Spain. .,Network Center for Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain. .,Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain.
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10
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Nandi S, Alviña K, Lituma PJ, Castillo PE, Hébert JM. Neurotrophin and FGF Signaling Adapter Proteins, FRS2 and FRS3, Regulate Dentate Granule Cell Maturation and Excitatory Synaptogenesis. Neuroscience 2017; 369:192-201. [PMID: 29155277 DOI: 10.1016/j.neuroscience.2017.11.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/07/2017] [Accepted: 11/11/2017] [Indexed: 12/15/2022]
Abstract
Dentate granule cells (DGCs) play important roles in cognitive processes. Knowledge about how growth factors such as FGFs and neurotrophins contribute to the maturation and synaptogenesis of DGCs is limited. Here, using brain-specific and germline mouse mutants we show that a module of neurotrophin and FGF signaling, the FGF Receptor Substrate (FRS) family of intracellular adapters, FRS2 and FRS3, are together required for postnatal brain development. In the hippocampus, FRS promotes dentate gyrus morphogenesis and DGC maturation during developmental neurogenesis, similar to previously published functions for both neurotrophins and FGFs. Consistent with a role in DGC maturation, two-photon imaging revealed that Frs2,3-double mutants have reduced numbers of dendritic branches and spines in DGCs. Functional analysis further showed that double-mutant mice exhibit fewer excitatory synaptic inputs onto DGCs. These observations reveal roles for FRS adapters in DGC maturation and synaptogenesis and suggest that FRS proteins may act as an important node for FGF and neurotrophin signaling in postnatal hippocampal development.
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Affiliation(s)
- Sayan Nandi
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA; Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Karina Alviña
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA; Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
| | - Pablo J Lituma
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Pablo E Castillo
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Jean M Hébert
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA; Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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11
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Li L, Sultan S, Heigele S, Schmidt-Salzmann C, Toni N, Bischofberger J. Silent synapses generate sparse and orthogonal action potential firing in adult-born hippocampal granule cells. eLife 2017; 6:23612. [PMID: 28826488 PMCID: PMC5580881 DOI: 10.7554/elife.23612] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 08/07/2017] [Indexed: 12/12/2022] Open
Abstract
In adult neurogenesis young neurons connect to the existing network via formation of thousands of new synapses. At early developmental stages, glutamatergic synapses are sparse, immature and functionally 'silent', expressing mainly NMDA receptors. Here we show in 2- to 3-week-old young neurons of adult mice, that brief-burst activity in glutamatergic fibers is sufficient to induce postsynaptic AP firing in the absence of AMPA receptors. The enhanced excitability of the young neurons lead to efficient temporal summation of small NMDA currents, dynamic unblocking of silent synapses and NMDA-receptor-dependent AP firing. Therefore, early synaptic inputs are powerfully converted into reliable spiking output. Furthermore, due to high synaptic gain, small dendritic trees and sparse connectivity, neighboring young neurons are activated by different distinct subsets of afferent fibers with minimal overlap. Taken together, synaptic recruitment of young neurons generates sparse and orthogonal AP firing, which may support sparse coding during hippocampal information processing.
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Affiliation(s)
- Liyi Li
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Sébastien Sultan
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Stefanie Heigele
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | | | - Nicolas Toni
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
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12
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Abstract
One of the most hotly pursued topics in neuroscience and therapeutic medicine is the use of stem cells in the adult brain. Growing in parallel to this emerging field is the recognition that the adult brain is indeed capable of generating new cells. While neurogenesis was understood to be restricted to a few areas, recent studies suggest that damage to the adult brain can trigger neurogenesis even in regions outside of these specific areas. This finding raises the possibility that neurons born in response to perturbation in the brain may be involved in the recovery of function in the damaged adult brain. The key is understanding how to cultivate these newborn cells, because they do not remain viable if they are not accepted into the damaged network of interconnected neurons which support specific functions. From a birth site, undifferentiated precursor cells or neurons undergo migration and differentiation. Many factors influence the safe journey of migrating cells and their survival after maturation at their destination. This review will present evidence from ring dove studies that an activity-dependent mechanism underlies the survival of adult newborn neurons and establishment of their functionality. This evidence includes: [1] unique electrophysiological properties or specific connectivity associated with various type of neurons involved in ring dove coo behavior and reproductive function, [2] emergence of electrophysiological properties and specific projection neurons emanating from newborn neurons after hypothalamic lesion, and finally [3] collective behavioral analyses of social stimulations suggesting that sensorimotor events contribute to the integration of new neurons and reinstatement of function.
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Affiliation(s)
- Mei-Fang Cheng
- Department of Psychology, Rutgers, The State University of New Jersey, Newark, NJ, USA
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13
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Pallas-Bazarra N, Kastanauskaite A, Avila J, DeFelipe J, Llorens-Martín M. GSK-3β Overexpression Alters the Dendritic Spines of Developmentally Generated Granule Neurons in the Mouse Hippocampal Dentate Gyrus. Front Neuroanat 2017; 11:18. [PMID: 28344548 PMCID: PMC5344922 DOI: 10.3389/fnana.2017.00018] [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: 02/24/2017] [Indexed: 11/13/2022] Open
Abstract
The dentate gyrus (DG) plays a crucial role in hippocampal-related memory. The most abundant cellular type in the DG, namely granule neurons, are developmentally generated around postnatal day P6 in mice. Moreover, a unique feature of the DG is the occurrence of adult hippocampal neurogenesis, a process that gives rise to newborn granule neurons throughout life. Adult-born and developmentally generated granule neurons share some maturational aspects but differ in others, such as in their positioning within the granule cell layer. Adult hippocampal neurogenesis encompasses a series of plastic changes that modify the function of the hippocampal trisynaptic network. In this regard, it is known that glycogen synthase kinase 3β (GSK-3β) regulates both synaptic plasticity and memory. By using a transgenic mouse overexpressing GSK-3β in hippocampal neurons, we previously demonstrated that the overexpression of this kinase has deleterious effects on the maturation of newborn granule neurons. In the present study, we addressed the effects of GSK-3β overexpression on the morphology and number of dendritic spines of developmentally generated granule neurons. To this end, we performed intracellular injections of Lucifer Yellow in developmentally generated granule neurons of wild-type and GSK-3β-overexpressing mice and analyzed the number and morphologies of dendritic spines (namely, stubby, thin and mushroom). GSK-3β overexpression led to a general reduction in the number of dendritic spines. In addition, it caused a slight reduction in the percentage, head diameter and length of thin spines, whereas the head diameter of mushroom spines was increased.
