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Li H, Tamura R, Hayashi D, Asai H, Koga J, Ando S, Yokota S, Kaneko J, Sakurai K, Sumiyoshi A, Yamamoto T, Hikishima K, Tanaka KZ, McHugh TJ, Hisatsune T. Silencing dentate newborn neurons alters excitatory/inhibitory balance and impairs behavioral inhibition and flexibility. SCIENCE ADVANCES 2024; 10:eadk4741. [PMID: 38198539 PMCID: PMC10780870 DOI: 10.1126/sciadv.adk4741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 12/13/2023] [Indexed: 01/12/2024]
Abstract
Adult neurogenesis confers the hippocampus with unparalleled neural plasticity, essential for intricate cognitive functions. The specific influence of sparse newborn neurons (NBNs) in modulating neural activities and subsequently steering behavior, however, remains obscure. Using an engineered NBN-tetanus toxin mouse model (NBN-TeTX), we noninvasively silenced NBNs, elucidating their crucial role in impulse inhibition and cognitive flexibility as evidenced through Morris water maze reversal learning and Go/Nogo task in operant learning. Task-based functional MRI (tb-fMRI) paired with operant learning revealed dorsal hippocampal hyperactivation during the Nogo task in male NBN-TeTX mice, suggesting that hippocampal hyperexcitability might underlie the observed behavioral deficits. Additionally, resting-state fMRI (rs-fMRI) exhibited enhanced functional connectivity between the dorsal and ventral dentate gyrus following NBN silencing. Further investigations into the activities of PV+ interneurons and mossy cells highlighted the indispensability of NBNs in maintaining the hippocampal excitation/inhibition balance. Our findings emphasize that the neural plasticity driven by NBNs extensively modulates the hippocampus, sculpting inhibitory control and cognitive flexibility.
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Affiliation(s)
- Haowei Li
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Risako Tamura
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Daiki Hayashi
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Hirotaka Asai
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Junya Koga
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Shota Ando
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Sayumi Yokota
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Jun Kaneko
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Keisuke Sakurai
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Akira Sumiyoshi
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Tadashi Yamamoto
- Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Keigo Hikishima
- Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Kazumasa Z. Tanaka
- Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
- Laboratory for Circuit and Behavioral Physiology, RIKEN Center for Brain Science, Saitama, Japan
| | - Thomas J. McHugh
- Laboratory for Circuit and Behavioral Physiology, RIKEN Center for Brain Science, Saitama, Japan
| | - Tatsuhiro Hisatsune
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
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Rosell-Valle C, Pedraza C, Manuel I, Moreno-Rodríguez M, Rodríguez-Puertas R, Castilla-Ortega E, Caramés JM, Gómez Conde AI, Zambrana-Infantes E, Ortega-Pinazo J, Serrano-Castro PJ, Chun J, Rodríguez De Fonseca F, Santín LJ, Estivill-Torrús G. Chronic central modulation of LPA/LPA receptors-signaling pathway in the mouse brain regulates cognition, emotion, and hippocampal neurogenesis. Prog Neuropsychopharmacol Biol Psychiatry 2021; 108:110156. [PMID: 33152386 DOI: 10.1016/j.pnpbp.2020.110156] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/25/2020] [Accepted: 10/27/2020] [Indexed: 02/05/2023]
Abstract
Several studies have demonstrated that lysophosphatidic acid (LPA) acts through its LPA receptors in multiple biological and behavioral processes, including adult hippocampal neurogenesis, hippocampal-dependent memory, and emotional regulation. However, analyses of the effects have typically involved acute treatments, and there is no information available regarding the effect of the chronic pharmacological modulation of the LPA/LPA receptors-signaling pathway. Thus, we analyzed the effect of the chronic (21 days) and continuous intracerebroventricular (ICV) infusion of C18:1 LPA and the LPA1-3 receptor antagonist Ki16425 in behavior and adult hippocampal neurogenesis. Twenty-one days after continuous ICV infusions, mouse behaviors in the open field test, Y-maze test and forced swimming test were assessed. In addition, the hippocampus was examined for c-Fos expression and α-CaMKII and phospho-α-CaMKII levels. The current study demonstrates that chronic C18:1 LPA produced antidepressant effects, improved spatial working memory, and enhanced adult hippocampal neurogenesis. In contrast, chronic LPA1-3 receptor antagonism disrupted exploratory activity and spatial working memory, induced anxiety and depression-like behaviors and produced an impairment of hippocampal neurogenesis. While these effects were accompanied by an increase in neuronal activation in the DG of C18:1 LPA-treated mice, Ki16425-treated mice showed reduced neuronal activation in CA3 and CA1 hippocampal subfields. Treatment with the antagonist also induced an imbalance in the expression of basal/activated α-CaMKII protein forms. These outcomes indicate that the chronic central modulation of the LPA receptors-signaling pathway in the brain regulates cognition and emotion, likely comprising hippocampal-dependent mechanisms. The use of pharmacological modulation of this pathway in the brain may potentially be targeted for the treatment of several neuropsychiatric conditions.
