1
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Jeong M, Jang JH, Oh SJ, Park J, Lee J, Hwang S, Oh YS. Maladaptation of dentate gyrus mossy cells mediates contextual discrimination deficit after traumatic stress. Cell Rep 2024; 43:114000. [PMID: 38527063 DOI: 10.1016/j.celrep.2024.114000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 02/15/2024] [Accepted: 03/10/2024] [Indexed: 03/27/2024] Open
Abstract
Fear overgeneralization is a maladaptive response to traumatic stress that is associated with the inability to discriminate between threat and safety contexts, a hallmark feature of post-traumatic stress disorder (PTSD). However, the neural mechanisms underlying this deficit remain unclear. Here, we show that traumatic stress exposure impairs contextual discrimination between threat and safety contexts in the learned helplessness (LH) model. Mossy cells (MCs) in the dorsal hippocampus are suppressed in response to traumatic stress. Bidirectional manipulation of MC activity in the LH model reveals that MC inhibition is causally linked to impaired contextual discrimination. Mechanistically, MC inhibition increases the number of active granule cells in a given context, significantly overlapping context-specific ensembles. Our study demonstrates that maladaptive inhibition of MCs after traumatic stress is a substantial mechanism underlying fear overgeneralization with contextual discrimination deficit, suggesting a potential therapeutic target for cognitive symptoms of PTSD.
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Affiliation(s)
- Minseok Jeong
- Department of Brain Sciences, Daegu-Gyeongbuk Institute of Science and Technology, Hyeonpung-eup, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Jin-Hyeok Jang
- Department of Brain Sciences, Daegu-Gyeongbuk Institute of Science and Technology, Hyeonpung-eup, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Seo-Jin Oh
- Department of Brain Sciences, Daegu-Gyeongbuk Institute of Science and Technology, Hyeonpung-eup, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Jeongrak Park
- Department of Brain Sciences, Daegu-Gyeongbuk Institute of Science and Technology, Hyeonpung-eup, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Junseop Lee
- Department of Brain Sciences, Daegu-Gyeongbuk Institute of Science and Technology, Hyeonpung-eup, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Sehyeon Hwang
- Department of Brain Sciences, Daegu-Gyeongbuk Institute of Science and Technology, Hyeonpung-eup, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Yong-Seok Oh
- Department of Brain Sciences, Daegu-Gyeongbuk Institute of Science and Technology, Hyeonpung-eup, Dalseong-gun, Daegu 42988, Republic of Korea; Emotion, Cognition & Behavior Research Group, Korea Brain Research Institute, 61 Cheomdan-ro, Daegu 41062, Republic of Korea.
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2
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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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3
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Hung YC, Wu YJ, Chien ME, Lin YT, Tsai CF, Hsu KS. Loss of oxytocin receptors in hilar mossy cells impairs social discrimination. Neurobiol Dis 2023; 187:106311. [PMID: 37769745 DOI: 10.1016/j.nbd.2023.106311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 09/24/2023] [Accepted: 09/25/2023] [Indexed: 10/02/2023] Open
Abstract
Hippocampal oxytocin receptor (OXTR) signaling is crucial for discrimination of social stimuli to guide social recognition, but circuit mechanisms and cell types involved remain incompletely understood. Here, we report a role for OXTR-expressing hilar mossy cells (MCs) of the dentate gyrus in social stimulus discrimination by regulating granule cell (GC) activity. Using a Cre-loxP recombination approach, we found that ablation of Oxtr from MCs impairs discrimination of social, but not object, stimuli in adult male mice. Ablation of MC Oxtr increases spontaneous firing rate of GCs, synaptic excitation to inhibition ratio of MC-to-GC circuit, and GC firing when temporally associated with the lateral perforant path inputs. Using mouse hippocampal slices, we found that bath application of OXTR agonist [Thr4,Gly7]-oxytocin causes membrane depolarization and increases MC firing activity. Optogenetic activation of MC-to-GC circuit ameliorates social discrimination deficit in MC OXTR deficient mice. Together, our results uncover a previously unknown role of MC OXTR signaling for discrimination of social stimuli and delineate a MC-to-GC circuit responsible for social information processing.
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Affiliation(s)
- Yu-Chieh Hung
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
| | - Yi-Jen Wu
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 70457, Taiwan; Department of Neurology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70403, Taiwan
| | - Miao-Er Chien
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 70457, Taiwan
| | - Yu-Ting Lin
- Institute of Systems Neuroscience, College of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Cheng-Fang Tsai
- Department of Physical Medicine and Rehabilitation, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chiayi 60002, Taiwan; Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan.
| | - Kuei-Sen Hsu
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan; Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan.
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4
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Yiu YH, Leibold C. A theory of hippocampal theta correlations accounting for extrinsic and intrinsic sequences. eLife 2023; 12:RP86837. [PMID: 37792453 PMCID: PMC10550285 DOI: 10.7554/elife.86837] [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] [Indexed: 10/05/2023] Open
Abstract
Hippocampal place cell sequences have been hypothesized to serve as diverse purposes as the induction of synaptic plasticity, formation and consolidation of long-term memories, or navigation and planning. During spatial behaviors of rodents, sequential firing of place cells at the theta timescale (known as theta sequences) encodes running trajectories, which can be considered as one-dimensional behavioral sequences of traversed locations. In a two-dimensional space, however, each single location can be visited along arbitrary one-dimensional running trajectories. Thus, a place cell will generally take part in multiple different theta sequences, raising questions about how this two-dimensional topology can be reconciled with the idea of hippocampal sequences underlying memory of (one-dimensional) episodes. Here, we propose a computational model of cornu ammonis 3 (CA3) and dentate gyrus (DG), where sensorimotor input drives the direction-dependent (extrinsic) theta sequences within CA3 reflecting the two-dimensional spatial topology, whereas the intrahippocampal CA3-DG projections concurrently produce intrinsic sequences that are independent of the specific running trajectory. Consistent with experimental data, intrinsic theta sequences are less prominent, but can nevertheless be detected during theta activity, thereby serving as running-direction independent landmark cues. We hypothesize that the intrinsic sequences largely reflect replay and preplay activity during non-theta states.
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Affiliation(s)
- Yuk-Hoi Yiu
- Fakultät für Biologie & Bernstein Center Freiburg Albert-Ludwigs-Universität FreiburgFreiburgGermany
- Graduate School of Systemic Neurosciences, Ludwig-Maximilians-Universität MünchenMunichGermany
| | - Christian Leibold
- Fakultät für Biologie & Bernstein Center Freiburg Albert-Ludwigs-Universität FreiburgFreiburgGermany
- BrainLinks-BrainTools, Albert-Ludwigs-Universität FreiburgFreiburgGermany
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5
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Kim SY, Lim W. Disynaptic effect of hilar cells on pattern separation in a spiking neural network of hippocampal dentate gyrus. Cogn Neurodyn 2022; 16:1427-1447. [PMID: 36408073 PMCID: PMC9666645 DOI: 10.1007/s11571-022-09797-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 01/25/2022] [Accepted: 03/02/2022] [Indexed: 11/28/2022] Open
Abstract
We study the disynaptic effect of the hilar cells on pattern separation in a spiking neural network of the hippocampal dentate gyrus (DG). The principal granule cells (GCs) in the DG perform pattern separation, transforming similar input patterns into less-similar output patterns. In our DG network, the hilus consists of excitatory mossy cells (MCs) and inhibitory HIPP (hilar perforant path-associated) cells. Here, we consider the disynaptic effects of the MCs and the HIPP cells on the GCs, mediated by the inhibitory basket cells (BCs) in the granular layer; MC → BC → GC and HIPP → BC → GC. The MCs provide disynaptic inhibitory input (mediated by the intermediate BCs) to the GCs, which decreases the firing activity of the GCs. On the other hand, the HIPP cells disinhibit the intermediate BCs, which leads to increasing the firing activity of the GCs. In this way, the disynaptic effects of the MCs and the HIPP cells are opposite. We investigate change in the pattern separation efficacy by varying the synaptic strength K ( BC , X ) [from the pre-synaptic X (= MC or HIPP) to the post-synaptic BC]. Thus, sparsity for the firing activity of the GCs is found to improve the efficacy of pattern separation, and hence the disynaptic effects of the MCs and the HIPP cells on the pattern separation become opposite ones. In the combined case when simultaneously changing both K ( BC , MC ) and K ( BC , HIPP ) , as a result of balance between the two competing disynaptic effects of the MCs and the HIPP cells, the efficacy of pattern separation is found to become the highest at their original default values where the activation degree of the GCs is the lowest. We also note that, while the GCs perform pattern separation, sparsely synchronized rhythm is found to appear in the population of the GCs. Hence, we examine quantitative association between population and individual firing behaviors in the sparsely synchronized rhythm and pattern separation. They are found to be strongly correlated. Consequently, the better the population and individual firing behaviors in the sparsely synchronized rhythm are, the more pattern separation efficacy becomes enhanced.
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Affiliation(s)
- Sang-Yoon Kim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu, 42411 Korea
| | - Woochang Lim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu, 42411 Korea
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6
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Huang PH, Yang TY, Yeh CW, Huang SM, Chang HC, Hung YF, Chu WC, Cho KH, Lu TP, Kuo PH, Lee LJ, Kuo LW, Lien CC, Cheng HJ. Involvement of a BH3-only apoptosis sensitizer gene Blm-s in hippocampus-mediated mood control. Transl Psychiatry 2022; 12:411. [PMID: 36163151 PMCID: PMC9512807 DOI: 10.1038/s41398-022-02184-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 09/07/2022] [Accepted: 09/13/2022] [Indexed: 11/18/2022] Open
Abstract
Mood disorders are an important public health issue and recent advances in genomic studies have indicated that molecules involved in neurodevelopment are causally related to mood disorders. BLM-s (BCL-2-like molecule, small transcript isoform), a BH3-only proapoptotic BCL-2 family member, mediates apoptosis of postmitotic immature neurons during embryonic cortical development, but its role in the adult brain is unknown. To better understand the physiological role of Blm-s gene in vivo, we generated a Blm-s-knockout (Blm-s-/-) mouse. The Blm-s-/- mice breed normally and exhibit grossly normal development. However, global depletion of Blm-s is highly associated with depression- and anxiety-related behaviors in adult mutant mice with intact learning and memory capacity. Functional magnetic resonance imaging of adult Blm-s-/- mice reveals reduced connectivity mainly in the ventral dentate gyrus (vDG) of the hippocampus with no alteration in the dorsal DG connectivity and in total hippocampal volume. At the cellular level, BLM-s is expressed in DG granule cells (GCs), and Blm-s-/- mice show reduced dendritic complexity and decreased spine density in mature GCs. Electrophysiology study uncovers that mature vGCs in adult Blm-s-/- DG are intrinsically more excitable. Interestingly, certain genetic variants of the human Blm homologue gene (VPS50) are significantly associated with depression traits from publicly resourced UK Biobank data. Taken together, BLM-s is required for the hippocampal mood control function. Loss of BLM-s causes abnormality in the electrophysiology and morphology of GCs and a disrupted vDG neural network, which could underlie Blm-s-null-associated anxiety and depression.