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Affiliation(s)
- Noemí Pallas-Bazarra
- Centro de Biología Molecular Severo Ochoa - Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de MadridMadrid, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades NeurodegenerativasMadrid, Spain
| | - Asta Kastanauskaite
- Centro de Investigación Biomédica en Red sobre Enfermedades NeurodegenerativasMadrid, Spain; Cajal Laboratory of Cortical Circuits, Centro de Tecnologá Biomédica, Universidad Politécnica de MadridMadrid, Spain
| | - Jesús Avila
- Centro de Biología Molecular Severo Ochoa - Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de MadridMadrid, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades NeurodegenerativasMadrid, Spain
| | - Javier DeFelipe
- Centro de Investigación Biomédica en Red sobre Enfermedades NeurodegenerativasMadrid, Spain; Cajal Laboratory of Cortical Circuits, Centro de Tecnologá Biomédica, Universidad Politécnica de MadridMadrid, Spain; Cajal Institute - Consejo Superior de Investigaciones CientificasMadrid, Spain
| | - María Llorens-Martín
- Centro de Biología Molecular Severo Ochoa - Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de MadridMadrid, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades NeurodegenerativasMadrid, Spain; Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de MadridMadrid, Spain
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14
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Nassan M, Li Q, Croarkin PE, Chen W, Colby CL, Veldic M, McElroy SL, Jenkins GD, Ryu E, Cunningham JM, Leboyer M, Frye MA, Biernacka JM. A genome wide association study suggests the association of muskelin with early onset bipolar disorder: Implications for a GABAergic epileptogenic neurogenesis model. J Affect Disord 2017; 208:120-129. [PMID: 27769005 DOI: 10.1016/j.jad.2016.09.049] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 09/22/2016] [Indexed: 12/28/2022]
Abstract
BACKGROUND Although multiple genes have been implicated in bipolar disorder (BD), they explain only a small proportion of its heritability. Identifying additional BD risk variants may be impaired by phenotypic heterogeneity, which is usually not taken into account in genome-wide association studies (GWAS). BD with early age at onset is a more homogeneous familial form of the disorder associated with greater symptom severity. METHODS We conducted a GWAS of early-onset BD (onset of mania/hypomania ≤19 years old) in a discovery sample of 419 cases and 1034 controls and a replication sample of 181 cases and 777 controls. These two samples were meta-analyzed, followed by replication of one signal in a third independent sample of 141 cases and 746 controls. RESULTS No single nucleotide polymorphism (SNP) associations were genome-wide significant in the discovery sample. Of the top 15 SNPs in the discovery analysis, rs114034759 in the muskelin (MKLN1) gene was nominally significant in the replication analysis, and was among the top associations in the meta-analysis (p=2.63E-06, OR=1.9). In the third sample, this SNP was again associated with early-onset BD (p=0.036, OR=1.6). Gene expression analysis showed that the rs114034759 risk allele is associated with decreased hippocampal MKLN1 expression. LIMITATIONS The sample sizes of the early-onset BD subgroups were relatively small. CONCLUSIONS Our results suggest MKLN1 is associated with early-onset BD. MKLN1 regulates cellular trafficking of GABA-A receptors, which is involved in synaptic transmission and plasticity, and is implicated in the mechanism of action of a group of antiepileptic mood stabilizers. These results therefore indicate that GABAergic neurotransmission may be implicated in early-onset BD. We propose that an increase in GABA-A receptors in the hippocampus in BD patients due to lower MKLN1 expression might increase the excitability during the GABA-excited early phase of young neurons, leading to an increased risk of developing a manic/hypomanic episode. Further studies are needed to test this model.
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Affiliation(s)
- Malik Nassan
- Department of Psychiatry & Psychology, Mayo Clinic Depression Center, Mayo Clinic, Rochester, MN, United States.
| | - Qingqin Li
- Janssen Research & Development, LLC, Titusville, NJ, United States
| | - Paul E Croarkin
- Department of Psychiatry & Psychology, Mayo Clinic Depression Center, Mayo Clinic, Rochester, MN, United States
| | - Wenan Chen
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, United States
| | - Colin L Colby
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, United States
| | - Marin Veldic
- Department of Psychiatry & Psychology, Mayo Clinic Depression Center, Mayo Clinic, Rochester, MN, United States
| | - Susan L McElroy
- Lindner Center of HOPE, Mason, OH and Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, United States
| | - Gregory D Jenkins
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, United States
| | - Euijung Ryu
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, United States
| | - Julie M Cunningham
- Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States
| | - Marion Leboyer
- Université Paris-Est Créteil Val de Marne, Créteil, France
| | - Mark A Frye
- Department of Psychiatry & Psychology, Mayo Clinic Depression Center, Mayo Clinic, Rochester, MN, United States
| | - Joanna M Biernacka
- Department of Psychiatry & Psychology, Mayo Clinic Depression Center, Mayo Clinic, Rochester, MN, United States; Department of Health Sciences Research, Mayo Clinic, Rochester, MN, United States.