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Affiliation(s)
- Cristina Rosell-Valle
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; Unidad de Gestión Clínica de Neurociencias, Hospital Regional Universitario de Málaga, Málaga, Spain; Departamento de Psicobiología y Metodología de las Ciencias del Comportamiento, Universidad de Málaga, Málaga, Spain; Unidad de Producción de Reprogramación Celular, Red Andaluza para el diseño y traslación de Terapias Avanzadas, Junta de Andalucía, Spain
| | - Carmen Pedraza
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; Departamento de Psicobiología y Metodología de las Ciencias del Comportamiento, Universidad de Málaga, Málaga, Spain
| | - Iván Manuel
- Departamento de Farmacología, Facultad de Medicina y Enfermería, Universidad del País Vasco (UPV/EHU), Leioa, Spain
| | - Marta Moreno-Rodríguez
- Departamento de Farmacología, Facultad de Medicina y Enfermería, Universidad del País Vasco (UPV/EHU), Leioa, Spain
| | - Rafael Rodríguez-Puertas
- Departamento de Farmacología, Facultad de Medicina y Enfermería, Universidad del País Vasco (UPV/EHU), Leioa, Spain
| | - Estela Castilla-Ortega
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, Málaga, Spain
| | - José María Caramés
- Centre for Discovery Brain Sciences, Edinburgh Neuroscience, University of Edinburgh, Edinburgh, UK
| | - Ana I Gómez Conde
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; ECAI de Microscopía, Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
| | - Emma Zambrana-Infantes
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; Departamento de Psicobiología y Metodología de las Ciencias del Comportamiento, Universidad de Málaga, Málaga, Spain
| | - Jesús Ortega-Pinazo
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; Unidad de Gestión Clínica de Neurociencias, Hospital Regional Universitario de Málaga, Málaga, Spain
| | - Pedro J Serrano-Castro
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; Unidad de Gestión Clínica de Neurociencias, Hospital Regional Universitario de Málaga, Málaga, Spain
| | - Jerold Chun
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Fernando Rodríguez De Fonseca
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; Unidad de Gestión Clínica de Salud Mental, Hospital Regional Universitario de Málaga, Málaga, Spain
| | - Luis J Santín
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; Departamento de Psicobiología y Metodología de las Ciencias del Comportamiento, Universidad de Málaga, Málaga, Spain.
| | - Guillermo Estivill-Torrús
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain; Unidad de Gestión Clínica de Neurociencias, Hospital Regional Universitario de Málaga, Málaga, Spain.
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Lunardi P, Mansk LMZ, Jaimes LF, Pereira GS. On the novel mechanisms for social memory and the emerging role of neurogenesis. Brain Res Bull 2021; 171:56-66. [PMID: 33753208 DOI: 10.1016/j.brainresbull.2021.03.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/24/2021] [Accepted: 03/08/2021] [Indexed: 01/25/2023]
Abstract
Social memory (SM) is a key element in social cognition and it encompasses the neural representation of conspecifics, an essential information to guide behavior in a social context. Here we evaluate classical and cutting-edge studies on neurobiology of SM, using as a guiding principle behavioral tasks performed in adult rodents. Our review highlights the relevance of the hippocampus, especially the CA2 region, as a neural substrate for SM and suggest that neural ensembles in the olfactory bulb may also encode SM traces. Compared to other hippocampus-dependent memories, much remains to be done to describe the neurobiological foundations of SM. Nonetheless, we argue that special attention should be paid to neurogenesis. Finally, we pinpoint the remaining open question on whether the hippocampal adult neurogenesis acts through pattern separation to permit the discrimination of highly similar stimuli during behavior.
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Affiliation(s)
- Paula Lunardi
- Núcleo de Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Lara M Z Mansk
- Núcleo de Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Laura F Jaimes
- Núcleo de Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Grace S Pereira
- Núcleo de Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
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4
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Koyanagi I, Sonomura K, Naoi T, Ohnishi T, Kaneko N, Sawamoto K, Sato TA, Sakaguchi M. Metabolic fingerprints of fear memory consolidation during sleep. Mol Brain 2021; 14:30. [PMID: 33568175 PMCID: PMC7874630 DOI: 10.1186/s13041-021-00733-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 01/08/2021] [Indexed: 01/05/2023] Open
Abstract
Metabolites underlying brain function and pathology are not as well understood as genes. Here, we applied a novel metabolomics approach to further understand the mechanisms of memory processing in sleep. As hippocampal dentate gyrus neurons are known to consolidate contextual fear memory, we analyzed real-time changes in metabolites in the dentate gyrus in different sleep-wake states in mice. Throughout the study, we consistently detected more than > 200 metabolites. Metabolite profiles changed dramactically upon sleep-wake state transitions, leading to a clear separation of phenotypes between wakefulness and sleep. By contrast, contextual fear memory consolidation induced less obvious metabolite phenotypes. However, changes in purine metabolites were observed upon both sleep-wake state transitions and contextual fear memory consolidation. Dietary supplementation of certain purine metabolites impaired correlations between conditioned fear responses before and after memory consolidation. These results point toward the importance of purine metabolism in fear memory processing during sleep.
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Affiliation(s)
- Iyo Koyanagi
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, Japan
- Doctoral Program in Neuroscience, Degree Programs in Comprehensive Human Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Kazuhiro Sonomura
- Life Science Research Center, Technology Research Laboratory, Shimadzu Corporation, Kyoto, Japan
| | - Toshie Naoi
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Takaaki Ohnishi
- Graduate School of Artificial Intelligence and Science, Rikkyo University, Tokyo, Japan
| | - Naoko Kaneko
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi, 467-8601, Japan
- Division of Neural Development and Regeneration, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8585, Japan
| | - Kazunobu Sawamoto
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi, 467-8601, Japan
- Division of Neural Development and Regeneration, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8585, Japan
| | - Taka-Aki Sato
- Life Science Research Center, Technology Research Laboratory, Shimadzu Corporation, Kyoto, Japan
- R&D Center for Precision Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Masanori Sakaguchi
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, Japan.
