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Domingo-Muelas A, Duart-Abadia P, Morante-Redolat JM, Jordán-Pla A, Belenguer G, Fabra-Beser J, Paniagua-Herranz L, Pérez-Villalba A, Álvarez-Varela A, Barriga FM, Gil-Sanz C, Ortega F, Batlle E, Fariñas I. Post-transcriptional control of a stemness signature by RNA-binding protein MEX3A regulates murine adult neurogenesis. Nat Commun 2023; 14:373. [PMID: 36690670 PMCID: PMC9871011 DOI: 10.1038/s41467-023-36054-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 01/12/2023] [Indexed: 01/25/2023] Open
Abstract
Neural stem cells (NSCs) in the adult murine subependymal zone balance their self-renewal capacity and glial identity with the potential to generate neurons during the lifetime. Adult NSCs exhibit lineage priming via pro-neurogenic fate determinants. However, the protein levels of the neural fate determinants are not sufficient to drive direct differentiation of adult NSCs, which raises the question of how cells along the neurogenic lineage avoid different conflicting fate choices, such as self-renewal and differentiation. Here, we identify RNA-binding protein MEX3A as a post-transcriptional regulator of a set of stemness associated transcripts at critical transitions in the subependymal neurogenic lineage. MEX3A regulates a quiescence-related RNA signature in activated NSCs that is needed for their return to quiescence, playing a role in the long-term maintenance of the NSC pool. Furthermore, it is required for the repression of the same program at the onset of neuronal differentiation. Our data indicate that MEX3A is a pivotal regulator of adult murine neurogenesis acting as a translational remodeller.
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Grants
- EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council)
- Ministerio de Ciencia e Innovación (MICINN, Spain) - PID2020-119917RB-I00.
- Regional Government of Valencia | Conselleria d'Educació, Investigació, Cultura i Esport (Conselleria d'Educació, Investigació, Cultura i Esport de la Generalitat Valenciana)
- Ministerio de Ciencia e Innovación (MICINN, Spain) - PID2020-117937GB-I00, PID2020-119917RB-I00, PID 2019-109155RB-I00, PID2020-114227RB-I00, RyC-2015-19058, PRE2018-084838. Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED, Spain) - MICINN- CB06/05/0086.
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Affiliation(s)
- Ana Domingo-Muelas
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universidad de Valencia, Valencia, Spain
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Universidad de Valencia, Valencia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Valencia, Spain
| | - Pere Duart-Abadia
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universidad de Valencia, Valencia, Spain
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Universidad de Valencia, Valencia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Valencia, Spain
| | - Jose Manuel Morante-Redolat
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universidad de Valencia, Valencia, Spain
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Universidad de Valencia, Valencia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Valencia, Spain
| | - Antonio Jordán-Pla
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Universidad de Valencia, Valencia, Spain
| | - Germán Belenguer
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universidad de Valencia, Valencia, Spain
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Universidad de Valencia, Valencia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Valencia, Spain
| | - Jaime Fabra-Beser
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universidad de Valencia, Valencia, Spain
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Universidad de Valencia, Valencia, Spain
| | - Lucía Paniagua-Herranz
- Departamento de Bioquímica y Biología Molecular, Universidad Complutense de Madrid (UCM), Madrid, Spain
- Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain
- Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Ana Pérez-Villalba
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universidad de Valencia, Valencia, Spain
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Universidad de Valencia, Valencia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Valencia, Spain
| | - Adrián Álvarez-Varela
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Barcelona, Spain
| | - Francisco M Barriga
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Barcelona, Spain
| | - Cristina Gil-Sanz
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universidad de Valencia, Valencia, Spain
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Universidad de Valencia, Valencia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Valencia, Spain
| | - Felipe Ortega
- Departamento de Bioquímica y Biología Molecular, Universidad Complutense de Madrid (UCM), Madrid, Spain
- Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain
- Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Eduard Batlle
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Barcelona, Spain.