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Llorens-Martín M, Teixeira CM, Jurado-Arjona J, Rakwal R, Shibato J, Soya H, Ávila J. Retroviral induction of GSK-3β expression blocks the stimulatory action of physical exercise on the maturation of newborn neurons. Cell Mol Life Sci 2016; 73:3569-82. [PMID: 27010990 PMCID: PMC11108461 DOI: 10.1007/s00018-016-2181-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 03/10/2016] [Accepted: 03/11/2016] [Indexed: 10/22/2022]
Abstract
Adult hippocampal neurogenesis (AHN) is a key process for certain types of hippocampal-dependent learning. Alzheimer's disease (AD) is accompanied by memory deficits related to alterations in AHN. Given that the increased activity of GSK-3β has been related to alterations in the population of hippocampal granule neurons in AD patients, we designed a novel methodology by which to induce selective GSK-3β overexpression exclusively in newborn granule neurons. To this end, we injected an rtTA-IRES-EGFP-expressing retrovirus into the hippocampus of tTO-GSK-3β mice. Using this novel retroviral strategy, we found that GSK-3β caused a cell-autonomous impairment of the morphological and synaptic maturation of newborn neurons. In addition, we examined whether GSK-3β overexpression in newborn neurons limits the effects of physical activity. While physical exercise increased the number of dendritic spines, the percentage of mushroom spines, and the head diameter of the same in tet-OFF cells, these effects were not triggered in tet-ON cells. This observation suggests that GSK-3β blocks the stimulatory actions of exercise. Given that the activity of GSK-3β is increased in the brains of individuals with AD, these data may be relevant for non-pharmacological therapies for AD.
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Affiliation(s)
- María Llorens-Martín
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Universidad Autónoma de Madrid, c/Nicolás Cabrera 1, 28049, Madrid, Spain.
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED, ISCIII), c/Valderrebollo 5, Madrid, Spain.
| | - Catia M Teixeira
- Emotional Brain Institute, Nathan Kline Institute, New York, NY, USA
| | - Jerónimo Jurado-Arjona
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Universidad Autónoma de Madrid, c/Nicolás Cabrera 1, 28049, Madrid, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED, ISCIII), c/Valderrebollo 5, Madrid, Spain
| | - Randeep Rakwal
- Faculty of Health and Sport Sciences and Tsukuba International Academy for Sport Studies (TIAS), University of Tsukuba, Tsukuba, Ibaraki, 305-8574, Japan
- Global Research Center for Innovative Life Science, School of Pharmacy and Pharmaceutical Sciences, Hoshi University, Shinagawa, Tokyo, 142-8501, Japan
| | - Junko Shibato
- Global Research Center for Innovative Life Science, School of Pharmacy and Pharmaceutical Sciences, Hoshi University, Shinagawa, Tokyo, 142-8501, Japan
- Laboratory of Exercise Biochemistry and Neuroendocrinology, Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8574, Japan
| | - Hideaki Soya
- Laboratory of Exercise Biochemistry and Neuroendocrinology, Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8574, Japan
| | - Jesús Ávila
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Universidad Autónoma de Madrid, c/Nicolás Cabrera 1, 28049, Madrid, Spain.
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED, ISCIII), c/Valderrebollo 5, Madrid, Spain.
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16
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Lopez-Rojas J, Kreutz MR. Mature granule cells of the dentate gyrus--Passive bystanders or principal performers in hippocampal function? Neurosci Biobehav Rev 2016; 64:167-74. [PMID: 26949226 DOI: 10.1016/j.neubiorev.2016.02.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Revised: 01/18/2016] [Accepted: 02/27/2016] [Indexed: 10/22/2022]
Abstract
The dentate gyrus is the main entrance of highly processed information to the hippocampus which derives from associative cortices and it is one of the few privileged areas in the brain where adult neurogenesis occurs. This creates the unique situation that neurons of diverse maturation stages are part of one neuronal network at any given point in life. While recently adult-born cells have a low induction threshold for long-term potentiation several studies suggest that following maturation granule cells are poorly excitable and they exhibit reduced Hebbian synaptic plasticity to an extent that it was even suggested that they functionally retire. Here, we review the functional properties of mature granule cells and discuss how plasticity of intrinsic excitability and alterations in excitation-inhibition balance might impact on their role in hippocampal information processing.
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Affiliation(s)
- Jeffrey Lopez-Rojas
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Brenneckestrasse 6, D-39118 Magdeburg, Germany.