- Doctoral Program in Neuroscience, Degree Programs in Comprehensive Human Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
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5
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Severe reactive astrocytes precipitate pathological hallmarks of Alzheimer's disease via H 2O 2- production. Nat Neurosci 2020; 23:1555-1566. [PMID: 33199896 DOI: 10.1038/s41593-020-00735-y] [Citation(s) in RCA: 141] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 10/07/2020] [Indexed: 12/29/2022]
Abstract
Although the pathological contributions of reactive astrocytes have been implicated in Alzheimer's disease (AD), their in vivo functions remain elusive due to the lack of appropriate experimental models and precise molecular mechanisms. Here, we show the importance of astrocytic reactivity on the pathogenesis of AD using GiD, a newly developed animal model of reactive astrocytes, where the reactivity of astrocytes can be manipulated as mild (GiDm) or severe (GiDs). Mechanistically, excessive hydrogen peroxide (H2O2) originated from monoamine oxidase B in severe reactive astrocytes causes glial activation, tauopathy, neuronal death, brain atrophy, cognitive impairment and eventual death, which are significantly prevented by AAD-2004, a potent H2O2 scavenger. These H2O2--induced pathological features of AD in GiDs are consistently recapitulated in a three-dimensional culture AD model, virus-infected APP/PS1 mice and the brains of patients with AD. Our study identifies H2O2 from severe but not mild reactive astrocytes as a key determinant of neurodegeneration in AD.
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Bielefeld P, Durá I, Danielewicz J, Lucassen P, Baekelandt V, Abrous D, Encinas J, Fitzsimons C. Insult-induced aberrant hippocampal neurogenesis: Functional consequences and possible therapeutic strategies. Behav Brain Res 2019; 372:112032. [DOI: 10.1016/j.bbr.2019.112032] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 05/29/2019] [Accepted: 06/10/2019] [Indexed: 02/08/2023]
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7
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Bullmann T, Feneberg E, Kretzschmann TP, Ogunlade V, Holzer M, Arendt T. Hibernation Impairs Odor Discrimination - Implications for Alzheimer's Disease. Front Neuroanat 2019; 13:69. [PMID: 31379517 PMCID: PMC6646461 DOI: 10.3389/fnana.2019.00069] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 06/21/2019] [Indexed: 11/13/2022] Open
Abstract
Reversible formation of PHF-like phosphorylated tau, an early feature of Alzheimer's disease (AD) was previously shown to occur in torpor during hibernation in the Golden hamster (Syrian hamster, Mesocricetus auratus). Here, we tackled the question to what extent hibernating Golden hamsters can serve as a model for the early stage of AD. During early AD, anosmia, the loss of olfactory function, is a common and typical feature. We, thus, investigated tau phosphorylation, synaptic plasticity and behavioral physiology of the olfactory system during hibernation. Tau was phosphorylated on several AD-relevant epitopes, and distribution of PHF-like phosphorylated tau in the olfactory bulb was quite similar to what is seen in AD. Tau phosphorylation was not associated with a destabilization of microtubules and did not lead to fibril formation. Previously, we observed a transient spine reduction in pyramidal cells in the hippocampus, which is correlated with the distribution of phosphorylated tau. Here we show that granule cells in the olfactory bulb are devoid of phosphorylated tau and maintain their spines number during torpor. No reduction of synaptic proteins was observed. However, hibernation did impair the recall performance in a two-odor discrimination task. We conclude that hibernation is associated with a specific olfactory memory deficit, which might not be attributed to the formation of PHF-like phosphorylated tau within the olfactory bulb. We discuss a possible involvement of modulatory input provided by cholinergic neurons in the basal forebrain, which are affected by hibernation.
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Affiliation(s)
- Torsten Bullmann
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Emily Feneberg
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Tanja Petra Kretzschmann
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Vera Ogunlade
- Department of Neuropathology, University of Leipzig, Leipzig, Germany
| | - Max Holzer
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Thomas Arendt
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
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Velazco-Mendoza M, Camacho FJ, Paredes RG, Portillo W. The First Mating Experience Induces New Neurons in the Olfactory Bulb in Male Mice. Neuroscience 2018; 396:166-174. [PMID: 30471356 DOI: 10.1016/j.neuroscience.2018.11.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 11/12/2018] [Accepted: 11/13/2018] [Indexed: 12/17/2022]
Abstract
In rodents, neurogenesis in the olfactory bulbs (OBs) is enhanced by exposure to olfactory enriched environments including sexually relevant odors. In the present study we evaluated whether sexual stimulation in male mice increases the number of newly generated cells that reach the OB and whether these cells differentiate into neurons. To this end, we used sexually naive male C57BL mice randomly assigned to one of three groups: (1) control, in which animals were left alone in their home cages; (2) exposure, in which animals were exposed to a receptive female precluding any physical contact; and (3) mating, in which males copulated with females. Males were given three injections of the DNA synthesis marker 5-bromo-2'-deoxyuridine (BrdU) 2 h before, at the end and 2 h after the test. Fifteen days after BrdU administration, brains were removed and processed to identify new cells and evaluate if they had differentiated into neurons in the granular (GR), mitral (MI) and glomerular (GL) cell layers of the main and accessory OB (MOB and AOB, respectively). We found an increase in the percentage of new cells that differentiate into neurons in the GL cell layer of the MOB of males from the mating group compared with those from the exposure and control groups. No differences were found in the number of new cells or percentage of new neurons in the rest of the analyzed regions. In male mice, the first sexual experience increases the percentage of new cells that differentiate into neurons in the GL cell layer of the MOB.
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Affiliation(s)
- M Velazco-Mendoza
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, México
| | - F J Camacho
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, México
| | - R G Paredes
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, México
| | - W Portillo
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, México.