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Affiliation(s)
- Pei-Hsin Huang
- Graduate Institute of Pathology, College of Medicine, National Taiwan University, 100, Taipei, Taiwan. .,Department of Pathology, National Taiwan University Hospital, 100, Taipei, Taiwan.
| | - Tsung-Ying Yang
- Graduate Institute of Pathology, College of Medicine, National Taiwan University, 100, Taipei, Taiwan
| | - Chia-Wei Yeh
- Institute of Neuroscience, College of Life Sciences, National Yang Ming Chiao Tung University, 112, Taipei, Taiwan
| | - Sheng-Min Huang
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, 350, Miaoli, Taiwan
| | - Ho-Ching Chang
- Institute of Molecular Biology, Academia Sinica, 115, Taipei, Taiwan
| | - Yun-Fen Hung
- Institute of Molecular Biology, Academia Sinica, 115, Taipei, Taiwan
| | - Wen-Chia Chu
- Graduate Institute of Pathology, College of Medicine, National Taiwan University, 100, Taipei, Taiwan
| | - Kuan-Hung Cho
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, 350, Miaoli, Taiwan
| | - Tzu-Pin Lu
- Department of Public Health & Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, 100, Taipei, Taiwan
| | - Po-Hsiu Kuo
- Department of Public Health & Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, 100, Taipei, Taiwan.,Department of Psychiatry, National Taiwan University Hospital, 100, Taipei, Taiwan
| | - Li-Jen Lee
- Graduate Institute of Anatomy and Cell Biology, College of Medicine, National Taiwan University, 100, Taipei, Taiwan.,Institute of Brain and Mind Sciences, College of Medicine, National Taiwan University, 100, Taipei, Taiwan
| | - Li-Wei Kuo
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, 350, Miaoli, Taiwan.,Institute of Medical Device and Imaging, College of Medicine, National Taiwan University, 100, Taipei, Taiwan
| | - Cheng-Chang Lien
- Institute of Neuroscience, College of Life Sciences, National Yang Ming Chiao Tung University, 112, Taipei, Taiwan.,Brain Research Center, National Yang Ming Chiao Tung University, 112, Taipei, Taiwan
| | - Hwai-Jong Cheng
- Institute of Molecular Biology, Academia Sinica, 115, Taipei, Taiwan
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7
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Caputi A, Liu X, Fuchs EC, Liu YC, Monyer H. Medial entorhinal cortex commissural input regulates the activity of spatially and object-tuned cells contributing to episodic memory. Neuron 2022; 110:3389-3405.e7. [PMID: 36084654 DOI: 10.1016/j.neuron.2022.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 07/14/2022] [Accepted: 08/08/2022] [Indexed: 10/14/2022]
Abstract
Extensive interhemispheric projections connect many homotopic brain regions, including the hippocampal formation, but little is known as to how information transfer affects the functions supported by the target area. Here, we studied whether the commissural projections connecting the medial entorhinal cortices contribute to spatial coding, object coding, and memory. We demonstrate that input from the contralateral medial entorhinal cortex targets all major cell types in the superficial medial entorhinal cortex, modulating their firing rate. Notably, a fraction of responsive cells displayed object tuning and exhibited a reduction in their firing rate upon the inhibition of commissural input. In line with this finding are behavioral results that revealed the contribution of commissural input to episodic-like memory retrieval.
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Affiliation(s)
- Antonio Caputi
- Department of Clinical Neurobiology at the Medical Faculty of the Heidelberg University and of the German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Xinghua Liu
- Department of Clinical Neurobiology at the Medical Faculty of the Heidelberg University and of the German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Elke C Fuchs
- Department of Clinical Neurobiology at the Medical Faculty of the Heidelberg University and of the German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Yu-Chao Liu
- Department of Clinical Neurobiology at the Medical Faculty of the Heidelberg University and of the German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Hannah Monyer
- Department of Clinical Neurobiology at the Medical Faculty of the Heidelberg University and of the German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
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8
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Perrenoud Q, Leclerc C, Geoffroy H, Vitalis T, Richetin K, Rampon C, Gallopin T. Molecular and electrophysiological features of GABAergic neurons in the dentate gyrus reveal limited homology with cortical interneurons. PLoS One 2022; 17:e0270981. [PMID: 35802727 PMCID: PMC9269967 DOI: 10.1371/journal.pone.0270981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 06/21/2022] [Indexed: 11/18/2022] Open
Abstract
GABAergic interneurons tend to diversify into similar classes across telencephalic regions. However, it remains unclear whether the electrophysiological and molecular properties commonly used to define these classes are discriminant in the hilus of the dentate gyrus. Here, using patch-clamp combined with single cell RT-PCR, we compare the relevance of commonly used electrophysiological and molecular features for the clustering of GABAergic interneurons sampled from the mouse hilus and primary sensory cortex. While unsupervised clustering groups cortical interneurons into well-established classes, it fails to provide a convincing partition of hilar interneurons. Statistical analysis based on resampling indicates that hilar and cortical GABAergic interneurons share limited homology. While our results do not invalidate the use of classical molecular marker in the hilus, they indicate that classes of hilar interneurons defined by the expression of molecular markers do not exhibit strongly discriminating electrophysiological properties.
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Affiliation(s)
- Quentin Perrenoud
- Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
| | - Clémence Leclerc
- Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, France
| | - Hélène Geoffroy
- Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
| | - Tania Vitalis
- Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
| | - Kevin Richetin
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, France
| | - Claire Rampon
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse; CNRS, UPS, France
| | - Thierry Gallopin
- Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, Paris, France
- * E-mail:
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9
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Abdulmajeed WI, Wang KY, Wu JW, Ajibola MI, Cheng IHJ, Lien CC. Connectivity and synaptic features of hilar mossy cells and their effects on granule cell activity along the hippocampal longitudinal axis. J Physiol 2022; 600:3355-3381. [PMID: 35671148 DOI: 10.1113/jp282804] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/01/2022] [Indexed: 11/08/2022] Open
Abstract
The hippocampus is an elongated brain structure which runs along a ventral-to-dorsal axis in rodents, corresponding to the anterior-to-posterior axis in humans. A glutamatergic cell type in the dentate gyrus (DG), the mossy cells (MCs), establishes extensive excitatory collateral connections with the DG principal cells, the granule cells (GCs), and inhibitory interneurons in both hippocampal hemispheres along the longitudinal axis. Although coupling of two physically separated GC populations via long-axis projecting MCs is instrumental for information processing, the connectivity and synaptic features of MCs along the longitudinal axis are poorly defined. Here, using channelrhodopsin-2 assisted circuit mapping, we showed that MC excitation results in a low synaptic excitation-inhibition (E/I) balance in the intralamellar (local) GCs, but a high synaptic E/I balance in the translamellar (distant) ones. In agreement with the differential E/I balance along the ventrodorsal axis, activation of MCs either enhances or suppresses the local GC response to the cortical input, but primarily promotes the distant GC activation. Moreover, activation of MCs enhances the spike timing precision of the local GCs, but not that of the distant ones. Collectively, these findings suggest that MCs differentially regulate the local and distant GC activity through distinct synaptic mechanisms. KEY POINTS: Hippocampal mossy cell (MC) pathways differentially regulate granule cell (GC) activity along the longitudinal axis. MCs mediate a low excitation-inhibition balance in intralamellar (local) GCs, but a high excitation-inhibition balance in translamellar (distant) GCs. MCs enhance the spiking precision of local GCs, but not distant GCs. MCs either promote or suppress local GC activity, but primarily promote distant GC activation.
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Affiliation(s)
- Wahab Imam Abdulmajeed
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, Academia Sinica, Taipei, Taiwan.,Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, University of Ilorin, Ilorin, Nigeria
| | - Kai-Yi Wang
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Jei-Wei Wu
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Musa Iyiola Ajibola
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, Academia Sinica, Taipei, Taiwan.,Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Irene Han-Juo Cheng
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, Academia Sinica, Taipei, Taiwan.,Institute of Brain Science, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Cheng-Chang Lien
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, Academia Sinica, Taipei, Taiwan.,Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
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10
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Yen TY, Huang X, MacLaren DAA, Schlesiger MI, Monyer H, Lien CC. Inhibitory projections connecting the dentate gyri in the two hemispheres support spatial and contextual memory. Cell Rep 2022; 39:110831. [PMID: 35584671 DOI: 10.1016/j.celrep.2022.110831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 11/17/2021] [Accepted: 04/27/2022] [Indexed: 12/01/2022] Open
Abstract
The dentate gyrus (DG) receives substantial input from the homologous brain area of the contralateral hemisphere. This input is by and large excitatory. Viral-tracing experiments provided anatomical evidence for the existence of GABAergic connectivity between the two DGs, but the function of these projections has remained elusive. Combining electrophysiological and optogenetic approaches, we demonstrate that somatostatin-expressing contralateral DG (SOM+ cDG)-projecting neurons preferentially engage dendrite-targeting interneurons over principal neurons. Single-unit recordings from freely moving mice reveal that optogenetic stimulation of SOM+ cDG projections modulates the activity of GABAergic neurons and principal neurons over multiple timescales. Importantly, we demonstrate that optogenetic silencing of SOM+ cDG projections during spatial memory encoding, but not during memory retrieval, results in compromised DG-dependent memory. Moreover, optogenetic stimulation of SOM+ cDG projections is sufficient to disrupt contextual memory recall. Collectively, our findings reveal that SOM+ long-range projections mediate inter-DG inhibition and contribute to learning and memory.
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Affiliation(s)
- Ting-Yun Yen
- Taiwan International Graduate Program in Molecular Medicine, National Yang Ming Chiao Tung University and Academia Sinica, Taipei, Taiwan; Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei 112, Taiwan; Department of Clinical Neurobiology at the Medical Faculty of Heidelberg University and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Xu Huang
- Department of Clinical Neurobiology at the Medical Faculty of Heidelberg University and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Duncan Archibald Allan MacLaren
- Department of Clinical Neurobiology at the Medical Faculty of Heidelberg University and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Magdalene Isabell Schlesiger
- Department of Clinical Neurobiology at the Medical Faculty of Heidelberg University and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Hannah Monyer
- Department of Clinical Neurobiology at the Medical Faculty of Heidelberg University and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
| | - Cheng-Chang Lien
- Taiwan International Graduate Program in Molecular Medicine, National Yang Ming Chiao Tung University and Academia Sinica, Taipei, Taiwan; Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei 112, Taiwan.
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11
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Kim SY, Lim W. Dynamical origin for winner-take-all competition in a biological network of the hippocampal dentate gyrus. Phys Rev E 2022; 105:014418. [PMID: 35193268 DOI: 10.1103/physreve.105.014418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
We consider a biological network of the hippocampal dentate gyrus (DG). Computational models suggest that the DG would be a preprocessor for pattern separation (i.e., a process transforming a set of similar input patterns into distinct nonoverlapping output patterns) which could facilitate pattern storage and retrieval in the CA3 area of the hippocampus. The main encoding cells in the DG are the granule cells (GCs) which receive the input from the entorhinal cortex (EC) and send their output to the CA3. We note that the activation degree of GCs is very low (∼5%). This sparsity has been thought to enhance the pattern separation. We investigate the dynamical origin for winner-take-all (WTA) competition which leads to sparse activation of the GCs. The whole GCs are grouped into lamellar clusters. In each cluster, there is one inhibitory (I) basket cell (BC) along with excitatory (E) GCs. There are three kinds of external inputs into the GCs: the direct excitatory EC input; the indirect feedforward inhibitory EC input, mediated by the HIPP (hilar perforant path-associated) cells; and the excitatory input from the hilar mossy cells (MCs). The firing activities of the GCs are determined via competition between the external E and I inputs. The E-I conductance ratio R_{E-I}^{(con)}^{*} (given by the time average of the ratio of the external E to I conductances) may represent well the degree of such external E-I input competition. It is thus found that GCs become active when their R_{E-I}^{(con)}^{*} is larger than a threshold R_{th}^{*}, and then the mean firing rates of the active GCs are strongly correlated with R_{E-I}^{(con)}^{*}. In each cluster, the feedback inhibition from the BC may select the winner GCs. GCs with larger R_{E-I}^{(con)}^{*} than the threshold R_{th}^{*} survive, and they become winners; all the other GCs with smaller R_{E-I}^{(con)}^{*} become silent. In this way, WTA competition occurs via competition between the firing activity of the GCs and the feedback inhibition from the BC in each cluster. Finally, we also study the effects of MC death and adult-born immature GCs on the WTA competition.