| | - Michael R Kreutz
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Brenneckestrasse 6, D-39118 Magdeburg, Germany; Leibniz Group 'Dendritic Organelles and Synaptic Function', University Medical Center Hamburg-Eppendorf, Center for Molecular Neurobiology, ZMNH, 20251 Hamburg, Germany
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17
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Hung HC, Hsiao YH, Gean PW. Sonic hedgehog signaling regulates amygdalar neurogenesis and extinction of fear memory. Eur Neuropsychopharmacol 2015; 25:1723-32. [PMID: 26271722 DOI: 10.1016/j.euroneuro.2015.07.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 06/09/2015] [Accepted: 07/14/2015] [Indexed: 10/23/2022]
Abstract
It is now recognized that neurogenesis occurs throughout life predominantly in the subgranular zone (SGZ) of the hippocampus and the subventricular zone (SVZ) of the lateral ventricle. In the present study, we investigated the relationship between neurogenesis in the amygdala and extinction of fear memory. Mice received 15 tone-footshock pairings. Twenty-four hours after training, the mice were given 15 tone-alone trials (extinction training) once per day for 7 days. Two hours before extinction training, the mice were injected intraperitoneally with 5-bromo-3-deoxyuridine (BrdU). BrdU-positive and NeuN-positive cells were analyzed 52 days after the training. A group of mice that received tone-footshock pairings but no extinction training served as controls (FC+No-Ext). The number of BrdU(+)/NeuN(+) cells was significantly higher in the extinction (FC+Ext) than in the FC+No-Ext mice. Proliferation inhibitor methylazoxymethanol acetate (MAM) or DNA synthesis inhibitor cytosine arabinoside (Ara-C) reduced neurogenesis and retarded extinction. Silencing Sonic hedgehog (Shh) gene with short hairpin interfering RNA (shRNA) by means of a retrovirus expression system to knockdown Shh specifically in the mitotic neurons reduced neurogenesis and retarded extinction. By contrast, over-expression of Shh increased neurogenesis and facilitated extinction. These results suggest that amygdala neurogenesis and Shh signaling are involved in the extinction of fear memory.
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Affiliation(s)
- Hui-Chi Hung
- Institute of Basic Medical Sciences and Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan
| | - Ya-Hsin Hsiao
- Institute of Basic Medical Sciences and Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan
| | - Po-Wu Gean
- Institute of Basic Medical Sciences and Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan.
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18
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SOX11 identified by target gene evaluation of miRNAs differentially expressed in focal and non-focal brain tissue of therapy-resistant epilepsy patients. Neurobiol Dis 2015; 77:127-40. [PMID: 25766675 DOI: 10.1016/j.nbd.2015.02.025] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 01/28/2015] [Accepted: 02/28/2015] [Indexed: 12/31/2022] Open
Abstract
MicroRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally control the expression of their target genes via RNA interference. There is increasing evidence that expression of miRNAs is dysregulated in neuronal disorders, including epilepsy, a chronic neurological disorder characterized by spontaneous recurrent seizures. Mesial temporal lobe epilepsy (MTLE) is a common type of focal epilepsy in which disease-induced abnormalities of hippocampal neurogenesis in the subgranular zone as well as gliosis and neuronal cell loss in the cornu ammonis area are reported. We hypothesized that in MTLE altered miRNA-mediated regulation of target genes could be involved in hippocampal cell remodeling. A miRNA screen was performed in hippocampal focal and non-focal brain tissue samples obtained from the temporal neocortex (both n=8) of MTLE patients. Out of 215 detected miRNAs, two were differentially expressed (hsa-miR-34c-5p: mean increase of 5.7 fold (p=0.014), hsa-miR-212-3p: mean decrease of 76.9% (p=0.0014)). After in-silico target gene analysis and filtering, reporter gene assays confirmed RNA interference for hsa-miR-34c-5p with 3'-UTR sequences of GABRA3, GRM7 and GABBR2 and for hsa-miR-212-3p with 3'-UTR sequences of SOX11, MECP2, ADCY1 and ABCG2. Reporter gene assays with mutated 3'-UTR sequences of the transcription factor SOX11 identified two different binding sites for hsa-miR-212-3p and its primary transcript partner hsa-miR-132-3p. Additionally, there was an inverse time-dependent expression of Sox11 and miR-212-3p as well as miR-132-3p in rat neonatal cortical neurons. Transfection of neurons with anti-miRs for miR-212-3p and miR-132-3p suggest that both miRNAs work synergistically to control Sox11 expression. Taken together, these results suggest that differential miRNA expression in neurons could contribute to an altered function of the transcription factor SOX11 and other genes in the setting of epilepsy, resulting not only in impaired neural differentiation, but also in imbalanced neuronal excitability and accelerated drug export.
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19
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Hung HC, Hsiao YH, Gean PW. Learning induces sonic hedgehog signaling in the amygdala which promotes neurogenesis and long-term memory formation. Int J Neuropsychopharmacol 2015; 18:pyu071. [PMID: 25522410 PMCID: PMC4360236 DOI: 10.1093/ijnp/pyu071] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND It is known that neurogenesis occurs throughout the life mostly in the subgranular zone of the hippocampus and the subventricular zone of the lateral ventricle. We investigated whether neurogenesis occurred in the amygdala and its function in fear memory formation. METHODS For detection of newborn neurons, mice were injected intraperitoneally with 5-bromo-2'-deoxyuridine (BrdU) 2h before receiving 15 tone-footshock pairings, and newborn neurons were analyzed 14 and 42 days after training. To determine the relationship between neurogenesis and memory formation, mice were given a proliferation inhibitor methylazoxymethanol (MAM) or a DNA synthesis inhibitor cytosine arabinoside (Ara-C). To test whether sonic hedgehog (Shh) signaling was required for neurogenesis, Shh-small hairpin-interfering RNA (shRNA) was inserted into a retroviral vector (Retro-Shh-shRNA). RESULTS The number of BrdU(+)/Neuronal nuclei (NeuN)(+) cells was significantly higher in the conditioned mice, suggesting that association of tone with footshock induced neurogenesis. MAM and Ara-C markedly reduced neurogenesis and impaired fear memory formation. Shh, its receptor patched 1 (Ptc1), and transcription factor Gli1 protein levels increased at 1 day and returned to baseline at 7 days after fear conditioning. Retro-Shh-shRNA, which knocked down Shh specifically in the mitotic neurons, reduced the number of BrdU(+)/NeuN(+) cells and decreased freezing responses. CONCLUSIONS These results suggest that fear learning induces Shh signaling activation in the amygdala, which promotes neurogenesis and fear memory formation.