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Tong MT, Kim TYP, Cleland TA. Kinase activity in the olfactory bulb is required for odor memory consolidation. ACTA ACUST UNITED AC 2018; 25:198-205. [PMID: 29661832 PMCID: PMC5903401 DOI: 10.1101/lm.046615.117] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 02/05/2018] [Indexed: 12/25/2022]
Abstract
Long-term fear memory formation in the hippocampus and neocortex depends upon brain-derived neurotrophic factor (BDNF) signaling after acquisition. Incremental, appetitive odor discrimination learning is thought to depend substantially on the differentiation of adult-born neurons within the olfactory bulb (OB)—a process that is closely associated with BDNF signaling. We sought to elucidate the role of neurotrophin signaling within the OB on odor memory consolidation. Male mice were trained on odor–reward associative discriminations after bilateral infusion of the kinase inhibitor K252a, or vehicle control, into the OB. K252a is a partially selective inhibitor of tyrosine kinase (Trk) receptors, including the TrkB receptor for BDNF, though it also inhibits other plasticity-related kinases such as PKC and CaMKII/IV. K252a infusion into the OB did not impair odor acquisition or short-term (2 h) memory for the learned discriminations, but significantly impaired long-term (48 h) odor memory (LTM). This LTM deficit also was associated with reduced selectivity for the conditioned odorant in a reward-seeking digging task. Infusions of K252a immediately prior to testing did not impair LTM recall. These results indicate that kinase activation in the OB is required for the consolidation of odor memory of incrementally acquired information.
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Affiliation(s)
- Michelle T Tong
- Department of Psychology, Cornell University, Ithaca, New York 14853, USA .,Department of Psychology, Earlham College, Richmond, Indiana 47374, USA
| | - Tae-Young P Kim
- Department of Psychology, Cornell University, Ithaca, New York 14853, USA
| | - Thomas A Cleland
- Department of Psychology, Cornell University, Ithaca, New York 14853, USA
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Abstract
Odor–reward association during appetitive learning is a fundamental process that requires multiple forms of plasticity. In the adult olfactory bulb, the continual production of newborn interneurons contributes to the functional plasticity of the system, placing the newcomers in a key position to participate in olfactory associative learning. Here, we demonstrate that adult-born neurons, but not preexisting ones, contain information about learned positive value. Moreover, specific heightening of this signal improves associative learning and odor value update and is enough in some cases to trigger behavior even without odor stimulus. Collectively, our findings show an important role of this adult-born interneuron population in odor–reward association and unveil the relevance of odor value encoding at early stages of sensory processing. Olfaction is an important sensory modality driving fundamental behaviors. During odor-dependent learning, a positive value is commonly assigned to an odorant, and multiple forms of plasticity are involved when such odor–reward associations are formed. In rodents, one of the mechanisms underlying plasticity in the olfactory bulb consists in recruiting new neurons daily throughout life. However, it is still unknown whether adult-born neurons might participate in encoding odor value. Here, we demonstrate that exposure to reward-associated odors specifically increases activity of adult-born neurons but not preexisting neurons. Remarkably, adult-born neuron activation during rewarded odor presentation heightens discrimination learning and enhances the ability to update the odor value during reversal association. Moreover, in some cases, activation of this interneuron population can trigger olfactory learning without sensory stimulation. Taken together, our results show a specific involvement of adult-born neurons in facilitating odor–reward association during adaptive learning.
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11
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Galinato MH, Takashima Y, Fannon MJ, Quach LW, Morales Silva RJ, Mysore KK, Terranova MJ, Dutta RR, Ostrom RW, Somkuwar SS, Mandyam CD. Neurogenesis during Abstinence Is Necessary for Context-Driven Methamphetamine-Related Memory. J Neurosci 2018; 38:2029-2042. [PMID: 29363584 PMCID: PMC5824740 DOI: 10.1523/jneurosci.2011-17.2018] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 12/05/2017] [Accepted: 01/09/2018] [Indexed: 12/22/2022] Open
Abstract
Abstinence from methamphetamine addiction enhances proliferation and differentiation of neural progenitors and increases adult neurogenesis in the dentate gyrus (DG). We hypothesized that neurogenesis during abstinence contributes to context-driven drug-seeking behaviors. To test this hypothesis, the pharmacogenetic rat model (GFAP-TK rats) was used to conditionally and specifically ablate neurogenesis in the DG. Male GFAP-TK rats were trained to self-administer methamphetamine or sucrose and were administered the antiviral drug valganciclovir (Valcyte) to produce apoptosis of actively dividing GFAP type 1 stem-like cells to inhibit neurogenesis during abstinence. Hippocampus tissue was stained for Ki-67, NeuroD, and DCX to measure levels of neural progenitors and immature neurons, and was stained for synaptoporin to determine alterations in mossy fiber tracts. DG-enriched tissue punches were probed for CaMKII to measure alterations in plasticity-related proteins. Whole-cell patch-clamp recordings were performed in acute brain slices from methamphetamine naive (controls) and methamphetamine experienced animals (+/-Valcyte). Spontaneous EPSCs and intrinsic excitability were recorded from granule cell neurons (GCNs). Reinstatement of methamphetamine seeking enhanced autophosphorylation of CaMKII, reduced mossy fiber density, and induced hyperexcitability of GCNs. Inhibition of neurogenesis during abstinence prevented context-driven methamphetamine seeking, and these effects correlated with reduced autophosphorylation of CaMKII, increased mossy fiber density, and reduced the excitability of GCNs. Context-driven sucrose seeking was unaffected. Together, the loss-of-neurogenesis data demonstrate that neurogenesis during abstinence assists with methamphetamine context-driven memory in rats, and that neurogenesis during abstinence is essential for the expression of synaptic proteins and plasticity promoting context-driven drug memory.SIGNIFICANCE STATEMENT Our work uncovers a mechanistic relationship between neurogenesis in the dentate gyrus and drug seeking. We report that the suppression of excessive neurogenesis during abstinence from methamphetamine addiction by a confirmed phamacogenetic approach blocked context-driven methamphetamine reinstatement and prevented maladaptive changes in expression and activation of synaptic proteins and basal synaptic function associated with learning and memory in the dentate gyrus. Our study is the first to demonstrate an interesting and dysfunctional role of adult hippocampal neurogenesis during abstinence to drug-seeking behavior in animals self-administering escalating amounts of methamphetamine. Together, these results support a direct role for the importance of adult neurogenesis during abstinence in compulsive-like drug reinstatement.