- ICREA, Barcelona, Spain.
| | - Isabel Fariñas
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universidad de Valencia, Valencia, Spain.
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Universidad de Valencia, Valencia, Spain.
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Valencia, Spain.
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Domingo-Muelas A, Morante-Redolat JM, Moncho-Amor V, Jordán-Pla A, Pérez-Villalba A, Carrillo-Barberà P, Belenguer G, Porlan E, Kirstein M, Bachs O, Ferrón SR, Lovell-Badge R, Fariñas I. The rates of adult neurogenesis and oligodendrogenesis are linked to cell cycle regulation through p27-dependent gene repression of SOX2. Cell Mol Life Sci 2023; 80:36. [PMID: 36627412 PMCID: PMC9832098 DOI: 10.1007/s00018-022-04676-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 12/15/2022] [Indexed: 01/12/2023]
Abstract
Cell differentiation involves profound changes in global gene expression that often has to occur in coordination with cell cycle exit. Because cyclin-dependent kinase inhibitor p27 reportedly regulates proliferation of neural progenitor cells in the subependymal neurogenic niche of the adult mouse brain, but can also have effects on gene expression, we decided to molecularly analyze its role in adult neurogenesis and oligodendrogenesis. At the cell level, we show that p27 restricts residual cyclin-dependent kinase activity after mitogen withdrawal to antagonize cycling, but it is not essential for cell cycle exit. By integrating genome-wide gene expression and chromatin accessibility data, we find that p27 is coincidentally necessary to repress many genes involved in the transit from multipotentiality to differentiation, including those coding for neural progenitor transcription factors SOX2, OLIG2 and ASCL1. Our data reveal both a direct association of p27 with regulatory sequences in the three genes and an additional hierarchical relationship where p27 repression of Sox2 leads to reduced levels of its downstream targets Olig2 and Ascl1. In vivo, p27 is also required for the regulation of the proper level of SOX2 necessary for neuroblasts and oligodendroglial progenitor cells to timely exit cell cycle in a lineage-dependent manner.
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Affiliation(s)
- Ana Domingo-Muelas
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
- Department of Cell and Developmental Biology, Smilow Center for Translational Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jose Manuel Morante-Redolat
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | - Verónica Moncho-Amor
- The Francis Crick Institute, London, NW1 1AT, UK
- IIS Biodonostia, 48013, Bilbao, Spain
| | - Antonio Jordán-Pla
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | - Ana Pérez-Villalba
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | - Pau Carrillo-Barberà
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
- Institute for Research in Biomedicine, 6500, Bellinzona, Switzerland
| | - Germán Belenguer
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307, Dresden, Germany
| | - Eva Porlan
- Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain
- Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Instituto de Salud Carlos III, Madrid, Spain
| | - Martina Kirstein
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | - Oriol Bachs
- Department of Biomedical Sciences, University of Barcelona-IDIBAPS, CIBERONC, Barcelona, Spain
| | - Sacri R Ferrón
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | | | - Isabel Fariñas
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain.
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain.
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Remesal L, Roger-Baynat I, Chirivella L, Maicas M, Brocal-Ruiz R, Pérez-Villalba A, Cucarella C, Casado M, Flames N. PBX1 acts as terminal selector for olfactory bulb dopaminergic neurons. Development 2020; 147:dev.186841. [PMID: 32156753 DOI: 10.1242/dev.186841] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 02/24/2020] [Indexed: 02/03/2023]
Abstract
Neuronal specification is a protracted process that begins with the commitment of progenitor cells and culminates with the generation of mature neurons. Many transcription factors are continuously expressed during this process but it is presently unclear how these factors modify their targets as cells transition through different stages of specification. In olfactory bulb adult neurogenesis, the transcription factor PBX1 controls neurogenesis in progenitor cells and the survival of migrating neuroblasts. Here, we show that, at later differentiation stages, PBX1 also acts as a terminal selector for the dopaminergic neuron fate. PBX1 is also required for the morphological maturation of dopaminergic neurons and to repress alternative interneuron fates, findings that expand the known repertoire of terminal-selector actions. Finally, we reveal that the temporal diversification of PBX1 functions in neuronal specification is achieved, at least in part, through the dynamic regulation of alternative splicing. In Caenorhabditis elegans, PBX/CEH-20 also acts as a dopaminergic neuron terminal selector, which suggests an ancient role for PBX factors in the regulation of terminal differentiation of dopaminergic neurons.