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Affiliation(s)
| | | | - Po-Wu Gean
- Institute of Basic Medical Sciences and Department of Pharmacology, College of Medicine, National Cheng-Kung University, Tainan, Taiwan (Drs Hung, Hsaio, and Gean).
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20
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Llorens-Martín M, Jurado-Arjona J, Avila J, Hernández F. Novel connection between newborn granule neurons and the hippocampal CA2 field. Exp Neurol 2015; 263:285-92. [DOI: 10.1016/j.expneurol.2014.10.021] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Revised: 10/12/2014] [Accepted: 10/23/2014] [Indexed: 12/14/2022]
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Peripherally triggered and GSK-3β-driven brain inflammation differentially skew adult hippocampal neurogenesis, behavioral pattern separation and microglial activation in response to ibuprofen. Transl Psychiatry 2014; 4:e463. [PMID: 25313506 PMCID: PMC4350524 DOI: 10.1038/tp.2014.92] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 07/24/2014] [Accepted: 08/13/2014] [Indexed: 12/14/2022] Open
Abstract
Both familial and sporadic forms of Alzheimer disease (AD) present memory impairments. It has been proposed that these impairments are related to inflammation in relevant brain areas such as the hippocampus. Whether peripherally triggered and neuron-driven brain inflammation produce similar and equally reversible alterations is a matter of discussion. Here we studied the effects of ibuprofen administration on a familial AD mouse model overexpressing GSK-3β that presents severe brain inflammation. We compared these effects with those observed in a peripherally triggered brain inflammation model based on chronic lipopolysaccharide (LPS) administration. Both proinflammatory stimuli produced equivalent reversible morphological alterations in granule neurons; however, GSK-3β had a much more prominent role in newborn neuron connectivity, causing alterations that were not reversed by ibuprofen. Although both insults triggered similar behavioral impairments, ibuprofen rescued this defect in LPS-treated mice but did not produce any improvement in GSK-3β-overexpressing animals. This observation could be attributable to the different microglial phenotype induced by ibuprofen treatment. These data may be clinically relevant for AD therapies, as GSK-3β appears to determine the efficacy of ibuprofen treatment.
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22
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Llorens-Martín M, Jurado J, Hernández F, Avila J. GSK-3β, a pivotal kinase in Alzheimer disease. Front Mol Neurosci 2014; 7:46. [PMID: 24904272 PMCID: PMC4033045 DOI: 10.3389/fnmol.2014.00046] [Citation(s) in RCA: 225] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 05/02/2014] [Indexed: 01/10/2023] Open
Abstract
Alzheimer disease (AD) is the most common form of age-related dementia. The etiology of AD is considered to be multifactorial as only a negligible percentage of cases have a familial or genetic origin. Glycogen synthase kinase-3 (GSK-3) is regarded as a critical molecular link between the two histopathological hallmarks of the disease, namely senile plaques and neurofibrillary tangles. In this review, we summarize current data regarding the involvement of this kinase in several aspects of AD development and progression, as well as key observations highlighting GSK-3 as one of the most relevant targets for AD treatment.
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Affiliation(s)
| | - Jerónimo Jurado
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de Madrid Madrid, Spain ; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Instituto de Salud Carlos III Madrid, Spain
| | - Félix Hernández
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de Madrid Madrid, Spain ; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Instituto de Salud Carlos III Madrid, Spain ; Biology Faculty, Autónoma University Madrid, Spain
| | - Jesús Avila
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de Madrid Madrid, Spain ; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Instituto de Salud Carlos III Madrid, Spain
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23
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Schmidt-Salzmann C, Li L, Bischofberger J. Functional properties of extrasynaptic AMPA and NMDA receptors during postnatal hippocampal neurogenesis. J Physiol 2013; 592:125-40. [PMID: 24218546 DOI: 10.1113/jphysiol.2013.267203] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
In the mammalian hippocampus, new granule cells are continuously generated throughout life. Although it is well known that they rapidly form several thousand new glutamatergic synapses, the underlying mechanisms are not well understood. As extrasynaptic NMDA receptors are believed to support the generation of new spines, we have studied the functional properties of extrasynaptic ionotropic glutamate receptors in newborn granule cells in juvenile rats during and after synaptic integration. Using the fast application of glutamate to outside-out membrane patches, we show that all immature granule cells express functional AMPA and NMDA receptors. The density of AMPA receptors was small in cells starting to receive excitatory synaptic input (∼30 pS μm(-2)) but substantially increased during synaptic integration to finally reach ∼120 pS μm(-2) in fully mature cells. Interestingly, AMPA receptors showed a biphasic change in desensitization time constant which was slowest during synaptic integration and substantially faster before and afterwards. This was paralleled by a change in the non-desensitizing current component which was maximal during synaptic integration and about 50% smaller afterwards. Surprisingly, the NMDA receptor kinetics and density in young cells was already comparable to mature cells (∼10 pS μm(-2)), leading to an enhanced NMDA/AMPA receptor density ratio. Similar to somatic outside-out patches, iontophoretic application of glutamate onto dendrites also revealed an enhanced dendritic NMDA/AMPA ratio in young cells. These data indicate that prolonged AMPA receptor currents in newly generated young granule cells might support the effective activation of extrasynaptic NMDA receptors and therefore constitute a competitive advantage over mature cells for new synapse formation.