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Affiliation(s)
- Melissa H Galinato
- Departments of Neuroscience
- Veterans Medical Research Foundation, VA San Diego Healthcare System, San Diego, California 92161, and
- Department of Neuroscience, The Scripps Research Institute, La Jolla, California 92037
| | - Yoshio Takashima
- Anesthesiology, University of California San Diego, San Diego, California 92093
- Veterans Medical Research Foundation, VA San Diego Healthcare System, San Diego, California 92161, and
| | - McKenzie J Fannon
- Veterans Medical Research Foundation, VA San Diego Healthcare System, San Diego, California 92161, and
| | - Leon W Quach
- Veterans Medical Research Foundation, VA San Diego Healthcare System, San Diego, California 92161, and
| | | | - Karthik K Mysore
- Veterans Medical Research Foundation, VA San Diego Healthcare System, San Diego, California 92161, and
| | - Michael J Terranova
- Veterans Medical Research Foundation, VA San Diego Healthcare System, San Diego, California 92161, and
| | - Rahul R Dutta
- Department of Neuroscience, The Scripps Research Institute, La Jolla, California 92037
| | - Ryan W Ostrom
- Veterans Medical Research Foundation, VA San Diego Healthcare System, San Diego, California 92161, and
| | - Sucharita S Somkuwar
- Veterans Medical Research Foundation, VA San Diego Healthcare System, San Diego, California 92161, and
| | - Chitra D Mandyam
- Departments of Neuroscience,
- Anesthesiology, University of California San Diego, San Diego, California 92093
- Veterans Medical Research Foundation, VA San Diego Healthcare System, San Diego, California 92161, and
- Department of Neuroscience, The Scripps Research Institute, La Jolla, California 92037
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12
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Domenichini F, Terrié E, Arnault P, Harnois T, Magaud C, Bois P, Constantin B, Coronas V. Store-Operated Calcium Entries Control Neural Stem Cell Self-Renewal in the Adult Brain Subventricular Zone. Stem Cells 2018; 36:761-774. [PMID: 29359518 DOI: 10.1002/stem.2786] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 12/19/2017] [Accepted: 01/10/2018] [Indexed: 12/13/2022]
Abstract
The subventricular zone (SVZ) is the major stem cell niche in the brain of adult mammals. Within this region, neural stem cells (NSC) proliferate, self-renew and give birth to neurons and glial cells. Previous studies underlined enrichment in calcium signaling-related transcripts in adult NSC. Because of their ability to mobilize sustained calcium influxes in response to a wide range of extracellular factors, store-operated channels (SOC) appear to be, among calcium channels, relevant candidates to induce calcium signaling in NSC whose cellular activities are continuously adapted to physiological signals from the microenvironment. By Reverse Transcription Polymerase Chain Reaction (RT-PCR), Western blotting and immunocytochemistry experiments, we demonstrate that SVZ cells express molecular actors known to build up SOC, namely transient receptor potential canonical 1 (TRPC1) and Orai1, as well as their activator stromal interaction molecule 1 (STIM1). Calcium imaging reveals that SVZ cells display store-operated calcium entries. Pharmacological blockade of SOC with SKF-96365 or YM-58483 (also called BTP2) decreases proliferation, impairs self-renewal by shifting the type of SVZ stem cell division from symmetric proliferative to asymmetric, thereby reducing the stem cell population. Brain section immunostainings show that TRPC1, Orai1, and STIM1 are expressed in vivo, in SOX2-positive SVZ NSC. Injection of SKF-96365 in brain lateral ventricle diminishes SVZ cell proliferation and reduces the ability of SVZ cells to form neurospheres in vitro. The present study combining in vitro and in vivo approaches uncovers a major role for SOC in the control of SVZ NSC population and opens new fields of investigation for stem cell biology in health and disease. Stem Cells 2018;36:761-774.
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Affiliation(s)
- Florence Domenichini
- Signalisation et Transports Ioniques Membranaires, University of Poitiers, CNRS ERL 7003, Poitiers Cedex 09, France
| | - Elodie Terrié
- Signalisation et Transports Ioniques Membranaires, University of Poitiers, CNRS ERL 7003, Poitiers Cedex 09, France
| | - Patricia Arnault
- Signalisation et Transports Ioniques Membranaires, University of Poitiers, CNRS ERL 7003, Poitiers Cedex 09, France
| | - Thomas Harnois
- Signalisation et Transports Ioniques Membranaires, University of Poitiers, CNRS ERL 7003, Poitiers Cedex 09, France
| | - Christophe Magaud
- Signalisation et Transports Ioniques Membranaires, University of Poitiers, CNRS ERL 7003, Poitiers Cedex 09, France
| | - Patrick Bois
- Signalisation et Transports Ioniques Membranaires, University of Poitiers, CNRS ERL 7003, Poitiers Cedex 09, France
| | - Bruno Constantin
- Signalisation et Transports Ioniques Membranaires, University of Poitiers, CNRS ERL 7003, Poitiers Cedex 09, France
| | - Valérie Coronas
- Signalisation et Transports Ioniques Membranaires, University of Poitiers, CNRS ERL 7003, Poitiers Cedex 09, France
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13
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Mastrodonato A, Barbati SA, Leone L, Colussi C, Gironi K, Rinaudo M, Piacentini R, Denny CA, Grassi C. Olfactory memory is enhanced in mice exposed to extremely low-frequency electromagnetic fields via Wnt/β-catenin dependent modulation of subventricular zone neurogenesis. Sci Rep 2018; 8:262. [PMID: 29321633 PMCID: PMC5762682 DOI: 10.1038/s41598-017-18676-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 12/15/2017] [Indexed: 12/03/2022] Open
Abstract
Exposure to extremely low-frequency electromagnetic fields (ELFEF) influences the expression of key target genes controlling adult neurogenesis and modulates hippocampus-dependent memory. Here, we assayed whether ELFEF stimulation affects olfactory memory by modulating neurogenesis in the subventricular zone (SVZ) of the lateral ventricle, and investigated the underlying molecular mechanisms. We found that 30 days after the completion of an ELFEF stimulation protocol (1 mT; 50 Hz; 3.5 h/day for 12 days), mice showed enhanced olfactory memory and increased SVZ neurogenesis. These effects were associated with upregulated expression of mRNAs encoding for key regulators of adult neurogenesis and were mainly dependent on the activation of the Wnt pathway. Indeed, ELFEF stimulation increased Wnt3 mRNA expression and nuclear localization of its downstream target β-catenin. Conversely, inhibition of Wnt3 by Dkk-1 prevented ELFEF-induced upregulation of neurogenic genes and abolished ELFEF’s effects on olfactory memory. Collectively, our findings suggest that ELFEF stimulation increases olfactory memory via enhanced Wnt/β-catenin signaling in the SVZ and point to ELFEF as a promising tool for enhancing SVZ neurogenesis and olfactory function.