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Affiliation(s)
- Laura Remesal
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia, IBV-CSIC, 46010 Valencia, Spain
| | - Isabel Roger-Baynat
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia, IBV-CSIC, 46010 Valencia, Spain
| | - Laura Chirivella
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia, IBV-CSIC, 46010 Valencia, Spain
| | - Miren Maicas
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia, IBV-CSIC, 46010 Valencia, Spain
| | - Rebeca Brocal-Ruiz
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia, IBV-CSIC, 46010 Valencia, Spain
| | - Ana Pérez-Villalba
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), and Departamento de Biología Celular, Biología Funcional y Antropología Física, Universidad de Valencia, 46100 Burjassot, Spain
| | - Carme Cucarella
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III (ISCIII), Metabolic Experimental Pathology Unit, Instituto de Biomedicina de Valencia, IBV-CSIC, 46010 Valencia, Spain
| | - Marta Casado
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III (ISCIII), Metabolic Experimental Pathology Unit, Instituto de Biomedicina de Valencia, IBV-CSIC, 46010 Valencia, Spain
| | - Nuria Flames
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia, IBV-CSIC, 46010 Valencia, Spain
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Rodríguez-Arias M, Montagud-Romero S, Guardia Carrión AM, Ferrer-Pérez C, Pérez-Villalba A, Marco E, López Gallardo M, Viveros MP, Miñarro J. Social stress during adolescence activates long-term microglia inflammation insult in reward processing nuclei. PLoS One 2018; 13:e0206421. [PMID: 30365534 PMCID: PMC6203396 DOI: 10.1371/journal.pone.0206421] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 10/12/2018] [Indexed: 12/11/2022] Open
Abstract
The experience of social stress during adolescence is associated with higher vulnerability to drug use. Increases in the acquisition of cocaine self-administration, in the escalation of cocaine-seeking behavior, and in the conditioned rewarding effects of cocaine have been observed in rodents exposed to repeated social defeat (RSD). In addition, prolonged or severe stress induces a proinflammatory state with microglial activation and increased cytokine production. The aim of the present work was to describe the long-term effects induced by RSD during adolescence on the neuroinflammatory response and synaptic structure by evaluating different glial and neuronal markers. In addition to an increase in the conditioned rewarding effects of cocaine, our results showed that RSD in adolescence produced inflammatory reactivity in microglia that is prolonged into adulthood, affecting astrocytes and neurons of two reward-processing areas of the brain (the prelimbic cortex, and the nucleus accumbens core). Considered as a whole these results suggest that social stress experience modulates vulnerability to suffer a loss of glia-supporting functions and neuronal functional synaptic density due to drug consumption in later life.