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Affiliation(s)
- Sang-Yoon Kim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu 42411, Korea
| | - Woochang Lim
- Institute for Computational Neuroscience and Department of Science Education, Daegu National University of Education, Daegu 42411, Korea
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12
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Vasu SO, Kaphzan H. Calcium channels control tDCS-induced spontaneous vesicle release from axon terminals. Brain Stimul 2022; 15:270-282. [DOI: 10.1016/j.brs.2022.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 01/06/2022] [Accepted: 01/06/2022] [Indexed: 12/29/2022] Open
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13
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Hao S, Wang Q, Tang B, Wu Z, Yang T, Tang J. CDKL5 Deficiency Augments Inhibitory Input into the Dentate Gyrus That Can Be Reversed by Deep Brain Stimulation. J Neurosci 2021; 41:9031-9046. [PMID: 34544833 PMCID: PMC8549531 DOI: 10.1523/jneurosci.1010-21.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 07/16/2021] [Accepted: 08/16/2021] [Indexed: 12/12/2022] Open
Abstract
Cognitive impairment is a core feature of cyclin-dependent kinase-like 5 (CDKL5) deficiency, a neurodevelopmental disorder characterized by early epileptic seizures, intellectual disability, and autistic behaviors. Although loss of CDKL5 affects a number of molecular pathways, very little has been discovered about the physiological effects of these changes on the neural circuitry. We therefore studied synaptic plasticity and local circuit activity in the dentate gyrus of both Cdkl5-/y and Cdkl5+/- mutant mice. We found that CDKL5 haploinsufficiency in both male and female mice impairs hippocampus-dependent learning and memory in multiple tasks. In vivo, loss of CDKL5 reduced LTP of the perforant path to the dentate gyrus and augmented feedforward inhibition in this pathway; ex vivo experiments confirmed that excitatory/inhibitory input into the dentate gyrus is skewed toward inhibition. Injecting the GABAergic antagonist gabazine into the dentate improved contextual fear memory in Cdkl5-/y mice. Finally, chronic forniceal deep brain stimulation rescued hippocampal memory deficits, restored synaptic plasticity, and relieved feedforward inhibition in Cdkl5+/- mice. These results indicate that CDKL5 is important for maintaining proper dentate excitatory/inhibitory balance, with consequences for hippocampal memory.SIGNIFICANCE STATEMENT Cognitive impairment is a core feature of cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder. Although CDKL5 deficiency has been found to affect a number of molecular pathways, little is known about its physiological effects on the neural circuitry. We find that CDKL5 loss reduces hippocampal synaptic plasticity and augments feedforward inhibition in the perforant path to the dentate gyrus in vivo in Cdkl5 mutant mice. Chronic forniceal deep brain stimulation rescued hippocampal memory deficits, restored synaptic plasticity, and relieved feedforward inhibition in Cdkl5+/- mice, as it had previously done with Rett syndrome mice, suggesting that such stimulation may be useful for other neurodevelopmental disorders.
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Affiliation(s)
- Shuang Hao
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas 77030
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030
| | - Qi Wang
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas 77030
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030
| | - Bin Tang
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas 77030
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030
| | - Zhenyu Wu
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas 77030
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030
| | - Tingting Yang
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas 77030
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030
- Department of Neurology, People's Hospital of Guizhou Province, Guiyang, 560000, China
| | - Jianrong Tang
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas 77030
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030
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14
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Wang KY, Wu JW, Cheng JK, Chen CC, Wong WY, Averkin RG, Tamás G, Nakazawa K, Lien CC. Elevation of hilar mossy cell activity suppresses hippocampal excitability and avoidance behavior. Cell Rep 2021; 36:109702. [PMID: 34525354 DOI: 10.1016/j.celrep.2021.109702] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 07/09/2021] [Accepted: 08/20/2021] [Indexed: 12/30/2022] Open
Abstract
Modulation of hippocampal dentate gyrus (DG) excitability regulates anxiety. In the DG, glutamatergic mossy cells (MCs) receive the excitatory drive from principal granule cells (GCs) and mediate the feedback excitation and inhibition of GCs. However, the circuit mechanism by which MCs regulate anxiety-related information routing through hippocampal circuits remains unclear. Moreover, the correlation between MC activity and anxiety states is unclear. In this study, we first demonstrate, by means of calcium fiber photometry, that MC activity in the ventral hippocampus (vHPC) of mice increases while they explore anxiogenic environments. Next, juxtacellular recordings reveal that optogenetic activation of MCs preferentially recruits GABAergic neurons, thereby suppressing GCs and ventral CA1 neurons. Finally, chemogenetic excitation of MCs in the vHPC reduces avoidance behaviors in both healthy and anxious mice. These results not only indicate an anxiolytic role of MCs but also suggest that MCs may be a potential therapeutic target for anxiety disorders.
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Affiliation(s)
- Kai-Yi Wang
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan
| | - Jei-Wei Wu
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan
| | - Jen-Kun Cheng
- Department of Medicine, Mackay Medical College, New Taipei 252, Taiwan; Department of Anesthesiology, Mackay Memorial Hospital, Taipei 104, Taiwan
| | | | - Wai-Yi Wong
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan
| | - Robert G Averkin
- ELKH-SZTE Research Group for Cortical Microcircuits, Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, Szeged 6726, Hungary
| | - Gábor Tamás
- ELKH-SZTE Research Group for Cortical Microcircuits, Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, Szeged 6726, Hungary
| | - Kazu Nakazawa
- Department of Neuroscience, Southern Research, Birmingham, AL 35205, USA; Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Cheng-Chang Lien
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan; Brain Research Center, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan.
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15
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Ma Y, Bayguinov PO, McMahon SM, Scharfman HE, Jackson MB. Direct synaptic excitation between hilar mossy cells revealed with a targeted voltage sensor. Hippocampus 2021; 31:1215-1232. [PMID: 34478219 DOI: 10.1002/hipo.23386] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 08/09/2021] [Accepted: 08/21/2021] [Indexed: 12/18/2022]
Abstract
The dentate gyrus not only gates the flow of information into the hippocampus, it also integrates and processes this information. Mossy cells (MCs) are a major type of excitatory neuron strategically located in the hilus of the dentate gyrus where they can contribute to this processing through networks of synapses with inhibitory neurons and dentate granule cells. Some prior work has suggested that MCs can form excitatory synapses with other MCs, but the role of these synapses in the network activity of the dentate gyrus has received little attention. Here, we investigated synaptic inputs to MCs in mouse hippocampal slices using a genetically encoded hybrid voltage sensor (hVOS) targeted to MCs by Cre-lox technology. This enabled optical recording of voltage changes from multiple MCs simultaneously. Stimulating granule cells and CA3 pyramidal cells activated well-established inputs to MCs and elicited synaptic responses as expected. However, the weak blockade of MC responses to granule cell layer stimulation by DCG-IV raised the possibility of another source of excitation. To evaluate synapses between MCs as this source, single MCs were stimulated focally. Stimulation of one MC above its action potential threshold evoked depolarizing responses in neighboring MCs that depended on glutamate receptors. Short latency responses of MCs to other MCs did not depend on release from granule cell axons. However, granule cells did contribute to the longer latency responses of MCs to stimulation of other MCs. Thus, MCs transmit their activity to other MCs both through direct synaptic coupling and through polysynaptic coupling with dentate granule cells. MC-MC synapses can redistribute information entering the dentate gyrus and thus shape and modulate the electrical activity underlying hippocampal functions such as navigation and memory, as well as excessive excitation during seizures.
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Affiliation(s)
- Yihe Ma
- Department of Neuroscience, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Peter O Bayguinov
- Washington University Center for Cellular Imaging, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Shane M McMahon
- Department of Neuroscience, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Helen E Scharfman
- New York University Langone Health and the Nathan Kline Institute for Psychiatric Research, Orangeburg, New Jersey, USA
| | - Meyer B Jackson
- Department of Neuroscience, University of Wisconsin-Madison, Madison, Wisconsin, USA
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16
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Modeling intrahippocampal effects of anterior hippocampal hyperactivity relevant to schizophrenia using chemogenetic excitation of long axis-projecting mossy cells in the mouse dentate gyrus. BIOLOGICAL PSYCHIATRY GLOBAL OPEN SCIENCE 2021; 1:101-111. [PMID: 34414387 PMCID: PMC8372626 DOI: 10.1016/j.bpsgos.2021.04.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Background The anterior hippocampus of individuals with early psychosis or schizophrenia is hyperactive, as is the ventral hippocampus in many rodent models for schizophrenia risk. Mossy cells (MCs) of the ventral dentate gyrus (DG) densely project in the hippocampal long axis, targeting both dorsal DG granule cells and inhibitory interneurons. MCs are responsive to stimulation throughout hippocampal subfields and thus may be suited to detect hyperactivity in areas where it originates such as CA1. Here, we tested the hypothesis that hyperactivation of ventral MCs activates dorsal DG granule cells to influence dorsal hippocampal function. Methods In CD-1 mice, we targeted dorsal DG-projecting ventral MCs using an adeno-associated virus intersectional strategy. In vivo fiber photometry recording of ventral MCs was performed during exploratory behaviors. We used excitatory chemogenetic constructs to test the effects of ventral MC hyperactivation on long-term spatial memory during an object location memory task. Results Photometry revealed that ventral MCs were activated during exploratory rearing. Ventral MCs made functional monosynaptic inputs to dorsal DG granule cells, and chemogenetic activation of ventral MCs modestly increased activity of dorsal DG granule cells measured by c-Fos. Finally, chemogenetic activation of ventral MCs during the training phase of an object location memory task impaired test performance 24 hours later, without effects on locomotion or object exploration. Conclusions These data suggest that ventral MC activation can directly excite dorsal granule cells and interfere with dorsal DG function, supporting future study of their in vivo activity in animal models for schizophrenia featuring ventral hyperactivity.
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17
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Wei YT, Wu JW, Yeh CW, Shen HC, Wu KP, Vida I, Lien CC. Morpho-physiological properties and connectivity of vasoactive intestinal polypeptide-expressing interneurons in the mouse hippocampal dentate gyrus. J Comp Neurol 2021; 529:2658-2675. [PMID: 33484471 DOI: 10.1002/cne.25116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 01/16/2021] [Accepted: 01/17/2021] [Indexed: 11/08/2022]
Abstract
The hippocampus is a key brain structure for cognitive and emotional functions. Among the hippocampal subregions, the dentate gyrus (DG) is the first station that receives multimodal sensory information from the cortex. Local-circuit inhibitory GABAergic interneurons (INs) regulate the excitation-inhibition balance in the DG principal neurons (PNs) and therefore are critical for information processing. Similar to PNs, GABAergic INs also receive distinct inhibitory inputs. Among various classes of INs, vasoactive intestinal polypeptide-expressing (VIP+ ) INs preferentially target other INs in several brain regions and thereby directly modulate the GABAergic system. However, the morpho-physiological characteristics and postsynaptic targets of VIP+ INs in the DG are poorly understood. Here, we report that VIP+ INs in the mouse DG are highly heterogeneous based on their morpho-physiological characteristics. In approximately two-thirds of morphologically reconstructed cells, their axons ramify in the hilus. The remaining cells project their axons exclusively to the molecular layer (15%), to both the molecular layer and hilus (10%), or throughout the entire DG layers (8%). Generally, VIP+ INs display variable intrinsic properties and discharge patterns without clear correlation with their morphologies. Finally, VIP+ INs are recruited with a long latency in response to theta-band cortical inputs and preferentially innervate GABAergic INs over glutamatergic PNs. In summary, VIP+ INs in the DG are composed of highly diverse subpopulations and control the DG output via disinhibition.