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Affiliation(s)
- Alessia Mastrodonato
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy.,Columbia University, Department of Psychiatry, New York, NY, 10032, USA.,Research Foundation for Mental Hygiene Inc. (RFMH), Division of Integrative Neuroscience, New York State Psychiatric Institute (NYSPI), New York, NY, 10032, USA
| | | | - Lucia Leone
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy
| | - Claudia Colussi
- CNR, Institute of Cell Biology and Neurobiology, Monterotondo (RM), 00015, Italy
| | - Katia Gironi
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy
| | - Marco Rinaudo
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy
| | - Roberto Piacentini
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy
| | - Christine A Denny
- Columbia University, Department of Psychiatry, New York, NY, 10032, USA.,Research Foundation for Mental Hygiene Inc. (RFMH), Division of Integrative Neuroscience, New York State Psychiatric Institute (NYSPI), New York, NY, 10032, USA
| | - Claudio Grassi
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy. .,Fondazione Policlinico Universitario A. Gemelli, Rome, 00168, Italy.
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14
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Malvaut S, Gribaudo S, Hardy D, David LS, Daroles L, Labrecque S, Lebel-Cormier MA, Chaker Z, Coté D, De Koninck P, Holzenberger M, Trembleau A, Caille I, Saghatelyan A. CaMKIIα Expression Defines Two Functionally Distinct Populations of Granule Cells Involved in Different Types of Odor Behavior. Curr Biol 2017; 27:3315-3329.e6. [PMID: 29107547 DOI: 10.1016/j.cub.2017.09.058] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 08/23/2017] [Accepted: 09/27/2017] [Indexed: 12/25/2022]
Abstract
Granule cells (GCs) in the olfactory bulb (OB) play an important role in odor information processing. Although they have been classified into various neurochemical subtypes, the functional roles of these subtypes remain unknown. We used in vivo two-photon Ca2+ imaging combined with cell-type-specific identification of GCs in the mouse OB to examine whether functionally distinct GC subtypes exist in the bulbar network. We showed that half of GCs express Ca2+/calmodulin-dependent protein kinase IIα (CaMKIIα+) and that these neurons are preferentially activated by olfactory stimulation. The higher activity of CaMKIIα+ neurons is due to the weaker inhibitory input that they receive compared to their CaMKIIα-immunonegative (CaMKIIα-) counterparts. In line with these functional data, immunohistochemical analyses showed that 75%-90% of GCs expressing the immediate early gene cFos are CaMKIIα+ in naive animals and in mice that have been exposed to a novel odor and go/no-go operant conditioning, or that have been subjected to long-term associative memory and spontaneous habituation/dishabituation odor discrimination tasks. On the other hand, a perceptual learning task resulted in increased activation of CaMKIIα- cells. Pharmacogenetic inhibition of CaMKIIα+ GCs revealed that this subtype is involved in habituation/dishabituation and go/no-go odor discrimination, but not in perceptual learning. In contrast, pharmacogenetic inhibition of GCs in a subtype-independent manner affected perceptual learning. Our results indicate that functionally distinct populations of GCs exist in the OB and that they play distinct roles during different odor tasks.
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Affiliation(s)
- Sarah Malvaut
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada
| | - Simona Gribaudo
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, 75005 Paris, France
| | - Delphine Hardy
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada
| | | | - Laura Daroles
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, 75005 Paris, France
| | - Simon Labrecque
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada
| | | | - Zayna Chaker
- INSERM and Sorbonne Universités, UPMC, Centre de Recherche Saint-Antoine, Paris, France
| | - Daniel Coté
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada; Faculté des Sciences et de Génie, Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Paul De Koninck
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada; Faculté des Sciences et de Génie, Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Martin Holzenberger
- INSERM and Sorbonne Universités, UPMC, Centre de Recherche Saint-Antoine, Paris, France
| | - Alain Trembleau
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, 75005 Paris, France
| | - Isabelle Caille
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, 75005 Paris, France; Université Paris Diderot, Sorbonne Paris Cité, 75013 Paris, France.
| | - Armen Saghatelyan
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada; Department of Psychiatry and Neuroscience, Université Laval, Quebec City, QC G1V 0A6, Canada.