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Affiliation(s)
- Marta Rodríguez-Arias
- Department of Psychobiology, Faculty of Psychology, Universitat de València, Valencia, Spain
- * E-mail:
| | - Sandra Montagud-Romero
- Department of Psychobiology, Faculty of Psychology, Universitat de València, Valencia, Spain
| | | | - Carmen Ferrer-Pérez
- Department of Psychobiology, Faculty of Psychology, Universitat de València, Valencia, Spain
| | - Ana Pérez-Villalba
- Department of Psychobiology, Faculty of Psychology, Universitat de València, Valencia, Spain
| | - Eva Marco
- Department of Animal Physiology, Faculty of Biological Sciences, Complutense University of Madrid, Madrid, Spain
| | | | - María-Paz Viveros
- Department of physiology, Faculty of Medicine, Complutense University of Madrid, Madrid, Spain
| | - José Miñarro
- Department of Psychobiology, Faculty of Psychology, Universitat de València, Valencia, Spain
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Recasens A, Dehay B, Bové J, Carballo-Carbajal I, Dovero S, Pérez-Villalba A, Fernagut PO, Blesa J, Parent A, Perier C, Fariñas I, Obeso JA, Bezard E, Vila M. Lewy body extracts from Parkinson disease brains trigger α-synuclein pathology and neurodegeneration in mice and monkeys. Ann Neurol 2014; 75:351-62. [PMID: 24243558 DOI: 10.1002/ana.24066] [Citation(s) in RCA: 460] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 10/30/2013] [Accepted: 11/12/2013] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Mounting evidence suggests that α-synuclein, a major protein component of Lewy bodies (LB), may be responsible for initiating and spreading the pathological process in Parkinson disease (PD). Supporting this concept, intracerebral inoculation of synthetic recombinant α-synuclein fibrils can trigger α-synuclein pathology in mice. However, it remains uncertain whether the pathogenic effects of recombinant synthetic α-synuclein may apply to PD-linked pathological α-synuclein and occur in species closer to humans. METHODS Nigral LB-enriched fractions containing pathological α-synuclein were purified from postmortem PD brains by sucrose gradient fractionation and subsequently inoculated into the substantia nigra or striatum of wild-type mice and macaque monkeys. Control animals received non-LB fractions containing soluble α-synuclein derived from the same nigral PD tissue. RESULTS In both mice and monkeys, intranigral or intrastriatal inoculations of PD-derived LB extracts resulted in progressive nigrostriatal neurodegeneration starting at striatal dopaminergic terminals. No neurodegeneration was observed in animals receiving non-LB fractions from the same patients. In LB-injected animals, exogenous human α-synuclein was quickly internalized within host neurons and triggered the pathological conversion of endogenous α-synuclein. At the onset of LB-induced degeneration, host pathological α-synuclein diffusely accumulated within nigral neurons and anatomically interconnected regions, both anterogradely and retrogradely. LB-induced pathogenic effects required both human α-synuclein present in LB extracts and host expression of α-synuclein. INTERPRETATION α-Synuclein species contained in PD-derived LB are pathogenic and have the capacity to initiate a PD-like pathological process, including intracellular and presynaptic accumulations of pathological α-synuclein in different brain areas and slowly progressive axon-initiated dopaminergic nigrostriatal neurodegeneration.
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Affiliation(s)
- Ariadna Recasens
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute-Center for Networked Biomedical Research on Neurodegenerative Diseases, Barcelona, Spain
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García-Gallego R, Tormos-Claramunt L, Vilanova-Salcedo P, Morales-Rodríguez R, Pérez-Villalba A, Segura-Ortí E. Efectividad de la punción seca de un punto gatillo miofascial versus manipulación de codo sobre el dolor y fuerza máxima de prensión de la mano. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.ft.2011.07.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Hernández-Rabaza V, Llorens-Martín M, Velázquez-Sánchez C, Ferragud A, Arcusa A, Gumus HG, Gómez-Pinedo U, Pérez-Villalba A, Roselló J, Trejo JL, Barcia JA, Canales JJ. Inhibition of adult hippocampal neurogenesis disrupts contextual learning but spares spatial working memory, long-term conditional rule retention and spatial reversal. Neuroscience 2008; 159:59-68. [PMID: 19138728 DOI: 10.1016/j.neuroscience.2008.11.054] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 11/19/2008] [Accepted: 11/20/2008] [Indexed: 11/30/2022]
Abstract