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Affiliation(s)
- Yu-Ting Wei
- Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan
| | - Jei-Wei Wu
- Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan
| | - Chia-Wei Yeh
- Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan
| | - Hung-Chang Shen
- Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan
| | - Kun-Pin Wu
- Institute of Biomedical Informatics, National Yang-Ming University, Taipei, Taiwan
| | - Imre Vida
- Institute for Integrative Neuroanatomy, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Cheng-Chang Lien
- Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan.,Brain Research Center, National Yang-Ming University, Taipei, Taiwan
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18
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Fredes F, Shigemoto R. The role of hippocampal mossy cells in novelty detection. Neurobiol Learn Mem 2021; 183:107486. [PMID: 34214666 DOI: 10.1016/j.nlm.2021.107486] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/29/2021] [Accepted: 06/24/2021] [Indexed: 10/21/2022]
Abstract
At the encounter with a novel environment, contextual memory formation is greatly enhanced, accompanied with increased arousal and active exploration. Although this phenomenon has been widely observed in animal and human daily life, how the novelty in the environment is detected and contributes to contextual memory formation has lately started to be unveiled. The hippocampus has been studied for many decades for its largely known roles in encoding spatial memory, and a growing body of evidence indicates a differential involvement of dorsal and ventral hippocampal divisions in novelty detection. In this brief review article, we discuss the recent findings of the role of mossy cells in the ventral hippocampal moiety in novelty detection and put them in perspective with other novelty-related pathways in the hippocampus. We propose a mechanism for novelty-driven memory acquisition in the dentate gyrus by the direct projection of ventral mossy cells to dorsal dentate granule cells. By this projection, the ventral hippocampus sends novelty signals to the dorsal hippocampus, opening a gate for memory encoding in dentate granule cells based on information coming from the entorhinal cortex. We conclude that, contrary to the presently accepted functional independence, the dorsal and ventral hippocampi cooperate to link the novelty and contextual information, and this dorso-ventral interaction is crucial for the novelty-dependent memory formation.
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Affiliation(s)
- Felipe Fredes
- Department of Biomedicine, Aarhus University, Ole Worms Ale 6, Building 1182, 8000 Aarhus C, Denmark
| | - Ryuichi Shigemoto
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, Klosterneuburg 3400, Austria
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19
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Vcp Overexpression and Leucine Supplementation Increase Protein Synthesis and Improve Fear Memory and Social Interaction of Nf1 Mutant Mice. Cell Rep 2021; 31:107835. [PMID: 32610136 DOI: 10.1016/j.celrep.2020.107835] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 03/25/2020] [Accepted: 06/08/2020] [Indexed: 11/22/2022] Open
Abstract
Neurofibromatosis type 1 (NF1) is a dominant genetic disorder manifesting, in part, as cognitive defects. Previous study indicated that neurofibromin (NF1 protein) interacts with valosin-containing protein (VCP)/P97 to control dendritic spine formation, but the mechanism is unknown. Here, using Nf1+/- mice and transgenic mice overexpressing wild-type Vcp/p97, we demonstrate that neurofibromin acts with VCP to control endoplasmic reticulum (ER) formation and consequent protein synthesis and regulates dendritic spine formation, thereby modulating contextual fear memory and social interaction. To validate the role of protein synthesis, we perform leucine supplementation in vitro and in vivo. Our results suggest that leucine can effectively enter the brain and increase protein synthesis and dendritic spine density of Nf1+/- neurons. Contextual memory and social behavior of Nf1+/- mice are also restored by leucine supplementation. Our study suggests that the "ER-protein synthesis" pathway downstream of neurofibromin and VCP is a critical regulator of dendritic spinogenesis and brain function.
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20
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Houser CR, Peng Z, Wei X, Huang CS, Mody I. Mossy Cells in the Dorsal and Ventral Dentate Gyrus Differ in Their Patterns of Axonal Projections. J Neurosci 2021; 41:991-1004. [PMID: 33268544 PMCID: PMC7880284 DOI: 10.1523/jneurosci.2455-20.2020] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/08/2020] [Accepted: 11/20/2020] [Indexed: 01/22/2023] Open
Abstract
Mossy cells (MCs) of the dentate gyrus (DG) are a major group of excitatory hilar neurons that are important for regulating activity of dentate granule cells. MCs are particularly intriguing because of their extensive longitudinal connections within the DG. It has generally been assumed that MCs in the dorsal and ventral DG have similar patterns of termination in the inner one-third of the dentate molecular layer. Here, we demonstrate that axonal projections of MCs in these two regions are considerably different. MCs in dorsal and ventral regions were labeled selectively with Cre-dependent eYFP or mCherry, using two transgenic mouse lines (including both sexes) that express Cre-recombinase in MCs. At four to six weeks following unilateral labeling of MCs in the ventral DG, a dense band of fibers was present in the inner one-fourth of the molecular layer and extended bilaterally throughout the rostral-caudal extent of the DG, replicating the expected distribution of MC axons. In contrast, following labeling of MCs in the dorsal DG, the projections were more diffusely distributed. At the level of transfection, fibers were present in the inner molecular layer, but they progressively expanded into the middle molecular layer and, most ventrally, formed a distinct band in this region. Optical stimulation of these caudal fibers expressing ChR2 demonstrated robust EPSCs in ipsilateral granule cells and enhanced the effects of perforant path stimulation in the ventral DG. These findings suggest that MCs in the dorsal and ventral DG differ in the distribution of their axonal projections and possibly their function.SIGNIFICANCE STATEMENT Mossy cells (MCs), a major cell type in the hilus of the dentate gyrus (DG), are unique in providing extensive longitudinal and commissural projections throughout the DG. Although it has been assumed that all MCs have similar patterns of termination in the inner molecular layer of the DG, we discovered that the axonal projections of dorsal and ventral MCs differ. While ventral MC projections exhibit the classical pattern, with dense innervation in the inner molecular layer, dorsal MCs have a more diffuse distribution and expand into the middle molecular layer where they overlap and interact with innervation from the perforant path. These distinct locations and patterns of axonal projections suggest that dorsal and ventral MCs may have different functional roles.
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Affiliation(s)
- Carolyn R Houser
- Department of Neurobiology
- Brain Research Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California 90095
| | | | | | | | - Istvan Mody
- Department of Neurology
- Brain Research Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California 90095
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21
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Bidirectional Regulation of Cognitive and Anxiety-like Behaviors by Dentate Gyrus Mossy Cells in Male and Female Mice. J Neurosci 2021; 41:2475-2495. [PMID: 33472828 DOI: 10.1523/jneurosci.1724-20.2021] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 12/04/2020] [Accepted: 01/04/2021] [Indexed: 02/08/2023] Open
Abstract
The dentate gyrus (DG) of the hippocampus is important for cognition and behavior. However, the circuits underlying these functions are unclear. DG mossy cells (MCs) are potentially important because of their excitatory synapses on the primary cell type, granule cells (GCs). However, MCs also activate GABAergic neurons, which inhibit GCs. We used viral delivery of designer receptors exclusively activated by designer drugs (DREADDs) in mice to implement a gain- and loss-of-function study of MCs in diverse behaviors. Using this approach, manipulations of MCs could bidirectionally regulate behavior. The results suggest that inhibiting MCs can reduce anxiety-like behavior and improve cognitive performance. However, not all cognitive or anxiety-related behaviors were influenced, suggesting specific roles of MCs in some, but not all, types of cognition and anxiety. Notably, several behaviors showed sex-specific effects, with females often showing more pronounced effects than the males. We also used the immediate early gene c-Fos to address whether DREADDs bidirectionally regulated MC or GC activity. We confirmed excitatory DREADDs increased MC c-Fos. However, there was no change in GC c-Fos, consistent with MC activation leading to GABAergic inhibition of GCs. In contrast, inhibitory DREADDs led to a large increase in GC c-Fos, consistent with a reduction in MC excitation of GABAergic neurons, and reduced inhibition of GCs. Together, these results suggest that MCs regulate anxiety and cognition in specific ways. We also raise the possibility that cognitive performance may be improved by reducing anxiety.SIGNIFICANCE STATEMENT The dentate gyrus (DG) has many important cognitive roles as well as being associated with affective behavior. This study addressed how a glutamatergic DG cell type called mossy cells (MCs) contributes to diverse behaviors, which is timely because it is known that MCs regulate the activity of the primary DG cell type, granule cells (GCs), but how MC activity influences behavior is unclear. We show, surprisingly, that activating MCs can lead to adverse behavioral outcomes, and inhibiting MCs have an opposite effect. Importantly, the results appeared to be task-dependent and showed that testing both sexes was important. Additional experiments indicated what MC and GC circuitry was involved. Together, the results suggest how MCs influence behaviors that involve the DG.
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22
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Fredes F, Silva MA, Koppensteiner P, Kobayashi K, Joesch M, Shigemoto R. Ventro-dorsal Hippocampal Pathway Gates Novelty-Induced Contextual Memory Formation. Curr Biol 2021; 31:25-38.e5. [PMID: 33065009 PMCID: PMC7808756 DOI: 10.1016/j.cub.2020.09.074] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 09/08/2020] [Accepted: 09/24/2020] [Indexed: 01/07/2023]
Abstract
Novelty facilitates memory formation and is detected by both the dorsal and ventral hippocampus. Although dentate granule cells (GCs) in the dorsal hippocampus are known to mediate the formation of novelty-induced contextual memories, the required pathways and mechanisms remain unclear. Here we demonstrate that a powerful excitatory pathway from mossy cells (MCs) in the ventral hippocampus to dorsal GCs is necessary and sufficient for driving dorsal GC activation in novel environment exploration. In vivo Ca2+ imaging in freely moving mice indicated that this pathway relays environmental novelty. Furthermore, manipulation of ventral MC activity bidirectionally regulates novelty-induced contextual memory acquisition. Our results show that ventral MC activity gates contextual memory formation through an intra-hippocampal interaction activated by environmental novelty.
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Affiliation(s)
- Felipe Fredes
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria; Department of Biomedicine, Aarhus University, Ole Worms Alle 6, Building 1182, 8000 Aarhus C, Denmark.
| | - Maria Alejandra Silva
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Peter Koppensteiner
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Myodaiji, Okazaki, Japan
| | - Maximilian Joesch
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Ryuichi Shigemoto
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria.
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23
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Groisman AI, Yang SM, Schinder AF. Differential Coupling of Adult-Born Granule Cells to Parvalbumin and Somatostatin Interneurons. Cell Rep 2021; 30:202-214.e4. [PMID: 31914387 PMCID: PMC7011182 DOI: 10.1016/j.celrep.2019.12.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 10/16/2019] [Accepted: 11/27/2019] [Indexed: 12/29/2022] Open
Abstract
A strong GABAergic tone imposes sparse levels of activity in the dentate gyrus of the hippocampus. This balance is challenged by the addition of new granule cells (GCs) with high excitability. How developing GCs integrate within local inhibitory networks remains unknown. We used optogenetics to study synaptogenesis between new GCs and GABAergic interneurons expressing parvalbumin (PV-INs) and somatostatin (SST-INs). PV-INs target the soma, and synapses become mature after 6 weeks. This transition is accelerated by exposure to an enriched environment. PV-INs exert efficient control of GC spiking and participate in both feedforward and feedback loops, a mechanism that would favor lateral inhibition and sparse coding. SST-INs target the dendrites, and synapses mature after 8 weeks. Outputs from GCs onto PV-INs develop faster than those onto SST-INs. Our results reveal a long-lasting transition wherein adult-born neurons remain poorly coupled to inhibition, which might enhance activity-dependent plasticity of input and output synapses. Groisman et al. examine the integration of adult-born granule cells (GCs) to inhibitory networks of the adult hippocampus. Synapse maturation is remarkably slow for parvalbumin and somatostatin interneurons, both for connections toward and from GCs. Inhibition controls the activity of new GCs late in development.
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Affiliation(s)
- Ayelén I Groisman
- Laboratorio de Plasticidad Neuronal, Fundación Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
| | - Sung M Yang
- Laboratorio de Plasticidad Neuronal, Fundación Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
| | - Alejandro F Schinder
- Laboratorio de Plasticidad Neuronal, Fundación Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina.