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Affiliation(s)
- Charlotte Schmidt-Salzmann
- J. Bischofberger: Department of Biomedicine, Physiological Institute, University of Basel, Pestalozzistr. 20, CH-4056 Basel, Switzerland.
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Weisz VI, Argibay PF. Neurogenesis interferes with the retrieval of remote memories: forgetting in neurocomputational terms. Cognition 2012; 125:13-25. [PMID: 22841299 DOI: 10.1016/j.cognition.2012.07.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 06/22/2012] [Accepted: 07/03/2012] [Indexed: 01/05/2023]
Abstract
In contrast to models and theories that relate adult neurogenesis with the processes of learning and memory, almost no solid hypotheses have been formulated that involve a possible neurocomputational influence of adult neurogenesis on forgetting. Based on data from a previous study that implemented a simple but complete model of the main hippocampal circuitry (Weisz & Argibay, 2009), we now test this model under different situations to better study the case of remote memories. The results of this work show that following neurogenesis, the new, ongoing memories in the hippocampus are better retained than when no neurogenesis occurs at all, while the older memories are affected (to a lesser extent) by a special type of interference that is different from interference that occurs with an increasing number of memories per se. This work adds a new point of analysis in support of the interference view that might lead to the forgetting of memories in the hippocampus as they are transferred to neocortex for long-term storage, consistent with the Complementary Learning Systems models of system-level consolidation. Attention should be directed to the specific causes of interference; the results of this work signal a type of distortion of remote memories that is produced by the birth and the growth of new processing units, which results in a subtly impoverished retrieval as new neurons become active. The proposals of this model fit well with some empirical findings that are related to the issue. In the future, as new evidence emerges, we believe that this biological process, which is largely related to learning and memory, will also help to shape our ideas about normal forgetting and its possible contributions to system consolidation.
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Affiliation(s)
- Victoria I Weisz
- Laboratory for Biological & Artificial Learning, Instituto de Ciencias Básicas y Medicina Experimental, Hospital Italiano de Buenos Aires, Argentina.
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25
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Kim SH. Surgically treatable dementia. JOURNAL OF THE KOREAN MEDICAL ASSOCIATION 2012. [DOI: 10.5124/jkma.2012.55.3.250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Seong Ho Kim
- Department of Neurosurgery, Yeungnam University College of Medicine, Daegu, Korea
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Granulocyte colony-stimulating factor increases the therapeutic efficacy of bone marrow mononuclear cell transplantation in cerebral ischemia in mice. BMC Neurosci 2011; 12:61. [PMID: 21699735 PMCID: PMC3146423 DOI: 10.1186/1471-2202-12-61] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 06/24/2011] [Indexed: 12/04/2022] Open
Abstract
Background Bone marrow mononuclear cell (BMMC) transplantation is a promising therapy for cerebral ischemia; however, little is known if its therapeutic efficacy may be improved by co-administration of potential modulatory factors in vivo. To explore this possibility, the present study examined the effect of BMMCs and G-CSF on cell proliferation, early neuronal development and neurological function recovery in experimental cerebral ischemia relative to controls that received neither treatment. Result Ischemia/infarct area was significantly reduced in BMMCs+G-CSF group relative to animal groups treated with BMMCs only, G-CSF only or saline. Transplanted BMMCs were found to colocalize with the proliferative cell nuclear antigen (PCNA) and the immature neuronal marker doublecortin (DCX). The BMMCs+G-CSF group showed increased numerical density of cells expressing PCNA and DCX, improved performance in adhesive sticker removal test and reduced neurological function severity scores relative to other groups in a time-dependent manner. Conclusion BMMCs and G-CSF co-administration exhibits synergistic beneficial effect over time. This effect could be at least partially related to increased proliferation and differentiation of bone marrow stem cells and enhanced host brain regeneration and functional recovery. The results suggest that G-CSF can increase the therapeutic efficacy of BMMCs transplantation in an experimental mouse model of cerebral ischemia.
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Sandoval CJ, Martínez-Claros M, Bello-Medina PC, Pérez O, Ramírez-Amaya V. When are new hippocampal neurons, born in the adult brain, integrated into the network that processes spatial information? PLoS One 2011; 6:e17689. [PMID: 21408012 PMCID: PMC3052368 DOI: 10.1371/journal.pone.0017689] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 02/10/2011] [Indexed: 11/19/2022] Open
Abstract
Adult-born neurons in the dentate gyrus (DG) functionally integrate into the behaviorally relevant hippocampal networks, showing a specific Arc-expression response to spatial exploration when mature. However, it is not clear when, during the 4- to 6-week interval that is critical for survival and maturation of these neurons, this specific response develops. Therefore, we characterized Arc expression after spatial exploration or cage control conditions in adult-born neurons from rats that were injected with BrdU on one day and were sacrificed 1, 7, 15, 30, and 45 days post-BrdU injection (PBI). Triple immunostaining for NeuN, Arc, and BrdU was analyzed through the different DG layers. Arc protein expression in BrdU-positive cells was observed from day 1 to day 15 PBI but was not related to behavioral stimulation. The specific Arc-expression response to spatial exploration was observed from day 30 and 45 in about 5% of the BrdU-positive cell population. Most of the BrdU-positive neurons expressing Arc in response to spatial exploration (∼90%) were located in DG layer 1, and no Arc expression was observed in cells located in the subgranular zone (SGZ). Using the current data and that obtained previously, we propose a mathematical model suggesting that new neurons are unlikely to respond to exploration by expressing Arc after they are 301 days old, and also that in a 7-month-old rat the majority (60%) of the neurons that respond to exploration must have been born during adulthood; thus, suggesting that adult neurogenesis in the DG is highly relevant for spatial information processing.