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15
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Becker S. Neurogenesis and pattern separation: time for a divorce. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2016; 8. [PMID: 28026915 DOI: 10.1002/wcs.1427] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 09/09/2016] [Accepted: 09/30/2016] [Indexed: 01/08/2023]
Abstract
The generation of new neurons in the adult mammalian brain has led to numerous theories as to their functional significance. One of the most widely held views is that adult neurogenesis promotes pattern separation, a process by which overlapping patterns of neural activation are mapped to less overlapping representations. While a large body of evidence supports a role for neurogenesis in high interference memory tasks, it does not support the proposed function of neurogenesis in mediating pattern separation. Instead, the adult-generated neurons seem to generate highly overlapping and yet distinct distributed representations for similar events. One way in which these immature, highly plastic, hyperactive neurons may contribute to novel memory formation while avoiding interference is by virtue of their extremely sparse connectivity with incoming perforant path fibers. Another intriguing proposal, awaiting empirical confirmation, is that the young neurons' recruitment into memory formation is gated by a novelty/mismatch mechanism mediated by CA3 or hilar back-projections. Ongoing research into the intriguing link between neurogenesis, stress-related mood disorders, and age-related neurodegeneration may lead to promising neurogenesis-based treatments for this wide range of clinical disorders. WIREs Cogn Sci 2017, 8:e1427. doi: 10.1002/wcs.1427 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Suzanna Becker
- Department of Psychology Neuroscience and Behaviour, McMaster University, Hamilton, Canada
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16
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Gengatharan A, Bammann RR, Saghatelyan A. The Role of Astrocytes in the Generation, Migration, and Integration of New Neurons in the Adult Olfactory Bulb. Front Neurosci 2016; 10:149. [PMID: 27092050 PMCID: PMC4820452 DOI: 10.3389/fnins.2016.00149] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 03/21/2016] [Indexed: 01/10/2023] Open
Abstract
In mammals, new neurons in the adult olfactory bulb originate from a pool of neural stem cells in the subventricular zone of the lateral ventricles. Adult-born cells play an important role in odor information processing by adjusting the neuronal network to changing environmental conditions. Olfactory bulb neurogenesis is supported by several non-neuronal cells. In this review, we focus on the role of astroglial cells in the generation, migration, integration, and survival of new neurons in the adult forebrain. In the subventricular zone, neural stem cells with astrocytic properties display regional and temporal specificity when generating different neuronal subtypes. Non-neurogenic astrocytes contribute to the establishment and maintenance of the neurogenic niche. Neuroblast chains migrate through the rostral migratory stream ensheathed by astrocytic processes. Astrocytes play an important regulatory role in neuroblast migration and also assist in the development of a vasculature scaffold in the migratory stream that is essential for neuroblast migration in the postnatal brain. In the olfactory bulb, astrocytes help to modulate the network through a complex release of cytokines, regulate blood flow, and provide metabolic support, which may promote the integration and survival of new neurons. Astrocytes thus play a pivotal role in various processes of adult olfactory bulb neurogenesis, and it is likely that many other functions of these glial cells will emerge in the near future.
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Affiliation(s)
- Archana Gengatharan
- Cellular Neurobiology Unit, Centre de Recherche de l'Institut Universitaire en Santé Mentale de Québec Quebec, QC, Canada
| | - Rodrigo R Bammann
- Cellular Neurobiology Unit, Centre de Recherche de l'Institut Universitaire en Santé Mentale de Québec Quebec, QC, Canada
| | - Armen Saghatelyan
- Cellular Neurobiology Unit, Centre de Recherche de l'Institut Universitaire en Santé Mentale de QuébecQuebec, QC, Canada; Department of Psychiatry and Neuroscience, Université LavalQuebec, QC, Canada
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17
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McIntyre ABR, Cleland TA. Biophysical constraints on lateral inhibition in the olfactory bulb. J Neurophysiol 2016; 115:2937-49. [PMID: 27009162 DOI: 10.1152/jn.00671.2015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 03/16/2016] [Indexed: 12/26/2022] Open
Abstract
The mitral cells (MCs) of the mammalian olfactory bulb (OB) constitute one of two populations of principal neurons (along with middle/deep tufted cells) that integrate afferent olfactory information with top-down inputs and intrinsic learning and deliver output to downstream olfactory areas. MC activity is regulated in part by inhibition from granule cells, which form reciprocal synapses with MCs along the extents of their lateral dendrites. However, with MC lateral dendrites reaching over 1.5 mm in length in rats, the roles of distal inhibitory synapses pose a quandary. Here, we systematically vary the properties of a MC model to assess the capacity of inhibitory synaptic inputs on lateral dendrites to influence afferent information flow through MCs. Simulations using passivized models with varying dendritic morphologies and synaptic properties demonstrated that, even with unrealistically favorable parameters, passive propagation fails to convey effective inhibitory signals to the soma from distal sources. Additional simulations using an active model exhibiting action potentials, subthreshold oscillations, and a dendritic morphology closely matched to experimental values further confirmed that distal synaptic inputs along the lateral dendrite could not exert physiologically relevant effects on MC spike timing at the soma. Larger synaptic conductances representative of multiple simultaneous inputs were not sufficient to compensate for the decline in signal with distance. Reciprocal synapses on distal MC lateral dendrites may instead serve to maintain a common fast oscillatory clock across the OB by delaying spike propagation within the lateral dendrites themselves.
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Affiliation(s)
- Alexa B R McIntyre
- Tri-Institutional Program in Computational Biology and Medicine, Cornell University, Ithaca, New York; and
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18
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The Role of Adult-Born Neurons in the Constantly Changing Olfactory Bulb Network. Neural Plast 2015; 2016:1614329. [PMID: 26839709 PMCID: PMC4709761 DOI: 10.1155/2016/1614329] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 09/06/2015] [Indexed: 11/17/2022] Open
Abstract
The adult mammalian brain is remarkably plastic and constantly undergoes structurofunctional modifications in response to environmental stimuli. In many regions plasticity is manifested by modifications in the efficacy of existing synaptic connections or synapse formation and elimination. In a few regions, however, plasticity is brought by the addition of new neurons that integrate into established neuronal networks. This type of neuronal plasticity is particularly prominent in the olfactory bulb (OB) where thousands of neuronal progenitors are produced on a daily basis in the subventricular zone (SVZ) and migrate along the rostral migratory stream (RMS) towards the OB. In the OB, these neuronal precursors differentiate into local interneurons, mature, and functionally integrate into the bulbar network by establishing output synapses with principal neurons. Despite continuous progress, it is still not well understood how normal functioning of the OB is preserved in the constantly remodelling bulbar network and what role adult-born neurons play in odor behaviour. In this review we will discuss different levels of morphofunctional plasticity effected by adult-born neurons and their functional role in the adult OB and also highlight the possibility that different subpopulations of adult-born cells may fulfill distinct functions in the OB neuronal network and odor behaviour.