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Botterill JJ, Lu YL, LaFrancois JJ, Bernstein HL, Alcantara-Gonzalez D, Jain S, Leary P, Scharfman HE. An Excitatory and Epileptogenic Effect of Dentate Gyrus Mossy Cells in a Mouse Model of Epilepsy. Cell Rep 2020; 29:2875-2889.e6. [PMID: 31775052 PMCID: PMC6905501 DOI: 10.1016/j.celrep.2019.10.100] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 09/25/2019] [Accepted: 10/24/2019] [Indexed: 12/20/2022] Open
Abstract
The sparse activity of hippocampal dentate gyrus (DG) granule cells (GCs) is thought to be critical for cognition and behavior, whereas excessive DG activity may contribute to disorders such as temporal lobe epilepsy (TLE). Glutamatergic mossy cells (MCs) of the DG are potentially critical to normal and pathological functions of the DG because they can regulate GC activity through innervation of GCs or indirectly through GABAergic neurons. Here, we test the hypothesis that MC excitation of GCs is normally weak, but under pathological conditions, MC excitation of GCs is dramatically strengthened. We show that selectively inhibiting MCs during severe seizures reduced manifestations of those seizures, hippocampal injury, and chronic epilepsy. In contrast, selectively activating MCs was pro-convulsant. Mechanistic in vitro studies using optogenetics further demonstrated the unanticipated ability of MC axons to excite GCs under pathological conditions. These results demonstrate an excitatory and epileptogenic effect of MCs in the DG.
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Affiliation(s)
- Justin J Botterill
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Yi-Ling Lu
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - John J LaFrancois
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Hannah L Bernstein
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA; Department of Neuroscience & Physiology, New York University Langone Health, New York, NY 10016, USA
| | - David Alcantara-Gonzalez
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Swati Jain
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Paige Leary
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Helen E Scharfman
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA; Department of Neuroscience & Physiology, New York University Langone Health, New York, NY 10016, USA; Department of Psychiatry, New York University Langone Health, New York, NY 10016, USA.
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Place cell maps slowly develop via competitive learning and conjunctive coding in the dentate gyrus. Nat Commun 2020; 11:4550. [PMID: 32917862 PMCID: PMC7486408 DOI: 10.1038/s41467-020-18351-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 08/19/2020] [Indexed: 01/22/2023] Open
Abstract
Place cells exhibit spatially selective firing fields that collectively map the continuum of positions in environments; how such activity pattern develops with experience is largely unknown. Here, we record putative granule cells (GCs) and mossy cells (MCs) from the dentate gyrus (DG) over 27 days as mice repetitively run through a sequence of objects fixed onto a treadmill belt. We observe a progressive transformation of GC spatial representations, from a sparse encoding of object locations and spatial patterns to increasingly more single, evenly dispersed place fields, while MCs show little transformation and preferentially encode object locations. A competitive learning model of the DG reproduces GC transformations via the progressive integration of landmark-vector cells and spatial inputs and requires MC-mediated feedforward inhibition to evenly distribute GC representations, suggesting that GCs slowly encode conjunctions of objects and spatial information via competitive learning, while MCs help homogenize GC spatial representations. Place cells in the hippocampus fire action potentials at spatially selective firing fields that collectively map the environments. Here, the authors show how these activity patterns develop with experience in mice and determine the importance of competitive learning in this process.
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Dentate Gyrus Sharp Waves, a Local Field Potential Correlate of Learning in the Dentate Gyrus of Mice. J Neurosci 2020; 40:7105-7118. [PMID: 32817247 DOI: 10.1523/jneurosci.2275-19.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 03/27/2020] [Accepted: 06/09/2020] [Indexed: 01/03/2023] Open
Abstract
The hippocampus plays an essential role in learning. Each of the three major hippocampal subfields, dentate gyrus (DG), CA3, and CA1, has a unique function in memory formation and consolidation, and also exhibit distinct local field potential (LFP) signatures during memory consolidation processes in non-rapid eye movement (NREM) sleep. The classic LFP events of the CA1 region, sharp-wave ripples (SWRs), are induced by CA3 activity and considered to be an electrophysiological biomarker for episodic memory. In LFP recordings along the dorsal CA1-DG axis from sleeping male mice, we detected and classified two types of LFP events in the DG: high-amplitude dentate spikes (DSs), and a novel event type whose current source density (CSD) signature resembled that seen during CA1 SWR, but which, most often, occurred independently of them. Because we hypothesize that this event type is similarly induced by CA3 activity, we refer to it as dentate sharp wave (DSW). We show that both DSWs and DSs differentially modulate the electrophysiological properties of SWR and multiunit activity (MUA). Following two hippocampus-dependent memory tasks, DSW occurrence rates, ripple frequencies, and ripple and sharp wave (SW) amplitudes were increased in both, while SWR occurrence rates in dorsal CA1 increased only after the spatial task. Our results suggest that DSWs, like SWRs, are induced by CA3 activity and that DSWs complement SWRs as a hippocampal LFP biomarker of memory consolidation.SIGNIFICANCE STATEMENT Awake experience is consolidated into long-term memories during sleep. Memory consolidation crucially depends on sharp-wave ripples (SWRs), which are local field potential (LFP) patterns in hippocampal CA1 that increase after learning. The dentate gyrus (DG) plays a central role in the process of memory formation, prompting us to cluster sharp waves (SWs) in the DG [dentate SWs (DSWs)] during sleep. We show that both DSW coupling to CA1 SWRs, and their occurrence rates, robustly increase after learning trials. Our results suggest that the DG is directly affected by memory consolidation processes. DSWs may thus complement SWRs as a sensitive electrophysiological biomarker of memory consolidation in mice.
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Morales C, Morici JF, Miranda M, Gallo FT, Bekinschtein P, Weisstaub NV. Neurophotonics Approaches for the Study of Pattern Separation. Front Neural Circuits 2020; 14:26. [PMID: 32587504 PMCID: PMC7298152 DOI: 10.3389/fncir.2020.00026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 04/20/2020] [Indexed: 11/26/2022] Open
Abstract
Successful memory involves not only remembering over time but also keeping memories distinct. Computational models suggest that pattern separation appears as a highly efficient process to discriminate between overlapping memories. Furthermore, lesion studies have shown that the dentate gyrus (DG) participates in pattern separation. However, these manipulations did not allow identifying the neuronal mechanism underlying pattern separation. The development of different neurophotonics techniques, together with other genetic tools, has been useful for the study of the microcircuit involved in this process. It has been shown that less-overlapped information would generate distinct neuronal representations within the granule cells (GCs). However, because glutamatergic or GABAergic cells in the DG are not functionally or structurally homogeneous, identifying the specific role of the different subpopulations remains elusive. Then, understanding pattern separation requires the ability to manipulate a temporal and spatially specific subset of cells in the DG and ideally to analyze DG cells activity in individuals performing a pattern separation dependent behavioral task. Thus, neurophotonics and calcium imaging techniques in conjunction with activity-dependent promoters and high-resolution microscopy appear as important tools for this endeavor. In this work, we review how different neurophotonics techniques have been implemented in the elucidation of a neuronal network that supports pattern separation alone or in combination with traditional techniques. We discuss the limitation of these techniques and how other neurophotonic techniques could be used to complement the advances presented up to this date.
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Affiliation(s)
- Cristian Morales
- Departamento de Psiquiatria, Centro Interdisciplinario de Neurociencia, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan Facundo Morici
- Instituto de Neurociencias Cognitiva y Traslacional (INCYT), Concejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Instituto de Neurología Cognitiva (INECO), Universidad Favaloro, Buenos Aires, Argentina
| | - Magdalena Miranda
- Instituto de Neurociencias Cognitiva y Traslacional (INCYT), Concejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Instituto de Neurología Cognitiva (INECO), Universidad Favaloro, Buenos Aires, Argentina
| | - Francisco Tomás Gallo
- Instituto de Neurociencias Cognitiva y Traslacional (INCYT), Concejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Instituto de Neurología Cognitiva (INECO), Universidad Favaloro, Buenos Aires, Argentina
| | - Pedro Bekinschtein
- Instituto de Neurociencias Cognitiva y Traslacional (INCYT), Concejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Instituto de Neurología Cognitiva (INECO), Universidad Favaloro, Buenos Aires, Argentina
| | - Noelia V. Weisstaub
- Instituto de Neurociencias Cognitiva y Traslacional (INCYT), Concejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Instituto de Neurología Cognitiva (INECO), Universidad Favaloro, Buenos Aires, Argentina
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Hsu TT, Huang TN, Hsueh YP. Anterior Commissure Regulates Neuronal Activity of Amygdalae and Influences Locomotor Activity, Social Interaction and Fear Memory in Mice. Front Mol Neurosci 2020; 13:47. [PMID: 32296306 PMCID: PMC7136557 DOI: 10.3389/fnmol.2020.00047] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 03/06/2020] [Indexed: 12/21/2022] Open
Abstract
The two hemispheres of the vertebrate brain are connected through several commissures. Although the anterior commissure (AC) is the most conserved white matter structure in the brains of different vertebrates, its complete physiological functionality remains elusive. Since the AC is involved in the connection between two amygdalae and because amygdalae are critical for emotional behaviors and social interaction, we assessed amygdalar activity and function to investigate the physiological role of the AC. We first performed ex vivo electrophysiological recording on mouse brains to demonstrate that the AC delivers a positive signal to facilitate synaptic responses and to recruit basolateral amygdalar neurons via glutamatergic synapses. Transection was then undertaken to investigate the role of the AC in vivo. Results from in vivo optogenetic stimulation suggest that AC transection impairs mutual activation between two basolateral amygdalae. Behavioral analyses were then used to assess if AC surgical lesioning results in hyperactivity, anxiety, social reduction or learning/memory impairment, which are behavioral features associated with neuropsychiatric disorders, such as autism spectrum disorders. We found that AC transection results in higher locomotor activity, aberrant social interaction and reduced associative memory, but not anxiety. Moreover, systemic administration of D-cycloserine, a coagonist of N-methyl-D-aspartate receptor, ameliorated auditory fear memory in AC-transected mice, reinforcing our evidence that the AC potentiates the activity of basolateral amygdalae. Our study suggests that the AC regulates basolateral amygdalar activity and influences neuropsychiatry-related behaviors in mice.
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Affiliation(s)
- Tsan-Ting Hsu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Tzyy-Nan Huang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yi-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
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Braganza O, Mueller-Komorowska D, Kelly T, Beck H. Quantitative properties of a feedback circuit predict frequency-dependent pattern separation. eLife 2020; 9:53148. [PMID: 32077850 PMCID: PMC7032930 DOI: 10.7554/elife.53148] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 01/20/2020] [Indexed: 12/16/2022] Open
Abstract
Feedback inhibitory motifs are thought to be important for pattern separation across species. How feedback circuits may implement pattern separation of biologically plausible, temporally structured input in mammals is, however, poorly understood. We have quantitatively determined key properties of netfeedback inhibition in the mouse dentate gyrus, a region critically involved in pattern separation. Feedback inhibition is recruited steeply with a low dynamic range (0% to 4% of active GCs), and with a non-uniform spatial profile. Additionally, net feedback inhibition shows frequency-dependent facilitation, driven by strongly facilitating mossy fiber inputs. Computational analyses show a significant contribution of the feedback circuit to pattern separation of theta modulated inputs, even within individual theta cycles. Moreover, pattern separation was selectively boosted at gamma frequencies, in particular for highly similar inputs. This effect was highly robust, suggesting that frequency-dependent pattern separation is a key feature of the feedback inhibitory microcircuit. You can probably recall where you left your car this morning without too much trouble. But assuming you use the same busy parking lot every day, can you remember which space you parked in yesterday? Or the day before that? Most people find this difficult not because they cannot remember what happened two or three days ago, but because it requires distinguishing between very similar memories. The car, the parking lot, and the time of day were the same on each occasion. So how do you remember where you parked this morning? This ability to distinguish between memories of similar events depends on a brain region called the hippocampus. A subregion of the hippocampus called the dentate gyrus generates different patterns of activity in response to events that are similar but distinct. This process is called pattern separation, and it helps ensure that you do not look for your car in yesterday’s parking space. Pattern separation in the dentate gyrus is thought to involve a form of negative feedback called feedback inhibition, a phenomenon where the output of a process acts to limit or stop the same process. To test this idea, Braganza et al. studied feedback inhibition in the dentate gyrus of mice, before building a computer model simulating the inhibition process and supplying the model with two types of realistic input. The first consisted of low-frequency theta brainwaves, which occur, for instance, in the dentate gyrus when animals explore their environment. The second consisted of higher frequency gamma brainwaves, which occur, for example, when animals experience something new. Testing the model showed that feedback inhibition contributes to pattern separation with both theta and gamma inputs. However, pattern separation is stronger with gamma input. This suggests that high frequency brainwaves in the hippocampus could help animals distinguish new events from old ones by promoting pattern separation. Various brain disorders, including Alzheimer’s disease, schizophrenia and epilepsy, involve changes in the dentate gyrus and altered brain rhythms. The current findings could help reveal how these changes contribute to memory impairments and to a reduced ability to distinguish similar experiences.