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Affiliation(s)
- C. Jimena Sandoval
- Laboratorio de redes neuronales plásticas, Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro Qro, México
| | - Marisela Martínez-Claros
- Laboratorio de redes neuronales plásticas, Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro Qro, México
| | - Paola C. Bello-Medina
- Laboratorio de redes neuronales plásticas, Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro Qro, México
| | - Oswaldo Pérez
- Laboratorio de neurofisiología de la percepción, Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro Qro, México
| | - Víctor Ramírez-Amaya
- Laboratorio de redes neuronales plásticas, Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro Qro, México
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Rivas-Arancibia S, Guevara-Guzmán R, López-Vidal Y, Rodríguez-Martínez E, Zanardo-Gomes M, Angoa-Pérez M, Raisman-Vozari R. Oxidative stress caused by ozone exposure induces loss of brain repair in the hippocampus of adult rats. Toxicol Sci 2009; 113:187-97. [PMID: 19833740 DOI: 10.1093/toxsci/kfp252] [Citation(s) in RCA: 126] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Oxidative stress is involved in many neurodegenerative diseases. Chronic ozone exposure causes a secondary increase of reactive oxygen species, which cause an oxidative stress state in the organism. Ozone is one of the main components of photochemical pollution. Our purpose was to test that oxidative stress caused by chronic low doses of ozone, by itself, alters adult neurogenesis and causes progressive neurodegeneration in the hippocampus, which actions lead to the loss of brain plasticity in the mature central nervous system of rats. Animals were exposed to an ozone-free air stream and for 15, 30, 60, and 90 days to low doses of ozone to cause oxidative stress. Each group was then tested by (1) a spectrophotometer test to quantify lipid peroxidation (LPO) levels; (2) immunohistochemistry testing against doublecortin, Neu-N, p53, microglia, and glial fibrillary acidic protein; (3) Western blot tests for doublecortin and Neu-N; and (4) a one-trial passive avoidance test. Our results indicated that ozone causes an increase of LPO levels, morphological changes in the nucleus and the cytoplasm, and cell swelling in neurons. The Western blot shows a decrease for Neu-N and doublecortin. Activated and later phagocytic microglia and an increased number of astrocytes were found. There was a memory deficiency positively related to the amount of ozone exposure. These alterations suggest that oxidative stress caused by low doses of ozone causes dysregulation of inflammatory processes, progressive neurodegeneration, chronic loss of brain repair in the hippocampus, and brain plasticity changes in the rat analogous to those seen in Alzheimer's disease.
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Affiliation(s)
- Selva Rivas-Arancibia
- Departamento de Fisiología, Universidad Nacional Autónoma de México, AP 70-250, CP 04510 México D.F., México.
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29
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A critical period for activity-dependent synaptic development during olfactory bulb adult neurogenesis. J Neurosci 2009; 29:11852-8. [PMID: 19776271 DOI: 10.1523/jneurosci.2406-09.2009] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
New neurons integrate in large numbers into the mature olfactory bulb circuit throughout life. The factors controlling the synaptic development of adult-born neurons and their connectivity remain essentially unknown. We examined the role of activity-dependent mechanisms in the synaptic development of adult-born neurons by genetic labeling of synapses while manipulating sensory input or cell-intrinsic excitability. Sensory deprivation induced marked changes in the density of input and output synapses during the period when new neurons develop most of their synapses. In contrast, when sensory deprivation started after synaptic formation was complete, input synapses increased in one domain without detectable changes in the other dendritic domains. We then investigated the effects of genetically raising the intrinsic excitability of new neurons on their synaptic development by delivering a voltage-gated sodium channel that triggers long depolarizations. Surprisingly, genetically increasing excitability did not affect synaptic development but rescued the changes in glutamatergic input synapses caused by sensory deprivation. These experiments show that, during adult neurogenesis in the olfactory bulb, synaptic plasticity is primarily restricted to an early period during the maturation of new neurons when they are still forming synapses. The addition of cells endowed with such an initial short-lived flexibility and long-term stability may enable the processing of information by the olfactory bulb to be both versatile and reliable in the face of changing behavioral demands.
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30
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Popov VI, Kraev IV, Banks D, Davies HA, Morenkov ED, Stewart MG, Fesenko EE. Three-dimensional ultrastructural and immunohistochemical study of immature neurons in the subgranular zone of the rat dentate gyrus. Biophysics (Nagoya-shi) 2009. [DOI: 10.1134/s0006350909040174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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31
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Weisz VI, Argibay PF. A putative role for neurogenesis in neuro-computational terms: inferences from a hippocampal model. Cognition 2009; 112:229-40. [PMID: 19481201 DOI: 10.1016/j.cognition.2009.05.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2007] [Revised: 05/05/2009] [Accepted: 05/05/2009] [Indexed: 12/19/2022]
Abstract
New neurons are generated daily in the hippocampus during adult life. They are integrated into the existing neuronal circuits according to several factors such as age, physical exercise and hormonal status. At present, the role of these new neurons is debated. Computational simulations of hippocampal function allow the effects of neurogenesis to be explored, at least from a computational perspective. The present work implements a model of neurogenesis in the hippocampus with artificial neural networks, based on a standard theoretical model of biologically plausible hippocampal circuits. The performance of the model in retrieval of a variable number of patterns or memories was evaluated (episodic memory evaluation). The model increased, in a phase subsequent to initial learning, the number of granular cells by 30% relative to their initial number. In contrast to a model without neurogenesis, the retrieval of recent memories was very significantly improved, although remote memories were only slightly affected by neurogenesis. This increase in the quality of retrieval of new memories represents a clear advantage that we attribute to the neurogenesis process. This advantage becomes more significant for higher storage loads. The model presented here suggests an important functional role of neurogenesis on learning and memory.