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19
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Garrett L, Zhang J, Zimprich A, Niedermeier KM, Fuchs H, Gailus-Durner V, Hrabě de Angelis M, Vogt Weisenhorn D, Wurst W, Hölter SM. Conditional Reduction of Adult Born Doublecortin-Positive Neurons Reversibly Impairs Selective Behaviors. Front Behav Neurosci 2015; 9:302. [PMID: 26617501 PMCID: PMC4642364 DOI: 10.3389/fnbeh.2015.00302] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 10/29/2015] [Indexed: 11/27/2022] Open
Abstract
Adult neurogenesis occurs in the adult mammalian subventricular zone (SVZ) along the walls of the lateral ventricles and the subgranular zone (SGZ) of the hippocampal dentate gyrus. While a burgeoning body of research implicates adult neurogenesis in olfactory bulb (OB)- and hippocampal-related behaviors, the precise function continues to elude. To further assess the behavioral importance of adult neurogenesis, we herein generated a novel inducible transgenic mouse model of adult neurogenesis reduction where mice with CreERT2 under doublecortin (DCX) promoter control were crossed with mice where diphtheria toxin A (DTA) was driven by the Rosa26 promoter. Activation of DTA, through the administration of tamoxifen (TAM), results in a specific reduction of DCX+ immature neurons in both the hippocampal dentate gyrus and OB. We show that the decrease of DCX+ cells causes impaired social discrimination ability in both young adult (from 3 months) and middle aged (from 10 months) mice. Furthermore, these animals showed an age-independent altered coping behavior in the Forced Swim Test without clear changes in anxiety-related behavior. Notably, these behavior changes were reversible on repopulating the neurogenic zones with DCX+ cells on cessation of the TAM treatment, demonstrating the specificity of this effect. Overall, these results support the notion that adult neurogenesis plays a role in social memory and in stress coping but not necessarily in anxiety-related behavior.
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Affiliation(s)
- Lillian Garrett
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany ; German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany
| | - Jingzhong Zhang
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany ; Max Delbrück Zentrum für Molekulare Medizin Berlin, Germany
| | - Annemarie Zimprich
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany ; German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany
| | - Kristina M Niedermeier
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany ; Technische Universität München Freising-Weihenstephan, Germany
| | - Helmut Fuchs
- German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany
| | - Valerie Gailus-Durner
- German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany
| | - Martin Hrabě de Angelis
- German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany ; Technische Universität München Freising-Weihenstephan, Germany
| | - Daniela Vogt Weisenhorn
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany ; Technische Universität München Freising-Weihenstephan, Germany ; Deutsches Zentrum für Neurodegenerative Erkrankungen e. V. (DZNE) Munich, Germany ; Munich Cluster for Systems Neurology (SyNergy), Ludwig-Maximilians-Universität München Munich, Germany
| | - Sabine M Hölter
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany ; German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health Neuherberg, Germany
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20
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Vangeneugden J, Mazo C, Lepousez G. Commentary: "Posttraining ablation of adult-generated olfactory granule cells degrades odor-reward memories". Front Neurosci 2015; 9:110. [PMID: 25954142 PMCID: PMC4404807 DOI: 10.3389/fnins.2015.00110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 03/15/2015] [Indexed: 11/28/2022] Open
Affiliation(s)
- Joris Vangeneugden
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, European Graduate School of Neuroscience (EURON), Maastricht University Maastricht, Netherlands
| | - Camille Mazo
- Laboratory for Perception and Memory, Department of Neurosciences, Institut Pasteur Paris, France ; Unité Mixte de Recherche 3571, Centre National de la Recherche Scientifique Paris, France
| | - Gabriel Lepousez
- Laboratory for Perception and Memory, Department of Neurosciences, Institut Pasteur Paris, France ; Unité Mixte de Recherche 3571, Centre National de la Recherche Scientifique Paris, France
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21
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Aguilar-Arredondo A, Arias C, Zepeda A. Evaluating the functional state of adult-born neurons in the adult dentate gyrus of the hippocampus: from birth to functional integration. Rev Neurosci 2015; 26:269-79. [DOI: 10.1515/revneuro-2014-0071] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 01/09/2015] [Indexed: 11/15/2022]
Abstract
AbstractHippocampal neurogenesis occurs in the adult brain in various species, including humans. A compelling question that arose when neurogenesis was accepted to occur in the adult dentate gyrus (DG) is whether new neurons become functionally relevant over time, which is key for interpreting their potential contributions to synaptic circuitry. The functional state of adult-born neurons has been evaluated using various methodological approaches, which have, in turn, yielded seemingly conflicting results regarding the timing of maturation and functional integration. Here, we review the contributions of different methodological approaches to addressing the maturation process of adult-born neurons and their functional state, discussing the contributions and limitations of each method. We aim to provide a framework for interpreting results based on the approaches currently used in neuroscience for evaluating functional integration. As shown by the experimental evidence, adult-born neurons are prone to respond from early stages, even when they are not yet fully integrated into circuits. The ongoing integration process for the newborn neurons is characterised by different features. However, they may contribute differently to the network depending on their maturation stage. When combined, the strategies used to date convey a comprehensive view of the functional development of newly born neurons while providing a framework for approaching the critical time at which new neurons become functionally integrated and influence brain function.
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