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Affiliation(s)
- Oliver Braganza
- Institute for Experimental Epileptology and Cognition Research, University of Bonn, Bonn, Germany
| | - Daniel Mueller-Komorowska
- Institute for Experimental Epileptology and Cognition Research, University of Bonn, Bonn, Germany.,International Max Planck Research School for Brain and Behavior, University of Bonn, Bonn, Germany
| | - Tony Kelly
- Institute for Experimental Epileptology and Cognition Research, University of Bonn, Bonn, Germany
| | - Heinz Beck
- Institute for Experimental Epileptology and Cognition Research, University of Bonn, Bonn, Germany.,Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Bonn, Germany
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Dentate gyrus circuits for encoding, retrieval and discrimination of episodic memories. Nat Rev Neurosci 2020; 21:153-168. [PMID: 32042144 DOI: 10.1038/s41583-019-0260-z] [Citation(s) in RCA: 203] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2019] [Indexed: 12/19/2022]
Abstract
The dentate gyrus (DG) has a key role in hippocampal memory formation. Intriguingly, DG lesions impair many, but not all, hippocampus-dependent mnemonic functions, indicating that the rest of the hippocampus (CA1-CA3) can operate autonomously under certain conditions. An extensive body of theoretical work has proposed how the architectural elements and various cell types of the DG may underlie its function in cognition. Recent studies recorded and manipulated the activity of different neuron types in the DG during memory tasks and have provided exciting new insights into the mechanisms of DG computational processes, particularly for the encoding, retrieval and discrimination of similar memories. Here, we review these DG-dependent mnemonic functions in light of the new findings and explore mechanistic links between the cellular and network properties of, and the computations performed by, the DG.
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A Toolbox of Criteria for Distinguishing Cajal-Retzius Cells from Other Neuronal Types in the Postnatal Mouse Hippocampus. eNeuro 2020; 7:ENEURO.0516-19.2019. [PMID: 31907212 PMCID: PMC7004485 DOI: 10.1523/eneuro.0516-19.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 12/12/2019] [Indexed: 01/05/2023] Open
Abstract
The study of brain circuits depends on a clear understanding of the role played by different neuronal populations. Therefore, the unambiguous identification of different cell types is essential for the correct interpretation of experimental data. Here, we emphasize to the broader neuroscience community the importance of recognizing the persistent presence of Cajal-Retzius cells in the molecular layers of the postnatal hippocampus, and then we suggest a variety of criteria for distinguishing Cajal-Retzius cells from other neurons of the hippocampal molecular layers, such as GABAergic interneurons and semilunar granule cells. The toolbox of criteria that we have investigated (in male and female mice) can be useful both for anatomical and functional experiments, and relies on the quantitative study of neuronal somatic/nuclear morphology, location and developmental profile, expression of specific molecular markers (GAD67, reelin, COUP-TFII, calretinin, and p73), single cell anatomy, and electrophysiological properties. We conclude that Cajal-Retzius cells are small, non-GABAergic neurons that are tightly associated with the hippocampal fissure (HF), and that, within this area of interest, selectively express the proteins p73 and calretinin. We highlight the dangers of using markers such as reelin or COUP-TFII to identify Cajal-Retzius cells or GABAergic interneurons because of their poor specificity. Lastly, we examine neurons of the postnatal hippocampal molecular layers and show cell type-specific differences in their dendritic/axonal morphologies and density distributions, as well as in their membrane properties and spontaneous synaptic inputs. These parameters can be used to distinguish biocytin-filled and/or electrophysiologically recorded neurons and should be considered to avoid interpretational mistakes.
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32
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Umschweif G, Greengard P, Sagi Y. The dentate gyrus in depression. Eur J Neurosci 2019; 53:39-64. [DOI: 10.1111/ejn.14640] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 11/05/2019] [Accepted: 11/28/2019] [Indexed: 12/19/2022]
Affiliation(s)
- Gali Umschweif
- Laboratory for Molecular and Cellular Neuroscience Rockefeller University New York NY USA
| | - Paul Greengard
- Laboratory for Molecular and Cellular Neuroscience Rockefeller University New York NY USA
| | - Yotam Sagi
- Laboratory for Molecular and Cellular Neuroscience Rockefeller University New York NY USA
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Tuncdemir SN, Lacefield CO, Hen R. Contributions of adult neurogenesis to dentate gyrus network activity and computations. Behav Brain Res 2019; 374:112112. [PMID: 31377252 PMCID: PMC6724741 DOI: 10.1016/j.bbr.2019.112112] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 07/18/2019] [Accepted: 07/24/2019] [Indexed: 01/01/2023]
Abstract
Anatomical observations, theoretical work and lesion experiments have led to the idea that an important function of the dentate gyrus of the mammalian hippocampus is pattern separation, a neural computation that ensures new memories are encoded without interference from previously stored memories that share similar features. The dentate gyrus also exhibits a unique form of neural plasticity that results from the continuous integration of newly born excitatory granule cells, termed adult hippocampal neurogenesis. However, the manner in which adult neurogenesis contributes to dentate gyrus network activity and computations is incompletely understood. Here, we first describe the prevailing models for the role of adult neurogenesis in dentate gyrus network function and then re-evaluate these models in the light of recent findings regarding the in vivo activity of the dentate gyrus and synaptic interactions of adult born granule cells with local circuit components, as well as, inputs, and outputs of the dentate gyrus. We propose that adult neurogenesis provides flexibility for the dentate gyrus to rapidly generate a context specific, distributed representation of important sensory stimuli such as spatial cues, which ultimately gives rise to behavioral discrimination.
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Affiliation(s)
- Sebnem Nur Tuncdemir
- Department of Psychiatry, Division of Systems Neuroscience, Columbia University and the Research Foundation for Mental Hygiene, New York State Psychiatric Institute, NY, USA.
| | - Clay Orion Lacefield
- Department of Psychiatry, Division of Systems Neuroscience, Columbia University and the Research Foundation for Mental Hygiene, New York State Psychiatric Institute, NY, USA
| | - Rene Hen
- Department of Psychiatry, Division of Systems Neuroscience, Columbia University and the Research Foundation for Mental Hygiene, New York State Psychiatric Institute, NY, USA.
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Hashimotodani Y, Karube F, Yanagawa Y, Fujiyama F, Kano M. Supramammillary Nucleus Afferents to the Dentate Gyrus Co-release Glutamate and GABA and Potentiate Granule Cell Output. Cell Rep 2019; 25:2704-2715.e4. [PMID: 30517859 DOI: 10.1016/j.celrep.2018.11.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 08/28/2018] [Accepted: 10/31/2018] [Indexed: 10/27/2022] Open
Abstract
The supramammillary nucleus (SuM) of the hypothalamus projects to the dentate gyrus (DG) and the CA2 region of the hippocampus. Although the SuM-to-hippocampus circuits have been implicated in spatial and emotional memory formation, little is known about precise neural connections between the SuM and hippocampus. Here, we report that axons of SuM neurons make monosynaptic connections to granule cells (GCs) and GABAergic interneurons, but not to hilar mossy cells, in the DG and co-release glutamate and γ-aminobutyric acid (GABA) at these synapses. Although inputs from the SuM can excite some interneurons, the inputs alone fail to generate spikes in GCs. However, despite the insufficient excitatory drive and GABAergic co-transmission, SuM inputs have net excitatory effects on GCs and can potentiate GC firing when temporally associated with perforant path inputs. Our results indicate that the SuM influences DG information processing by modulating GC outputs.
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Affiliation(s)
- Yuki Hashimotodani
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan; Laboratory of Molecular Synaptic Function, Graduate School of Brain Science, Doshisha University, Kyotanabe 610-0394, Japan.
| | - Fuyuki Karube
- Laboratory of Neural Circuitry, Graduate School of Brain Science, Doshisha University, Kyotanabe 610-0394, Japan
| | - Yuchio Yanagawa
- Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine, Maebashi 371-8511, Japan
| | - Fumino Fujiyama
- Laboratory of Neural Circuitry, Graduate School of Brain Science, Doshisha University, Kyotanabe 610-0394, Japan
| | - Masanobu Kano
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan; International Research Center for Neurointelligence (WPI-IRCN), The University of Tokyo Institutes for Advanced Study (UTIAS), The University of Tokyo, Tokyo 113-0033, Japan.
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Swaminathan A, Wichert I, Schmitz D, Maier N. Involvement of Mossy Cells in Sharp Wave-Ripple Activity In Vitro. Cell Rep 2019; 23:2541-2549. [PMID: 29847786 DOI: 10.1016/j.celrep.2018.04.095] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 01/31/2018] [Accepted: 04/23/2018] [Indexed: 12/31/2022] Open
Abstract
The role of mossy cells (MCs) of the hippocampal dentate area has long remained mysterious. Recent research has begun to unveil their significance in spatial computation of the hippocampus. Here, we used an in vitro model of sharp wave-ripple complexes (SWRs), which contribute to hippocampal memory formation, to investigate MC involvement in this fundamental population activity. We find that a significant fraction of MCs (∼47%) is recruited into the active neuronal network during SWRs in the CA3 area. Moreover, MCs receive pronounced, ripple-coherent, excitatory and inhibitory synaptic input. Finally, we find evidence for SWR-related synaptic activity in granule cells that is mediated by MCs. Given the widespread connectivity of MCs within and between hippocampi, our data suggest a role for MCs as a hub functionally coupling the CA3 and the DG during ripple-associated computations.
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Affiliation(s)
- Aarti Swaminathan
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neuroscience Research Center, 10117 Berlin, Germany; Cluster of Excellence NeuroCure, 10117 Berlin, Germany
| | - Ines Wichert
- Bernstein Center for Computational Neuroscience Berlin, 10115 Berlin, Germany
| | - Dietmar Schmitz
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neuroscience Research Center, 10117 Berlin, Germany; Bernstein Center for Computational Neuroscience Berlin, 10115 Berlin, Germany; Berlin Institute of Health, 10178 Berlin, Germany; Cluster of Excellence NeuroCure, 10117 Berlin, Germany; German Center for Neurodegenerative Diseases (DZNE) Berlin, 10117 Berlin, Germany; Einstein Center for Neurosciences Berlin, 10117 Berlin, Germany
| | - Nikolaus Maier
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neuroscience Research Center, 10117 Berlin, Germany.