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Affiliation(s)
- Victoria I Weisz
- Department of Theoretical Biology, Instituto de Ciencias Básicas y Medicina Experimental, Hospital Italiano de Buenos Aires, Potosí 4240 8(o) P, C1199ACL Buenos Aires, Argentina
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32
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Stocca G, Schmidt-Hieber C, Bischofberger J. Differential dendritic Ca2+ signalling in young and mature hippocampal granule cells. J Physiol 2008; 586:3795-811. [PMID: 18591186 DOI: 10.1113/jphysiol.2008.155739] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Neuronal activity is critically important for development and plasticity of dendrites, axons and synaptic connections. Although Ca(2+) is an important signal molecule for these processes, not much is known about the regulation of the dendritic Ca(2+) concentration in developing neurons. Here we used confocal Ca(2+) imaging to investigate dendritic Ca(2+) signalling in young and mature hippocampal granule cells, identified by the expression of the immature neuronal marker polysialated neural cell adhesion molecule (PSA-NCAM). Using the Ca(2+)-sensitive fluorescent dye OGB-5N, we found that both young and mature granule cells showed large action-potential evoked dendritic Ca(2+) transients with similar amplitude of approximately 200 nm, indicating active backpropagation of action potentials. However, the decay of the dendritic Ca(2+) concentration back to baseline values was substantially different with a decay time constant of 550 ms in young versus 130 ms in mature cells, leading to a more efficient temporal summation of Ca(2+) signals during theta-frequency stimulation in the young neurons. Comparison of the peak Ca(2+) concentration and the decay measured with different Ca(2+) indicators (OGB-5N, OGB-1) in the two populations of neurons revealed that the young cells had an approximately 3 times smaller endogenous Ca(2+)-binding ratio ( approximately 75 versus approximately 220) and an approximately 10 times slower Ca(2+) extrusion rate ( approximately 170 s(-1) versus approximately 1800 s(-1)). These data suggest that the large dendritic Ca(2+) signals due to low buffer capacity and slow extrusion rates in young granule cells may contribute to the activity-dependent growth and plasticity of dendrites and new synaptic connections. This will finally support differentiation and integration of young neurons into the hippocampal network.
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Affiliation(s)
- Gabriella Stocca
- Physiologisches Institut, Universitat Freiburg, Hermann-Herder-Str. 7, D-79104 Freiburg, Germany
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33
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Puzzo D, Sapienza S, Arancio O, Palmeri A. Role of phosphodiesterase 5 in synaptic plasticity and memory. Neuropsychiatr Dis Treat 2008; 4:371-87. [PMID: 18728748 PMCID: PMC2518390 DOI: 10.2147/ndt.s2447] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Phosphodiesterases (PDEs) are enzymes that break down the phosphodiesteric bond of the cyclic nucleotides, cAMP and cGMP, second messengers that regulate many biological processes. PDEs participate in the regulation of signal transduction by means of a fine regulation of cyclic nucleotides so that the response to cell stimuli is both specific and activates the correct third messengers. Several PDE inhibitors have been developed and used as therapeutic agents because they increase cyclic nucleotide levels by blocking the PDE function. In particular, sildenafil, an inhibitor of PDE5, has been mainly used in the treatment of erectile dysfunction but is now also utilized against pulmonary hypertension. This review examines the physiological role of PDE5 in synaptic plasticity and memory and the use of PDE5 inhibitors as possible therapeutic agents against disorders of the central nervous system (CNS).
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Affiliation(s)
- Daniela Puzzo
- Dept of Physiological Sciences, University of Catania Catania, Italy.
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34
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Kempermann G. The neurogenic reserve hypothesis: what is adult hippocampal neurogenesis good for? Trends Neurosci 2008; 31:163-9. [PMID: 18329110 DOI: 10.1016/j.tins.2008.01.002] [Citation(s) in RCA: 257] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 01/15/2008] [Accepted: 01/15/2008] [Indexed: 01/02/2023]
Abstract
Several theories have proposed possible functions of adult neurogenesis in learning processes on a systems level, such as the avoidance of catastrophic interference and the encoding of temporal and contextual information, and in emotional behavior. Under the assumption of such functionality of new neurons, the question arises: what are the consequences of adult hippocampal neurogenesis beyond the temporally immediate computational benefit? What might provide the evolutionary advantage of maintaining neurogenesis in the dentate gyrus but almost nowhere else? I propose that over the course of life, activity-dependently regulated adult neurogenesis reveals its true significance in the retained ability for lasting and cumulative network adaptations. The hippocampal precursor cells that generate new neurons with their particular acute function represent a 'neurogenic reserve': the potential to remain flexible and plastic in hippocampal learning when the individual is exposed to novelty and complexity.
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Affiliation(s)
- Gerd Kempermann
- Genomics of Regeneration, CRTD - Center for Regenerative Therapies Dresden, Tatzberg 47-49, 01307 Dresden, Germany.
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35
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Lanni C, Lenzken SC, Pascale A, Del Vecchio I, Racchi M, Pistoia F, Govoni S. Cognition enhancers between treating and doping the mind. Pharmacol Res 2008; 57:196-213. [DOI: 10.1016/j.phrs.2008.02.004] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Revised: 02/07/2008] [Accepted: 02/08/2008] [Indexed: 11/25/2022]
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