Neurogenesis in the adult dentate gyrus (DG) of the hippocampus has been implicated in neural plasticity and cognition but the specific functions contributed by adult-born neurons remain controversial. Here, we have explored the relationship between adult hippocampal neurogenesis and memory function using tasks which specifically require the participation of the DG. In two separate experiments several groups of rats were exposed to fractionated ionizing radiation (two sessions of 7 Gy each on consecutive days) applied either to the whole brain or focally, aiming at a region overlying the hippocampus. The immunocytochemical assays showed that the radiation significantly reduced the expression of doublecortin (DCX), a marker for immature neurons, in the dorsal DG. Ultrastructural examination of the DG region revealed disruption of progenitor cell niches several weeks after the radiation. In the first experiment, whole-brain and focal irradiation reduced DCX expression by 68% and 43%, respectively. Whole-brain and focally-irradiated rats were unimpaired compared with control rats in a matching-to-place (MTP) working memory task performed in the T-maze and in the long-term retention of the no-alternation rule. In the second experiment, focal irradiation reduced DCX expression by 36% but did not impair performance on (1) a standard non-matching-to-place (NMTP) task, (2) a more demanding NMTP task with increasingly longer within-trial delays, (3) a long-term retention test of the alternation rule and (4) a spatial reversal task. However, rats irradiated focally showed clear deficits in a "purely" contextual fear-conditioning task at short and long retention intervals. These data demonstrate that reduced adult hippocampal neurogenesis produces marked deficits in the rapid acquisition of emotionally relevant contextual information but spares spatial working memory function, the long-term retention of acquired spatial rules and the ability to flexibly modify learned spatial strategies.
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Affiliation(s)
- V Hernández-Rabaza
- Biopsychology and Comparative Neuroscience Unit, Cavanilles Institute (ICBiBE), University of Valencia-General Foundation, Polígono de la Coma s/n, Paterna, 46980 Valencia, Spain
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8
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Olucha-Bordonau FE, Pérez-Villalba A, Teruel-Martí V, Ruiz-Torner A. Chemical divisions in the medial geniculate body and surrounding paralaminar nuclei of the rat: quantitative comparison of cell density, NADPH diaphorase, acetyl cholin esterase and basal expression of c-fos. J Chem Neuroanat 2005; 28:147-62. [PMID: 15482901 DOI: 10.1016/j.jchemneu.2004.05.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2003] [Revised: 05/12/2004] [Accepted: 06/02/2004] [Indexed: 10/26/2022]
Abstract
Quantitative methods of cell density, the intensities of both acetyl cholinesterase (AChE) and NADPH diaphorase (NADPHd), as well as the basal expression of c-fos, have been carried out in order to study the anatomical divisions of the medial geniculate body (MGB) and the group of nuclei located ventromedially to the MGB called the paralaminar complex (PL). The MGB was composed of the dorsal (MGd), and the ventral (MGv) divisions. We included the medial, or the magnocellular division (MGm), in the PL complex. MGd was composed of a dorsolateral (DL) core and a belt. The belt was composed of the suprageniculate (SG), the deep dorsal (DD), the caudo-medial (CM) and the caudo-dorsal (CD) nuclei. In the MGv, the basal expression of c-fos was the only way to trace a clear boundary between the ovoid (Ov) and the ventrolateral (VL) divisions. However, the marginal zone (MZ) was clearly and contrastingly different. The PL was considered to be composed of: the MGm, the posterior intralaminar nucleus (PIN), the peripeduncular nucleus (PP) and the nucleus subparafascicularis lateralis (SPFL). The MGm and the PIN share most of the chemical features, meanwhile both SPFL and PP displayed different patterns of NADPHd reactivity. The study of cell density on Giemsa stained sections confirmed main divisions of the area. AChE and NADPHd methods allowed the main MGB divisions to be discriminated. The differences between subdivisions were emphasized when cell density and c-fos activity were quantified in each nucleus. Each MGB division displayed a different pattern of c-fos activity under basal conditions. Thus, c-fos basal expression was a particular feature in each MGB or PL nucleus.
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Affiliation(s)
- Francisco E Olucha-Bordonau
- Dpt. Anatomia i Embriologia Humana, Fac. de Medicina i Odontologia, University València, Av. Blasco Ibáñez 15, E-46010-Valencia, Spain.
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