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Reduced cognitive performance in aged rats correlates with increased excitation/inhibition ratio in the dentate gyrus in response to lateral entorhinal input. Neurobiol Aging 2019; 82:120-127. [DOI: 10.1016/j.neurobiolaging.2019.07.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 07/16/2019] [Accepted: 07/16/2019] [Indexed: 11/18/2022]
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Huang TN, Hsu TT, Lin MH, Chuang HC, Hu HT, Sun CP, Tao MH, Lin JY, Hsueh YP. Interhemispheric Connectivity Potentiates the Basolateral Amygdalae and Regulates Social Interaction and Memory. Cell Rep 2019; 29:34-48.e4. [PMID: 31577954 DOI: 10.1016/j.celrep.2019.08.082] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 07/30/2019] [Accepted: 08/26/2019] [Indexed: 12/21/2022] Open
Abstract
Impaired interhemispheric connectivity is commonly found in various psychiatric disorders, although how interhemispheric connectivity regulates brain function remains elusive. Here, we use the mouse amygdala, a brain region that is critical for social interaction and fear memory, as a model to demonstrate that contralateral connectivity intensifies the synaptic response of basolateral amygdalae (BLA) and regulates amygdala-dependent behaviors. Retrograde tracing and c-FOS expression indicate that contralateral afferents widely innervate BLA non-randomly and that some BLA neurons innervate both contralateral BLA and the ipsilateral central amygdala (CeA). Our optogenetic and electrophysiological studies further suggest that contralateral BLA input results in the synaptic facilitation of BLA neurons, thereby intensifying the responses to cortical and thalamic stimulations. Finally, pharmacological inhibition and chemogenetic disconnection demonstrate that BLA contralateral facilitation is required for social interaction and memory. Our study suggests that interhemispheric connectivity potentiates the synaptic dynamics of BLA neurons and is critical for the full activation and functionality of amygdalae.
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Affiliation(s)
- Tzyy-Nan Huang
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan, ROC
| | - Tsan-Ting Hsu
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan, ROC
| | - Ming-Hui Lin
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan, ROC
| | - Hsiu-Chun Chuang
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan, ROC
| | - Hsiao-Tang Hu
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan, ROC
| | - Cheng-Pu Sun
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan, ROC
| | - Mi-Hua Tao
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan, ROC
| | - John Y Lin
- School of Medicine, University of Tasmania, TAS 7000, Australia
| | - Yi-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan, ROC.
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Jung D, Kim S, Sariev A, Sharif F, Kim D, Royer S. Dentate granule and mossy cells exhibit distinct spatiotemporal responses to local change in a one-dimensional landscape of visual-tactile cues. Sci Rep 2019; 9:9545. [PMID: 31267019 PMCID: PMC6606600 DOI: 10.1038/s41598-019-45983-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 06/19/2019] [Indexed: 11/09/2022] Open
Abstract
The dentate gyrus (DG) is critical for detecting changes in environments; however, how granule cells (GCs) and mossy cells (MCs), the two excitatory cell types of the DG, respond to small changes in the object layout is unclear. Here, we recorded GCs and MCs, identified by spike feature and optogenetic tagging, as mice ran on a treadmill belt enriched with visual-tactile cues. We observed that fixing a new cue on the belt induced a reconfiguration of GC and MC spatial representations via the emergence, extinction and rate alteration of firing fields. For both GCs and MCs, the response was maximal near the cue and spread over the entire belt. However, compared to the GC response, the MC response was stronger and more immediate, peaked at a slightly earlier belt position, and exhibited a transient component reminiscent of neuromodulatory activity. A competitive neural network model reproduced the GC response contingent on both the introduction of new object-vector inputs and the reconfiguration of MC activity, the former being critical for spreading the GC response in locations distant from the cue. These findings suggest that GCs operate as a competitive network and that MCs precede GCs in detecting changes and help expand the range of GC pattern separation.
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Affiliation(s)
- Dajung Jung
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
- Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea
| | - Soyoun Kim
- Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea
| | - Anvar Sariev
- Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea
- Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology, Seoul, 02792, Republic of Korea
| | - Farnaz Sharif
- Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea
| | - Daesoo Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Sebastien Royer
- Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea.
- Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology, Seoul, 02792, Republic of Korea.
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Madar AD, Ewell LA, Jones MV. Temporal pattern separation in hippocampal neurons through multiplexed neural codes. PLoS Comput Biol 2019; 15:e1006932. [PMID: 31009459 PMCID: PMC6476466 DOI: 10.1371/journal.pcbi.1006932] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 03/06/2019] [Indexed: 12/18/2022] Open
Abstract
Pattern separation is a central concept in current theories of episodic memory: this computation is thought to support our ability to avoid confusion between similar memories by transforming similar cortical input patterns of neural activity into dissimilar output patterns before their long-term storage in the hippocampus. Because there are many ways one can define patterns of neuronal activity and the similarity between them, pattern separation could in theory be achieved through multiple coding strategies. Using our recently developed assay that evaluates pattern separation in isolated tissue by controlling and recording the input and output spike trains of single hippocampal neurons, we explored neural codes through which pattern separation is performed by systematic testing of different similarity metrics and various time resolutions. We discovered that granule cells, the projection neurons of the dentate gyrus, can exhibit both pattern separation and its opposite computation, pattern convergence, depending on the neural code considered and the statistical structure of the input patterns. Pattern separation is favored when inputs are highly similar, and is achieved through spike time reorganization at short time scales (< 100 ms) as well as through variations in firing rate and burstiness at longer time scales. These multiplexed forms of pattern separation are network phenomena, notably controlled by GABAergic inhibition, that involve many celltypes with input-output transformations that participate in pattern separation to different extents and with complementary neural codes: a rate code for dentate fast-spiking interneurons, a burstiness code for hilar mossy cells and a synchrony code at long time scales for CA3 pyramidal cells. Therefore, the isolated hippocampal circuit itself is capable of performing temporal pattern separation using multiplexed coding strategies that might be essential to optimally disambiguate multimodal mnemonic representations.
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Affiliation(s)
- Antoine D. Madar
- Department of Neuroscience, University of Wisconsin-Madison, WI, United States of America
- Neuroscience Training Program, University of Wisconsin-Madison, WI, United States of America
- Department of Neurobiology, Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior, University of Chicago, IL, United States of America
| | - Laura A. Ewell
- Department of Neuroscience, University of Wisconsin-Madison, WI, United States of America
- Institute of Experimental Epileptology and Cognition Research, University of Bonn–Medical Center, Germany
| | - Mathew V. Jones
- Department of Neuroscience, University of Wisconsin-Madison, WI, United States of America
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Scharfman HE. Advances in understanding hilar mossy cells of the dentate gyrus. Cell Tissue Res 2018; 373:643-652. [PMID: 29222692 PMCID: PMC5993616 DOI: 10.1007/s00441-017-2750-5] [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] [Received: 08/21/2017] [Accepted: 11/21/2017] [Indexed: 02/01/2023]
Abstract
Hilar mossy cells (MCs) of the dentate gyrus (DG) distinguish the DG from other hippocampal subfields (CA1-3) because there are two glutamatergic cell types in the DG rather than one. Thus, in the DG, the main cell types include glutamatergic granule cells (GCs) and MCs, whereas in CA1-3, the only glutamatergic cell type is the pyramidal cell. In contrast to GCs, MCs are different in morphology, intrinsic electrophysiological properties, afferent input and axonal projections, so their function is likely to be very different from GCs. Why are MCs necessary to the DG? In past studies, the answer has been unclear because MCs not only excite GCs directly but also inhibit them disynaptically, by exciting GABAergic neurons that project to GCs. Results of new studies are discussed that shed light on this issue. These studies take advantage of recently available transgenic mice with Cre recombinase expression mostly in MCs and techniques such as optogenetics and DREADDs (designer receptors exclusively activated by designer drugs). The recent studies also address in vivo behavioral functions of MCs. Some of the results support past hypotheses whereas others suggest new conceptualizations of how the MCs contribute to DG circuitry and function. While substantial progess has been made, additional research is still needed to clarify the characteristics and functions of these unique cells.
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Affiliation(s)
- Helen E Scharfman
- Departments of Child & Adolescent Psychiatry, Neuroscience & Physiology, Psychiatry, and the New York University Neuroscience Institute, New York University Langone Medical Center, One Park Avenue, 7th floor, New York, NY, 10016, USA.
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Building 39, Orangeburg, NY, 10962, USA.
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Anstötz M, Quattrocolo G, Maccaferri G. Cajal-Retzius cells and GABAergic interneurons of the developing hippocampus: Close electrophysiological encounters of the third kind. Brain Res 2018; 1697:124-133. [PMID: 30071194 DOI: 10.1016/j.brainres.2018.07.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 07/17/2018] [Accepted: 07/28/2018] [Indexed: 01/24/2023]
Abstract
In contrast to the large number of studies investigating the electrophysiological properties and synaptic connectivity of hippocampal pyramidal neurons, granule cells, and GABAergic interneurons, much less is known about Cajal-Retzius cells. In this review article, we discuss the possible reasons underlying this difference, and review experimental work performed on this cell type in the hippocampus, comparing it with results obtained in the neocortex. Our main emphasis is on data obtained with in vitro electrophysiology. In particular, we address the bidirectional connectivity between Cajal-Retzius cells and GABAergic interneurons, examine their synaptic properties and propose specific functions of Cajal-Retzius cell/GABAergic interneuron microcircuits. Lastly, we discuss the potential involvement of these microcircuits in critical physiological hippocampal functions such as postnatal neurogenesis or pathological scenarios such as temporal lobe epilepsy.
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Affiliation(s)
- Max Anstötz
- Department of Physiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Giulia Quattrocolo
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, Trondheim, Norway
| | - Gianmaria Maccaferri
- Department of Physiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA.
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42
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Mossy Cells Control Adult Neural Stem Cell Quiescence and Maintenance through a Dynamic Balance between Direct and Indirect Pathways. Neuron 2018; 99:493-510.e4. [PMID: 30057205 DOI: 10.1016/j.neuron.2018.07.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 05/16/2018] [Accepted: 07/05/2018] [Indexed: 11/23/2022]
Abstract
Mossy cells (MCs) represent a major population of excitatory neurons in the adult dentate gyrus, a brain region where new neurons are generated from radial neural stem cells (rNSCs) throughout life. Little is known about the role of MCs in regulating rNSCs. Here we demonstrate that MC commissural projections structurally and functionally interact with rNSCs through both the direct glutamatergic MC-rNSC pathway and the indirect GABAergic MC-local interneuron-rNSC pathway. Specifically, moderate MC activation increases rNSC quiescence through the dominant indirect pathway, while high MC activation increases rNSC activation through the dominant direct pathway. In contrast, MC inhibition or ablation leads to a transient increase of rNSC activation, but rNSC depletion only occurs after chronic ablation of MCs. Together, our study identifies MCs as a critical stem cell niche component that dynamically controls adult NSC quiescence and maintenance under various MC activity states through a balance of direct glutamatergic and indirect GABAergic signaling onto rNSCs.
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43
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Bui AD, Nguyen TM, Limouse C, Kim HK, Szabo GG, Felong S, Maroso M, Soltesz I. Dentate gyrus mossy cells control spontaneous convulsive seizures and spatial memory. Science 2018; 359:787-790. [PMID: 29449490 DOI: 10.1126/science.aan4074] [Citation(s) in RCA: 159] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 12/21/2017] [Indexed: 01/06/2023]
Abstract
Temporal lobe epilepsy (TLE) is characterized by debilitating, recurring seizures and an increased risk for cognitive deficits. Mossy cells (MCs) are key neurons in the hippocampal excitatory circuit, and the partial loss of MCs is a major hallmark of TLE. We investigated how MCs contribute to spontaneous ictal activity and to spatial contextual memory in a mouse model of TLE with hippocampal sclerosis, using a combination of optogenetic, electrophysiological, and behavioral approaches. In chronically epileptic mice, real-time optogenetic modulation of MCs during spontaneous hippocampal seizures controlled the progression of activity from an electrographic to convulsive seizure. Decreased MC activity is sufficient to impede encoding of spatial context, recapitulating observed cognitive deficits in chronically epileptic mice.
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Affiliation(s)
- Anh D Bui
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA. .,Department of Anatomy and Neurobiology, University of California, Irvine, CA 92697, USA
| | - Theresa M Nguyen
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA
| | - Charles Limouse
- Department of Applied Physics, Stanford University, Stanford, CA 94305, USA
| | - Hannah K Kim
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA
| | - Gergely G Szabo
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA
| | - Sylwia Felong
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA
| | - Mattia Maroso
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA
| | - Ivan Soltesz
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA
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44
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Automated measurement of hippocampal subfields in PTSD: Evidence for smaller dentate gyrus volume. J Psychiatr Res 2017; 95:247-252. [PMID: 28923718 PMCID: PMC6816338 DOI: 10.1016/j.jpsychires.2017.09.007] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 08/25/2017] [Accepted: 09/07/2017] [Indexed: 12/16/2022]
Abstract
Smaller hippocampal volume has been consistently observed as a biomarker of posttraumatic stress disorder (PTSD). However, less is known about individual volumes of the subfields composing the hippocampus such as the dentate gyrus and cornu ammonis (CA) fields 1-4 in PTSD. The aim of the present study was to examine the hypothesis that volume of the dentate gyrus, a region putatively involved in distinctive encoding of similar events, is smaller in individuals with PTSD versus trauma-exposed controls. Ninety-seven recent war veterans underwent structural imaging on a 3T scanner and were assessed for PTSD using the Clinician-Administered PTSD Scale. The hippocampal subfield automated segmentation program available through FreeSurfer was used to segment the CA4/dentate gyrus, CA1, CA2/3, presubiculum, and subiculum of the hippocampus. Results showed that CA4/dentate gyrus subfield volume was significantly smaller in veterans with PTSD and scaled inversely with PTSD symptom severity. These results support the view that dentate gyrus abnormalities are associated with symptoms of PTSD, although additional evidence is necessary to determine whether these abnormalities underlie fear generalization and other memory alterations in PTSD.
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45
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Abstract
The impact of dentate mossy cells on hippocampal activity remained uncertain despite a long history of investigation. In this issue of Neuron, Hashimotodani et al. (2017) discover a presynaptically expressed form of long-term potentiation at mossy cell outputs, shedding light on their mysterious function.
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Affiliation(s)
- Aaron D Milstein
- Department of Neurosurgery & Stanford Neurosciences Institute, Stanford University School of Medicine, Stanford, CA 94304, USA
| | - Ivan Soltesz
- Department of Neurosurgery & Stanford Neurosciences Institute, Stanford University School of Medicine, Stanford, CA 94304, USA.
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46
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Hashimotodani Y, Nasrallah K, Jensen KR, Chávez AE, Carrera D, Castillo PE. LTP at Hilar Mossy Cell-Dentate Granule Cell Synapses Modulates Dentate Gyrus Output by Increasing Excitation/Inhibition Balance. Neuron 2017; 95:928-943.e3. [PMID: 28817805 PMCID: PMC5609819 DOI: 10.1016/j.neuron.2017.07.028] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 06/23/2017] [Accepted: 07/25/2017] [Indexed: 01/20/2023]
Abstract
Excitatory hilar mossy cells (MCs) in the dentate gyrus receive inputs from dentate granule cells (GCs) and project back to GCs locally, contralaterally, and along the longitudinal axis of the hippocampus, thereby establishing an associative positive-feedback loop and connecting functionally diverse hippocampal areas. MCs also synapse with GABAergic interneurons that mediate feed-forward inhibition onto GCs. Surprisingly, although these circuits have been implicated in both memory formation (e.g., pattern separation) and temporal lobe epilepsy, little is known about activity-dependent plasticity of their synaptic connections. Here, we report that MC-GC synapses undergo a presynaptic, NMDA-receptor-independent form of long-term potentiation (LTP) that requires postsynaptic brain-derived neurotrophic factor (BDNF)/TrkB and presynaptic cyclic AMP (cAMP)/PKA signaling. This LTP is input specific and selectively expressed at MC-GC synapses, but not at the disynaptic inhibitory loop. By increasing the excitation/inhibition balance, MC-GC LTP enhances GC output at the associative MC-GC recurrent circuit and may contribute to dentate-dependent forms of learning and epilepsy.
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Affiliation(s)
- Yuki Hashimotodani
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Kaoutsar Nasrallah
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Kyle R Jensen
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Andrés E Chávez
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Daniel Carrera
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Pablo E Castillo
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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47
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Moretto JN, Duffy ÁM, Scharfman HE. Acute restraint stress decreases c-fos immunoreactivity in hilar mossy cells of the adult dentate gyrus. Brain Struct Funct 2017; 222:2405-2419. [PMID: 28190104 DOI: 10.1007/s00429-016-1349-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 12/14/2016] [Indexed: 11/29/2022]
Abstract
Although a great deal of information is available about the circuitry of the mossy cells (MCs) of the dentate gyrus (DG) hilus, their activity in vivo is not clear. The immediate early gene c-fos can be used to gain insight into the activity of MCs in vivo, because c-fos protein expression reflects increased neuronal activity. In prior work, it was identified that control rats that were perfusion-fixed after removal from their home cage exhibited c-fos immunoreactivity (ir) in the DG in a spatially stereotyped pattern: ventral MCs and dorsal granule cells (GCs) expressed c-fos protein (Duffy et al., Hippocampus 23:649-655, 2013). In this study, we hypothesized that restraint stress would alter c-fos-ir, because MCs express glucocorticoid type 2 receptors and the DG is considered to be involved in behaviors related to stress or anxiety. We show that acute restraint using a transparent nose cone for just 10 min led to reduced c-fos-ir in ventral MCs compared to control rats. In these comparisons, c-fos-ir was evaluated 30 min after the 10 min-long period of restraint, and if evaluation was later than 30 min c-fos-ir was no longer suppressed. Granule cells (GCs) also showed suppressed c-fos-ir after acute restraint, but it was different than MCs, because the suppression persisted for over 30 min after the restraint. We conclude that c-fos protein expression is rapidly and transiently reduced in ventral hilar MCs after a brief period of restraint, and suppressed longer in dorsal GCs.
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Affiliation(s)
- Jillian N Moretto
- The Nathan Kline Institute of Psychiatric Research, Orangeburg, NY, 10962, USA
| | - Áine M Duffy
- The Nathan Kline Institute of Psychiatric Research, Orangeburg, NY, 10962, USA
| | - Helen E Scharfman
- The Nathan Kline Institute of Psychiatric Research, Orangeburg, NY, 10962, USA. .,Departments of Child and Adolescent Psychiatry, Physiology and Neuroscience, and Psychiatry, New York University Langone Medical Center, New York, NY, 10016, USA.
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48
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Exposure to prolonged controllable or uncontrollable stress affects GABAergic function in sub-regions of the hippocampus and the amygdala. Neurobiol Learn Mem 2017; 138:271-280. [DOI: 10.1016/j.nlm.2016.06.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 06/05/2016] [Accepted: 06/13/2016] [Indexed: 11/20/2022]
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49
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Kelly T, Beck H. Functional properties of granule cells with hilar basal dendrites in the epileptic dentate gyrus. Epilepsia 2016; 58:160-171. [PMID: 27888509 DOI: 10.1111/epi.13605] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/10/2016] [Indexed: 01/24/2023]
Abstract
OBJECTIVE The maturation of adult-born granule cells and their functional integration into the network is thought to play a key role in the proper functioning of the dentate gyrus. In temporal lobe epilepsy, adult-born granule cells in the dentate gyrus develop abnormally and possess a hilar basal dendrite (HBD). Although morphological studies have shown that these HBDs have synapses, little is known about the functional properties of these HBDs or the intrinsic and network properties of the granule cells that possess these aberrant dendrites. METHODS We performed patch-clamp recordings of granule cells within the granule cell layer "normotopic" from sham-control and status epilepticus (SE) animals. Normotopic granule cells from SE animals possessed an HBD (SE+ HBD+ cells) or not (SE+ HBD- cells). Apical and basal dendrites were stimulated using multiphoton uncaging of glutamate. Two-photon Ca2+ imaging was used to measure Ca2+ transients associated with back-propagating action potentials (bAPs). RESULTS Near-synchronous synaptic input integrated linearly in apical dendrites from sham-control animals and was not significantly different in apical dendrites of SE+ HBD- cells. The majority of HBDs integrated input linearly, similar to apical dendrites. However, 2 of 11 HBDs were capable of supralinear integration mediated by a dendritic spike. Furthermore, the bAP-evoked Ca2+ transients were relatively well maintained along HBDs, compared with apical dendrites. This further suggests an enhanced electrogenesis in HBDs. In addition, the output of granule cells from epileptic tissue was enhanced, with both SE+ HBD- and SE+ HBD+ cells displaying increased high-frequency (>100 Hz) burst-firing. Finally, both SE+ HBD- and SE+ HBD+ cells received recurrent excitatory input that was capable of generating APs, especially in the absence of feedback inhibition. SIGNIFICANCE Taken together, these data suggest that the enhanced excitability of HBDs combined with the altered intrinsic and network properties of granule cells collude to promote excitability and synchrony in the epileptic dentate gyrus.
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Affiliation(s)
- Tony Kelly
- Laboratory for Experimental Epileptology and Cognition Research, Department of Epileptology, University of Bonn, Bonn, Germany
| | - Heinz Beck
- Laboratory for Experimental Epileptology and Cognition Research, Department of Epileptology, University of Bonn, Bonn, Germany.,German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
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50
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Lee CT, Kao MH, Hou WH, Wei YT, Chen CL, Lien CC. Causal Evidence for the Role of Specific GABAergic Interneuron Types in Entorhinal Recruitment of Dentate Granule Cells. Sci Rep 2016; 6:36885. [PMID: 27830729 PMCID: PMC5103275 DOI: 10.1038/srep36885] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 10/24/2016] [Indexed: 01/16/2023] Open
Abstract
The dentate gyrus (DG) is the primary gate of the hippocampus and controls information flow from the cortex to the hippocampus proper. To maintain normal function, granule cells (GCs), the principal neurons in the DG, receive fine-tuned inhibition from local-circuit GABAergic inhibitory interneurons (INs). Abnormalities of GABAergic circuits in the DG are associated with several brain disorders, including epilepsy, autism, schizophrenia, and Alzheimer disease. Therefore, understanding the network mechanisms of inhibitory control of GCs is of functional and pathophysiological importance. GABAergic inhibitory INs are heterogeneous, but it is unclear how individual subtypes contribute to GC activity. Using cell-type-specific optogenetic perturbation, we investigated whether and how two major IN populations defined by parvalbumin (PV) and somatostatin (SST) expression, regulate GC input transformations. We showed that PV-expressing (PV+) INs, and not SST-expressing (SST+) INs, primarily suppress GC responses to single cortical stimulation. In addition, these two IN classes differentially regulate GC responses to θ and γ frequency inputs from the cortex. Notably, PV+ INs specifically control the onset of the spike series, whereas SST+ INs preferentially regulate the later spikes in the series. Together, PV+ and SST+ GABAergic INs engage differentially in GC input-output transformations in response to various activity patterns.
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Affiliation(s)
- Cheng-Ta Lee
- Institute of Neuroscience, National Yang-Ming University, 155, Section 2, Li-Nong Street, Taipei 112, Taiwan
| | - Min-Hua Kao
- Institute of Neuroscience, National Yang-Ming University, 155, Section 2, Li-Nong Street, Taipei 112, Taiwan
| | - Wen-Hsien Hou
- Institute of Neuroscience, National Yang-Ming University, 155, Section 2, Li-Nong Street, Taipei 112, Taiwan
| | - Yu-Ting Wei
- Institute of Neuroscience, National Yang-Ming University, 155, Section 2, Li-Nong Street, Taipei 112, Taiwan
| | - Chin-Lin Chen
- Institute of Neuroscience, National Yang-Ming University, 155, Section 2, Li-Nong Street, Taipei 112, Taiwan
| | - Cheng-Chang Lien
- Institute of Neuroscience, National Yang-Ming University, 155, Section 2, Li-Nong Street, Taipei 112, Taiwan
- Institute of Brain Science, National Yang-Ming University, 155, Section 2, Li-Nong Street, Taipei 112, Taiwan
- Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan
- Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
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